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TOMOYO Linux Cross Reference
Linux/kernel/bpf/core.c

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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/filter.h>
 25 #include <linux/skbuff.h>
 26 #include <linux/vmalloc.h>
 27 #include <linux/random.h>
 28 #include <linux/moduleloader.h>
 29 #include <linux/bpf.h>
 30 #include <linux/frame.h>
 31 #include <linux/rbtree_latch.h>
 32 #include <linux/kallsyms.h>
 33 #include <linux/rcupdate.h>
 34 #include <linux/perf_event.h>
 35 
 36 #include <asm/unaligned.h>
 37 
 38 /* Registers */
 39 #define BPF_R0  regs[BPF_REG_0]
 40 #define BPF_R1  regs[BPF_REG_1]
 41 #define BPF_R2  regs[BPF_REG_2]
 42 #define BPF_R3  regs[BPF_REG_3]
 43 #define BPF_R4  regs[BPF_REG_4]
 44 #define BPF_R5  regs[BPF_REG_5]
 45 #define BPF_R6  regs[BPF_REG_6]
 46 #define BPF_R7  regs[BPF_REG_7]
 47 #define BPF_R8  regs[BPF_REG_8]
 48 #define BPF_R9  regs[BPF_REG_9]
 49 #define BPF_R10 regs[BPF_REG_10]
 50 
 51 /* Named registers */
 52 #define DST     regs[insn->dst_reg]
 53 #define SRC     regs[insn->src_reg]
 54 #define FP      regs[BPF_REG_FP]
 55 #define ARG1    regs[BPF_REG_ARG1]
 56 #define CTX     regs[BPF_REG_CTX]
 57 #define IMM     insn->imm
 58 
 59 /* No hurry in this branch
 60  *
 61  * Exported for the bpf jit load helper.
 62  */
 63 void *bpf_internal_load_pointer_neg_helper(const struct sk_buff *skb, int k, unsigned int size)
 64 {
 65         u8 *ptr = NULL;
 66 
 67         if (k >= SKF_NET_OFF)
 68                 ptr = skb_network_header(skb) + k - SKF_NET_OFF;
 69         else if (k >= SKF_LL_OFF)
 70                 ptr = skb_mac_header(skb) + k - SKF_LL_OFF;
 71 
 72         if (ptr >= skb->head && ptr + size <= skb_tail_pointer(skb))
 73                 return ptr;
 74 
 75         return NULL;
 76 }
 77 
 78 struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags)
 79 {
 80         gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | gfp_extra_flags;
 81         struct bpf_prog_aux *aux;
 82         struct bpf_prog *fp;
 83 
 84         size = round_up(size, PAGE_SIZE);
 85         fp = __vmalloc(size, gfp_flags, PAGE_KERNEL);
 86         if (fp == NULL)
 87                 return NULL;
 88 
 89         aux = kzalloc(sizeof(*aux), GFP_KERNEL | gfp_extra_flags);
 90         if (aux == NULL) {
 91                 vfree(fp);
 92                 return NULL;
 93         }
 94 
 95         fp->pages = size / PAGE_SIZE;
 96         fp->aux = aux;
 97         fp->aux->prog = fp;
 98         fp->jit_requested = ebpf_jit_enabled();
 99 
100         INIT_LIST_HEAD_RCU(&fp->aux->ksym_lnode);
101 
102         return fp;
103 }
104 EXPORT_SYMBOL_GPL(bpf_prog_alloc);
105 
106 struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size,
107                                   gfp_t gfp_extra_flags)
108 {
109         gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | gfp_extra_flags;
110         struct bpf_prog *fp;
111         u32 pages, delta;
112         int ret;
113 
114         BUG_ON(fp_old == NULL);
115 
116         size = round_up(size, PAGE_SIZE);
117         pages = size / PAGE_SIZE;
118         if (pages <= fp_old->pages)
119                 return fp_old;
120 
121         delta = pages - fp_old->pages;
122         ret = __bpf_prog_charge(fp_old->aux->user, delta);
123         if (ret)
124                 return NULL;
125 
126         fp = __vmalloc(size, gfp_flags, PAGE_KERNEL);
127         if (fp == NULL) {
128                 __bpf_prog_uncharge(fp_old->aux->user, delta);
129         } else {
130                 memcpy(fp, fp_old, fp_old->pages * PAGE_SIZE);
131                 fp->pages = pages;
132                 fp->aux->prog = fp;
133 
134                 /* We keep fp->aux from fp_old around in the new
135                  * reallocated structure.
136                  */
137                 fp_old->aux = NULL;
138                 __bpf_prog_free(fp_old);
139         }
140 
141         return fp;
142 }
143 
144 void __bpf_prog_free(struct bpf_prog *fp)
145 {
146         kfree(fp->aux);
147         vfree(fp);
148 }
149 
150 int bpf_prog_calc_tag(struct bpf_prog *fp)
151 {
152         const u32 bits_offset = SHA_MESSAGE_BYTES - sizeof(__be64);
153         u32 raw_size = bpf_prog_tag_scratch_size(fp);
154         u32 digest[SHA_DIGEST_WORDS];
155         u32 ws[SHA_WORKSPACE_WORDS];
156         u32 i, bsize, psize, blocks;
157         struct bpf_insn *dst;
158         bool was_ld_map;
159         u8 *raw, *todo;
160         __be32 *result;
161         __be64 *bits;
162 
163         raw = vmalloc(raw_size);
164         if (!raw)
165                 return -ENOMEM;
166 
167         sha_init(digest);
168         memset(ws, 0, sizeof(ws));
169 
170         /* We need to take out the map fd for the digest calculation
171          * since they are unstable from user space side.
172          */
173         dst = (void *)raw;
174         for (i = 0, was_ld_map = false; i < fp->len; i++) {
175                 dst[i] = fp->insnsi[i];
176                 if (!was_ld_map &&
177                     dst[i].code == (BPF_LD | BPF_IMM | BPF_DW) &&
178                     dst[i].src_reg == BPF_PSEUDO_MAP_FD) {
179                         was_ld_map = true;
180                         dst[i].imm = 0;
181                 } else if (was_ld_map &&
182                            dst[i].code == 0 &&
183                            dst[i].dst_reg == 0 &&
184                            dst[i].src_reg == 0 &&
185                            dst[i].off == 0) {
186                         was_ld_map = false;
187                         dst[i].imm = 0;
188                 } else {
189                         was_ld_map = false;
190                 }
191         }
192 
193         psize = bpf_prog_insn_size(fp);
194         memset(&raw[psize], 0, raw_size - psize);
195         raw[psize++] = 0x80;
196 
197         bsize  = round_up(psize, SHA_MESSAGE_BYTES);
198         blocks = bsize / SHA_MESSAGE_BYTES;
199         todo   = raw;
200         if (bsize - psize >= sizeof(__be64)) {
201                 bits = (__be64 *)(todo + bsize - sizeof(__be64));
202         } else {
203                 bits = (__be64 *)(todo + bsize + bits_offset);
204                 blocks++;
205         }
206         *bits = cpu_to_be64((psize - 1) << 3);
207 
208         while (blocks--) {
209                 sha_transform(digest, todo, ws);
210                 todo += SHA_MESSAGE_BYTES;
211         }
212 
213         result = (__force __be32 *)digest;
214         for (i = 0; i < SHA_DIGEST_WORDS; i++)
215                 result[i] = cpu_to_be32(digest[i]);
216         memcpy(fp->tag, result, sizeof(fp->tag));
217 
218         vfree(raw);
219         return 0;
220 }
221 
222 static int bpf_adj_delta_to_imm(struct bpf_insn *insn, u32 pos, u32 delta,
223                                 u32 curr, const bool probe_pass)
224 {
225         const s64 imm_min = S32_MIN, imm_max = S32_MAX;
226         s64 imm = insn->imm;
227 
228         if (curr < pos && curr + imm + 1 > pos)
229                 imm += delta;
230         else if (curr > pos + delta && curr + imm + 1 <= pos + delta)
231                 imm -= delta;
232         if (imm < imm_min || imm > imm_max)
233                 return -ERANGE;
234         if (!probe_pass)
235                 insn->imm = imm;
236         return 0;
237 }
238 
239 static int bpf_adj_delta_to_off(struct bpf_insn *insn, u32 pos, u32 delta,
240                                 u32 curr, const bool probe_pass)
241 {
242         const s32 off_min = S16_MIN, off_max = S16_MAX;
243         s32 off = insn->off;
244 
245         if (curr < pos && curr + off + 1 > pos)
246                 off += delta;
247         else if (curr > pos + delta && curr + off + 1 <= pos + delta)
248                 off -= delta;
249         if (off < off_min || off > off_max)
250                 return -ERANGE;
251         if (!probe_pass)
252                 insn->off = off;
253         return 0;
254 }
255 
256 static int bpf_adj_branches(struct bpf_prog *prog, u32 pos, u32 delta,
257                             const bool probe_pass)
258 {
259         u32 i, insn_cnt = prog->len + (probe_pass ? delta : 0);
260         struct bpf_insn *insn = prog->insnsi;
261         int ret = 0;
262 
263         for (i = 0; i < insn_cnt; i++, insn++) {
264                 u8 code;
265 
266                 /* In the probing pass we still operate on the original,
267                  * unpatched image in order to check overflows before we
268                  * do any other adjustments. Therefore skip the patchlet.
269                  */
270                 if (probe_pass && i == pos) {
271                         i += delta + 1;
272                         insn++;
273                 }
274                 code = insn->code;
275                 if (BPF_CLASS(code) != BPF_JMP ||
276                     BPF_OP(code) == BPF_EXIT)
277                         continue;
278                 /* Adjust offset of jmps if we cross patch boundaries. */
279                 if (BPF_OP(code) == BPF_CALL) {
280                         if (insn->src_reg != BPF_PSEUDO_CALL)
281                                 continue;
282                         ret = bpf_adj_delta_to_imm(insn, pos, delta, i,
283                                                    probe_pass);
284                 } else {
285                         ret = bpf_adj_delta_to_off(insn, pos, delta, i,
286                                                    probe_pass);
287                 }
288                 if (ret)
289                         break;
290         }
291 
292         return ret;
293 }
294 
295 struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off,
296                                        const struct bpf_insn *patch, u32 len)
297 {
298         u32 insn_adj_cnt, insn_rest, insn_delta = len - 1;
299         const u32 cnt_max = S16_MAX;
300         struct bpf_prog *prog_adj;
301 
302         /* Since our patchlet doesn't expand the image, we're done. */
303         if (insn_delta == 0) {
304                 memcpy(prog->insnsi + off, patch, sizeof(*patch));
305                 return prog;
306         }
307 
308         insn_adj_cnt = prog->len + insn_delta;
309 
310         /* Reject anything that would potentially let the insn->off
311          * target overflow when we have excessive program expansions.
312          * We need to probe here before we do any reallocation where
313          * we afterwards may not fail anymore.
314          */
315         if (insn_adj_cnt > cnt_max &&
316             bpf_adj_branches(prog, off, insn_delta, true))
317                 return NULL;
318 
319         /* Several new instructions need to be inserted. Make room
320          * for them. Likely, there's no need for a new allocation as
321          * last page could have large enough tailroom.
322          */
323         prog_adj = bpf_prog_realloc(prog, bpf_prog_size(insn_adj_cnt),
324                                     GFP_USER);
325         if (!prog_adj)
326                 return NULL;
327 
328         prog_adj->len = insn_adj_cnt;
329 
330         /* Patching happens in 3 steps:
331          *
332          * 1) Move over tail of insnsi from next instruction onwards,
333          *    so we can patch the single target insn with one or more
334          *    new ones (patching is always from 1 to n insns, n > 0).
335          * 2) Inject new instructions at the target location.
336          * 3) Adjust branch offsets if necessary.
337          */
338         insn_rest = insn_adj_cnt - off - len;
339 
340         memmove(prog_adj->insnsi + off + len, prog_adj->insnsi + off + 1,
341                 sizeof(*patch) * insn_rest);
342         memcpy(prog_adj->insnsi + off, patch, sizeof(*patch) * len);
343 
344         /* We are guaranteed to not fail at this point, otherwise
345          * the ship has sailed to reverse to the original state. An
346          * overflow cannot happen at this point.
347          */
348         BUG_ON(bpf_adj_branches(prog_adj, off, insn_delta, false));
349 
350         return prog_adj;
351 }
352 
353 void bpf_prog_kallsyms_del_subprogs(struct bpf_prog *fp)
354 {
355         int i;
356 
357         for (i = 0; i < fp->aux->func_cnt; i++)
358                 bpf_prog_kallsyms_del(fp->aux->func[i]);
359 }
360 
361 void bpf_prog_kallsyms_del_all(struct bpf_prog *fp)
362 {
363         bpf_prog_kallsyms_del_subprogs(fp);
364         bpf_prog_kallsyms_del(fp);
365 }
366 
367 #ifdef CONFIG_BPF_JIT
368 # define BPF_JIT_LIMIT_DEFAULT  (PAGE_SIZE * 40000)
369 
370 /* All BPF JIT sysctl knobs here. */
371 int bpf_jit_enable   __read_mostly = IS_BUILTIN(CONFIG_BPF_JIT_ALWAYS_ON);
372 int bpf_jit_harden   __read_mostly;
373 int bpf_jit_kallsyms __read_mostly;
374 int bpf_jit_limit    __read_mostly = BPF_JIT_LIMIT_DEFAULT;
375 
376 static __always_inline void
377 bpf_get_prog_addr_region(const struct bpf_prog *prog,
378                          unsigned long *symbol_start,
379                          unsigned long *symbol_end)
380 {
381         const struct bpf_binary_header *hdr = bpf_jit_binary_hdr(prog);
382         unsigned long addr = (unsigned long)hdr;
383 
384         WARN_ON_ONCE(!bpf_prog_ebpf_jited(prog));
385 
386         *symbol_start = addr;
387         *symbol_end   = addr + hdr->pages * PAGE_SIZE;
388 }
389 
390 static void bpf_get_prog_name(const struct bpf_prog *prog, char *sym)
391 {
392         const char *end = sym + KSYM_NAME_LEN;
393 
394         BUILD_BUG_ON(sizeof("bpf_prog_") +
395                      sizeof(prog->tag) * 2 +
396                      /* name has been null terminated.
397                       * We should need +1 for the '_' preceding
398                       * the name.  However, the null character
399                       * is double counted between the name and the
400                       * sizeof("bpf_prog_") above, so we omit
401                       * the +1 here.
402                       */
403                      sizeof(prog->aux->name) > KSYM_NAME_LEN);
404 
405         sym += snprintf(sym, KSYM_NAME_LEN, "bpf_prog_");
406         sym  = bin2hex(sym, prog->tag, sizeof(prog->tag));
407         if (prog->aux->name[0])
408                 snprintf(sym, (size_t)(end - sym), "_%s", prog->aux->name);
409         else
410                 *sym = 0;
411 }
412 
413 static __always_inline unsigned long
414 bpf_get_prog_addr_start(struct latch_tree_node *n)
415 {
416         unsigned long symbol_start, symbol_end;
417         const struct bpf_prog_aux *aux;
418 
419         aux = container_of(n, struct bpf_prog_aux, ksym_tnode);
420         bpf_get_prog_addr_region(aux->prog, &symbol_start, &symbol_end);
421 
422         return symbol_start;
423 }
424 
425 static __always_inline bool bpf_tree_less(struct latch_tree_node *a,
426                                           struct latch_tree_node *b)
427 {
428         return bpf_get_prog_addr_start(a) < bpf_get_prog_addr_start(b);
429 }
430 
431 static __always_inline int bpf_tree_comp(void *key, struct latch_tree_node *n)
432 {
433         unsigned long val = (unsigned long)key;
434         unsigned long symbol_start, symbol_end;
435         const struct bpf_prog_aux *aux;
436 
437         aux = container_of(n, struct bpf_prog_aux, ksym_tnode);
438         bpf_get_prog_addr_region(aux->prog, &symbol_start, &symbol_end);
439 
440         if (val < symbol_start)
441                 return -1;
442         if (val >= symbol_end)
443                 return  1;
444 
445         return 0;
446 }
447 
448 static const struct latch_tree_ops bpf_tree_ops = {
449         .less   = bpf_tree_less,
450         .comp   = bpf_tree_comp,
451 };
452 
453 static DEFINE_SPINLOCK(bpf_lock);
454 static LIST_HEAD(bpf_kallsyms);
455 static struct latch_tree_root bpf_tree __cacheline_aligned;
456 
457 static void bpf_prog_ksym_node_add(struct bpf_prog_aux *aux)
458 {
459         WARN_ON_ONCE(!list_empty(&aux->ksym_lnode));
460         list_add_tail_rcu(&aux->ksym_lnode, &bpf_kallsyms);
461         latch_tree_insert(&aux->ksym_tnode, &bpf_tree, &bpf_tree_ops);
462 }
463 
464 static void bpf_prog_ksym_node_del(struct bpf_prog_aux *aux)
465 {
466         if (list_empty(&aux->ksym_lnode))
467                 return;
468 
469         latch_tree_erase(&aux->ksym_tnode, &bpf_tree, &bpf_tree_ops);
470         list_del_rcu(&aux->ksym_lnode);
471 }
472 
473 static bool bpf_prog_kallsyms_candidate(const struct bpf_prog *fp)
474 {
475         return fp->jited && !bpf_prog_was_classic(fp);
476 }
477 
478 static bool bpf_prog_kallsyms_verify_off(const struct bpf_prog *fp)
479 {
480         return list_empty(&fp->aux->ksym_lnode) ||
481                fp->aux->ksym_lnode.prev == LIST_POISON2;
482 }
483 
484 void bpf_prog_kallsyms_add(struct bpf_prog *fp)
485 {
486         if (!bpf_prog_kallsyms_candidate(fp) ||
487             !capable(CAP_SYS_ADMIN))
488                 return;
489 
490         spin_lock_bh(&bpf_lock);
491         bpf_prog_ksym_node_add(fp->aux);
492         spin_unlock_bh(&bpf_lock);
493 }
494 
495 void bpf_prog_kallsyms_del(struct bpf_prog *fp)
496 {
497         if (!bpf_prog_kallsyms_candidate(fp))
498                 return;
499 
500         spin_lock_bh(&bpf_lock);
501         bpf_prog_ksym_node_del(fp->aux);
502         spin_unlock_bh(&bpf_lock);
503 }
504 
505 static struct bpf_prog *bpf_prog_kallsyms_find(unsigned long addr)
506 {
507         struct latch_tree_node *n;
508 
509         if (!bpf_jit_kallsyms_enabled())
510                 return NULL;
511 
512         n = latch_tree_find((void *)addr, &bpf_tree, &bpf_tree_ops);
513         return n ?
514                container_of(n, struct bpf_prog_aux, ksym_tnode)->prog :
515                NULL;
516 }
517 
518 const char *__bpf_address_lookup(unsigned long addr, unsigned long *size,
519                                  unsigned long *off, char *sym)
520 {
521         unsigned long symbol_start, symbol_end;
522         struct bpf_prog *prog;
523         char *ret = NULL;
524 
525         rcu_read_lock();
526         prog = bpf_prog_kallsyms_find(addr);
527         if (prog) {
528                 bpf_get_prog_addr_region(prog, &symbol_start, &symbol_end);
529                 bpf_get_prog_name(prog, sym);
530 
531                 ret = sym;
532                 if (size)
533                         *size = symbol_end - symbol_start;
534                 if (off)
535                         *off  = addr - symbol_start;
536         }
537         rcu_read_unlock();
538 
539         return ret;
540 }
541 
542 bool is_bpf_text_address(unsigned long addr)
543 {
544         bool ret;
545 
546         rcu_read_lock();
547         ret = bpf_prog_kallsyms_find(addr) != NULL;
548         rcu_read_unlock();
549 
550         return ret;
551 }
552 
553 int bpf_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
554                     char *sym)
555 {
556         struct bpf_prog_aux *aux;
557         unsigned int it = 0;
558         int ret = -ERANGE;
559 
560         if (!bpf_jit_kallsyms_enabled())
561                 return ret;
562 
563         rcu_read_lock();
564         list_for_each_entry_rcu(aux, &bpf_kallsyms, ksym_lnode) {
565                 if (it++ != symnum)
566                         continue;
567 
568                 bpf_get_prog_name(aux->prog, sym);
569 
570                 *value = (unsigned long)aux->prog->bpf_func;
571                 *type  = BPF_SYM_ELF_TYPE;
572 
573                 ret = 0;
574                 break;
575         }
576         rcu_read_unlock();
577 
578         return ret;
579 }
580 
581 static atomic_long_t bpf_jit_current;
582 
583 #if defined(MODULES_VADDR)
584 static int __init bpf_jit_charge_init(void)
585 {
586         /* Only used as heuristic here to derive limit. */
587         bpf_jit_limit = min_t(u64, round_up((MODULES_END - MODULES_VADDR) >> 2,
588                                             PAGE_SIZE), INT_MAX);
589         return 0;
590 }
591 pure_initcall(bpf_jit_charge_init);
592 #endif
593 
594 static int bpf_jit_charge_modmem(u32 pages)
595 {
596         if (atomic_long_add_return(pages, &bpf_jit_current) >
597             (bpf_jit_limit >> PAGE_SHIFT)) {
598                 if (!capable(CAP_SYS_ADMIN)) {
599                         atomic_long_sub(pages, &bpf_jit_current);
600                         return -EPERM;
601                 }
602         }
603 
604         return 0;
605 }
606 
607 static void bpf_jit_uncharge_modmem(u32 pages)
608 {
609         atomic_long_sub(pages, &bpf_jit_current);
610 }
611 
612 struct bpf_binary_header *
613 bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr,
614                      unsigned int alignment,
615                      bpf_jit_fill_hole_t bpf_fill_ill_insns)
616 {
617         struct bpf_binary_header *hdr;
618         u32 size, hole, start, pages;
619 
620         /* Most of BPF filters are really small, but if some of them
621          * fill a page, allow at least 128 extra bytes to insert a
622          * random section of illegal instructions.
623          */
624         size = round_up(proglen + sizeof(*hdr) + 128, PAGE_SIZE);
625         pages = size / PAGE_SIZE;
626 
627         if (bpf_jit_charge_modmem(pages))
628                 return NULL;
629         hdr = module_alloc(size);
630         if (!hdr) {
631                 bpf_jit_uncharge_modmem(pages);
632                 return NULL;
633         }
634 
635         /* Fill space with illegal/arch-dep instructions. */
636         bpf_fill_ill_insns(hdr, size);
637 
638         hdr->pages = pages;
639         hole = min_t(unsigned int, size - (proglen + sizeof(*hdr)),
640                      PAGE_SIZE - sizeof(*hdr));
641         start = (get_random_int() % hole) & ~(alignment - 1);
642 
643         /* Leave a random number of instructions before BPF code. */
644         *image_ptr = &hdr->image[start];
645 
646         return hdr;
647 }
648 
649 void bpf_jit_binary_free(struct bpf_binary_header *hdr)
650 {
651         u32 pages = hdr->pages;
652 
653         module_memfree(hdr);
654         bpf_jit_uncharge_modmem(pages);
655 }
656 
657 /* This symbol is only overridden by archs that have different
658  * requirements than the usual eBPF JITs, f.e. when they only
659  * implement cBPF JIT, do not set images read-only, etc.
660  */
661 void __weak bpf_jit_free(struct bpf_prog *fp)
662 {
663         if (fp->jited) {
664                 struct bpf_binary_header *hdr = bpf_jit_binary_hdr(fp);
665 
666                 bpf_jit_binary_unlock_ro(hdr);
667                 bpf_jit_binary_free(hdr);
668 
669                 WARN_ON_ONCE(!bpf_prog_kallsyms_verify_off(fp));
670         }
671 
672         bpf_prog_unlock_free(fp);
673 }
674 
675 static int bpf_jit_blind_insn(const struct bpf_insn *from,
676                               const struct bpf_insn *aux,
677                               struct bpf_insn *to_buff)
678 {
679         struct bpf_insn *to = to_buff;
680         u32 imm_rnd = get_random_int();
681         s16 off;
682 
683         BUILD_BUG_ON(BPF_REG_AX  + 1 != MAX_BPF_JIT_REG);
684         BUILD_BUG_ON(MAX_BPF_REG + 1 != MAX_BPF_JIT_REG);
685 
686         if (from->imm == 0 &&
687             (from->code == (BPF_ALU   | BPF_MOV | BPF_K) ||
688              from->code == (BPF_ALU64 | BPF_MOV | BPF_K))) {
689                 *to++ = BPF_ALU64_REG(BPF_XOR, from->dst_reg, from->dst_reg);
690                 goto out;
691         }
692 
693         switch (from->code) {
694         case BPF_ALU | BPF_ADD | BPF_K:
695         case BPF_ALU | BPF_SUB | BPF_K:
696         case BPF_ALU | BPF_AND | BPF_K:
697         case BPF_ALU | BPF_OR  | BPF_K:
698         case BPF_ALU | BPF_XOR | BPF_K:
699         case BPF_ALU | BPF_MUL | BPF_K:
700         case BPF_ALU | BPF_MOV | BPF_K:
701         case BPF_ALU | BPF_DIV | BPF_K:
702         case BPF_ALU | BPF_MOD | BPF_K:
703                 *to++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm);
704                 *to++ = BPF_ALU32_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
705                 *to++ = BPF_ALU32_REG(from->code, from->dst_reg, BPF_REG_AX);
706                 break;
707 
708         case BPF_ALU64 | BPF_ADD | BPF_K:
709         case BPF_ALU64 | BPF_SUB | BPF_K:
710         case BPF_ALU64 | BPF_AND | BPF_K:
711         case BPF_ALU64 | BPF_OR  | BPF_K:
712         case BPF_ALU64 | BPF_XOR | BPF_K:
713         case BPF_ALU64 | BPF_MUL | BPF_K:
714         case BPF_ALU64 | BPF_MOV | BPF_K:
715         case BPF_ALU64 | BPF_DIV | BPF_K:
716         case BPF_ALU64 | BPF_MOD | BPF_K:
717                 *to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm);
718                 *to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
719                 *to++ = BPF_ALU64_REG(from->code, from->dst_reg, BPF_REG_AX);
720                 break;
721 
722         case BPF_JMP | BPF_JEQ  | BPF_K:
723         case BPF_JMP | BPF_JNE  | BPF_K:
724         case BPF_JMP | BPF_JGT  | BPF_K:
725         case BPF_JMP | BPF_JLT  | BPF_K:
726         case BPF_JMP | BPF_JGE  | BPF_K:
727         case BPF_JMP | BPF_JLE  | BPF_K:
728         case BPF_JMP | BPF_JSGT | BPF_K:
729         case BPF_JMP | BPF_JSLT | BPF_K:
730         case BPF_JMP | BPF_JSGE | BPF_K:
731         case BPF_JMP | BPF_JSLE | BPF_K:
732         case BPF_JMP | BPF_JSET | BPF_K:
733                 /* Accommodate for extra offset in case of a backjump. */
734                 off = from->off;
735                 if (off < 0)
736                         off -= 2;
737                 *to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm);
738                 *to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
739                 *to++ = BPF_JMP_REG(from->code, from->dst_reg, BPF_REG_AX, off);
740                 break;
741 
742         case BPF_LD | BPF_IMM | BPF_DW:
743                 *to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ aux[1].imm);
744                 *to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
745                 *to++ = BPF_ALU64_IMM(BPF_LSH, BPF_REG_AX, 32);
746                 *to++ = BPF_ALU64_REG(BPF_MOV, aux[0].dst_reg, BPF_REG_AX);
747                 break;
748         case 0: /* Part 2 of BPF_LD | BPF_IMM | BPF_DW. */
749                 *to++ = BPF_ALU32_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ aux[0].imm);
750                 *to++ = BPF_ALU32_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
751                 *to++ = BPF_ALU64_REG(BPF_OR,  aux[0].dst_reg, BPF_REG_AX);
752                 break;
753 
754         case BPF_ST | BPF_MEM | BPF_DW:
755         case BPF_ST | BPF_MEM | BPF_W:
756         case BPF_ST | BPF_MEM | BPF_H:
757         case BPF_ST | BPF_MEM | BPF_B:
758                 *to++ = BPF_ALU64_IMM(BPF_MOV, BPF_REG_AX, imm_rnd ^ from->imm);
759                 *to++ = BPF_ALU64_IMM(BPF_XOR, BPF_REG_AX, imm_rnd);
760                 *to++ = BPF_STX_MEM(from->code, from->dst_reg, BPF_REG_AX, from->off);
761                 break;
762         }
763 out:
764         return to - to_buff;
765 }
766 
767 static struct bpf_prog *bpf_prog_clone_create(struct bpf_prog *fp_other,
768                                               gfp_t gfp_extra_flags)
769 {
770         gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | gfp_extra_flags;
771         struct bpf_prog *fp;
772 
773         fp = __vmalloc(fp_other->pages * PAGE_SIZE, gfp_flags, PAGE_KERNEL);
774         if (fp != NULL) {
775                 /* aux->prog still points to the fp_other one, so
776                  * when promoting the clone to the real program,
777                  * this still needs to be adapted.
778                  */
779                 memcpy(fp, fp_other, fp_other->pages * PAGE_SIZE);
780         }
781 
782         return fp;
783 }
784 
785 static void bpf_prog_clone_free(struct bpf_prog *fp)
786 {
787         /* aux was stolen by the other clone, so we cannot free
788          * it from this path! It will be freed eventually by the
789          * other program on release.
790          *
791          * At this point, we don't need a deferred release since
792          * clone is guaranteed to not be locked.
793          */
794         fp->aux = NULL;
795         __bpf_prog_free(fp);
796 }
797 
798 void bpf_jit_prog_release_other(struct bpf_prog *fp, struct bpf_prog *fp_other)
799 {
800         /* We have to repoint aux->prog to self, as we don't
801          * know whether fp here is the clone or the original.
802          */
803         fp->aux->prog = fp;
804         bpf_prog_clone_free(fp_other);
805 }
806 
807 struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *prog)
808 {
809         struct bpf_insn insn_buff[16], aux[2];
810         struct bpf_prog *clone, *tmp;
811         int insn_delta, insn_cnt;
812         struct bpf_insn *insn;
813         int i, rewritten;
814 
815         if (!bpf_jit_blinding_enabled(prog) || prog->blinded)
816                 return prog;
817 
818         clone = bpf_prog_clone_create(prog, GFP_USER);
819         if (!clone)
820                 return ERR_PTR(-ENOMEM);
821 
822         insn_cnt = clone->len;
823         insn = clone->insnsi;
824 
825         for (i = 0; i < insn_cnt; i++, insn++) {
826                 /* We temporarily need to hold the original ld64 insn
827                  * so that we can still access the first part in the
828                  * second blinding run.
829                  */
830                 if (insn[0].code == (BPF_LD | BPF_IMM | BPF_DW) &&
831                     insn[1].code == 0)
832                         memcpy(aux, insn, sizeof(aux));
833 
834                 rewritten = bpf_jit_blind_insn(insn, aux, insn_buff);
835                 if (!rewritten)
836                         continue;
837 
838                 tmp = bpf_patch_insn_single(clone, i, insn_buff, rewritten);
839                 if (!tmp) {
840                         /* Patching may have repointed aux->prog during
841                          * realloc from the original one, so we need to
842                          * fix it up here on error.
843                          */
844                         bpf_jit_prog_release_other(prog, clone);
845                         return ERR_PTR(-ENOMEM);
846                 }
847 
848                 clone = tmp;
849                 insn_delta = rewritten - 1;
850 
851                 /* Walk new program and skip insns we just inserted. */
852                 insn = clone->insnsi + i + insn_delta;
853                 insn_cnt += insn_delta;
854                 i        += insn_delta;
855         }
856 
857         clone->blinded = 1;
858         return clone;
859 }
860 #endif /* CONFIG_BPF_JIT */
861 
862 /* Base function for offset calculation. Needs to go into .text section,
863  * therefore keeping it non-static as well; will also be used by JITs
864  * anyway later on, so do not let the compiler omit it. This also needs
865  * to go into kallsyms for correlation from e.g. bpftool, so naming
866  * must not change.
867  */
868 noinline u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
869 {
870         return 0;
871 }
872 EXPORT_SYMBOL_GPL(__bpf_call_base);
873 
874 /* All UAPI available opcodes. */
875 #define BPF_INSN_MAP(INSN_2, INSN_3)            \
876         /* 32 bit ALU operations. */            \
877         /*   Register based. */                 \
878         INSN_3(ALU, ADD, X),                    \
879         INSN_3(ALU, SUB, X),                    \
880         INSN_3(ALU, AND, X),                    \
881         INSN_3(ALU, OR,  X),                    \
882         INSN_3(ALU, LSH, X),                    \
883         INSN_3(ALU, RSH, X),                    \
884         INSN_3(ALU, XOR, X),                    \
885         INSN_3(ALU, MUL, X),                    \
886         INSN_3(ALU, MOV, X),                    \
887         INSN_3(ALU, DIV, X),                    \
888         INSN_3(ALU, MOD, X),                    \
889         INSN_2(ALU, NEG),                       \
890         INSN_3(ALU, END, TO_BE),                \
891         INSN_3(ALU, END, TO_LE),                \
892         /*   Immediate based. */                \
893         INSN_3(ALU, ADD, K),                    \
894         INSN_3(ALU, SUB, K),                    \
895         INSN_3(ALU, AND, K),                    \
896         INSN_3(ALU, OR,  K),                    \
897         INSN_3(ALU, LSH, K),                    \
898         INSN_3(ALU, RSH, K),                    \
899         INSN_3(ALU, XOR, K),                    \
900         INSN_3(ALU, MUL, K),                    \
901         INSN_3(ALU, MOV, K),                    \
902         INSN_3(ALU, DIV, K),                    \
903         INSN_3(ALU, MOD, K),                    \
904         /* 64 bit ALU operations. */            \
905         /*   Register based. */                 \
906         INSN_3(ALU64, ADD,  X),                 \
907         INSN_3(ALU64, SUB,  X),                 \
908         INSN_3(ALU64, AND,  X),                 \
909         INSN_3(ALU64, OR,   X),                 \
910         INSN_3(ALU64, LSH,  X),                 \
911         INSN_3(ALU64, RSH,  X),                 \
912         INSN_3(ALU64, XOR,  X),                 \
913         INSN_3(ALU64, MUL,  X),                 \
914         INSN_3(ALU64, MOV,  X),                 \
915         INSN_3(ALU64, ARSH, X),                 \
916         INSN_3(ALU64, DIV,  X),                 \
917         INSN_3(ALU64, MOD,  X),                 \
918         INSN_2(ALU64, NEG),                     \
919         /*   Immediate based. */                \
920         INSN_3(ALU64, ADD,  K),                 \
921         INSN_3(ALU64, SUB,  K),                 \
922         INSN_3(ALU64, AND,  K),                 \
923         INSN_3(ALU64, OR,   K),                 \
924         INSN_3(ALU64, LSH,  K),                 \
925         INSN_3(ALU64, RSH,  K),                 \
926         INSN_3(ALU64, XOR,  K),                 \
927         INSN_3(ALU64, MUL,  K),                 \
928         INSN_3(ALU64, MOV,  K),                 \
929         INSN_3(ALU64, ARSH, K),                 \
930         INSN_3(ALU64, DIV,  K),                 \
931         INSN_3(ALU64, MOD,  K),                 \
932         /* Call instruction. */                 \
933         INSN_2(JMP, CALL),                      \
934         /* Exit instruction. */                 \
935         INSN_2(JMP, EXIT),                      \
936         /* Jump instructions. */                \
937         /*   Register based. */                 \
938         INSN_3(JMP, JEQ,  X),                   \
939         INSN_3(JMP, JNE,  X),                   \
940         INSN_3(JMP, JGT,  X),                   \
941         INSN_3(JMP, JLT,  X),                   \
942         INSN_3(JMP, JGE,  X),                   \
943         INSN_3(JMP, JLE,  X),                   \
944         INSN_3(JMP, JSGT, X),                   \
945         INSN_3(JMP, JSLT, X),                   \
946         INSN_3(JMP, JSGE, X),                   \
947         INSN_3(JMP, JSLE, X),                   \
948         INSN_3(JMP, JSET, X),                   \
949         /*   Immediate based. */                \
950         INSN_3(JMP, JEQ,  K),                   \
951         INSN_3(JMP, JNE,  K),                   \
952         INSN_3(JMP, JGT,  K),                   \
953         INSN_3(JMP, JLT,  K),                   \
954         INSN_3(JMP, JGE,  K),                   \
955         INSN_3(JMP, JLE,  K),                   \
956         INSN_3(JMP, JSGT, K),                   \
957         INSN_3(JMP, JSLT, K),                   \
958         INSN_3(JMP, JSGE, K),                   \
959         INSN_3(JMP, JSLE, K),                   \
960         INSN_3(JMP, JSET, K),                   \
961         INSN_2(JMP, JA),                        \
962         /* Store instructions. */               \
963         /*   Register based. */                 \
964         INSN_3(STX, MEM,  B),                   \
965         INSN_3(STX, MEM,  H),                   \
966         INSN_3(STX, MEM,  W),                   \
967         INSN_3(STX, MEM,  DW),                  \
968         INSN_3(STX, XADD, W),                   \
969         INSN_3(STX, XADD, DW),                  \
970         /*   Immediate based. */                \
971         INSN_3(ST, MEM, B),                     \
972         INSN_3(ST, MEM, H),                     \
973         INSN_3(ST, MEM, W),                     \
974         INSN_3(ST, MEM, DW),                    \
975         /* Load instructions. */                \
976         /*   Register based. */                 \
977         INSN_3(LDX, MEM, B),                    \
978         INSN_3(LDX, MEM, H),                    \
979         INSN_3(LDX, MEM, W),                    \
980         INSN_3(LDX, MEM, DW),                   \
981         /*   Immediate based. */                \
982         INSN_3(LD, IMM, DW)
983 
984 bool bpf_opcode_in_insntable(u8 code)
985 {
986 #define BPF_INSN_2_TBL(x, y)    [BPF_##x | BPF_##y] = true
987 #define BPF_INSN_3_TBL(x, y, z) [BPF_##x | BPF_##y | BPF_##z] = true
988         static const bool public_insntable[256] = {
989                 [0 ... 255] = false,
990                 /* Now overwrite non-defaults ... */
991                 BPF_INSN_MAP(BPF_INSN_2_TBL, BPF_INSN_3_TBL),
992                 /* UAPI exposed, but rewritten opcodes. cBPF carry-over. */
993                 [BPF_LD | BPF_ABS | BPF_B] = true,
994                 [BPF_LD | BPF_ABS | BPF_H] = true,
995                 [BPF_LD | BPF_ABS | BPF_W] = true,
996                 [BPF_LD | BPF_IND | BPF_B] = true,
997                 [BPF_LD | BPF_IND | BPF_H] = true,
998                 [BPF_LD | BPF_IND | BPF_W] = true,
999         };
1000 #undef BPF_INSN_3_TBL
1001 #undef BPF_INSN_2_TBL
1002         return public_insntable[code];
1003 }
1004 
1005 #ifndef CONFIG_BPF_JIT_ALWAYS_ON
1006 /**
1007  *      __bpf_prog_run - run eBPF program on a given context
1008  *      @ctx: is the data we are operating on
1009  *      @insn: is the array of eBPF instructions
1010  *
1011  * Decode and execute eBPF instructions.
1012  */
1013 static u64 ___bpf_prog_run(u64 *regs, const struct bpf_insn *insn, u64 *stack)
1014 {
1015         u64 tmp;
1016 #define BPF_INSN_2_LBL(x, y)    [BPF_##x | BPF_##y] = &&x##_##y
1017 #define BPF_INSN_3_LBL(x, y, z) [BPF_##x | BPF_##y | BPF_##z] = &&x##_##y##_##z
1018         static const void *jumptable[256] = {
1019                 [0 ... 255] = &&default_label,
1020                 /* Now overwrite non-defaults ... */
1021                 BPF_INSN_MAP(BPF_INSN_2_LBL, BPF_INSN_3_LBL),
1022                 /* Non-UAPI available opcodes. */
1023                 [BPF_JMP | BPF_CALL_ARGS] = &&JMP_CALL_ARGS,
1024                 [BPF_JMP | BPF_TAIL_CALL] = &&JMP_TAIL_CALL,
1025         };
1026 #undef BPF_INSN_3_LBL
1027 #undef BPF_INSN_2_LBL
1028         u32 tail_call_cnt = 0;
1029 
1030 #define CONT     ({ insn++; goto select_insn; })
1031 #define CONT_JMP ({ insn++; goto select_insn; })
1032 
1033 select_insn:
1034         goto *jumptable[insn->code];
1035 
1036         /* ALU */
1037 #define ALU(OPCODE, OP)                 \
1038         ALU64_##OPCODE##_X:             \
1039                 DST = DST OP SRC;       \
1040                 CONT;                   \
1041         ALU_##OPCODE##_X:               \
1042                 DST = (u32) DST OP (u32) SRC;   \
1043                 CONT;                   \
1044         ALU64_##OPCODE##_K:             \
1045                 DST = DST OP IMM;               \
1046                 CONT;                   \
1047         ALU_##OPCODE##_K:               \
1048                 DST = (u32) DST OP (u32) IMM;   \
1049                 CONT;
1050 
1051         ALU(ADD,  +)
1052         ALU(SUB,  -)
1053         ALU(AND,  &)
1054         ALU(OR,   |)
1055         ALU(LSH, <<)
1056         ALU(RSH, >>)
1057         ALU(XOR,  ^)
1058         ALU(MUL,  *)
1059 #undef ALU
1060         ALU_NEG:
1061                 DST = (u32) -DST;
1062                 CONT;
1063         ALU64_NEG:
1064                 DST = -DST;
1065                 CONT;
1066         ALU_MOV_X:
1067                 DST = (u32) SRC;
1068                 CONT;
1069         ALU_MOV_K:
1070                 DST = (u32) IMM;
1071                 CONT;
1072         ALU64_MOV_X:
1073                 DST = SRC;
1074                 CONT;
1075         ALU64_MOV_K:
1076                 DST = IMM;
1077                 CONT;
1078         LD_IMM_DW:
1079                 DST = (u64) (u32) insn[0].imm | ((u64) (u32) insn[1].imm) << 32;
1080                 insn++;
1081                 CONT;
1082         ALU64_ARSH_X:
1083                 (*(s64 *) &DST) >>= SRC;
1084                 CONT;
1085         ALU64_ARSH_K:
1086                 (*(s64 *) &DST) >>= IMM;
1087                 CONT;
1088         ALU64_MOD_X:
1089                 div64_u64_rem(DST, SRC, &tmp);
1090                 DST = tmp;
1091                 CONT;
1092         ALU_MOD_X:
1093                 tmp = (u32) DST;
1094                 DST = do_div(tmp, (u32) SRC);
1095                 CONT;
1096         ALU64_MOD_K:
1097                 div64_u64_rem(DST, IMM, &tmp);
1098                 DST = tmp;
1099                 CONT;
1100         ALU_MOD_K:
1101                 tmp = (u32) DST;
1102                 DST = do_div(tmp, (u32) IMM);
1103                 CONT;
1104         ALU64_DIV_X:
1105                 DST = div64_u64(DST, SRC);
1106                 CONT;
1107         ALU_DIV_X:
1108                 tmp = (u32) DST;
1109                 do_div(tmp, (u32) SRC);
1110                 DST = (u32) tmp;
1111                 CONT;
1112         ALU64_DIV_K:
1113                 DST = div64_u64(DST, IMM);
1114                 CONT;
1115         ALU_DIV_K:
1116                 tmp = (u32) DST;
1117                 do_div(tmp, (u32) IMM);
1118                 DST = (u32) tmp;
1119                 CONT;
1120         ALU_END_TO_BE:
1121                 switch (IMM) {
1122                 case 16:
1123                         DST = (__force u16) cpu_to_be16(DST);
1124                         break;
1125                 case 32:
1126                         DST = (__force u32) cpu_to_be32(DST);
1127                         break;
1128                 case 64:
1129                         DST = (__force u64) cpu_to_be64(DST);
1130                         break;
1131                 }
1132                 CONT;
1133         ALU_END_TO_LE:
1134                 switch (IMM) {
1135                 case 16:
1136                         DST = (__force u16) cpu_to_le16(DST);
1137                         break;
1138                 case 32:
1139                         DST = (__force u32) cpu_to_le32(DST);
1140                         break;
1141                 case 64:
1142                         DST = (__force u64) cpu_to_le64(DST);
1143                         break;
1144                 }
1145                 CONT;
1146 
1147         /* CALL */
1148         JMP_CALL:
1149                 /* Function call scratches BPF_R1-BPF_R5 registers,
1150                  * preserves BPF_R6-BPF_R9, and stores return value
1151                  * into BPF_R0.
1152                  */
1153                 BPF_R0 = (__bpf_call_base + insn->imm)(BPF_R1, BPF_R2, BPF_R3,
1154                                                        BPF_R4, BPF_R5);
1155                 CONT;
1156 
1157         JMP_CALL_ARGS:
1158                 BPF_R0 = (__bpf_call_base_args + insn->imm)(BPF_R1, BPF_R2,
1159                                                             BPF_R3, BPF_R4,
1160                                                             BPF_R5,
1161                                                             insn + insn->off + 1);
1162                 CONT;
1163 
1164         JMP_TAIL_CALL: {
1165                 struct bpf_map *map = (struct bpf_map *) (unsigned long) BPF_R2;
1166                 struct bpf_array *array = container_of(map, struct bpf_array, map);
1167                 struct bpf_prog *prog;
1168                 u32 index = BPF_R3;
1169 
1170                 if (unlikely(index >= array->map.max_entries))
1171                         goto out;
1172                 if (unlikely(tail_call_cnt > MAX_TAIL_CALL_CNT))
1173                         goto out;
1174 
1175                 tail_call_cnt++;
1176 
1177                 prog = READ_ONCE(array->ptrs[index]);
1178                 if (!prog)
1179                         goto out;
1180 
1181                 /* ARG1 at this point is guaranteed to point to CTX from
1182                  * the verifier side due to the fact that the tail call is
1183                  * handeled like a helper, that is, bpf_tail_call_proto,
1184                  * where arg1_type is ARG_PTR_TO_CTX.
1185                  */
1186                 insn = prog->insnsi;
1187                 goto select_insn;
1188 out:
1189                 CONT;
1190         }
1191         /* JMP */
1192         JMP_JA:
1193                 insn += insn->off;
1194                 CONT;
1195         JMP_JEQ_X:
1196                 if (DST == SRC) {
1197                         insn += insn->off;
1198                         CONT_JMP;
1199                 }
1200                 CONT;
1201         JMP_JEQ_K:
1202                 if (DST == IMM) {
1203                         insn += insn->off;
1204                         CONT_JMP;
1205                 }
1206                 CONT;
1207         JMP_JNE_X:
1208                 if (DST != SRC) {
1209                         insn += insn->off;
1210                         CONT_JMP;
1211                 }
1212                 CONT;
1213         JMP_JNE_K:
1214                 if (DST != IMM) {
1215                         insn += insn->off;
1216                         CONT_JMP;
1217                 }
1218                 CONT;
1219         JMP_JGT_X:
1220                 if (DST > SRC) {
1221                         insn += insn->off;
1222                         CONT_JMP;
1223                 }
1224                 CONT;
1225         JMP_JGT_K:
1226                 if (DST > IMM) {
1227                         insn += insn->off;
1228                         CONT_JMP;
1229                 }
1230                 CONT;
1231         JMP_JLT_X:
1232                 if (DST < SRC) {
1233                         insn += insn->off;
1234                         CONT_JMP;
1235                 }
1236                 CONT;
1237         JMP_JLT_K:
1238                 if (DST < IMM) {
1239                         insn += insn->off;
1240                         CONT_JMP;
1241                 }
1242                 CONT;
1243         JMP_JGE_X:
1244                 if (DST >= SRC) {
1245                         insn += insn->off;
1246                         CONT_JMP;
1247                 }
1248                 CONT;
1249         JMP_JGE_K:
1250                 if (DST >= IMM) {
1251                         insn += insn->off;
1252                         CONT_JMP;
1253                 }
1254                 CONT;
1255         JMP_JLE_X:
1256                 if (DST <= SRC) {
1257                         insn += insn->off;
1258                         CONT_JMP;
1259                 }
1260                 CONT;
1261         JMP_JLE_K:
1262                 if (DST <= IMM) {
1263                         insn += insn->off;
1264                         CONT_JMP;
1265                 }
1266                 CONT;
1267         JMP_JSGT_X:
1268                 if (((s64) DST) > ((s64) SRC)) {
1269                         insn += insn->off;
1270                         CONT_JMP;
1271                 }
1272                 CONT;
1273         JMP_JSGT_K:
1274                 if (((s64) DST) > ((s64) IMM)) {
1275                         insn += insn->off;
1276                         CONT_JMP;
1277                 }
1278                 CONT;
1279         JMP_JSLT_X:
1280                 if (((s64) DST) < ((s64) SRC)) {
1281                         insn += insn->off;
1282                         CONT_JMP;
1283                 }
1284                 CONT;
1285         JMP_JSLT_K:
1286                 if (((s64) DST) < ((s64) IMM)) {
1287                         insn += insn->off;
1288                         CONT_JMP;
1289                 }
1290                 CONT;
1291         JMP_JSGE_X:
1292                 if (((s64) DST) >= ((s64) SRC)) {
1293                         insn += insn->off;
1294                         CONT_JMP;
1295                 }
1296                 CONT;
1297         JMP_JSGE_K:
1298                 if (((s64) DST) >= ((s64) IMM)) {
1299                         insn += insn->off;
1300                         CONT_JMP;
1301                 }
1302                 CONT;
1303         JMP_JSLE_X:
1304                 if (((s64) DST) <= ((s64) SRC)) {
1305                         insn += insn->off;
1306                         CONT_JMP;
1307                 }
1308                 CONT;
1309         JMP_JSLE_K:
1310                 if (((s64) DST) <= ((s64) IMM)) {
1311                         insn += insn->off;
1312                         CONT_JMP;
1313                 }
1314                 CONT;
1315         JMP_JSET_X:
1316                 if (DST & SRC) {
1317                         insn += insn->off;
1318                         CONT_JMP;
1319                 }
1320                 CONT;
1321         JMP_JSET_K:
1322                 if (DST & IMM) {
1323                         insn += insn->off;
1324                         CONT_JMP;
1325                 }
1326                 CONT;
1327         JMP_EXIT:
1328                 return BPF_R0;
1329 
1330         /* STX and ST and LDX*/
1331 #define LDST(SIZEOP, SIZE)                                              \
1332         STX_MEM_##SIZEOP:                                               \
1333                 *(SIZE *)(unsigned long) (DST + insn->off) = SRC;       \
1334                 CONT;                                                   \
1335         ST_MEM_##SIZEOP:                                                \
1336                 *(SIZE *)(unsigned long) (DST + insn->off) = IMM;       \
1337                 CONT;                                                   \
1338         LDX_MEM_##SIZEOP:                                               \
1339                 DST = *(SIZE *)(unsigned long) (SRC + insn->off);       \
1340                 CONT;
1341 
1342         LDST(B,   u8)
1343         LDST(H,  u16)
1344         LDST(W,  u32)
1345         LDST(DW, u64)
1346 #undef LDST
1347         STX_XADD_W: /* lock xadd *(u32 *)(dst_reg + off16) += src_reg */
1348                 atomic_add((u32) SRC, (atomic_t *)(unsigned long)
1349                            (DST + insn->off));
1350                 CONT;
1351         STX_XADD_DW: /* lock xadd *(u64 *)(dst_reg + off16) += src_reg */
1352                 atomic64_add((u64) SRC, (atomic64_t *)(unsigned long)
1353                              (DST + insn->off));
1354                 CONT;
1355 
1356         default_label:
1357                 /* If we ever reach this, we have a bug somewhere. Die hard here
1358                  * instead of just returning 0; we could be somewhere in a subprog,
1359                  * so execution could continue otherwise which we do /not/ want.
1360                  *
1361                  * Note, verifier whitelists all opcodes in bpf_opcode_in_insntable().
1362                  */
1363                 pr_warn("BPF interpreter: unknown opcode %02x\n", insn->code);
1364                 BUG_ON(1);
1365                 return 0;
1366 }
1367 STACK_FRAME_NON_STANDARD(___bpf_prog_run); /* jump table */
1368 
1369 #define PROG_NAME(stack_size) __bpf_prog_run##stack_size
1370 #define DEFINE_BPF_PROG_RUN(stack_size) \
1371 static unsigned int PROG_NAME(stack_size)(const void *ctx, const struct bpf_insn *insn) \
1372 { \
1373         u64 stack[stack_size / sizeof(u64)]; \
1374         u64 regs[MAX_BPF_REG]; \
1375 \
1376         FP = (u64) (unsigned long) &stack[ARRAY_SIZE(stack)]; \
1377         ARG1 = (u64) (unsigned long) ctx; \
1378         return ___bpf_prog_run(regs, insn, stack); \
1379 }
1380 
1381 #define PROG_NAME_ARGS(stack_size) __bpf_prog_run_args##stack_size
1382 #define DEFINE_BPF_PROG_RUN_ARGS(stack_size) \
1383 static u64 PROG_NAME_ARGS(stack_size)(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5, \
1384                                       const struct bpf_insn *insn) \
1385 { \
1386         u64 stack[stack_size / sizeof(u64)]; \
1387         u64 regs[MAX_BPF_REG]; \
1388 \
1389         FP = (u64) (unsigned long) &stack[ARRAY_SIZE(stack)]; \
1390         BPF_R1 = r1; \
1391         BPF_R2 = r2; \
1392         BPF_R3 = r3; \
1393         BPF_R4 = r4; \
1394         BPF_R5 = r5; \
1395         return ___bpf_prog_run(regs, insn, stack); \
1396 }
1397 
1398 #define EVAL1(FN, X) FN(X)
1399 #define EVAL2(FN, X, Y...) FN(X) EVAL1(FN, Y)
1400 #define EVAL3(FN, X, Y...) FN(X) EVAL2(FN, Y)
1401 #define EVAL4(FN, X, Y...) FN(X) EVAL3(FN, Y)
1402 #define EVAL5(FN, X, Y...) FN(X) EVAL4(FN, Y)
1403 #define EVAL6(FN, X, Y...) FN(X) EVAL5(FN, Y)
1404 
1405 EVAL6(DEFINE_BPF_PROG_RUN, 32, 64, 96, 128, 160, 192);
1406 EVAL6(DEFINE_BPF_PROG_RUN, 224, 256, 288, 320, 352, 384);
1407 EVAL4(DEFINE_BPF_PROG_RUN, 416, 448, 480, 512);
1408 
1409 EVAL6(DEFINE_BPF_PROG_RUN_ARGS, 32, 64, 96, 128, 160, 192);
1410 EVAL6(DEFINE_BPF_PROG_RUN_ARGS, 224, 256, 288, 320, 352, 384);
1411 EVAL4(DEFINE_BPF_PROG_RUN_ARGS, 416, 448, 480, 512);
1412 
1413 #define PROG_NAME_LIST(stack_size) PROG_NAME(stack_size),
1414 
1415 static unsigned int (*interpreters[])(const void *ctx,
1416                                       const struct bpf_insn *insn) = {
1417 EVAL6(PROG_NAME_LIST, 32, 64, 96, 128, 160, 192)
1418 EVAL6(PROG_NAME_LIST, 224, 256, 288, 320, 352, 384)
1419 EVAL4(PROG_NAME_LIST, 416, 448, 480, 512)
1420 };
1421 #undef PROG_NAME_LIST
1422 #define PROG_NAME_LIST(stack_size) PROG_NAME_ARGS(stack_size),
1423 static u64 (*interpreters_args[])(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5,
1424                                   const struct bpf_insn *insn) = {
1425 EVAL6(PROG_NAME_LIST, 32, 64, 96, 128, 160, 192)
1426 EVAL6(PROG_NAME_LIST, 224, 256, 288, 320, 352, 384)
1427 EVAL4(PROG_NAME_LIST, 416, 448, 480, 512)
1428 };
1429 #undef PROG_NAME_LIST
1430 
1431 void bpf_patch_call_args(struct bpf_insn *insn, u32 stack_depth)
1432 {
1433         stack_depth = max_t(u32, stack_depth, 1);
1434         insn->off = (s16) insn->imm;
1435         insn->imm = interpreters_args[(round_up(stack_depth, 32) / 32) - 1] -
1436                 __bpf_call_base_args;
1437         insn->code = BPF_JMP | BPF_CALL_ARGS;
1438 }
1439 
1440 #else
1441 static unsigned int __bpf_prog_ret0_warn(const void *ctx,
1442                                          const struct bpf_insn *insn)
1443 {
1444         /* If this handler ever gets executed, then BPF_JIT_ALWAYS_ON
1445          * is not working properly, so warn about it!
1446          */
1447         WARN_ON_ONCE(1);
1448         return 0;
1449 }
1450 #endif
1451 
1452 bool bpf_prog_array_compatible(struct bpf_array *array,
1453                                const struct bpf_prog *fp)
1454 {
1455         if (fp->kprobe_override)
1456                 return false;
1457 
1458         if (!array->owner_prog_type) {
1459                 /* There's no owner yet where we could check for
1460                  * compatibility.
1461                  */
1462                 array->owner_prog_type = fp->type;
1463                 array->owner_jited = fp->jited;
1464 
1465                 return true;
1466         }
1467 
1468         return array->owner_prog_type == fp->type &&
1469                array->owner_jited == fp->jited;
1470 }
1471 
1472 static int bpf_check_tail_call(const struct bpf_prog *fp)
1473 {
1474         struct bpf_prog_aux *aux = fp->aux;
1475         int i;
1476 
1477         for (i = 0; i < aux->used_map_cnt; i++) {
1478                 struct bpf_map *map = aux->used_maps[i];
1479                 struct bpf_array *array;
1480 
1481                 if (map->map_type != BPF_MAP_TYPE_PROG_ARRAY)
1482                         continue;
1483 
1484                 array = container_of(map, struct bpf_array, map);
1485                 if (!bpf_prog_array_compatible(array, fp))
1486                         return -EINVAL;
1487         }
1488 
1489         return 0;
1490 }
1491 
1492 static void bpf_prog_select_func(struct bpf_prog *fp)
1493 {
1494 #ifndef CONFIG_BPF_JIT_ALWAYS_ON
1495         u32 stack_depth = max_t(u32, fp->aux->stack_depth, 1);
1496 
1497         fp->bpf_func = interpreters[(round_up(stack_depth, 32) / 32) - 1];
1498 #else
1499         fp->bpf_func = __bpf_prog_ret0_warn;
1500 #endif
1501 }
1502 
1503 /**
1504  *      bpf_prog_select_runtime - select exec runtime for BPF program
1505  *      @fp: bpf_prog populated with internal BPF program
1506  *      @err: pointer to error variable
1507  *
1508  * Try to JIT eBPF program, if JIT is not available, use interpreter.
1509  * The BPF program will be executed via BPF_PROG_RUN() macro.
1510  */
1511 struct bpf_prog *bpf_prog_select_runtime(struct bpf_prog *fp, int *err)
1512 {
1513         /* In case of BPF to BPF calls, verifier did all the prep
1514          * work with regards to JITing, etc.
1515          */
1516         if (fp->bpf_func)
1517                 goto finalize;
1518 
1519         bpf_prog_select_func(fp);
1520 
1521         /* eBPF JITs can rewrite the program in case constant
1522          * blinding is active. However, in case of error during
1523          * blinding, bpf_int_jit_compile() must always return a
1524          * valid program, which in this case would simply not
1525          * be JITed, but falls back to the interpreter.
1526          */
1527         if (!bpf_prog_is_dev_bound(fp->aux)) {
1528                 fp = bpf_int_jit_compile(fp);
1529 #ifdef CONFIG_BPF_JIT_ALWAYS_ON
1530                 if (!fp->jited) {
1531                         *err = -ENOTSUPP;
1532                         return fp;
1533                 }
1534 #endif
1535         } else {
1536                 *err = bpf_prog_offload_compile(fp);
1537                 if (*err)
1538                         return fp;
1539         }
1540 
1541 finalize:
1542         bpf_prog_lock_ro(fp);
1543 
1544         /* The tail call compatibility check can only be done at
1545          * this late stage as we need to determine, if we deal
1546          * with JITed or non JITed program concatenations and not
1547          * all eBPF JITs might immediately support all features.
1548          */
1549         *err = bpf_check_tail_call(fp);
1550 
1551         return fp;
1552 }
1553 EXPORT_SYMBOL_GPL(bpf_prog_select_runtime);
1554 
1555 static unsigned int __bpf_prog_ret1(const void *ctx,
1556                                     const struct bpf_insn *insn)
1557 {
1558         return 1;
1559 }
1560 
1561 static struct bpf_prog_dummy {
1562         struct bpf_prog prog;
1563 } dummy_bpf_prog = {
1564         .prog = {
1565                 .bpf_func = __bpf_prog_ret1,
1566         },
1567 };
1568 
1569 /* to avoid allocating empty bpf_prog_array for cgroups that
1570  * don't have bpf program attached use one global 'empty_prog_array'
1571  * It will not be modified the caller of bpf_prog_array_alloc()
1572  * (since caller requested prog_cnt == 0)
1573  * that pointer should be 'freed' by bpf_prog_array_free()
1574  */
1575 static struct {
1576         struct bpf_prog_array hdr;
1577         struct bpf_prog *null_prog;
1578 } empty_prog_array = {
1579         .null_prog = NULL,
1580 };
1581 
1582 struct bpf_prog_array *bpf_prog_array_alloc(u32 prog_cnt, gfp_t flags)
1583 {
1584         if (prog_cnt)
1585                 return kzalloc(sizeof(struct bpf_prog_array) +
1586                                sizeof(struct bpf_prog_array_item) *
1587                                (prog_cnt + 1),
1588                                flags);
1589 
1590         return &empty_prog_array.hdr;
1591 }
1592 
1593 void bpf_prog_array_free(struct bpf_prog_array __rcu *progs)
1594 {
1595         if (!progs ||
1596             progs == (struct bpf_prog_array __rcu *)&empty_prog_array.hdr)
1597                 return;
1598         kfree_rcu(progs, rcu);
1599 }
1600 
1601 int bpf_prog_array_length(struct bpf_prog_array __rcu *array)
1602 {
1603         struct bpf_prog_array_item *item;
1604         u32 cnt = 0;
1605 
1606         rcu_read_lock();
1607         item = rcu_dereference(array)->items;
1608         for (; item->prog; item++)
1609                 if (item->prog != &dummy_bpf_prog.prog)
1610                         cnt++;
1611         rcu_read_unlock();
1612         return cnt;
1613 }
1614 
1615 
1616 static bool bpf_prog_array_copy_core(struct bpf_prog_array __rcu *array,
1617                                      u32 *prog_ids,
1618                                      u32 request_cnt)
1619 {
1620         struct bpf_prog_array_item *item;
1621         int i = 0;
1622 
1623         item = rcu_dereference_check(array, 1)->items;
1624         for (; item->prog; item++) {
1625                 if (item->prog == &dummy_bpf_prog.prog)
1626                         continue;
1627                 prog_ids[i] = item->prog->aux->id;
1628                 if (++i == request_cnt) {
1629                         item++;
1630                         break;
1631                 }
1632         }
1633 
1634         return !!(item->prog);
1635 }
1636 
1637 int bpf_prog_array_copy_to_user(struct bpf_prog_array __rcu *array,
1638                                 __u32 __user *prog_ids, u32 cnt)
1639 {
1640         unsigned long err = 0;
1641         bool nospc;
1642         u32 *ids;
1643 
1644         /* users of this function are doing:
1645          * cnt = bpf_prog_array_length();
1646          * if (cnt > 0)
1647          *     bpf_prog_array_copy_to_user(..., cnt);
1648          * so below kcalloc doesn't need extra cnt > 0 check, but
1649          * bpf_prog_array_length() releases rcu lock and
1650          * prog array could have been swapped with empty or larger array,
1651          * so always copy 'cnt' prog_ids to the user.
1652          * In a rare race the user will see zero prog_ids
1653          */
1654         ids = kcalloc(cnt, sizeof(u32), GFP_USER | __GFP_NOWARN);
1655         if (!ids)
1656                 return -ENOMEM;
1657         rcu_read_lock();
1658         nospc = bpf_prog_array_copy_core(array, ids, cnt);
1659         rcu_read_unlock();
1660         err = copy_to_user(prog_ids, ids, cnt * sizeof(u32));
1661         kfree(ids);
1662         if (err)
1663                 return -EFAULT;
1664         if (nospc)
1665                 return -ENOSPC;
1666         return 0;
1667 }
1668 
1669 void bpf_prog_array_delete_safe(struct bpf_prog_array __rcu *array,
1670                                 struct bpf_prog *old_prog)
1671 {
1672         struct bpf_prog_array_item *item = array->items;
1673 
1674         for (; item->prog; item++)
1675                 if (item->prog == old_prog) {
1676                         WRITE_ONCE(item->prog, &dummy_bpf_prog.prog);
1677                         break;
1678                 }
1679 }
1680 
1681 int bpf_prog_array_copy(struct bpf_prog_array __rcu *old_array,
1682                         struct bpf_prog *exclude_prog,
1683                         struct bpf_prog *include_prog,
1684                         struct bpf_prog_array **new_array)
1685 {
1686         int new_prog_cnt, carry_prog_cnt = 0;
1687         struct bpf_prog_array_item *existing;
1688         struct bpf_prog_array *array;
1689         bool found_exclude = false;
1690         int new_prog_idx = 0;
1691 
1692         /* Figure out how many existing progs we need to carry over to
1693          * the new array.
1694          */
1695         if (old_array) {
1696                 existing = old_array->items;
1697                 for (; existing->prog; existing++) {
1698                         if (existing->prog == exclude_prog) {
1699                                 found_exclude = true;
1700                                 continue;
1701                         }
1702                         if (existing->prog != &dummy_bpf_prog.prog)
1703                                 carry_prog_cnt++;
1704                         if (existing->prog == include_prog)
1705                                 return -EEXIST;
1706                 }
1707         }
1708 
1709         if (exclude_prog && !found_exclude)
1710                 return -ENOENT;
1711 
1712         /* How many progs (not NULL) will be in the new array? */
1713         new_prog_cnt = carry_prog_cnt;
1714         if (include_prog)
1715                 new_prog_cnt += 1;
1716 
1717         /* Do we have any prog (not NULL) in the new array? */
1718         if (!new_prog_cnt) {
1719                 *new_array = NULL;
1720                 return 0;
1721         }
1722 
1723         /* +1 as the end of prog_array is marked with NULL */
1724         array = bpf_prog_array_alloc(new_prog_cnt + 1, GFP_KERNEL);
1725         if (!array)
1726                 return -ENOMEM;
1727 
1728         /* Fill in the new prog array */
1729         if (carry_prog_cnt) {
1730                 existing = old_array->items;
1731                 for (; existing->prog; existing++)
1732                         if (existing->prog != exclude_prog &&
1733                             existing->prog != &dummy_bpf_prog.prog) {
1734                                 array->items[new_prog_idx++].prog =
1735                                         existing->prog;
1736                         }
1737         }
1738         if (include_prog)
1739                 array->items[new_prog_idx++].prog = include_prog;
1740         array->items[new_prog_idx].prog = NULL;
1741         *new_array = array;
1742         return 0;
1743 }
1744 
1745 int bpf_prog_array_copy_info(struct bpf_prog_array __rcu *array,
1746                              u32 *prog_ids, u32 request_cnt,
1747                              u32 *prog_cnt)
1748 {
1749         u32 cnt = 0;
1750 
1751         if (array)
1752                 cnt = bpf_prog_array_length(array);
1753 
1754         *prog_cnt = cnt;
1755 
1756         /* return early if user requested only program count or nothing to copy */
1757         if (!request_cnt || !cnt)
1758                 return 0;
1759 
1760         /* this function is called under trace/bpf_trace.c: bpf_event_mutex */
1761         return bpf_prog_array_copy_core(array, prog_ids, request_cnt) ? -ENOSPC
1762                                                                      : 0;
1763 }
1764 
1765 static void bpf_prog_free_deferred(struct work_struct *work)
1766 {
1767         struct bpf_prog_aux *aux;
1768         int i;
1769 
1770         aux = container_of(work, struct bpf_prog_aux, work);
1771         if (bpf_prog_is_dev_bound(aux))
1772                 bpf_prog_offload_destroy(aux->prog);
1773 #ifdef CONFIG_PERF_EVENTS
1774         if (aux->prog->has_callchain_buf)
1775                 put_callchain_buffers();
1776 #endif
1777         for (i = 0; i < aux->func_cnt; i++)
1778                 bpf_jit_free(aux->func[i]);
1779         if (aux->func_cnt) {
1780                 kfree(aux->func);
1781                 bpf_prog_unlock_free(aux->prog);
1782         } else {
1783                 bpf_jit_free(aux->prog);
1784         }
1785 }
1786 
1787 /* Free internal BPF program */
1788 void bpf_prog_free(struct bpf_prog *fp)
1789 {
1790         struct bpf_prog_aux *aux = fp->aux;
1791 
1792         INIT_WORK(&aux->work, bpf_prog_free_deferred);
1793         schedule_work(&aux->work);
1794 }
1795 EXPORT_SYMBOL_GPL(bpf_prog_free);
1796 
1797 /* RNG for unpriviledged user space with separated state from prandom_u32(). */
1798 static DEFINE_PER_CPU(struct rnd_state, bpf_user_rnd_state);
1799 
1800 void bpf_user_rnd_init_once(void)
1801 {
1802         prandom_init_once(&bpf_user_rnd_state);
1803 }
1804 
1805 BPF_CALL_0(bpf_user_rnd_u32)
1806 {
1807         /* Should someone ever have the rather unwise idea to use some
1808          * of the registers passed into this function, then note that
1809          * this function is called from native eBPF and classic-to-eBPF
1810          * transformations. Register assignments from both sides are
1811          * different, f.e. classic always sets fn(ctx, A, X) here.
1812          */
1813         struct rnd_state *state;
1814         u32 res;
1815 
1816         state = &get_cpu_var(bpf_user_rnd_state);
1817         res = prandom_u32_state(state);
1818         put_cpu_var(bpf_user_rnd_state);
1819 
1820         return res;
1821 }
1822 
1823 /* Weak definitions of helper functions in case we don't have bpf syscall. */
1824 const struct bpf_func_proto bpf_map_lookup_elem_proto __weak;
1825 const struct bpf_func_proto bpf_map_update_elem_proto __weak;
1826 const struct bpf_func_proto bpf_map_delete_elem_proto __weak;
1827 const struct bpf_func_proto bpf_map_push_elem_proto __weak;
1828 const struct bpf_func_proto bpf_map_pop_elem_proto __weak;
1829 const struct bpf_func_proto bpf_map_peek_elem_proto __weak;
1830 
1831 const struct bpf_func_proto bpf_get_prandom_u32_proto __weak;
1832 const struct bpf_func_proto bpf_get_smp_processor_id_proto __weak;
1833 const struct bpf_func_proto bpf_get_numa_node_id_proto __weak;
1834 const struct bpf_func_proto bpf_ktime_get_ns_proto __weak;
1835 
1836 const struct bpf_func_proto bpf_get_current_pid_tgid_proto __weak;
1837 const struct bpf_func_proto bpf_get_current_uid_gid_proto __weak;
1838 const struct bpf_func_proto bpf_get_current_comm_proto __weak;
1839 const struct bpf_func_proto bpf_get_current_cgroup_id_proto __weak;
1840 const struct bpf_func_proto bpf_get_local_storage_proto __weak;
1841 
1842 const struct bpf_func_proto * __weak bpf_get_trace_printk_proto(void)
1843 {
1844         return NULL;
1845 }
1846 
1847 u64 __weak
1848 bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size,
1849                  void *ctx, u64 ctx_size, bpf_ctx_copy_t ctx_copy)
1850 {
1851         return -ENOTSUPP;
1852 }
1853 EXPORT_SYMBOL_GPL(bpf_event_output);
1854 
1855 /* Always built-in helper functions. */
1856 const struct bpf_func_proto bpf_tail_call_proto = {
1857         .func           = NULL,
1858         .gpl_only       = false,
1859         .ret_type       = RET_VOID,
1860         .arg1_type      = ARG_PTR_TO_CTX,
1861         .arg2_type      = ARG_CONST_MAP_PTR,
1862         .arg3_type      = ARG_ANYTHING,
1863 };
1864 
1865 /* Stub for JITs that only support cBPF. eBPF programs are interpreted.
1866  * It is encouraged to implement bpf_int_jit_compile() instead, so that
1867  * eBPF and implicitly also cBPF can get JITed!
1868  */
1869 struct bpf_prog * __weak bpf_int_jit_compile(struct bpf_prog *prog)
1870 {
1871         return prog;
1872 }
1873 
1874 /* Stub for JITs that support eBPF. All cBPF code gets transformed into
1875  * eBPF by the kernel and is later compiled by bpf_int_jit_compile().
1876  */
1877 void __weak bpf_jit_compile(struct bpf_prog *prog)
1878 {
1879 }
1880 
1881 bool __weak bpf_helper_changes_pkt_data(void *func)
1882 {
1883         return false;
1884 }
1885 
1886 /* To execute LD_ABS/LD_IND instructions __bpf_prog_run() may call
1887  * skb_copy_bits(), so provide a weak definition of it for NET-less config.
1888  */
1889 int __weak skb_copy_bits(const struct sk_buff *skb, int offset, void *to,
1890                          int len)
1891 {
1892         return -EFAULT;
1893 }
1894 
1895 /* All definitions of tracepoints related to BPF. */
1896 #define CREATE_TRACE_POINTS
1897 #include <linux/bpf_trace.h>
1898 
1899 EXPORT_TRACEPOINT_SYMBOL_GPL(xdp_exception);
1900 

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