Commit | Line | Data |
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1da177e4 LT |
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. | |
e070ad49 ML |
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. | |
1da177e4 LT |
48 | */ |
49 | ||
50 | #include <asm/uaccess.h> | |
51 | ||
1da177e4 LT |
52 | #include <linux/errno.h> |
53 | #include <linux/time.h> | |
54 | #include <linux/proc_fs.h> | |
55 | #include <linux/stat.h> | |
56 | #include <linux/init.h> | |
16f7e0fe | 57 | #include <linux/capability.h> |
1da177e4 LT |
58 | #include <linux/file.h> |
59 | #include <linux/string.h> | |
60 | #include <linux/seq_file.h> | |
61 | #include <linux/namei.h> | |
62 | #include <linux/namespace.h> | |
63 | #include <linux/mm.h> | |
64 | #include <linux/smp_lock.h> | |
b835996f | 65 | #include <linux/rcupdate.h> |
1da177e4 LT |
66 | #include <linux/kallsyms.h> |
67 | #include <linux/mount.h> | |
68 | #include <linux/security.h> | |
69 | #include <linux/ptrace.h> | |
70 | #include <linux/seccomp.h> | |
71 | #include <linux/cpuset.h> | |
72 | #include <linux/audit.h> | |
5addc5dd | 73 | #include <linux/poll.h> |
1651e14e | 74 | #include <linux/nsproxy.h> |
8ac773b4 | 75 | #include <linux/oom.h> |
1da177e4 LT |
76 | #include "internal.h" |
77 | ||
0f2fe20f EB |
78 | /* NOTE: |
79 | * Implementing inode permission operations in /proc is almost | |
80 | * certainly an error. Permission checks need to happen during | |
81 | * each system call not at open time. The reason is that most of | |
82 | * what we wish to check for permissions in /proc varies at runtime. | |
83 | * | |
84 | * The classic example of a problem is opening file descriptors | |
85 | * in /proc for a task before it execs a suid executable. | |
86 | */ | |
87 | ||
1da177e4 | 88 | |
8578cea7 | 89 | /* Worst case buffer size needed for holding an integer. */ |
0187f879 | 90 | #define PROC_NUMBUF 13 |
8578cea7 | 91 | |
1da177e4 | 92 | struct pid_entry { |
1da177e4 LT |
93 | int len; |
94 | char *name; | |
95 | mode_t mode; | |
20cdc894 EB |
96 | struct inode_operations *iop; |
97 | struct file_operations *fop; | |
98 | union proc_op op; | |
1da177e4 LT |
99 | }; |
100 | ||
61a28784 | 101 | #define NOD(NAME, MODE, IOP, FOP, OP) { \ |
20cdc894 EB |
102 | .len = sizeof(NAME) - 1, \ |
103 | .name = (NAME), \ | |
104 | .mode = MODE, \ | |
105 | .iop = IOP, \ | |
106 | .fop = FOP, \ | |
107 | .op = OP, \ | |
108 | } | |
109 | ||
61a28784 EB |
110 | #define DIR(NAME, MODE, OTYPE) \ |
111 | NOD(NAME, (S_IFDIR|(MODE)), \ | |
20cdc894 EB |
112 | &proc_##OTYPE##_inode_operations, &proc_##OTYPE##_operations, \ |
113 | {} ) | |
61a28784 EB |
114 | #define LNK(NAME, OTYPE) \ |
115 | NOD(NAME, (S_IFLNK|S_IRWXUGO), \ | |
20cdc894 EB |
116 | &proc_pid_link_inode_operations, NULL, \ |
117 | { .proc_get_link = &proc_##OTYPE##_link } ) | |
61a28784 EB |
118 | #define REG(NAME, MODE, OTYPE) \ |
119 | NOD(NAME, (S_IFREG|(MODE)), NULL, \ | |
20cdc894 | 120 | &proc_##OTYPE##_operations, {}) |
61a28784 EB |
121 | #define INF(NAME, MODE, OTYPE) \ |
122 | NOD(NAME, (S_IFREG|(MODE)), \ | |
20cdc894 EB |
123 | NULL, &proc_info_file_operations, \ |
124 | { .proc_read = &proc_##OTYPE } ) | |
1da177e4 | 125 | |
0494f6ec | 126 | static struct fs_struct *get_fs_struct(struct task_struct *task) |
1da177e4 LT |
127 | { |
128 | struct fs_struct *fs; | |
0494f6ec MS |
129 | task_lock(task); |
130 | fs = task->fs; | |
1da177e4 LT |
131 | if(fs) |
132 | atomic_inc(&fs->count); | |
0494f6ec MS |
133 | task_unlock(task); |
134 | return fs; | |
135 | } | |
136 | ||
99f89551 EB |
137 | static int get_nr_threads(struct task_struct *tsk) |
138 | { | |
139 | /* Must be called with the rcu_read_lock held */ | |
140 | unsigned long flags; | |
141 | int count = 0; | |
142 | ||
143 | if (lock_task_sighand(tsk, &flags)) { | |
144 | count = atomic_read(&tsk->signal->count); | |
145 | unlock_task_sighand(tsk, &flags); | |
146 | } | |
147 | return count; | |
148 | } | |
149 | ||
0494f6ec MS |
150 | static int proc_cwd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt) |
151 | { | |
99f89551 EB |
152 | struct task_struct *task = get_proc_task(inode); |
153 | struct fs_struct *fs = NULL; | |
0494f6ec | 154 | int result = -ENOENT; |
99f89551 EB |
155 | |
156 | if (task) { | |
157 | fs = get_fs_struct(task); | |
158 | put_task_struct(task); | |
159 | } | |
1da177e4 LT |
160 | if (fs) { |
161 | read_lock(&fs->lock); | |
162 | *mnt = mntget(fs->pwdmnt); | |
163 | *dentry = dget(fs->pwd); | |
164 | read_unlock(&fs->lock); | |
165 | result = 0; | |
166 | put_fs_struct(fs); | |
167 | } | |
168 | return result; | |
169 | } | |
170 | ||
171 | static int proc_root_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt) | |
172 | { | |
99f89551 EB |
173 | struct task_struct *task = get_proc_task(inode); |
174 | struct fs_struct *fs = NULL; | |
1da177e4 | 175 | int result = -ENOENT; |
99f89551 EB |
176 | |
177 | if (task) { | |
178 | fs = get_fs_struct(task); | |
179 | put_task_struct(task); | |
180 | } | |
1da177e4 LT |
181 | if (fs) { |
182 | read_lock(&fs->lock); | |
183 | *mnt = mntget(fs->rootmnt); | |
184 | *dentry = dget(fs->root); | |
185 | read_unlock(&fs->lock); | |
186 | result = 0; | |
187 | put_fs_struct(fs); | |
188 | } | |
189 | return result; | |
190 | } | |
191 | ||
192 | #define MAY_PTRACE(task) \ | |
193 | (task == current || \ | |
194 | (task->parent == current && \ | |
195 | (task->ptrace & PT_PTRACED) && \ | |
196 | (task->state == TASK_STOPPED || task->state == TASK_TRACED) && \ | |
197 | security_ptrace(current,task) == 0)) | |
198 | ||
1da177e4 LT |
199 | static int proc_pid_environ(struct task_struct *task, char * buffer) |
200 | { | |
201 | int res = 0; | |
202 | struct mm_struct *mm = get_task_mm(task); | |
203 | if (mm) { | |
204 | unsigned int len = mm->env_end - mm->env_start; | |
205 | if (len > PAGE_SIZE) | |
206 | len = PAGE_SIZE; | |
207 | res = access_process_vm(task, mm->env_start, buffer, len, 0); | |
ab8d11be | 208 | if (!ptrace_may_attach(task)) |
1da177e4 LT |
209 | res = -ESRCH; |
210 | mmput(mm); | |
211 | } | |
212 | return res; | |
213 | } | |
214 | ||
215 | static int proc_pid_cmdline(struct task_struct *task, char * buffer) | |
216 | { | |
217 | int res = 0; | |
218 | unsigned int len; | |
219 | struct mm_struct *mm = get_task_mm(task); | |
220 | if (!mm) | |
221 | goto out; | |
222 | if (!mm->arg_end) | |
223 | goto out_mm; /* Shh! No looking before we're done */ | |
224 | ||
225 | len = mm->arg_end - mm->arg_start; | |
226 | ||
227 | if (len > PAGE_SIZE) | |
228 | len = PAGE_SIZE; | |
229 | ||
230 | res = access_process_vm(task, mm->arg_start, buffer, len, 0); | |
231 | ||
232 | // If the nul at the end of args has been overwritten, then | |
233 | // assume application is using setproctitle(3). | |
234 | if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) { | |
235 | len = strnlen(buffer, res); | |
236 | if (len < res) { | |
237 | res = len; | |
238 | } else { | |
239 | len = mm->env_end - mm->env_start; | |
240 | if (len > PAGE_SIZE - res) | |
241 | len = PAGE_SIZE - res; | |
242 | res += access_process_vm(task, mm->env_start, buffer+res, len, 0); | |
243 | res = strnlen(buffer, res); | |
244 | } | |
245 | } | |
246 | out_mm: | |
247 | mmput(mm); | |
248 | out: | |
249 | return res; | |
250 | } | |
251 | ||
252 | static int proc_pid_auxv(struct task_struct *task, char *buffer) | |
253 | { | |
254 | int res = 0; | |
255 | struct mm_struct *mm = get_task_mm(task); | |
256 | if (mm) { | |
257 | unsigned int nwords = 0; | |
258 | do | |
259 | nwords += 2; | |
260 | while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */ | |
261 | res = nwords * sizeof(mm->saved_auxv[0]); | |
262 | if (res > PAGE_SIZE) | |
263 | res = PAGE_SIZE; | |
264 | memcpy(buffer, mm->saved_auxv, res); | |
265 | mmput(mm); | |
266 | } | |
267 | return res; | |
268 | } | |
269 | ||
270 | ||
271 | #ifdef CONFIG_KALLSYMS | |
272 | /* | |
273 | * Provides a wchan file via kallsyms in a proper one-value-per-file format. | |
274 | * Returns the resolved symbol. If that fails, simply return the address. | |
275 | */ | |
276 | static int proc_pid_wchan(struct task_struct *task, char *buffer) | |
277 | { | |
278 | char *modname; | |
279 | const char *sym_name; | |
280 | unsigned long wchan, size, offset; | |
281 | char namebuf[KSYM_NAME_LEN+1]; | |
282 | ||
283 | wchan = get_wchan(task); | |
284 | ||
285 | sym_name = kallsyms_lookup(wchan, &size, &offset, &modname, namebuf); | |
286 | if (sym_name) | |
287 | return sprintf(buffer, "%s", sym_name); | |
288 | return sprintf(buffer, "%lu", wchan); | |
289 | } | |
290 | #endif /* CONFIG_KALLSYMS */ | |
291 | ||
292 | #ifdef CONFIG_SCHEDSTATS | |
293 | /* | |
294 | * Provides /proc/PID/schedstat | |
295 | */ | |
296 | static int proc_pid_schedstat(struct task_struct *task, char *buffer) | |
297 | { | |
298 | return sprintf(buffer, "%lu %lu %lu\n", | |
299 | task->sched_info.cpu_time, | |
300 | task->sched_info.run_delay, | |
301 | task->sched_info.pcnt); | |
302 | } | |
303 | #endif | |
304 | ||
305 | /* The badness from the OOM killer */ | |
306 | unsigned long badness(struct task_struct *p, unsigned long uptime); | |
307 | static int proc_oom_score(struct task_struct *task, char *buffer) | |
308 | { | |
309 | unsigned long points; | |
310 | struct timespec uptime; | |
311 | ||
312 | do_posix_clock_monotonic_gettime(&uptime); | |
313 | points = badness(task, uptime.tv_sec); | |
314 | return sprintf(buffer, "%lu\n", points); | |
315 | } | |
316 | ||
317 | /************************************************************************/ | |
318 | /* Here the fs part begins */ | |
319 | /************************************************************************/ | |
320 | ||
321 | /* permission checks */ | |
778c1144 | 322 | static int proc_fd_access_allowed(struct inode *inode) |
1da177e4 | 323 | { |
778c1144 EB |
324 | struct task_struct *task; |
325 | int allowed = 0; | |
df26c40e EB |
326 | /* Allow access to a task's file descriptors if it is us or we |
327 | * may use ptrace attach to the process and find out that | |
328 | * information. | |
778c1144 EB |
329 | */ |
330 | task = get_proc_task(inode); | |
df26c40e EB |
331 | if (task) { |
332 | allowed = ptrace_may_attach(task); | |
778c1144 | 333 | put_task_struct(task); |
df26c40e | 334 | } |
778c1144 | 335 | return allowed; |
1da177e4 LT |
336 | } |
337 | ||
6d76fa58 LT |
338 | static int proc_setattr(struct dentry *dentry, struct iattr *attr) |
339 | { | |
340 | int error; | |
341 | struct inode *inode = dentry->d_inode; | |
342 | ||
343 | if (attr->ia_valid & ATTR_MODE) | |
344 | return -EPERM; | |
345 | ||
346 | error = inode_change_ok(inode, attr); | |
347 | if (!error) { | |
348 | error = security_inode_setattr(dentry, attr); | |
349 | if (!error) | |
350 | error = inode_setattr(inode, attr); | |
351 | } | |
352 | return error; | |
353 | } | |
354 | ||
355 | static struct inode_operations proc_def_inode_operations = { | |
356 | .setattr = proc_setattr, | |
357 | }; | |
358 | ||
1da177e4 | 359 | extern struct seq_operations mounts_op; |
5addc5dd AV |
360 | struct proc_mounts { |
361 | struct seq_file m; | |
362 | int event; | |
363 | }; | |
364 | ||
1da177e4 LT |
365 | static int mounts_open(struct inode *inode, struct file *file) |
366 | { | |
99f89551 EB |
367 | struct task_struct *task = get_proc_task(inode); |
368 | struct namespace *namespace = NULL; | |
5addc5dd AV |
369 | struct proc_mounts *p; |
370 | int ret = -EINVAL; | |
1da177e4 | 371 | |
99f89551 EB |
372 | if (task) { |
373 | task_lock(task); | |
1651e14e | 374 | namespace = task->nsproxy->namespace; |
99f89551 EB |
375 | if (namespace) |
376 | get_namespace(namespace); | |
377 | task_unlock(task); | |
378 | put_task_struct(task); | |
379 | } | |
5addc5dd AV |
380 | |
381 | if (namespace) { | |
382 | ret = -ENOMEM; | |
383 | p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL); | |
384 | if (p) { | |
385 | file->private_data = &p->m; | |
386 | ret = seq_open(file, &mounts_op); | |
387 | if (!ret) { | |
388 | p->m.private = namespace; | |
389 | p->event = namespace->event; | |
390 | return 0; | |
391 | } | |
392 | kfree(p); | |
1da177e4 | 393 | } |
5addc5dd | 394 | put_namespace(namespace); |
1da177e4 LT |
395 | } |
396 | return ret; | |
397 | } | |
398 | ||
399 | static int mounts_release(struct inode *inode, struct file *file) | |
400 | { | |
401 | struct seq_file *m = file->private_data; | |
402 | struct namespace *namespace = m->private; | |
403 | put_namespace(namespace); | |
404 | return seq_release(inode, file); | |
405 | } | |
406 | ||
5addc5dd AV |
407 | static unsigned mounts_poll(struct file *file, poll_table *wait) |
408 | { | |
409 | struct proc_mounts *p = file->private_data; | |
410 | struct namespace *ns = p->m.private; | |
411 | unsigned res = 0; | |
412 | ||
413 | poll_wait(file, &ns->poll, wait); | |
414 | ||
415 | spin_lock(&vfsmount_lock); | |
416 | if (p->event != ns->event) { | |
417 | p->event = ns->event; | |
418 | res = POLLERR; | |
419 | } | |
420 | spin_unlock(&vfsmount_lock); | |
421 | ||
422 | return res; | |
423 | } | |
424 | ||
1da177e4 LT |
425 | static struct file_operations proc_mounts_operations = { |
426 | .open = mounts_open, | |
427 | .read = seq_read, | |
428 | .llseek = seq_lseek, | |
429 | .release = mounts_release, | |
5addc5dd | 430 | .poll = mounts_poll, |
1da177e4 LT |
431 | }; |
432 | ||
b4629fe2 CL |
433 | extern struct seq_operations mountstats_op; |
434 | static int mountstats_open(struct inode *inode, struct file *file) | |
435 | { | |
b4629fe2 CL |
436 | int ret = seq_open(file, &mountstats_op); |
437 | ||
438 | if (!ret) { | |
439 | struct seq_file *m = file->private_data; | |
99f89551 EB |
440 | struct namespace *namespace = NULL; |
441 | struct task_struct *task = get_proc_task(inode); | |
442 | ||
443 | if (task) { | |
444 | task_lock(task); | |
701e054e VT |
445 | if (task->nsproxy) |
446 | namespace = task->nsproxy->namespace; | |
99f89551 EB |
447 | if (namespace) |
448 | get_namespace(namespace); | |
449 | task_unlock(task); | |
450 | put_task_struct(task); | |
451 | } | |
b4629fe2 CL |
452 | |
453 | if (namespace) | |
454 | m->private = namespace; | |
455 | else { | |
456 | seq_release(inode, file); | |
457 | ret = -EINVAL; | |
458 | } | |
459 | } | |
460 | return ret; | |
461 | } | |
462 | ||
463 | static struct file_operations proc_mountstats_operations = { | |
464 | .open = mountstats_open, | |
465 | .read = seq_read, | |
466 | .llseek = seq_lseek, | |
467 | .release = mounts_release, | |
468 | }; | |
469 | ||
1da177e4 LT |
470 | #define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */ |
471 | ||
472 | static ssize_t proc_info_read(struct file * file, char __user * buf, | |
473 | size_t count, loff_t *ppos) | |
474 | { | |
475 | struct inode * inode = file->f_dentry->d_inode; | |
476 | unsigned long page; | |
477 | ssize_t length; | |
99f89551 EB |
478 | struct task_struct *task = get_proc_task(inode); |
479 | ||
480 | length = -ESRCH; | |
481 | if (!task) | |
482 | goto out_no_task; | |
1da177e4 LT |
483 | |
484 | if (count > PROC_BLOCK_SIZE) | |
485 | count = PROC_BLOCK_SIZE; | |
99f89551 EB |
486 | |
487 | length = -ENOMEM; | |
1da177e4 | 488 | if (!(page = __get_free_page(GFP_KERNEL))) |
99f89551 | 489 | goto out; |
1da177e4 LT |
490 | |
491 | length = PROC_I(inode)->op.proc_read(task, (char*)page); | |
492 | ||
493 | if (length >= 0) | |
494 | length = simple_read_from_buffer(buf, count, ppos, (char *)page, length); | |
495 | free_page(page); | |
99f89551 EB |
496 | out: |
497 | put_task_struct(task); | |
498 | out_no_task: | |
1da177e4 LT |
499 | return length; |
500 | } | |
501 | ||
502 | static struct file_operations proc_info_file_operations = { | |
503 | .read = proc_info_read, | |
504 | }; | |
505 | ||
506 | static int mem_open(struct inode* inode, struct file* file) | |
507 | { | |
508 | file->private_data = (void*)((long)current->self_exec_id); | |
509 | return 0; | |
510 | } | |
511 | ||
512 | static ssize_t mem_read(struct file * file, char __user * buf, | |
513 | size_t count, loff_t *ppos) | |
514 | { | |
99f89551 | 515 | struct task_struct *task = get_proc_task(file->f_dentry->d_inode); |
1da177e4 LT |
516 | char *page; |
517 | unsigned long src = *ppos; | |
518 | int ret = -ESRCH; | |
519 | struct mm_struct *mm; | |
520 | ||
99f89551 EB |
521 | if (!task) |
522 | goto out_no_task; | |
523 | ||
ab8d11be | 524 | if (!MAY_PTRACE(task) || !ptrace_may_attach(task)) |
1da177e4 LT |
525 | goto out; |
526 | ||
527 | ret = -ENOMEM; | |
528 | page = (char *)__get_free_page(GFP_USER); | |
529 | if (!page) | |
530 | goto out; | |
531 | ||
532 | ret = 0; | |
533 | ||
534 | mm = get_task_mm(task); | |
535 | if (!mm) | |
536 | goto out_free; | |
537 | ||
538 | ret = -EIO; | |
539 | ||
540 | if (file->private_data != (void*)((long)current->self_exec_id)) | |
541 | goto out_put; | |
542 | ||
543 | ret = 0; | |
544 | ||
545 | while (count > 0) { | |
546 | int this_len, retval; | |
547 | ||
548 | this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; | |
549 | retval = access_process_vm(task, src, page, this_len, 0); | |
ab8d11be | 550 | if (!retval || !MAY_PTRACE(task) || !ptrace_may_attach(task)) { |
1da177e4 LT |
551 | if (!ret) |
552 | ret = -EIO; | |
553 | break; | |
554 | } | |
555 | ||
556 | if (copy_to_user(buf, page, retval)) { | |
557 | ret = -EFAULT; | |
558 | break; | |
559 | } | |
560 | ||
561 | ret += retval; | |
562 | src += retval; | |
563 | buf += retval; | |
564 | count -= retval; | |
565 | } | |
566 | *ppos = src; | |
567 | ||
568 | out_put: | |
569 | mmput(mm); | |
570 | out_free: | |
571 | free_page((unsigned long) page); | |
572 | out: | |
99f89551 EB |
573 | put_task_struct(task); |
574 | out_no_task: | |
1da177e4 LT |
575 | return ret; |
576 | } | |
577 | ||
578 | #define mem_write NULL | |
579 | ||
580 | #ifndef mem_write | |
581 | /* This is a security hazard */ | |
582 | static ssize_t mem_write(struct file * file, const char * buf, | |
583 | size_t count, loff_t *ppos) | |
584 | { | |
f7ca54f4 | 585 | int copied; |
1da177e4 | 586 | char *page; |
99f89551 | 587 | struct task_struct *task = get_proc_task(file->f_dentry->d_inode); |
1da177e4 LT |
588 | unsigned long dst = *ppos; |
589 | ||
99f89551 EB |
590 | copied = -ESRCH; |
591 | if (!task) | |
592 | goto out_no_task; | |
593 | ||
ab8d11be | 594 | if (!MAY_PTRACE(task) || !ptrace_may_attach(task)) |
99f89551 | 595 | goto out; |
1da177e4 | 596 | |
99f89551 | 597 | copied = -ENOMEM; |
1da177e4 LT |
598 | page = (char *)__get_free_page(GFP_USER); |
599 | if (!page) | |
99f89551 | 600 | goto out; |
1da177e4 | 601 | |
f7ca54f4 | 602 | copied = 0; |
1da177e4 LT |
603 | while (count > 0) { |
604 | int this_len, retval; | |
605 | ||
606 | this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; | |
607 | if (copy_from_user(page, buf, this_len)) { | |
608 | copied = -EFAULT; | |
609 | break; | |
610 | } | |
611 | retval = access_process_vm(task, dst, page, this_len, 1); | |
612 | if (!retval) { | |
613 | if (!copied) | |
614 | copied = -EIO; | |
615 | break; | |
616 | } | |
617 | copied += retval; | |
618 | buf += retval; | |
619 | dst += retval; | |
620 | count -= retval; | |
621 | } | |
622 | *ppos = dst; | |
623 | free_page((unsigned long) page); | |
99f89551 EB |
624 | out: |
625 | put_task_struct(task); | |
626 | out_no_task: | |
1da177e4 LT |
627 | return copied; |
628 | } | |
629 | #endif | |
630 | ||
631 | static loff_t mem_lseek(struct file * file, loff_t offset, int orig) | |
632 | { | |
633 | switch (orig) { | |
634 | case 0: | |
635 | file->f_pos = offset; | |
636 | break; | |
637 | case 1: | |
638 | file->f_pos += offset; | |
639 | break; | |
640 | default: | |
641 | return -EINVAL; | |
642 | } | |
643 | force_successful_syscall_return(); | |
644 | return file->f_pos; | |
645 | } | |
646 | ||
647 | static struct file_operations proc_mem_operations = { | |
648 | .llseek = mem_lseek, | |
649 | .read = mem_read, | |
650 | .write = mem_write, | |
651 | .open = mem_open, | |
652 | }; | |
653 | ||
654 | static ssize_t oom_adjust_read(struct file *file, char __user *buf, | |
655 | size_t count, loff_t *ppos) | |
656 | { | |
99f89551 | 657 | struct task_struct *task = get_proc_task(file->f_dentry->d_inode); |
8578cea7 | 658 | char buffer[PROC_NUMBUF]; |
1da177e4 | 659 | size_t len; |
99f89551 | 660 | int oom_adjust; |
1da177e4 LT |
661 | loff_t __ppos = *ppos; |
662 | ||
99f89551 EB |
663 | if (!task) |
664 | return -ESRCH; | |
665 | oom_adjust = task->oomkilladj; | |
666 | put_task_struct(task); | |
667 | ||
8578cea7 | 668 | len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust); |
1da177e4 LT |
669 | if (__ppos >= len) |
670 | return 0; | |
671 | if (count > len-__ppos) | |
672 | count = len-__ppos; | |
673 | if (copy_to_user(buf, buffer + __ppos, count)) | |
674 | return -EFAULT; | |
675 | *ppos = __ppos + count; | |
676 | return count; | |
677 | } | |
678 | ||
679 | static ssize_t oom_adjust_write(struct file *file, const char __user *buf, | |
680 | size_t count, loff_t *ppos) | |
681 | { | |
99f89551 | 682 | struct task_struct *task; |
8578cea7 | 683 | char buffer[PROC_NUMBUF], *end; |
1da177e4 LT |
684 | int oom_adjust; |
685 | ||
686 | if (!capable(CAP_SYS_RESOURCE)) | |
687 | return -EPERM; | |
8578cea7 EB |
688 | memset(buffer, 0, sizeof(buffer)); |
689 | if (count > sizeof(buffer) - 1) | |
690 | count = sizeof(buffer) - 1; | |
1da177e4 LT |
691 | if (copy_from_user(buffer, buf, count)) |
692 | return -EFAULT; | |
693 | oom_adjust = simple_strtol(buffer, &end, 0); | |
8ac773b4 AD |
694 | if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) && |
695 | oom_adjust != OOM_DISABLE) | |
1da177e4 LT |
696 | return -EINVAL; |
697 | if (*end == '\n') | |
698 | end++; | |
99f89551 EB |
699 | task = get_proc_task(file->f_dentry->d_inode); |
700 | if (!task) | |
701 | return -ESRCH; | |
1da177e4 | 702 | task->oomkilladj = oom_adjust; |
99f89551 | 703 | put_task_struct(task); |
1da177e4 LT |
704 | if (end - buffer == 0) |
705 | return -EIO; | |
706 | return end - buffer; | |
707 | } | |
708 | ||
709 | static struct file_operations proc_oom_adjust_operations = { | |
710 | .read = oom_adjust_read, | |
711 | .write = oom_adjust_write, | |
712 | }; | |
713 | ||
1da177e4 LT |
714 | #ifdef CONFIG_AUDITSYSCALL |
715 | #define TMPBUFLEN 21 | |
716 | static ssize_t proc_loginuid_read(struct file * file, char __user * buf, | |
717 | size_t count, loff_t *ppos) | |
718 | { | |
719 | struct inode * inode = file->f_dentry->d_inode; | |
99f89551 | 720 | struct task_struct *task = get_proc_task(inode); |
1da177e4 LT |
721 | ssize_t length; |
722 | char tmpbuf[TMPBUFLEN]; | |
723 | ||
99f89551 EB |
724 | if (!task) |
725 | return -ESRCH; | |
1da177e4 LT |
726 | length = scnprintf(tmpbuf, TMPBUFLEN, "%u", |
727 | audit_get_loginuid(task->audit_context)); | |
99f89551 | 728 | put_task_struct(task); |
1da177e4 LT |
729 | return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); |
730 | } | |
731 | ||
732 | static ssize_t proc_loginuid_write(struct file * file, const char __user * buf, | |
733 | size_t count, loff_t *ppos) | |
734 | { | |
735 | struct inode * inode = file->f_dentry->d_inode; | |
736 | char *page, *tmp; | |
737 | ssize_t length; | |
1da177e4 LT |
738 | uid_t loginuid; |
739 | ||
740 | if (!capable(CAP_AUDIT_CONTROL)) | |
741 | return -EPERM; | |
742 | ||
13b41b09 | 743 | if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) |
1da177e4 LT |
744 | return -EPERM; |
745 | ||
e0182909 AV |
746 | if (count >= PAGE_SIZE) |
747 | count = PAGE_SIZE - 1; | |
1da177e4 LT |
748 | |
749 | if (*ppos != 0) { | |
750 | /* No partial writes. */ | |
751 | return -EINVAL; | |
752 | } | |
753 | page = (char*)__get_free_page(GFP_USER); | |
754 | if (!page) | |
755 | return -ENOMEM; | |
756 | length = -EFAULT; | |
757 | if (copy_from_user(page, buf, count)) | |
758 | goto out_free_page; | |
759 | ||
e0182909 | 760 | page[count] = '\0'; |
1da177e4 LT |
761 | loginuid = simple_strtoul(page, &tmp, 10); |
762 | if (tmp == page) { | |
763 | length = -EINVAL; | |
764 | goto out_free_page; | |
765 | ||
766 | } | |
99f89551 | 767 | length = audit_set_loginuid(current, loginuid); |
1da177e4 LT |
768 | if (likely(length == 0)) |
769 | length = count; | |
770 | ||
771 | out_free_page: | |
772 | free_page((unsigned long) page); | |
773 | return length; | |
774 | } | |
775 | ||
776 | static struct file_operations proc_loginuid_operations = { | |
777 | .read = proc_loginuid_read, | |
778 | .write = proc_loginuid_write, | |
779 | }; | |
780 | #endif | |
781 | ||
782 | #ifdef CONFIG_SECCOMP | |
783 | static ssize_t seccomp_read(struct file *file, char __user *buf, | |
784 | size_t count, loff_t *ppos) | |
785 | { | |
99f89551 | 786 | struct task_struct *tsk = get_proc_task(file->f_dentry->d_inode); |
1da177e4 LT |
787 | char __buf[20]; |
788 | loff_t __ppos = *ppos; | |
789 | size_t len; | |
790 | ||
99f89551 EB |
791 | if (!tsk) |
792 | return -ESRCH; | |
1da177e4 LT |
793 | /* no need to print the trailing zero, so use only len */ |
794 | len = sprintf(__buf, "%u\n", tsk->seccomp.mode); | |
99f89551 | 795 | put_task_struct(tsk); |
1da177e4 LT |
796 | if (__ppos >= len) |
797 | return 0; | |
798 | if (count > len - __ppos) | |
799 | count = len - __ppos; | |
800 | if (copy_to_user(buf, __buf + __ppos, count)) | |
801 | return -EFAULT; | |
802 | *ppos = __ppos + count; | |
803 | return count; | |
804 | } | |
805 | ||
806 | static ssize_t seccomp_write(struct file *file, const char __user *buf, | |
807 | size_t count, loff_t *ppos) | |
808 | { | |
99f89551 | 809 | struct task_struct *tsk = get_proc_task(file->f_dentry->d_inode); |
1da177e4 LT |
810 | char __buf[20], *end; |
811 | unsigned int seccomp_mode; | |
99f89551 EB |
812 | ssize_t result; |
813 | ||
814 | result = -ESRCH; | |
815 | if (!tsk) | |
816 | goto out_no_task; | |
1da177e4 LT |
817 | |
818 | /* can set it only once to be even more secure */ | |
99f89551 | 819 | result = -EPERM; |
1da177e4 | 820 | if (unlikely(tsk->seccomp.mode)) |
99f89551 | 821 | goto out; |
1da177e4 | 822 | |
99f89551 | 823 | result = -EFAULT; |
1da177e4 LT |
824 | memset(__buf, 0, sizeof(__buf)); |
825 | count = min(count, sizeof(__buf) - 1); | |
826 | if (copy_from_user(__buf, buf, count)) | |
99f89551 EB |
827 | goto out; |
828 | ||
1da177e4 LT |
829 | seccomp_mode = simple_strtoul(__buf, &end, 0); |
830 | if (*end == '\n') | |
831 | end++; | |
99f89551 | 832 | result = -EINVAL; |
1da177e4 LT |
833 | if (seccomp_mode && seccomp_mode <= NR_SECCOMP_MODES) { |
834 | tsk->seccomp.mode = seccomp_mode; | |
835 | set_tsk_thread_flag(tsk, TIF_SECCOMP); | |
836 | } else | |
99f89551 EB |
837 | goto out; |
838 | result = -EIO; | |
1da177e4 | 839 | if (unlikely(!(end - __buf))) |
99f89551 EB |
840 | goto out; |
841 | result = end - __buf; | |
842 | out: | |
843 | put_task_struct(tsk); | |
844 | out_no_task: | |
845 | return result; | |
1da177e4 LT |
846 | } |
847 | ||
848 | static struct file_operations proc_seccomp_operations = { | |
849 | .read = seccomp_read, | |
850 | .write = seccomp_write, | |
851 | }; | |
852 | #endif /* CONFIG_SECCOMP */ | |
853 | ||
008b150a | 854 | static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd) |
1da177e4 LT |
855 | { |
856 | struct inode *inode = dentry->d_inode; | |
857 | int error = -EACCES; | |
858 | ||
859 | /* We don't need a base pointer in the /proc filesystem */ | |
860 | path_release(nd); | |
861 | ||
778c1144 EB |
862 | /* Are we allowed to snoop on the tasks file descriptors? */ |
863 | if (!proc_fd_access_allowed(inode)) | |
1da177e4 | 864 | goto out; |
1da177e4 LT |
865 | |
866 | error = PROC_I(inode)->op.proc_get_link(inode, &nd->dentry, &nd->mnt); | |
867 | nd->last_type = LAST_BIND; | |
868 | out: | |
008b150a | 869 | return ERR_PTR(error); |
1da177e4 LT |
870 | } |
871 | ||
872 | static int do_proc_readlink(struct dentry *dentry, struct vfsmount *mnt, | |
873 | char __user *buffer, int buflen) | |
874 | { | |
875 | struct inode * inode; | |
876 | char *tmp = (char*)__get_free_page(GFP_KERNEL), *path; | |
877 | int len; | |
878 | ||
879 | if (!tmp) | |
880 | return -ENOMEM; | |
881 | ||
882 | inode = dentry->d_inode; | |
883 | path = d_path(dentry, mnt, tmp, PAGE_SIZE); | |
884 | len = PTR_ERR(path); | |
885 | if (IS_ERR(path)) | |
886 | goto out; | |
887 | len = tmp + PAGE_SIZE - 1 - path; | |
888 | ||
889 | if (len > buflen) | |
890 | len = buflen; | |
891 | if (copy_to_user(buffer, path, len)) | |
892 | len = -EFAULT; | |
893 | out: | |
894 | free_page((unsigned long)tmp); | |
895 | return len; | |
896 | } | |
897 | ||
898 | static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen) | |
899 | { | |
900 | int error = -EACCES; | |
901 | struct inode *inode = dentry->d_inode; | |
902 | struct dentry *de; | |
903 | struct vfsmount *mnt = NULL; | |
904 | ||
778c1144 EB |
905 | /* Are we allowed to snoop on the tasks file descriptors? */ |
906 | if (!proc_fd_access_allowed(inode)) | |
1da177e4 | 907 | goto out; |
1da177e4 LT |
908 | |
909 | error = PROC_I(inode)->op.proc_get_link(inode, &de, &mnt); | |
910 | if (error) | |
911 | goto out; | |
912 | ||
913 | error = do_proc_readlink(de, mnt, buffer, buflen); | |
914 | dput(de); | |
915 | mntput(mnt); | |
916 | out: | |
1da177e4 LT |
917 | return error; |
918 | } | |
919 | ||
920 | static struct inode_operations proc_pid_link_inode_operations = { | |
921 | .readlink = proc_pid_readlink, | |
6d76fa58 LT |
922 | .follow_link = proc_pid_follow_link, |
923 | .setattr = proc_setattr, | |
1da177e4 LT |
924 | }; |
925 | ||
28a6d671 EB |
926 | |
927 | /* building an inode */ | |
928 | ||
929 | static int task_dumpable(struct task_struct *task) | |
1da177e4 | 930 | { |
28a6d671 EB |
931 | int dumpable = 0; |
932 | struct mm_struct *mm; | |
1da177e4 | 933 | |
28a6d671 EB |
934 | task_lock(task); |
935 | mm = task->mm; | |
936 | if (mm) | |
937 | dumpable = mm->dumpable; | |
938 | task_unlock(task); | |
939 | if(dumpable == 1) | |
940 | return 1; | |
941 | return 0; | |
942 | } | |
1da177e4 | 943 | |
1da177e4 | 944 | |
61a28784 | 945 | static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task) |
28a6d671 EB |
946 | { |
947 | struct inode * inode; | |
948 | struct proc_inode *ei; | |
1da177e4 | 949 | |
28a6d671 | 950 | /* We need a new inode */ |
1da177e4 | 951 | |
28a6d671 EB |
952 | inode = new_inode(sb); |
953 | if (!inode) | |
954 | goto out; | |
955 | ||
956 | /* Common stuff */ | |
957 | ei = PROC_I(inode); | |
958 | inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; | |
28a6d671 EB |
959 | inode->i_op = &proc_def_inode_operations; |
960 | ||
961 | /* | |
962 | * grab the reference to task. | |
963 | */ | |
1a657f78 | 964 | ei->pid = get_task_pid(task, PIDTYPE_PID); |
28a6d671 EB |
965 | if (!ei->pid) |
966 | goto out_unlock; | |
967 | ||
968 | inode->i_uid = 0; | |
969 | inode->i_gid = 0; | |
970 | if (task_dumpable(task)) { | |
971 | inode->i_uid = task->euid; | |
972 | inode->i_gid = task->egid; | |
1da177e4 | 973 | } |
28a6d671 EB |
974 | security_task_to_inode(task, inode); |
975 | ||
1da177e4 | 976 | out: |
28a6d671 EB |
977 | return inode; |
978 | ||
979 | out_unlock: | |
980 | iput(inode); | |
981 | return NULL; | |
1da177e4 LT |
982 | } |
983 | ||
28a6d671 | 984 | static int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) |
1da177e4 | 985 | { |
1da177e4 | 986 | struct inode *inode = dentry->d_inode; |
28a6d671 EB |
987 | struct task_struct *task; |
988 | generic_fillattr(inode, stat); | |
1da177e4 | 989 | |
28a6d671 EB |
990 | rcu_read_lock(); |
991 | stat->uid = 0; | |
992 | stat->gid = 0; | |
993 | task = pid_task(proc_pid(inode), PIDTYPE_PID); | |
994 | if (task) { | |
995 | if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || | |
996 | task_dumpable(task)) { | |
997 | stat->uid = task->euid; | |
998 | stat->gid = task->egid; | |
1da177e4 LT |
999 | } |
1000 | } | |
28a6d671 | 1001 | rcu_read_unlock(); |
d6e71144 | 1002 | return 0; |
1da177e4 LT |
1003 | } |
1004 | ||
1da177e4 LT |
1005 | /* dentry stuff */ |
1006 | ||
1007 | /* | |
1008 | * Exceptional case: normally we are not allowed to unhash a busy | |
1009 | * directory. In this case, however, we can do it - no aliasing problems | |
1010 | * due to the way we treat inodes. | |
1011 | * | |
1012 | * Rewrite the inode's ownerships here because the owning task may have | |
1013 | * performed a setuid(), etc. | |
99f89551 EB |
1014 | * |
1015 | * Before the /proc/pid/status file was created the only way to read | |
1016 | * the effective uid of a /process was to stat /proc/pid. Reading | |
1017 | * /proc/pid/status is slow enough that procps and other packages | |
1018 | * kept stating /proc/pid. To keep the rules in /proc simple I have | |
1019 | * made this apply to all per process world readable and executable | |
1020 | * directories. | |
1da177e4 LT |
1021 | */ |
1022 | static int pid_revalidate(struct dentry *dentry, struct nameidata *nd) | |
1023 | { | |
1024 | struct inode *inode = dentry->d_inode; | |
99f89551 EB |
1025 | struct task_struct *task = get_proc_task(inode); |
1026 | if (task) { | |
1027 | if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || | |
1028 | task_dumpable(task)) { | |
1da177e4 LT |
1029 | inode->i_uid = task->euid; |
1030 | inode->i_gid = task->egid; | |
1031 | } else { | |
1032 | inode->i_uid = 0; | |
1033 | inode->i_gid = 0; | |
1034 | } | |
9ee8ab9f | 1035 | inode->i_mode &= ~(S_ISUID | S_ISGID); |
1da177e4 | 1036 | security_task_to_inode(task, inode); |
99f89551 | 1037 | put_task_struct(task); |
1da177e4 LT |
1038 | return 1; |
1039 | } | |
1040 | d_drop(dentry); | |
1041 | return 0; | |
1042 | } | |
1043 | ||
28a6d671 | 1044 | static int pid_delete_dentry(struct dentry * dentry) |
99f89551 | 1045 | { |
28a6d671 EB |
1046 | /* Is the task we represent dead? |
1047 | * If so, then don't put the dentry on the lru list, | |
1048 | * kill it immediately. | |
1049 | */ | |
1050 | return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first; | |
1051 | } | |
1052 | ||
1053 | static struct dentry_operations pid_dentry_operations = | |
1054 | { | |
1055 | .d_revalidate = pid_revalidate, | |
1056 | .d_delete = pid_delete_dentry, | |
1057 | }; | |
1058 | ||
1059 | /* Lookups */ | |
1060 | ||
61a28784 EB |
1061 | typedef struct dentry *instantiate_t(struct inode *, struct dentry *, struct task_struct *, void *); |
1062 | ||
1c0d04c9 EB |
1063 | /* |
1064 | * Fill a directory entry. | |
1065 | * | |
1066 | * If possible create the dcache entry and derive our inode number and | |
1067 | * file type from dcache entry. | |
1068 | * | |
1069 | * Since all of the proc inode numbers are dynamically generated, the inode | |
1070 | * numbers do not exist until the inode is cache. This means creating the | |
1071 | * the dcache entry in readdir is necessary to keep the inode numbers | |
1072 | * reported by readdir in sync with the inode numbers reported | |
1073 | * by stat. | |
1074 | */ | |
61a28784 EB |
1075 | static int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir, |
1076 | char *name, int len, | |
1077 | instantiate_t instantiate, struct task_struct *task, void *ptr) | |
1078 | { | |
1079 | struct dentry *child, *dir = filp->f_dentry; | |
1080 | struct inode *inode; | |
1081 | struct qstr qname; | |
1082 | ino_t ino = 0; | |
1083 | unsigned type = DT_UNKNOWN; | |
1084 | ||
1085 | qname.name = name; | |
1086 | qname.len = len; | |
1087 | qname.hash = full_name_hash(name, len); | |
1088 | ||
1089 | child = d_lookup(dir, &qname); | |
1090 | if (!child) { | |
1091 | struct dentry *new; | |
1092 | new = d_alloc(dir, &qname); | |
1093 | if (new) { | |
1094 | child = instantiate(dir->d_inode, new, task, ptr); | |
1095 | if (child) | |
1096 | dput(new); | |
1097 | else | |
1098 | child = new; | |
1099 | } | |
1100 | } | |
1101 | if (!child || IS_ERR(child) || !child->d_inode) | |
1102 | goto end_instantiate; | |
1103 | inode = child->d_inode; | |
1104 | if (inode) { | |
1105 | ino = inode->i_ino; | |
1106 | type = inode->i_mode >> 12; | |
1107 | } | |
1108 | dput(child); | |
1109 | end_instantiate: | |
1110 | if (!ino) | |
1111 | ino = find_inode_number(dir, &qname); | |
1112 | if (!ino) | |
1113 | ino = 1; | |
1114 | return filldir(dirent, name, len, filp->f_pos, ino, type); | |
1115 | } | |
1116 | ||
28a6d671 EB |
1117 | static unsigned name_to_int(struct dentry *dentry) |
1118 | { | |
1119 | const char *name = dentry->d_name.name; | |
1120 | int len = dentry->d_name.len; | |
1121 | unsigned n = 0; | |
1122 | ||
1123 | if (len > 1 && *name == '0') | |
1124 | goto out; | |
1125 | while (len-- > 0) { | |
1126 | unsigned c = *name++ - '0'; | |
1127 | if (c > 9) | |
1128 | goto out; | |
1129 | if (n >= (~0U-9)/10) | |
1130 | goto out; | |
1131 | n *= 10; | |
1132 | n += c; | |
1133 | } | |
1134 | return n; | |
1135 | out: | |
1136 | return ~0U; | |
1137 | } | |
1138 | ||
1139 | static int proc_fd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt) | |
1140 | { | |
1141 | struct task_struct *task = get_proc_task(inode); | |
1142 | struct files_struct *files = NULL; | |
1143 | struct file *file; | |
1144 | int fd = proc_fd(inode); | |
99f89551 | 1145 | |
99f89551 | 1146 | if (task) { |
28a6d671 EB |
1147 | files = get_files_struct(task); |
1148 | put_task_struct(task); | |
1149 | } | |
1150 | if (files) { | |
1151 | /* | |
1152 | * We are not taking a ref to the file structure, so we must | |
1153 | * hold ->file_lock. | |
1154 | */ | |
1155 | spin_lock(&files->file_lock); | |
1156 | file = fcheck_files(files, fd); | |
1157 | if (file) { | |
1158 | *mnt = mntget(file->f_vfsmnt); | |
1159 | *dentry = dget(file->f_dentry); | |
1160 | spin_unlock(&files->file_lock); | |
1161 | put_files_struct(files); | |
1162 | return 0; | |
99f89551 | 1163 | } |
28a6d671 EB |
1164 | spin_unlock(&files->file_lock); |
1165 | put_files_struct(files); | |
99f89551 | 1166 | } |
28a6d671 | 1167 | return -ENOENT; |
99f89551 EB |
1168 | } |
1169 | ||
1da177e4 LT |
1170 | static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd) |
1171 | { | |
1172 | struct inode *inode = dentry->d_inode; | |
99f89551 | 1173 | struct task_struct *task = get_proc_task(inode); |
aed7a6c4 | 1174 | int fd = proc_fd(inode); |
1da177e4 LT |
1175 | struct files_struct *files; |
1176 | ||
99f89551 EB |
1177 | if (task) { |
1178 | files = get_files_struct(task); | |
1179 | if (files) { | |
1180 | rcu_read_lock(); | |
1181 | if (fcheck_files(files, fd)) { | |
1182 | rcu_read_unlock(); | |
1183 | put_files_struct(files); | |
1184 | if (task_dumpable(task)) { | |
1185 | inode->i_uid = task->euid; | |
1186 | inode->i_gid = task->egid; | |
1187 | } else { | |
1188 | inode->i_uid = 0; | |
1189 | inode->i_gid = 0; | |
1190 | } | |
9ee8ab9f | 1191 | inode->i_mode &= ~(S_ISUID | S_ISGID); |
99f89551 EB |
1192 | security_task_to_inode(task, inode); |
1193 | put_task_struct(task); | |
1194 | return 1; | |
1195 | } | |
b835996f | 1196 | rcu_read_unlock(); |
1da177e4 | 1197 | put_files_struct(files); |
1da177e4 | 1198 | } |
99f89551 | 1199 | put_task_struct(task); |
1da177e4 LT |
1200 | } |
1201 | d_drop(dentry); | |
1202 | return 0; | |
1203 | } | |
1204 | ||
1da177e4 LT |
1205 | static struct dentry_operations tid_fd_dentry_operations = |
1206 | { | |
1207 | .d_revalidate = tid_fd_revalidate, | |
1208 | .d_delete = pid_delete_dentry, | |
1209 | }; | |
1210 | ||
444ceed8 EB |
1211 | static struct dentry *proc_fd_instantiate(struct inode *dir, |
1212 | struct dentry *dentry, struct task_struct *task, void *ptr) | |
1da177e4 | 1213 | { |
444ceed8 EB |
1214 | unsigned fd = *(unsigned *)ptr; |
1215 | struct file *file; | |
1216 | struct files_struct *files; | |
1217 | struct inode *inode; | |
1218 | struct proc_inode *ei; | |
1219 | struct dentry *error = ERR_PTR(-ENOENT); | |
1da177e4 | 1220 | |
61a28784 | 1221 | inode = proc_pid_make_inode(dir->i_sb, task); |
1da177e4 LT |
1222 | if (!inode) |
1223 | goto out; | |
1224 | ei = PROC_I(inode); | |
aed7a6c4 | 1225 | ei->fd = fd; |
1da177e4 LT |
1226 | files = get_files_struct(task); |
1227 | if (!files) | |
444ceed8 | 1228 | goto out_iput; |
1da177e4 | 1229 | inode->i_mode = S_IFLNK; |
ca99c1da DS |
1230 | |
1231 | /* | |
1232 | * We are not taking a ref to the file structure, so we must | |
1233 | * hold ->file_lock. | |
1234 | */ | |
1235 | spin_lock(&files->file_lock); | |
1da177e4 LT |
1236 | file = fcheck_files(files, fd); |
1237 | if (!file) | |
444ceed8 | 1238 | goto out_unlock; |
1da177e4 LT |
1239 | if (file->f_mode & 1) |
1240 | inode->i_mode |= S_IRUSR | S_IXUSR; | |
1241 | if (file->f_mode & 2) | |
1242 | inode->i_mode |= S_IWUSR | S_IXUSR; | |
ca99c1da | 1243 | spin_unlock(&files->file_lock); |
1da177e4 | 1244 | put_files_struct(files); |
444ceed8 | 1245 | |
1da177e4 LT |
1246 | inode->i_op = &proc_pid_link_inode_operations; |
1247 | inode->i_size = 64; | |
1248 | ei->op.proc_get_link = proc_fd_link; | |
1249 | dentry->d_op = &tid_fd_dentry_operations; | |
1250 | d_add(dentry, inode); | |
cd6a3ce9 EB |
1251 | /* Close the race of the process dying before we return the dentry */ |
1252 | if (tid_fd_revalidate(dentry, NULL)) | |
444ceed8 | 1253 | error = NULL; |
1da177e4 | 1254 | |
444ceed8 EB |
1255 | out: |
1256 | return error; | |
1257 | out_unlock: | |
ca99c1da | 1258 | spin_unlock(&files->file_lock); |
1da177e4 | 1259 | put_files_struct(files); |
444ceed8 | 1260 | out_iput: |
1da177e4 | 1261 | iput(inode); |
cd6a3ce9 | 1262 | goto out; |
1da177e4 LT |
1263 | } |
1264 | ||
444ceed8 EB |
1265 | static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry, struct nameidata *nd) |
1266 | { | |
1267 | struct task_struct *task = get_proc_task(dir); | |
1268 | unsigned fd = name_to_int(dentry); | |
1269 | struct dentry *result = ERR_PTR(-ENOENT); | |
1270 | ||
1271 | if (!task) | |
1272 | goto out_no_task; | |
1273 | if (fd == ~0U) | |
1274 | goto out; | |
1275 | ||
1276 | result = proc_fd_instantiate(dir, dentry, task, &fd); | |
1277 | out: | |
1278 | put_task_struct(task); | |
1279 | out_no_task: | |
1280 | return result; | |
1281 | } | |
1282 | ||
61a28784 EB |
1283 | static int proc_fd_fill_cache(struct file *filp, void *dirent, filldir_t filldir, |
1284 | struct task_struct *task, int fd) | |
1285 | { | |
1286 | char name[PROC_NUMBUF]; | |
1287 | int len = snprintf(name, sizeof(name), "%d", fd); | |
1288 | return proc_fill_cache(filp, dirent, filldir, name, len, | |
1289 | proc_fd_instantiate, task, &fd); | |
1290 | } | |
1291 | ||
28a6d671 EB |
1292 | static int proc_readfd(struct file * filp, void * dirent, filldir_t filldir) |
1293 | { | |
1294 | struct dentry *dentry = filp->f_dentry; | |
1295 | struct inode *inode = dentry->d_inode; | |
1296 | struct task_struct *p = get_proc_task(inode); | |
1297 | unsigned int fd, tid, ino; | |
1298 | int retval; | |
28a6d671 EB |
1299 | struct files_struct * files; |
1300 | struct fdtable *fdt; | |
1da177e4 | 1301 | |
28a6d671 EB |
1302 | retval = -ENOENT; |
1303 | if (!p) | |
1304 | goto out_no_task; | |
1305 | retval = 0; | |
1306 | tid = p->pid; | |
1307 | ||
1308 | fd = filp->f_pos; | |
1309 | switch (fd) { | |
1310 | case 0: | |
1311 | if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0) | |
1312 | goto out; | |
1313 | filp->f_pos++; | |
1314 | case 1: | |
1315 | ino = parent_ino(dentry); | |
1316 | if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0) | |
1317 | goto out; | |
1318 | filp->f_pos++; | |
1319 | default: | |
1320 | files = get_files_struct(p); | |
1321 | if (!files) | |
1322 | goto out; | |
1323 | rcu_read_lock(); | |
1324 | fdt = files_fdtable(files); | |
1325 | for (fd = filp->f_pos-2; | |
1326 | fd < fdt->max_fds; | |
1327 | fd++, filp->f_pos++) { | |
28a6d671 EB |
1328 | |
1329 | if (!fcheck_files(files, fd)) | |
1330 | continue; | |
1331 | rcu_read_unlock(); | |
1332 | ||
61a28784 | 1333 | if (proc_fd_fill_cache(filp, dirent, filldir, p, fd) < 0) { |
28a6d671 EB |
1334 | rcu_read_lock(); |
1335 | break; | |
1336 | } | |
1337 | rcu_read_lock(); | |
1338 | } | |
1339 | rcu_read_unlock(); | |
1340 | put_files_struct(files); | |
1341 | } | |
1342 | out: | |
1343 | put_task_struct(p); | |
1344 | out_no_task: | |
1345 | return retval; | |
1346 | } | |
1347 | ||
1348 | static struct file_operations proc_fd_operations = { | |
1349 | .read = generic_read_dir, | |
1350 | .readdir = proc_readfd, | |
1da177e4 LT |
1351 | }; |
1352 | ||
1353 | /* | |
1354 | * proc directories can do almost nothing.. | |
1355 | */ | |
1356 | static struct inode_operations proc_fd_inode_operations = { | |
1357 | .lookup = proc_lookupfd, | |
6d76fa58 | 1358 | .setattr = proc_setattr, |
1da177e4 LT |
1359 | }; |
1360 | ||
444ceed8 EB |
1361 | static struct dentry *proc_pident_instantiate(struct inode *dir, |
1362 | struct dentry *dentry, struct task_struct *task, void *ptr) | |
1363 | { | |
1364 | struct pid_entry *p = ptr; | |
1365 | struct inode *inode; | |
1366 | struct proc_inode *ei; | |
1367 | struct dentry *error = ERR_PTR(-EINVAL); | |
1368 | ||
61a28784 | 1369 | inode = proc_pid_make_inode(dir->i_sb, task); |
444ceed8 EB |
1370 | if (!inode) |
1371 | goto out; | |
1372 | ||
1373 | ei = PROC_I(inode); | |
1374 | inode->i_mode = p->mode; | |
1375 | if (S_ISDIR(inode->i_mode)) | |
1376 | inode->i_nlink = 2; /* Use getattr to fix if necessary */ | |
1377 | if (p->iop) | |
1378 | inode->i_op = p->iop; | |
1379 | if (p->fop) | |
1380 | inode->i_fop = p->fop; | |
1381 | ei->op = p->op; | |
1382 | dentry->d_op = &pid_dentry_operations; | |
1383 | d_add(dentry, inode); | |
1384 | /* Close the race of the process dying before we return the dentry */ | |
1385 | if (pid_revalidate(dentry, NULL)) | |
1386 | error = NULL; | |
1387 | out: | |
1388 | return error; | |
1389 | } | |
1390 | ||
1da177e4 LT |
1391 | static struct dentry *proc_pident_lookup(struct inode *dir, |
1392 | struct dentry *dentry, | |
7bcd6b0e EB |
1393 | struct pid_entry *ents, |
1394 | unsigned int nents) | |
1da177e4 LT |
1395 | { |
1396 | struct inode *inode; | |
cd6a3ce9 | 1397 | struct dentry *error; |
99f89551 | 1398 | struct task_struct *task = get_proc_task(dir); |
7bcd6b0e | 1399 | struct pid_entry *p, *last; |
1da177e4 | 1400 | |
cd6a3ce9 | 1401 | error = ERR_PTR(-ENOENT); |
1da177e4 LT |
1402 | inode = NULL; |
1403 | ||
99f89551 EB |
1404 | if (!task) |
1405 | goto out_no_task; | |
1da177e4 | 1406 | |
20cdc894 EB |
1407 | /* |
1408 | * Yes, it does not scale. And it should not. Don't add | |
1409 | * new entries into /proc/<tgid>/ without very good reasons. | |
1410 | */ | |
7bcd6b0e EB |
1411 | last = &ents[nents - 1]; |
1412 | for (p = ents; p <= last; p++) { | |
1da177e4 LT |
1413 | if (p->len != dentry->d_name.len) |
1414 | continue; | |
1415 | if (!memcmp(dentry->d_name.name, p->name, p->len)) | |
1416 | break; | |
1417 | } | |
7bcd6b0e | 1418 | if (p > last) |
1da177e4 LT |
1419 | goto out; |
1420 | ||
444ceed8 | 1421 | error = proc_pident_instantiate(dir, dentry, task, p); |
1da177e4 | 1422 | out: |
99f89551 EB |
1423 | put_task_struct(task); |
1424 | out_no_task: | |
cd6a3ce9 | 1425 | return error; |
1da177e4 LT |
1426 | } |
1427 | ||
61a28784 EB |
1428 | static int proc_pident_fill_cache(struct file *filp, void *dirent, filldir_t filldir, |
1429 | struct task_struct *task, struct pid_entry *p) | |
1430 | { | |
1431 | return proc_fill_cache(filp, dirent, filldir, p->name, p->len, | |
1432 | proc_pident_instantiate, task, p); | |
1433 | } | |
1434 | ||
28a6d671 EB |
1435 | static int proc_pident_readdir(struct file *filp, |
1436 | void *dirent, filldir_t filldir, | |
1437 | struct pid_entry *ents, unsigned int nents) | |
1438 | { | |
1439 | int i; | |
1440 | int pid; | |
1441 | struct dentry *dentry = filp->f_dentry; | |
1442 | struct inode *inode = dentry->d_inode; | |
1443 | struct task_struct *task = get_proc_task(inode); | |
7bcd6b0e | 1444 | struct pid_entry *p, *last; |
28a6d671 EB |
1445 | ino_t ino; |
1446 | int ret; | |
1447 | ||
1448 | ret = -ENOENT; | |
1449 | if (!task) | |
61a28784 | 1450 | goto out_no_task; |
28a6d671 EB |
1451 | |
1452 | ret = 0; | |
1453 | pid = task->pid; | |
28a6d671 EB |
1454 | i = filp->f_pos; |
1455 | switch (i) { | |
1456 | case 0: | |
1457 | ino = inode->i_ino; | |
1458 | if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) | |
1459 | goto out; | |
1460 | i++; | |
1461 | filp->f_pos++; | |
1462 | /* fall through */ | |
1463 | case 1: | |
1464 | ino = parent_ino(dentry); | |
1465 | if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0) | |
1466 | goto out; | |
1467 | i++; | |
1468 | filp->f_pos++; | |
1469 | /* fall through */ | |
1470 | default: | |
1471 | i -= 2; | |
1472 | if (i >= nents) { | |
1473 | ret = 1; | |
1474 | goto out; | |
1475 | } | |
1476 | p = ents + i; | |
7bcd6b0e EB |
1477 | last = &ents[nents - 1]; |
1478 | while (p <= last) { | |
61a28784 | 1479 | if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0) |
28a6d671 EB |
1480 | goto out; |
1481 | filp->f_pos++; | |
1482 | p++; | |
1483 | } | |
1484 | } | |
1485 | ||
1486 | ret = 1; | |
1487 | out: | |
61a28784 EB |
1488 | put_task_struct(task); |
1489 | out_no_task: | |
28a6d671 | 1490 | return ret; |
1da177e4 LT |
1491 | } |
1492 | ||
28a6d671 EB |
1493 | #ifdef CONFIG_SECURITY |
1494 | static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, | |
1495 | size_t count, loff_t *ppos) | |
1496 | { | |
1497 | struct inode * inode = file->f_dentry->d_inode; | |
1498 | unsigned long page; | |
1499 | ssize_t length; | |
1500 | struct task_struct *task = get_proc_task(inode); | |
1501 | ||
1502 | length = -ESRCH; | |
1503 | if (!task) | |
1504 | goto out_no_task; | |
1505 | ||
1506 | if (count > PAGE_SIZE) | |
1507 | count = PAGE_SIZE; | |
1508 | length = -ENOMEM; | |
1509 | if (!(page = __get_free_page(GFP_KERNEL))) | |
1510 | goto out; | |
1511 | ||
1512 | length = security_getprocattr(task, | |
1513 | (char*)file->f_dentry->d_name.name, | |
1514 | (void*)page, count); | |
1515 | if (length >= 0) | |
1516 | length = simple_read_from_buffer(buf, count, ppos, (char *)page, length); | |
1517 | free_page(page); | |
1518 | out: | |
1519 | put_task_struct(task); | |
1520 | out_no_task: | |
1521 | return length; | |
1da177e4 LT |
1522 | } |
1523 | ||
28a6d671 EB |
1524 | static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, |
1525 | size_t count, loff_t *ppos) | |
1526 | { | |
1527 | struct inode * inode = file->f_dentry->d_inode; | |
1528 | char *page; | |
1529 | ssize_t length; | |
1530 | struct task_struct *task = get_proc_task(inode); | |
1531 | ||
1532 | length = -ESRCH; | |
1533 | if (!task) | |
1534 | goto out_no_task; | |
1535 | if (count > PAGE_SIZE) | |
1536 | count = PAGE_SIZE; | |
1537 | ||
1538 | /* No partial writes. */ | |
1539 | length = -EINVAL; | |
1540 | if (*ppos != 0) | |
1541 | goto out; | |
1542 | ||
1543 | length = -ENOMEM; | |
1544 | page = (char*)__get_free_page(GFP_USER); | |
1545 | if (!page) | |
1546 | goto out; | |
1547 | ||
1548 | length = -EFAULT; | |
1549 | if (copy_from_user(page, buf, count)) | |
1550 | goto out_free; | |
1551 | ||
1552 | length = security_setprocattr(task, | |
1553 | (char*)file->f_dentry->d_name.name, | |
1554 | (void*)page, count); | |
1555 | out_free: | |
1556 | free_page((unsigned long) page); | |
1557 | out: | |
1558 | put_task_struct(task); | |
1559 | out_no_task: | |
1560 | return length; | |
1561 | } | |
1562 | ||
1563 | static struct file_operations proc_pid_attr_operations = { | |
1564 | .read = proc_pid_attr_read, | |
1565 | .write = proc_pid_attr_write, | |
1566 | }; | |
1567 | ||
72d9dcfc | 1568 | static struct pid_entry attr_dir_stuff[] = { |
61a28784 EB |
1569 | REG("current", S_IRUGO|S_IWUGO, pid_attr), |
1570 | REG("prev", S_IRUGO, pid_attr), | |
1571 | REG("exec", S_IRUGO|S_IWUGO, pid_attr), | |
1572 | REG("fscreate", S_IRUGO|S_IWUGO, pid_attr), | |
1573 | REG("keycreate", S_IRUGO|S_IWUGO, pid_attr), | |
1574 | REG("sockcreate", S_IRUGO|S_IWUGO, pid_attr), | |
28a6d671 EB |
1575 | }; |
1576 | ||
72d9dcfc | 1577 | static int proc_attr_dir_readdir(struct file * filp, |
28a6d671 EB |
1578 | void * dirent, filldir_t filldir) |
1579 | { | |
1580 | return proc_pident_readdir(filp,dirent,filldir, | |
72d9dcfc | 1581 | attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff)); |
28a6d671 EB |
1582 | } |
1583 | ||
72d9dcfc | 1584 | static struct file_operations proc_attr_dir_operations = { |
1da177e4 | 1585 | .read = generic_read_dir, |
72d9dcfc | 1586 | .readdir = proc_attr_dir_readdir, |
1da177e4 LT |
1587 | }; |
1588 | ||
72d9dcfc | 1589 | static struct dentry *proc_attr_dir_lookup(struct inode *dir, |
28a6d671 EB |
1590 | struct dentry *dentry, struct nameidata *nd) |
1591 | { | |
7bcd6b0e EB |
1592 | return proc_pident_lookup(dir, dentry, |
1593 | attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); | |
28a6d671 EB |
1594 | } |
1595 | ||
72d9dcfc EB |
1596 | static struct inode_operations proc_attr_dir_inode_operations = { |
1597 | .lookup = proc_attr_dir_lookup, | |
99f89551 | 1598 | .getattr = pid_getattr, |
6d76fa58 | 1599 | .setattr = proc_setattr, |
1da177e4 LT |
1600 | }; |
1601 | ||
28a6d671 EB |
1602 | #endif |
1603 | ||
1604 | /* | |
1605 | * /proc/self: | |
1606 | */ | |
1607 | static int proc_self_readlink(struct dentry *dentry, char __user *buffer, | |
1608 | int buflen) | |
1609 | { | |
1610 | char tmp[PROC_NUMBUF]; | |
1611 | sprintf(tmp, "%d", current->tgid); | |
1612 | return vfs_readlink(dentry,buffer,buflen,tmp); | |
1613 | } | |
1614 | ||
1615 | static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd) | |
1616 | { | |
1617 | char tmp[PROC_NUMBUF]; | |
1618 | sprintf(tmp, "%d", current->tgid); | |
1619 | return ERR_PTR(vfs_follow_link(nd,tmp)); | |
1620 | } | |
1621 | ||
1622 | static struct inode_operations proc_self_inode_operations = { | |
1623 | .readlink = proc_self_readlink, | |
1624 | .follow_link = proc_self_follow_link, | |
1625 | }; | |
1626 | ||
801199ce EB |
1627 | /* |
1628 | * proc base | |
1629 | * | |
1630 | * These are the directory entries in the root directory of /proc | |
1631 | * that properly belong to the /proc filesystem, as they describe | |
1632 | * describe something that is process related. | |
1633 | */ | |
1634 | static struct pid_entry proc_base_stuff[] = { | |
61a28784 | 1635 | NOD("self", S_IFLNK|S_IRWXUGO, |
801199ce | 1636 | &proc_self_inode_operations, NULL, {}), |
801199ce EB |
1637 | }; |
1638 | ||
1639 | /* | |
1640 | * Exceptional case: normally we are not allowed to unhash a busy | |
1641 | * directory. In this case, however, we can do it - no aliasing problems | |
1642 | * due to the way we treat inodes. | |
1643 | */ | |
1644 | static int proc_base_revalidate(struct dentry *dentry, struct nameidata *nd) | |
1645 | { | |
1646 | struct inode *inode = dentry->d_inode; | |
1647 | struct task_struct *task = get_proc_task(inode); | |
1648 | if (task) { | |
1649 | put_task_struct(task); | |
1650 | return 1; | |
1651 | } | |
1652 | d_drop(dentry); | |
1653 | return 0; | |
1654 | } | |
1655 | ||
1656 | static struct dentry_operations proc_base_dentry_operations = | |
1657 | { | |
1658 | .d_revalidate = proc_base_revalidate, | |
1659 | .d_delete = pid_delete_dentry, | |
1660 | }; | |
1661 | ||
444ceed8 EB |
1662 | static struct dentry *proc_base_instantiate(struct inode *dir, |
1663 | struct dentry *dentry, struct task_struct *task, void *ptr) | |
801199ce | 1664 | { |
444ceed8 | 1665 | struct pid_entry *p = ptr; |
801199ce | 1666 | struct inode *inode; |
801199ce | 1667 | struct proc_inode *ei; |
444ceed8 | 1668 | struct dentry *error = ERR_PTR(-EINVAL); |
801199ce EB |
1669 | |
1670 | /* Allocate the inode */ | |
1671 | error = ERR_PTR(-ENOMEM); | |
1672 | inode = new_inode(dir->i_sb); | |
1673 | if (!inode) | |
1674 | goto out; | |
1675 | ||
1676 | /* Initialize the inode */ | |
1677 | ei = PROC_I(inode); | |
1678 | inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; | |
801199ce EB |
1679 | |
1680 | /* | |
1681 | * grab the reference to the task. | |
1682 | */ | |
1a657f78 | 1683 | ei->pid = get_task_pid(task, PIDTYPE_PID); |
801199ce EB |
1684 | if (!ei->pid) |
1685 | goto out_iput; | |
1686 | ||
1687 | inode->i_uid = 0; | |
1688 | inode->i_gid = 0; | |
1689 | inode->i_mode = p->mode; | |
1690 | if (S_ISDIR(inode->i_mode)) | |
1691 | inode->i_nlink = 2; | |
1692 | if (S_ISLNK(inode->i_mode)) | |
1693 | inode->i_size = 64; | |
1694 | if (p->iop) | |
1695 | inode->i_op = p->iop; | |
1696 | if (p->fop) | |
1697 | inode->i_fop = p->fop; | |
1698 | ei->op = p->op; | |
1699 | dentry->d_op = &proc_base_dentry_operations; | |
1700 | d_add(dentry, inode); | |
1701 | error = NULL; | |
1702 | out: | |
801199ce EB |
1703 | return error; |
1704 | out_iput: | |
1705 | iput(inode); | |
1706 | goto out; | |
1707 | } | |
1708 | ||
444ceed8 EB |
1709 | static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry) |
1710 | { | |
1711 | struct dentry *error; | |
1712 | struct task_struct *task = get_proc_task(dir); | |
7bcd6b0e | 1713 | struct pid_entry *p, *last; |
444ceed8 EB |
1714 | |
1715 | error = ERR_PTR(-ENOENT); | |
1716 | ||
1717 | if (!task) | |
1718 | goto out_no_task; | |
1719 | ||
1720 | /* Lookup the directory entry */ | |
7bcd6b0e EB |
1721 | last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1]; |
1722 | for (p = proc_base_stuff; p <= last; p++) { | |
444ceed8 EB |
1723 | if (p->len != dentry->d_name.len) |
1724 | continue; | |
1725 | if (!memcmp(dentry->d_name.name, p->name, p->len)) | |
1726 | break; | |
1727 | } | |
7bcd6b0e | 1728 | if (p > last) |
444ceed8 EB |
1729 | goto out; |
1730 | ||
1731 | error = proc_base_instantiate(dir, dentry, task, p); | |
1732 | ||
1733 | out: | |
1734 | put_task_struct(task); | |
1735 | out_no_task: | |
1736 | return error; | |
1737 | } | |
1738 | ||
61a28784 EB |
1739 | static int proc_base_fill_cache(struct file *filp, void *dirent, filldir_t filldir, |
1740 | struct task_struct *task, struct pid_entry *p) | |
1741 | { | |
1742 | return proc_fill_cache(filp, dirent, filldir, p->name, p->len, | |
1743 | proc_base_instantiate, task, p); | |
1744 | } | |
1745 | ||
28a6d671 EB |
1746 | /* |
1747 | * Thread groups | |
1748 | */ | |
20cdc894 EB |
1749 | static struct file_operations proc_task_operations; |
1750 | static struct inode_operations proc_task_inode_operations; | |
1751 | ||
28a6d671 | 1752 | static struct pid_entry tgid_base_stuff[] = { |
61a28784 EB |
1753 | DIR("task", S_IRUGO|S_IXUGO, task), |
1754 | DIR("fd", S_IRUSR|S_IXUSR, fd), | |
1755 | INF("environ", S_IRUSR, pid_environ), | |
1756 | INF("auxv", S_IRUSR, pid_auxv), | |
1757 | INF("status", S_IRUGO, pid_status), | |
1758 | INF("cmdline", S_IRUGO, pid_cmdline), | |
1759 | INF("stat", S_IRUGO, tgid_stat), | |
1760 | INF("statm", S_IRUGO, pid_statm), | |
1761 | REG("maps", S_IRUGO, maps), | |
28a6d671 | 1762 | #ifdef CONFIG_NUMA |
61a28784 | 1763 | REG("numa_maps", S_IRUGO, numa_maps), |
28a6d671 | 1764 | #endif |
61a28784 | 1765 | REG("mem", S_IRUSR|S_IWUSR, mem), |
28a6d671 | 1766 | #ifdef CONFIG_SECCOMP |
61a28784 | 1767 | REG("seccomp", S_IRUSR|S_IWUSR, seccomp), |
28a6d671 | 1768 | #endif |
61a28784 EB |
1769 | LNK("cwd", cwd), |
1770 | LNK("root", root), | |
1771 | LNK("exe", exe), | |
1772 | REG("mounts", S_IRUGO, mounts), | |
1773 | REG("mountstats", S_IRUSR, mountstats), | |
28a6d671 | 1774 | #ifdef CONFIG_MMU |
61a28784 | 1775 | REG("smaps", S_IRUGO, smaps), |
28a6d671 EB |
1776 | #endif |
1777 | #ifdef CONFIG_SECURITY | |
72d9dcfc | 1778 | DIR("attr", S_IRUGO|S_IXUGO, attr_dir), |
28a6d671 EB |
1779 | #endif |
1780 | #ifdef CONFIG_KALLSYMS | |
61a28784 | 1781 | INF("wchan", S_IRUGO, pid_wchan), |
28a6d671 EB |
1782 | #endif |
1783 | #ifdef CONFIG_SCHEDSTATS | |
61a28784 | 1784 | INF("schedstat", S_IRUGO, pid_schedstat), |
28a6d671 EB |
1785 | #endif |
1786 | #ifdef CONFIG_CPUSETS | |
61a28784 | 1787 | REG("cpuset", S_IRUGO, cpuset), |
28a6d671 | 1788 | #endif |
61a28784 EB |
1789 | INF("oom_score", S_IRUGO, oom_score), |
1790 | REG("oom_adj", S_IRUGO|S_IWUSR, oom_adjust), | |
28a6d671 | 1791 | #ifdef CONFIG_AUDITSYSCALL |
61a28784 | 1792 | REG("loginuid", S_IWUSR|S_IRUGO, loginuid), |
28a6d671 | 1793 | #endif |
28a6d671 | 1794 | }; |
1da177e4 | 1795 | |
28a6d671 | 1796 | static int proc_tgid_base_readdir(struct file * filp, |
1da177e4 LT |
1797 | void * dirent, filldir_t filldir) |
1798 | { | |
1799 | return proc_pident_readdir(filp,dirent,filldir, | |
28a6d671 | 1800 | tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff)); |
1da177e4 LT |
1801 | } |
1802 | ||
28a6d671 | 1803 | static struct file_operations proc_tgid_base_operations = { |
1da177e4 | 1804 | .read = generic_read_dir, |
28a6d671 | 1805 | .readdir = proc_tgid_base_readdir, |
1da177e4 LT |
1806 | }; |
1807 | ||
28a6d671 | 1808 | static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ |
7bcd6b0e EB |
1809 | return proc_pident_lookup(dir, dentry, |
1810 | tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); | |
1da177e4 LT |
1811 | } |
1812 | ||
28a6d671 EB |
1813 | static struct inode_operations proc_tgid_base_inode_operations = { |
1814 | .lookup = proc_tgid_base_lookup, | |
99f89551 | 1815 | .getattr = pid_getattr, |
6d76fa58 | 1816 | .setattr = proc_setattr, |
1da177e4 | 1817 | }; |
1da177e4 LT |
1818 | |
1819 | /** | |
48e6484d EB |
1820 | * proc_flush_task - Remove dcache entries for @task from the /proc dcache. |
1821 | * | |
1822 | * @task: task that should be flushed. | |
1823 | * | |
1824 | * Looks in the dcache for | |
1825 | * /proc/@pid | |
1826 | * /proc/@tgid/task/@pid | |
1827 | * if either directory is present flushes it and all of it'ts children | |
1828 | * from the dcache. | |
1da177e4 | 1829 | * |
48e6484d EB |
1830 | * It is safe and reasonable to cache /proc entries for a task until |
1831 | * that task exits. After that they just clog up the dcache with | |
1832 | * useless entries, possibly causing useful dcache entries to be | |
1833 | * flushed instead. This routine is proved to flush those useless | |
1834 | * dcache entries at process exit time. | |
1da177e4 | 1835 | * |
48e6484d EB |
1836 | * NOTE: This routine is just an optimization so it does not guarantee |
1837 | * that no dcache entries will exist at process exit time it | |
1838 | * just makes it very unlikely that any will persist. | |
1da177e4 | 1839 | */ |
48e6484d | 1840 | void proc_flush_task(struct task_struct *task) |
1da177e4 | 1841 | { |
48e6484d | 1842 | struct dentry *dentry, *leader, *dir; |
8578cea7 | 1843 | char buf[PROC_NUMBUF]; |
48e6484d EB |
1844 | struct qstr name; |
1845 | ||
1846 | name.name = buf; | |
1847 | name.len = snprintf(buf, sizeof(buf), "%d", task->pid); | |
1848 | dentry = d_hash_and_lookup(proc_mnt->mnt_root, &name); | |
1849 | if (dentry) { | |
1850 | shrink_dcache_parent(dentry); | |
1851 | d_drop(dentry); | |
1852 | dput(dentry); | |
1853 | } | |
1da177e4 | 1854 | |
48e6484d EB |
1855 | if (thread_group_leader(task)) |
1856 | goto out; | |
1da177e4 | 1857 | |
48e6484d EB |
1858 | name.name = buf; |
1859 | name.len = snprintf(buf, sizeof(buf), "%d", task->tgid); | |
1860 | leader = d_hash_and_lookup(proc_mnt->mnt_root, &name); | |
1861 | if (!leader) | |
1862 | goto out; | |
1da177e4 | 1863 | |
48e6484d EB |
1864 | name.name = "task"; |
1865 | name.len = strlen(name.name); | |
1866 | dir = d_hash_and_lookup(leader, &name); | |
1867 | if (!dir) | |
1868 | goto out_put_leader; | |
1869 | ||
1870 | name.name = buf; | |
1871 | name.len = snprintf(buf, sizeof(buf), "%d", task->pid); | |
1872 | dentry = d_hash_and_lookup(dir, &name); | |
1873 | if (dentry) { | |
1874 | shrink_dcache_parent(dentry); | |
1875 | d_drop(dentry); | |
1876 | dput(dentry); | |
1da177e4 | 1877 | } |
48e6484d EB |
1878 | |
1879 | dput(dir); | |
1880 | out_put_leader: | |
1881 | dput(leader); | |
1882 | out: | |
1883 | return; | |
1da177e4 LT |
1884 | } |
1885 | ||
444ceed8 EB |
1886 | struct dentry *proc_pid_instantiate(struct inode *dir, |
1887 | struct dentry * dentry, struct task_struct *task, void *ptr) | |
1888 | { | |
1889 | struct dentry *error = ERR_PTR(-ENOENT); | |
1890 | struct inode *inode; | |
1891 | ||
61a28784 | 1892 | inode = proc_pid_make_inode(dir->i_sb, task); |
444ceed8 EB |
1893 | if (!inode) |
1894 | goto out; | |
1895 | ||
1896 | inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; | |
1897 | inode->i_op = &proc_tgid_base_inode_operations; | |
1898 | inode->i_fop = &proc_tgid_base_operations; | |
1899 | inode->i_flags|=S_IMMUTABLE; | |
1900 | inode->i_nlink = 4; | |
1901 | #ifdef CONFIG_SECURITY | |
1902 | inode->i_nlink += 1; | |
1903 | #endif | |
1904 | ||
1905 | dentry->d_op = &pid_dentry_operations; | |
1906 | ||
1907 | d_add(dentry, inode); | |
1908 | /* Close the race of the process dying before we return the dentry */ | |
1909 | if (pid_revalidate(dentry, NULL)) | |
1910 | error = NULL; | |
1911 | out: | |
1912 | return error; | |
1913 | } | |
1914 | ||
1da177e4 LT |
1915 | struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) |
1916 | { | |
cd6a3ce9 | 1917 | struct dentry *result = ERR_PTR(-ENOENT); |
1da177e4 | 1918 | struct task_struct *task; |
1da177e4 | 1919 | unsigned tgid; |
1da177e4 | 1920 | |
801199ce EB |
1921 | result = proc_base_lookup(dir, dentry); |
1922 | if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT) | |
1923 | goto out; | |
1924 | ||
1da177e4 LT |
1925 | tgid = name_to_int(dentry); |
1926 | if (tgid == ~0U) | |
1927 | goto out; | |
1928 | ||
de758734 | 1929 | rcu_read_lock(); |
1da177e4 LT |
1930 | task = find_task_by_pid(tgid); |
1931 | if (task) | |
1932 | get_task_struct(task); | |
de758734 | 1933 | rcu_read_unlock(); |
1da177e4 LT |
1934 | if (!task) |
1935 | goto out; | |
1936 | ||
444ceed8 | 1937 | result = proc_pid_instantiate(dir, dentry, task, NULL); |
1da177e4 | 1938 | put_task_struct(task); |
1da177e4 | 1939 | out: |
cd6a3ce9 | 1940 | return result; |
1da177e4 LT |
1941 | } |
1942 | ||
1da177e4 | 1943 | /* |
0804ef4b | 1944 | * Find the first task with tgid >= tgid |
0bc58a91 | 1945 | * |
1da177e4 | 1946 | */ |
0804ef4b | 1947 | static struct task_struct *next_tgid(unsigned int tgid) |
1da177e4 | 1948 | { |
0804ef4b EB |
1949 | struct task_struct *task; |
1950 | struct pid *pid; | |
1da177e4 | 1951 | |
454cc105 | 1952 | rcu_read_lock(); |
0804ef4b EB |
1953 | retry: |
1954 | task = NULL; | |
1955 | pid = find_ge_pid(tgid); | |
1956 | if (pid) { | |
1957 | tgid = pid->nr + 1; | |
1958 | task = pid_task(pid, PIDTYPE_PID); | |
1959 | /* What we to know is if the pid we have find is the | |
1960 | * pid of a thread_group_leader. Testing for task | |
1961 | * being a thread_group_leader is the obvious thing | |
1962 | * todo but there is a window when it fails, due to | |
1963 | * the pid transfer logic in de_thread. | |
1964 | * | |
1965 | * So we perform the straight forward test of seeing | |
1966 | * if the pid we have found is the pid of a thread | |
1967 | * group leader, and don't worry if the task we have | |
1968 | * found doesn't happen to be a thread group leader. | |
1969 | * As we don't care in the case of readdir. | |
1970 | */ | |
1971 | if (!task || !has_group_leader_pid(task)) | |
1972 | goto retry; | |
1973 | get_task_struct(task); | |
0bc58a91 | 1974 | } |
454cc105 | 1975 | rcu_read_unlock(); |
0804ef4b | 1976 | return task; |
1da177e4 LT |
1977 | } |
1978 | ||
7bcd6b0e | 1979 | #define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff)) |
0804ef4b | 1980 | |
61a28784 EB |
1981 | static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir, |
1982 | struct task_struct *task, int tgid) | |
1983 | { | |
1984 | char name[PROC_NUMBUF]; | |
1985 | int len = snprintf(name, sizeof(name), "%d", tgid); | |
1986 | return proc_fill_cache(filp, dirent, filldir, name, len, | |
1987 | proc_pid_instantiate, task, NULL); | |
1988 | } | |
1989 | ||
1da177e4 LT |
1990 | /* for the /proc/ directory itself, after non-process stuff has been done */ |
1991 | int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir) | |
1992 | { | |
1da177e4 | 1993 | unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY; |
61a28784 | 1994 | struct task_struct *reaper = get_proc_task(filp->f_dentry->d_inode); |
0bc58a91 EB |
1995 | struct task_struct *task; |
1996 | int tgid; | |
1da177e4 | 1997 | |
61a28784 EB |
1998 | if (!reaper) |
1999 | goto out_no_task; | |
2000 | ||
7bcd6b0e | 2001 | for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) { |
801199ce | 2002 | struct pid_entry *p = &proc_base_stuff[nr]; |
61a28784 | 2003 | if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0) |
801199ce | 2004 | goto out; |
1da177e4 LT |
2005 | } |
2006 | ||
0804ef4b EB |
2007 | tgid = filp->f_pos - TGID_OFFSET; |
2008 | for (task = next_tgid(tgid); | |
0bc58a91 | 2009 | task; |
0804ef4b | 2010 | put_task_struct(task), task = next_tgid(tgid + 1)) { |
0bc58a91 | 2011 | tgid = task->pid; |
0804ef4b | 2012 | filp->f_pos = tgid + TGID_OFFSET; |
61a28784 | 2013 | if (proc_pid_fill_cache(filp, dirent, filldir, task, tgid) < 0) { |
0bc58a91 | 2014 | put_task_struct(task); |
0804ef4b | 2015 | goto out; |
1da177e4 | 2016 | } |
0bc58a91 | 2017 | } |
0804ef4b EB |
2018 | filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET; |
2019 | out: | |
61a28784 EB |
2020 | put_task_struct(reaper); |
2021 | out_no_task: | |
0bc58a91 EB |
2022 | return 0; |
2023 | } | |
1da177e4 | 2024 | |
28a6d671 EB |
2025 | /* |
2026 | * Tasks | |
2027 | */ | |
2028 | static struct pid_entry tid_base_stuff[] = { | |
61a28784 EB |
2029 | DIR("fd", S_IRUSR|S_IXUSR, fd), |
2030 | INF("environ", S_IRUSR, pid_environ), | |
2031 | INF("auxv", S_IRUSR, pid_auxv), | |
2032 | INF("status", S_IRUGO, pid_status), | |
2033 | INF("cmdline", S_IRUGO, pid_cmdline), | |
2034 | INF("stat", S_IRUGO, tid_stat), | |
2035 | INF("statm", S_IRUGO, pid_statm), | |
2036 | REG("maps", S_IRUGO, maps), | |
28a6d671 | 2037 | #ifdef CONFIG_NUMA |
61a28784 | 2038 | REG("numa_maps", S_IRUGO, numa_maps), |
28a6d671 | 2039 | #endif |
61a28784 | 2040 | REG("mem", S_IRUSR|S_IWUSR, mem), |
28a6d671 | 2041 | #ifdef CONFIG_SECCOMP |
61a28784 | 2042 | REG("seccomp", S_IRUSR|S_IWUSR, seccomp), |
28a6d671 | 2043 | #endif |
61a28784 EB |
2044 | LNK("cwd", cwd), |
2045 | LNK("root", root), | |
2046 | LNK("exe", exe), | |
2047 | REG("mounts", S_IRUGO, mounts), | |
28a6d671 | 2048 | #ifdef CONFIG_MMU |
61a28784 | 2049 | REG("smaps", S_IRUGO, smaps), |
28a6d671 EB |
2050 | #endif |
2051 | #ifdef CONFIG_SECURITY | |
72d9dcfc | 2052 | DIR("attr", S_IRUGO|S_IXUGO, attr_dir), |
28a6d671 EB |
2053 | #endif |
2054 | #ifdef CONFIG_KALLSYMS | |
61a28784 | 2055 | INF("wchan", S_IRUGO, pid_wchan), |
28a6d671 EB |
2056 | #endif |
2057 | #ifdef CONFIG_SCHEDSTATS | |
61a28784 | 2058 | INF("schedstat", S_IRUGO, pid_schedstat), |
28a6d671 EB |
2059 | #endif |
2060 | #ifdef CONFIG_CPUSETS | |
61a28784 | 2061 | REG("cpuset", S_IRUGO, cpuset), |
28a6d671 | 2062 | #endif |
61a28784 EB |
2063 | INF("oom_score", S_IRUGO, oom_score), |
2064 | REG("oom_adj", S_IRUGO|S_IWUSR, oom_adjust), | |
28a6d671 | 2065 | #ifdef CONFIG_AUDITSYSCALL |
61a28784 | 2066 | REG("loginuid", S_IWUSR|S_IRUGO, loginuid), |
28a6d671 | 2067 | #endif |
28a6d671 EB |
2068 | }; |
2069 | ||
2070 | static int proc_tid_base_readdir(struct file * filp, | |
2071 | void * dirent, filldir_t filldir) | |
2072 | { | |
2073 | return proc_pident_readdir(filp,dirent,filldir, | |
2074 | tid_base_stuff,ARRAY_SIZE(tid_base_stuff)); | |
2075 | } | |
2076 | ||
2077 | static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ | |
7bcd6b0e EB |
2078 | return proc_pident_lookup(dir, dentry, |
2079 | tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); | |
28a6d671 EB |
2080 | } |
2081 | ||
2082 | static struct file_operations proc_tid_base_operations = { | |
2083 | .read = generic_read_dir, | |
2084 | .readdir = proc_tid_base_readdir, | |
2085 | }; | |
2086 | ||
2087 | static struct inode_operations proc_tid_base_inode_operations = { | |
2088 | .lookup = proc_tid_base_lookup, | |
2089 | .getattr = pid_getattr, | |
2090 | .setattr = proc_setattr, | |
2091 | }; | |
2092 | ||
444ceed8 EB |
2093 | static struct dentry *proc_task_instantiate(struct inode *dir, |
2094 | struct dentry *dentry, struct task_struct *task, void *ptr) | |
2095 | { | |
2096 | struct dentry *error = ERR_PTR(-ENOENT); | |
2097 | struct inode *inode; | |
61a28784 | 2098 | inode = proc_pid_make_inode(dir->i_sb, task); |
444ceed8 EB |
2099 | |
2100 | if (!inode) | |
2101 | goto out; | |
2102 | inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; | |
2103 | inode->i_op = &proc_tid_base_inode_operations; | |
2104 | inode->i_fop = &proc_tid_base_operations; | |
2105 | inode->i_flags|=S_IMMUTABLE; | |
2106 | inode->i_nlink = 3; | |
2107 | #ifdef CONFIG_SECURITY | |
2108 | inode->i_nlink += 1; | |
2109 | #endif | |
2110 | ||
2111 | dentry->d_op = &pid_dentry_operations; | |
2112 | ||
2113 | d_add(dentry, inode); | |
2114 | /* Close the race of the process dying before we return the dentry */ | |
2115 | if (pid_revalidate(dentry, NULL)) | |
2116 | error = NULL; | |
2117 | out: | |
2118 | return error; | |
2119 | } | |
2120 | ||
28a6d671 EB |
2121 | static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) |
2122 | { | |
2123 | struct dentry *result = ERR_PTR(-ENOENT); | |
2124 | struct task_struct *task; | |
2125 | struct task_struct *leader = get_proc_task(dir); | |
28a6d671 EB |
2126 | unsigned tid; |
2127 | ||
2128 | if (!leader) | |
2129 | goto out_no_task; | |
2130 | ||
2131 | tid = name_to_int(dentry); | |
2132 | if (tid == ~0U) | |
2133 | goto out; | |
2134 | ||
2135 | rcu_read_lock(); | |
2136 | task = find_task_by_pid(tid); | |
2137 | if (task) | |
2138 | get_task_struct(task); | |
2139 | rcu_read_unlock(); | |
2140 | if (!task) | |
2141 | goto out; | |
2142 | if (leader->tgid != task->tgid) | |
2143 | goto out_drop_task; | |
2144 | ||
444ceed8 | 2145 | result = proc_task_instantiate(dir, dentry, task, NULL); |
28a6d671 EB |
2146 | out_drop_task: |
2147 | put_task_struct(task); | |
2148 | out: | |
2149 | put_task_struct(leader); | |
2150 | out_no_task: | |
2151 | return result; | |
2152 | } | |
2153 | ||
0bc58a91 EB |
2154 | /* |
2155 | * Find the first tid of a thread group to return to user space. | |
2156 | * | |
2157 | * Usually this is just the thread group leader, but if the users | |
2158 | * buffer was too small or there was a seek into the middle of the | |
2159 | * directory we have more work todo. | |
2160 | * | |
2161 | * In the case of a short read we start with find_task_by_pid. | |
2162 | * | |
2163 | * In the case of a seek we start with the leader and walk nr | |
2164 | * threads past it. | |
2165 | */ | |
cc288738 EB |
2166 | static struct task_struct *first_tid(struct task_struct *leader, |
2167 | int tid, int nr) | |
0bc58a91 | 2168 | { |
a872ff0c | 2169 | struct task_struct *pos; |
1da177e4 | 2170 | |
cc288738 | 2171 | rcu_read_lock(); |
0bc58a91 EB |
2172 | /* Attempt to start with the pid of a thread */ |
2173 | if (tid && (nr > 0)) { | |
2174 | pos = find_task_by_pid(tid); | |
a872ff0c ON |
2175 | if (pos && (pos->group_leader == leader)) |
2176 | goto found; | |
0bc58a91 | 2177 | } |
1da177e4 | 2178 | |
0bc58a91 | 2179 | /* If nr exceeds the number of threads there is nothing todo */ |
a872ff0c ON |
2180 | pos = NULL; |
2181 | if (nr && nr >= get_nr_threads(leader)) | |
2182 | goto out; | |
1da177e4 | 2183 | |
a872ff0c ON |
2184 | /* If we haven't found our starting place yet start |
2185 | * with the leader and walk nr threads forward. | |
0bc58a91 | 2186 | */ |
a872ff0c ON |
2187 | for (pos = leader; nr > 0; --nr) { |
2188 | pos = next_thread(pos); | |
2189 | if (pos == leader) { | |
2190 | pos = NULL; | |
2191 | goto out; | |
2192 | } | |
1da177e4 | 2193 | } |
a872ff0c ON |
2194 | found: |
2195 | get_task_struct(pos); | |
2196 | out: | |
cc288738 | 2197 | rcu_read_unlock(); |
0bc58a91 EB |
2198 | return pos; |
2199 | } | |
2200 | ||
2201 | /* | |
2202 | * Find the next thread in the thread list. | |
2203 | * Return NULL if there is an error or no next thread. | |
2204 | * | |
2205 | * The reference to the input task_struct is released. | |
2206 | */ | |
2207 | static struct task_struct *next_tid(struct task_struct *start) | |
2208 | { | |
c1df7fb8 | 2209 | struct task_struct *pos = NULL; |
cc288738 | 2210 | rcu_read_lock(); |
c1df7fb8 | 2211 | if (pid_alive(start)) { |
0bc58a91 | 2212 | pos = next_thread(start); |
c1df7fb8 ON |
2213 | if (thread_group_leader(pos)) |
2214 | pos = NULL; | |
2215 | else | |
2216 | get_task_struct(pos); | |
2217 | } | |
cc288738 | 2218 | rcu_read_unlock(); |
0bc58a91 EB |
2219 | put_task_struct(start); |
2220 | return pos; | |
1da177e4 LT |
2221 | } |
2222 | ||
61a28784 EB |
2223 | static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir, |
2224 | struct task_struct *task, int tid) | |
2225 | { | |
2226 | char name[PROC_NUMBUF]; | |
2227 | int len = snprintf(name, sizeof(name), "%d", tid); | |
2228 | return proc_fill_cache(filp, dirent, filldir, name, len, | |
2229 | proc_task_instantiate, task, NULL); | |
2230 | } | |
2231 | ||
1da177e4 LT |
2232 | /* for the /proc/TGID/task/ directories */ |
2233 | static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir) | |
2234 | { | |
1da177e4 LT |
2235 | struct dentry *dentry = filp->f_dentry; |
2236 | struct inode *inode = dentry->d_inode; | |
99f89551 | 2237 | struct task_struct *leader = get_proc_task(inode); |
0bc58a91 | 2238 | struct task_struct *task; |
1da177e4 LT |
2239 | int retval = -ENOENT; |
2240 | ino_t ino; | |
0bc58a91 | 2241 | int tid; |
1da177e4 LT |
2242 | unsigned long pos = filp->f_pos; /* avoiding "long long" filp->f_pos */ |
2243 | ||
99f89551 EB |
2244 | if (!leader) |
2245 | goto out_no_task; | |
1da177e4 LT |
2246 | retval = 0; |
2247 | ||
2248 | switch (pos) { | |
2249 | case 0: | |
2250 | ino = inode->i_ino; | |
2251 | if (filldir(dirent, ".", 1, pos, ino, DT_DIR) < 0) | |
2252 | goto out; | |
2253 | pos++; | |
2254 | /* fall through */ | |
2255 | case 1: | |
2256 | ino = parent_ino(dentry); | |
2257 | if (filldir(dirent, "..", 2, pos, ino, DT_DIR) < 0) | |
2258 | goto out; | |
2259 | pos++; | |
2260 | /* fall through */ | |
2261 | } | |
2262 | ||
0bc58a91 EB |
2263 | /* f_version caches the tgid value that the last readdir call couldn't |
2264 | * return. lseek aka telldir automagically resets f_version to 0. | |
2265 | */ | |
2266 | tid = filp->f_version; | |
2267 | filp->f_version = 0; | |
2268 | for (task = first_tid(leader, tid, pos - 2); | |
2269 | task; | |
2270 | task = next_tid(task), pos++) { | |
0bc58a91 | 2271 | tid = task->pid; |
61a28784 | 2272 | if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) { |
0bc58a91 EB |
2273 | /* returning this tgid failed, save it as the first |
2274 | * pid for the next readir call */ | |
2275 | filp->f_version = tid; | |
2276 | put_task_struct(task); | |
1da177e4 | 2277 | break; |
0bc58a91 | 2278 | } |
1da177e4 LT |
2279 | } |
2280 | out: | |
2281 | filp->f_pos = pos; | |
99f89551 EB |
2282 | put_task_struct(leader); |
2283 | out_no_task: | |
1da177e4 LT |
2284 | return retval; |
2285 | } | |
6e66b52b EB |
2286 | |
2287 | static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) | |
2288 | { | |
2289 | struct inode *inode = dentry->d_inode; | |
99f89551 | 2290 | struct task_struct *p = get_proc_task(inode); |
6e66b52b EB |
2291 | generic_fillattr(inode, stat); |
2292 | ||
99f89551 EB |
2293 | if (p) { |
2294 | rcu_read_lock(); | |
2295 | stat->nlink += get_nr_threads(p); | |
2296 | rcu_read_unlock(); | |
2297 | put_task_struct(p); | |
6e66b52b EB |
2298 | } |
2299 | ||
2300 | return 0; | |
2301 | } | |
28a6d671 EB |
2302 | |
2303 | static struct inode_operations proc_task_inode_operations = { | |
2304 | .lookup = proc_task_lookup, | |
2305 | .getattr = proc_task_getattr, | |
2306 | .setattr = proc_setattr, | |
2307 | }; | |
2308 | ||
2309 | static struct file_operations proc_task_operations = { | |
2310 | .read = generic_read_dir, | |
2311 | .readdir = proc_task_readdir, | |
2312 | }; |