1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* /proc interface for AFS
3 *
4 * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
6 */
7
8 #include <linux/slab.h>
9 #include <linux/module.h>
10 #include <linux/proc_fs.h>
11 #include <linux/seq_file.h>
12 #include <linux/sched.h>
13 #include <linux/uaccess.h>
14 #include "internal.h"
15
16 struct afs_vl_seq_net_private {
17 struct seq_net_private seq; /* Must be first */
18 struct afs_vlserver_list *vllist;
19 };
20
21 static inline struct afs_net *afs_seq2net(struct seq_file *m)
22 {
23 return afs_net(seq_file_net(m));
24 }
25
26 static inline struct afs_net *afs_seq2net_single(struct seq_file *m)
27 {
28 return afs_net(seq_file_single_net(m));
29 }
30
31 /*
32 * Display the list of cells known to the namespace.
33 */
34 static int afs_proc_cells_show(struct seq_file *m, void *v)
35 {
36 struct afs_vlserver_list *vllist;
37 struct afs_cell *cell;
38
39 if (v == SEQ_START_TOKEN) {
40 /* display header on line 1 */
41 seq_puts(m, "USE ACT TTL SV ST NAME\n");
42 return 0;
43 }
44
45 cell = list_entry(v, struct afs_cell, proc_link);
46 vllist = rcu_dereference(cell->vl_servers);
47
48 /* display one cell per line on subsequent lines */
49 seq_printf(m, "%3u %3u %6lld %2u %2u %s\n",
50 refcount_read(&cell->ref),
51 atomic_read(&cell->active),
52 cell->dns_expiry - ktime_get_real_seconds(),
53 vllist ? vllist->nr_servers : 0,
54 cell->state,
55 cell->name);
56 return 0;
57 }
58
59 static void *afs_proc_cells_start(struct seq_file *m, loff_t *_pos)
60 __acquires(rcu)
61 {
62 rcu_read_lock();
63 return seq_hlist_start_head_rcu(&afs_seq2net(m)->proc_cells, *_pos);
64 }
65
66 static void *afs_proc_cells_next(struct seq_file *m, void *v, loff_t *pos)
67 {
68 return seq_hlist_next_rcu(v, &afs_seq2net(m)->proc_cells, pos);
69 }
70
71 static void afs_proc_cells_stop(struct seq_file *m, void *v)
72 __releases(rcu)
73 {
74 rcu_read_unlock();
75 }
76
77 static const struct seq_operations afs_proc_cells_ops = {
78 .start = afs_proc_cells_start,
79 .next = afs_proc_cells_next,
80 .stop = afs_proc_cells_stop,
81 .show = afs_proc_cells_show,
82 };
83
84 /*
85 * handle writes to /proc/fs/afs/cells
86 * - to add cells: echo "add <cellname> <IP>[:<IP>][:<IP>]"
87 */
88 static int afs_proc_cells_write(struct file *file, char *buf, size_t size)
89 {
90 struct seq_file *m = file->private_data;
91 struct afs_net *net = afs_seq2net(m);
92 char *name, *args;
93 int ret;
94
95 /* trim to first NL */
96 name = memchr(buf, '\n', size);
97 if (name)
98 *name = 0;
99
100 /* split into command, name and argslist */
101 name = strchr(buf, ' ');
102 if (!name)
103 goto inval;
104 do {
105 *name++ = 0;
106 } while(*name == ' ');
107 if (!*name)
108 goto inval;
109
110 args = strchr(name, ' ');
111 if (args) {
112 do {
113 *args++ = 0;
114 } while(*args == ' ');
115 if (!*args)
116 goto inval;
117 }
118
119 /* determine command to perform */
120 _debug("cmd=%s name=%s args=%s", buf, name, args);
121
122 if (strcmp(buf, "add") == 0) {
123 struct afs_cell *cell;
124
125 cell = afs_lookup_cell(net, name, strlen(name), args, true);
126 if (IS_ERR(cell)) {
127 ret = PTR_ERR(cell);
128 goto done;
129 }
130
131 if (test_and_set_bit(AFS_CELL_FL_NO_GC, &cell->flags))
132 afs_unuse_cell(net, cell, afs_cell_trace_unuse_no_pin);
133 } else {
134 goto inval;
135 }
136
137 ret = 0;
138
139 done:
140 _leave(" = %d", ret);
141 return ret;
142
143 inval:
144 ret = -EINVAL;
145 printk("kAFS: Invalid Command on /proc/fs/afs/cells file\n");
146 goto done;
147 }
148
149 /*
150 * Display the name of the current workstation cell.
151 */
152 static int afs_proc_rootcell_show(struct seq_file *m, void *v)
153 {
154 struct afs_cell *cell;
155 struct afs_net *net;
156
157 net = afs_seq2net_single(m);
158 down_read(&net->cells_lock);
159 cell = net->ws_cell;
160 if (cell)
161 seq_printf(m, "%s\n", cell->name);
162 up_read(&net->cells_lock);
163 return 0;
164 }
165
166 /*
167 * Set the current workstation cell and optionally supply its list of volume
168 * location servers.
169 *
170 * echo "cell.name:192.168.231.14" >/proc/fs/afs/rootcell
171 */
172 static int afs_proc_rootcell_write(struct file *file, char *buf, size_t size)
173 {
174 struct seq_file *m = file->private_data;
175 struct afs_net *net = afs_seq2net_single(m);
176 char *s;
177 int ret;
178
179 ret = -EINVAL;
180 if (buf[0] == '.')
181 goto out;
182 if (memchr(buf, '/', size))
183 goto out;
184
185 /* trim to first NL */
186 s = memchr(buf, '\n', size);
187 if (s)
188 *s = 0;
189
190 /* determine command to perform */
191 _debug("rootcell=%s", buf);
192
193 ret = afs_cell_init(net, buf);
194
195 out:
196 _leave(" = %d", ret);
197 return ret;
198 }
199
200 static const char afs_vol_types[3][3] = {
201 [AFSVL_RWVOL] = "RW",
202 [AFSVL_ROVOL] = "RO",
203 [AFSVL_BACKVOL] = "BK",
204 };
205
206 /*
207 * Display the list of volumes known to a cell.
208 */
209 static int afs_proc_cell_volumes_show(struct seq_file *m, void *v)
210 {
211 struct afs_volume *vol = hlist_entry(v, struct afs_volume, proc_link);
212
213 /* Display header on line 1 */
214 if (v == SEQ_START_TOKEN) {
215 seq_puts(m, "USE VID TY NAME\n");
216 return 0;
217 }
218
219 seq_printf(m, "%3d %08llx %s %s\n",
220 refcount_read(&vol->ref), vol->vid,
221 afs_vol_types[vol->type],
222 vol->name);
223
224 return 0;
225 }
226
227 static void *afs_proc_cell_volumes_start(struct seq_file *m, loff_t *_pos)
228 __acquires(cell->proc_lock)
229 {
230 struct afs_cell *cell = pde_data(file_inode(m->file));
231
232 rcu_read_lock();
233 return seq_hlist_start_head_rcu(&cell->proc_volumes, *_pos);
234 }
235
236 static void *afs_proc_cell_volumes_next(struct seq_file *m, void *v,
237 loff_t *_pos)
238 {
239 struct afs_cell *cell = pde_data(file_inode(m->file));
240
241 return seq_hlist_next_rcu(v, &cell->proc_volumes, _pos);
242 }
243
244 static void afs_proc_cell_volumes_stop(struct seq_file *m, void *v)
245 __releases(cell->proc_lock)
246 {
247 rcu_read_unlock();
248 }
249
250 static const struct seq_operations afs_proc_cell_volumes_ops = {
251 .start = afs_proc_cell_volumes_start,
252 .next = afs_proc_cell_volumes_next,
253 .stop = afs_proc_cell_volumes_stop,
254 .show = afs_proc_cell_volumes_show,
255 };
256
257 static const char *const dns_record_sources[NR__dns_record_source + 1] = {
258 [DNS_RECORD_UNAVAILABLE] = "unav",
259 [DNS_RECORD_FROM_CONFIG] = "cfg",
260 [DNS_RECORD_FROM_DNS_A] = "A",
261 [DNS_RECORD_FROM_DNS_AFSDB] = "AFSDB",
262 [DNS_RECORD_FROM_DNS_SRV] = "SRV",
263 [DNS_RECORD_FROM_NSS] = "nss",
264 [NR__dns_record_source] = "[weird]"
265 };
266
267 static const char *const dns_lookup_statuses[NR__dns_lookup_status + 1] = {
268 [DNS_LOOKUP_NOT_DONE] = "no-lookup",
269 [DNS_LOOKUP_GOOD] = "good",
270 [DNS_LOOKUP_GOOD_WITH_BAD] = "good/bad",
271 [DNS_LOOKUP_BAD] = "bad",
272 [DNS_LOOKUP_GOT_NOT_FOUND] = "not-found",
273 [DNS_LOOKUP_GOT_LOCAL_FAILURE] = "local-failure",
274 [DNS_LOOKUP_GOT_TEMP_FAILURE] = "temp-failure",
275 [DNS_LOOKUP_GOT_NS_FAILURE] = "ns-failure",
276 [NR__dns_lookup_status] = "[weird]"
277 };
278
279 /*
280 * Display the list of Volume Location servers we're using for a cell.
281 */
282 static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v)
283 {
284 const struct afs_vl_seq_net_private *priv = m->private;
285 const struct afs_vlserver_list *vllist = priv->vllist;
286 const struct afs_vlserver_entry *entry;
287 const struct afs_vlserver *vlserver;
288 const struct afs_addr_list *alist;
289 int i;
290
291 if (v == SEQ_START_TOKEN) {
292 seq_printf(m, "# source %s, status %s\n",
293 dns_record_sources[vllist ? vllist->source : 0],
294 dns_lookup_statuses[vllist ? vllist->status : 0]);
295 return 0;
296 }
297
298 entry = v;
299 vlserver = entry->server;
300 alist = rcu_dereference(vlserver->addresses);
301
302 seq_printf(m, "%s [p=%hu w=%hu s=%s,%s]:\n",
303 vlserver->name, entry->priority, entry->weight,
304 dns_record_sources[alist ? alist->source : entry->source],
305 dns_lookup_statuses[alist ? alist->status : entry->status]);
306 if (alist) {
307 for (i = 0; i < alist->nr_addrs; i++)
308 seq_printf(m, " %c %pISpc\n",
309 alist->preferred == i ? '>' : '-',
310 &alist->addrs[i].transport);
311 }
312 seq_printf(m, " info: fl=%lx rtt=%d\n", vlserver->flags, vlserver->rtt);
313 seq_printf(m, " probe: fl=%x e=%d ac=%d out=%d\n",
314 vlserver->probe.flags, vlserver->probe.error,
315 vlserver->probe.abort_code,
316 atomic_read(&vlserver->probe_outstanding));
317 return 0;
318 }
319
320 static void *afs_proc_cell_vlservers_start(struct seq_file *m, loff_t *_pos)
321 __acquires(rcu)
322 {
323 struct afs_vl_seq_net_private *priv = m->private;
324 struct afs_vlserver_list *vllist;
325 struct afs_cell *cell = pde_data(file_inode(m->file));
326 loff_t pos = *_pos;
327
328 rcu_read_lock();
329
330 vllist = rcu_dereference(cell->vl_servers);
331 priv->vllist = vllist;
332
333 if (pos < 0)
334 *_pos = pos = 0;
335 if (pos == 0)
336 return SEQ_START_TOKEN;
337
338 if (pos - 1 >= vllist->nr_servers)
339 return NULL;
340
341 return &vllist->servers[pos - 1];
342 }
343
344 static void *afs_proc_cell_vlservers_next(struct seq_file *m, void *v,
345 loff_t *_pos)
346 {
347 struct afs_vl_seq_net_private *priv = m->private;
348 struct afs_vlserver_list *vllist = priv->vllist;
349 loff_t pos;
350
351 pos = *_pos;
352 pos++;
353 *_pos = pos;
354 if (!vllist || pos - 1 >= vllist->nr_servers)
355 return NULL;
356
357 return &vllist->servers[pos - 1];
358 }
359
360 static void afs_proc_cell_vlservers_stop(struct seq_file *m, void *v)
361 __releases(rcu)
362 {
363 rcu_read_unlock();
364 }
365
366 static const struct seq_operations afs_proc_cell_vlservers_ops = {
367 .start = afs_proc_cell_vlservers_start,
368 .next = afs_proc_cell_vlservers_next,
369 .stop = afs_proc_cell_vlservers_stop,
370 .show = afs_proc_cell_vlservers_show,
371 };
372
373 /*
374 * Display the list of fileservers we're using within a namespace.
375 */
376 static int afs_proc_servers_show(struct seq_file *m, void *v)
377 {
378 struct afs_server *server;
379 struct afs_addr_list *alist;
380 int i;
381
382 if (v == SEQ_START_TOKEN) {
383 seq_puts(m, "UUID REF ACT\n");
384 return 0;
385 }
386
387 server = list_entry(v, struct afs_server, proc_link);
388 alist = rcu_dereference(server->addresses);
389 seq_printf(m, "%pU %3d %3d\n",
390 &server->uuid,
391 refcount_read(&server->ref),
392 atomic_read(&server->active));
393 seq_printf(m, " - info: fl=%lx rtt=%u brk=%x\n",
394 server->flags, server->rtt, server->cb_s_break);
395 seq_printf(m, " - probe: last=%d out=%d\n",
396 (int)(jiffies - server->probed_at) / HZ,
397 atomic_read(&server->probe_outstanding));
398 seq_printf(m, " - ALIST v=%u rsp=%lx f=%lx\n",
399 alist->version, alist->responded, alist->failed);
400 for (i = 0; i < alist->nr_addrs; i++)
401 seq_printf(m, " [%x] %pISpc%s\n",
402 i, &alist->addrs[i].transport,
403 alist->preferred == i ? "*" : "");
404 return 0;
405 }
406
407 static void *afs_proc_servers_start(struct seq_file *m, loff_t *_pos)
408 __acquires(rcu)
409 {
410 rcu_read_lock();
411 return seq_hlist_start_head_rcu(&afs_seq2net(m)->fs_proc, *_pos);
412 }
413
414 static void *afs_proc_servers_next(struct seq_file *m, void *v, loff_t *_pos)
415 {
416 return seq_hlist_next_rcu(v, &afs_seq2net(m)->fs_proc, _pos);
417 }
418
419 static void afs_proc_servers_stop(struct seq_file *m, void *v)
420 __releases(rcu)
421 {
422 rcu_read_unlock();
423 }
424
425 static const struct seq_operations afs_proc_servers_ops = {
426 .start = afs_proc_servers_start,
427 .next = afs_proc_servers_next,
428 .stop = afs_proc_servers_stop,
429 .show = afs_proc_servers_show,
430 };
431
432 /*
433 * Display the list of strings that may be substituted for the @sys pathname
434 * macro.
435 */
436 static int afs_proc_sysname_show(struct seq_file *m, void *v)
437 {
438 struct afs_net *net = afs_seq2net(m);
439 struct afs_sysnames *sysnames = net->sysnames;
440 unsigned int i = (unsigned long)v - 1;
441
442 if (i < sysnames->nr)
443 seq_printf(m, "%s\n", sysnames->subs[i]);
444 return 0;
445 }
446
447 static void *afs_proc_sysname_start(struct seq_file *m, loff_t *pos)
448 __acquires(&net->sysnames_lock)
449 {
450 struct afs_net *net = afs_seq2net(m);
451 struct afs_sysnames *names;
452
453 read_lock(&net->sysnames_lock);
454
455 names = net->sysnames;
456 if (*pos >= names->nr)
457 return NULL;
458 return (void *)(unsigned long)(*pos + 1);
459 }
460
461 static void *afs_proc_sysname_next(struct seq_file *m, void *v, loff_t *pos)
462 {
463 struct afs_net *net = afs_seq2net(m);
464 struct afs_sysnames *names = net->sysnames;
465
466 *pos += 1;
467 if (*pos >= names->nr)
468 return NULL;
469 return (void *)(unsigned long)(*pos + 1);
470 }
471
472 static void afs_proc_sysname_stop(struct seq_file *m, void *v)
473 __releases(&net->sysnames_lock)
474 {
475 struct afs_net *net = afs_seq2net(m);
476
477 read_unlock(&net->sysnames_lock);
478 }
479
480 static const struct seq_operations afs_proc_sysname_ops = {
481 .start = afs_proc_sysname_start,
482 .next = afs_proc_sysname_next,
483 .stop = afs_proc_sysname_stop,
484 .show = afs_proc_sysname_show,
485 };
486
487 /*
488 * Allow the @sys substitution to be configured.
489 */
490 static int afs_proc_sysname_write(struct file *file, char *buf, size_t size)
491 {
492 struct afs_sysnames *sysnames, *kill;
493 struct seq_file *m = file->private_data;
494 struct afs_net *net = afs_seq2net(m);
495 char *s, *p, *sub;
496 int ret, len;
497
498 sysnames = kzalloc(sizeof(*sysnames), GFP_KERNEL);
499 if (!sysnames)
500 return -ENOMEM;
501 refcount_set(&sysnames->usage, 1);
502 kill = sysnames;
503
504 p = buf;
505 while ((s = strsep(&p, " \t\n"))) {
506 len = strlen(s);
507 if (len == 0)
508 continue;
509 ret = -ENAMETOOLONG;
510 if (len >= AFSNAMEMAX)
511 goto error;
512
513 if (len >= 4 &&
514 s[len - 4] == '@' &&
515 s[len - 3] == 's' &&
516 s[len - 2] == 'y' &&
517 s[len - 1] == 's')
518 /* Protect against recursion */
519 goto invalid;
520
521 if (s[0] == '.' &&
522 (len < 2 || (len == 2 && s[1] == '.')))
523 goto invalid;
524
525 if (memchr(s, '/', len))
526 goto invalid;
527
528 ret = -EFBIG;
529 if (sysnames->nr >= AFS_NR_SYSNAME)
530 goto out;
531
532 if (strcmp(s, afs_init_sysname) == 0) {
533 sub = (char *)afs_init_sysname;
534 } else {
535 ret = -ENOMEM;
536 sub = kmemdup(s, len + 1, GFP_KERNEL);
537 if (!sub)
538 goto out;
539 }
540
541 sysnames->subs[sysnames->nr] = sub;
542 sysnames->nr++;
543 }
544
545 if (sysnames->nr == 0) {
546 sysnames->subs[0] = sysnames->blank;
547 sysnames->nr++;
548 }
549
550 write_lock(&net->sysnames_lock);
551 kill = net->sysnames;
552 net->sysnames = sysnames;
553 write_unlock(&net->sysnames_lock);
554 ret = 0;
555 out:
556 afs_put_sysnames(kill);
557 return ret;
558
559 invalid:
560 ret = -EINVAL;
561 error:
562 goto out;
563 }
564
565 void afs_put_sysnames(struct afs_sysnames *sysnames)
566 {
567 int i;
568
569 if (sysnames && refcount_dec_and_test(&sysnames->usage)) {
570 for (i = 0; i < sysnames->nr; i++)
571 if (sysnames->subs[i] != afs_init_sysname &&
572 sysnames->subs[i] != sysnames->blank)
573 kfree(sysnames->subs[i]);
574 kfree(sysnames);
575 }
576 }
577
578 /*
579 * Display general per-net namespace statistics
580 */
581 static int afs_proc_stats_show(struct seq_file *m, void *v)
582 {
583 struct afs_net *net = afs_seq2net_single(m);
584
585 seq_puts(m, "kAFS statistics\n");
586
587 seq_printf(m, "dir-mgmt: look=%u reval=%u inval=%u relpg=%u\n",
588 atomic_read(&net->n_lookup),
589 atomic_read(&net->n_reval),
590 atomic_read(&net->n_inval),
591 atomic_read(&net->n_relpg));
592
593 seq_printf(m, "dir-data: rdpg=%u\n",
594 atomic_read(&net->n_read_dir));
595
596 seq_printf(m, "dir-edit: cr=%u rm=%u\n",
597 atomic_read(&net->n_dir_cr),
598 atomic_read(&net->n_dir_rm));
599
600 seq_printf(m, "file-rd : n=%u nb=%lu\n",
601 atomic_read(&net->n_fetches),
602 atomic_long_read(&net->n_fetch_bytes));
603 seq_printf(m, "file-wr : n=%u nb=%lu\n",
604 atomic_read(&net->n_stores),
605 atomic_long_read(&net->n_store_bytes));
606 return 0;
607 }
608
609 /*
610 * initialise /proc/fs/afs/<cell>/
611 */
612 int afs_proc_cell_setup(struct afs_cell *cell)
613 {
614 struct proc_dir_entry *dir;
615 struct afs_net *net = cell->net;
616
617 _enter("%p{%s},%p", cell, cell->name, net->proc_afs);
618
619 dir = proc_net_mkdir(net->net, cell->name, net->proc_afs);
620 if (!dir)
621 goto error_dir;
622
623 if (!proc_create_net_data("vlservers", 0444, dir,
624 &afs_proc_cell_vlservers_ops,
625 sizeof(struct afs_vl_seq_net_private),
626 cell) ||
627 !proc_create_net_data("volumes", 0444, dir,
628 &afs_proc_cell_volumes_ops,
629 sizeof(struct seq_net_private),
630 cell))
631 goto error_tree;
632
633 _leave(" = 0");
634 return 0;
635
636 error_tree:
637 remove_proc_subtree(cell->name, net->proc_afs);
638 error_dir:
639 _leave(" = -ENOMEM");
640 return -ENOMEM;
641 }
642
643 /*
644 * remove /proc/fs/afs/<cell>/
645 */
646 void afs_proc_cell_remove(struct afs_cell *cell)
647 {
648 struct afs_net *net = cell->net;
649
650 _enter("");
651 remove_proc_subtree(cell->name, net->proc_afs);
652 _leave("");
653 }
654
655 /*
656 * initialise the /proc/fs/afs/ directory
657 */
658 int afs_proc_init(struct afs_net *net)
659 {
660 struct proc_dir_entry *p;
661
662 _enter("");
663
664 p = proc_net_mkdir(net->net, "afs", net->net->proc_net);
665 if (!p)
666 goto error_dir;
667
668 if (!proc_create_net_data_write("cells", 0644, p,
669 &afs_proc_cells_ops,
670 afs_proc_cells_write,
671 sizeof(struct seq_net_private),
672 NULL) ||
673 !proc_create_net_single_write("rootcell", 0644, p,
674 afs_proc_rootcell_show,
675 afs_proc_rootcell_write,
676 NULL) ||
677 !proc_create_net("servers", 0444, p, &afs_proc_servers_ops,
678 sizeof(struct seq_net_private)) ||
679 !proc_create_net_single("stats", 0444, p, afs_proc_stats_show, NULL) ||
680 !proc_create_net_data_write("sysname", 0644, p,
681 &afs_proc_sysname_ops,
682 afs_proc_sysname_write,
683 sizeof(struct seq_net_private),
684 NULL))
685 goto error_tree;
686
687 net->proc_afs = p;
688 _leave(" = 0");
689 return 0;
690
691 error_tree:
692 proc_remove(p);
693 error_dir:
694 _leave(" = -ENOMEM");
695 return -ENOMEM;
696 }
697
698 /*
699 * clean up the /proc/fs/afs/ directory
700 */
701 void afs_proc_cleanup(struct afs_net *net)
702 {
703 proc_remove(net->proc_afs);
704 net->proc_afs = NULL;
705 }
706
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