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[PATCH] proc: Simplify the ownership rules for /proc
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1 /*
2 * linux/fs/proc/base.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 *
6 * proc base directory handling functions
7 *
8 * 1999, Al Viro. Rewritten. Now it covers the whole per-process part.
9 * Instead of using magical inumbers to determine the kind of object
10 * we allocate and fill in-core inodes upon lookup. They don't even
11 * go into icache. We cache the reference to task_struct upon lookup too.
12 * Eventually it should become a filesystem in its own. We don't use the
13 * rest of procfs anymore.
14 *
15 *
16 * Changelog:
17 * 17-Jan-2005
18 * Allan Bezerra
19 * Bruna Moreira <bruna.moreira@indt.org.br>
20 * Edjard Mota <edjard.mota@indt.org.br>
21 * Ilias Biris <ilias.biris@indt.org.br>
22 * Mauricio Lin <mauricio.lin@indt.org.br>
23 *
24 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT
25 *
26 * A new process specific entry (smaps) included in /proc. It shows the
27 * size of rss for each memory area. The maps entry lacks information
28 * about physical memory size (rss) for each mapped file, i.e.,
29 * rss information for executables and library files.
30 * This additional information is useful for any tools that need to know
31 * about physical memory consumption for a process specific library.
32 *
33 * Changelog:
34 * 21-Feb-2005
35 * Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT
36 * Pud inclusion in the page table walking.
37 *
38 * ChangeLog:
39 * 10-Mar-2005
40 * 10LE Instituto Nokia de Tecnologia - INdT:
41 * A better way to walks through the page table as suggested by Hugh Dickins.
42 *
43 * Simo Piiroinen <simo.piiroinen@nokia.com>:
44 * Smaps information related to shared, private, clean and dirty pages.
45 *
46 * Paul Mundt <paul.mundt@nokia.com>:
47 * Overall revision about smaps.
48 */
49
50 #include <asm/uaccess.h>
51
52 #include <linux/config.h>
53 #include <linux/errno.h>
54 #include <linux/time.h>
55 #include <linux/proc_fs.h>
56 #include <linux/stat.h>
57 #include <linux/init.h>
58 #include <linux/capability.h>
59 #include <linux/file.h>
60 #include <linux/string.h>
61 #include <linux/seq_file.h>
62 #include <linux/namei.h>
63 #include <linux/namespace.h>
64 #include <linux/mm.h>
65 #include <linux/smp_lock.h>
66 #include <linux/rcupdate.h>
67 #include <linux/kallsyms.h>
68 #include <linux/mount.h>
69 #include <linux/security.h>
70 #include <linux/ptrace.h>
71 #include <linux/seccomp.h>
72 #include <linux/cpuset.h>
73 #include <linux/audit.h>
74 #include <linux/poll.h>
75 #include "internal.h"
76
77 /*
78 * For hysterical raisins we keep the same inumbers as in the old procfs.
79 * Feel free to change the macro below - just keep the range distinct from
80 * inumbers of the rest of procfs (currently those are in 0x0000--0xffff).
81 * As soon as we'll get a separate superblock we will be able to forget
82 * about magical ranges too.
83 */
84
85 #define fake_ino(pid,ino) (((pid)<<16)|(ino))
86
87 enum pid_directory_inos {
88 PROC_TGID_INO = 2,
89 PROC_TGID_TASK,
90 PROC_TGID_STATUS,
91 PROC_TGID_MEM,
92 #ifdef CONFIG_SECCOMP
93 PROC_TGID_SECCOMP,
94 #endif
95 PROC_TGID_CWD,
96 PROC_TGID_ROOT,
97 PROC_TGID_EXE,
98 PROC_TGID_FD,
99 PROC_TGID_ENVIRON,
100 PROC_TGID_AUXV,
101 PROC_TGID_CMDLINE,
102 PROC_TGID_STAT,
103 PROC_TGID_STATM,
104 PROC_TGID_MAPS,
105 PROC_TGID_NUMA_MAPS,
106 PROC_TGID_MOUNTS,
107 PROC_TGID_MOUNTSTATS,
108 PROC_TGID_WCHAN,
109 #ifdef CONFIG_MMU
110 PROC_TGID_SMAPS,
111 #endif
112 #ifdef CONFIG_SCHEDSTATS
113 PROC_TGID_SCHEDSTAT,
114 #endif
115 #ifdef CONFIG_CPUSETS
116 PROC_TGID_CPUSET,
117 #endif
118 #ifdef CONFIG_SECURITY
119 PROC_TGID_ATTR,
120 PROC_TGID_ATTR_CURRENT,
121 PROC_TGID_ATTR_PREV,
122 PROC_TGID_ATTR_EXEC,
123 PROC_TGID_ATTR_FSCREATE,
124 PROC_TGID_ATTR_KEYCREATE,
125 #endif
126 #ifdef CONFIG_AUDITSYSCALL
127 PROC_TGID_LOGINUID,
128 #endif
129 PROC_TGID_OOM_SCORE,
130 PROC_TGID_OOM_ADJUST,
131 PROC_TID_INO,
132 PROC_TID_STATUS,
133 PROC_TID_MEM,
134 #ifdef CONFIG_SECCOMP
135 PROC_TID_SECCOMP,
136 #endif
137 PROC_TID_CWD,
138 PROC_TID_ROOT,
139 PROC_TID_EXE,
140 PROC_TID_FD,
141 PROC_TID_ENVIRON,
142 PROC_TID_AUXV,
143 PROC_TID_CMDLINE,
144 PROC_TID_STAT,
145 PROC_TID_STATM,
146 PROC_TID_MAPS,
147 PROC_TID_NUMA_MAPS,
148 PROC_TID_MOUNTS,
149 PROC_TID_MOUNTSTATS,
150 PROC_TID_WCHAN,
151 #ifdef CONFIG_MMU
152 PROC_TID_SMAPS,
153 #endif
154 #ifdef CONFIG_SCHEDSTATS
155 PROC_TID_SCHEDSTAT,
156 #endif
157 #ifdef CONFIG_CPUSETS
158 PROC_TID_CPUSET,
159 #endif
160 #ifdef CONFIG_SECURITY
161 PROC_TID_ATTR,
162 PROC_TID_ATTR_CURRENT,
163 PROC_TID_ATTR_PREV,
164 PROC_TID_ATTR_EXEC,
165 PROC_TID_ATTR_FSCREATE,
166 PROC_TID_ATTR_KEYCREATE,
167 #endif
168 #ifdef CONFIG_AUDITSYSCALL
169 PROC_TID_LOGINUID,
170 #endif
171 PROC_TID_OOM_SCORE,
172 PROC_TID_OOM_ADJUST,
173
174 /* Add new entries before this */
175 PROC_TID_FD_DIR = 0x8000, /* 0x8000-0xffff */
176 };
177
178 struct pid_entry {
179 int type;
180 int len;
181 char *name;
182 mode_t mode;
183 };
184
185 #define E(type,name,mode) {(type),sizeof(name)-1,(name),(mode)}
186
187 static struct pid_entry tgid_base_stuff[] = {
188 E(PROC_TGID_TASK, "task", S_IFDIR|S_IRUGO|S_IXUGO),
189 E(PROC_TGID_FD, "fd", S_IFDIR|S_IRUSR|S_IXUSR),
190 E(PROC_TGID_ENVIRON, "environ", S_IFREG|S_IRUSR),
191 E(PROC_TGID_AUXV, "auxv", S_IFREG|S_IRUSR),
192 E(PROC_TGID_STATUS, "status", S_IFREG|S_IRUGO),
193 E(PROC_TGID_CMDLINE, "cmdline", S_IFREG|S_IRUGO),
194 E(PROC_TGID_STAT, "stat", S_IFREG|S_IRUGO),
195 E(PROC_TGID_STATM, "statm", S_IFREG|S_IRUGO),
196 E(PROC_TGID_MAPS, "maps", S_IFREG|S_IRUGO),
197 #ifdef CONFIG_NUMA
198 E(PROC_TGID_NUMA_MAPS, "numa_maps", S_IFREG|S_IRUGO),
199 #endif
200 E(PROC_TGID_MEM, "mem", S_IFREG|S_IRUSR|S_IWUSR),
201 #ifdef CONFIG_SECCOMP
202 E(PROC_TGID_SECCOMP, "seccomp", S_IFREG|S_IRUSR|S_IWUSR),
203 #endif
204 E(PROC_TGID_CWD, "cwd", S_IFLNK|S_IRWXUGO),
205 E(PROC_TGID_ROOT, "root", S_IFLNK|S_IRWXUGO),
206 E(PROC_TGID_EXE, "exe", S_IFLNK|S_IRWXUGO),
207 E(PROC_TGID_MOUNTS, "mounts", S_IFREG|S_IRUGO),
208 E(PROC_TGID_MOUNTSTATS, "mountstats", S_IFREG|S_IRUSR),
209 #ifdef CONFIG_MMU
210 E(PROC_TGID_SMAPS, "smaps", S_IFREG|S_IRUGO),
211 #endif
212 #ifdef CONFIG_SECURITY
213 E(PROC_TGID_ATTR, "attr", S_IFDIR|S_IRUGO|S_IXUGO),
214 #endif
215 #ifdef CONFIG_KALLSYMS
216 E(PROC_TGID_WCHAN, "wchan", S_IFREG|S_IRUGO),
217 #endif
218 #ifdef CONFIG_SCHEDSTATS
219 E(PROC_TGID_SCHEDSTAT, "schedstat", S_IFREG|S_IRUGO),
220 #endif
221 #ifdef CONFIG_CPUSETS
222 E(PROC_TGID_CPUSET, "cpuset", S_IFREG|S_IRUGO),
223 #endif
224 E(PROC_TGID_OOM_SCORE, "oom_score",S_IFREG|S_IRUGO),
225 E(PROC_TGID_OOM_ADJUST,"oom_adj", S_IFREG|S_IRUGO|S_IWUSR),
226 #ifdef CONFIG_AUDITSYSCALL
227 E(PROC_TGID_LOGINUID, "loginuid", S_IFREG|S_IWUSR|S_IRUGO),
228 #endif
229 {0,0,NULL,0}
230 };
231 static struct pid_entry tid_base_stuff[] = {
232 E(PROC_TID_FD, "fd", S_IFDIR|S_IRUSR|S_IXUSR),
233 E(PROC_TID_ENVIRON, "environ", S_IFREG|S_IRUSR),
234 E(PROC_TID_AUXV, "auxv", S_IFREG|S_IRUSR),
235 E(PROC_TID_STATUS, "status", S_IFREG|S_IRUGO),
236 E(PROC_TID_CMDLINE, "cmdline", S_IFREG|S_IRUGO),
237 E(PROC_TID_STAT, "stat", S_IFREG|S_IRUGO),
238 E(PROC_TID_STATM, "statm", S_IFREG|S_IRUGO),
239 E(PROC_TID_MAPS, "maps", S_IFREG|S_IRUGO),
240 #ifdef CONFIG_NUMA
241 E(PROC_TID_NUMA_MAPS, "numa_maps", S_IFREG|S_IRUGO),
242 #endif
243 E(PROC_TID_MEM, "mem", S_IFREG|S_IRUSR|S_IWUSR),
244 #ifdef CONFIG_SECCOMP
245 E(PROC_TID_SECCOMP, "seccomp", S_IFREG|S_IRUSR|S_IWUSR),
246 #endif
247 E(PROC_TID_CWD, "cwd", S_IFLNK|S_IRWXUGO),
248 E(PROC_TID_ROOT, "root", S_IFLNK|S_IRWXUGO),
249 E(PROC_TID_EXE, "exe", S_IFLNK|S_IRWXUGO),
250 E(PROC_TID_MOUNTS, "mounts", S_IFREG|S_IRUGO),
251 #ifdef CONFIG_MMU
252 E(PROC_TID_SMAPS, "smaps", S_IFREG|S_IRUGO),
253 #endif
254 #ifdef CONFIG_SECURITY
255 E(PROC_TID_ATTR, "attr", S_IFDIR|S_IRUGO|S_IXUGO),
256 #endif
257 #ifdef CONFIG_KALLSYMS
258 E(PROC_TID_WCHAN, "wchan", S_IFREG|S_IRUGO),
259 #endif
260 #ifdef CONFIG_SCHEDSTATS
261 E(PROC_TID_SCHEDSTAT, "schedstat",S_IFREG|S_IRUGO),
262 #endif
263 #ifdef CONFIG_CPUSETS
264 E(PROC_TID_CPUSET, "cpuset", S_IFREG|S_IRUGO),
265 #endif
266 E(PROC_TID_OOM_SCORE, "oom_score",S_IFREG|S_IRUGO),
267 E(PROC_TID_OOM_ADJUST, "oom_adj", S_IFREG|S_IRUGO|S_IWUSR),
268 #ifdef CONFIG_AUDITSYSCALL
269 E(PROC_TID_LOGINUID, "loginuid", S_IFREG|S_IWUSR|S_IRUGO),
270 #endif
271 {0,0,NULL,0}
272 };
273
274 #ifdef CONFIG_SECURITY
275 static struct pid_entry tgid_attr_stuff[] = {
276 E(PROC_TGID_ATTR_CURRENT, "current", S_IFREG|S_IRUGO|S_IWUGO),
277 E(PROC_TGID_ATTR_PREV, "prev", S_IFREG|S_IRUGO),
278 E(PROC_TGID_ATTR_EXEC, "exec", S_IFREG|S_IRUGO|S_IWUGO),
279 E(PROC_TGID_ATTR_FSCREATE, "fscreate", S_IFREG|S_IRUGO|S_IWUGO),
280 E(PROC_TGID_ATTR_KEYCREATE, "keycreate", S_IFREG|S_IRUGO|S_IWUGO),
281 {0,0,NULL,0}
282 };
283 static struct pid_entry tid_attr_stuff[] = {
284 E(PROC_TID_ATTR_CURRENT, "current", S_IFREG|S_IRUGO|S_IWUGO),
285 E(PROC_TID_ATTR_PREV, "prev", S_IFREG|S_IRUGO),
286 E(PROC_TID_ATTR_EXEC, "exec", S_IFREG|S_IRUGO|S_IWUGO),
287 E(PROC_TID_ATTR_FSCREATE, "fscreate", S_IFREG|S_IRUGO|S_IWUGO),
288 E(PROC_TID_ATTR_KEYCREATE, "keycreate", S_IFREG|S_IRUGO|S_IWUGO),
289 {0,0,NULL,0}
290 };
291 #endif
292
293 #undef E
294
295 static int proc_fd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt)
296 {
297 struct task_struct *task = proc_task(inode);
298 struct files_struct *files;
299 struct file *file;
300 int fd = proc_type(inode) - PROC_TID_FD_DIR;
301
302 files = get_files_struct(task);
303 if (files) {
304 /*
305 * We are not taking a ref to the file structure, so we must
306 * hold ->file_lock.
307 */
308 spin_lock(&files->file_lock);
309 file = fcheck_files(files, fd);
310 if (file) {
311 *mnt = mntget(file->f_vfsmnt);
312 *dentry = dget(file->f_dentry);
313 spin_unlock(&files->file_lock);
314 put_files_struct(files);
315 return 0;
316 }
317 spin_unlock(&files->file_lock);
318 put_files_struct(files);
319 }
320 return -ENOENT;
321 }
322
323 static struct fs_struct *get_fs_struct(struct task_struct *task)
324 {
325 struct fs_struct *fs;
326 task_lock(task);
327 fs = task->fs;
328 if(fs)
329 atomic_inc(&fs->count);
330 task_unlock(task);
331 return fs;
332 }
333
334 static int proc_cwd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt)
335 {
336 struct fs_struct *fs = get_fs_struct(proc_task(inode));
337 int result = -ENOENT;
338 if (fs) {
339 read_lock(&fs->lock);
340 *mnt = mntget(fs->pwdmnt);
341 *dentry = dget(fs->pwd);
342 read_unlock(&fs->lock);
343 result = 0;
344 put_fs_struct(fs);
345 }
346 return result;
347 }
348
349 static int proc_root_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt)
350 {
351 struct fs_struct *fs = get_fs_struct(proc_task(inode));
352 int result = -ENOENT;
353 if (fs) {
354 read_lock(&fs->lock);
355 *mnt = mntget(fs->rootmnt);
356 *dentry = dget(fs->root);
357 read_unlock(&fs->lock);
358 result = 0;
359 put_fs_struct(fs);
360 }
361 return result;
362 }
363
364
365 /* Same as proc_root_link, but this addionally tries to get fs from other
366 * threads in the group */
367 static int proc_task_root_link(struct inode *inode, struct dentry **dentry,
368 struct vfsmount **mnt)
369 {
370 struct fs_struct *fs;
371 int result = -ENOENT;
372 struct task_struct *leader = proc_task(inode);
373
374 task_lock(leader);
375 fs = leader->fs;
376 if (fs) {
377 atomic_inc(&fs->count);
378 task_unlock(leader);
379 } else {
380 /* Try to get fs from other threads */
381 task_unlock(leader);
382 read_lock(&tasklist_lock);
383 if (pid_alive(leader)) {
384 struct task_struct *task = leader;
385
386 while ((task = next_thread(task)) != leader) {
387 task_lock(task);
388 fs = task->fs;
389 if (fs) {
390 atomic_inc(&fs->count);
391 task_unlock(task);
392 break;
393 }
394 task_unlock(task);
395 }
396 }
397 read_unlock(&tasklist_lock);
398 }
399
400 if (fs) {
401 read_lock(&fs->lock);
402 *mnt = mntget(fs->rootmnt);
403 *dentry = dget(fs->root);
404 read_unlock(&fs->lock);
405 result = 0;
406 put_fs_struct(fs);
407 }
408 return result;
409 }
410
411
412 #define MAY_PTRACE(task) \
413 (task == current || \
414 (task->parent == current && \
415 (task->ptrace & PT_PTRACED) && \
416 (task->state == TASK_STOPPED || task->state == TASK_TRACED) && \
417 security_ptrace(current,task) == 0))
418
419 static int proc_pid_environ(struct task_struct *task, char * buffer)
420 {
421 int res = 0;
422 struct mm_struct *mm = get_task_mm(task);
423 if (mm) {
424 unsigned int len = mm->env_end - mm->env_start;
425 if (len > PAGE_SIZE)
426 len = PAGE_SIZE;
427 res = access_process_vm(task, mm->env_start, buffer, len, 0);
428 if (!ptrace_may_attach(task))
429 res = -ESRCH;
430 mmput(mm);
431 }
432 return res;
433 }
434
435 static int proc_pid_cmdline(struct task_struct *task, char * buffer)
436 {
437 int res = 0;
438 unsigned int len;
439 struct mm_struct *mm = get_task_mm(task);
440 if (!mm)
441 goto out;
442 if (!mm->arg_end)
443 goto out_mm; /* Shh! No looking before we're done */
444
445 len = mm->arg_end - mm->arg_start;
446
447 if (len > PAGE_SIZE)
448 len = PAGE_SIZE;
449
450 res = access_process_vm(task, mm->arg_start, buffer, len, 0);
451
452 // If the nul at the end of args has been overwritten, then
453 // assume application is using setproctitle(3).
454 if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) {
455 len = strnlen(buffer, res);
456 if (len < res) {
457 res = len;
458 } else {
459 len = mm->env_end - mm->env_start;
460 if (len > PAGE_SIZE - res)
461 len = PAGE_SIZE - res;
462 res += access_process_vm(task, mm->env_start, buffer+res, len, 0);
463 res = strnlen(buffer, res);
464 }
465 }
466 out_mm:
467 mmput(mm);
468 out:
469 return res;
470 }
471
472 static int proc_pid_auxv(struct task_struct *task, char *buffer)
473 {
474 int res = 0;
475 struct mm_struct *mm = get_task_mm(task);
476 if (mm) {
477 unsigned int nwords = 0;
478 do
479 nwords += 2;
480 while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
481 res = nwords * sizeof(mm->saved_auxv[0]);
482 if (res > PAGE_SIZE)
483 res = PAGE_SIZE;
484 memcpy(buffer, mm->saved_auxv, res);
485 mmput(mm);
486 }
487 return res;
488 }
489
490
491 #ifdef CONFIG_KALLSYMS
492 /*
493 * Provides a wchan file via kallsyms in a proper one-value-per-file format.
494 * Returns the resolved symbol. If that fails, simply return the address.
495 */
496 static int proc_pid_wchan(struct task_struct *task, char *buffer)
497 {
498 char *modname;
499 const char *sym_name;
500 unsigned long wchan, size, offset;
501 char namebuf[KSYM_NAME_LEN+1];
502
503 wchan = get_wchan(task);
504
505 sym_name = kallsyms_lookup(wchan, &size, &offset, &modname, namebuf);
506 if (sym_name)
507 return sprintf(buffer, "%s", sym_name);
508 return sprintf(buffer, "%lu", wchan);
509 }
510 #endif /* CONFIG_KALLSYMS */
511
512 #ifdef CONFIG_SCHEDSTATS
513 /*
514 * Provides /proc/PID/schedstat
515 */
516 static int proc_pid_schedstat(struct task_struct *task, char *buffer)
517 {
518 return sprintf(buffer, "%lu %lu %lu\n",
519 task->sched_info.cpu_time,
520 task->sched_info.run_delay,
521 task->sched_info.pcnt);
522 }
523 #endif
524
525 /* The badness from the OOM killer */
526 unsigned long badness(struct task_struct *p, unsigned long uptime);
527 static int proc_oom_score(struct task_struct *task, char *buffer)
528 {
529 unsigned long points;
530 struct timespec uptime;
531
532 do_posix_clock_monotonic_gettime(&uptime);
533 points = badness(task, uptime.tv_sec);
534 return sprintf(buffer, "%lu\n", points);
535 }
536
537 /************************************************************************/
538 /* Here the fs part begins */
539 /************************************************************************/
540
541 /* permission checks */
542
543 /* If the process being read is separated by chroot from the reading process,
544 * don't let the reader access the threads.
545 *
546 * note: this does dput(root) and mntput(vfsmnt) on exit.
547 */
548 static int proc_check_chroot(struct dentry *root, struct vfsmount *vfsmnt)
549 {
550 struct dentry *de, *base;
551 struct vfsmount *our_vfsmnt, *mnt;
552 int res = 0;
553
554 read_lock(&current->fs->lock);
555 our_vfsmnt = mntget(current->fs->rootmnt);
556 base = dget(current->fs->root);
557 read_unlock(&current->fs->lock);
558
559 spin_lock(&vfsmount_lock);
560 de = root;
561 mnt = vfsmnt;
562
563 while (mnt != our_vfsmnt) {
564 if (mnt == mnt->mnt_parent)
565 goto out;
566 de = mnt->mnt_mountpoint;
567 mnt = mnt->mnt_parent;
568 }
569
570 if (!is_subdir(de, base))
571 goto out;
572 spin_unlock(&vfsmount_lock);
573
574 exit:
575 dput(base);
576 mntput(our_vfsmnt);
577 dput(root);
578 mntput(vfsmnt);
579 return res;
580 out:
581 spin_unlock(&vfsmount_lock);
582 res = -EACCES;
583 goto exit;
584 }
585
586 static int proc_check_root(struct inode *inode)
587 {
588 struct dentry *root;
589 struct vfsmount *vfsmnt;
590
591 if (proc_root_link(inode, &root, &vfsmnt)) /* Ewww... */
592 return -ENOENT;
593 return proc_check_chroot(root, vfsmnt);
594 }
595
596 static int proc_permission(struct inode *inode, int mask, struct nameidata *nd)
597 {
598 if (generic_permission(inode, mask, NULL) != 0)
599 return -EACCES;
600 return proc_check_root(inode);
601 }
602
603 static int proc_task_permission(struct inode *inode, int mask, struct nameidata *nd)
604 {
605 struct dentry *root;
606 struct vfsmount *vfsmnt;
607
608 if (generic_permission(inode, mask, NULL) != 0)
609 return -EACCES;
610
611 if (proc_task_root_link(inode, &root, &vfsmnt))
612 return -ENOENT;
613
614 return proc_check_chroot(root, vfsmnt);
615 }
616
617 extern struct seq_operations proc_pid_maps_op;
618 static int maps_open(struct inode *inode, struct file *file)
619 {
620 struct task_struct *task = proc_task(inode);
621 int ret = seq_open(file, &proc_pid_maps_op);
622 if (!ret) {
623 struct seq_file *m = file->private_data;
624 m->private = task;
625 }
626 return ret;
627 }
628
629 static struct file_operations proc_maps_operations = {
630 .open = maps_open,
631 .read = seq_read,
632 .llseek = seq_lseek,
633 .release = seq_release,
634 };
635
636 #ifdef CONFIG_NUMA
637 extern struct seq_operations proc_pid_numa_maps_op;
638 static int numa_maps_open(struct inode *inode, struct file *file)
639 {
640 struct task_struct *task = proc_task(inode);
641 int ret = seq_open(file, &proc_pid_numa_maps_op);
642 if (!ret) {
643 struct seq_file *m = file->private_data;
644 m->private = task;
645 }
646 return ret;
647 }
648
649 static struct file_operations proc_numa_maps_operations = {
650 .open = numa_maps_open,
651 .read = seq_read,
652 .llseek = seq_lseek,
653 .release = seq_release,
654 };
655 #endif
656
657 #ifdef CONFIG_MMU
658 extern struct seq_operations proc_pid_smaps_op;
659 static int smaps_open(struct inode *inode, struct file *file)
660 {
661 struct task_struct *task = proc_task(inode);
662 int ret = seq_open(file, &proc_pid_smaps_op);
663 if (!ret) {
664 struct seq_file *m = file->private_data;
665 m->private = task;
666 }
667 return ret;
668 }
669
670 static struct file_operations proc_smaps_operations = {
671 .open = smaps_open,
672 .read = seq_read,
673 .llseek = seq_lseek,
674 .release = seq_release,
675 };
676 #endif
677
678 extern struct seq_operations mounts_op;
679 struct proc_mounts {
680 struct seq_file m;
681 int event;
682 };
683
684 static int mounts_open(struct inode *inode, struct file *file)
685 {
686 struct task_struct *task = proc_task(inode);
687 struct namespace *namespace;
688 struct proc_mounts *p;
689 int ret = -EINVAL;
690
691 task_lock(task);
692 namespace = task->namespace;
693 if (namespace)
694 get_namespace(namespace);
695 task_unlock(task);
696
697 if (namespace) {
698 ret = -ENOMEM;
699 p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL);
700 if (p) {
701 file->private_data = &p->m;
702 ret = seq_open(file, &mounts_op);
703 if (!ret) {
704 p->m.private = namespace;
705 p->event = namespace->event;
706 return 0;
707 }
708 kfree(p);
709 }
710 put_namespace(namespace);
711 }
712 return ret;
713 }
714
715 static int mounts_release(struct inode *inode, struct file *file)
716 {
717 struct seq_file *m = file->private_data;
718 struct namespace *namespace = m->private;
719 put_namespace(namespace);
720 return seq_release(inode, file);
721 }
722
723 static unsigned mounts_poll(struct file *file, poll_table *wait)
724 {
725 struct proc_mounts *p = file->private_data;
726 struct namespace *ns = p->m.private;
727 unsigned res = 0;
728
729 poll_wait(file, &ns->poll, wait);
730
731 spin_lock(&vfsmount_lock);
732 if (p->event != ns->event) {
733 p->event = ns->event;
734 res = POLLERR;
735 }
736 spin_unlock(&vfsmount_lock);
737
738 return res;
739 }
740
741 static struct file_operations proc_mounts_operations = {
742 .open = mounts_open,
743 .read = seq_read,
744 .llseek = seq_lseek,
745 .release = mounts_release,
746 .poll = mounts_poll,
747 };
748
749 extern struct seq_operations mountstats_op;
750 static int mountstats_open(struct inode *inode, struct file *file)
751 {
752 struct task_struct *task = proc_task(inode);
753 int ret = seq_open(file, &mountstats_op);
754
755 if (!ret) {
756 struct seq_file *m = file->private_data;
757 struct namespace *namespace;
758 task_lock(task);
759 namespace = task->namespace;
760 if (namespace)
761 get_namespace(namespace);
762 task_unlock(task);
763
764 if (namespace)
765 m->private = namespace;
766 else {
767 seq_release(inode, file);
768 ret = -EINVAL;
769 }
770 }
771 return ret;
772 }
773
774 static struct file_operations proc_mountstats_operations = {
775 .open = mountstats_open,
776 .read = seq_read,
777 .llseek = seq_lseek,
778 .release = mounts_release,
779 };
780
781 #define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */
782
783 static ssize_t proc_info_read(struct file * file, char __user * buf,
784 size_t count, loff_t *ppos)
785 {
786 struct inode * inode = file->f_dentry->d_inode;
787 unsigned long page;
788 ssize_t length;
789 struct task_struct *task = proc_task(inode);
790
791 if (count > PROC_BLOCK_SIZE)
792 count = PROC_BLOCK_SIZE;
793 if (!(page = __get_free_page(GFP_KERNEL)))
794 return -ENOMEM;
795
796 length = PROC_I(inode)->op.proc_read(task, (char*)page);
797
798 if (length >= 0)
799 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length);
800 free_page(page);
801 return length;
802 }
803
804 static struct file_operations proc_info_file_operations = {
805 .read = proc_info_read,
806 };
807
808 static int mem_open(struct inode* inode, struct file* file)
809 {
810 file->private_data = (void*)((long)current->self_exec_id);
811 return 0;
812 }
813
814 static ssize_t mem_read(struct file * file, char __user * buf,
815 size_t count, loff_t *ppos)
816 {
817 struct task_struct *task = proc_task(file->f_dentry->d_inode);
818 char *page;
819 unsigned long src = *ppos;
820 int ret = -ESRCH;
821 struct mm_struct *mm;
822
823 if (!MAY_PTRACE(task) || !ptrace_may_attach(task))
824 goto out;
825
826 ret = -ENOMEM;
827 page = (char *)__get_free_page(GFP_USER);
828 if (!page)
829 goto out;
830
831 ret = 0;
832
833 mm = get_task_mm(task);
834 if (!mm)
835 goto out_free;
836
837 ret = -EIO;
838
839 if (file->private_data != (void*)((long)current->self_exec_id))
840 goto out_put;
841
842 ret = 0;
843
844 while (count > 0) {
845 int this_len, retval;
846
847 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
848 retval = access_process_vm(task, src, page, this_len, 0);
849 if (!retval || !MAY_PTRACE(task) || !ptrace_may_attach(task)) {
850 if (!ret)
851 ret = -EIO;
852 break;
853 }
854
855 if (copy_to_user(buf, page, retval)) {
856 ret = -EFAULT;
857 break;
858 }
859
860 ret += retval;
861 src += retval;
862 buf += retval;
863 count -= retval;
864 }
865 *ppos = src;
866
867 out_put:
868 mmput(mm);
869 out_free:
870 free_page((unsigned long) page);
871 out:
872 return ret;
873 }
874
875 #define mem_write NULL
876
877 #ifndef mem_write
878 /* This is a security hazard */
879 static ssize_t mem_write(struct file * file, const char * buf,
880 size_t count, loff_t *ppos)
881 {
882 int copied = 0;
883 char *page;
884 struct task_struct *task = proc_task(file->f_dentry->d_inode);
885 unsigned long dst = *ppos;
886
887 if (!MAY_PTRACE(task) || !ptrace_may_attach(task))
888 return -ESRCH;
889
890 page = (char *)__get_free_page(GFP_USER);
891 if (!page)
892 return -ENOMEM;
893
894 while (count > 0) {
895 int this_len, retval;
896
897 this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
898 if (copy_from_user(page, buf, this_len)) {
899 copied = -EFAULT;
900 break;
901 }
902 retval = access_process_vm(task, dst, page, this_len, 1);
903 if (!retval) {
904 if (!copied)
905 copied = -EIO;
906 break;
907 }
908 copied += retval;
909 buf += retval;
910 dst += retval;
911 count -= retval;
912 }
913 *ppos = dst;
914 free_page((unsigned long) page);
915 return copied;
916 }
917 #endif
918
919 static loff_t mem_lseek(struct file * file, loff_t offset, int orig)
920 {
921 switch (orig) {
922 case 0:
923 file->f_pos = offset;
924 break;
925 case 1:
926 file->f_pos += offset;
927 break;
928 default:
929 return -EINVAL;
930 }
931 force_successful_syscall_return();
932 return file->f_pos;
933 }
934
935 static struct file_operations proc_mem_operations = {
936 .llseek = mem_lseek,
937 .read = mem_read,
938 .write = mem_write,
939 .open = mem_open,
940 };
941
942 static ssize_t oom_adjust_read(struct file *file, char __user *buf,
943 size_t count, loff_t *ppos)
944 {
945 struct task_struct *task = proc_task(file->f_dentry->d_inode);
946 char buffer[8];
947 size_t len;
948 int oom_adjust = task->oomkilladj;
949 loff_t __ppos = *ppos;
950
951 len = sprintf(buffer, "%i\n", oom_adjust);
952 if (__ppos >= len)
953 return 0;
954 if (count > len-__ppos)
955 count = len-__ppos;
956 if (copy_to_user(buf, buffer + __ppos, count))
957 return -EFAULT;
958 *ppos = __ppos + count;
959 return count;
960 }
961
962 static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
963 size_t count, loff_t *ppos)
964 {
965 struct task_struct *task = proc_task(file->f_dentry->d_inode);
966 char buffer[8], *end;
967 int oom_adjust;
968
969 if (!capable(CAP_SYS_RESOURCE))
970 return -EPERM;
971 memset(buffer, 0, 8);
972 if (count > 6)
973 count = 6;
974 if (copy_from_user(buffer, buf, count))
975 return -EFAULT;
976 oom_adjust = simple_strtol(buffer, &end, 0);
977 if ((oom_adjust < -16 || oom_adjust > 15) && oom_adjust != OOM_DISABLE)
978 return -EINVAL;
979 if (*end == '\n')
980 end++;
981 task->oomkilladj = oom_adjust;
982 if (end - buffer == 0)
983 return -EIO;
984 return end - buffer;
985 }
986
987 static struct file_operations proc_oom_adjust_operations = {
988 .read = oom_adjust_read,
989 .write = oom_adjust_write,
990 };
991
992 static struct inode_operations proc_mem_inode_operations = {
993 .permission = proc_permission,
994 };
995
996 #ifdef CONFIG_AUDITSYSCALL
997 #define TMPBUFLEN 21
998 static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
999 size_t count, loff_t *ppos)
1000 {
1001 struct inode * inode = file->f_dentry->d_inode;
1002 struct task_struct *task = proc_task(inode);
1003 ssize_t length;
1004 char tmpbuf[TMPBUFLEN];
1005
1006 length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1007 audit_get_loginuid(task->audit_context));
1008 return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1009 }
1010
1011 static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
1012 size_t count, loff_t *ppos)
1013 {
1014 struct inode * inode = file->f_dentry->d_inode;
1015 char *page, *tmp;
1016 ssize_t length;
1017 struct task_struct *task = proc_task(inode);
1018 uid_t loginuid;
1019
1020 if (!capable(CAP_AUDIT_CONTROL))
1021 return -EPERM;
1022
1023 if (current != task)
1024 return -EPERM;
1025
1026 if (count >= PAGE_SIZE)
1027 count = PAGE_SIZE - 1;
1028
1029 if (*ppos != 0) {
1030 /* No partial writes. */
1031 return -EINVAL;
1032 }
1033 page = (char*)__get_free_page(GFP_USER);
1034 if (!page)
1035 return -ENOMEM;
1036 length = -EFAULT;
1037 if (copy_from_user(page, buf, count))
1038 goto out_free_page;
1039
1040 page[count] = '\0';
1041 loginuid = simple_strtoul(page, &tmp, 10);
1042 if (tmp == page) {
1043 length = -EINVAL;
1044 goto out_free_page;
1045
1046 }
1047 length = audit_set_loginuid(task, loginuid);
1048 if (likely(length == 0))
1049 length = count;
1050
1051 out_free_page:
1052 free_page((unsigned long) page);
1053 return length;
1054 }
1055
1056 static struct file_operations proc_loginuid_operations = {
1057 .read = proc_loginuid_read,
1058 .write = proc_loginuid_write,
1059 };
1060 #endif
1061
1062 #ifdef CONFIG_SECCOMP
1063 static ssize_t seccomp_read(struct file *file, char __user *buf,
1064 size_t count, loff_t *ppos)
1065 {
1066 struct task_struct *tsk = proc_task(file->f_dentry->d_inode);
1067 char __buf[20];
1068 loff_t __ppos = *ppos;
1069 size_t len;
1070
1071 /* no need to print the trailing zero, so use only len */
1072 len = sprintf(__buf, "%u\n", tsk->seccomp.mode);
1073 if (__ppos >= len)
1074 return 0;
1075 if (count > len - __ppos)
1076 count = len - __ppos;
1077 if (copy_to_user(buf, __buf + __ppos, count))
1078 return -EFAULT;
1079 *ppos = __ppos + count;
1080 return count;
1081 }
1082
1083 static ssize_t seccomp_write(struct file *file, const char __user *buf,
1084 size_t count, loff_t *ppos)
1085 {
1086 struct task_struct *tsk = proc_task(file->f_dentry->d_inode);
1087 char __buf[20], *end;
1088 unsigned int seccomp_mode;
1089
1090 /* can set it only once to be even more secure */
1091 if (unlikely(tsk->seccomp.mode))
1092 return -EPERM;
1093
1094 memset(__buf, 0, sizeof(__buf));
1095 count = min(count, sizeof(__buf) - 1);
1096 if (copy_from_user(__buf, buf, count))
1097 return -EFAULT;
1098 seccomp_mode = simple_strtoul(__buf, &end, 0);
1099 if (*end == '\n')
1100 end++;
1101 if (seccomp_mode && seccomp_mode <= NR_SECCOMP_MODES) {
1102 tsk->seccomp.mode = seccomp_mode;
1103 set_tsk_thread_flag(tsk, TIF_SECCOMP);
1104 } else
1105 return -EINVAL;
1106 if (unlikely(!(end - __buf)))
1107 return -EIO;
1108 return end - __buf;
1109 }
1110
1111 static struct file_operations proc_seccomp_operations = {
1112 .read = seccomp_read,
1113 .write = seccomp_write,
1114 };
1115 #endif /* CONFIG_SECCOMP */
1116
1117 static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd)
1118 {
1119 struct inode *inode = dentry->d_inode;
1120 int error = -EACCES;
1121
1122 /* We don't need a base pointer in the /proc filesystem */
1123 path_release(nd);
1124
1125 if (current->fsuid != inode->i_uid && !capable(CAP_DAC_OVERRIDE))
1126 goto out;
1127 error = proc_check_root(inode);
1128 if (error)
1129 goto out;
1130
1131 error = PROC_I(inode)->op.proc_get_link(inode, &nd->dentry, &nd->mnt);
1132 nd->last_type = LAST_BIND;
1133 out:
1134 return ERR_PTR(error);
1135 }
1136
1137 static int do_proc_readlink(struct dentry *dentry, struct vfsmount *mnt,
1138 char __user *buffer, int buflen)
1139 {
1140 struct inode * inode;
1141 char *tmp = (char*)__get_free_page(GFP_KERNEL), *path;
1142 int len;
1143
1144 if (!tmp)
1145 return -ENOMEM;
1146
1147 inode = dentry->d_inode;
1148 path = d_path(dentry, mnt, tmp, PAGE_SIZE);
1149 len = PTR_ERR(path);
1150 if (IS_ERR(path))
1151 goto out;
1152 len = tmp + PAGE_SIZE - 1 - path;
1153
1154 if (len > buflen)
1155 len = buflen;
1156 if (copy_to_user(buffer, path, len))
1157 len = -EFAULT;
1158 out:
1159 free_page((unsigned long)tmp);
1160 return len;
1161 }
1162
1163 static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
1164 {
1165 int error = -EACCES;
1166 struct inode *inode = dentry->d_inode;
1167 struct dentry *de;
1168 struct vfsmount *mnt = NULL;
1169
1170
1171 if (current->fsuid != inode->i_uid && !capable(CAP_DAC_OVERRIDE))
1172 goto out;
1173 error = proc_check_root(inode);
1174 if (error)
1175 goto out;
1176
1177 error = PROC_I(inode)->op.proc_get_link(inode, &de, &mnt);
1178 if (error)
1179 goto out;
1180
1181 error = do_proc_readlink(de, mnt, buffer, buflen);
1182 dput(de);
1183 mntput(mnt);
1184 out:
1185 return error;
1186 }
1187
1188 static struct inode_operations proc_pid_link_inode_operations = {
1189 .readlink = proc_pid_readlink,
1190 .follow_link = proc_pid_follow_link
1191 };
1192
1193 #define NUMBUF 10
1194
1195 static int proc_readfd(struct file * filp, void * dirent, filldir_t filldir)
1196 {
1197 struct dentry *dentry = filp->f_dentry;
1198 struct inode *inode = dentry->d_inode;
1199 struct task_struct *p = proc_task(inode);
1200 unsigned int fd, tid, ino;
1201 int retval;
1202 char buf[NUMBUF];
1203 struct files_struct * files;
1204 struct fdtable *fdt;
1205
1206 retval = -ENOENT;
1207 if (!pid_alive(p))
1208 goto out;
1209 retval = 0;
1210 tid = p->pid;
1211
1212 fd = filp->f_pos;
1213 switch (fd) {
1214 case 0:
1215 if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
1216 goto out;
1217 filp->f_pos++;
1218 case 1:
1219 ino = parent_ino(dentry);
1220 if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
1221 goto out;
1222 filp->f_pos++;
1223 default:
1224 files = get_files_struct(p);
1225 if (!files)
1226 goto out;
1227 rcu_read_lock();
1228 fdt = files_fdtable(files);
1229 for (fd = filp->f_pos-2;
1230 fd < fdt->max_fds;
1231 fd++, filp->f_pos++) {
1232 unsigned int i,j;
1233
1234 if (!fcheck_files(files, fd))
1235 continue;
1236 rcu_read_unlock();
1237
1238 j = NUMBUF;
1239 i = fd;
1240 do {
1241 j--;
1242 buf[j] = '0' + (i % 10);
1243 i /= 10;
1244 } while (i);
1245
1246 ino = fake_ino(tid, PROC_TID_FD_DIR + fd);
1247 if (filldir(dirent, buf+j, NUMBUF-j, fd+2, ino, DT_LNK) < 0) {
1248 rcu_read_lock();
1249 break;
1250 }
1251 rcu_read_lock();
1252 }
1253 rcu_read_unlock();
1254 put_files_struct(files);
1255 }
1256 out:
1257 return retval;
1258 }
1259
1260 static int proc_pident_readdir(struct file *filp,
1261 void *dirent, filldir_t filldir,
1262 struct pid_entry *ents, unsigned int nents)
1263 {
1264 int i;
1265 int pid;
1266 struct dentry *dentry = filp->f_dentry;
1267 struct inode *inode = dentry->d_inode;
1268 struct pid_entry *p;
1269 ino_t ino;
1270 int ret;
1271
1272 ret = -ENOENT;
1273 if (!pid_alive(proc_task(inode)))
1274 goto out;
1275
1276 ret = 0;
1277 pid = proc_task(inode)->pid;
1278 i = filp->f_pos;
1279 switch (i) {
1280 case 0:
1281 ino = inode->i_ino;
1282 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
1283 goto out;
1284 i++;
1285 filp->f_pos++;
1286 /* fall through */
1287 case 1:
1288 ino = parent_ino(dentry);
1289 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
1290 goto out;
1291 i++;
1292 filp->f_pos++;
1293 /* fall through */
1294 default:
1295 i -= 2;
1296 if (i >= nents) {
1297 ret = 1;
1298 goto out;
1299 }
1300 p = ents + i;
1301 while (p->name) {
1302 if (filldir(dirent, p->name, p->len, filp->f_pos,
1303 fake_ino(pid, p->type), p->mode >> 12) < 0)
1304 goto out;
1305 filp->f_pos++;
1306 p++;
1307 }
1308 }
1309
1310 ret = 1;
1311 out:
1312 return ret;
1313 }
1314
1315 static int proc_tgid_base_readdir(struct file * filp,
1316 void * dirent, filldir_t filldir)
1317 {
1318 return proc_pident_readdir(filp,dirent,filldir,
1319 tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff));
1320 }
1321
1322 static int proc_tid_base_readdir(struct file * filp,
1323 void * dirent, filldir_t filldir)
1324 {
1325 return proc_pident_readdir(filp,dirent,filldir,
1326 tid_base_stuff,ARRAY_SIZE(tid_base_stuff));
1327 }
1328
1329 /* building an inode */
1330
1331 static int task_dumpable(struct task_struct *task)
1332 {
1333 int dumpable = 0;
1334 struct mm_struct *mm;
1335
1336 task_lock(task);
1337 mm = task->mm;
1338 if (mm)
1339 dumpable = mm->dumpable;
1340 task_unlock(task);
1341 if(dumpable == 1)
1342 return 1;
1343 return 0;
1344 }
1345
1346
1347 static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task, int ino)
1348 {
1349 struct inode * inode;
1350 struct proc_inode *ei;
1351
1352 /* We need a new inode */
1353
1354 inode = new_inode(sb);
1355 if (!inode)
1356 goto out;
1357
1358 /* Common stuff */
1359 ei = PROC_I(inode);
1360 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
1361 inode->i_ino = fake_ino(task->pid, ino);
1362
1363 if (!pid_alive(task))
1364 goto out_unlock;
1365
1366 /*
1367 * grab the reference to task.
1368 */
1369 get_task_struct(task);
1370 ei->task = task;
1371 ei->type = ino;
1372 inode->i_uid = 0;
1373 inode->i_gid = 0;
1374 if (task_dumpable(task)) {
1375 inode->i_uid = task->euid;
1376 inode->i_gid = task->egid;
1377 }
1378 security_task_to_inode(task, inode);
1379
1380 out:
1381 return inode;
1382
1383 out_unlock:
1384 iput(inode);
1385 return NULL;
1386 }
1387
1388 /* dentry stuff */
1389
1390 /*
1391 * Exceptional case: normally we are not allowed to unhash a busy
1392 * directory. In this case, however, we can do it - no aliasing problems
1393 * due to the way we treat inodes.
1394 *
1395 * Rewrite the inode's ownerships here because the owning task may have
1396 * performed a setuid(), etc.
1397 */
1398 static int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
1399 {
1400 struct inode *inode = dentry->d_inode;
1401 struct task_struct *task = proc_task(inode);
1402 if (pid_alive(task)) {
1403 if (task_dumpable(task)) {
1404 inode->i_uid = task->euid;
1405 inode->i_gid = task->egid;
1406 } else {
1407 inode->i_uid = 0;
1408 inode->i_gid = 0;
1409 }
1410 security_task_to_inode(task, inode);
1411 return 1;
1412 }
1413 d_drop(dentry);
1414 return 0;
1415 }
1416
1417 static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
1418 {
1419 struct inode *inode = dentry->d_inode;
1420 struct task_struct *task = proc_task(inode);
1421 int fd = proc_type(inode) - PROC_TID_FD_DIR;
1422 struct files_struct *files;
1423
1424 files = get_files_struct(task);
1425 if (files) {
1426 rcu_read_lock();
1427 if (fcheck_files(files, fd)) {
1428 rcu_read_unlock();
1429 put_files_struct(files);
1430 if (task_dumpable(task)) {
1431 inode->i_uid = task->euid;
1432 inode->i_gid = task->egid;
1433 } else {
1434 inode->i_uid = 0;
1435 inode->i_gid = 0;
1436 }
1437 security_task_to_inode(task, inode);
1438 return 1;
1439 }
1440 rcu_read_unlock();
1441 put_files_struct(files);
1442 }
1443 d_drop(dentry);
1444 return 0;
1445 }
1446
1447 static void pid_base_iput(struct dentry *dentry, struct inode *inode)
1448 {
1449 struct task_struct *task = proc_task(inode);
1450 spin_lock(&task->proc_lock);
1451 if (task->proc_dentry == dentry)
1452 task->proc_dentry = NULL;
1453 spin_unlock(&task->proc_lock);
1454 iput(inode);
1455 }
1456
1457 static int pid_delete_dentry(struct dentry * dentry)
1458 {
1459 /* Is the task we represent dead?
1460 * If so, then don't put the dentry on the lru list,
1461 * kill it immediately.
1462 */
1463 return !pid_alive(proc_task(dentry->d_inode));
1464 }
1465
1466 static struct dentry_operations tid_fd_dentry_operations =
1467 {
1468 .d_revalidate = tid_fd_revalidate,
1469 .d_delete = pid_delete_dentry,
1470 };
1471
1472 static struct dentry_operations pid_dentry_operations =
1473 {
1474 .d_revalidate = pid_revalidate,
1475 .d_delete = pid_delete_dentry,
1476 };
1477
1478 static struct dentry_operations pid_base_dentry_operations =
1479 {
1480 .d_revalidate = pid_revalidate,
1481 .d_iput = pid_base_iput,
1482 .d_delete = pid_delete_dentry,
1483 };
1484
1485 /* Lookups */
1486
1487 static unsigned name_to_int(struct dentry *dentry)
1488 {
1489 const char *name = dentry->d_name.name;
1490 int len = dentry->d_name.len;
1491 unsigned n = 0;
1492
1493 if (len > 1 && *name == '0')
1494 goto out;
1495 while (len-- > 0) {
1496 unsigned c = *name++ - '0';
1497 if (c > 9)
1498 goto out;
1499 if (n >= (~0U-9)/10)
1500 goto out;
1501 n *= 10;
1502 n += c;
1503 }
1504 return n;
1505 out:
1506 return ~0U;
1507 }
1508
1509 /* SMP-safe */
1510 static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry, struct nameidata *nd)
1511 {
1512 struct task_struct *task = proc_task(dir);
1513 unsigned fd = name_to_int(dentry);
1514 struct file * file;
1515 struct files_struct * files;
1516 struct inode *inode;
1517 struct proc_inode *ei;
1518
1519 if (fd == ~0U)
1520 goto out;
1521 if (!pid_alive(task))
1522 goto out;
1523
1524 inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_FD_DIR+fd);
1525 if (!inode)
1526 goto out;
1527 ei = PROC_I(inode);
1528 files = get_files_struct(task);
1529 if (!files)
1530 goto out_unlock;
1531 inode->i_mode = S_IFLNK;
1532
1533 /*
1534 * We are not taking a ref to the file structure, so we must
1535 * hold ->file_lock.
1536 */
1537 spin_lock(&files->file_lock);
1538 file = fcheck_files(files, fd);
1539 if (!file)
1540 goto out_unlock2;
1541 if (file->f_mode & 1)
1542 inode->i_mode |= S_IRUSR | S_IXUSR;
1543 if (file->f_mode & 2)
1544 inode->i_mode |= S_IWUSR | S_IXUSR;
1545 spin_unlock(&files->file_lock);
1546 put_files_struct(files);
1547 inode->i_op = &proc_pid_link_inode_operations;
1548 inode->i_size = 64;
1549 ei->op.proc_get_link = proc_fd_link;
1550 dentry->d_op = &tid_fd_dentry_operations;
1551 d_add(dentry, inode);
1552 return NULL;
1553
1554 out_unlock2:
1555 spin_unlock(&files->file_lock);
1556 put_files_struct(files);
1557 out_unlock:
1558 iput(inode);
1559 out:
1560 return ERR_PTR(-ENOENT);
1561 }
1562
1563 static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir);
1564 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd);
1565
1566 static struct file_operations proc_fd_operations = {
1567 .read = generic_read_dir,
1568 .readdir = proc_readfd,
1569 };
1570
1571 static struct file_operations proc_task_operations = {
1572 .read = generic_read_dir,
1573 .readdir = proc_task_readdir,
1574 };
1575
1576 /*
1577 * proc directories can do almost nothing..
1578 */
1579 static struct inode_operations proc_fd_inode_operations = {
1580 .lookup = proc_lookupfd,
1581 .permission = proc_permission,
1582 };
1583
1584 static struct inode_operations proc_task_inode_operations = {
1585 .lookup = proc_task_lookup,
1586 .permission = proc_task_permission,
1587 };
1588
1589 #ifdef CONFIG_SECURITY
1590 static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
1591 size_t count, loff_t *ppos)
1592 {
1593 struct inode * inode = file->f_dentry->d_inode;
1594 unsigned long page;
1595 ssize_t length;
1596 struct task_struct *task = proc_task(inode);
1597
1598 if (count > PAGE_SIZE)
1599 count = PAGE_SIZE;
1600 if (!(page = __get_free_page(GFP_KERNEL)))
1601 return -ENOMEM;
1602
1603 length = security_getprocattr(task,
1604 (char*)file->f_dentry->d_name.name,
1605 (void*)page, count);
1606 if (length >= 0)
1607 length = simple_read_from_buffer(buf, count, ppos, (char *)page, length);
1608 free_page(page);
1609 return length;
1610 }
1611
1612 static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
1613 size_t count, loff_t *ppos)
1614 {
1615 struct inode * inode = file->f_dentry->d_inode;
1616 char *page;
1617 ssize_t length;
1618 struct task_struct *task = proc_task(inode);
1619
1620 if (count > PAGE_SIZE)
1621 count = PAGE_SIZE;
1622 if (*ppos != 0) {
1623 /* No partial writes. */
1624 return -EINVAL;
1625 }
1626 page = (char*)__get_free_page(GFP_USER);
1627 if (!page)
1628 return -ENOMEM;
1629 length = -EFAULT;
1630 if (copy_from_user(page, buf, count))
1631 goto out;
1632
1633 length = security_setprocattr(task,
1634 (char*)file->f_dentry->d_name.name,
1635 (void*)page, count);
1636 out:
1637 free_page((unsigned long) page);
1638 return length;
1639 }
1640
1641 static struct file_operations proc_pid_attr_operations = {
1642 .read = proc_pid_attr_read,
1643 .write = proc_pid_attr_write,
1644 };
1645
1646 static struct file_operations proc_tid_attr_operations;
1647 static struct inode_operations proc_tid_attr_inode_operations;
1648 static struct file_operations proc_tgid_attr_operations;
1649 static struct inode_operations proc_tgid_attr_inode_operations;
1650 #endif
1651
1652 static int get_tid_list(int index, unsigned int *tids, struct inode *dir);
1653
1654 /* SMP-safe */
1655 static struct dentry *proc_pident_lookup(struct inode *dir,
1656 struct dentry *dentry,
1657 struct pid_entry *ents)
1658 {
1659 struct inode *inode;
1660 int error;
1661 struct task_struct *task = proc_task(dir);
1662 struct pid_entry *p;
1663 struct proc_inode *ei;
1664
1665 error = -ENOENT;
1666 inode = NULL;
1667
1668 if (!pid_alive(task))
1669 goto out;
1670
1671 for (p = ents; p->name; p++) {
1672 if (p->len != dentry->d_name.len)
1673 continue;
1674 if (!memcmp(dentry->d_name.name, p->name, p->len))
1675 break;
1676 }
1677 if (!p->name)
1678 goto out;
1679
1680 error = -EINVAL;
1681 inode = proc_pid_make_inode(dir->i_sb, task, p->type);
1682 if (!inode)
1683 goto out;
1684
1685 ei = PROC_I(inode);
1686 inode->i_mode = p->mode;
1687 /*
1688 * Yes, it does not scale. And it should not. Don't add
1689 * new entries into /proc/<tgid>/ without very good reasons.
1690 */
1691 switch(p->type) {
1692 case PROC_TGID_TASK:
1693 inode->i_nlink = 2 + get_tid_list(2, NULL, dir);
1694 inode->i_op = &proc_task_inode_operations;
1695 inode->i_fop = &proc_task_operations;
1696 break;
1697 case PROC_TID_FD:
1698 case PROC_TGID_FD:
1699 inode->i_nlink = 2;
1700 inode->i_op = &proc_fd_inode_operations;
1701 inode->i_fop = &proc_fd_operations;
1702 break;
1703 case PROC_TID_EXE:
1704 case PROC_TGID_EXE:
1705 inode->i_op = &proc_pid_link_inode_operations;
1706 ei->op.proc_get_link = proc_exe_link;
1707 break;
1708 case PROC_TID_CWD:
1709 case PROC_TGID_CWD:
1710 inode->i_op = &proc_pid_link_inode_operations;
1711 ei->op.proc_get_link = proc_cwd_link;
1712 break;
1713 case PROC_TID_ROOT:
1714 case PROC_TGID_ROOT:
1715 inode->i_op = &proc_pid_link_inode_operations;
1716 ei->op.proc_get_link = proc_root_link;
1717 break;
1718 case PROC_TID_ENVIRON:
1719 case PROC_TGID_ENVIRON:
1720 inode->i_fop = &proc_info_file_operations;
1721 ei->op.proc_read = proc_pid_environ;
1722 break;
1723 case PROC_TID_AUXV:
1724 case PROC_TGID_AUXV:
1725 inode->i_fop = &proc_info_file_operations;
1726 ei->op.proc_read = proc_pid_auxv;
1727 break;
1728 case PROC_TID_STATUS:
1729 case PROC_TGID_STATUS:
1730 inode->i_fop = &proc_info_file_operations;
1731 ei->op.proc_read = proc_pid_status;
1732 break;
1733 case PROC_TID_STAT:
1734 inode->i_fop = &proc_info_file_operations;
1735 ei->op.proc_read = proc_tid_stat;
1736 break;
1737 case PROC_TGID_STAT:
1738 inode->i_fop = &proc_info_file_operations;
1739 ei->op.proc_read = proc_tgid_stat;
1740 break;
1741 case PROC_TID_CMDLINE:
1742 case PROC_TGID_CMDLINE:
1743 inode->i_fop = &proc_info_file_operations;
1744 ei->op.proc_read = proc_pid_cmdline;
1745 break;
1746 case PROC_TID_STATM:
1747 case PROC_TGID_STATM:
1748 inode->i_fop = &proc_info_file_operations;
1749 ei->op.proc_read = proc_pid_statm;
1750 break;
1751 case PROC_TID_MAPS:
1752 case PROC_TGID_MAPS:
1753 inode->i_fop = &proc_maps_operations;
1754 break;
1755 #ifdef CONFIG_NUMA
1756 case PROC_TID_NUMA_MAPS:
1757 case PROC_TGID_NUMA_MAPS:
1758 inode->i_fop = &proc_numa_maps_operations;
1759 break;
1760 #endif
1761 case PROC_TID_MEM:
1762 case PROC_TGID_MEM:
1763 inode->i_op = &proc_mem_inode_operations;
1764 inode->i_fop = &proc_mem_operations;
1765 break;
1766 #ifdef CONFIG_SECCOMP
1767 case PROC_TID_SECCOMP:
1768 case PROC_TGID_SECCOMP:
1769 inode->i_fop = &proc_seccomp_operations;
1770 break;
1771 #endif /* CONFIG_SECCOMP */
1772 case PROC_TID_MOUNTS:
1773 case PROC_TGID_MOUNTS:
1774 inode->i_fop = &proc_mounts_operations;
1775 break;
1776 #ifdef CONFIG_MMU
1777 case PROC_TID_SMAPS:
1778 case PROC_TGID_SMAPS:
1779 inode->i_fop = &proc_smaps_operations;
1780 break;
1781 #endif
1782 case PROC_TID_MOUNTSTATS:
1783 case PROC_TGID_MOUNTSTATS:
1784 inode->i_fop = &proc_mountstats_operations;
1785 break;
1786 #ifdef CONFIG_SECURITY
1787 case PROC_TID_ATTR:
1788 inode->i_nlink = 2;
1789 inode->i_op = &proc_tid_attr_inode_operations;
1790 inode->i_fop = &proc_tid_attr_operations;
1791 break;
1792 case PROC_TGID_ATTR:
1793 inode->i_nlink = 2;
1794 inode->i_op = &proc_tgid_attr_inode_operations;
1795 inode->i_fop = &proc_tgid_attr_operations;
1796 break;
1797 case PROC_TID_ATTR_CURRENT:
1798 case PROC_TGID_ATTR_CURRENT:
1799 case PROC_TID_ATTR_PREV:
1800 case PROC_TGID_ATTR_PREV:
1801 case PROC_TID_ATTR_EXEC:
1802 case PROC_TGID_ATTR_EXEC:
1803 case PROC_TID_ATTR_FSCREATE:
1804 case PROC_TGID_ATTR_FSCREATE:
1805 case PROC_TID_ATTR_KEYCREATE:
1806 case PROC_TGID_ATTR_KEYCREATE:
1807 inode->i_fop = &proc_pid_attr_operations;
1808 break;
1809 #endif
1810 #ifdef CONFIG_KALLSYMS
1811 case PROC_TID_WCHAN:
1812 case PROC_TGID_WCHAN:
1813 inode->i_fop = &proc_info_file_operations;
1814 ei->op.proc_read = proc_pid_wchan;
1815 break;
1816 #endif
1817 #ifdef CONFIG_SCHEDSTATS
1818 case PROC_TID_SCHEDSTAT:
1819 case PROC_TGID_SCHEDSTAT:
1820 inode->i_fop = &proc_info_file_operations;
1821 ei->op.proc_read = proc_pid_schedstat;
1822 break;
1823 #endif
1824 #ifdef CONFIG_CPUSETS
1825 case PROC_TID_CPUSET:
1826 case PROC_TGID_CPUSET:
1827 inode->i_fop = &proc_cpuset_operations;
1828 break;
1829 #endif
1830 case PROC_TID_OOM_SCORE:
1831 case PROC_TGID_OOM_SCORE:
1832 inode->i_fop = &proc_info_file_operations;
1833 ei->op.proc_read = proc_oom_score;
1834 break;
1835 case PROC_TID_OOM_ADJUST:
1836 case PROC_TGID_OOM_ADJUST:
1837 inode->i_fop = &proc_oom_adjust_operations;
1838 break;
1839 #ifdef CONFIG_AUDITSYSCALL
1840 case PROC_TID_LOGINUID:
1841 case PROC_TGID_LOGINUID:
1842 inode->i_fop = &proc_loginuid_operations;
1843 break;
1844 #endif
1845 default:
1846 printk("procfs: impossible type (%d)",p->type);
1847 iput(inode);
1848 return ERR_PTR(-EINVAL);
1849 }
1850 dentry->d_op = &pid_dentry_operations;
1851 d_add(dentry, inode);
1852 return NULL;
1853
1854 out:
1855 return ERR_PTR(error);
1856 }
1857
1858 static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
1859 return proc_pident_lookup(dir, dentry, tgid_base_stuff);
1860 }
1861
1862 static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
1863 return proc_pident_lookup(dir, dentry, tid_base_stuff);
1864 }
1865
1866 static struct file_operations proc_tgid_base_operations = {
1867 .read = generic_read_dir,
1868 .readdir = proc_tgid_base_readdir,
1869 };
1870
1871 static struct file_operations proc_tid_base_operations = {
1872 .read = generic_read_dir,
1873 .readdir = proc_tid_base_readdir,
1874 };
1875
1876 static struct inode_operations proc_tgid_base_inode_operations = {
1877 .lookup = proc_tgid_base_lookup,
1878 };
1879
1880 static struct inode_operations proc_tid_base_inode_operations = {
1881 .lookup = proc_tid_base_lookup,
1882 };
1883
1884 #ifdef CONFIG_SECURITY
1885 static int proc_tgid_attr_readdir(struct file * filp,
1886 void * dirent, filldir_t filldir)
1887 {
1888 return proc_pident_readdir(filp,dirent,filldir,
1889 tgid_attr_stuff,ARRAY_SIZE(tgid_attr_stuff));
1890 }
1891
1892 static int proc_tid_attr_readdir(struct file * filp,
1893 void * dirent, filldir_t filldir)
1894 {
1895 return proc_pident_readdir(filp,dirent,filldir,
1896 tid_attr_stuff,ARRAY_SIZE(tid_attr_stuff));
1897 }
1898
1899 static struct file_operations proc_tgid_attr_operations = {
1900 .read = generic_read_dir,
1901 .readdir = proc_tgid_attr_readdir,
1902 };
1903
1904 static struct file_operations proc_tid_attr_operations = {
1905 .read = generic_read_dir,
1906 .readdir = proc_tid_attr_readdir,
1907 };
1908
1909 static struct dentry *proc_tgid_attr_lookup(struct inode *dir,
1910 struct dentry *dentry, struct nameidata *nd)
1911 {
1912 return proc_pident_lookup(dir, dentry, tgid_attr_stuff);
1913 }
1914
1915 static struct dentry *proc_tid_attr_lookup(struct inode *dir,
1916 struct dentry *dentry, struct nameidata *nd)
1917 {
1918 return proc_pident_lookup(dir, dentry, tid_attr_stuff);
1919 }
1920
1921 static struct inode_operations proc_tgid_attr_inode_operations = {
1922 .lookup = proc_tgid_attr_lookup,
1923 };
1924
1925 static struct inode_operations proc_tid_attr_inode_operations = {
1926 .lookup = proc_tid_attr_lookup,
1927 };
1928 #endif
1929
1930 /*
1931 * /proc/self:
1932 */
1933 static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
1934 int buflen)
1935 {
1936 char tmp[30];
1937 sprintf(tmp, "%d", current->tgid);
1938 return vfs_readlink(dentry,buffer,buflen,tmp);
1939 }
1940
1941 static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
1942 {
1943 char tmp[30];
1944 sprintf(tmp, "%d", current->tgid);
1945 return ERR_PTR(vfs_follow_link(nd,tmp));
1946 }
1947
1948 static struct inode_operations proc_self_inode_operations = {
1949 .readlink = proc_self_readlink,
1950 .follow_link = proc_self_follow_link,
1951 };
1952
1953 /**
1954 * proc_pid_unhash - Unhash /proc/@pid entry from the dcache.
1955 * @p: task that should be flushed.
1956 *
1957 * Drops the /proc/@pid dcache entry from the hash chains.
1958 *
1959 * Dropping /proc/@pid entries and detach_pid must be synchroneous,
1960 * otherwise e.g. /proc/@pid/exe might point to the wrong executable,
1961 * if the pid value is immediately reused. This is enforced by
1962 * - caller must acquire spin_lock(p->proc_lock)
1963 * - must be called before detach_pid()
1964 * - proc_pid_lookup acquires proc_lock, and checks that
1965 * the target is not dead by looking at the attach count
1966 * of PIDTYPE_PID.
1967 */
1968
1969 struct dentry *proc_pid_unhash(struct task_struct *p)
1970 {
1971 struct dentry *proc_dentry;
1972
1973 proc_dentry = p->proc_dentry;
1974 if (proc_dentry != NULL) {
1975
1976 spin_lock(&dcache_lock);
1977 spin_lock(&proc_dentry->d_lock);
1978 if (!d_unhashed(proc_dentry)) {
1979 dget_locked(proc_dentry);
1980 __d_drop(proc_dentry);
1981 spin_unlock(&proc_dentry->d_lock);
1982 } else {
1983 spin_unlock(&proc_dentry->d_lock);
1984 proc_dentry = NULL;
1985 }
1986 spin_unlock(&dcache_lock);
1987 }
1988 return proc_dentry;
1989 }
1990
1991 /**
1992 * proc_pid_flush - recover memory used by stale /proc/@pid/x entries
1993 * @proc_dentry: directoy to prune.
1994 *
1995 * Shrink the /proc directory that was used by the just killed thread.
1996 */
1997
1998 void proc_pid_flush(struct dentry *proc_dentry)
1999 {
2000 might_sleep();
2001 if(proc_dentry != NULL) {
2002 shrink_dcache_parent(proc_dentry);
2003 dput(proc_dentry);
2004 }
2005 }
2006
2007 /* SMP-safe */
2008 struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
2009 {
2010 struct task_struct *task;
2011 struct inode *inode;
2012 struct proc_inode *ei;
2013 unsigned tgid;
2014 int died;
2015
2016 if (dentry->d_name.len == 4 && !memcmp(dentry->d_name.name,"self",4)) {
2017 inode = new_inode(dir->i_sb);
2018 if (!inode)
2019 return ERR_PTR(-ENOMEM);
2020 ei = PROC_I(inode);
2021 inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
2022 inode->i_ino = fake_ino(0, PROC_TGID_INO);
2023 ei->pde = NULL;
2024 inode->i_mode = S_IFLNK|S_IRWXUGO;
2025 inode->i_uid = inode->i_gid = 0;
2026 inode->i_size = 64;
2027 inode->i_op = &proc_self_inode_operations;
2028 d_add(dentry, inode);
2029 return NULL;
2030 }
2031 tgid = name_to_int(dentry);
2032 if (tgid == ~0U)
2033 goto out;
2034
2035 read_lock(&tasklist_lock);
2036 task = find_task_by_pid(tgid);
2037 if (task)
2038 get_task_struct(task);
2039 read_unlock(&tasklist_lock);
2040 if (!task)
2041 goto out;
2042
2043 inode = proc_pid_make_inode(dir->i_sb, task, PROC_TGID_INO);
2044
2045
2046 if (!inode) {
2047 put_task_struct(task);
2048 goto out;
2049 }
2050 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
2051 inode->i_op = &proc_tgid_base_inode_operations;
2052 inode->i_fop = &proc_tgid_base_operations;
2053 inode->i_flags|=S_IMMUTABLE;
2054 #ifdef CONFIG_SECURITY
2055 inode->i_nlink = 5;
2056 #else
2057 inode->i_nlink = 4;
2058 #endif
2059
2060 dentry->d_op = &pid_base_dentry_operations;
2061
2062 died = 0;
2063 d_add(dentry, inode);
2064 spin_lock(&task->proc_lock);
2065 task->proc_dentry = dentry;
2066 if (!pid_alive(task)) {
2067 dentry = proc_pid_unhash(task);
2068 died = 1;
2069 }
2070 spin_unlock(&task->proc_lock);
2071
2072 put_task_struct(task);
2073 if (died) {
2074 proc_pid_flush(dentry);
2075 goto out;
2076 }
2077 return NULL;
2078 out:
2079 return ERR_PTR(-ENOENT);
2080 }
2081
2082 /* SMP-safe */
2083 static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
2084 {
2085 struct task_struct *task;
2086 struct task_struct *leader = proc_task(dir);
2087 struct inode *inode;
2088 unsigned tid;
2089
2090 tid = name_to_int(dentry);
2091 if (tid == ~0U)
2092 goto out;
2093
2094 read_lock(&tasklist_lock);
2095 task = find_task_by_pid(tid);
2096 if (task)
2097 get_task_struct(task);
2098 read_unlock(&tasklist_lock);
2099 if (!task)
2100 goto out;
2101 if (leader->tgid != task->tgid)
2102 goto out_drop_task;
2103
2104 inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_INO);
2105
2106
2107 if (!inode)
2108 goto out_drop_task;
2109 inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
2110 inode->i_op = &proc_tid_base_inode_operations;
2111 inode->i_fop = &proc_tid_base_operations;
2112 inode->i_flags|=S_IMMUTABLE;
2113 #ifdef CONFIG_SECURITY
2114 inode->i_nlink = 4;
2115 #else
2116 inode->i_nlink = 3;
2117 #endif
2118
2119 dentry->d_op = &pid_base_dentry_operations;
2120
2121 d_add(dentry, inode);
2122
2123 put_task_struct(task);
2124 return NULL;
2125 out_drop_task:
2126 put_task_struct(task);
2127 out:
2128 return ERR_PTR(-ENOENT);
2129 }
2130
2131 #define PROC_NUMBUF 10
2132 #define PROC_MAXPIDS 20
2133
2134 /*
2135 * Get a few tgid's to return for filldir - we need to hold the
2136 * tasklist lock while doing this, and we must release it before
2137 * we actually do the filldir itself, so we use a temp buffer..
2138 */
2139 static int get_tgid_list(int index, unsigned long version, unsigned int *tgids)
2140 {
2141 struct task_struct *p;
2142 int nr_tgids = 0;
2143
2144 index--;
2145 read_lock(&tasklist_lock);
2146 p = NULL;
2147 if (version) {
2148 p = find_task_by_pid(version);
2149 if (p && !thread_group_leader(p))
2150 p = NULL;
2151 }
2152
2153 if (p)
2154 index = 0;
2155 else
2156 p = next_task(&init_task);
2157
2158 for ( ; p != &init_task; p = next_task(p)) {
2159 int tgid = p->pid;
2160 if (!pid_alive(p))
2161 continue;
2162 if (--index >= 0)
2163 continue;
2164 tgids[nr_tgids] = tgid;
2165 nr_tgids++;
2166 if (nr_tgids >= PROC_MAXPIDS)
2167 break;
2168 }
2169 read_unlock(&tasklist_lock);
2170 return nr_tgids;
2171 }
2172
2173 /*
2174 * Get a few tid's to return for filldir - we need to hold the
2175 * tasklist lock while doing this, and we must release it before
2176 * we actually do the filldir itself, so we use a temp buffer..
2177 */
2178 static int get_tid_list(int index, unsigned int *tids, struct inode *dir)
2179 {
2180 struct task_struct *leader_task = proc_task(dir);
2181 struct task_struct *task = leader_task;
2182 int nr_tids = 0;
2183
2184 index -= 2;
2185 read_lock(&tasklist_lock);
2186 /*
2187 * The starting point task (leader_task) might be an already
2188 * unlinked task, which cannot be used to access the task-list
2189 * via next_thread().
2190 */
2191 if (pid_alive(task)) do {
2192 int tid = task->pid;
2193
2194 if (--index >= 0)
2195 continue;
2196 if (tids != NULL)
2197 tids[nr_tids] = tid;
2198 nr_tids++;
2199 if (nr_tids >= PROC_MAXPIDS)
2200 break;
2201 } while ((task = next_thread(task)) != leader_task);
2202 read_unlock(&tasklist_lock);
2203 return nr_tids;
2204 }
2205
2206 /* for the /proc/ directory itself, after non-process stuff has been done */
2207 int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
2208 {
2209 unsigned int tgid_array[PROC_MAXPIDS];
2210 char buf[PROC_NUMBUF];
2211 unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY;
2212 unsigned int nr_tgids, i;
2213 int next_tgid;
2214
2215 if (!nr) {
2216 ino_t ino = fake_ino(0,PROC_TGID_INO);
2217 if (filldir(dirent, "self", 4, filp->f_pos, ino, DT_LNK) < 0)
2218 return 0;
2219 filp->f_pos++;
2220 nr++;
2221 }
2222
2223 /* f_version caches the tgid value that the last readdir call couldn't
2224 * return. lseek aka telldir automagically resets f_version to 0.
2225 */
2226 next_tgid = filp->f_version;
2227 filp->f_version = 0;
2228 for (;;) {
2229 nr_tgids = get_tgid_list(nr, next_tgid, tgid_array);
2230 if (!nr_tgids) {
2231 /* no more entries ! */
2232 break;
2233 }
2234 next_tgid = 0;
2235
2236 /* do not use the last found pid, reserve it for next_tgid */
2237 if (nr_tgids == PROC_MAXPIDS) {
2238 nr_tgids--;
2239 next_tgid = tgid_array[nr_tgids];
2240 }
2241
2242 for (i=0;i<nr_tgids;i++) {
2243 int tgid = tgid_array[i];
2244 ino_t ino = fake_ino(tgid,PROC_TGID_INO);
2245 unsigned long j = PROC_NUMBUF;
2246
2247 do
2248 buf[--j] = '0' + (tgid % 10);
2249 while ((tgid /= 10) != 0);
2250
2251 if (filldir(dirent, buf+j, PROC_NUMBUF-j, filp->f_pos, ino, DT_DIR) < 0) {
2252 /* returning this tgid failed, save it as the first
2253 * pid for the next readir call */
2254 filp->f_version = tgid_array[i];
2255 goto out;
2256 }
2257 filp->f_pos++;
2258 nr++;
2259 }
2260 }
2261 out:
2262 return 0;
2263 }
2264
2265 /* for the /proc/TGID/task/ directories */
2266 static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir)
2267 {
2268 unsigned int tid_array[PROC_MAXPIDS];
2269 char buf[PROC_NUMBUF];
2270 unsigned int nr_tids, i;
2271 struct dentry *dentry = filp->f_dentry;
2272 struct inode *inode = dentry->d_inode;
2273 int retval = -ENOENT;
2274 ino_t ino;
2275 unsigned long pos = filp->f_pos; /* avoiding "long long" filp->f_pos */
2276
2277 if (!pid_alive(proc_task(inode)))
2278 goto out;
2279 retval = 0;
2280
2281 switch (pos) {
2282 case 0:
2283 ino = inode->i_ino;
2284 if (filldir(dirent, ".", 1, pos, ino, DT_DIR) < 0)
2285 goto out;
2286 pos++;
2287 /* fall through */
2288 case 1:
2289 ino = parent_ino(dentry);
2290 if (filldir(dirent, "..", 2, pos, ino, DT_DIR) < 0)
2291 goto out;
2292 pos++;
2293 /* fall through */
2294 }
2295
2296 nr_tids = get_tid_list(pos, tid_array, inode);
2297 inode->i_nlink = pos + nr_tids;
2298
2299 for (i = 0; i < nr_tids; i++) {
2300 unsigned long j = PROC_NUMBUF;
2301 int tid = tid_array[i];
2302
2303 ino = fake_ino(tid,PROC_TID_INO);
2304
2305 do
2306 buf[--j] = '0' + (tid % 10);
2307 while ((tid /= 10) != 0);
2308
2309 if (filldir(dirent, buf+j, PROC_NUMBUF-j, pos, ino, DT_DIR) < 0)
2310 break;
2311 pos++;
2312 }
2313 out:
2314 filp->f_pos = pos;
2315 return retval;
2316 }
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