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TOMOYO Linux Cross Reference
Linux/net/core/filter.c

Version: ~ [ linux-4.15-rc3 ] ~ [ linux-4.14.5 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.68 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.105 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.47 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.87 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.51 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.96 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.39.4 ] ~ [ linux-2.6.38.8 ] ~ [ linux-2.6.37.6 ] ~ [ linux-2.6.36.4 ] ~ [ linux-2.6.35.14 ] ~ [ linux-2.6.34.15 ] ~ [ linux-2.6.33.20 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.27.62 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
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  1 /*
  2  * Linux Socket Filter - Kernel level socket filtering
  3  *
  4  * Based on the design of the Berkeley Packet Filter. The new
  5  * internal format has been designed by PLUMgrid:
  6  *
  7  *      Copyright (c) 2011 - 2014 PLUMgrid, http://plumgrid.com
  8  *
  9  * Authors:
 10  *
 11  *      Jay Schulist <jschlst@samba.org>
 12  *      Alexei Starovoitov <ast@plumgrid.com>
 13  *      Daniel Borkmann <dborkman@redhat.com>
 14  *
 15  * This program is free software; you can redistribute it and/or
 16  * modify it under the terms of the GNU General Public License
 17  * as published by the Free Software Foundation; either version
 18  * 2 of the License, or (at your option) any later version.
 19  *
 20  * Andi Kleen - Fix a few bad bugs and races.
 21  * Kris Katterjohn - Added many additional checks in bpf_check_classic()
 22  */
 23 
 24 #include <linux/module.h>
 25 #include <linux/types.h>
 26 #include <linux/mm.h>
 27 #include <linux/fcntl.h>
 28 #include <linux/socket.h>
 29 #include <linux/sock_diag.h>
 30 #include <linux/in.h>
 31 #include <linux/inet.h>
 32 #include <linux/netdevice.h>
 33 #include <linux/if_packet.h>
 34 #include <linux/if_arp.h>
 35 #include <linux/gfp.h>
 36 #include <net/ip.h>
 37 #include <net/protocol.h>
 38 #include <net/netlink.h>
 39 #include <linux/skbuff.h>
 40 #include <net/sock.h>
 41 #include <net/flow_dissector.h>
 42 #include <linux/errno.h>
 43 #include <linux/timer.h>
 44 #include <linux/uaccess.h>
 45 #include <asm/unaligned.h>
 46 #include <asm/cmpxchg.h>
 47 #include <linux/filter.h>
 48 #include <linux/ratelimit.h>
 49 #include <linux/seccomp.h>
 50 #include <linux/if_vlan.h>
 51 #include <linux/bpf.h>
 52 #include <net/sch_generic.h>
 53 #include <net/cls_cgroup.h>
 54 #include <net/dst_metadata.h>
 55 #include <net/dst.h>
 56 #include <net/sock_reuseport.h>
 57 #include <net/busy_poll.h>
 58 #include <net/tcp.h>
 59 #include <linux/bpf_trace.h>
 60 
 61 /**
 62  *      sk_filter_trim_cap - run a packet through a socket filter
 63  *      @sk: sock associated with &sk_buff
 64  *      @skb: buffer to filter
 65  *      @cap: limit on how short the eBPF program may trim the packet
 66  *
 67  * Run the eBPF program and then cut skb->data to correct size returned by
 68  * the program. If pkt_len is 0 we toss packet. If skb->len is smaller
 69  * than pkt_len we keep whole skb->data. This is the socket level
 70  * wrapper to BPF_PROG_RUN. It returns 0 if the packet should
 71  * be accepted or -EPERM if the packet should be tossed.
 72  *
 73  */
 74 int sk_filter_trim_cap(struct sock *sk, struct sk_buff *skb, unsigned int cap)
 75 {
 76         int err;
 77         struct sk_filter *filter;
 78 
 79         /*
 80          * If the skb was allocated from pfmemalloc reserves, only
 81          * allow SOCK_MEMALLOC sockets to use it as this socket is
 82          * helping free memory
 83          */
 84         if (skb_pfmemalloc(skb) && !sock_flag(sk, SOCK_MEMALLOC)) {
 85                 NET_INC_STATS(sock_net(sk), LINUX_MIB_PFMEMALLOCDROP);
 86                 return -ENOMEM;
 87         }
 88         err = BPF_CGROUP_RUN_PROG_INET_INGRESS(sk, skb);
 89         if (err)
 90                 return err;
 91 
 92         err = security_sock_rcv_skb(sk, skb);
 93         if (err)
 94                 return err;
 95 
 96         rcu_read_lock();
 97         filter = rcu_dereference(sk->sk_filter);
 98         if (filter) {
 99                 struct sock *save_sk = skb->sk;
100                 unsigned int pkt_len;
101 
102                 skb->sk = sk;
103                 pkt_len = bpf_prog_run_save_cb(filter->prog, skb);
104                 skb->sk = save_sk;
105                 err = pkt_len ? pskb_trim(skb, max(cap, pkt_len)) : -EPERM;
106         }
107         rcu_read_unlock();
108 
109         return err;
110 }
111 EXPORT_SYMBOL(sk_filter_trim_cap);
112 
113 BPF_CALL_1(__skb_get_pay_offset, struct sk_buff *, skb)
114 {
115         return skb_get_poff(skb);
116 }
117 
118 BPF_CALL_3(__skb_get_nlattr, struct sk_buff *, skb, u32, a, u32, x)
119 {
120         struct nlattr *nla;
121 
122         if (skb_is_nonlinear(skb))
123                 return 0;
124 
125         if (skb->len < sizeof(struct nlattr))
126                 return 0;
127 
128         if (a > skb->len - sizeof(struct nlattr))
129                 return 0;
130 
131         nla = nla_find((struct nlattr *) &skb->data[a], skb->len - a, x);
132         if (nla)
133                 return (void *) nla - (void *) skb->data;
134 
135         return 0;
136 }
137 
138 BPF_CALL_3(__skb_get_nlattr_nest, struct sk_buff *, skb, u32, a, u32, x)
139 {
140         struct nlattr *nla;
141 
142         if (skb_is_nonlinear(skb))
143                 return 0;
144 
145         if (skb->len < sizeof(struct nlattr))
146                 return 0;
147 
148         if (a > skb->len - sizeof(struct nlattr))
149                 return 0;
150 
151         nla = (struct nlattr *) &skb->data[a];
152         if (nla->nla_len > skb->len - a)
153                 return 0;
154 
155         nla = nla_find_nested(nla, x);
156         if (nla)
157                 return (void *) nla - (void *) skb->data;
158 
159         return 0;
160 }
161 
162 BPF_CALL_0(__get_raw_cpu_id)
163 {
164         return raw_smp_processor_id();
165 }
166 
167 static const struct bpf_func_proto bpf_get_raw_smp_processor_id_proto = {
168         .func           = __get_raw_cpu_id,
169         .gpl_only       = false,
170         .ret_type       = RET_INTEGER,
171 };
172 
173 static u32 convert_skb_access(int skb_field, int dst_reg, int src_reg,
174                               struct bpf_insn *insn_buf)
175 {
176         struct bpf_insn *insn = insn_buf;
177 
178         switch (skb_field) {
179         case SKF_AD_MARK:
180                 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, mark) != 4);
181 
182                 *insn++ = BPF_LDX_MEM(BPF_W, dst_reg, src_reg,
183                                       offsetof(struct sk_buff, mark));
184                 break;
185 
186         case SKF_AD_PKTTYPE:
187                 *insn++ = BPF_LDX_MEM(BPF_B, dst_reg, src_reg, PKT_TYPE_OFFSET());
188                 *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, PKT_TYPE_MAX);
189 #ifdef __BIG_ENDIAN_BITFIELD
190                 *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 5);
191 #endif
192                 break;
193 
194         case SKF_AD_QUEUE:
195                 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, queue_mapping) != 2);
196 
197                 *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
198                                       offsetof(struct sk_buff, queue_mapping));
199                 break;
200 
201         case SKF_AD_VLAN_TAG:
202         case SKF_AD_VLAN_TAG_PRESENT:
203                 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_tci) != 2);
204                 BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000);
205 
206                 /* dst_reg = *(u16 *) (src_reg + offsetof(vlan_tci)) */
207                 *insn++ = BPF_LDX_MEM(BPF_H, dst_reg, src_reg,
208                                       offsetof(struct sk_buff, vlan_tci));
209                 if (skb_field == SKF_AD_VLAN_TAG) {
210                         *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg,
211                                                 ~VLAN_TAG_PRESENT);
212                 } else {
213                         /* dst_reg >>= 12 */
214                         *insn++ = BPF_ALU32_IMM(BPF_RSH, dst_reg, 12);
215                         /* dst_reg &= 1 */
216                         *insn++ = BPF_ALU32_IMM(BPF_AND, dst_reg, 1);
217                 }
218                 break;
219         }
220 
221         return insn - insn_buf;
222 }
223 
224 static bool convert_bpf_extensions(struct sock_filter *fp,
225                                    struct bpf_insn **insnp)
226 {
227         struct bpf_insn *insn = *insnp;
228         u32 cnt;
229 
230         switch (fp->k) {
231         case SKF_AD_OFF + SKF_AD_PROTOCOL:
232                 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, protocol) != 2);
233 
234                 /* A = *(u16 *) (CTX + offsetof(protocol)) */
235                 *insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
236                                       offsetof(struct sk_buff, protocol));
237                 /* A = ntohs(A) [emitting a nop or swap16] */
238                 *insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
239                 break;
240 
241         case SKF_AD_OFF + SKF_AD_PKTTYPE:
242                 cnt = convert_skb_access(SKF_AD_PKTTYPE, BPF_REG_A, BPF_REG_CTX, insn);
243                 insn += cnt - 1;
244                 break;
245 
246         case SKF_AD_OFF + SKF_AD_IFINDEX:
247         case SKF_AD_OFF + SKF_AD_HATYPE:
248                 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, ifindex) != 4);
249                 BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, type) != 2);
250 
251                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
252                                       BPF_REG_TMP, BPF_REG_CTX,
253                                       offsetof(struct sk_buff, dev));
254                 /* if (tmp != 0) goto pc + 1 */
255                 *insn++ = BPF_JMP_IMM(BPF_JNE, BPF_REG_TMP, 0, 1);
256                 *insn++ = BPF_EXIT_INSN();
257                 if (fp->k == SKF_AD_OFF + SKF_AD_IFINDEX)
258                         *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_TMP,
259                                             offsetof(struct net_device, ifindex));
260                 else
261                         *insn = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_TMP,
262                                             offsetof(struct net_device, type));
263                 break;
264 
265         case SKF_AD_OFF + SKF_AD_MARK:
266                 cnt = convert_skb_access(SKF_AD_MARK, BPF_REG_A, BPF_REG_CTX, insn);
267                 insn += cnt - 1;
268                 break;
269 
270         case SKF_AD_OFF + SKF_AD_RXHASH:
271                 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, hash) != 4);
272 
273                 *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX,
274                                     offsetof(struct sk_buff, hash));
275                 break;
276 
277         case SKF_AD_OFF + SKF_AD_QUEUE:
278                 cnt = convert_skb_access(SKF_AD_QUEUE, BPF_REG_A, BPF_REG_CTX, insn);
279                 insn += cnt - 1;
280                 break;
281 
282         case SKF_AD_OFF + SKF_AD_VLAN_TAG:
283                 cnt = convert_skb_access(SKF_AD_VLAN_TAG,
284                                          BPF_REG_A, BPF_REG_CTX, insn);
285                 insn += cnt - 1;
286                 break;
287 
288         case SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT:
289                 cnt = convert_skb_access(SKF_AD_VLAN_TAG_PRESENT,
290                                          BPF_REG_A, BPF_REG_CTX, insn);
291                 insn += cnt - 1;
292                 break;
293 
294         case SKF_AD_OFF + SKF_AD_VLAN_TPID:
295                 BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_proto) != 2);
296 
297                 /* A = *(u16 *) (CTX + offsetof(vlan_proto)) */
298                 *insn++ = BPF_LDX_MEM(BPF_H, BPF_REG_A, BPF_REG_CTX,
299                                       offsetof(struct sk_buff, vlan_proto));
300                 /* A = ntohs(A) [emitting a nop or swap16] */
301                 *insn = BPF_ENDIAN(BPF_FROM_BE, BPF_REG_A, 16);
302                 break;
303 
304         case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
305         case SKF_AD_OFF + SKF_AD_NLATTR:
306         case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
307         case SKF_AD_OFF + SKF_AD_CPU:
308         case SKF_AD_OFF + SKF_AD_RANDOM:
309                 /* arg1 = CTX */
310                 *insn++ = BPF_MOV64_REG(BPF_REG_ARG1, BPF_REG_CTX);
311                 /* arg2 = A */
312                 *insn++ = BPF_MOV64_REG(BPF_REG_ARG2, BPF_REG_A);
313                 /* arg3 = X */
314                 *insn++ = BPF_MOV64_REG(BPF_REG_ARG3, BPF_REG_X);
315                 /* Emit call(arg1=CTX, arg2=A, arg3=X) */
316                 switch (fp->k) {
317                 case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
318                         *insn = BPF_EMIT_CALL(__skb_get_pay_offset);
319                         break;
320                 case SKF_AD_OFF + SKF_AD_NLATTR:
321                         *insn = BPF_EMIT_CALL(__skb_get_nlattr);
322                         break;
323                 case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
324                         *insn = BPF_EMIT_CALL(__skb_get_nlattr_nest);
325                         break;
326                 case SKF_AD_OFF + SKF_AD_CPU:
327                         *insn = BPF_EMIT_CALL(__get_raw_cpu_id);
328                         break;
329                 case SKF_AD_OFF + SKF_AD_RANDOM:
330                         *insn = BPF_EMIT_CALL(bpf_user_rnd_u32);
331                         bpf_user_rnd_init_once();
332                         break;
333                 }
334                 break;
335 
336         case SKF_AD_OFF + SKF_AD_ALU_XOR_X:
337                 /* A ^= X */
338                 *insn = BPF_ALU32_REG(BPF_XOR, BPF_REG_A, BPF_REG_X);
339                 break;
340 
341         default:
342                 /* This is just a dummy call to avoid letting the compiler
343                  * evict __bpf_call_base() as an optimization. Placed here
344                  * where no-one bothers.
345                  */
346                 BUG_ON(__bpf_call_base(0, 0, 0, 0, 0) != 0);
347                 return false;
348         }
349 
350         *insnp = insn;
351         return true;
352 }
353 
354 /**
355  *      bpf_convert_filter - convert filter program
356  *      @prog: the user passed filter program
357  *      @len: the length of the user passed filter program
358  *      @new_prog: allocated 'struct bpf_prog' or NULL
359  *      @new_len: pointer to store length of converted program
360  *
361  * Remap 'sock_filter' style classic BPF (cBPF) instruction set to 'bpf_insn'
362  * style extended BPF (eBPF).
363  * Conversion workflow:
364  *
365  * 1) First pass for calculating the new program length:
366  *   bpf_convert_filter(old_prog, old_len, NULL, &new_len)
367  *
368  * 2) 2nd pass to remap in two passes: 1st pass finds new
369  *    jump offsets, 2nd pass remapping:
370  *   bpf_convert_filter(old_prog, old_len, new_prog, &new_len);
371  */
372 static int bpf_convert_filter(struct sock_filter *prog, int len,
373                               struct bpf_prog *new_prog, int *new_len)
374 {
375         int new_flen = 0, pass = 0, target, i, stack_off;
376         struct bpf_insn *new_insn, *first_insn = NULL;
377         struct sock_filter *fp;
378         int *addrs = NULL;
379         u8 bpf_src;
380 
381         BUILD_BUG_ON(BPF_MEMWORDS * sizeof(u32) > MAX_BPF_STACK);
382         BUILD_BUG_ON(BPF_REG_FP + 1 != MAX_BPF_REG);
383 
384         if (len <= 0 || len > BPF_MAXINSNS)
385                 return -EINVAL;
386 
387         if (new_prog) {
388                 first_insn = new_prog->insnsi;
389                 addrs = kcalloc(len, sizeof(*addrs),
390                                 GFP_KERNEL | __GFP_NOWARN);
391                 if (!addrs)
392                         return -ENOMEM;
393         }
394 
395 do_pass:
396         new_insn = first_insn;
397         fp = prog;
398 
399         /* Classic BPF related prologue emission. */
400         if (new_prog) {
401                 /* Classic BPF expects A and X to be reset first. These need
402                  * to be guaranteed to be the first two instructions.
403                  */
404                 *new_insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_A, BPF_REG_A);
405                 *new_insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_X, BPF_REG_X);
406 
407                 /* All programs must keep CTX in callee saved BPF_REG_CTX.
408                  * In eBPF case it's done by the compiler, here we need to
409                  * do this ourself. Initial CTX is present in BPF_REG_ARG1.
410                  */
411                 *new_insn++ = BPF_MOV64_REG(BPF_REG_CTX, BPF_REG_ARG1);
412         } else {
413                 new_insn += 3;
414         }
415 
416         for (i = 0; i < len; fp++, i++) {
417                 struct bpf_insn tmp_insns[6] = { };
418                 struct bpf_insn *insn = tmp_insns;
419 
420                 if (addrs)
421                         addrs[i] = new_insn - first_insn;
422 
423                 switch (fp->code) {
424                 /* All arithmetic insns and skb loads map as-is. */
425                 case BPF_ALU | BPF_ADD | BPF_X:
426                 case BPF_ALU | BPF_ADD | BPF_K:
427                 case BPF_ALU | BPF_SUB | BPF_X:
428                 case BPF_ALU | BPF_SUB | BPF_K:
429                 case BPF_ALU | BPF_AND | BPF_X:
430                 case BPF_ALU | BPF_AND | BPF_K:
431                 case BPF_ALU | BPF_OR | BPF_X:
432                 case BPF_ALU | BPF_OR | BPF_K:
433                 case BPF_ALU | BPF_LSH | BPF_X:
434                 case BPF_ALU | BPF_LSH | BPF_K:
435                 case BPF_ALU | BPF_RSH | BPF_X:
436                 case BPF_ALU | BPF_RSH | BPF_K:
437                 case BPF_ALU | BPF_XOR | BPF_X:
438                 case BPF_ALU | BPF_XOR | BPF_K:
439                 case BPF_ALU | BPF_MUL | BPF_X:
440                 case BPF_ALU | BPF_MUL | BPF_K:
441                 case BPF_ALU | BPF_DIV | BPF_X:
442                 case BPF_ALU | BPF_DIV | BPF_K:
443                 case BPF_ALU | BPF_MOD | BPF_X:
444                 case BPF_ALU | BPF_MOD | BPF_K:
445                 case BPF_ALU | BPF_NEG:
446                 case BPF_LD | BPF_ABS | BPF_W:
447                 case BPF_LD | BPF_ABS | BPF_H:
448                 case BPF_LD | BPF_ABS | BPF_B:
449                 case BPF_LD | BPF_IND | BPF_W:
450                 case BPF_LD | BPF_IND | BPF_H:
451                 case BPF_LD | BPF_IND | BPF_B:
452                         /* Check for overloaded BPF extension and
453                          * directly convert it if found, otherwise
454                          * just move on with mapping.
455                          */
456                         if (BPF_CLASS(fp->code) == BPF_LD &&
457                             BPF_MODE(fp->code) == BPF_ABS &&
458                             convert_bpf_extensions(fp, &insn))
459                                 break;
460 
461                         *insn = BPF_RAW_INSN(fp->code, BPF_REG_A, BPF_REG_X, 0, fp->k);
462                         break;
463 
464                 /* Jump transformation cannot use BPF block macros
465                  * everywhere as offset calculation and target updates
466                  * require a bit more work than the rest, i.e. jump
467                  * opcodes map as-is, but offsets need adjustment.
468                  */
469 
470 #define BPF_EMIT_JMP                                                    \
471         do {                                                            \
472                 if (target >= len || target < 0)                        \
473                         goto err;                                       \
474                 insn->off = addrs ? addrs[target] - addrs[i] - 1 : 0;   \
475                 /* Adjust pc relative offset for 2nd or 3rd insn. */    \
476                 insn->off -= insn - tmp_insns;                          \
477         } while (0)
478 
479                 case BPF_JMP | BPF_JA:
480                         target = i + fp->k + 1;
481                         insn->code = fp->code;
482                         BPF_EMIT_JMP;
483                         break;
484 
485                 case BPF_JMP | BPF_JEQ | BPF_K:
486                 case BPF_JMP | BPF_JEQ | BPF_X:
487                 case BPF_JMP | BPF_JSET | BPF_K:
488                 case BPF_JMP | BPF_JSET | BPF_X:
489                 case BPF_JMP | BPF_JGT | BPF_K:
490                 case BPF_JMP | BPF_JGT | BPF_X:
491                 case BPF_JMP | BPF_JGE | BPF_K:
492                 case BPF_JMP | BPF_JGE | BPF_X:
493                         if (BPF_SRC(fp->code) == BPF_K && (int) fp->k < 0) {
494                                 /* BPF immediates are signed, zero extend
495                                  * immediate into tmp register and use it
496                                  * in compare insn.
497                                  */
498                                 *insn++ = BPF_MOV32_IMM(BPF_REG_TMP, fp->k);
499 
500                                 insn->dst_reg = BPF_REG_A;
501                                 insn->src_reg = BPF_REG_TMP;
502                                 bpf_src = BPF_X;
503                         } else {
504                                 insn->dst_reg = BPF_REG_A;
505                                 insn->imm = fp->k;
506                                 bpf_src = BPF_SRC(fp->code);
507                                 insn->src_reg = bpf_src == BPF_X ? BPF_REG_X : 0;
508                         }
509 
510                         /* Common case where 'jump_false' is next insn. */
511                         if (fp->jf == 0) {
512                                 insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
513                                 target = i + fp->jt + 1;
514                                 BPF_EMIT_JMP;
515                                 break;
516                         }
517 
518                         /* Convert some jumps when 'jump_true' is next insn. */
519                         if (fp->jt == 0) {
520                                 switch (BPF_OP(fp->code)) {
521                                 case BPF_JEQ:
522                                         insn->code = BPF_JMP | BPF_JNE | bpf_src;
523                                         break;
524                                 case BPF_JGT:
525                                         insn->code = BPF_JMP | BPF_JLE | bpf_src;
526                                         break;
527                                 case BPF_JGE:
528                                         insn->code = BPF_JMP | BPF_JLT | bpf_src;
529                                         break;
530                                 default:
531                                         goto jmp_rest;
532                                 }
533 
534                                 target = i + fp->jf + 1;
535                                 BPF_EMIT_JMP;
536                                 break;
537                         }
538 jmp_rest:
539                         /* Other jumps are mapped into two insns: Jxx and JA. */
540                         target = i + fp->jt + 1;
541                         insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
542                         BPF_EMIT_JMP;
543                         insn++;
544 
545                         insn->code = BPF_JMP | BPF_JA;
546                         target = i + fp->jf + 1;
547                         BPF_EMIT_JMP;
548                         break;
549 
550                 /* ldxb 4 * ([14] & 0xf) is remaped into 6 insns. */
551                 case BPF_LDX | BPF_MSH | BPF_B:
552                         /* tmp = A */
553                         *insn++ = BPF_MOV64_REG(BPF_REG_TMP, BPF_REG_A);
554                         /* A = BPF_R0 = *(u8 *) (skb->data + K) */
555                         *insn++ = BPF_LD_ABS(BPF_B, fp->k);
556                         /* A &= 0xf */
557                         *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_A, 0xf);
558                         /* A <<= 2 */
559                         *insn++ = BPF_ALU32_IMM(BPF_LSH, BPF_REG_A, 2);
560                         /* X = A */
561                         *insn++ = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
562                         /* A = tmp */
563                         *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_TMP);
564                         break;
565 
566                 /* RET_K is remaped into 2 insns. RET_A case doesn't need an
567                  * extra mov as BPF_REG_0 is already mapped into BPF_REG_A.
568                  */
569                 case BPF_RET | BPF_A:
570                 case BPF_RET | BPF_K:
571                         if (BPF_RVAL(fp->code) == BPF_K)
572                                 *insn++ = BPF_MOV32_RAW(BPF_K, BPF_REG_0,
573                                                         0, fp->k);
574                         *insn = BPF_EXIT_INSN();
575                         break;
576 
577                 /* Store to stack. */
578                 case BPF_ST:
579                 case BPF_STX:
580                         stack_off = fp->k * 4  + 4;
581                         *insn = BPF_STX_MEM(BPF_W, BPF_REG_FP, BPF_CLASS(fp->code) ==
582                                             BPF_ST ? BPF_REG_A : BPF_REG_X,
583                                             -stack_off);
584                         /* check_load_and_stores() verifies that classic BPF can
585                          * load from stack only after write, so tracking
586                          * stack_depth for ST|STX insns is enough
587                          */
588                         if (new_prog && new_prog->aux->stack_depth < stack_off)
589                                 new_prog->aux->stack_depth = stack_off;
590                         break;
591 
592                 /* Load from stack. */
593                 case BPF_LD | BPF_MEM:
594                 case BPF_LDX | BPF_MEM:
595                         stack_off = fp->k * 4  + 4;
596                         *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD  ?
597                                             BPF_REG_A : BPF_REG_X, BPF_REG_FP,
598                                             -stack_off);
599                         break;
600 
601                 /* A = K or X = K */
602                 case BPF_LD | BPF_IMM:
603                 case BPF_LDX | BPF_IMM:
604                         *insn = BPF_MOV32_IMM(BPF_CLASS(fp->code) == BPF_LD ?
605                                               BPF_REG_A : BPF_REG_X, fp->k);
606                         break;
607 
608                 /* X = A */
609                 case BPF_MISC | BPF_TAX:
610                         *insn = BPF_MOV64_REG(BPF_REG_X, BPF_REG_A);
611                         break;
612 
613                 /* A = X */
614                 case BPF_MISC | BPF_TXA:
615                         *insn = BPF_MOV64_REG(BPF_REG_A, BPF_REG_X);
616                         break;
617 
618                 /* A = skb->len or X = skb->len */
619                 case BPF_LD | BPF_W | BPF_LEN:
620                 case BPF_LDX | BPF_W | BPF_LEN:
621                         *insn = BPF_LDX_MEM(BPF_W, BPF_CLASS(fp->code) == BPF_LD ?
622                                             BPF_REG_A : BPF_REG_X, BPF_REG_CTX,
623                                             offsetof(struct sk_buff, len));
624                         break;
625 
626                 /* Access seccomp_data fields. */
627                 case BPF_LDX | BPF_ABS | BPF_W:
628                         /* A = *(u32 *) (ctx + K) */
629                         *insn = BPF_LDX_MEM(BPF_W, BPF_REG_A, BPF_REG_CTX, fp->k);
630                         break;
631 
632                 /* Unknown instruction. */
633                 default:
634                         goto err;
635                 }
636 
637                 insn++;
638                 if (new_prog)
639                         memcpy(new_insn, tmp_insns,
640                                sizeof(*insn) * (insn - tmp_insns));
641                 new_insn += insn - tmp_insns;
642         }
643 
644         if (!new_prog) {
645                 /* Only calculating new length. */
646                 *new_len = new_insn - first_insn;
647                 return 0;
648         }
649 
650         pass++;
651         if (new_flen != new_insn - first_insn) {
652                 new_flen = new_insn - first_insn;
653                 if (pass > 2)
654                         goto err;
655                 goto do_pass;
656         }
657 
658         kfree(addrs);
659         BUG_ON(*new_len != new_flen);
660         return 0;
661 err:
662         kfree(addrs);
663         return -EINVAL;
664 }
665 
666 /* Security:
667  *
668  * As we dont want to clear mem[] array for each packet going through
669  * __bpf_prog_run(), we check that filter loaded by user never try to read
670  * a cell if not previously written, and we check all branches to be sure
671  * a malicious user doesn't try to abuse us.
672  */
673 static int check_load_and_stores(const struct sock_filter *filter, int flen)
674 {
675         u16 *masks, memvalid = 0; /* One bit per cell, 16 cells */
676         int pc, ret = 0;
677 
678         BUILD_BUG_ON(BPF_MEMWORDS > 16);
679 
680         masks = kmalloc_array(flen, sizeof(*masks), GFP_KERNEL);
681         if (!masks)
682                 return -ENOMEM;
683 
684         memset(masks, 0xff, flen * sizeof(*masks));
685 
686         for (pc = 0; pc < flen; pc++) {
687                 memvalid &= masks[pc];
688 
689                 switch (filter[pc].code) {
690                 case BPF_ST:
691                 case BPF_STX:
692                         memvalid |= (1 << filter[pc].k);
693                         break;
694                 case BPF_LD | BPF_MEM:
695                 case BPF_LDX | BPF_MEM:
696                         if (!(memvalid & (1 << filter[pc].k))) {
697                                 ret = -EINVAL;
698                                 goto error;
699                         }
700                         break;
701                 case BPF_JMP | BPF_JA:
702                         /* A jump must set masks on target */
703                         masks[pc + 1 + filter[pc].k] &= memvalid;
704                         memvalid = ~0;
705                         break;
706                 case BPF_JMP | BPF_JEQ | BPF_K:
707                 case BPF_JMP | BPF_JEQ | BPF_X:
708                 case BPF_JMP | BPF_JGE | BPF_K:
709                 case BPF_JMP | BPF_JGE | BPF_X:
710                 case BPF_JMP | BPF_JGT | BPF_K:
711                 case BPF_JMP | BPF_JGT | BPF_X:
712                 case BPF_JMP | BPF_JSET | BPF_K:
713                 case BPF_JMP | BPF_JSET | BPF_X:
714                         /* A jump must set masks on targets */
715                         masks[pc + 1 + filter[pc].jt] &= memvalid;
716                         masks[pc + 1 + filter[pc].jf] &= memvalid;
717                         memvalid = ~0;
718                         break;
719                 }
720         }
721 error:
722         kfree(masks);
723         return ret;
724 }
725 
726 static bool chk_code_allowed(u16 code_to_probe)
727 {
728         static const bool codes[] = {
729                 /* 32 bit ALU operations */
730                 [BPF_ALU | BPF_ADD | BPF_K] = true,
731                 [BPF_ALU | BPF_ADD | BPF_X] = true,
732                 [BPF_ALU | BPF_SUB | BPF_K] = true,
733                 [BPF_ALU | BPF_SUB | BPF_X] = true,
734                 [BPF_ALU | BPF_MUL | BPF_K] = true,
735                 [BPF_ALU | BPF_MUL | BPF_X] = true,
736                 [BPF_ALU | BPF_DIV | BPF_K] = true,
737                 [BPF_ALU | BPF_DIV | BPF_X] = true,
738                 [BPF_ALU | BPF_MOD | BPF_K] = true,
739                 [BPF_ALU | BPF_MOD | BPF_X] = true,
740                 [BPF_ALU | BPF_AND | BPF_K] = true,
741                 [BPF_ALU | BPF_AND | BPF_X] = true,
742                 [BPF_ALU | BPF_OR | BPF_K] = true,
743                 [BPF_ALU | BPF_OR | BPF_X] = true,
744                 [BPF_ALU | BPF_XOR | BPF_K] = true,
745                 [BPF_ALU | BPF_XOR | BPF_X] = true,
746                 [BPF_ALU | BPF_LSH | BPF_K] = true,
747                 [BPF_ALU | BPF_LSH | BPF_X] = true,
748                 [BPF_ALU | BPF_RSH | BPF_K] = true,
749                 [BPF_ALU | BPF_RSH | BPF_X] = true,
750                 [BPF_ALU | BPF_NEG] = true,
751                 /* Load instructions */
752                 [BPF_LD | BPF_W | BPF_ABS] = true,
753                 [BPF_LD | BPF_H | BPF_ABS] = true,
754                 [BPF_LD | BPF_B | BPF_ABS] = true,
755                 [BPF_LD | BPF_W | BPF_LEN] = true,
756                 [BPF_LD | BPF_W | BPF_IND] = true,
757                 [BPF_LD | BPF_H | BPF_IND] = true,
758                 [BPF_LD | BPF_B | BPF_IND] = true,
759                 [BPF_LD | BPF_IMM] = true,
760                 [BPF_LD | BPF_MEM] = true,
761                 [BPF_LDX | BPF_W | BPF_LEN] = true,
762                 [BPF_LDX | BPF_B | BPF_MSH] = true,
763                 [BPF_LDX | BPF_IMM] = true,
764                 [BPF_LDX | BPF_MEM] = true,
765                 /* Store instructions */
766                 [BPF_ST] = true,
767                 [BPF_STX] = true,
768                 /* Misc instructions */
769                 [BPF_MISC | BPF_TAX] = true,
770                 [BPF_MISC | BPF_TXA] = true,
771                 /* Return instructions */
772                 [BPF_RET | BPF_K] = true,
773                 [BPF_RET | BPF_A] = true,
774                 /* Jump instructions */
775                 [BPF_JMP | BPF_JA] = true,
776                 [BPF_JMP | BPF_JEQ | BPF_K] = true,
777                 [BPF_JMP | BPF_JEQ | BPF_X] = true,
778                 [BPF_JMP | BPF_JGE | BPF_K] = true,
779                 [BPF_JMP | BPF_JGE | BPF_X] = true,
780                 [BPF_JMP | BPF_JGT | BPF_K] = true,
781                 [BPF_JMP | BPF_JGT | BPF_X] = true,
782                 [BPF_JMP | BPF_JSET | BPF_K] = true,
783                 [BPF_JMP | BPF_JSET | BPF_X] = true,
784         };
785 
786         if (code_to_probe >= ARRAY_SIZE(codes))
787                 return false;
788 
789         return codes[code_to_probe];
790 }
791 
792 static bool bpf_check_basics_ok(const struct sock_filter *filter,
793                                 unsigned int flen)
794 {
795         if (filter == NULL)
796                 return false;
797         if (flen == 0 || flen > BPF_MAXINSNS)
798                 return false;
799 
800         return true;
801 }
802 
803 /**
804  *      bpf_check_classic - verify socket filter code
805  *      @filter: filter to verify
806  *      @flen: length of filter
807  *
808  * Check the user's filter code. If we let some ugly
809  * filter code slip through kaboom! The filter must contain
810  * no references or jumps that are out of range, no illegal
811  * instructions, and must end with a RET instruction.
812  *
813  * All jumps are forward as they are not signed.
814  *
815  * Returns 0 if the rule set is legal or -EINVAL if not.
816  */
817 static int bpf_check_classic(const struct sock_filter *filter,
818                              unsigned int flen)
819 {
820         bool anc_found;
821         int pc;
822 
823         /* Check the filter code now */
824         for (pc = 0; pc < flen; pc++) {
825                 const struct sock_filter *ftest = &filter[pc];
826 
827                 /* May we actually operate on this code? */
828                 if (!chk_code_allowed(ftest->code))
829                         return -EINVAL;
830 
831                 /* Some instructions need special checks */
832                 switch (ftest->code) {
833                 case BPF_ALU | BPF_DIV | BPF_K:
834                 case BPF_ALU | BPF_MOD | BPF_K:
835                         /* Check for division by zero */
836                         if (ftest->k == 0)
837                                 return -EINVAL;
838                         break;
839                 case BPF_ALU | BPF_LSH | BPF_K:
840                 case BPF_ALU | BPF_RSH | BPF_K:
841                         if (ftest->k >= 32)
842                                 return -EINVAL;
843                         break;
844                 case BPF_LD | BPF_MEM:
845                 case BPF_LDX | BPF_MEM:
846                 case BPF_ST:
847                 case BPF_STX:
848                         /* Check for invalid memory addresses */
849                         if (ftest->k >= BPF_MEMWORDS)
850                                 return -EINVAL;
851                         break;
852                 case BPF_JMP | BPF_JA:
853                         /* Note, the large ftest->k might cause loops.
854                          * Compare this with conditional jumps below,
855                          * where offsets are limited. --ANK (981016)
856                          */
857                         if (ftest->k >= (unsigned int)(flen - pc - 1))
858                                 return -EINVAL;
859                         break;
860                 case BPF_JMP | BPF_JEQ | BPF_K:
861                 case BPF_JMP | BPF_JEQ | BPF_X:
862                 case BPF_JMP | BPF_JGE | BPF_K:
863                 case BPF_JMP | BPF_JGE | BPF_X:
864                 case BPF_JMP | BPF_JGT | BPF_K:
865                 case BPF_JMP | BPF_JGT | BPF_X:
866                 case BPF_JMP | BPF_JSET | BPF_K:
867                 case BPF_JMP | BPF_JSET | BPF_X:
868                         /* Both conditionals must be safe */
869                         if (pc + ftest->jt + 1 >= flen ||
870                             pc + ftest->jf + 1 >= flen)
871                                 return -EINVAL;
872                         break;
873                 case BPF_LD | BPF_W | BPF_ABS:
874                 case BPF_LD | BPF_H | BPF_ABS:
875                 case BPF_LD | BPF_B | BPF_ABS:
876                         anc_found = false;
877                         if (bpf_anc_helper(ftest) & BPF_ANC)
878                                 anc_found = true;
879                         /* Ancillary operation unknown or unsupported */
880                         if (anc_found == false && ftest->k >= SKF_AD_OFF)
881                                 return -EINVAL;
882                 }
883         }
884 
885         /* Last instruction must be a RET code */
886         switch (filter[flen - 1].code) {
887         case BPF_RET | BPF_K:
888         case BPF_RET | BPF_A:
889                 return check_load_and_stores(filter, flen);
890         }
891 
892         return -EINVAL;
893 }
894 
895 static int bpf_prog_store_orig_filter(struct bpf_prog *fp,
896                                       const struct sock_fprog *fprog)
897 {
898         unsigned int fsize = bpf_classic_proglen(fprog);
899         struct sock_fprog_kern *fkprog;
900 
901         fp->orig_prog = kmalloc(sizeof(*fkprog), GFP_KERNEL);
902         if (!fp->orig_prog)
903                 return -ENOMEM;
904 
905         fkprog = fp->orig_prog;
906         fkprog->len = fprog->len;
907 
908         fkprog->filter = kmemdup(fp->insns, fsize,
909                                  GFP_KERNEL | __GFP_NOWARN);
910         if (!fkprog->filter) {
911                 kfree(fp->orig_prog);
912                 return -ENOMEM;
913         }
914 
915         return 0;
916 }
917 
918 static void bpf_release_orig_filter(struct bpf_prog *fp)
919 {
920         struct sock_fprog_kern *fprog = fp->orig_prog;
921 
922         if (fprog) {
923                 kfree(fprog->filter);
924                 kfree(fprog);
925         }
926 }
927 
928 static void __bpf_prog_release(struct bpf_prog *prog)
929 {
930         if (prog->type == BPF_PROG_TYPE_SOCKET_FILTER) {
931                 bpf_prog_put(prog);
932         } else {
933                 bpf_release_orig_filter(prog);
934                 bpf_prog_free(prog);
935         }
936 }
937 
938 static void __sk_filter_release(struct sk_filter *fp)
939 {
940         __bpf_prog_release(fp->prog);
941         kfree(fp);
942 }
943 
944 /**
945  *      sk_filter_release_rcu - Release a socket filter by rcu_head
946  *      @rcu: rcu_head that contains the sk_filter to free
947  */
948 static void sk_filter_release_rcu(struct rcu_head *rcu)
949 {
950         struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu);
951 
952         __sk_filter_release(fp);
953 }
954 
955 /**
956  *      sk_filter_release - release a socket filter
957  *      @fp: filter to remove
958  *
959  *      Remove a filter from a socket and release its resources.
960  */
961 static void sk_filter_release(struct sk_filter *fp)
962 {
963         if (refcount_dec_and_test(&fp->refcnt))
964                 call_rcu(&fp->rcu, sk_filter_release_rcu);
965 }
966 
967 void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
968 {
969         u32 filter_size = bpf_prog_size(fp->prog->len);
970 
971         atomic_sub(filter_size, &sk->sk_omem_alloc);
972         sk_filter_release(fp);
973 }
974 
975 /* try to charge the socket memory if there is space available
976  * return true on success
977  */
978 static bool __sk_filter_charge(struct sock *sk, struct sk_filter *fp)
979 {
980         u32 filter_size = bpf_prog_size(fp->prog->len);
981 
982         /* same check as in sock_kmalloc() */
983         if (filter_size <= sysctl_optmem_max &&
984             atomic_read(&sk->sk_omem_alloc) + filter_size < sysctl_optmem_max) {
985                 atomic_add(filter_size, &sk->sk_omem_alloc);
986                 return true;
987         }
988         return false;
989 }
990 
991 bool sk_filter_charge(struct sock *sk, struct sk_filter *fp)
992 {
993         if (!refcount_inc_not_zero(&fp->refcnt))
994                 return false;
995 
996         if (!__sk_filter_charge(sk, fp)) {
997                 sk_filter_release(fp);
998                 return false;
999         }
1000         return true;
1001 }
1002 
1003 static struct bpf_prog *bpf_migrate_filter(struct bpf_prog *fp)
1004 {
1005         struct sock_filter *old_prog;
1006         struct bpf_prog *old_fp;
1007         int err, new_len, old_len = fp->len;
1008 
1009         /* We are free to overwrite insns et al right here as it
1010          * won't be used at this point in time anymore internally
1011          * after the migration to the internal BPF instruction
1012          * representation.
1013          */
1014         BUILD_BUG_ON(sizeof(struct sock_filter) !=
1015                      sizeof(struct bpf_insn));
1016 
1017         /* Conversion cannot happen on overlapping memory areas,
1018          * so we need to keep the user BPF around until the 2nd
1019          * pass. At this time, the user BPF is stored in fp->insns.
1020          */
1021         old_prog = kmemdup(fp->insns, old_len * sizeof(struct sock_filter),
1022                            GFP_KERNEL | __GFP_NOWARN);
1023         if (!old_prog) {
1024                 err = -ENOMEM;
1025                 goto out_err;
1026         }
1027 
1028         /* 1st pass: calculate the new program length. */
1029         err = bpf_convert_filter(old_prog, old_len, NULL, &new_len);
1030         if (err)
1031                 goto out_err_free;
1032 
1033         /* Expand fp for appending the new filter representation. */
1034         old_fp = fp;
1035         fp = bpf_prog_realloc(old_fp, bpf_prog_size(new_len), 0);
1036         if (!fp) {
1037                 /* The old_fp is still around in case we couldn't
1038                  * allocate new memory, so uncharge on that one.
1039                  */
1040                 fp = old_fp;
1041                 err = -ENOMEM;
1042                 goto out_err_free;
1043         }
1044 
1045         fp->len = new_len;
1046 
1047         /* 2nd pass: remap sock_filter insns into bpf_insn insns. */
1048         err = bpf_convert_filter(old_prog, old_len, fp, &new_len);
1049         if (err)
1050                 /* 2nd bpf_convert_filter() can fail only if it fails
1051                  * to allocate memory, remapping must succeed. Note,
1052                  * that at this time old_fp has already been released
1053                  * by krealloc().
1054                  */
1055                 goto out_err_free;
1056 
1057         /* We are guaranteed to never error here with cBPF to eBPF
1058          * transitions, since there's no issue with type compatibility
1059          * checks on program arrays.
1060          */
1061         fp = bpf_prog_select_runtime(fp, &err);
1062 
1063         kfree(old_prog);
1064         return fp;
1065 
1066 out_err_free:
1067         kfree(old_prog);
1068 out_err:
1069         __bpf_prog_release(fp);
1070         return ERR_PTR(err);
1071 }
1072 
1073 static struct bpf_prog *bpf_prepare_filter(struct bpf_prog *fp,
1074                                            bpf_aux_classic_check_t trans)
1075 {
1076         int err;
1077 
1078         fp->bpf_func = NULL;
1079         fp->jited = 0;
1080 
1081         err = bpf_check_classic(fp->insns, fp->len);
1082         if (err) {
1083                 __bpf_prog_release(fp);
1084                 return ERR_PTR(err);
1085         }
1086 
1087         /* There might be additional checks and transformations
1088          * needed on classic filters, f.e. in case of seccomp.
1089          */
1090         if (trans) {
1091                 err = trans(fp->insns, fp->len);
1092                 if (err) {
1093                         __bpf_prog_release(fp);
1094                         return ERR_PTR(err);
1095                 }
1096         }
1097 
1098         /* Probe if we can JIT compile the filter and if so, do
1099          * the compilation of the filter.
1100          */
1101         bpf_jit_compile(fp);
1102 
1103         /* JIT compiler couldn't process this filter, so do the
1104          * internal BPF translation for the optimized interpreter.
1105          */
1106         if (!fp->jited)
1107                 fp = bpf_migrate_filter(fp);
1108 
1109         return fp;
1110 }
1111 
1112 /**
1113  *      bpf_prog_create - create an unattached filter
1114  *      @pfp: the unattached filter that is created
1115  *      @fprog: the filter program
1116  *
1117  * Create a filter independent of any socket. We first run some
1118  * sanity checks on it to make sure it does not explode on us later.
1119  * If an error occurs or there is insufficient memory for the filter
1120  * a negative errno code is returned. On success the return is zero.
1121  */
1122 int bpf_prog_create(struct bpf_prog **pfp, struct sock_fprog_kern *fprog)
1123 {
1124         unsigned int fsize = bpf_classic_proglen(fprog);
1125         struct bpf_prog *fp;
1126 
1127         /* Make sure new filter is there and in the right amounts. */
1128         if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1129                 return -EINVAL;
1130 
1131         fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1132         if (!fp)
1133                 return -ENOMEM;
1134 
1135         memcpy(fp->insns, fprog->filter, fsize);
1136 
1137         fp->len = fprog->len;
1138         /* Since unattached filters are not copied back to user
1139          * space through sk_get_filter(), we do not need to hold
1140          * a copy here, and can spare us the work.
1141          */
1142         fp->orig_prog = NULL;
1143 
1144         /* bpf_prepare_filter() already takes care of freeing
1145          * memory in case something goes wrong.
1146          */
1147         fp = bpf_prepare_filter(fp, NULL);
1148         if (IS_ERR(fp))
1149                 return PTR_ERR(fp);
1150 
1151         *pfp = fp;
1152         return 0;
1153 }
1154 EXPORT_SYMBOL_GPL(bpf_prog_create);
1155 
1156 /**
1157  *      bpf_prog_create_from_user - create an unattached filter from user buffer
1158  *      @pfp: the unattached filter that is created
1159  *      @fprog: the filter program
1160  *      @trans: post-classic verifier transformation handler
1161  *      @save_orig: save classic BPF program
1162  *
1163  * This function effectively does the same as bpf_prog_create(), only
1164  * that it builds up its insns buffer from user space provided buffer.
1165  * It also allows for passing a bpf_aux_classic_check_t handler.
1166  */
1167 int bpf_prog_create_from_user(struct bpf_prog **pfp, struct sock_fprog *fprog,
1168                               bpf_aux_classic_check_t trans, bool save_orig)
1169 {
1170         unsigned int fsize = bpf_classic_proglen(fprog);
1171         struct bpf_prog *fp;
1172         int err;
1173 
1174         /* Make sure new filter is there and in the right amounts. */
1175         if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1176                 return -EINVAL;
1177 
1178         fp = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1179         if (!fp)
1180                 return -ENOMEM;
1181 
1182         if (copy_from_user(fp->insns, fprog->filter, fsize)) {
1183                 __bpf_prog_free(fp);
1184                 return -EFAULT;
1185         }
1186 
1187         fp->len = fprog->len;
1188         fp->orig_prog = NULL;
1189 
1190         if (save_orig) {
1191                 err = bpf_prog_store_orig_filter(fp, fprog);
1192                 if (err) {
1193                         __bpf_prog_free(fp);
1194                         return -ENOMEM;
1195                 }
1196         }
1197 
1198         /* bpf_prepare_filter() already takes care of freeing
1199          * memory in case something goes wrong.
1200          */
1201         fp = bpf_prepare_filter(fp, trans);
1202         if (IS_ERR(fp))
1203                 return PTR_ERR(fp);
1204 
1205         *pfp = fp;
1206         return 0;
1207 }
1208 EXPORT_SYMBOL_GPL(bpf_prog_create_from_user);
1209 
1210 void bpf_prog_destroy(struct bpf_prog *fp)
1211 {
1212         __bpf_prog_release(fp);
1213 }
1214 EXPORT_SYMBOL_GPL(bpf_prog_destroy);
1215 
1216 static int __sk_attach_prog(struct bpf_prog *prog, struct sock *sk)
1217 {
1218         struct sk_filter *fp, *old_fp;
1219 
1220         fp = kmalloc(sizeof(*fp), GFP_KERNEL);
1221         if (!fp)
1222                 return -ENOMEM;
1223 
1224         fp->prog = prog;
1225 
1226         if (!__sk_filter_charge(sk, fp)) {
1227                 kfree(fp);
1228                 return -ENOMEM;
1229         }
1230         refcount_set(&fp->refcnt, 1);
1231 
1232         old_fp = rcu_dereference_protected(sk->sk_filter,
1233                                            lockdep_sock_is_held(sk));
1234         rcu_assign_pointer(sk->sk_filter, fp);
1235 
1236         if (old_fp)
1237                 sk_filter_uncharge(sk, old_fp);
1238 
1239         return 0;
1240 }
1241 
1242 static int __reuseport_attach_prog(struct bpf_prog *prog, struct sock *sk)
1243 {
1244         struct bpf_prog *old_prog;
1245         int err;
1246 
1247         if (bpf_prog_size(prog->len) > sysctl_optmem_max)
1248                 return -ENOMEM;
1249 
1250         if (sk_unhashed(sk) && sk->sk_reuseport) {
1251                 err = reuseport_alloc(sk);
1252                 if (err)
1253                         return err;
1254         } else if (!rcu_access_pointer(sk->sk_reuseport_cb)) {
1255                 /* The socket wasn't bound with SO_REUSEPORT */
1256                 return -EINVAL;
1257         }
1258 
1259         old_prog = reuseport_attach_prog(sk, prog);
1260         if (old_prog)
1261                 bpf_prog_destroy(old_prog);
1262 
1263         return 0;
1264 }
1265 
1266 static
1267 struct bpf_prog *__get_filter(struct sock_fprog *fprog, struct sock *sk)
1268 {
1269         unsigned int fsize = bpf_classic_proglen(fprog);
1270         struct bpf_prog *prog;
1271         int err;
1272 
1273         if (sock_flag(sk, SOCK_FILTER_LOCKED))
1274                 return ERR_PTR(-EPERM);
1275 
1276         /* Make sure new filter is there and in the right amounts. */
1277         if (!bpf_check_basics_ok(fprog->filter, fprog->len))
1278                 return ERR_PTR(-EINVAL);
1279 
1280         prog = bpf_prog_alloc(bpf_prog_size(fprog->len), 0);
1281         if (!prog)
1282                 return ERR_PTR(-ENOMEM);
1283 
1284         if (copy_from_user(prog->insns, fprog->filter, fsize)) {
1285                 __bpf_prog_free(prog);
1286                 return ERR_PTR(-EFAULT);
1287         }
1288 
1289         prog->len = fprog->len;
1290 
1291         err = bpf_prog_store_orig_filter(prog, fprog);
1292         if (err) {
1293                 __bpf_prog_free(prog);
1294                 return ERR_PTR(-ENOMEM);
1295         }
1296 
1297         /* bpf_prepare_filter() already takes care of freeing
1298          * memory in case something goes wrong.
1299          */
1300         return bpf_prepare_filter(prog, NULL);
1301 }
1302 
1303 /**
1304  *      sk_attach_filter - attach a socket filter
1305  *      @fprog: the filter program
1306  *      @sk: the socket to use
1307  *
1308  * Attach the user's filter code. We first run some sanity checks on
1309  * it to make sure it does not explode on us later. If an error
1310  * occurs or there is insufficient memory for the filter a negative
1311  * errno code is returned. On success the return is zero.
1312  */
1313 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk)
1314 {
1315         struct bpf_prog *prog = __get_filter(fprog, sk);
1316         int err;
1317 
1318         if (IS_ERR(prog))
1319                 return PTR_ERR(prog);
1320 
1321         err = __sk_attach_prog(prog, sk);
1322         if (err < 0) {
1323                 __bpf_prog_release(prog);
1324                 return err;
1325         }
1326 
1327         return 0;
1328 }
1329 EXPORT_SYMBOL_GPL(sk_attach_filter);
1330 
1331 int sk_reuseport_attach_filter(struct sock_fprog *fprog, struct sock *sk)
1332 {
1333         struct bpf_prog *prog = __get_filter(fprog, sk);
1334         int err;
1335 
1336         if (IS_ERR(prog))
1337                 return PTR_ERR(prog);
1338 
1339         err = __reuseport_attach_prog(prog, sk);
1340         if (err < 0) {
1341                 __bpf_prog_release(prog);
1342                 return err;
1343         }
1344 
1345         return 0;
1346 }
1347 
1348 static struct bpf_prog *__get_bpf(u32 ufd, struct sock *sk)
1349 {
1350         if (sock_flag(sk, SOCK_FILTER_LOCKED))
1351                 return ERR_PTR(-EPERM);
1352 
1353         return bpf_prog_get_type(ufd, BPF_PROG_TYPE_SOCKET_FILTER);
1354 }
1355 
1356 int sk_attach_bpf(u32 ufd, struct sock *sk)
1357 {
1358         struct bpf_prog *prog = __get_bpf(ufd, sk);
1359         int err;
1360 
1361         if (IS_ERR(prog))
1362                 return PTR_ERR(prog);
1363 
1364         err = __sk_attach_prog(prog, sk);
1365         if (err < 0) {
1366                 bpf_prog_put(prog);
1367                 return err;
1368         }
1369 
1370         return 0;
1371 }
1372 
1373 int sk_reuseport_attach_bpf(u32 ufd, struct sock *sk)
1374 {
1375         struct bpf_prog *prog = __get_bpf(ufd, sk);
1376         int err;
1377 
1378         if (IS_ERR(prog))
1379                 return PTR_ERR(prog);
1380 
1381         err = __reuseport_attach_prog(prog, sk);
1382         if (err < 0) {
1383                 bpf_prog_put(prog);
1384                 return err;
1385         }
1386 
1387         return 0;
1388 }
1389 
1390 struct bpf_scratchpad {
1391         union {
1392                 __be32 diff[MAX_BPF_STACK / sizeof(__be32)];
1393                 u8     buff[MAX_BPF_STACK];
1394         };
1395 };
1396 
1397 static DEFINE_PER_CPU(struct bpf_scratchpad, bpf_sp);
1398 
1399 static inline int __bpf_try_make_writable(struct sk_buff *skb,
1400                                           unsigned int write_len)
1401 {
1402         return skb_ensure_writable(skb, write_len);
1403 }
1404 
1405 static inline int bpf_try_make_writable(struct sk_buff *skb,
1406                                         unsigned int write_len)
1407 {
1408         int err = __bpf_try_make_writable(skb, write_len);
1409 
1410         bpf_compute_data_pointers(skb);
1411         return err;
1412 }
1413 
1414 static int bpf_try_make_head_writable(struct sk_buff *skb)
1415 {
1416         return bpf_try_make_writable(skb, skb_headlen(skb));
1417 }
1418 
1419 static inline void bpf_push_mac_rcsum(struct sk_buff *skb)
1420 {
1421         if (skb_at_tc_ingress(skb))
1422                 skb_postpush_rcsum(skb, skb_mac_header(skb), skb->mac_len);
1423 }
1424 
1425 static inline void bpf_pull_mac_rcsum(struct sk_buff *skb)
1426 {
1427         if (skb_at_tc_ingress(skb))
1428                 skb_postpull_rcsum(skb, skb_mac_header(skb), skb->mac_len);
1429 }
1430 
1431 BPF_CALL_5(bpf_skb_store_bytes, struct sk_buff *, skb, u32, offset,
1432            const void *, from, u32, len, u64, flags)
1433 {
1434         void *ptr;
1435 
1436         if (unlikely(flags & ~(BPF_F_RECOMPUTE_CSUM | BPF_F_INVALIDATE_HASH)))
1437                 return -EINVAL;
1438         if (unlikely(offset > 0xffff))
1439                 return -EFAULT;
1440         if (unlikely(bpf_try_make_writable(skb, offset + len)))
1441                 return -EFAULT;
1442 
1443         ptr = skb->data + offset;
1444         if (flags & BPF_F_RECOMPUTE_CSUM)
1445                 __skb_postpull_rcsum(skb, ptr, len, offset);
1446 
1447         memcpy(ptr, from, len);
1448 
1449         if (flags & BPF_F_RECOMPUTE_CSUM)
1450                 __skb_postpush_rcsum(skb, ptr, len, offset);
1451         if (flags & BPF_F_INVALIDATE_HASH)
1452                 skb_clear_hash(skb);
1453 
1454         return 0;
1455 }
1456 
1457 static const struct bpf_func_proto bpf_skb_store_bytes_proto = {
1458         .func           = bpf_skb_store_bytes,
1459         .gpl_only       = false,
1460         .ret_type       = RET_INTEGER,
1461         .arg1_type      = ARG_PTR_TO_CTX,
1462         .arg2_type      = ARG_ANYTHING,
1463         .arg3_type      = ARG_PTR_TO_MEM,
1464         .arg4_type      = ARG_CONST_SIZE,
1465         .arg5_type      = ARG_ANYTHING,
1466 };
1467 
1468 BPF_CALL_4(bpf_skb_load_bytes, const struct sk_buff *, skb, u32, offset,
1469            void *, to, u32, len)
1470 {
1471         void *ptr;
1472 
1473         if (unlikely(offset > 0xffff))
1474                 goto err_clear;
1475 
1476         ptr = skb_header_pointer(skb, offset, len, to);
1477         if (unlikely(!ptr))
1478                 goto err_clear;
1479         if (ptr != to)
1480                 memcpy(to, ptr, len);
1481 
1482         return 0;
1483 err_clear:
1484         memset(to, 0, len);
1485         return -EFAULT;
1486 }
1487 
1488 static const struct bpf_func_proto bpf_skb_load_bytes_proto = {
1489         .func           = bpf_skb_load_bytes,
1490         .gpl_only       = false,
1491         .ret_type       = RET_INTEGER,
1492         .arg1_type      = ARG_PTR_TO_CTX,
1493         .arg2_type      = ARG_ANYTHING,
1494         .arg3_type      = ARG_PTR_TO_UNINIT_MEM,
1495         .arg4_type      = ARG_CONST_SIZE,
1496 };
1497 
1498 BPF_CALL_2(bpf_skb_pull_data, struct sk_buff *, skb, u32, len)
1499 {
1500         /* Idea is the following: should the needed direct read/write
1501          * test fail during runtime, we can pull in more data and redo
1502          * again, since implicitly, we invalidate previous checks here.
1503          *
1504          * Or, since we know how much we need to make read/writeable,
1505          * this can be done once at the program beginning for direct
1506          * access case. By this we overcome limitations of only current
1507          * headroom being accessible.
1508          */
1509         return bpf_try_make_writable(skb, len ? : skb_headlen(skb));
1510 }
1511 
1512 static const struct bpf_func_proto bpf_skb_pull_data_proto = {
1513         .func           = bpf_skb_pull_data,
1514         .gpl_only       = false,
1515         .ret_type       = RET_INTEGER,
1516         .arg1_type      = ARG_PTR_TO_CTX,
1517         .arg2_type      = ARG_ANYTHING,
1518 };
1519 
1520 BPF_CALL_5(bpf_l3_csum_replace, struct sk_buff *, skb, u32, offset,
1521            u64, from, u64, to, u64, flags)
1522 {
1523         __sum16 *ptr;
1524 
1525         if (unlikely(flags & ~(BPF_F_HDR_FIELD_MASK)))
1526                 return -EINVAL;
1527         if (unlikely(offset > 0xffff || offset & 1))
1528                 return -EFAULT;
1529         if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
1530                 return -EFAULT;
1531 
1532         ptr = (__sum16 *)(skb->data + offset);
1533         switch (flags & BPF_F_HDR_FIELD_MASK) {
1534         case 0:
1535                 if (unlikely(from != 0))
1536                         return -EINVAL;
1537 
1538                 csum_replace_by_diff(ptr, to);
1539                 break;
1540         case 2:
1541                 csum_replace2(ptr, from, to);
1542                 break;
1543         case 4:
1544                 csum_replace4(ptr, from, to);
1545                 break;
1546         default:
1547                 return -EINVAL;
1548         }
1549 
1550         return 0;
1551 }
1552 
1553 static const struct bpf_func_proto bpf_l3_csum_replace_proto = {
1554         .func           = bpf_l3_csum_replace,
1555         .gpl_only       = false,
1556         .ret_type       = RET_INTEGER,
1557         .arg1_type      = ARG_PTR_TO_CTX,
1558         .arg2_type      = ARG_ANYTHING,
1559         .arg3_type      = ARG_ANYTHING,
1560         .arg4_type      = ARG_ANYTHING,
1561         .arg5_type      = ARG_ANYTHING,
1562 };
1563 
1564 BPF_CALL_5(bpf_l4_csum_replace, struct sk_buff *, skb, u32, offset,
1565            u64, from, u64, to, u64, flags)
1566 {
1567         bool is_pseudo = flags & BPF_F_PSEUDO_HDR;
1568         bool is_mmzero = flags & BPF_F_MARK_MANGLED_0;
1569         bool do_mforce = flags & BPF_F_MARK_ENFORCE;
1570         __sum16 *ptr;
1571 
1572         if (unlikely(flags & ~(BPF_F_MARK_MANGLED_0 | BPF_F_MARK_ENFORCE |
1573                                BPF_F_PSEUDO_HDR | BPF_F_HDR_FIELD_MASK)))
1574                 return -EINVAL;
1575         if (unlikely(offset > 0xffff || offset & 1))
1576                 return -EFAULT;
1577         if (unlikely(bpf_try_make_writable(skb, offset + sizeof(*ptr))))
1578                 return -EFAULT;
1579 
1580         ptr = (__sum16 *)(skb->data + offset);
1581         if (is_mmzero && !do_mforce && !*ptr)
1582                 return 0;
1583 
1584         switch (flags & BPF_F_HDR_FIELD_MASK) {
1585         case 0:
1586                 if (unlikely(from != 0))
1587                         return -EINVAL;
1588 
1589                 inet_proto_csum_replace_by_diff(ptr, skb, to, is_pseudo);
1590                 break;
1591         case 2:
1592                 inet_proto_csum_replace2(ptr, skb, from, to, is_pseudo);
1593                 break;
1594         case 4:
1595                 inet_proto_csum_replace4(ptr, skb, from, to, is_pseudo);
1596                 break;
1597         default:
1598                 return -EINVAL;
1599         }
1600 
1601         if (is_mmzero && !*ptr)
1602                 *ptr = CSUM_MANGLED_0;
1603         return 0;
1604 }
1605 
1606 static const struct bpf_func_proto bpf_l4_csum_replace_proto = {
1607         .func           = bpf_l4_csum_replace,
1608         .gpl_only       = false,
1609         .ret_type       = RET_INTEGER,
1610         .arg1_type      = ARG_PTR_TO_CTX,
1611         .arg2_type      = ARG_ANYTHING,
1612         .arg3_type      = ARG_ANYTHING,
1613         .arg4_type      = ARG_ANYTHING,
1614         .arg5_type      = ARG_ANYTHING,
1615 };
1616 
1617 BPF_CALL_5(bpf_csum_diff, __be32 *, from, u32, from_size,
1618            __be32 *, to, u32, to_size, __wsum, seed)
1619 {
1620         struct bpf_scratchpad *sp = this_cpu_ptr(&bpf_sp);
1621         u32 diff_size = from_size + to_size;
1622         int i, j = 0;
1623 
1624         /* This is quite flexible, some examples:
1625          *
1626          * from_size == 0, to_size > 0,  seed := csum --> pushing data
1627          * from_size > 0,  to_size == 0, seed := csum --> pulling data
1628          * from_size > 0,  to_size > 0,  seed := 0    --> diffing data
1629          *
1630          * Even for diffing, from_size and to_size don't need to be equal.
1631          */
1632         if (unlikely(((from_size | to_size) & (sizeof(__be32) - 1)) ||
1633                      diff_size > sizeof(sp->diff)))
1634                 return -EINVAL;
1635 
1636         for (i = 0; i < from_size / sizeof(__be32); i++, j++)
1637                 sp->diff[j] = ~from[i];
1638         for (i = 0; i <   to_size / sizeof(__be32); i++, j++)
1639                 sp->diff[j] = to[i];
1640 
1641         return csum_partial(sp->diff, diff_size, seed);
1642 }
1643 
1644 static const struct bpf_func_proto bpf_csum_diff_proto = {
1645         .func           = bpf_csum_diff,
1646         .gpl_only       = false,
1647         .pkt_access     = true,
1648         .ret_type       = RET_INTEGER,
1649         .arg1_type      = ARG_PTR_TO_MEM_OR_NULL,
1650         .arg2_type      = ARG_CONST_SIZE_OR_ZERO,
1651         .arg3_type      = ARG_PTR_TO_MEM_OR_NULL,
1652         .arg4_type      = ARG_CONST_SIZE_OR_ZERO,
1653         .arg5_type      = ARG_ANYTHING,
1654 };
1655 
1656 BPF_CALL_2(bpf_csum_update, struct sk_buff *, skb, __wsum, csum)
1657 {
1658         /* The interface is to be used in combination with bpf_csum_diff()
1659          * for direct packet writes. csum rotation for alignment as well
1660          * as emulating csum_sub() can be done from the eBPF program.
1661          */
1662         if (skb->ip_summed == CHECKSUM_COMPLETE)
1663                 return (skb->csum = csum_add(skb->csum, csum));
1664 
1665         return -ENOTSUPP;
1666 }
1667 
1668 static const struct bpf_func_proto bpf_csum_update_proto = {
1669         .func           = bpf_csum_update,
1670         .gpl_only       = false,
1671         .ret_type       = RET_INTEGER,
1672         .arg1_type      = ARG_PTR_TO_CTX,
1673         .arg2_type      = ARG_ANYTHING,
1674 };
1675 
1676 static inline int __bpf_rx_skb(struct net_device *dev, struct sk_buff *skb)
1677 {
1678         return dev_forward_skb(dev, skb);
1679 }
1680 
1681 static inline int __bpf_rx_skb_no_mac(struct net_device *dev,
1682                                       struct sk_buff *skb)
1683 {
1684         int ret = ____dev_forward_skb(dev, skb);
1685 
1686         if (likely(!ret)) {
1687                 skb->dev = dev;
1688                 ret = netif_rx(skb);
1689         }
1690 
1691         return ret;
1692 }
1693 
1694 static inline int __bpf_tx_skb(struct net_device *dev, struct sk_buff *skb)
1695 {
1696         int ret;
1697 
1698         if (unlikely(__this_cpu_read(xmit_recursion) > XMIT_RECURSION_LIMIT)) {
1699                 net_crit_ratelimited("bpf: recursion limit reached on datapath, buggy bpf program?\n");
1700                 kfree_skb(skb);
1701                 return -ENETDOWN;
1702         }
1703 
1704         skb->dev = dev;
1705 
1706         __this_cpu_inc(xmit_recursion);
1707         ret = dev_queue_xmit(skb);
1708         __this_cpu_dec(xmit_recursion);
1709 
1710         return ret;
1711 }
1712 
1713 static int __bpf_redirect_no_mac(struct sk_buff *skb, struct net_device *dev,
1714                                  u32 flags)
1715 {
1716         /* skb->mac_len is not set on normal egress */
1717         unsigned int mlen = skb->network_header - skb->mac_header;
1718 
1719         __skb_pull(skb, mlen);
1720 
1721         /* At ingress, the mac header has already been pulled once.
1722          * At egress, skb_pospull_rcsum has to be done in case that
1723          * the skb is originated from ingress (i.e. a forwarded skb)
1724          * to ensure that rcsum starts at net header.
1725          */
1726         if (!skb_at_tc_ingress(skb))
1727                 skb_postpull_rcsum(skb, skb_mac_header(skb), mlen);
1728         skb_pop_mac_header(skb);
1729         skb_reset_mac_len(skb);
1730         return flags & BPF_F_INGRESS ?
1731                __bpf_rx_skb_no_mac(dev, skb) : __bpf_tx_skb(dev, skb);
1732 }
1733 
1734 static int __bpf_redirect_common(struct sk_buff *skb, struct net_device *dev,
1735                                  u32 flags)
1736 {
1737         /* Verify that a link layer header is carried */
1738         if (unlikely(skb->mac_header >= skb->network_header)) {
1739                 kfree_skb(skb);
1740                 return -ERANGE;
1741         }
1742 
1743         bpf_push_mac_rcsum(skb);
1744         return flags & BPF_F_INGRESS ?
1745                __bpf_rx_skb(dev, skb) : __bpf_tx_skb(dev, skb);
1746 }
1747 
1748 static int __bpf_redirect(struct sk_buff *skb, struct net_device *dev,
1749                           u32 flags)
1750 {
1751         if (dev_is_mac_header_xmit(dev))
1752                 return __bpf_redirect_common(skb, dev, flags);
1753         else
1754                 return __bpf_redirect_no_mac(skb, dev, flags);
1755 }
1756 
1757 BPF_CALL_3(bpf_clone_redirect, struct sk_buff *, skb, u32, ifindex, u64, flags)
1758 {
1759         struct net_device *dev;
1760         struct sk_buff *clone;
1761         int ret;
1762 
1763         if (unlikely(flags & ~(BPF_F_INGRESS)))
1764                 return -EINVAL;
1765 
1766         dev = dev_get_by_index_rcu(dev_net(skb->dev), ifindex);
1767         if (unlikely(!dev))
1768                 return -EINVAL;
1769 
1770         clone = skb_clone(skb, GFP_ATOMIC);
1771         if (unlikely(!clone))
1772                 return -ENOMEM;
1773 
1774         /* For direct write, we need to keep the invariant that the skbs
1775          * we're dealing with need to be uncloned. Should uncloning fail
1776          * here, we need to free the just generated clone to unclone once
1777          * again.
1778          */
1779         ret = bpf_try_make_head_writable(skb);
1780         if (unlikely(ret)) {
1781                 kfree_skb(clone);
1782                 return -ENOMEM;
1783         }
1784 
1785         return __bpf_redirect(clone, dev, flags);
1786 }
1787 
1788 static const struct bpf_func_proto bpf_clone_redirect_proto = {
1789         .func           = bpf_clone_redirect,
1790         .gpl_only       = false,
1791         .ret_type       = RET_INTEGER,
1792         .arg1_type      = ARG_PTR_TO_CTX,
1793         .arg2_type      = ARG_ANYTHING,
1794         .arg3_type      = ARG_ANYTHING,
1795 };
1796 
1797 struct redirect_info {
1798         u32 ifindex;
1799         u32 flags;
1800         struct bpf_map *map;
1801         struct bpf_map *map_to_flush;
1802         unsigned long   map_owner;
1803 };
1804 
1805 static DEFINE_PER_CPU(struct redirect_info, redirect_info);
1806 
1807 BPF_CALL_2(bpf_redirect, u32, ifindex, u64, flags)
1808 {
1809         struct redirect_info *ri = this_cpu_ptr(&redirect_info);
1810 
1811         if (unlikely(flags & ~(BPF_F_INGRESS)))
1812                 return TC_ACT_SHOT;
1813 
1814         ri->ifindex = ifindex;
1815         ri->flags = flags;
1816 
1817         return TC_ACT_REDIRECT;
1818 }
1819 
1820 int skb_do_redirect(struct sk_buff *skb)
1821 {
1822         struct redirect_info *ri = this_cpu_ptr(&redirect_info);
1823         struct net_device *dev;
1824 
1825         dev = dev_get_by_index_rcu(dev_net(skb->dev), ri->ifindex);
1826         ri->ifindex = 0;
1827         if (unlikely(!dev)) {
1828                 kfree_skb(skb);
1829                 return -EINVAL;
1830         }
1831 
1832         return __bpf_redirect(skb, dev, ri->flags);
1833 }
1834 
1835 static const struct bpf_func_proto bpf_redirect_proto = {
1836         .func           = bpf_redirect,
1837         .gpl_only       = false,
1838         .ret_type       = RET_INTEGER,
1839         .arg1_type      = ARG_ANYTHING,
1840         .arg2_type      = ARG_ANYTHING,
1841 };
1842 
1843 BPF_CALL_4(bpf_sk_redirect_map, struct sk_buff *, skb,
1844            struct bpf_map *, map, u32, key, u64, flags)
1845 {
1846         struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
1847 
1848         /* If user passes invalid input drop the packet. */
1849         if (unlikely(flags))
1850                 return SK_DROP;
1851 
1852         tcb->bpf.key = key;
1853         tcb->bpf.flags = flags;
1854         tcb->bpf.map = map;
1855 
1856         return SK_PASS;
1857 }
1858 
1859 struct sock *do_sk_redirect_map(struct sk_buff *skb)
1860 {
1861         struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
1862         struct sock *sk = NULL;
1863 
1864         if (tcb->bpf.map) {
1865                 sk = __sock_map_lookup_elem(tcb->bpf.map, tcb->bpf.key);
1866 
1867                 tcb->bpf.key = 0;
1868                 tcb->bpf.map = NULL;
1869         }
1870 
1871         return sk;
1872 }
1873 
1874 static const struct bpf_func_proto bpf_sk_redirect_map_proto = {
1875         .func           = bpf_sk_redirect_map,
1876         .gpl_only       = false,
1877         .ret_type       = RET_INTEGER,
1878         .arg1_type      = ARG_PTR_TO_CTX,
1879         .arg2_type      = ARG_CONST_MAP_PTR,
1880         .arg3_type      = ARG_ANYTHING,
1881         .arg4_type      = ARG_ANYTHING,
1882 };
1883 
1884 BPF_CALL_1(bpf_get_cgroup_classid, const struct sk_buff *, skb)
1885 {
1886         return task_get_classid(skb);
1887 }
1888 
1889 static const struct bpf_func_proto bpf_get_cgroup_classid_proto = {
1890         .func           = bpf_get_cgroup_classid,
1891         .gpl_only       = false,
1892         .ret_type       = RET_INTEGER,
1893         .arg1_type      = ARG_PTR_TO_CTX,
1894 };
1895 
1896 BPF_CALL_1(bpf_get_route_realm, const struct sk_buff *, skb)
1897 {
1898         return dst_tclassid(skb);
1899 }
1900 
1901 static const struct bpf_func_proto bpf_get_route_realm_proto = {
1902         .func           = bpf_get_route_realm,
1903         .gpl_only       = false,
1904         .ret_type       = RET_INTEGER,
1905         .arg1_type      = ARG_PTR_TO_CTX,
1906 };
1907 
1908 BPF_CALL_1(bpf_get_hash_recalc, struct sk_buff *, skb)
1909 {
1910         /* If skb_clear_hash() was called due to mangling, we can
1911          * trigger SW recalculation here. Later access to hash
1912          * can then use the inline skb->hash via context directly
1913          * instead of calling this helper again.
1914          */
1915         return skb_get_hash(skb);
1916 }
1917 
1918 static const struct bpf_func_proto bpf_get_hash_recalc_proto = {
1919         .func           = bpf_get_hash_recalc,
1920         .gpl_only       = false,
1921         .ret_type       = RET_INTEGER,
1922         .arg1_type      = ARG_PTR_TO_CTX,
1923 };
1924 
1925 BPF_CALL_1(bpf_set_hash_invalid, struct sk_buff *, skb)
1926 {
1927         /* After all direct packet write, this can be used once for
1928          * triggering a lazy recalc on next skb_get_hash() invocation.
1929          */
1930         skb_clear_hash(skb);
1931         return 0;
1932 }
1933 
1934 static const struct bpf_func_proto bpf_set_hash_invalid_proto = {
1935         .func           = bpf_set_hash_invalid,
1936         .gpl_only       = false,
1937         .ret_type       = RET_INTEGER,
1938         .arg1_type      = ARG_PTR_TO_CTX,
1939 };
1940 
1941 BPF_CALL_2(bpf_set_hash, struct sk_buff *, skb, u32, hash)
1942 {
1943         /* Set user specified hash as L4(+), so that it gets returned
1944          * on skb_get_hash() call unless BPF prog later on triggers a
1945          * skb_clear_hash().
1946          */
1947         __skb_set_sw_hash(skb, hash, true);
1948         return 0;
1949 }
1950 
1951 static const struct bpf_func_proto bpf_set_hash_proto = {
1952         .func           = bpf_set_hash,
1953         .gpl_only       = false,
1954         .ret_type       = RET_INTEGER,
1955         .arg1_type      = ARG_PTR_TO_CTX,
1956         .arg2_type      = ARG_ANYTHING,
1957 };
1958 
1959 BPF_CALL_3(bpf_skb_vlan_push, struct sk_buff *, skb, __be16, vlan_proto,
1960            u16, vlan_tci)
1961 {
1962         int ret;
1963 
1964         if (unlikely(vlan_proto != htons(ETH_P_8021Q) &&
1965                      vlan_proto != htons(ETH_P_8021AD)))
1966                 vlan_proto = htons(ETH_P_8021Q);
1967 
1968         bpf_push_mac_rcsum(skb);
1969         ret = skb_vlan_push(skb, vlan_proto, vlan_tci);
1970         bpf_pull_mac_rcsum(skb);
1971 
1972         bpf_compute_data_pointers(skb);
1973         return ret;
1974 }
1975 
1976 const struct bpf_func_proto bpf_skb_vlan_push_proto = {
1977         .func           = bpf_skb_vlan_push,
1978         .gpl_only       = false,
1979         .ret_type       = RET_INTEGER,
1980         .arg1_type      = ARG_PTR_TO_CTX,
1981         .arg2_type      = ARG_ANYTHING,
1982         .arg3_type      = ARG_ANYTHING,
1983 };
1984 EXPORT_SYMBOL_GPL(bpf_skb_vlan_push_proto);
1985 
1986 BPF_CALL_1(bpf_skb_vlan_pop, struct sk_buff *, skb)
1987 {
1988         int ret;
1989 
1990         bpf_push_mac_rcsum(skb);
1991         ret = skb_vlan_pop(skb);
1992         bpf_pull_mac_rcsum(skb);
1993 
1994         bpf_compute_data_pointers(skb);
1995         return ret;
1996 }
1997 
1998 const struct bpf_func_proto bpf_skb_vlan_pop_proto = {
1999         .func           = bpf_skb_vlan_pop,
2000         .gpl_only       = false,
2001         .ret_type       = RET_INTEGER,
2002         .arg1_type      = ARG_PTR_TO_CTX,
2003 };
2004 EXPORT_SYMBOL_GPL(bpf_skb_vlan_pop_proto);
2005 
2006 static int bpf_skb_generic_push(struct sk_buff *skb, u32 off, u32 len)
2007 {
2008         /* Caller already did skb_cow() with len as headroom,
2009          * so no need to do it here.
2010          */
2011         skb_push(skb, len);
2012         memmove(skb->data, skb->data + len, off);
2013         memset(skb->data + off, 0, len);
2014 
2015         /* No skb_postpush_rcsum(skb, skb->data + off, len)
2016          * needed here as it does not change the skb->csum
2017          * result for checksum complete when summing over
2018          * zeroed blocks.
2019          */
2020         return 0;
2021 }
2022 
2023 static int bpf_skb_generic_pop(struct sk_buff *skb, u32 off, u32 len)
2024 {
2025         /* skb_ensure_writable() is not needed here, as we're
2026          * already working on an uncloned skb.
2027          */
2028         if (unlikely(!pskb_may_pull(skb, off + len)))
2029                 return -ENOMEM;
2030 
2031         skb_postpull_rcsum(skb, skb->data + off, len);
2032         memmove(skb->data + len, skb->data, off);
2033         __skb_pull(skb, len);
2034 
2035         return 0;
2036 }
2037 
2038 static int bpf_skb_net_hdr_push(struct sk_buff *skb, u32 off, u32 len)
2039 {
2040         bool trans_same = skb->transport_header == skb->network_header;
2041         int ret;
2042 
2043         /* There's no need for __skb_push()/__skb_pull() pair to
2044          * get to the start of the mac header as we're guaranteed
2045          * to always start from here under eBPF.
2046          */
2047         ret = bpf_skb_generic_push(skb, off, len);
2048         if (likely(!ret)) {
2049                 skb->mac_header -= len;
2050                 skb->network_header -= len;
2051                 if (trans_same)
2052                         skb->transport_header = skb->network_header;
2053         }
2054 
2055         return ret;
2056 }
2057 
2058 static int bpf_skb_net_hdr_pop(struct sk_buff *skb, u32 off, u32 len)
2059 {
2060         bool trans_same = skb->transport_header == skb->network_header;
2061         int ret;
2062 
2063         /* Same here, __skb_push()/__skb_pull() pair not needed. */
2064         ret = bpf_skb_generic_pop(skb, off, len);
2065         if (likely(!ret)) {
2066                 skb->mac_header += len;
2067                 skb->network_header += len;
2068                 if (trans_same)
2069                         skb->transport_header = skb->network_header;
2070         }
2071 
2072         return ret;
2073 }
2074 
2075 static int bpf_skb_proto_4_to_6(struct sk_buff *skb)
2076 {
2077         const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
2078         u32 off = skb_mac_header_len(skb);
2079         int ret;
2080 
2081         ret = skb_cow(skb, len_diff);
2082         if (unlikely(ret < 0))
2083                 return ret;
2084 
2085         ret = bpf_skb_net_hdr_push(skb, off, len_diff);
2086         if (unlikely(ret < 0))
2087                 return ret;
2088 
2089         if (skb_is_gso(skb)) {
2090                 /* SKB_GSO_TCPV4 needs to be changed into
2091                  * SKB_GSO_TCPV6.
2092                  */
2093                 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) {
2094                         skb_shinfo(skb)->gso_type &= ~SKB_GSO_TCPV4;
2095                         skb_shinfo(skb)->gso_type |=  SKB_GSO_TCPV6;
2096                 }
2097 
2098                 /* Due to IPv6 header, MSS needs to be downgraded. */
2099                 skb_shinfo(skb)->gso_size -= len_diff;
2100                 /* Header must be checked, and gso_segs recomputed. */
2101                 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2102                 skb_shinfo(skb)->gso_segs = 0;
2103         }
2104 
2105         skb->protocol = htons(ETH_P_IPV6);
2106         skb_clear_hash(skb);
2107 
2108         return 0;
2109 }
2110 
2111 static int bpf_skb_proto_6_to_4(struct sk_buff *skb)
2112 {
2113         const u32 len_diff = sizeof(struct ipv6hdr) - sizeof(struct iphdr);
2114         u32 off = skb_mac_header_len(skb);
2115         int ret;
2116 
2117         ret = skb_unclone(skb, GFP_ATOMIC);
2118         if (unlikely(ret < 0))
2119                 return ret;
2120 
2121         ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
2122         if (unlikely(ret < 0))
2123                 return ret;
2124 
2125         if (skb_is_gso(skb)) {
2126                 /* SKB_GSO_TCPV6 needs to be changed into
2127                  * SKB_GSO_TCPV4.
2128                  */
2129                 if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6) {
2130                         skb_shinfo(skb)->gso_type &= ~SKB_GSO_TCPV6;
2131                         skb_shinfo(skb)->gso_type |=  SKB_GSO_TCPV4;
2132                 }
2133 
2134                 /* Due to IPv4 header, MSS can be upgraded. */
2135                 skb_shinfo(skb)->gso_size += len_diff;
2136                 /* Header must be checked, and gso_segs recomputed. */
2137                 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2138                 skb_shinfo(skb)->gso_segs = 0;
2139         }
2140 
2141         skb->protocol = htons(ETH_P_IP);
2142         skb_clear_hash(skb);
2143 
2144         return 0;
2145 }
2146 
2147 static int bpf_skb_proto_xlat(struct sk_buff *skb, __be16 to_proto)
2148 {
2149         __be16 from_proto = skb->protocol;
2150 
2151         if (from_proto == htons(ETH_P_IP) &&
2152               to_proto == htons(ETH_P_IPV6))
2153                 return bpf_skb_proto_4_to_6(skb);
2154 
2155         if (from_proto == htons(ETH_P_IPV6) &&
2156               to_proto == htons(ETH_P_IP))
2157                 return bpf_skb_proto_6_to_4(skb);
2158 
2159         return -ENOTSUPP;
2160 }
2161 
2162 BPF_CALL_3(bpf_skb_change_proto, struct sk_buff *, skb, __be16, proto,
2163            u64, flags)
2164 {
2165         int ret;
2166 
2167         if (unlikely(flags))
2168                 return -EINVAL;
2169 
2170         /* General idea is that this helper does the basic groundwork
2171          * needed for changing the protocol, and eBPF program fills the
2172          * rest through bpf_skb_store_bytes(), bpf_lX_csum_replace()
2173          * and other helpers, rather than passing a raw buffer here.
2174          *
2175          * The rationale is to keep this minimal and without a need to
2176          * deal with raw packet data. F.e. even if we would pass buffers
2177          * here, the program still needs to call the bpf_lX_csum_replace()
2178          * helpers anyway. Plus, this way we keep also separation of
2179          * concerns, since f.e. bpf_skb_store_bytes() should only take
2180          * care of stores.
2181          *
2182          * Currently, additional options and extension header space are
2183          * not supported, but flags register is reserved so we can adapt
2184          * that. For offloads, we mark packet as dodgy, so that headers
2185          * need to be verified first.
2186          */
2187         ret = bpf_skb_proto_xlat(skb, proto);
2188         bpf_compute_data_pointers(skb);
2189         return ret;
2190 }
2191 
2192 static const struct bpf_func_proto bpf_skb_change_proto_proto = {
2193         .func           = bpf_skb_change_proto,
2194         .gpl_only       = false,
2195         .ret_type       = RET_INTEGER,
2196         .arg1_type      = ARG_PTR_TO_CTX,
2197         .arg2_type      = ARG_ANYTHING,
2198         .arg3_type      = ARG_ANYTHING,
2199 };
2200 
2201 BPF_CALL_2(bpf_skb_change_type, struct sk_buff *, skb, u32, pkt_type)
2202 {
2203         /* We only allow a restricted subset to be changed for now. */
2204         if (unlikely(!skb_pkt_type_ok(skb->pkt_type) ||
2205                      !skb_pkt_type_ok(pkt_type)))
2206                 return -EINVAL;
2207 
2208         skb->pkt_type = pkt_type;
2209         return 0;
2210 }
2211 
2212 static const struct bpf_func_proto bpf_skb_change_type_proto = {
2213         .func           = bpf_skb_change_type,
2214         .gpl_only       = false,
2215         .ret_type       = RET_INTEGER,
2216         .arg1_type      = ARG_PTR_TO_CTX,
2217         .arg2_type      = ARG_ANYTHING,
2218 };
2219 
2220 static u32 bpf_skb_net_base_len(const struct sk_buff *skb)
2221 {
2222         switch (skb->protocol) {
2223         case htons(ETH_P_IP):
2224                 return sizeof(struct iphdr);
2225         case htons(ETH_P_IPV6):
2226                 return sizeof(struct ipv6hdr);
2227         default:
2228                 return ~0U;
2229         }
2230 }
2231 
2232 static int bpf_skb_net_grow(struct sk_buff *skb, u32 len_diff)
2233 {
2234         u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb);
2235         int ret;
2236 
2237         ret = skb_cow(skb, len_diff);
2238         if (unlikely(ret < 0))
2239                 return ret;
2240 
2241         ret = bpf_skb_net_hdr_push(skb, off, len_diff);
2242         if (unlikely(ret < 0))
2243                 return ret;
2244 
2245         if (skb_is_gso(skb)) {
2246                 /* Due to header grow, MSS needs to be downgraded. */
2247                 skb_shinfo(skb)->gso_size -= len_diff;
2248                 /* Header must be checked, and gso_segs recomputed. */
2249                 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2250                 skb_shinfo(skb)->gso_segs = 0;
2251         }
2252 
2253         return 0;
2254 }
2255 
2256 static int bpf_skb_net_shrink(struct sk_buff *skb, u32 len_diff)
2257 {
2258         u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb);
2259         int ret;
2260 
2261         ret = skb_unclone(skb, GFP_ATOMIC);
2262         if (unlikely(ret < 0))
2263                 return ret;
2264 
2265         ret = bpf_skb_net_hdr_pop(skb, off, len_diff);
2266         if (unlikely(ret < 0))
2267                 return ret;
2268 
2269         if (skb_is_gso(skb)) {
2270                 /* Due to header shrink, MSS can be upgraded. */
2271                 skb_shinfo(skb)->gso_size += len_diff;
2272                 /* Header must be checked, and gso_segs recomputed. */
2273                 skb_shinfo(skb)->gso_type |= SKB_GSO_DODGY;
2274                 skb_shinfo(skb)->gso_segs = 0;
2275         }
2276 
2277         return 0;
2278 }
2279 
2280 static u32 __bpf_skb_max_len(const struct sk_buff *skb)
2281 {
2282         return skb->dev->mtu + skb->dev->hard_header_len;
2283 }
2284 
2285 static int bpf_skb_adjust_net(struct sk_buff *skb, s32 len_diff)
2286 {
2287         bool trans_same = skb->transport_header == skb->network_header;
2288         u32 len_cur, len_diff_abs = abs(len_diff);
2289         u32 len_min = bpf_skb_net_base_len(skb);
2290         u32 len_max = __bpf_skb_max_len(skb);
2291         __be16 proto = skb->protocol;
2292         bool shrink = len_diff < 0;
2293         int ret;
2294 
2295         if (unlikely(len_diff_abs > 0xfffU))
2296                 return -EFAULT;
2297         if (unlikely(proto != htons(ETH_P_IP) &&
2298                      proto != htons(ETH_P_IPV6)))
2299                 return -ENOTSUPP;
2300 
2301         len_cur = skb->len - skb_network_offset(skb);
2302         if (skb_transport_header_was_set(skb) && !trans_same)
2303                 len_cur = skb_network_header_len(skb);
2304         if ((shrink && (len_diff_abs >= len_cur ||
2305                         len_cur - len_diff_abs < len_min)) ||
2306             (!shrink && (skb->len + len_diff_abs > len_max &&
2307                          !skb_is_gso(skb))))
2308                 return -ENOTSUPP;
2309 
2310         ret = shrink ? bpf_skb_net_shrink(skb, len_diff_abs) :
2311                        bpf_skb_net_grow(skb, len_diff_abs);
2312 
2313         bpf_compute_data_pointers(skb);
2314         return ret;
2315 }
2316 
2317 BPF_CALL_4(bpf_skb_adjust_room, struct sk_buff *, skb, s32, len_diff,
2318            u32, mode, u64, flags)
2319 {
2320         if (unlikely(flags))
2321                 return -EINVAL;
2322         if (likely(mode == BPF_ADJ_ROOM_NET))
2323                 return bpf_skb_adjust_net(skb, len_diff);
2324 
2325         return -ENOTSUPP;
2326 }
2327 
2328 static const struct bpf_func_proto bpf_skb_adjust_room_proto = {
2329         .func           = bpf_skb_adjust_room,
2330         .gpl_only       = false,
2331         .ret_type       = RET_INTEGER,
2332         .arg1_type      = ARG_PTR_TO_CTX,
2333         .arg2_type      = ARG_ANYTHING,
2334         .arg3_type      = ARG_ANYTHING,
2335         .arg4_type      = ARG_ANYTHING,
2336 };
2337 
2338 static u32 __bpf_skb_min_len(const struct sk_buff *skb)
2339 {
2340         u32 min_len = skb_network_offset(skb);
2341 
2342         if (skb_transport_header_was_set(skb))
2343                 min_len = skb_transport_offset(skb);
2344         if (skb->ip_summed == CHECKSUM_PARTIAL)
2345                 min_len = skb_checksum_start_offset(skb) +
2346                           skb->csum_offset + sizeof(__sum16);
2347         return min_len;
2348 }
2349 
2350 static int bpf_skb_grow_rcsum(struct sk_buff *skb, unsigned int new_len)
2351 {
2352         unsigned int old_len = skb->len;
2353         int ret;
2354 
2355         ret = __skb_grow_rcsum(skb, new_len);
2356         if (!ret)
2357                 memset(skb->data + old_len, 0, new_len - old_len);
2358         return ret;
2359 }
2360 
2361 static int bpf_skb_trim_rcsum(struct sk_buff *skb, unsigned int new_len)
2362 {
2363         return __skb_trim_rcsum(skb, new_len);
2364 }
2365 
2366 BPF_CALL_3(bpf_skb_change_tail, struct sk_buff *, skb, u32, new_len,
2367            u64, flags)
2368 {
2369         u32 max_len = __bpf_skb_max_len(skb);
2370         u32 min_len = __bpf_skb_min_len(skb);
2371         int ret;
2372 
2373         if (unlikely(flags || new_len > max_len || new_len < min_len))
2374                 return -EINVAL;
2375         if (skb->encapsulation)
2376                 return -ENOTSUPP;
2377 
2378         /* The basic idea of this helper is that it's performing the
2379          * needed work to either grow or trim an skb, and eBPF program
2380          * rewrites the rest via helpers like bpf_skb_store_bytes(),
2381          * bpf_lX_csum_replace() and others rather than passing a raw
2382          * buffer here. This one is a slow path helper and intended
2383          * for replies with control messages.
2384          *
2385          * Like in bpf_skb_change_proto(), we want to keep this rather
2386          * minimal and without protocol specifics so that we are able
2387          * to separate concerns as in bpf_skb_store_bytes() should only
2388          * be the one responsible for writing buffers.
2389          *
2390          * It's really expected to be a slow path operation here for
2391          * control message replies, so we're implicitly linearizing,
2392          * uncloning and drop offloads from the skb by this.
2393          */
2394         ret = __bpf_try_make_writable(skb, skb->len);
2395         if (!ret) {
2396                 if (new_len > skb->len)
2397                         ret = bpf_skb_grow_rcsum(skb, new_len);
2398                 else if (new_len < skb->len)
2399                         ret = bpf_skb_trim_rcsum(skb, new_len);
2400                 if (!ret && skb_is_gso(skb))
2401                         skb_gso_reset(skb);
2402         }
2403 
2404         bpf_compute_data_pointers(skb);
2405         return ret;
2406 }
2407 
2408 static const struct bpf_func_proto bpf_skb_change_tail_proto = {
2409         .func           = bpf_skb_change_tail,
2410         .gpl_only       = false,
2411         .ret_type       = RET_INTEGER,
2412         .arg1_type      = ARG_PTR_TO_CTX,
2413         .arg2_type      = ARG_ANYTHING,
2414         .arg3_type      = ARG_ANYTHING,
2415 };
2416 
2417 BPF_CALL_3(bpf_skb_change_head, struct sk_buff *, skb, u32, head_room,
2418            u64, flags)
2419 {
2420         u32 max_len = __bpf_skb_max_len(skb);
2421         u32 new_len = skb->len + head_room;
2422         int ret;
2423 
2424         if (unlikely(flags || (!skb_is_gso(skb) && new_len > max_len) ||
2425                      new_len < skb->len))
2426                 return -EINVAL;
2427 
2428         ret = skb_cow(skb, head_room);
2429         if (likely(!ret)) {
2430                 /* Idea for this helper is that we currently only
2431                  * allow to expand on mac header. This means that
2432                  * skb->protocol network header, etc, stay as is.
2433                  * Compared to bpf_skb_change_tail(), we're more
2434                  * flexible due to not needing to linearize or
2435                  * reset GSO. Intention for this helper is to be
2436                  * used by an L3 skb that needs to push mac header
2437                  * for redirection into L2 device.
2438                  */
2439                 __skb_push(skb, head_room);
2440                 memset(skb->data, 0, head_room);
2441                 skb_reset_mac_header(skb);
2442         }
2443 
2444         bpf_compute_data_pointers(skb);
2445         return 0;
2446 }
2447 
2448 static const struct bpf_func_proto bpf_skb_change_head_proto = {
2449         .func           = bpf_skb_change_head,
2450         .gpl_only       = false,
2451         .ret_type       = RET_INTEGER,
2452         .arg1_type      = ARG_PTR_TO_CTX,
2453         .arg2_type      = ARG_ANYTHING,
2454         .arg3_type      = ARG_ANYTHING,
2455 };
2456 
2457 static unsigned long xdp_get_metalen(const struct xdp_buff *xdp)
2458 {
2459         return xdp_data_meta_unsupported(xdp) ? 0 :
2460                xdp->data - xdp->data_meta;
2461 }
2462 
2463 BPF_CALL_2(bpf_xdp_adjust_head, struct xdp_buff *, xdp, int, offset)
2464 {
2465         unsigned long metalen = xdp_get_metalen(xdp);
2466         void *data_start = xdp->data_hard_start + metalen;
2467         void *data = xdp->data + offset;
2468 
2469         if (unlikely(data < data_start ||
2470                      data > xdp->data_end - ETH_HLEN))
2471                 return -EINVAL;
2472 
2473         if (metalen)
2474                 memmove(xdp->data_meta + offset,
2475                         xdp->data_meta, metalen);
2476         xdp->data_meta += offset;
2477         xdp->data = data;
2478 
2479         return 0;
2480 }
2481 
2482 static const struct bpf_func_proto bpf_xdp_adjust_head_proto = {
2483         .func           = bpf_xdp_adjust_head,
2484         .gpl_only       = false,
2485         .ret_type       = RET_INTEGER,
2486         .arg1_type      = ARG_PTR_TO_CTX,
2487         .arg2_type      = ARG_ANYTHING,
2488 };
2489 
2490 BPF_CALL_2(bpf_xdp_adjust_meta, struct xdp_buff *, xdp, int, offset)
2491 {
2492         void *meta = xdp->data_meta + offset;
2493         unsigned long metalen = xdp->data - meta;
2494 
2495         if (xdp_data_meta_unsupported(xdp))
2496                 return -ENOTSUPP;
2497         if (unlikely(meta < xdp->data_hard_start ||
2498                      meta > xdp->data))
2499                 return -EINVAL;
2500         if (unlikely((metalen & (sizeof(__u32) - 1)) ||
2501                      (metalen > 32)))
2502                 return -EACCES;
2503 
2504         xdp->data_meta = meta;
2505 
2506         return 0;
2507 }
2508 
2509 static const struct bpf_func_proto bpf_xdp_adjust_meta_proto = {
2510         .func           = bpf_xdp_adjust_meta,
2511         .gpl_only       = false,
2512         .ret_type       = RET_INTEGER,
2513         .arg1_type      = ARG_PTR_TO_CTX,
2514         .arg2_type      = ARG_ANYTHING,
2515 };
2516 
2517 static int __bpf_tx_xdp(struct net_device *dev,
2518                         struct bpf_map *map,
2519                         struct xdp_buff *xdp,
2520                         u32 index)
2521 {
2522         int err;
2523 
2524         if (!dev->netdev_ops->ndo_xdp_xmit) {
2525                 return -EOPNOTSUPP;
2526         }
2527 
2528         err = dev->netdev_ops->ndo_xdp_xmit(dev, xdp);
2529         if (err)
2530                 return err;
2531         dev->netdev_ops->ndo_xdp_flush(dev);
2532         return 0;
2533 }
2534 
2535 static int __bpf_tx_xdp_map(struct net_device *dev_rx, void *fwd,
2536                             struct bpf_map *map,
2537                             struct xdp_buff *xdp,
2538                             u32 index)
2539 {
2540         int err;
2541 
2542         if (map->map_type == BPF_MAP_TYPE_DEVMAP) {
2543                 struct net_device *dev = fwd;
2544 
2545                 if (!dev->netdev_ops->ndo_xdp_xmit)
2546                         return -EOPNOTSUPP;
2547 
2548                 err = dev->netdev_ops->ndo_xdp_xmit(dev, xdp);
2549                 if (err)
2550                         return err;
2551                 __dev_map_insert_ctx(map, index);
2552 
2553         } else if (map->map_type == BPF_MAP_TYPE_CPUMAP) {
2554                 struct bpf_cpu_map_entry *rcpu = fwd;
2555 
2556                 err = cpu_map_enqueue(rcpu, xdp, dev_rx);
2557                 if (err)
2558                         return err;
2559                 __cpu_map_insert_ctx(map, index);
2560         }
2561         return 0;
2562 }
2563 
2564 void xdp_do_flush_map(void)
2565 {
2566         struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2567         struct bpf_map *map = ri->map_to_flush;
2568 
2569         ri->map_to_flush = NULL;
2570         if (map) {
2571                 switch (map->map_type) {
2572                 case BPF_MAP_TYPE_DEVMAP:
2573                         __dev_map_flush(map);
2574                         break;
2575                 case BPF_MAP_TYPE_CPUMAP:
2576                         __cpu_map_flush(map);
2577                         break;
2578                 default:
2579                         break;
2580                 }
2581         }
2582 }
2583 EXPORT_SYMBOL_GPL(xdp_do_flush_map);
2584 
2585 static void *__xdp_map_lookup_elem(struct bpf_map *map, u32 index)
2586 {
2587         switch (map->map_type) {
2588         case BPF_MAP_TYPE_DEVMAP:
2589                 return __dev_map_lookup_elem(map, index);
2590         case BPF_MAP_TYPE_CPUMAP:
2591                 return __cpu_map_lookup_elem(map, index);
2592         default:
2593                 return NULL;
2594         }
2595 }
2596 
2597 static inline bool xdp_map_invalid(const struct bpf_prog *xdp_prog,
2598                                    unsigned long aux)
2599 {
2600         return (unsigned long)xdp_prog->aux != aux;
2601 }
2602 
2603 static int xdp_do_redirect_map(struct net_device *dev, struct xdp_buff *xdp,
2604                                struct bpf_prog *xdp_prog)
2605 {
2606         struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2607         unsigned long map_owner = ri->map_owner;
2608         struct bpf_map *map = ri->map;
2609         u32 index = ri->ifindex;
2610         void *fwd = NULL;
2611         int err;
2612 
2613         ri->ifindex = 0;
2614         ri->map = NULL;
2615         ri->map_owner = 0;
2616 
2617         if (unlikely(xdp_map_invalid(xdp_prog, map_owner))) {
2618                 err = -EFAULT;
2619                 map = NULL;
2620                 goto err;
2621         }
2622 
2623         fwd = __xdp_map_lookup_elem(map, index);
2624         if (!fwd) {
2625                 err = -EINVAL;
2626                 goto err;
2627         }
2628         if (ri->map_to_flush && ri->map_to_flush != map)
2629                 xdp_do_flush_map();
2630 
2631         err = __bpf_tx_xdp_map(dev, fwd, map, xdp, index);
2632         if (unlikely(err))
2633                 goto err;
2634 
2635         ri->map_to_flush = map;
2636         _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index);
2637         return 0;
2638 err:
2639         _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err);
2640         return err;
2641 }
2642 
2643 int xdp_do_redirect(struct net_device *dev, struct xdp_buff *xdp,
2644                     struct bpf_prog *xdp_prog)
2645 {
2646         struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2647         struct net_device *fwd;
2648         u32 index = ri->ifindex;
2649         int err;
2650 
2651         if (ri->map)
2652                 return xdp_do_redirect_map(dev, xdp, xdp_prog);
2653 
2654         fwd = dev_get_by_index_rcu(dev_net(dev), index);
2655         ri->ifindex = 0;
2656         if (unlikely(!fwd)) {
2657                 err = -EINVAL;
2658                 goto err;
2659         }
2660 
2661         err = __bpf_tx_xdp(fwd, NULL, xdp, 0);
2662         if (unlikely(err))
2663                 goto err;
2664 
2665         _trace_xdp_redirect(dev, xdp_prog, index);
2666         return 0;
2667 err:
2668         _trace_xdp_redirect_err(dev, xdp_prog, index, err);
2669         return err;
2670 }
2671 EXPORT_SYMBOL_GPL(xdp_do_redirect);
2672 
2673 static int __xdp_generic_ok_fwd_dev(struct sk_buff *skb, struct net_device *fwd)
2674 {
2675         unsigned int len;
2676 
2677         if (unlikely(!(fwd->flags & IFF_UP)))
2678                 return -ENETDOWN;
2679 
2680         len = fwd->mtu + fwd->hard_header_len + VLAN_HLEN;
2681         if (skb->len > len)
2682                 return -EMSGSIZE;
2683 
2684         return 0;
2685 }
2686 
2687 int xdp_do_generic_redirect_map(struct net_device *dev, struct sk_buff *skb,
2688                                 struct bpf_prog *xdp_prog)
2689 {
2690         struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2691         unsigned long map_owner = ri->map_owner;
2692         struct bpf_map *map = ri->map;
2693         struct net_device *fwd = NULL;
2694         u32 index = ri->ifindex;
2695         int err = 0;
2696 
2697         ri->ifindex = 0;
2698         ri->map = NULL;
2699         ri->map_owner = 0;
2700 
2701         if (unlikely(xdp_map_invalid(xdp_prog, map_owner))) {
2702                 err = -EFAULT;
2703                 map = NULL;
2704                 goto err;
2705         }
2706         fwd = __xdp_map_lookup_elem(map, index);
2707         if (unlikely(!fwd)) {
2708                 err = -EINVAL;
2709                 goto err;
2710         }
2711 
2712         if (map->map_type == BPF_MAP_TYPE_DEVMAP) {
2713                 if (unlikely((err = __xdp_generic_ok_fwd_dev(skb, fwd))))
2714                         goto err;
2715                 skb->dev = fwd;
2716         } else {
2717                 /* TODO: Handle BPF_MAP_TYPE_CPUMAP */
2718                 err = -EBADRQC;
2719                 goto err;
2720         }
2721 
2722         _trace_xdp_redirect_map(dev, xdp_prog, fwd, map, index);
2723         return 0;
2724 err:
2725         _trace_xdp_redirect_map_err(dev, xdp_prog, fwd, map, index, err);
2726         return err;
2727 }
2728 
2729 int xdp_do_generic_redirect(struct net_device *dev, struct sk_buff *skb,
2730                             struct bpf_prog *xdp_prog)
2731 {
2732         struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2733         u32 index = ri->ifindex;
2734         struct net_device *fwd;
2735         int err = 0;
2736 
2737         if (ri->map)
2738                 return xdp_do_generic_redirect_map(dev, skb, xdp_prog);
2739 
2740         ri->ifindex = 0;
2741         fwd = dev_get_by_index_rcu(dev_net(dev), index);
2742         if (unlikely(!fwd)) {
2743                 err = -EINVAL;
2744                 goto err;
2745         }
2746 
2747         if (unlikely((err = __xdp_generic_ok_fwd_dev(skb, fwd))))
2748                 goto err;
2749 
2750         skb->dev = fwd;
2751         _trace_xdp_redirect(dev, xdp_prog, index);
2752         return 0;
2753 err:
2754         _trace_xdp_redirect_err(dev, xdp_prog, index, err);
2755         return err;
2756 }
2757 EXPORT_SYMBOL_GPL(xdp_do_generic_redirect);
2758 
2759 BPF_CALL_2(bpf_xdp_redirect, u32, ifindex, u64, flags)
2760 {
2761         struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2762 
2763         if (unlikely(flags))
2764                 return XDP_ABORTED;
2765 
2766         ri->ifindex = ifindex;
2767         ri->flags = flags;
2768         ri->map = NULL;
2769         ri->map_owner = 0;
2770 
2771         return XDP_REDIRECT;
2772 }
2773 
2774 static const struct bpf_func_proto bpf_xdp_redirect_proto = {
2775         .func           = bpf_xdp_redirect,
2776         .gpl_only       = false,
2777         .ret_type       = RET_INTEGER,
2778         .arg1_type      = ARG_ANYTHING,
2779         .arg2_type      = ARG_ANYTHING,
2780 };
2781 
2782 BPF_CALL_4(bpf_xdp_redirect_map, struct bpf_map *, map, u32, ifindex, u64, flags,
2783            unsigned long, map_owner)
2784 {
2785         struct redirect_info *ri = this_cpu_ptr(&redirect_info);
2786 
2787         if (unlikely(flags))
2788                 return XDP_ABORTED;
2789 
2790         ri->ifindex = ifindex;
2791         ri->flags = flags;
2792         ri->map = map;
2793         ri->map_owner = map_owner;
2794 
2795         return XDP_REDIRECT;
2796 }
2797 
2798 /* Note, arg4 is hidden from users and populated by the verifier
2799  * with the right pointer.
2800  */
2801 static const struct bpf_func_proto bpf_xdp_redirect_map_proto = {
2802         .func           = bpf_xdp_redirect_map,
2803         .gpl_only       = false,
2804         .ret_type       = RET_INTEGER,
2805         .arg1_type      = ARG_CONST_MAP_PTR,
2806         .arg2_type      = ARG_ANYTHING,
2807         .arg3_type      = ARG_ANYTHING,
2808 };
2809 
2810 bool bpf_helper_changes_pkt_data(void *func)
2811 {
2812         if (func == bpf_skb_vlan_push ||
2813             func == bpf_skb_vlan_pop ||
2814             func == bpf_skb_store_bytes ||
2815             func == bpf_skb_change_proto ||
2816             func == bpf_skb_change_head ||
2817             func == bpf_skb_change_tail ||
2818             func == bpf_skb_adjust_room ||
2819             func == bpf_skb_pull_data ||
2820             func == bpf_clone_redirect ||
2821             func == bpf_l3_csum_replace ||
2822             func == bpf_l4_csum_replace ||
2823             func == bpf_xdp_adjust_head ||
2824             func == bpf_xdp_adjust_meta)
2825                 return true;
2826 
2827         return false;
2828 }
2829 
2830 static unsigned long bpf_skb_copy(void *dst_buff, const void *skb,
2831                                   unsigned long off, unsigned long len)
2832 {
2833         void *ptr = skb_header_pointer(skb, off, len, dst_buff);
2834 
2835         if (unlikely(!ptr))
2836                 return len;
2837         if (ptr != dst_buff)
2838                 memcpy(dst_buff, ptr, len);
2839 
2840         return 0;
2841 }
2842 
2843 BPF_CALL_5(bpf_skb_event_output, struct sk_buff *, skb, struct bpf_map *, map,
2844            u64, flags, void *, meta, u64, meta_size)
2845 {
2846         u64 skb_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
2847 
2848         if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
2849                 return -EINVAL;
2850         if (unlikely(skb_size > skb->len))
2851                 return -EFAULT;
2852 
2853         return bpf_event_output(map, flags, meta, meta_size, skb, skb_size,
2854                                 bpf_skb_copy);
2855 }
2856 
2857 static const struct bpf_func_proto bpf_skb_event_output_proto = {
2858         .func           = bpf_skb_event_output,
2859         .gpl_only       = true,
2860         .ret_type       = RET_INTEGER,
2861         .arg1_type      = ARG_PTR_TO_CTX,
2862         .arg2_type      = ARG_CONST_MAP_PTR,
2863         .arg3_type      = ARG_ANYTHING,
2864         .arg4_type      = ARG_PTR_TO_MEM,
2865         .arg5_type      = ARG_CONST_SIZE,
2866 };
2867 
2868 static unsigned short bpf_tunnel_key_af(u64 flags)
2869 {
2870         return flags & BPF_F_TUNINFO_IPV6 ? AF_INET6 : AF_INET;
2871 }
2872 
2873 BPF_CALL_4(bpf_skb_get_tunnel_key, struct sk_buff *, skb, struct bpf_tunnel_key *, to,
2874            u32, size, u64, flags)
2875 {
2876         const struct ip_tunnel_info *info = skb_tunnel_info(skb);
2877         u8 compat[sizeof(struct bpf_tunnel_key)];
2878         void *to_orig = to;
2879         int err;
2880 
2881         if (unlikely(!info || (flags & ~(BPF_F_TUNINFO_IPV6)))) {
2882                 err = -EINVAL;
2883                 goto err_clear;
2884         }
2885         if (ip_tunnel_info_af(info) != bpf_tunnel_key_af(flags)) {
2886                 err = -EPROTO;
2887                 goto err_clear;
2888         }
2889         if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
2890                 err = -EINVAL;
2891                 switch (size) {
2892                 case offsetof(struct bpf_tunnel_key, tunnel_label):
2893                 case offsetof(struct bpf_tunnel_key, tunnel_ext):
2894                         goto set_compat;
2895                 case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
2896                         /* Fixup deprecated structure layouts here, so we have
2897                          * a common path later on.
2898                          */
2899                         if (ip_tunnel_info_af(info) != AF_INET)
2900                                 goto err_clear;
2901 set_compat:
2902                         to = (struct bpf_tunnel_key *)compat;
2903                         break;
2904                 default:
2905                         goto err_clear;
2906                 }
2907         }
2908 
2909         to->tunnel_id = be64_to_cpu(info->key.tun_id);
2910         to->tunnel_tos = info->key.tos;
2911         to->tunnel_ttl = info->key.ttl;
2912 
2913         if (flags & BPF_F_TUNINFO_IPV6) {
2914                 memcpy(to->remote_ipv6, &info->key.u.ipv6.src,
2915                        sizeof(to->remote_ipv6));
2916                 to->tunnel_label = be32_to_cpu(info->key.label);
2917         } else {
2918                 to->remote_ipv4 = be32_to_cpu(info->key.u.ipv4.src);
2919         }
2920 
2921         if (unlikely(size != sizeof(struct bpf_tunnel_key)))
2922                 memcpy(to_orig, to, size);
2923 
2924         return 0;
2925 err_clear:
2926         memset(to_orig, 0, size);
2927         return err;
2928 }
2929 
2930 static const struct bpf_func_proto bpf_skb_get_tunnel_key_proto = {
2931         .func           = bpf_skb_get_tunnel_key,
2932         .gpl_only       = false,
2933         .ret_type       = RET_INTEGER,
2934         .arg1_type      = ARG_PTR_TO_CTX,
2935         .arg2_type      = ARG_PTR_TO_UNINIT_MEM,
2936         .arg3_type      = ARG_CONST_SIZE,
2937         .arg4_type      = ARG_ANYTHING,
2938 };
2939 
2940 BPF_CALL_3(bpf_skb_get_tunnel_opt, struct sk_buff *, skb, u8 *, to, u32, size)
2941 {
2942         const struct ip_tunnel_info *info = skb_tunnel_info(skb);
2943         int err;
2944 
2945         if (unlikely(!info ||
2946                      !(info->key.tun_flags & TUNNEL_OPTIONS_PRESENT))) {
2947                 err = -ENOENT;
2948                 goto err_clear;
2949         }
2950         if (unlikely(size < info->options_len)) {
2951                 err = -ENOMEM;
2952                 goto err_clear;
2953         }
2954 
2955         ip_tunnel_info_opts_get(to, info);
2956         if (size > info->options_len)
2957                 memset(to + info->options_len, 0, size - info->options_len);
2958 
2959         return info->options_len;
2960 err_clear:
2961         memset(to, 0, size);
2962         return err;
2963 }
2964 
2965 static const struct bpf_func_proto bpf_skb_get_tunnel_opt_proto = {
2966         .func           = bpf_skb_get_tunnel_opt,
2967         .gpl_only       = false,
2968         .ret_type       = RET_INTEGER,
2969         .arg1_type      = ARG_PTR_TO_CTX,
2970         .arg2_type      = ARG_PTR_TO_UNINIT_MEM,
2971         .arg3_type      = ARG_CONST_SIZE,
2972 };
2973 
2974 static struct metadata_dst __percpu *md_dst;
2975 
2976 BPF_CALL_4(bpf_skb_set_tunnel_key, struct sk_buff *, skb,
2977            const struct bpf_tunnel_key *, from, u32, size, u64, flags)
2978 {
2979         struct metadata_dst *md = this_cpu_ptr(md_dst);
2980         u8 compat[sizeof(struct bpf_tunnel_key)];
2981         struct ip_tunnel_info *info;
2982 
2983         if (unlikely(flags & ~(BPF_F_TUNINFO_IPV6 | BPF_F_ZERO_CSUM_TX |
2984                                BPF_F_DONT_FRAGMENT)))
2985                 return -EINVAL;
2986         if (unlikely(size != sizeof(struct bpf_tunnel_key))) {
2987                 switch (size) {
2988                 case offsetof(struct bpf_tunnel_key, tunnel_label):
2989                 case offsetof(struct bpf_tunnel_key, tunnel_ext):
2990                 case offsetof(struct bpf_tunnel_key, remote_ipv6[1]):
2991                         /* Fixup deprecated structure layouts here, so we have
2992                          * a common path later on.
2993                          */
2994                         memcpy(compat, from, size);
2995                         memset(compat + size, 0, sizeof(compat) - size);
2996                         from = (const struct bpf_tunnel_key *) compat;
2997                         break;
2998                 default:
2999                         return -EINVAL;
3000                 }
3001         }
3002         if (unlikely((!(flags & BPF_F_TUNINFO_IPV6) && from->tunnel_label) ||
3003                      from->tunnel_ext))
3004                 return -EINVAL;
3005 
3006         skb_dst_drop(skb);
3007         dst_hold((struct dst_entry *) md);
3008         skb_dst_set(skb, (struct dst_entry *) md);
3009 
3010         info = &md->u.tun_info;
3011         info->mode = IP_TUNNEL_INFO_TX;
3012 
3013         info->key.tun_flags = TUNNEL_KEY | TUNNEL_CSUM | TUNNEL_NOCACHE;
3014         if (flags & BPF_F_DONT_FRAGMENT)
3015                 info->key.tun_flags |= TUNNEL_DONT_FRAGMENT;
3016 
3017         info->key.tun_id = cpu_to_be64(from->tunnel_id);
3018         info->key.tos = from->tunnel_tos;
3019         info->key.ttl = from->tunnel_ttl;
3020 
3021         if (flags & BPF_F_TUNINFO_IPV6) {
3022                 info->mode |= IP_TUNNEL_INFO_IPV6;
3023                 memcpy(&info->key.u.ipv6.dst, from->remote_ipv6,
3024                        sizeof(from->remote_ipv6));
3025                 info->key.label = cpu_to_be32(from->tunnel_label) &
3026                                   IPV6_FLOWLABEL_MASK;
3027         } else {
3028                 info->key.u.ipv4.dst = cpu_to_be32(from->remote_ipv4);
3029                 if (flags & BPF_F_ZERO_CSUM_TX)
3030                         info->key.tun_flags &= ~TUNNEL_CSUM;
3031         }
3032 
3033         return 0;
3034 }
3035 
3036 static const struct bpf_func_proto bpf_skb_set_tunnel_key_proto = {
3037         .func           = bpf_skb_set_tunnel_key,
3038         .gpl_only       = false,
3039         .ret_type       = RET_INTEGER,
3040         .arg1_type      = ARG_PTR_TO_CTX,
3041         .arg2_type      = ARG_PTR_TO_MEM,
3042         .arg3_type      = ARG_CONST_SIZE,
3043         .arg4_type      = ARG_ANYTHING,
3044 };
3045 
3046 BPF_CALL_3(bpf_skb_set_tunnel_opt, struct sk_buff *, skb,
3047            const u8 *, from, u32, size)
3048 {
3049         struct ip_tunnel_info *info = skb_tunnel_info(skb);
3050         const struct metadata_dst *md = this_cpu_ptr(md_dst);
3051 
3052         if (unlikely(info != &md->u.tun_info || (size & (sizeof(u32) - 1))))
3053                 return -EINVAL;
3054         if (unlikely(size > IP_TUNNEL_OPTS_MAX))
3055                 return -ENOMEM;
3056 
3057         ip_tunnel_info_opts_set(info, from, size);
3058 
3059         return 0;
3060 }
3061 
3062 static const struct bpf_func_proto bpf_skb_set_tunnel_opt_proto = {
3063         .func           = bpf_skb_set_tunnel_opt,
3064         .gpl_only       = false,
3065         .ret_type       = RET_INTEGER,
3066         .arg1_type      = ARG_PTR_TO_CTX,
3067         .arg2_type      = ARG_PTR_TO_MEM,
3068         .arg3_type      = ARG_CONST_SIZE,
3069 };
3070 
3071 static const struct bpf_func_proto *
3072 bpf_get_skb_set_tunnel_proto(enum bpf_func_id which)
3073 {
3074         if (!md_dst) {
3075                 struct metadata_dst __percpu *tmp;
3076 
3077                 tmp = metadata_dst_alloc_percpu(IP_TUNNEL_OPTS_MAX,
3078                                                 METADATA_IP_TUNNEL,
3079                                                 GFP_KERNEL);
3080                 if (!tmp)
3081                         return NULL;
3082                 if (cmpxchg(&md_dst, NULL, tmp))
3083                         metadata_dst_free_percpu(tmp);
3084         }
3085 
3086         switch (which) {
3087         case BPF_FUNC_skb_set_tunnel_key:
3088                 return &bpf_skb_set_tunnel_key_proto;
3089         case BPF_FUNC_skb_set_tunnel_opt:
3090                 return &bpf_skb_set_tunnel_opt_proto;
3091         default:
3092                 return NULL;
3093         }
3094 }
3095 
3096 BPF_CALL_3(bpf_skb_under_cgroup, struct sk_buff *, skb, struct bpf_map *, map,
3097            u32, idx)
3098 {
3099         struct bpf_array *array = container_of(map, struct bpf_array, map);
3100         struct cgroup *cgrp;
3101         struct sock *sk;
3102 
3103         sk = skb_to_full_sk(skb);
3104         if (!sk || !sk_fullsock(sk))
3105                 return -ENOENT;
3106         if (unlikely(idx >= array->map.max_entries))
3107                 return -E2BIG;
3108 
3109         cgrp = READ_ONCE(array->ptrs[idx]);
3110         if (unlikely(!cgrp))
3111                 return -EAGAIN;
3112 
3113         return sk_under_cgroup_hierarchy(sk, cgrp);
3114 }
3115 
3116 static const struct bpf_func_proto bpf_skb_under_cgroup_proto = {
3117         .func           = bpf_skb_under_cgroup,
3118         .gpl_only       = false,
3119         .ret_type       = RET_INTEGER,
3120         .arg1_type      = ARG_PTR_TO_CTX,
3121         .arg2_type      = ARG_CONST_MAP_PTR,
3122         .arg3_type      = ARG_ANYTHING,
3123 };
3124 
3125 static unsigned long bpf_xdp_copy(void *dst_buff, const void *src_buff,
3126                                   unsigned long off, unsigned long len)
3127 {
3128         memcpy(dst_buff, src_buff + off, len);
3129         return 0;
3130 }
3131 
3132 BPF_CALL_5(bpf_xdp_event_output, struct xdp_buff *, xdp, struct bpf_map *, map,
3133            u64, flags, void *, meta, u64, meta_size)
3134 {
3135         u64 xdp_size = (flags & BPF_F_CTXLEN_MASK) >> 32;
3136 
3137         if (unlikely(flags & ~(BPF_F_CTXLEN_MASK | BPF_F_INDEX_MASK)))
3138                 return -EINVAL;
3139         if (unlikely(xdp_size > (unsigned long)(xdp->data_end - xdp->data)))
3140                 return -EFAULT;
3141 
3142         return bpf_event_output(map, flags, meta, meta_size, xdp->data,
3143                                 xdp_size, bpf_xdp_copy);
3144 }
3145 
3146 static const struct bpf_func_proto bpf_xdp_event_output_proto = {
3147         .func           = bpf_xdp_event_output,
3148         .gpl_only       = true,
3149         .ret_type       = RET_INTEGER,
3150         .arg1_type      = ARG_PTR_TO_CTX,
3151         .arg2_type      = ARG_CONST_MAP_PTR,
3152         .arg3_type      = ARG_ANYTHING,
3153         .arg4_type      = ARG_PTR_TO_MEM,
3154         .arg5_type      = ARG_CONST_SIZE,
3155 };
3156 
3157 BPF_CALL_1(bpf_get_socket_cookie, struct sk_buff *, skb)
3158 {
3159         return skb->sk ? sock_gen_cookie(skb->sk) : 0;
3160 }
3161 
3162 static const struct bpf_func_proto bpf_get_socket_cookie_proto = {
3163         .func           = bpf_get_socket_cookie,
3164         .gpl_only       = false,
3165         .ret_type       = RET_INTEGER,
3166         .arg1_type      = ARG_PTR_TO_CTX,
3167 };
3168 
3169 BPF_CALL_1(bpf_get_socket_uid, struct sk_buff *, skb)
3170 {
3171         struct sock *sk = sk_to_full_sk(skb->sk);
3172         kuid_t kuid;
3173 
3174         if (!sk || !sk_fullsock(sk))
3175                 return overflowuid;
3176         kuid = sock_net_uid(sock_net(sk), sk);
3177         return from_kuid_munged(sock_net(sk)->user_ns, kuid);
3178 }
3179 
3180 static const struct bpf_func_proto bpf_get_socket_uid_proto = {
3181         .func           = bpf_get_socket_uid,
3182         .gpl_only       = false,
3183         .ret_type       = RET_INTEGER,
3184         .arg1_type      = ARG_PTR_TO_CTX,
3185 };
3186 
3187 BPF_CALL_5(bpf_setsockopt, struct bpf_sock_ops_kern *, bpf_sock,
3188            int, level, int, optname, char *, optval, int, optlen)
3189 {
3190         struct sock *sk = bpf_sock->sk;
3191         int ret = 0;
3192         int val;
3193 
3194         if (!sk_fullsock(sk))
3195                 return -EINVAL;
3196 
3197         if (level == SOL_SOCKET) {
3198                 if (optlen != sizeof(int))
3199                         return -EINVAL;
3200                 val = *((int *)optval);
3201 
3202                 /* Only some socketops are supported */
3203                 switch (optname) {
3204                 case SO_RCVBUF:
3205                         sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
3206                         sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF);
3207                         break;
3208                 case SO_SNDBUF:
3209                         sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
3210                         sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF);
3211                         break;
3212                 case SO_MAX_PACING_RATE:
3213                         sk->sk_max_pacing_rate = val;
3214                         sk->sk_pacing_rate = min(sk->sk_pacing_rate,
3215                                                  sk->sk_max_pacing_rate);
3216                         break;
3217                 case SO_PRIORITY:
3218                         sk->sk_priority = val;
3219                         break;
3220                 case SO_RCVLOWAT:
3221                         if (val < 0)
3222                                 val = INT_MAX;
3223                         sk->sk_rcvlowat = val ? : 1;
3224                         break;
3225                 case SO_MARK:
3226                         sk->sk_mark = val;
3227                         break;
3228                 default:
3229                         ret = -EINVAL;
3230                 }
3231 #ifdef CONFIG_INET
3232         } else if (level == SOL_TCP &&
3233                    sk->sk_prot->setsockopt == tcp_setsockopt) {
3234                 if (optname == TCP_CONGESTION) {
3235                         char name[TCP_CA_NAME_MAX];
3236                         bool reinit = bpf_sock->op > BPF_SOCK_OPS_NEEDS_ECN;
3237 
3238                         strncpy(name, optval, min_t(long, optlen,
3239                                                     TCP_CA_NAME_MAX-1));
3240                         name[TCP_CA_NAME_MAX-1] = 0;
3241                         ret = tcp_set_congestion_control(sk, name, false, reinit);
3242                 } else {
3243                         struct tcp_sock *tp = tcp_sk(sk);
3244 
3245                         if (optlen != sizeof(int))
3246                                 return -EINVAL;
3247 
3248                         val = *((int *)optval);
3249                         /* Only some options are supported */
3250                         switch (optname) {
3251                         case TCP_BPF_IW:
3252                                 if (val <= 0 || tp->data_segs_out > 0)
3253                                         ret = -EINVAL;
3254                                 else
3255                                         tp->snd_cwnd = val;
3256                                 break;
3257                         case TCP_BPF_SNDCWND_CLAMP:
3258                                 if (val <= 0) {
3259                                         ret = -EINVAL;
3260                                 } else {
3261                                         tp->snd_cwnd_clamp = val;
3262                                         tp->snd_ssthresh = val;
3263                                 }
3264                                 break;
3265                         default:
3266                                 ret = -EINVAL;
3267                         }
3268                 }
3269 #endif
3270         } else {
3271                 ret = -EINVAL;
3272         }
3273         return ret;
3274 }
3275 
3276 static const struct bpf_func_proto bpf_setsockopt_proto = {
3277         .func           = bpf_setsockopt,
3278         .gpl_only       = false,
3279         .ret_type       = RET_INTEGER,
3280         .arg1_type      = ARG_PTR_TO_CTX,
3281         .arg2_type      = ARG_ANYTHING,
3282         .arg3_type      = ARG_ANYTHING,
3283         .arg4_type      = ARG_PTR_TO_MEM,
3284         .arg5_type      = ARG_CONST_SIZE,
3285 };
3286 
3287 BPF_CALL_5(bpf_getsockopt, struct bpf_sock_ops_kern *, bpf_sock,
3288            int, level, int, optname, char *, optval, int, optlen)
3289 {
3290         struct sock *sk = bpf_sock->sk;
3291 
3292         if (!sk_fullsock(sk))
3293                 goto err_clear;
3294 
3295 #ifdef CONFIG_INET
3296         if (level == SOL_TCP && sk->sk_prot->getsockopt == tcp_getsockopt) {
3297                 if (optname == TCP_CONGESTION) {
3298                         struct inet_connection_sock *icsk = inet_csk(sk);
3299 
3300                         if (!icsk->icsk_ca_ops || optlen <= 1)
3301                                 goto err_clear;
3302                         strncpy(optval, icsk->icsk_ca_ops->name, optlen);
3303                         optval[optlen - 1] = 0;
3304                 } else {
3305                         goto err_clear;
3306                 }
3307         } else {
3308                 goto err_clear;
3309         }
3310         return 0;
3311 #endif
3312 err_clear:
3313         memset(optval, 0, optlen);
3314         return -EINVAL;
3315 }
3316 
3317 static const struct bpf_func_proto bpf_getsockopt_proto = {
3318         .func           = bpf_getsockopt,
3319         .gpl_only       = false,
3320         .ret_type       = RET_INTEGER,
3321         .arg1_type      = ARG_PTR_TO_CTX,
3322         .arg2_type      = ARG_ANYTHING,
3323         .arg3_type      = ARG_ANYTHING,
3324         .arg4_type      = ARG_PTR_TO_UNINIT_MEM,
3325         .arg5_type      = ARG_CONST_SIZE,
3326 };
3327 
3328 static const struct bpf_func_proto *
3329 bpf_base_func_proto(enum bpf_func_id func_id)
3330 {
3331         switch (func_id) {
3332         case BPF_FUNC_map_lookup_elem:
3333                 return &bpf_map_lookup_elem_proto;
3334         case BPF_FUNC_map_update_elem:
3335                 return &bpf_map_update_elem_proto;
3336         case BPF_FUNC_map_delete_elem:
3337                 return &bpf_map_delete_elem_proto;
3338         case BPF_FUNC_get_prandom_u32:
3339                 return &bpf_get_prandom_u32_proto;
3340         case BPF_FUNC_get_smp_processor_id:
3341                 return &bpf_get_raw_smp_processor_id_proto;
3342         case BPF_FUNC_get_numa_node_id:
3343                 return &bpf_get_numa_node_id_proto;
3344         case BPF_FUNC_tail_call:
3345                 return &bpf_tail_call_proto;
3346         case BPF_FUNC_ktime_get_ns:
3347                 return &bpf_ktime_get_ns_proto;
3348         case BPF_FUNC_trace_printk:
3349                 if (capable(CAP_SYS_ADMIN))
3350                         return bpf_get_trace_printk_proto();
3351         default:
3352                 return NULL;
3353         }
3354 }
3355 
3356 static const struct bpf_func_proto *
3357 sock_filter_func_proto(enum bpf_func_id func_id)
3358 {
3359         switch (func_id) {
3360         /* inet and inet6 sockets are created in a process
3361          * context so there is always a valid uid/gid
3362          */
3363         case BPF_FUNC_get_current_uid_gid:
3364                 return &bpf_get_current_uid_gid_proto;
3365         default:
3366                 return bpf_base_func_proto(func_id);
3367         }
3368 }
3369 
3370 static const struct bpf_func_proto *
3371 sk_filter_func_proto(enum bpf_func_id func_id)
3372 {
3373         switch (func_id) {
3374         case BPF_FUNC_skb_load_bytes:
3375                 return &bpf_skb_load_bytes_proto;
3376         case BPF_FUNC_get_socket_cookie:
3377                 return &bpf_get_socket_cookie_proto;
3378         case BPF_FUNC_get_socket_uid:
3379                 return &bpf_get_socket_uid_proto;
3380         default:
3381                 return bpf_base_func_proto(func_id);
3382         }
3383 }
3384 
3385 static const struct bpf_func_proto *
3386 tc_cls_act_func_proto(enum bpf_func_id func_id)
3387 {
3388         switch (func_id) {
3389         case BPF_FUNC_skb_store_bytes:
3390                 return &bpf_skb_store_bytes_proto;
3391         case BPF_FUNC_skb_load_bytes:
3392                 return &bpf_skb_load_bytes_proto;
3393         case BPF_FUNC_skb_pull_data:
3394                 return &bpf_skb_pull_data_proto;
3395         case BPF_FUNC_csum_diff:
3396                 return &bpf_csum_diff_proto;
3397         case BPF_FUNC_csum_update:
3398                 return &bpf_csum_update_proto;
3399         case BPF_FUNC_l3_csum_replace:
3400                 return &bpf_l3_csum_replace_proto;
3401         case BPF_FUNC_l4_csum_replace:
3402                 return &bpf_l4_csum_replace_proto;
3403         case BPF_FUNC_clone_redirect:
3404                 return &bpf_clone_redirect_proto;
3405         case BPF_FUNC_get_cgroup_classid:
3406                 return &bpf_get_cgroup_classid_proto;
3407         case BPF_FUNC_skb_vlan_push:
3408                 return &bpf_skb_vlan_push_proto;
3409         case BPF_FUNC_skb_vlan_pop:
3410                 return &bpf_skb_vlan_pop_proto;
3411         case BPF_FUNC_skb_change_proto:
3412                 return &bpf_skb_change_proto_proto;
3413         case BPF_FUNC_skb_change_type:
3414                 return &bpf_skb_change_type_proto;
3415         case BPF_FUNC_skb_adjust_room:
3416                 return &bpf_skb_adjust_room_proto;
3417         case BPF_FUNC_skb_change_tail:
3418                 return &bpf_skb_change_tail_proto;
3419         case BPF_FUNC_skb_get_tunnel_key:
3420                 return &bpf_skb_get_tunnel_key_proto;
3421         case BPF_FUNC_skb_set_tunnel_key:
3422                 return bpf_get_skb_set_tunnel_proto(func_id);
3423         case BPF_FUNC_skb_get_tunnel_opt:
3424                 return &bpf_skb_get_tunnel_opt_proto;
3425         case BPF_FUNC_skb_set_tunnel_opt:
3426                 return bpf_get_skb_set_tunnel_proto(func_id);
3427         case BPF_FUNC_redirect:
3428                 return &bpf_redirect_proto;
3429         case BPF_FUNC_get_route_realm:
3430                 return &bpf_get_route_realm_proto;
3431         case BPF_FUNC_get_hash_recalc:
3432                 return &bpf_get_hash_recalc_proto;
3433         case BPF_FUNC_set_hash_invalid:
3434                 return &bpf_set_hash_invalid_proto;
3435         case BPF_FUNC_set_hash:
3436                 return &bpf_set_hash_proto;
3437         case BPF_FUNC_perf_event_output:
3438                 return &bpf_skb_event_output_proto;
3439         case BPF_FUNC_get_smp_processor_id:
3440                 return &bpf_get_smp_processor_id_proto;
3441         case BPF_FUNC_skb_under_cgroup:
3442                 return &bpf_skb_under_cgroup_proto;
3443         case BPF_FUNC_get_socket_cookie:
3444                 return &bpf_get_socket_cookie_proto;
3445         case BPF_FUNC_get_socket_uid:
3446                 return &bpf_get_socket_uid_proto;
3447         default:
3448                 return bpf_base_func_proto(func_id);
3449         }
3450 }
3451 
3452 static const struct bpf_func_proto *
3453 xdp_func_proto(enum bpf_func_id func_id)
3454 {
3455         switch (func_id) {
3456         case BPF_FUNC_perf_event_output:
3457                 return &bpf_xdp_event_output_proto;
3458         case BPF_FUNC_get_smp_processor_id:
3459                 return &bpf_get_smp_processor_id_proto;
3460         case BPF_FUNC_xdp_adjust_head:
3461                 return &bpf_xdp_adjust_head_proto;
3462         case BPF_FUNC_xdp_adjust_meta:
3463                 return &bpf_xdp_adjust_meta_proto;
3464         case BPF_FUNC_redirect:
3465                 return &bpf_xdp_redirect_proto;
3466         case BPF_FUNC_redirect_map:
3467                 return &bpf_xdp_redirect_map_proto;
3468         default:
3469                 return bpf_base_func_proto(func_id);
3470         }
3471 }
3472 
3473 static const struct bpf_func_proto *
3474 lwt_inout_func_proto(enum bpf_func_id func_id)
3475 {
3476         switch (func_id) {
3477         case BPF_FUNC_skb_load_bytes:
3478                 return &bpf_skb_load_bytes_proto;
3479         case BPF_FUNC_skb_pull_data:
3480                 return &bpf_skb_pull_data_proto;
3481         case BPF_FUNC_csum_diff:
3482                 return &bpf_csum_diff_proto;
3483         case BPF_FUNC_get_cgroup_classid:
3484                 return &bpf_get_cgroup_classid_proto;
3485         case BPF_FUNC_get_route_realm:
3486                 return &bpf_get_route_realm_proto;
3487         case BPF_FUNC_get_hash_recalc:
3488                 return &bpf_get_hash_recalc_proto;
3489         case BPF_FUNC_perf_event_output:
3490                 return &bpf_skb_event_output_proto;
3491         case BPF_FUNC_get_smp_processor_id:
3492                 return &bpf_get_smp_processor_id_proto;
3493         case BPF_FUNC_skb_under_cgroup:
3494                 return &bpf_skb_under_cgroup_proto;
3495         default:
3496                 return bpf_base_func_proto(func_id);
3497         }
3498 }
3499 
3500 static const struct bpf_func_proto *
3501         sock_ops_func_proto(enum bpf_func_id func_id)
3502 {
3503         switch (func_id) {
3504         case BPF_FUNC_setsockopt:
3505                 return &bpf_setsockopt_proto;
3506         case BPF_FUNC_getsockopt:
3507                 return &bpf_getsockopt_proto;
3508         case BPF_FUNC_sock_map_update:
3509                 return &bpf_sock_map_update_proto;
3510         default:
3511                 return bpf_base_func_proto(func_id);
3512         }
3513 }
3514 
3515 static const struct bpf_func_proto *sk_skb_func_proto(enum bpf_func_id func_id)
3516 {
3517         switch (func_id) {
3518         case BPF_FUNC_skb_store_bytes:
3519                 return &bpf_skb_store_bytes_proto;
3520         case BPF_FUNC_skb_load_bytes:
3521                 return &bpf_skb_load_bytes_proto;
3522         case BPF_FUNC_skb_pull_data:
3523                 return &bpf_skb_pull_data_proto;
3524         case BPF_FUNC_skb_change_tail:
3525                 return &bpf_skb_change_tail_proto;
3526         case BPF_FUNC_skb_change_head:
3527                 return &bpf_skb_change_head_proto;
3528         case BPF_FUNC_get_socket_cookie:
3529                 return &bpf_get_socket_cookie_proto;
3530         case BPF_FUNC_get_socket_uid:
3531                 return &bpf_get_socket_uid_proto;
3532         case BPF_FUNC_sk_redirect_map:
3533                 return &bpf_sk_redirect_map_proto;
3534         default:
3535                 return bpf_base_func_proto(func_id);
3536         }
3537 }
3538 
3539 static const struct bpf_func_proto *
3540 lwt_xmit_func_proto(enum bpf_func_id func_id)
3541 {
3542         switch (func_id) {
3543         case BPF_FUNC_skb_get_tunnel_key:
3544                 return &bpf_skb_get_tunnel_key_proto;
3545         case BPF_FUNC_skb_set_tunnel_key:
3546                 return bpf_get_skb_set_tunnel_proto(func_id);
3547         case BPF_FUNC_skb_get_tunnel_opt:
3548                 return &bpf_skb_get_tunnel_opt_proto;
3549         case BPF_FUNC_skb_set_tunnel_opt:
3550                 return bpf_get_skb_set_tunnel_proto(func_id);
3551         case BPF_FUNC_redirect:
3552                 return &bpf_redirect_proto;
3553         case BPF_FUNC_clone_redirect:
3554                 return &bpf_clone_redirect_proto;
3555         case BPF_FUNC_skb_change_tail:
3556                 return &bpf_skb_change_tail_proto;
3557         case BPF_FUNC_skb_change_head:
3558                 return &bpf_skb_change_head_proto;
3559         case BPF_FUNC_skb_store_bytes:
3560                 return &bpf_skb_store_bytes_proto;
3561         case BPF_FUNC_csum_update:
3562                 return &bpf_csum_update_proto;
3563         case BPF_FUNC_l3_csum_replace:
3564                 return &bpf_l3_csum_replace_proto;
3565         case BPF_FUNC_l4_csum_replace:
3566                 return &bpf_l4_csum_replace_proto;
3567         case BPF_FUNC_set_hash_invalid:
3568                 return &bpf_set_hash_invalid_proto;
3569         default:
3570                 return lwt_inout_func_proto(func_id);
3571         }
3572 }
3573 
3574 static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type,
3575                                     struct bpf_insn_access_aux *info)
3576 {
3577         const int size_default = sizeof(__u32);
3578 
3579         if (off < 0 || off >= sizeof(struct __sk_buff))
3580                 return false;
3581 
3582         /* The verifier guarantees that size > 0. */
3583         if (off % size != 0)
3584                 return false;
3585 
3586         switch (off) {
3587         case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
3588                 if (off + size > offsetofend(struct __sk_buff, cb[4]))
3589                         return false;
3590                 break;
3591         case bpf_ctx_range_till(struct __sk_buff, remote_ip6[0], remote_ip6[3]):
3592         case bpf_ctx_range_till(struct __sk_buff, local_ip6[0], local_ip6[3]):
3593         case bpf_ctx_range_till(struct __sk_buff, remote_ip4, remote_ip4):
3594         case bpf_ctx_range_till(struct __sk_buff, local_ip4, local_ip4):
3595         case bpf_ctx_range(struct __sk_buff, data):
3596         case bpf_ctx_range(struct __sk_buff, data_meta):
3597         case bpf_ctx_range(struct __sk_buff, data_end):
3598                 if (size != size_default)
3599                         return false;
3600                 break;
3601         default:
3602                 /* Only narrow read access allowed for now. */
3603                 if (type == BPF_WRITE) {
3604                         if (size != size_default)
3605                                 return false;
3606                 } else {
3607                         bpf_ctx_record_field_size(info, size_default);
3608                         if (!bpf_ctx_narrow_access_ok(off, size, size_default))
3609                                 return false;
3610                 }
3611         }
3612 
3613         return true;
3614 }
3615 
3616 static bool sk_filter_is_valid_access(int off, int size,
3617                                       enum bpf_access_type type,
3618                                       struct bpf_insn_access_aux *info)
3619 {
3620         switch (off) {
3621         case bpf_ctx_range(struct __sk_buff, tc_classid):
3622         case bpf_ctx_range(struct __sk_buff, data):
3623         case bpf_ctx_range(struct __sk_buff, data_meta):
3624         case bpf_ctx_range(struct __sk_buff, data_end):
3625         case bpf_ctx_range_till(struct __sk_buff, family, local_port):
3626                 return false;
3627         }
3628 
3629         if (type == BPF_WRITE) {
3630                 switch (off) {
3631                 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
3632                         break;
3633                 default:
3634                         return false;
3635                 }
3636         }
3637 
3638         return bpf_skb_is_valid_access(off, size, type, info);
3639 }
3640 
3641 static bool lwt_is_valid_access(int off, int size,
3642                                 enum bpf_access_type type,
3643                                 struct bpf_insn_access_aux *info)
3644 {
3645         switch (off) {
3646         case bpf_ctx_range(struct __sk_buff, tc_classid):
3647         case bpf_ctx_range_till(struct __sk_buff, family, local_port):
3648         case bpf_ctx_range(struct __sk_buff, data_meta):
3649                 return false;
3650         }
3651 
3652         if (type == BPF_WRITE) {
3653                 switch (off) {
3654                 case bpf_ctx_range(struct __sk_buff, mark):
3655                 case bpf_ctx_range(struct __sk_buff, priority):
3656                 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
3657                         break;
3658                 default:
3659                         return false;
3660                 }
3661         }
3662 
3663         switch (off) {
3664         case bpf_ctx_range(struct __sk_buff, data):
3665                 info->reg_type = PTR_TO_PACKET;
3666                 break;
3667         case bpf_ctx_range(struct __sk_buff, data_end):
3668                 info->reg_type = PTR_TO_PACKET_END;
3669                 break;
3670         }
3671 
3672         return bpf_skb_is_valid_access(off, size, type, info);
3673 }
3674 
3675 static bool sock_filter_is_valid_access(int off, int size,
3676                                         enum bpf_access_type type,
3677                                         struct bpf_insn_access_aux *info)
3678 {
3679         if (type == BPF_WRITE) {
3680                 switch (off) {
3681                 case offsetof(struct bpf_sock, bound_dev_if):
3682                 case offsetof(struct bpf_sock, mark):
3683                 case offsetof(struct bpf_sock, priority):
3684                         break;
3685                 default:
3686                         return false;
3687                 }
3688         }
3689 
3690         if (off < 0 || off + size > sizeof(struct bpf_sock))
3691                 return false;
3692         /* The verifier guarantees that size > 0. */
3693         if (off % size != 0)
3694                 return false;
3695         if (size != sizeof(__u32))
3696                 return false;
3697 
3698         return true;
3699 }
3700 
3701 static int bpf_unclone_prologue(struct bpf_insn *insn_buf, bool direct_write,
3702                                 const struct bpf_prog *prog, int drop_verdict)
3703 {
3704         struct bpf_insn *insn = insn_buf;
3705 
3706         if (!direct_write)
3707                 return 0;
3708 
3709         /* if (!skb->cloned)
3710          *       goto start;
3711          *
3712          * (Fast-path, otherwise approximation that we might be
3713          *  a clone, do the rest in helper.)
3714          */
3715         *insn++ = BPF_LDX_MEM(BPF_B, BPF_REG_6, BPF_REG_1, CLONED_OFFSET());
3716         *insn++ = BPF_ALU32_IMM(BPF_AND, BPF_REG_6, CLONED_MASK);
3717         *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_6, 0, 7);
3718 
3719         /* ret = bpf_skb_pull_data(skb, 0); */
3720         *insn++ = BPF_MOV64_REG(BPF_REG_6, BPF_REG_1);
3721         *insn++ = BPF_ALU64_REG(BPF_XOR, BPF_REG_2, BPF_REG_2);
3722         *insn++ = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
3723                                BPF_FUNC_skb_pull_data);
3724         /* if (!ret)
3725          *      goto restore;
3726          * return TC_ACT_SHOT;
3727          */
3728         *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2);
3729         *insn++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_0, drop_verdict);
3730         *insn++ = BPF_EXIT_INSN();
3731 
3732         /* restore: */
3733         *insn++ = BPF_MOV64_REG(BPF_REG_1, BPF_REG_6);
3734         /* start: */
3735         *insn++ = prog->insnsi[0];
3736 
3737         return insn - insn_buf;
3738 }
3739 
3740 static int tc_cls_act_prologue(struct bpf_insn *insn_buf, bool direct_write,
3741                                const struct bpf_prog *prog)
3742 {
3743         return bpf_unclone_prologue(insn_buf, direct_write, prog, TC_ACT_SHOT);
3744 }
3745 
3746 static bool tc_cls_act_is_valid_access(int off, int size,
3747                                        enum bpf_access_type type,
3748                                        struct bpf_insn_access_aux *info)
3749 {
3750         if (type == BPF_WRITE) {
3751                 switch (off) {
3752                 case bpf_ctx_range(struct __sk_buff, mark):
3753                 case bpf_ctx_range(struct __sk_buff, tc_index):
3754                 case bpf_ctx_range(struct __sk_buff, priority):
3755                 case bpf_ctx_range(struct __sk_buff, tc_classid):
3756                 case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
3757                         break;
3758                 default:
3759                         return false;
3760                 }
3761         }
3762 
3763         switch (off) {
3764         case bpf_ctx_range(struct __sk_buff, data):
3765                 info->reg_type = PTR_TO_PACKET;
3766                 break;
3767         case bpf_ctx_range(struct __sk_buff, data_meta):
3768                 info->reg_type = PTR_TO_PACKET_META;
3769                 break;
3770         case bpf_ctx_range(struct __sk_buff, data_end):
3771                 info->reg_type = PTR_TO_PACKET_END;
3772                 break;
3773         case bpf_ctx_range_till(struct __sk_buff, family, local_port):
3774                 return false;
3775         }
3776 
3777         return bpf_skb_is_valid_access(off, size, type, info);
3778 }
3779 
3780 static bool __is_valid_xdp_access(int off, int size)
3781 {
3782         if (off < 0 || off >= sizeof(struct xdp_md))
3783                 return false;
3784         if (off % size != 0)
3785                 return false;
3786         if (size != sizeof(__u32))
3787                 return false;
3788 
3789         return true;
3790 }
3791 
3792 static bool xdp_is_valid_access(int off, int size,
3793                                 enum bpf_access_type type,
3794                                 struct bpf_insn_access_aux *info)
3795 {
3796         if (type == BPF_WRITE)
3797                 return false;
3798 
3799         switch (off) {
3800         case offsetof(struct xdp_md, data):
3801                 info->reg_type = PTR_TO_PACKET;
3802                 break;
3803         case offsetof(struct xdp_md, data_meta):
3804                 info->reg_type = PTR_TO_PACKET_META;
3805                 break;
3806         case offsetof(struct xdp_md, data_end):
3807                 info->reg_type = PTR_TO_PACKET_END;
3808                 break;
3809         }
3810 
3811         return __is_valid_xdp_access(off, size);
3812 }
3813 
3814 void bpf_warn_invalid_xdp_action(u32 act)
3815 {
3816         const u32 act_max = XDP_REDIRECT;
3817 
3818         WARN_ONCE(1, "%s XDP return value %u, expect packet loss!\n",
3819                   act > act_max ? "Illegal" : "Driver unsupported",
3820                   act);
3821 }
3822 EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action);
3823 
3824 static bool __is_valid_sock_ops_access(int off, int size)
3825 {
3826         if (off < 0 || off >= sizeof(struct bpf_sock_ops))
3827                 return false;
3828         /* The verifier guarantees that size > 0. */
3829         if (off % size != 0)
3830                 return false;
3831         if (size != sizeof(__u32))
3832                 return false;
3833 
3834         return true;
3835 }
3836 
3837 static bool sock_ops_is_valid_access(int off, int size,
3838                                      enum bpf_access_type type,
3839                                      struct bpf_insn_access_aux *info)
3840 {
3841         if (type == BPF_WRITE) {
3842                 switch (off) {
3843                 case offsetof(struct bpf_sock_ops, op) ...
3844                      offsetof(struct bpf_sock_ops, replylong[3]):
3845                         break;
3846                 default:
3847                         return false;
3848                 }
3849         }
3850 
3851         return __is_valid_sock_ops_access(off, size);
3852 }
3853 
3854 static int sk_skb_prologue(struct bpf_insn *insn_buf, bool direct_write,
3855                            const struct bpf_prog *prog)
3856 {
3857         return bpf_unclone_prologue(insn_buf, direct_write, prog, SK_DROP);
3858 }
3859 
3860 static bool sk_skb_is_valid_access(int off, int size,
3861                                    enum bpf_access_type type,
3862                                    struct bpf_insn_access_aux *info)
3863 {
3864         switch (off) {
3865         case bpf_ctx_range(struct __sk_buff, tc_classid):
3866         case bpf_ctx_range(struct __sk_buff, data_meta):
3867                 return false;
3868         }
3869 
3870         if (type == BPF_WRITE) {
3871                 switch (off) {
3872                 case bpf_ctx_range(struct __sk_buff, tc_index):
3873                 case bpf_ctx_range(struct __sk_buff, priority):
3874                         break;
3875                 default:
3876                         return false;
3877                 }
3878         }
3879 
3880         switch (off) {
3881         case bpf_ctx_range(struct __sk_buff, mark):
3882                 return false;
3883         case bpf_ctx_range(struct __sk_buff, data):
3884                 info->reg_type = PTR_TO_PACKET;
3885                 break;
3886         case bpf_ctx_range(struct __sk_buff, data_end):
3887                 info->reg_type = PTR_TO_PACKET_END;
3888                 break;
3889         }
3890 
3891         return bpf_skb_is_valid_access(off, size, type, info);
3892 }
3893 
3894 static u32 bpf_convert_ctx_access(enum bpf_access_type type,
3895                                   const struct bpf_insn *si,
3896                                   struct bpf_insn *insn_buf,
3897                                   struct bpf_prog *prog, u32 *target_size)
3898 {
3899         struct bpf_insn *insn = insn_buf;
3900         int off;
3901 
3902         switch (si->off) {
3903         case offsetof(struct __sk_buff, len):
3904                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
3905                                       bpf_target_off(struct sk_buff, len, 4,
3906                                                      target_size));
3907                 break;
3908 
3909         case offsetof(struct __sk_buff, protocol):
3910                 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
3911                                       bpf_target_off(struct sk_buff, protocol, 2,
3912                                                      target_size));
3913                 break;
3914 
3915         case offsetof(struct __sk_buff, vlan_proto):
3916                 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
3917                                       bpf_target_off(struct sk_buff, vlan_proto, 2,
3918                                                      target_size));
3919                 break;
3920 
3921         case offsetof(struct __sk_buff, priority):
3922                 if (type == BPF_WRITE)
3923                         *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
3924                                               bpf_target_off(struct sk_buff, priority, 4,
3925                                                              target_size));
3926                 else
3927                         *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
3928                                               bpf_target_off(struct sk_buff, priority, 4,
3929                                                              target_size));
3930                 break;
3931 
3932         case offsetof(struct __sk_buff, ingress_ifindex):
3933                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
3934                                       bpf_target_off(struct sk_buff, skb_iif, 4,
3935                                                      target_size));
3936                 break;
3937 
3938         case offsetof(struct __sk_buff, ifindex):
3939                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
3940                                       si->dst_reg, si->src_reg,
3941                                       offsetof(struct sk_buff, dev));
3942                 *insn++ = BPF_JMP_IMM(BPF_JEQ, si->dst_reg, 0, 1);
3943                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
3944                                       bpf_target_off(struct net_device, ifindex, 4,
3945                                                      target_size));
3946                 break;
3947 
3948         case offsetof(struct __sk_buff, hash):
3949                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
3950                                       bpf_target_off(struct sk_buff, hash, 4,
3951                                                      target_size));
3952                 break;
3953 
3954         case offsetof(struct __sk_buff, mark):
3955                 if (type == BPF_WRITE)
3956                         *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
3957                                               bpf_target_off(struct sk_buff, mark, 4,
3958                                                              target_size));
3959                 else
3960                         *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
3961                                               bpf_target_off(struct sk_buff, mark, 4,
3962                                                              target_size));
3963                 break;
3964 
3965         case offsetof(struct __sk_buff, pkt_type):
3966                 *target_size = 1;
3967                 *insn++ = BPF_LDX_MEM(BPF_B, si->dst_reg, si->src_reg,
3968                                       PKT_TYPE_OFFSET());
3969                 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, PKT_TYPE_MAX);
3970 #ifdef __BIG_ENDIAN_BITFIELD
3971                 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 5);
3972 #endif
3973                 break;
3974 
3975         case offsetof(struct __sk_buff, queue_mapping):
3976                 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
3977                                       bpf_target_off(struct sk_buff, queue_mapping, 2,
3978                                                      target_size));
3979                 break;
3980 
3981         case offsetof(struct __sk_buff, vlan_present):
3982         case offsetof(struct __sk_buff, vlan_tci):
3983                 BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000);
3984 
3985                 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
3986                                       bpf_target_off(struct sk_buff, vlan_tci, 2,
3987                                                      target_size));
3988                 if (si->off == offsetof(struct __sk_buff, vlan_tci)) {
3989                         *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg,
3990                                                 ~VLAN_TAG_PRESENT);
3991                 } else {
3992                         *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, 12);
3993                         *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, 1);
3994                 }
3995                 break;
3996 
3997         case offsetof(struct __sk_buff, cb[0]) ...
3998              offsetofend(struct __sk_buff, cb[4]) - 1:
3999                 BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, data) < 20);
4000                 BUILD_BUG_ON((offsetof(struct sk_buff, cb) +
4001                               offsetof(struct qdisc_skb_cb, data)) %
4002                              sizeof(__u64));
4003 
4004                 prog->cb_access = 1;
4005                 off  = si->off;
4006                 off -= offsetof(struct __sk_buff, cb[0]);
4007                 off += offsetof(struct sk_buff, cb);
4008                 off += offsetof(struct qdisc_skb_cb, data);
4009                 if (type == BPF_WRITE)
4010                         *insn++ = BPF_STX_MEM(BPF_SIZE(si->code), si->dst_reg,
4011                                               si->src_reg, off);
4012                 else
4013                         *insn++ = BPF_LDX_MEM(BPF_SIZE(si->code), si->dst_reg,
4014                                               si->src_reg, off);
4015                 break;
4016 
4017         case offsetof(struct __sk_buff, tc_classid):
4018                 BUILD_BUG_ON(FIELD_SIZEOF(struct qdisc_skb_cb, tc_classid) != 2);
4019 
4020                 off  = si->off;
4021                 off -= offsetof(struct __sk_buff, tc_classid);
4022                 off += offsetof(struct sk_buff, cb);
4023                 off += offsetof(struct qdisc_skb_cb, tc_classid);
4024                 *target_size = 2;
4025                 if (type == BPF_WRITE)
4026                         *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg,
4027                                               si->src_reg, off);
4028                 else
4029                         *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg,
4030                                               si->src_reg, off);
4031                 break;
4032 
4033         case offsetof(struct __sk_buff, data):
4034                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, data),
4035                                       si->dst_reg, si->src_reg,
4036                                       offsetof(struct sk_buff, data));
4037                 break;
4038 
4039         case offsetof(struct __sk_buff, data_meta):
4040                 off  = si->off;
4041                 off -= offsetof(struct __sk_buff, data_meta);
4042                 off += offsetof(struct sk_buff, cb);
4043                 off += offsetof(struct bpf_skb_data_end, data_meta);
4044                 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
4045                                       si->src_reg, off);
4046                 break;
4047 
4048         case offsetof(struct __sk_buff, data_end):
4049                 off  = si->off;
4050                 off -= offsetof(struct __sk_buff, data_end);
4051                 off += offsetof(struct sk_buff, cb);
4052                 off += offsetof(struct bpf_skb_data_end, data_end);
4053                 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
4054                                       si->src_reg, off);
4055                 break;
4056 
4057         case offsetof(struct __sk_buff, tc_index):
4058 #ifdef CONFIG_NET_SCHED
4059                 if (type == BPF_WRITE)
4060                         *insn++ = BPF_STX_MEM(BPF_H, si->dst_reg, si->src_reg,
4061                                               bpf_target_off(struct sk_buff, tc_index, 2,
4062                                                              target_size));
4063                 else
4064                         *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
4065                                               bpf_target_off(struct sk_buff, tc_index, 2,
4066                                                              target_size));
4067 #else
4068                 *target_size = 2;
4069                 if (type == BPF_WRITE)
4070                         *insn++ = BPF_MOV64_REG(si->dst_reg, si->dst_reg);
4071                 else
4072                         *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
4073 #endif
4074                 break;
4075 
4076         case offsetof(struct __sk_buff, napi_id):
4077 #if defined(CONFIG_NET_RX_BUSY_POLL)
4078                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4079                                       bpf_target_off(struct sk_buff, napi_id, 4,
4080                                                      target_size));
4081                 *insn++ = BPF_JMP_IMM(BPF_JGE, si->dst_reg, MIN_NAPI_ID, 1);
4082                 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
4083 #else
4084                 *target_size = 4;
4085                 *insn++ = BPF_MOV64_IMM(si->dst_reg, 0);
4086 #endif
4087                 break;
4088         case offsetof(struct __sk_buff, family):
4089                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2);
4090 
4091                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
4092                                       si->dst_reg, si->src_reg,
4093                                       offsetof(struct sk_buff, sk));
4094                 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
4095                                       bpf_target_off(struct sock_common,
4096                                                      skc_family,
4097                                                      2, target_size));
4098                 break;
4099         case offsetof(struct __sk_buff, remote_ip4):
4100                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4);
4101 
4102                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
4103                                       si->dst_reg, si->src_reg,
4104                                       offsetof(struct sk_buff, sk));
4105                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4106                                       bpf_target_off(struct sock_common,
4107                                                      skc_daddr,
4108                                                      4, target_size));
4109                 break;
4110         case offsetof(struct __sk_buff, local_ip4):
4111                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
4112                                           skc_rcv_saddr) != 4);
4113 
4114                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
4115                                       si->dst_reg, si->src_reg,
4116                                       offsetof(struct sk_buff, sk));
4117                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4118                                       bpf_target_off(struct sock_common,
4119                                                      skc_rcv_saddr,
4120                                                      4, target_size));
4121                 break;
4122         case offsetof(struct __sk_buff, remote_ip6[0]) ...
4123              offsetof(struct __sk_buff, remote_ip6[3]):
4124 #if IS_ENABLED(CONFIG_IPV6)
4125                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
4126                                           skc_v6_daddr.s6_addr32[0]) != 4);
4127 
4128                 off = si->off;
4129                 off -= offsetof(struct __sk_buff, remote_ip6[0]);
4130 
4131                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
4132                                       si->dst_reg, si->src_reg,
4133                                       offsetof(struct sk_buff, sk));
4134                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4135                                       offsetof(struct sock_common,
4136                                                skc_v6_daddr.s6_addr32[0]) +
4137                                       off);
4138 #else
4139                 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
4140 #endif
4141                 break;
4142         case offsetof(struct __sk_buff, local_ip6[0]) ...
4143              offsetof(struct __sk_buff, local_ip6[3]):
4144 #if IS_ENABLED(CONFIG_IPV6)
4145                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
4146                                           skc_v6_rcv_saddr.s6_addr32[0]) != 4);
4147 
4148                 off = si->off;
4149                 off -= offsetof(struct __sk_buff, local_ip6[0]);
4150 
4151                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
4152                                       si->dst_reg, si->src_reg,
4153                                       offsetof(struct sk_buff, sk));
4154                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4155                                       offsetof(struct sock_common,
4156                                                skc_v6_rcv_saddr.s6_addr32[0]) +
4157                                       off);
4158 #else
4159                 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
4160 #endif
4161                 break;
4162 
4163         case offsetof(struct __sk_buff, remote_port):
4164                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2);
4165 
4166                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
4167                                       si->dst_reg, si->src_reg,
4168                                       offsetof(struct sk_buff, sk));
4169                 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
4170                                       bpf_target_off(struct sock_common,
4171                                                      skc_dport,
4172                                                      2, target_size));
4173 #ifndef __BIG_ENDIAN_BITFIELD
4174                 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
4175 #endif
4176                 break;
4177 
4178         case offsetof(struct __sk_buff, local_port):
4179                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2);
4180 
4181                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, sk),
4182                                       si->dst_reg, si->src_reg,
4183                                       offsetof(struct sk_buff, sk));
4184                 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
4185                                       bpf_target_off(struct sock_common,
4186                                                      skc_num, 2, target_size));
4187                 break;
4188         }
4189 
4190         return insn - insn_buf;
4191 }
4192 
4193 static u32 sock_filter_convert_ctx_access(enum bpf_access_type type,
4194                                           const struct bpf_insn *si,
4195                                           struct bpf_insn *insn_buf,
4196                                           struct bpf_prog *prog, u32 *target_size)
4197 {
4198         struct bpf_insn *insn = insn_buf;
4199 
4200         switch (si->off) {
4201         case offsetof(struct bpf_sock, bound_dev_if):
4202                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_bound_dev_if) != 4);
4203 
4204                 if (type == BPF_WRITE)
4205                         *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
4206                                         offsetof(struct sock, sk_bound_dev_if));
4207                 else
4208                         *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4209                                       offsetof(struct sock, sk_bound_dev_if));
4210                 break;
4211 
4212         case offsetof(struct bpf_sock, mark):
4213                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_mark) != 4);
4214 
4215                 if (type == BPF_WRITE)
4216                         *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
4217                                         offsetof(struct sock, sk_mark));
4218                 else
4219                         *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4220                                       offsetof(struct sock, sk_mark));
4221                 break;
4222 
4223         case offsetof(struct bpf_sock, priority):
4224                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_priority) != 4);
4225 
4226                 if (type == BPF_WRITE)
4227                         *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
4228                                         offsetof(struct sock, sk_priority));
4229                 else
4230                         *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4231                                       offsetof(struct sock, sk_priority));
4232                 break;
4233 
4234         case offsetof(struct bpf_sock, family):
4235                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock, sk_family) != 2);
4236 
4237                 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg,
4238                                       offsetof(struct sock, sk_family));
4239                 break;
4240 
4241         case offsetof(struct bpf_sock, type):
4242                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4243                                       offsetof(struct sock, __sk_flags_offset));
4244                 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_TYPE_MASK);
4245                 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_TYPE_SHIFT);
4246                 break;
4247 
4248         case offsetof(struct bpf_sock, protocol):
4249                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4250                                       offsetof(struct sock, __sk_flags_offset));
4251                 *insn++ = BPF_ALU32_IMM(BPF_AND, si->dst_reg, SK_FL_PROTO_MASK);
4252                 *insn++ = BPF_ALU32_IMM(BPF_RSH, si->dst_reg, SK_FL_PROTO_SHIFT);
4253                 break;
4254         }
4255 
4256         return insn - insn_buf;
4257 }
4258 
4259 static u32 tc_cls_act_convert_ctx_access(enum bpf_access_type type,
4260                                          const struct bpf_insn *si,
4261                                          struct bpf_insn *insn_buf,
4262                                          struct bpf_prog *prog, u32 *target_size)
4263 {
4264         struct bpf_insn *insn = insn_buf;
4265 
4266         switch (si->off) {
4267         case offsetof(struct __sk_buff, ifindex):
4268                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct sk_buff, dev),
4269                                       si->dst_reg, si->src_reg,
4270                                       offsetof(struct sk_buff, dev));
4271                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4272                                       bpf_target_off(struct net_device, ifindex, 4,
4273                                                      target_size));
4274                 break;
4275         default:
4276                 return bpf_convert_ctx_access(type, si, insn_buf, prog,
4277                                               target_size);
4278         }
4279 
4280         return insn - insn_buf;
4281 }
4282 
4283 static u32 xdp_convert_ctx_access(enum bpf_access_type type,
4284                                   const struct bpf_insn *si,
4285                                   struct bpf_insn *insn_buf,
4286                                   struct bpf_prog *prog, u32 *target_size)
4287 {
4288         struct bpf_insn *insn = insn_buf;
4289 
4290         switch (si->off) {
4291         case offsetof(struct xdp_md, data):
4292                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data),
4293                                       si->dst_reg, si->src_reg,
4294                                       offsetof(struct xdp_buff, data));
4295                 break;
4296         case offsetof(struct xdp_md, data_meta):
4297                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_meta),
4298                                       si->dst_reg, si->src_reg,
4299                                       offsetof(struct xdp_buff, data_meta));
4300                 break;
4301         case offsetof(struct xdp_md, data_end):
4302                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(struct xdp_buff, data_end),
4303                                       si->dst_reg, si->src_reg,
4304                                       offsetof(struct xdp_buff, data_end));
4305                 break;
4306         }
4307 
4308         return insn - insn_buf;
4309 }
4310 
4311 static u32 sock_ops_convert_ctx_access(enum bpf_access_type type,
4312                                        const struct bpf_insn *si,
4313                                        struct bpf_insn *insn_buf,
4314                                        struct bpf_prog *prog,
4315                                        u32 *target_size)
4316 {
4317         struct bpf_insn *insn = insn_buf;
4318         int off;
4319 
4320         switch (si->off) {
4321         case offsetof(struct bpf_sock_ops, op) ...
4322              offsetof(struct bpf_sock_ops, replylong[3]):
4323                 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, op) !=
4324                              FIELD_SIZEOF(struct bpf_sock_ops_kern, op));
4325                 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, reply) !=
4326                              FIELD_SIZEOF(struct bpf_sock_ops_kern, reply));
4327                 BUILD_BUG_ON(FIELD_SIZEOF(struct bpf_sock_ops, replylong) !=
4328                              FIELD_SIZEOF(struct bpf_sock_ops_kern, replylong));
4329                 off = si->off;
4330                 off -= offsetof(struct bpf_sock_ops, op);
4331                 off += offsetof(struct bpf_sock_ops_kern, op);
4332                 if (type == BPF_WRITE)
4333                         *insn++ = BPF_STX_MEM(BPF_W, si->dst_reg, si->src_reg,
4334                                               off);
4335                 else
4336                         *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg,
4337                                               off);
4338                 break;
4339 
4340         case offsetof(struct bpf_sock_ops, family):
4341                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_family) != 2);
4342 
4343                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
4344                                               struct bpf_sock_ops_kern, sk),
4345                                       si->dst_reg, si->src_reg,
4346                                       offsetof(struct bpf_sock_ops_kern, sk));
4347                 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
4348                                       offsetof(struct sock_common, skc_family));
4349                 break;
4350 
4351         case offsetof(struct bpf_sock_ops, remote_ip4):
4352                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_daddr) != 4);
4353 
4354                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
4355                                                 struct bpf_sock_ops_kern, sk),
4356                                       si->dst_reg, si->src_reg,
4357                                       offsetof(struct bpf_sock_ops_kern, sk));
4358                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4359                                       offsetof(struct sock_common, skc_daddr));
4360                 break;
4361 
4362         case offsetof(struct bpf_sock_ops, local_ip4):
4363                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_rcv_saddr) != 4);
4364 
4365                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
4366                                               struct bpf_sock_ops_kern, sk),
4367                                       si->dst_reg, si->src_reg,
4368                                       offsetof(struct bpf_sock_ops_kern, sk));
4369                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4370                                       offsetof(struct sock_common,
4371                                                skc_rcv_saddr));
4372                 break;
4373 
4374         case offsetof(struct bpf_sock_ops, remote_ip6[0]) ...
4375              offsetof(struct bpf_sock_ops, remote_ip6[3]):
4376 #if IS_ENABLED(CONFIG_IPV6)
4377                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
4378                                           skc_v6_daddr.s6_addr32[0]) != 4);
4379 
4380                 off = si->off;
4381                 off -= offsetof(struct bpf_sock_ops, remote_ip6[0]);
4382                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
4383                                                 struct bpf_sock_ops_kern, sk),
4384                                       si->dst_reg, si->src_reg,
4385                                       offsetof(struct bpf_sock_ops_kern, sk));
4386                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4387                                       offsetof(struct sock_common,
4388                                                skc_v6_daddr.s6_addr32[0]) +
4389                                       off);
4390 #else
4391                 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
4392 #endif
4393                 break;
4394 
4395         case offsetof(struct bpf_sock_ops, local_ip6[0]) ...
4396              offsetof(struct bpf_sock_ops, local_ip6[3]):
4397 #if IS_ENABLED(CONFIG_IPV6)
4398                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common,
4399                                           skc_v6_rcv_saddr.s6_addr32[0]) != 4);
4400 
4401                 off = si->off;
4402                 off -= offsetof(struct bpf_sock_ops, local_ip6[0]);
4403                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
4404                                                 struct bpf_sock_ops_kern, sk),
4405                                       si->dst_reg, si->src_reg,
4406                                       offsetof(struct bpf_sock_ops_kern, sk));
4407                 *insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->dst_reg,
4408                                       offsetof(struct sock_common,
4409                                                skc_v6_rcv_saddr.s6_addr32[0]) +
4410                                       off);
4411 #else
4412                 *insn++ = BPF_MOV32_IMM(si->dst_reg, 0);
4413 #endif
4414                 break;
4415 
4416         case offsetof(struct bpf_sock_ops, remote_port):
4417                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_dport) != 2);
4418 
4419                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
4420                                                 struct bpf_sock_ops_kern, sk),
4421                                       si->dst_reg, si->src_reg,
4422                                       offsetof(struct bpf_sock_ops_kern, sk));
4423                 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
4424                                       offsetof(struct sock_common, skc_dport));
4425 #ifndef __BIG_ENDIAN_BITFIELD
4426                 *insn++ = BPF_ALU32_IMM(BPF_LSH, si->dst_reg, 16);
4427 #endif
4428                 break;
4429 
4430         case offsetof(struct bpf_sock_ops, local_port):
4431                 BUILD_BUG_ON(FIELD_SIZEOF(struct sock_common, skc_num) != 2);
4432 
4433                 *insn++ = BPF_LDX_MEM(BPF_FIELD_SIZEOF(
4434                                                 struct bpf_sock_ops_kern, sk),
4435                                       si->dst_reg, si->src_reg,
4436                                       offsetof(struct bpf_sock_ops_kern, sk));
4437                 *insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->dst_reg,
4438                                       offsetof(struct sock_common, skc_num));
4439                 break;
4440         }
4441         return insn - insn_buf;
4442 }
4443 
4444 static u32 sk_skb_convert_ctx_access(enum bpf_access_type type,
4445                                      const struct bpf_insn *si,
4446                                      struct bpf_insn *insn_buf,
4447                                      struct bpf_prog *prog, u32 *target_size)
4448 {
4449         struct bpf_insn *insn = insn_buf;
4450         int off;
4451 
4452         switch (si->off) {
4453         case offsetof(struct __sk_buff, data_end):
4454                 off  = si->off;
4455                 off -= offsetof(struct __sk_buff, data_end);
4456                 off += offsetof(struct sk_buff, cb);
4457                 off += offsetof(struct tcp_skb_cb, bpf.data_end);
4458                 *insn++ = BPF_LDX_MEM(BPF_SIZEOF(void *), si->dst_reg,
4459                                       si->src_reg, off);
4460                 break;
4461         default:
4462                 return bpf_convert_ctx_access(type, si, insn_buf, prog,
4463                                               target_size);
4464         }
4465 
4466         return insn - insn_buf;
4467 }
4468 
4469 const struct bpf_verifier_ops sk_filter_verifier_ops = {
4470         .get_func_proto         = sk_filter_func_proto,
4471         .is_valid_access        = sk_filter_is_valid_access,
4472         .convert_ctx_access     = bpf_convert_ctx_access,
4473 };
4474 
4475 const struct bpf_prog_ops sk_filter_prog_ops = {
4476 };
4477 
4478 const struct bpf_verifier_ops tc_cls_act_verifier_ops = {
4479         .get_func_proto         = tc_cls_act_func_proto,
4480         .is_valid_access        = tc_cls_act_is_valid_access,
4481         .convert_ctx_access     = tc_cls_act_convert_ctx_access,
4482         .gen_prologue           = tc_cls_act_prologue,
4483 };
4484 
4485 const struct bpf_prog_ops tc_cls_act_prog_ops = {
4486         .test_run               = bpf_prog_test_run_skb,
4487 };
4488 
4489 const struct bpf_verifier_ops xdp_verifier_ops = {
4490         .get_func_proto         = xdp_func_proto,
4491         .is_valid_access        = xdp_is_valid_access,
4492         .convert_ctx_access     = xdp_convert_ctx_access,
4493 };
4494 
4495 const struct bpf_prog_ops xdp_prog_ops = {
4496         .test_run               = bpf_prog_test_run_xdp,
4497 };
4498 
4499 const struct bpf_verifier_ops cg_skb_verifier_ops = {
4500         .get_func_proto         = sk_filter_func_proto,
4501         .is_valid_access        = sk_filter_is_valid_access,
4502         .convert_ctx_access     = bpf_convert_ctx_access,
4503 };
4504 
4505 const struct bpf_prog_ops cg_skb_prog_ops = {
4506         .test_run               = bpf_prog_test_run_skb,
4507 };
4508 
4509 const struct bpf_verifier_ops lwt_inout_verifier_ops = {
4510         .get_func_proto         = lwt_inout_func_proto,
4511         .is_valid_access        = lwt_is_valid_access,
4512         .convert_ctx_access     = bpf_convert_ctx_access,
4513 };
4514 
4515 const struct bpf_prog_ops lwt_inout_prog_ops = {
4516         .test_run               = bpf_prog_test_run_skb,
4517 };
4518 
4519 const struct bpf_verifier_ops lwt_xmit_verifier_ops = {
4520         .get_func_proto         = lwt_xmit_func_proto,
4521         .is_valid_access        = lwt_is_valid_access,
4522         .convert_ctx_access     = bpf_convert_ctx_access,
4523         .gen_prologue           = tc_cls_act_prologue,
4524 };
4525 
4526 const struct bpf_prog_ops lwt_xmit_prog_ops = {
4527         .test_run               = bpf_prog_test_run_skb,
4528 };
4529 
4530 const struct bpf_verifier_ops cg_sock_verifier_ops = {
4531         .get_func_proto         = sock_filter_func_proto,
4532         .is_valid_access        = sock_filter_is_valid_access,
4533         .convert_ctx_access     = sock_filter_convert_ctx_access,
4534 };
4535 
4536 const struct bpf_prog_ops cg_sock_prog_ops = {
4537 };
4538 
4539 const struct bpf_verifier_ops sock_ops_verifier_ops = {
4540         .get_func_proto         = sock_ops_func_proto,
4541         .is_valid_access        = sock_ops_is_valid_access,
4542         .convert_ctx_access     = sock_ops_convert_ctx_access,
4543 };
4544 
4545 const struct bpf_prog_ops sock_ops_prog_ops = {
4546 };
4547 
4548 const struct bpf_verifier_ops sk_skb_verifier_ops = {
4549         .get_func_proto         = sk_skb_func_proto,
4550         .is_valid_access        = sk_skb_is_valid_access,
4551         .convert_ctx_access     = sk_skb_convert_ctx_access,
4552         .gen_prologue           = sk_skb_prologue,
4553 };
4554 
4555 const struct bpf_prog_ops sk_skb_prog_ops = {
4556 };
4557 
4558 int sk_detach_filter(struct sock *sk)
4559 {
4560         int ret = -ENOENT;
4561         struct sk_filter *filter;
4562 
4563         if (sock_flag(sk, SOCK_FILTER_LOCKED))
4564                 return -EPERM;
4565 
4566         filter = rcu_dereference_protected(sk->sk_filter,
4567                                            lockdep_sock_is_held(sk));
4568         if (filter) {
4569                 RCU_INIT_POINTER(sk->sk_filter, NULL);
4570                 sk_filter_uncharge(sk, filter);
4571                 ret = 0;
4572         }
4573 
4574         return ret;
4575 }
4576 EXPORT_SYMBOL_GPL(sk_detach_filter);
4577 
4578 int sk_get_filter(struct sock *sk, struct sock_filter __user *ubuf,
4579                   unsigned int len)
4580 {
4581         struct sock_fprog_kern *fprog;
4582         struct sk_filter *filter;
4583         int ret = 0;
4584 
4585         lock_sock(sk);
4586         filter = rcu_dereference_protected(sk->sk_filter,
4587                                            lockdep_sock_is_held(sk));
4588         if (!filter)
4589                 goto out;
4590 
4591         /* We're copying the filter that has been originally attached,
4592          * so no conversion/decode needed anymore. eBPF programs that
4593          * have no original program cannot be dumped through this.
4594          */
4595         ret = -EACCES;
4596         fprog = filter->prog->orig_prog;
4597         if (!fprog)
4598                 goto out;
4599 
4600         ret = fprog->len;
4601         if (!len)
4602                 /* User space only enquires number of filter blocks. */
4603                 goto out;
4604 
4605         ret = -EINVAL;
4606         if (len < fprog->len)
4607                 goto out;
4608 
4609         ret = -EFAULT;
4610         if (copy_to_user(ubuf, fprog->filter, bpf_classic_proglen(fprog)))
4611                 goto out;
4612 
4613         /* Instead of bytes, the API requests to return the number
4614          * of filter blocks.
4615          */
4616         ret = fprog->len;
4617 out:
4618         release_sock(sk);
4619         return ret;
4620 }
4621 

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