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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/errno.h> | |
53 | #include <linux/time.h> | |
54 | #include <linux/proc_fs.h> | |
55 | #include <linux/stat.h> | |
56 | #include <linux/task_io_accounting_ops.h> | |
57 | #include <linux/init.h> | |
58 | #include <linux/capability.h> | |
59 | #include <linux/file.h> | |
60 | #include <linux/fdtable.h> | |
61 | #include <linux/string.h> | |
62 | #include <linux/seq_file.h> | |
63 | #include <linux/namei.h> | |
64 | #include <linux/mnt_namespace.h> | |
65 | #include <linux/mm.h> | |
66 | #include <linux/rcupdate.h> | |
67 | #include <linux/kallsyms.h> | |
68 | #include <linux/stacktrace.h> | |
69 | #include <linux/resource.h> | |
70 | #include <linux/module.h> | |
71 | #include <linux/mount.h> | |
72 | #include <linux/security.h> | |
73 | #include <linux/ptrace.h> | |
74 | #include <linux/tracehook.h> | |
75 | #include <linux/cgroup.h> | |
76 | #include <linux/cpuset.h> | |
77 | #include <linux/audit.h> | |
78 | #include <linux/poll.h> | |
79 | #include <linux/nsproxy.h> | |
80 | #include <linux/oom.h> | |
81 | #include <linux/elf.h> | |
82 | #include <linux/pid_namespace.h> | |
83 | #include <linux/fs_struct.h> | |
84 | #include "internal.h" | |
85 | ||
86 | /* NOTE: | |
87 | * Implementing inode permission operations in /proc is almost | |
88 | * certainly an error. Permission checks need to happen during | |
89 | * each system call not at open time. The reason is that most of | |
90 | * what we wish to check for permissions in /proc varies at runtime. | |
91 | * | |
92 | * The classic example of a problem is opening file descriptors | |
93 | * in /proc for a task before it execs a suid executable. | |
94 | */ | |
95 | ||
96 | struct pid_entry { | |
97 | char *name; | |
98 | int len; | |
99 | mode_t mode; | |
100 | const struct inode_operations *iop; | |
101 | const struct file_operations *fop; | |
102 | union proc_op op; | |
103 | }; | |
104 | ||
105 | #define NOD(NAME, MODE, IOP, FOP, OP) { \ | |
106 | .name = (NAME), \ | |
107 | .len = sizeof(NAME) - 1, \ | |
108 | .mode = MODE, \ | |
109 | .iop = IOP, \ | |
110 | .fop = FOP, \ | |
111 | .op = OP, \ | |
112 | } | |
113 | ||
114 | #define DIR(NAME, MODE, iops, fops) \ | |
115 | NOD(NAME, (S_IFDIR|(MODE)), &iops, &fops, {} ) | |
116 | #define LNK(NAME, get_link) \ | |
117 | NOD(NAME, (S_IFLNK|S_IRWXUGO), \ | |
118 | &proc_pid_link_inode_operations, NULL, \ | |
119 | { .proc_get_link = get_link } ) | |
120 | #define REG(NAME, MODE, fops) \ | |
121 | NOD(NAME, (S_IFREG|(MODE)), NULL, &fops, {}) | |
122 | #define INF(NAME, MODE, read) \ | |
123 | NOD(NAME, (S_IFREG|(MODE)), \ | |
124 | NULL, &proc_info_file_operations, \ | |
125 | { .proc_read = read } ) | |
126 | #define ONE(NAME, MODE, show) \ | |
127 | NOD(NAME, (S_IFREG|(MODE)), \ | |
128 | NULL, &proc_single_file_operations, \ | |
129 | { .proc_show = show } ) | |
130 | ||
131 | /* | |
132 | * Count the number of hardlinks for the pid_entry table, excluding the . | |
133 | * and .. links. | |
134 | */ | |
135 | static unsigned int pid_entry_count_dirs(const struct pid_entry *entries, | |
136 | unsigned int n) | |
137 | { | |
138 | unsigned int i; | |
139 | unsigned int count; | |
140 | ||
141 | count = 0; | |
142 | for (i = 0; i < n; ++i) { | |
143 | if (S_ISDIR(entries[i].mode)) | |
144 | ++count; | |
145 | } | |
146 | ||
147 | return count; | |
148 | } | |
149 | ||
150 | static int get_fs_path(struct task_struct *task, struct path *path, bool root) | |
151 | { | |
152 | struct fs_struct *fs; | |
153 | int result = -ENOENT; | |
154 | ||
155 | task_lock(task); | |
156 | fs = task->fs; | |
157 | if (fs) { | |
158 | read_lock(&fs->lock); | |
159 | *path = root ? fs->root : fs->pwd; | |
160 | path_get(path); | |
161 | read_unlock(&fs->lock); | |
162 | result = 0; | |
163 | } | |
164 | task_unlock(task); | |
165 | return result; | |
166 | } | |
167 | ||
168 | static int get_nr_threads(struct task_struct *tsk) | |
169 | { | |
170 | unsigned long flags; | |
171 | int count = 0; | |
172 | ||
173 | if (lock_task_sighand(tsk, &flags)) { | |
174 | count = atomic_read(&tsk->signal->count); | |
175 | unlock_task_sighand(tsk, &flags); | |
176 | } | |
177 | return count; | |
178 | } | |
179 | ||
180 | static int proc_cwd_link(struct inode *inode, struct path *path) | |
181 | { | |
182 | struct task_struct *task = get_proc_task(inode); | |
183 | int result = -ENOENT; | |
184 | ||
185 | if (task) { | |
186 | result = get_fs_path(task, path, 0); | |
187 | put_task_struct(task); | |
188 | } | |
189 | return result; | |
190 | } | |
191 | ||
192 | static int proc_root_link(struct inode *inode, struct path *path) | |
193 | { | |
194 | struct task_struct *task = get_proc_task(inode); | |
195 | int result = -ENOENT; | |
196 | ||
197 | if (task) { | |
198 | result = get_fs_path(task, path, 1); | |
199 | put_task_struct(task); | |
200 | } | |
201 | return result; | |
202 | } | |
203 | ||
204 | /* | |
205 | * Return zero if current may access user memory in @task, -error if not. | |
206 | */ | |
207 | static int check_mem_permission(struct task_struct *task) | |
208 | { | |
209 | /* | |
210 | * A task can always look at itself, in case it chooses | |
211 | * to use system calls instead of load instructions. | |
212 | */ | |
213 | if (task == current) | |
214 | return 0; | |
215 | ||
216 | /* | |
217 | * If current is actively ptrace'ing, and would also be | |
218 | * permitted to freshly attach with ptrace now, permit it. | |
219 | */ | |
220 | if (task_is_stopped_or_traced(task)) { | |
221 | int match; | |
222 | rcu_read_lock(); | |
223 | match = (tracehook_tracer_task(task) == current); | |
224 | rcu_read_unlock(); | |
225 | if (match && ptrace_may_access(task, PTRACE_MODE_ATTACH)) | |
226 | return 0; | |
227 | } | |
228 | ||
229 | /* | |
230 | * Noone else is allowed. | |
231 | */ | |
232 | return -EPERM; | |
233 | } | |
234 | ||
235 | struct mm_struct *mm_for_maps(struct task_struct *task) | |
236 | { | |
237 | struct mm_struct *mm = get_task_mm(task); | |
238 | if (!mm) | |
239 | return NULL; | |
240 | down_read(&mm->mmap_sem); | |
241 | task_lock(task); | |
242 | if (task->mm != mm) | |
243 | goto out; | |
244 | if (task->mm != current->mm && | |
245 | __ptrace_may_access(task, PTRACE_MODE_READ) < 0) | |
246 | goto out; | |
247 | task_unlock(task); | |
248 | return mm; | |
249 | out: | |
250 | task_unlock(task); | |
251 | up_read(&mm->mmap_sem); | |
252 | mmput(mm); | |
253 | return NULL; | |
254 | } | |
255 | ||
256 | static int proc_pid_cmdline(struct task_struct *task, char * buffer) | |
257 | { | |
258 | int res = 0; | |
259 | unsigned int len; | |
260 | struct mm_struct *mm = get_task_mm(task); | |
261 | if (!mm) | |
262 | goto out; | |
263 | if (!mm->arg_end) | |
264 | goto out_mm; /* Shh! No looking before we're done */ | |
265 | ||
266 | len = mm->arg_end - mm->arg_start; | |
267 | ||
268 | if (len > PAGE_SIZE) | |
269 | len = PAGE_SIZE; | |
270 | ||
271 | res = access_process_vm(task, mm->arg_start, buffer, len, 0); | |
272 | ||
273 | // If the nul at the end of args has been overwritten, then | |
274 | // assume application is using setproctitle(3). | |
275 | if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) { | |
276 | len = strnlen(buffer, res); | |
277 | if (len < res) { | |
278 | res = len; | |
279 | } else { | |
280 | len = mm->env_end - mm->env_start; | |
281 | if (len > PAGE_SIZE - res) | |
282 | len = PAGE_SIZE - res; | |
283 | res += access_process_vm(task, mm->env_start, buffer+res, len, 0); | |
284 | res = strnlen(buffer, res); | |
285 | } | |
286 | } | |
287 | out_mm: | |
288 | mmput(mm); | |
289 | out: | |
290 | return res; | |
291 | } | |
292 | ||
293 | static int proc_pid_auxv(struct task_struct *task, char *buffer) | |
294 | { | |
295 | int res = 0; | |
296 | struct mm_struct *mm = get_task_mm(task); | |
297 | if (mm) { | |
298 | unsigned int nwords = 0; | |
299 | do { | |
300 | nwords += 2; | |
301 | } while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */ | |
302 | res = nwords * sizeof(mm->saved_auxv[0]); | |
303 | if (res > PAGE_SIZE) | |
304 | res = PAGE_SIZE; | |
305 | memcpy(buffer, mm->saved_auxv, res); | |
306 | mmput(mm); | |
307 | } | |
308 | return res; | |
309 | } | |
310 | ||
311 | ||
312 | #ifdef CONFIG_KALLSYMS | |
313 | /* | |
314 | * Provides a wchan file via kallsyms in a proper one-value-per-file format. | |
315 | * Returns the resolved symbol. If that fails, simply return the address. | |
316 | */ | |
317 | static int proc_pid_wchan(struct task_struct *task, char *buffer) | |
318 | { | |
319 | unsigned long wchan; | |
320 | char symname[KSYM_NAME_LEN]; | |
321 | ||
322 | wchan = get_wchan(task); | |
323 | ||
324 | if (lookup_symbol_name(wchan, symname) < 0) | |
325 | if (!ptrace_may_access(task, PTRACE_MODE_READ)) | |
326 | return 0; | |
327 | else | |
328 | return sprintf(buffer, "%lu", wchan); | |
329 | else | |
330 | return sprintf(buffer, "%s", symname); | |
331 | } | |
332 | #endif /* CONFIG_KALLSYMS */ | |
333 | ||
334 | #ifdef CONFIG_STACKTRACE | |
335 | ||
336 | #define MAX_STACK_TRACE_DEPTH 64 | |
337 | ||
338 | static int proc_pid_stack(struct seq_file *m, struct pid_namespace *ns, | |
339 | struct pid *pid, struct task_struct *task) | |
340 | { | |
341 | struct stack_trace trace; | |
342 | unsigned long *entries; | |
343 | int i; | |
344 | ||
345 | entries = kmalloc(MAX_STACK_TRACE_DEPTH * sizeof(*entries), GFP_KERNEL); | |
346 | if (!entries) | |
347 | return -ENOMEM; | |
348 | ||
349 | trace.nr_entries = 0; | |
350 | trace.max_entries = MAX_STACK_TRACE_DEPTH; | |
351 | trace.entries = entries; | |
352 | trace.skip = 0; | |
353 | save_stack_trace_tsk(task, &trace); | |
354 | ||
355 | for (i = 0; i < trace.nr_entries; i++) { | |
356 | seq_printf(m, "[<%p>] %pS\n", | |
357 | (void *)entries[i], (void *)entries[i]); | |
358 | } | |
359 | kfree(entries); | |
360 | ||
361 | return 0; | |
362 | } | |
363 | #endif | |
364 | ||
365 | #ifdef CONFIG_SCHEDSTATS | |
366 | /* | |
367 | * Provides /proc/PID/schedstat | |
368 | */ | |
369 | static int proc_pid_schedstat(struct task_struct *task, char *buffer) | |
370 | { | |
371 | return sprintf(buffer, "%llu %llu %lu\n", | |
372 | (unsigned long long)task->se.sum_exec_runtime, | |
373 | (unsigned long long)task->sched_info.run_delay, | |
374 | task->sched_info.pcount); | |
375 | } | |
376 | #endif | |
377 | ||
378 | #ifdef CONFIG_LATENCYTOP | |
379 | static int lstats_show_proc(struct seq_file *m, void *v) | |
380 | { | |
381 | int i; | |
382 | struct inode *inode = m->private; | |
383 | struct task_struct *task = get_proc_task(inode); | |
384 | ||
385 | if (!task) | |
386 | return -ESRCH; | |
387 | seq_puts(m, "Latency Top version : v0.1\n"); | |
388 | for (i = 0; i < 32; i++) { | |
389 | if (task->latency_record[i].backtrace[0]) { | |
390 | int q; | |
391 | seq_printf(m, "%i %li %li ", | |
392 | task->latency_record[i].count, | |
393 | task->latency_record[i].time, | |
394 | task->latency_record[i].max); | |
395 | for (q = 0; q < LT_BACKTRACEDEPTH; q++) { | |
396 | char sym[KSYM_SYMBOL_LEN]; | |
397 | char *c; | |
398 | if (!task->latency_record[i].backtrace[q]) | |
399 | break; | |
400 | if (task->latency_record[i].backtrace[q] == ULONG_MAX) | |
401 | break; | |
402 | sprint_symbol(sym, task->latency_record[i].backtrace[q]); | |
403 | c = strchr(sym, '+'); | |
404 | if (c) | |
405 | *c = 0; | |
406 | seq_printf(m, "%s ", sym); | |
407 | } | |
408 | seq_printf(m, "\n"); | |
409 | } | |
410 | ||
411 | } | |
412 | put_task_struct(task); | |
413 | return 0; | |
414 | } | |
415 | ||
416 | static int lstats_open(struct inode *inode, struct file *file) | |
417 | { | |
418 | return single_open(file, lstats_show_proc, inode); | |
419 | } | |
420 | ||
421 | static ssize_t lstats_write(struct file *file, const char __user *buf, | |
422 | size_t count, loff_t *offs) | |
423 | { | |
424 | struct task_struct *task = get_proc_task(file->f_dentry->d_inode); | |
425 | ||
426 | if (!task) | |
427 | return -ESRCH; | |
428 | clear_all_latency_tracing(task); | |
429 | put_task_struct(task); | |
430 | ||
431 | return count; | |
432 | } | |
433 | ||
434 | static const struct file_operations proc_lstats_operations = { | |
435 | .open = lstats_open, | |
436 | .read = seq_read, | |
437 | .write = lstats_write, | |
438 | .llseek = seq_lseek, | |
439 | .release = single_release, | |
440 | }; | |
441 | ||
442 | #endif | |
443 | ||
444 | /* The badness from the OOM killer */ | |
445 | unsigned long badness(struct task_struct *p, unsigned long uptime); | |
446 | static int proc_oom_score(struct task_struct *task, char *buffer) | |
447 | { | |
448 | unsigned long points; | |
449 | struct timespec uptime; | |
450 | ||
451 | do_posix_clock_monotonic_gettime(&uptime); | |
452 | read_lock(&tasklist_lock); | |
453 | points = badness(task, uptime.tv_sec); | |
454 | read_unlock(&tasklist_lock); | |
455 | return sprintf(buffer, "%lu\n", points); | |
456 | } | |
457 | ||
458 | struct limit_names { | |
459 | char *name; | |
460 | char *unit; | |
461 | }; | |
462 | ||
463 | static const struct limit_names lnames[RLIM_NLIMITS] = { | |
464 | [RLIMIT_CPU] = {"Max cpu time", "ms"}, | |
465 | [RLIMIT_FSIZE] = {"Max file size", "bytes"}, | |
466 | [RLIMIT_DATA] = {"Max data size", "bytes"}, | |
467 | [RLIMIT_STACK] = {"Max stack size", "bytes"}, | |
468 | [RLIMIT_CORE] = {"Max core file size", "bytes"}, | |
469 | [RLIMIT_RSS] = {"Max resident set", "bytes"}, | |
470 | [RLIMIT_NPROC] = {"Max processes", "processes"}, | |
471 | [RLIMIT_NOFILE] = {"Max open files", "files"}, | |
472 | [RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"}, | |
473 | [RLIMIT_AS] = {"Max address space", "bytes"}, | |
474 | [RLIMIT_LOCKS] = {"Max file locks", "locks"}, | |
475 | [RLIMIT_SIGPENDING] = {"Max pending signals", "signals"}, | |
476 | [RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"}, | |
477 | [RLIMIT_NICE] = {"Max nice priority", NULL}, | |
478 | [RLIMIT_RTPRIO] = {"Max realtime priority", NULL}, | |
479 | [RLIMIT_RTTIME] = {"Max realtime timeout", "us"}, | |
480 | }; | |
481 | ||
482 | /* Display limits for a process */ | |
483 | static int proc_pid_limits(struct task_struct *task, char *buffer) | |
484 | { | |
485 | unsigned int i; | |
486 | int count = 0; | |
487 | unsigned long flags; | |
488 | char *bufptr = buffer; | |
489 | ||
490 | struct rlimit rlim[RLIM_NLIMITS]; | |
491 | ||
492 | if (!lock_task_sighand(task, &flags)) | |
493 | return 0; | |
494 | memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS); | |
495 | unlock_task_sighand(task, &flags); | |
496 | ||
497 | /* | |
498 | * print the file header | |
499 | */ | |
500 | count += sprintf(&bufptr[count], "%-25s %-20s %-20s %-10s\n", | |
501 | "Limit", "Soft Limit", "Hard Limit", "Units"); | |
502 | ||
503 | for (i = 0; i < RLIM_NLIMITS; i++) { | |
504 | if (rlim[i].rlim_cur == RLIM_INFINITY) | |
505 | count += sprintf(&bufptr[count], "%-25s %-20s ", | |
506 | lnames[i].name, "unlimited"); | |
507 | else | |
508 | count += sprintf(&bufptr[count], "%-25s %-20lu ", | |
509 | lnames[i].name, rlim[i].rlim_cur); | |
510 | ||
511 | if (rlim[i].rlim_max == RLIM_INFINITY) | |
512 | count += sprintf(&bufptr[count], "%-20s ", "unlimited"); | |
513 | else | |
514 | count += sprintf(&bufptr[count], "%-20lu ", | |
515 | rlim[i].rlim_max); | |
516 | ||
517 | if (lnames[i].unit) | |
518 | count += sprintf(&bufptr[count], "%-10s\n", | |
519 | lnames[i].unit); | |
520 | else | |
521 | count += sprintf(&bufptr[count], "\n"); | |
522 | } | |
523 | ||
524 | return count; | |
525 | } | |
526 | ||
527 | #ifdef CONFIG_HAVE_ARCH_TRACEHOOK | |
528 | static int proc_pid_syscall(struct task_struct *task, char *buffer) | |
529 | { | |
530 | long nr; | |
531 | unsigned long args[6], sp, pc; | |
532 | ||
533 | if (task_current_syscall(task, &nr, args, 6, &sp, &pc)) | |
534 | return sprintf(buffer, "running\n"); | |
535 | ||
536 | if (nr < 0) | |
537 | return sprintf(buffer, "%ld 0x%lx 0x%lx\n", nr, sp, pc); | |
538 | ||
539 | return sprintf(buffer, | |
540 | "%ld 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx 0x%lx\n", | |
541 | nr, | |
542 | args[0], args[1], args[2], args[3], args[4], args[5], | |
543 | sp, pc); | |
544 | } | |
545 | #endif /* CONFIG_HAVE_ARCH_TRACEHOOK */ | |
546 | ||
547 | /************************************************************************/ | |
548 | /* Here the fs part begins */ | |
549 | /************************************************************************/ | |
550 | ||
551 | /* permission checks */ | |
552 | static int proc_fd_access_allowed(struct inode *inode) | |
553 | { | |
554 | struct task_struct *task; | |
555 | int allowed = 0; | |
556 | /* Allow access to a task's file descriptors if it is us or we | |
557 | * may use ptrace attach to the process and find out that | |
558 | * information. | |
559 | */ | |
560 | task = get_proc_task(inode); | |
561 | if (task) { | |
562 | allowed = ptrace_may_access(task, PTRACE_MODE_READ); | |
563 | put_task_struct(task); | |
564 | } | |
565 | return allowed; | |
566 | } | |
567 | ||
568 | static int proc_setattr(struct dentry *dentry, struct iattr *attr) | |
569 | { | |
570 | int error; | |
571 | struct inode *inode = dentry->d_inode; | |
572 | ||
573 | if (attr->ia_valid & ATTR_MODE) | |
574 | return -EPERM; | |
575 | ||
576 | error = inode_change_ok(inode, attr); | |
577 | if (!error) | |
578 | error = inode_setattr(inode, attr); | |
579 | return error; | |
580 | } | |
581 | ||
582 | static const struct inode_operations proc_def_inode_operations = { | |
583 | .setattr = proc_setattr, | |
584 | }; | |
585 | ||
586 | static int mounts_open_common(struct inode *inode, struct file *file, | |
587 | const struct seq_operations *op) | |
588 | { | |
589 | struct task_struct *task = get_proc_task(inode); | |
590 | struct nsproxy *nsp; | |
591 | struct mnt_namespace *ns = NULL; | |
592 | struct path root; | |
593 | struct proc_mounts *p; | |
594 | int ret = -EINVAL; | |
595 | ||
596 | if (task) { | |
597 | rcu_read_lock(); | |
598 | nsp = task_nsproxy(task); | |
599 | if (nsp) { | |
600 | ns = nsp->mnt_ns; | |
601 | if (ns) | |
602 | get_mnt_ns(ns); | |
603 | } | |
604 | rcu_read_unlock(); | |
605 | if (ns && get_fs_path(task, &root, 1) == 0) | |
606 | ret = 0; | |
607 | put_task_struct(task); | |
608 | } | |
609 | ||
610 | if (!ns) | |
611 | goto err; | |
612 | if (ret) | |
613 | goto err_put_ns; | |
614 | ||
615 | ret = -ENOMEM; | |
616 | p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL); | |
617 | if (!p) | |
618 | goto err_put_path; | |
619 | ||
620 | file->private_data = &p->m; | |
621 | ret = seq_open(file, op); | |
622 | if (ret) | |
623 | goto err_free; | |
624 | ||
625 | p->m.private = p; | |
626 | p->ns = ns; | |
627 | p->root = root; | |
628 | p->event = ns->event; | |
629 | ||
630 | return 0; | |
631 | ||
632 | err_free: | |
633 | kfree(p); | |
634 | err_put_path: | |
635 | path_put(&root); | |
636 | err_put_ns: | |
637 | put_mnt_ns(ns); | |
638 | err: | |
639 | return ret; | |
640 | } | |
641 | ||
642 | static int mounts_release(struct inode *inode, struct file *file) | |
643 | { | |
644 | struct proc_mounts *p = file->private_data; | |
645 | path_put(&p->root); | |
646 | put_mnt_ns(p->ns); | |
647 | return seq_release(inode, file); | |
648 | } | |
649 | ||
650 | static unsigned mounts_poll(struct file *file, poll_table *wait) | |
651 | { | |
652 | struct proc_mounts *p = file->private_data; | |
653 | struct mnt_namespace *ns = p->ns; | |
654 | unsigned res = POLLIN | POLLRDNORM; | |
655 | ||
656 | poll_wait(file, &ns->poll, wait); | |
657 | ||
658 | spin_lock(&vfsmount_lock); | |
659 | if (p->event != ns->event) { | |
660 | p->event = ns->event; | |
661 | res |= POLLERR | POLLPRI; | |
662 | } | |
663 | spin_unlock(&vfsmount_lock); | |
664 | ||
665 | return res; | |
666 | } | |
667 | ||
668 | static int mounts_open(struct inode *inode, struct file *file) | |
669 | { | |
670 | return mounts_open_common(inode, file, &mounts_op); | |
671 | } | |
672 | ||
673 | static const struct file_operations proc_mounts_operations = { | |
674 | .open = mounts_open, | |
675 | .read = seq_read, | |
676 | .llseek = seq_lseek, | |
677 | .release = mounts_release, | |
678 | .poll = mounts_poll, | |
679 | }; | |
680 | ||
681 | static int mountinfo_open(struct inode *inode, struct file *file) | |
682 | { | |
683 | return mounts_open_common(inode, file, &mountinfo_op); | |
684 | } | |
685 | ||
686 | static const struct file_operations proc_mountinfo_operations = { | |
687 | .open = mountinfo_open, | |
688 | .read = seq_read, | |
689 | .llseek = seq_lseek, | |
690 | .release = mounts_release, | |
691 | .poll = mounts_poll, | |
692 | }; | |
693 | ||
694 | static int mountstats_open(struct inode *inode, struct file *file) | |
695 | { | |
696 | return mounts_open_common(inode, file, &mountstats_op); | |
697 | } | |
698 | ||
699 | static const struct file_operations proc_mountstats_operations = { | |
700 | .open = mountstats_open, | |
701 | .read = seq_read, | |
702 | .llseek = seq_lseek, | |
703 | .release = mounts_release, | |
704 | }; | |
705 | ||
706 | #define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */ | |
707 | ||
708 | static ssize_t proc_info_read(struct file * file, char __user * buf, | |
709 | size_t count, loff_t *ppos) | |
710 | { | |
711 | struct inode * inode = file->f_path.dentry->d_inode; | |
712 | unsigned long page; | |
713 | ssize_t length; | |
714 | struct task_struct *task = get_proc_task(inode); | |
715 | ||
716 | length = -ESRCH; | |
717 | if (!task) | |
718 | goto out_no_task; | |
719 | ||
720 | if (count > PROC_BLOCK_SIZE) | |
721 | count = PROC_BLOCK_SIZE; | |
722 | ||
723 | length = -ENOMEM; | |
724 | if (!(page = __get_free_page(GFP_TEMPORARY))) | |
725 | goto out; | |
726 | ||
727 | length = PROC_I(inode)->op.proc_read(task, (char*)page); | |
728 | ||
729 | if (length >= 0) | |
730 | length = simple_read_from_buffer(buf, count, ppos, (char *)page, length); | |
731 | free_page(page); | |
732 | out: | |
733 | put_task_struct(task); | |
734 | out_no_task: | |
735 | return length; | |
736 | } | |
737 | ||
738 | static const struct file_operations proc_info_file_operations = { | |
739 | .read = proc_info_read, | |
740 | }; | |
741 | ||
742 | static int proc_single_show(struct seq_file *m, void *v) | |
743 | { | |
744 | struct inode *inode = m->private; | |
745 | struct pid_namespace *ns; | |
746 | struct pid *pid; | |
747 | struct task_struct *task; | |
748 | int ret; | |
749 | ||
750 | ns = inode->i_sb->s_fs_info; | |
751 | pid = proc_pid(inode); | |
752 | task = get_pid_task(pid, PIDTYPE_PID); | |
753 | if (!task) | |
754 | return -ESRCH; | |
755 | ||
756 | ret = PROC_I(inode)->op.proc_show(m, ns, pid, task); | |
757 | ||
758 | put_task_struct(task); | |
759 | return ret; | |
760 | } | |
761 | ||
762 | static int proc_single_open(struct inode *inode, struct file *filp) | |
763 | { | |
764 | int ret; | |
765 | ret = single_open(filp, proc_single_show, NULL); | |
766 | if (!ret) { | |
767 | struct seq_file *m = filp->private_data; | |
768 | ||
769 | m->private = inode; | |
770 | } | |
771 | return ret; | |
772 | } | |
773 | ||
774 | static const struct file_operations proc_single_file_operations = { | |
775 | .open = proc_single_open, | |
776 | .read = seq_read, | |
777 | .llseek = seq_lseek, | |
778 | .release = single_release, | |
779 | }; | |
780 | ||
781 | static int mem_open(struct inode* inode, struct file* file) | |
782 | { | |
783 | file->private_data = (void*)((long)current->self_exec_id); | |
784 | return 0; | |
785 | } | |
786 | ||
787 | static ssize_t mem_read(struct file * file, char __user * buf, | |
788 | size_t count, loff_t *ppos) | |
789 | { | |
790 | struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); | |
791 | char *page; | |
792 | unsigned long src = *ppos; | |
793 | int ret = -ESRCH; | |
794 | struct mm_struct *mm; | |
795 | ||
796 | if (!task) | |
797 | goto out_no_task; | |
798 | ||
799 | if (check_mem_permission(task)) | |
800 | goto out; | |
801 | ||
802 | ret = -ENOMEM; | |
803 | page = (char *)__get_free_page(GFP_TEMPORARY); | |
804 | if (!page) | |
805 | goto out; | |
806 | ||
807 | ret = 0; | |
808 | ||
809 | mm = get_task_mm(task); | |
810 | if (!mm) | |
811 | goto out_free; | |
812 | ||
813 | ret = -EIO; | |
814 | ||
815 | if (file->private_data != (void*)((long)current->self_exec_id)) | |
816 | goto out_put; | |
817 | ||
818 | ret = 0; | |
819 | ||
820 | while (count > 0) { | |
821 | int this_len, retval; | |
822 | ||
823 | this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; | |
824 | retval = access_process_vm(task, src, page, this_len, 0); | |
825 | if (!retval || check_mem_permission(task)) { | |
826 | if (!ret) | |
827 | ret = -EIO; | |
828 | break; | |
829 | } | |
830 | ||
831 | if (copy_to_user(buf, page, retval)) { | |
832 | ret = -EFAULT; | |
833 | break; | |
834 | } | |
835 | ||
836 | ret += retval; | |
837 | src += retval; | |
838 | buf += retval; | |
839 | count -= retval; | |
840 | } | |
841 | *ppos = src; | |
842 | ||
843 | out_put: | |
844 | mmput(mm); | |
845 | out_free: | |
846 | free_page((unsigned long) page); | |
847 | out: | |
848 | put_task_struct(task); | |
849 | out_no_task: | |
850 | return ret; | |
851 | } | |
852 | ||
853 | #define mem_write NULL | |
854 | ||
855 | #ifndef mem_write | |
856 | /* This is a security hazard */ | |
857 | static ssize_t mem_write(struct file * file, const char __user *buf, | |
858 | size_t count, loff_t *ppos) | |
859 | { | |
860 | int copied; | |
861 | char *page; | |
862 | struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); | |
863 | unsigned long dst = *ppos; | |
864 | ||
865 | copied = -ESRCH; | |
866 | if (!task) | |
867 | goto out_no_task; | |
868 | ||
869 | if (check_mem_permission(task)) | |
870 | goto out; | |
871 | ||
872 | copied = -ENOMEM; | |
873 | page = (char *)__get_free_page(GFP_TEMPORARY); | |
874 | if (!page) | |
875 | goto out; | |
876 | ||
877 | copied = 0; | |
878 | while (count > 0) { | |
879 | int this_len, retval; | |
880 | ||
881 | this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; | |
882 | if (copy_from_user(page, buf, this_len)) { | |
883 | copied = -EFAULT; | |
884 | break; | |
885 | } | |
886 | retval = access_process_vm(task, dst, page, this_len, 1); | |
887 | if (!retval) { | |
888 | if (!copied) | |
889 | copied = -EIO; | |
890 | break; | |
891 | } | |
892 | copied += retval; | |
893 | buf += retval; | |
894 | dst += retval; | |
895 | count -= retval; | |
896 | } | |
897 | *ppos = dst; | |
898 | free_page((unsigned long) page); | |
899 | out: | |
900 | put_task_struct(task); | |
901 | out_no_task: | |
902 | return copied; | |
903 | } | |
904 | #endif | |
905 | ||
906 | loff_t mem_lseek(struct file *file, loff_t offset, int orig) | |
907 | { | |
908 | switch (orig) { | |
909 | case 0: | |
910 | file->f_pos = offset; | |
911 | break; | |
912 | case 1: | |
913 | file->f_pos += offset; | |
914 | break; | |
915 | default: | |
916 | return -EINVAL; | |
917 | } | |
918 | force_successful_syscall_return(); | |
919 | return file->f_pos; | |
920 | } | |
921 | ||
922 | static const struct file_operations proc_mem_operations = { | |
923 | .llseek = mem_lseek, | |
924 | .read = mem_read, | |
925 | .write = mem_write, | |
926 | .open = mem_open, | |
927 | }; | |
928 | ||
929 | static ssize_t environ_read(struct file *file, char __user *buf, | |
930 | size_t count, loff_t *ppos) | |
931 | { | |
932 | struct task_struct *task = get_proc_task(file->f_dentry->d_inode); | |
933 | char *page; | |
934 | unsigned long src = *ppos; | |
935 | int ret = -ESRCH; | |
936 | struct mm_struct *mm; | |
937 | ||
938 | if (!task) | |
939 | goto out_no_task; | |
940 | ||
941 | if (!ptrace_may_access(task, PTRACE_MODE_READ)) | |
942 | goto out; | |
943 | ||
944 | ret = -ENOMEM; | |
945 | page = (char *)__get_free_page(GFP_TEMPORARY); | |
946 | if (!page) | |
947 | goto out; | |
948 | ||
949 | ret = 0; | |
950 | ||
951 | mm = get_task_mm(task); | |
952 | if (!mm) | |
953 | goto out_free; | |
954 | ||
955 | while (count > 0) { | |
956 | int this_len, retval, max_len; | |
957 | ||
958 | this_len = mm->env_end - (mm->env_start + src); | |
959 | ||
960 | if (this_len <= 0) | |
961 | break; | |
962 | ||
963 | max_len = (count > PAGE_SIZE) ? PAGE_SIZE : count; | |
964 | this_len = (this_len > max_len) ? max_len : this_len; | |
965 | ||
966 | retval = access_process_vm(task, (mm->env_start + src), | |
967 | page, this_len, 0); | |
968 | ||
969 | if (retval <= 0) { | |
970 | ret = retval; | |
971 | break; | |
972 | } | |
973 | ||
974 | if (copy_to_user(buf, page, retval)) { | |
975 | ret = -EFAULT; | |
976 | break; | |
977 | } | |
978 | ||
979 | ret += retval; | |
980 | src += retval; | |
981 | buf += retval; | |
982 | count -= retval; | |
983 | } | |
984 | *ppos = src; | |
985 | ||
986 | mmput(mm); | |
987 | out_free: | |
988 | free_page((unsigned long) page); | |
989 | out: | |
990 | put_task_struct(task); | |
991 | out_no_task: | |
992 | return ret; | |
993 | } | |
994 | ||
995 | static const struct file_operations proc_environ_operations = { | |
996 | .read = environ_read, | |
997 | }; | |
998 | ||
999 | static ssize_t oom_adjust_read(struct file *file, char __user *buf, | |
1000 | size_t count, loff_t *ppos) | |
1001 | { | |
1002 | struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode); | |
1003 | char buffer[PROC_NUMBUF]; | |
1004 | size_t len; | |
1005 | int oom_adjust; | |
1006 | ||
1007 | if (!task) | |
1008 | return -ESRCH; | |
1009 | oom_adjust = task->oomkilladj; | |
1010 | put_task_struct(task); | |
1011 | ||
1012 | len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust); | |
1013 | ||
1014 | return simple_read_from_buffer(buf, count, ppos, buffer, len); | |
1015 | } | |
1016 | ||
1017 | static ssize_t oom_adjust_write(struct file *file, const char __user *buf, | |
1018 | size_t count, loff_t *ppos) | |
1019 | { | |
1020 | struct task_struct *task; | |
1021 | char buffer[PROC_NUMBUF], *end; | |
1022 | int oom_adjust; | |
1023 | ||
1024 | memset(buffer, 0, sizeof(buffer)); | |
1025 | if (count > sizeof(buffer) - 1) | |
1026 | count = sizeof(buffer) - 1; | |
1027 | if (copy_from_user(buffer, buf, count)) | |
1028 | return -EFAULT; | |
1029 | oom_adjust = simple_strtol(buffer, &end, 0); | |
1030 | if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) && | |
1031 | oom_adjust != OOM_DISABLE) | |
1032 | return -EINVAL; | |
1033 | if (*end == '\n') | |
1034 | end++; | |
1035 | task = get_proc_task(file->f_path.dentry->d_inode); | |
1036 | if (!task) | |
1037 | return -ESRCH; | |
1038 | if (oom_adjust < task->oomkilladj && !capable(CAP_SYS_RESOURCE)) { | |
1039 | put_task_struct(task); | |
1040 | return -EACCES; | |
1041 | } | |
1042 | task->oomkilladj = oom_adjust; | |
1043 | put_task_struct(task); | |
1044 | if (end - buffer == 0) | |
1045 | return -EIO; | |
1046 | return end - buffer; | |
1047 | } | |
1048 | ||
1049 | static const struct file_operations proc_oom_adjust_operations = { | |
1050 | .read = oom_adjust_read, | |
1051 | .write = oom_adjust_write, | |
1052 | }; | |
1053 | ||
1054 | #ifdef CONFIG_AUDITSYSCALL | |
1055 | #define TMPBUFLEN 21 | |
1056 | static ssize_t proc_loginuid_read(struct file * file, char __user * buf, | |
1057 | size_t count, loff_t *ppos) | |
1058 | { | |
1059 | struct inode * inode = file->f_path.dentry->d_inode; | |
1060 | struct task_struct *task = get_proc_task(inode); | |
1061 | ssize_t length; | |
1062 | char tmpbuf[TMPBUFLEN]; | |
1063 | ||
1064 | if (!task) | |
1065 | return -ESRCH; | |
1066 | length = scnprintf(tmpbuf, TMPBUFLEN, "%u", | |
1067 | audit_get_loginuid(task)); | |
1068 | put_task_struct(task); | |
1069 | return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); | |
1070 | } | |
1071 | ||
1072 | static ssize_t proc_loginuid_write(struct file * file, const char __user * buf, | |
1073 | size_t count, loff_t *ppos) | |
1074 | { | |
1075 | struct inode * inode = file->f_path.dentry->d_inode; | |
1076 | char *page, *tmp; | |
1077 | ssize_t length; | |
1078 | uid_t loginuid; | |
1079 | ||
1080 | if (!capable(CAP_AUDIT_CONTROL)) | |
1081 | return -EPERM; | |
1082 | ||
1083 | if (current != pid_task(proc_pid(inode), PIDTYPE_PID)) | |
1084 | return -EPERM; | |
1085 | ||
1086 | if (count >= PAGE_SIZE) | |
1087 | count = PAGE_SIZE - 1; | |
1088 | ||
1089 | if (*ppos != 0) { | |
1090 | /* No partial writes. */ | |
1091 | return -EINVAL; | |
1092 | } | |
1093 | page = (char*)__get_free_page(GFP_TEMPORARY); | |
1094 | if (!page) | |
1095 | return -ENOMEM; | |
1096 | length = -EFAULT; | |
1097 | if (copy_from_user(page, buf, count)) | |
1098 | goto out_free_page; | |
1099 | ||
1100 | page[count] = '\0'; | |
1101 | loginuid = simple_strtoul(page, &tmp, 10); | |
1102 | if (tmp == page) { | |
1103 | length = -EINVAL; | |
1104 | goto out_free_page; | |
1105 | ||
1106 | } | |
1107 | length = audit_set_loginuid(current, loginuid); | |
1108 | if (likely(length == 0)) | |
1109 | length = count; | |
1110 | ||
1111 | out_free_page: | |
1112 | free_page((unsigned long) page); | |
1113 | return length; | |
1114 | } | |
1115 | ||
1116 | static const struct file_operations proc_loginuid_operations = { | |
1117 | .read = proc_loginuid_read, | |
1118 | .write = proc_loginuid_write, | |
1119 | }; | |
1120 | ||
1121 | static ssize_t proc_sessionid_read(struct file * file, char __user * buf, | |
1122 | size_t count, loff_t *ppos) | |
1123 | { | |
1124 | struct inode * inode = file->f_path.dentry->d_inode; | |
1125 | struct task_struct *task = get_proc_task(inode); | |
1126 | ssize_t length; | |
1127 | char tmpbuf[TMPBUFLEN]; | |
1128 | ||
1129 | if (!task) | |
1130 | return -ESRCH; | |
1131 | length = scnprintf(tmpbuf, TMPBUFLEN, "%u", | |
1132 | audit_get_sessionid(task)); | |
1133 | put_task_struct(task); | |
1134 | return simple_read_from_buffer(buf, count, ppos, tmpbuf, length); | |
1135 | } | |
1136 | ||
1137 | static const struct file_operations proc_sessionid_operations = { | |
1138 | .read = proc_sessionid_read, | |
1139 | }; | |
1140 | #endif | |
1141 | ||
1142 | #ifdef CONFIG_FAULT_INJECTION | |
1143 | static ssize_t proc_fault_inject_read(struct file * file, char __user * buf, | |
1144 | size_t count, loff_t *ppos) | |
1145 | { | |
1146 | struct task_struct *task = get_proc_task(file->f_dentry->d_inode); | |
1147 | char buffer[PROC_NUMBUF]; | |
1148 | size_t len; | |
1149 | int make_it_fail; | |
1150 | ||
1151 | if (!task) | |
1152 | return -ESRCH; | |
1153 | make_it_fail = task->make_it_fail; | |
1154 | put_task_struct(task); | |
1155 | ||
1156 | len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail); | |
1157 | ||
1158 | return simple_read_from_buffer(buf, count, ppos, buffer, len); | |
1159 | } | |
1160 | ||
1161 | static ssize_t proc_fault_inject_write(struct file * file, | |
1162 | const char __user * buf, size_t count, loff_t *ppos) | |
1163 | { | |
1164 | struct task_struct *task; | |
1165 | char buffer[PROC_NUMBUF], *end; | |
1166 | int make_it_fail; | |
1167 | ||
1168 | if (!capable(CAP_SYS_RESOURCE)) | |
1169 | return -EPERM; | |
1170 | memset(buffer, 0, sizeof(buffer)); | |
1171 | if (count > sizeof(buffer) - 1) | |
1172 | count = sizeof(buffer) - 1; | |
1173 | if (copy_from_user(buffer, buf, count)) | |
1174 | return -EFAULT; | |
1175 | make_it_fail = simple_strtol(buffer, &end, 0); | |
1176 | if (*end == '\n') | |
1177 | end++; | |
1178 | task = get_proc_task(file->f_dentry->d_inode); | |
1179 | if (!task) | |
1180 | return -ESRCH; | |
1181 | task->make_it_fail = make_it_fail; | |
1182 | put_task_struct(task); | |
1183 | if (end - buffer == 0) | |
1184 | return -EIO; | |
1185 | return end - buffer; | |
1186 | } | |
1187 | ||
1188 | static const struct file_operations proc_fault_inject_operations = { | |
1189 | .read = proc_fault_inject_read, | |
1190 | .write = proc_fault_inject_write, | |
1191 | }; | |
1192 | #endif | |
1193 | ||
1194 | ||
1195 | #ifdef CONFIG_SCHED_DEBUG | |
1196 | /* | |
1197 | * Print out various scheduling related per-task fields: | |
1198 | */ | |
1199 | static int sched_show(struct seq_file *m, void *v) | |
1200 | { | |
1201 | struct inode *inode = m->private; | |
1202 | struct task_struct *p; | |
1203 | ||
1204 | p = get_proc_task(inode); | |
1205 | if (!p) | |
1206 | return -ESRCH; | |
1207 | proc_sched_show_task(p, m); | |
1208 | ||
1209 | put_task_struct(p); | |
1210 | ||
1211 | return 0; | |
1212 | } | |
1213 | ||
1214 | static ssize_t | |
1215 | sched_write(struct file *file, const char __user *buf, | |
1216 | size_t count, loff_t *offset) | |
1217 | { | |
1218 | struct inode *inode = file->f_path.dentry->d_inode; | |
1219 | struct task_struct *p; | |
1220 | ||
1221 | p = get_proc_task(inode); | |
1222 | if (!p) | |
1223 | return -ESRCH; | |
1224 | proc_sched_set_task(p); | |
1225 | ||
1226 | put_task_struct(p); | |
1227 | ||
1228 | return count; | |
1229 | } | |
1230 | ||
1231 | static int sched_open(struct inode *inode, struct file *filp) | |
1232 | { | |
1233 | int ret; | |
1234 | ||
1235 | ret = single_open(filp, sched_show, NULL); | |
1236 | if (!ret) { | |
1237 | struct seq_file *m = filp->private_data; | |
1238 | ||
1239 | m->private = inode; | |
1240 | } | |
1241 | return ret; | |
1242 | } | |
1243 | ||
1244 | static const struct file_operations proc_pid_sched_operations = { | |
1245 | .open = sched_open, | |
1246 | .read = seq_read, | |
1247 | .write = sched_write, | |
1248 | .llseek = seq_lseek, | |
1249 | .release = single_release, | |
1250 | }; | |
1251 | ||
1252 | #endif | |
1253 | ||
1254 | /* | |
1255 | * We added or removed a vma mapping the executable. The vmas are only mapped | |
1256 | * during exec and are not mapped with the mmap system call. | |
1257 | * Callers must hold down_write() on the mm's mmap_sem for these | |
1258 | */ | |
1259 | void added_exe_file_vma(struct mm_struct *mm) | |
1260 | { | |
1261 | mm->num_exe_file_vmas++; | |
1262 | } | |
1263 | ||
1264 | void removed_exe_file_vma(struct mm_struct *mm) | |
1265 | { | |
1266 | mm->num_exe_file_vmas--; | |
1267 | if ((mm->num_exe_file_vmas == 0) && mm->exe_file){ | |
1268 | fput(mm->exe_file); | |
1269 | mm->exe_file = NULL; | |
1270 | } | |
1271 | ||
1272 | } | |
1273 | ||
1274 | void set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file) | |
1275 | { | |
1276 | if (new_exe_file) | |
1277 | get_file(new_exe_file); | |
1278 | if (mm->exe_file) | |
1279 | fput(mm->exe_file); | |
1280 | mm->exe_file = new_exe_file; | |
1281 | mm->num_exe_file_vmas = 0; | |
1282 | } | |
1283 | ||
1284 | struct file *get_mm_exe_file(struct mm_struct *mm) | |
1285 | { | |
1286 | struct file *exe_file; | |
1287 | ||
1288 | /* We need mmap_sem to protect against races with removal of | |
1289 | * VM_EXECUTABLE vmas */ | |
1290 | down_read(&mm->mmap_sem); | |
1291 | exe_file = mm->exe_file; | |
1292 | if (exe_file) | |
1293 | get_file(exe_file); | |
1294 | up_read(&mm->mmap_sem); | |
1295 | return exe_file; | |
1296 | } | |
1297 | ||
1298 | void dup_mm_exe_file(struct mm_struct *oldmm, struct mm_struct *newmm) | |
1299 | { | |
1300 | /* It's safe to write the exe_file pointer without exe_file_lock because | |
1301 | * this is called during fork when the task is not yet in /proc */ | |
1302 | newmm->exe_file = get_mm_exe_file(oldmm); | |
1303 | } | |
1304 | ||
1305 | static int proc_exe_link(struct inode *inode, struct path *exe_path) | |
1306 | { | |
1307 | struct task_struct *task; | |
1308 | struct mm_struct *mm; | |
1309 | struct file *exe_file; | |
1310 | ||
1311 | task = get_proc_task(inode); | |
1312 | if (!task) | |
1313 | return -ENOENT; | |
1314 | mm = get_task_mm(task); | |
1315 | put_task_struct(task); | |
1316 | if (!mm) | |
1317 | return -ENOENT; | |
1318 | exe_file = get_mm_exe_file(mm); | |
1319 | mmput(mm); | |
1320 | if (exe_file) { | |
1321 | *exe_path = exe_file->f_path; | |
1322 | path_get(&exe_file->f_path); | |
1323 | fput(exe_file); | |
1324 | return 0; | |
1325 | } else | |
1326 | return -ENOENT; | |
1327 | } | |
1328 | ||
1329 | static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd) | |
1330 | { | |
1331 | struct inode *inode = dentry->d_inode; | |
1332 | int error = -EACCES; | |
1333 | ||
1334 | /* We don't need a base pointer in the /proc filesystem */ | |
1335 | path_put(&nd->path); | |
1336 | ||
1337 | /* Are we allowed to snoop on the tasks file descriptors? */ | |
1338 | if (!proc_fd_access_allowed(inode)) | |
1339 | goto out; | |
1340 | ||
1341 | error = PROC_I(inode)->op.proc_get_link(inode, &nd->path); | |
1342 | nd->last_type = LAST_BIND; | |
1343 | out: | |
1344 | return ERR_PTR(error); | |
1345 | } | |
1346 | ||
1347 | static int do_proc_readlink(struct path *path, char __user *buffer, int buflen) | |
1348 | { | |
1349 | char *tmp = (char*)__get_free_page(GFP_TEMPORARY); | |
1350 | char *pathname; | |
1351 | int len; | |
1352 | ||
1353 | if (!tmp) | |
1354 | return -ENOMEM; | |
1355 | ||
1356 | pathname = d_path(path, tmp, PAGE_SIZE); | |
1357 | len = PTR_ERR(pathname); | |
1358 | if (IS_ERR(pathname)) | |
1359 | goto out; | |
1360 | len = tmp + PAGE_SIZE - 1 - pathname; | |
1361 | ||
1362 | if (len > buflen) | |
1363 | len = buflen; | |
1364 | if (copy_to_user(buffer, pathname, len)) | |
1365 | len = -EFAULT; | |
1366 | out: | |
1367 | free_page((unsigned long)tmp); | |
1368 | return len; | |
1369 | } | |
1370 | ||
1371 | static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen) | |
1372 | { | |
1373 | int error = -EACCES; | |
1374 | struct inode *inode = dentry->d_inode; | |
1375 | struct path path; | |
1376 | ||
1377 | /* Are we allowed to snoop on the tasks file descriptors? */ | |
1378 | if (!proc_fd_access_allowed(inode)) | |
1379 | goto out; | |
1380 | ||
1381 | error = PROC_I(inode)->op.proc_get_link(inode, &path); | |
1382 | if (error) | |
1383 | goto out; | |
1384 | ||
1385 | error = do_proc_readlink(&path, buffer, buflen); | |
1386 | path_put(&path); | |
1387 | out: | |
1388 | return error; | |
1389 | } | |
1390 | ||
1391 | static const struct inode_operations proc_pid_link_inode_operations = { | |
1392 | .readlink = proc_pid_readlink, | |
1393 | .follow_link = proc_pid_follow_link, | |
1394 | .setattr = proc_setattr, | |
1395 | }; | |
1396 | ||
1397 | ||
1398 | /* building an inode */ | |
1399 | ||
1400 | static int task_dumpable(struct task_struct *task) | |
1401 | { | |
1402 | int dumpable = 0; | |
1403 | struct mm_struct *mm; | |
1404 | ||
1405 | task_lock(task); | |
1406 | mm = task->mm; | |
1407 | if (mm) | |
1408 | dumpable = get_dumpable(mm); | |
1409 | task_unlock(task); | |
1410 | if(dumpable == 1) | |
1411 | return 1; | |
1412 | return 0; | |
1413 | } | |
1414 | ||
1415 | ||
1416 | static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task) | |
1417 | { | |
1418 | struct inode * inode; | |
1419 | struct proc_inode *ei; | |
1420 | const struct cred *cred; | |
1421 | ||
1422 | /* We need a new inode */ | |
1423 | ||
1424 | inode = new_inode(sb); | |
1425 | if (!inode) | |
1426 | goto out; | |
1427 | ||
1428 | /* Common stuff */ | |
1429 | ei = PROC_I(inode); | |
1430 | inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; | |
1431 | inode->i_op = &proc_def_inode_operations; | |
1432 | ||
1433 | /* | |
1434 | * grab the reference to task. | |
1435 | */ | |
1436 | ei->pid = get_task_pid(task, PIDTYPE_PID); | |
1437 | if (!ei->pid) | |
1438 | goto out_unlock; | |
1439 | ||
1440 | if (task_dumpable(task)) { | |
1441 | rcu_read_lock(); | |
1442 | cred = __task_cred(task); | |
1443 | inode->i_uid = cred->euid; | |
1444 | inode->i_gid = cred->egid; | |
1445 | rcu_read_unlock(); | |
1446 | } | |
1447 | security_task_to_inode(task, inode); | |
1448 | ||
1449 | out: | |
1450 | return inode; | |
1451 | ||
1452 | out_unlock: | |
1453 | iput(inode); | |
1454 | return NULL; | |
1455 | } | |
1456 | ||
1457 | static int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) | |
1458 | { | |
1459 | struct inode *inode = dentry->d_inode; | |
1460 | struct task_struct *task; | |
1461 | const struct cred *cred; | |
1462 | ||
1463 | generic_fillattr(inode, stat); | |
1464 | ||
1465 | rcu_read_lock(); | |
1466 | stat->uid = 0; | |
1467 | stat->gid = 0; | |
1468 | task = pid_task(proc_pid(inode), PIDTYPE_PID); | |
1469 | if (task) { | |
1470 | if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || | |
1471 | task_dumpable(task)) { | |
1472 | cred = __task_cred(task); | |
1473 | stat->uid = cred->euid; | |
1474 | stat->gid = cred->egid; | |
1475 | } | |
1476 | } | |
1477 | rcu_read_unlock(); | |
1478 | return 0; | |
1479 | } | |
1480 | ||
1481 | /* dentry stuff */ | |
1482 | ||
1483 | /* | |
1484 | * Exceptional case: normally we are not allowed to unhash a busy | |
1485 | * directory. In this case, however, we can do it - no aliasing problems | |
1486 | * due to the way we treat inodes. | |
1487 | * | |
1488 | * Rewrite the inode's ownerships here because the owning task may have | |
1489 | * performed a setuid(), etc. | |
1490 | * | |
1491 | * Before the /proc/pid/status file was created the only way to read | |
1492 | * the effective uid of a /process was to stat /proc/pid. Reading | |
1493 | * /proc/pid/status is slow enough that procps and other packages | |
1494 | * kept stating /proc/pid. To keep the rules in /proc simple I have | |
1495 | * made this apply to all per process world readable and executable | |
1496 | * directories. | |
1497 | */ | |
1498 | static int pid_revalidate(struct dentry *dentry, struct nameidata *nd) | |
1499 | { | |
1500 | struct inode *inode = dentry->d_inode; | |
1501 | struct task_struct *task = get_proc_task(inode); | |
1502 | const struct cred *cred; | |
1503 | ||
1504 | if (task) { | |
1505 | if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) || | |
1506 | task_dumpable(task)) { | |
1507 | rcu_read_lock(); | |
1508 | cred = __task_cred(task); | |
1509 | inode->i_uid = cred->euid; | |
1510 | inode->i_gid = cred->egid; | |
1511 | rcu_read_unlock(); | |
1512 | } else { | |
1513 | inode->i_uid = 0; | |
1514 | inode->i_gid = 0; | |
1515 | } | |
1516 | inode->i_mode &= ~(S_ISUID | S_ISGID); | |
1517 | security_task_to_inode(task, inode); | |
1518 | put_task_struct(task); | |
1519 | return 1; | |
1520 | } | |
1521 | d_drop(dentry); | |
1522 | return 0; | |
1523 | } | |
1524 | ||
1525 | static int pid_delete_dentry(struct dentry * dentry) | |
1526 | { | |
1527 | /* Is the task we represent dead? | |
1528 | * If so, then don't put the dentry on the lru list, | |
1529 | * kill it immediately. | |
1530 | */ | |
1531 | return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first; | |
1532 | } | |
1533 | ||
1534 | static const struct dentry_operations pid_dentry_operations = | |
1535 | { | |
1536 | .d_revalidate = pid_revalidate, | |
1537 | .d_delete = pid_delete_dentry, | |
1538 | }; | |
1539 | ||
1540 | /* Lookups */ | |
1541 | ||
1542 | typedef struct dentry *instantiate_t(struct inode *, struct dentry *, | |
1543 | struct task_struct *, const void *); | |
1544 | ||
1545 | /* | |
1546 | * Fill a directory entry. | |
1547 | * | |
1548 | * If possible create the dcache entry and derive our inode number and | |
1549 | * file type from dcache entry. | |
1550 | * | |
1551 | * Since all of the proc inode numbers are dynamically generated, the inode | |
1552 | * numbers do not exist until the inode is cache. This means creating the | |
1553 | * the dcache entry in readdir is necessary to keep the inode numbers | |
1554 | * reported by readdir in sync with the inode numbers reported | |
1555 | * by stat. | |
1556 | */ | |
1557 | static int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir, | |
1558 | char *name, int len, | |
1559 | instantiate_t instantiate, struct task_struct *task, const void *ptr) | |
1560 | { | |
1561 | struct dentry *child, *dir = filp->f_path.dentry; | |
1562 | struct inode *inode; | |
1563 | struct qstr qname; | |
1564 | ino_t ino = 0; | |
1565 | unsigned type = DT_UNKNOWN; | |
1566 | ||
1567 | qname.name = name; | |
1568 | qname.len = len; | |
1569 | qname.hash = full_name_hash(name, len); | |
1570 | ||
1571 | child = d_lookup(dir, &qname); | |
1572 | if (!child) { | |
1573 | struct dentry *new; | |
1574 | new = d_alloc(dir, &qname); | |
1575 | if (new) { | |
1576 | child = instantiate(dir->d_inode, new, task, ptr); | |
1577 | if (child) | |
1578 | dput(new); | |
1579 | else | |
1580 | child = new; | |
1581 | } | |
1582 | } | |
1583 | if (!child || IS_ERR(child) || !child->d_inode) | |
1584 | goto end_instantiate; | |
1585 | inode = child->d_inode; | |
1586 | if (inode) { | |
1587 | ino = inode->i_ino; | |
1588 | type = inode->i_mode >> 12; | |
1589 | } | |
1590 | dput(child); | |
1591 | end_instantiate: | |
1592 | if (!ino) | |
1593 | ino = find_inode_number(dir, &qname); | |
1594 | if (!ino) | |
1595 | ino = 1; | |
1596 | return filldir(dirent, name, len, filp->f_pos, ino, type); | |
1597 | } | |
1598 | ||
1599 | static unsigned name_to_int(struct dentry *dentry) | |
1600 | { | |
1601 | const char *name = dentry->d_name.name; | |
1602 | int len = dentry->d_name.len; | |
1603 | unsigned n = 0; | |
1604 | ||
1605 | if (len > 1 && *name == '0') | |
1606 | goto out; | |
1607 | while (len-- > 0) { | |
1608 | unsigned c = *name++ - '0'; | |
1609 | if (c > 9) | |
1610 | goto out; | |
1611 | if (n >= (~0U-9)/10) | |
1612 | goto out; | |
1613 | n *= 10; | |
1614 | n += c; | |
1615 | } | |
1616 | return n; | |
1617 | out: | |
1618 | return ~0U; | |
1619 | } | |
1620 | ||
1621 | #define PROC_FDINFO_MAX 64 | |
1622 | ||
1623 | static int proc_fd_info(struct inode *inode, struct path *path, char *info) | |
1624 | { | |
1625 | struct task_struct *task = get_proc_task(inode); | |
1626 | struct files_struct *files = NULL; | |
1627 | struct file *file; | |
1628 | int fd = proc_fd(inode); | |
1629 | ||
1630 | if (task) { | |
1631 | files = get_files_struct(task); | |
1632 | put_task_struct(task); | |
1633 | } | |
1634 | if (files) { | |
1635 | /* | |
1636 | * We are not taking a ref to the file structure, so we must | |
1637 | * hold ->file_lock. | |
1638 | */ | |
1639 | spin_lock(&files->file_lock); | |
1640 | file = fcheck_files(files, fd); | |
1641 | if (file) { | |
1642 | if (path) { | |
1643 | *path = file->f_path; | |
1644 | path_get(&file->f_path); | |
1645 | } | |
1646 | if (info) | |
1647 | snprintf(info, PROC_FDINFO_MAX, | |
1648 | "pos:\t%lli\n" | |
1649 | "flags:\t0%o\n", | |
1650 | (long long) file->f_pos, | |
1651 | file->f_flags); | |
1652 | spin_unlock(&files->file_lock); | |
1653 | put_files_struct(files); | |
1654 | return 0; | |
1655 | } | |
1656 | spin_unlock(&files->file_lock); | |
1657 | put_files_struct(files); | |
1658 | } | |
1659 | return -ENOENT; | |
1660 | } | |
1661 | ||
1662 | static int proc_fd_link(struct inode *inode, struct path *path) | |
1663 | { | |
1664 | return proc_fd_info(inode, path, NULL); | |
1665 | } | |
1666 | ||
1667 | static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd) | |
1668 | { | |
1669 | struct inode *inode = dentry->d_inode; | |
1670 | struct task_struct *task = get_proc_task(inode); | |
1671 | int fd = proc_fd(inode); | |
1672 | struct files_struct *files; | |
1673 | const struct cred *cred; | |
1674 | ||
1675 | if (task) { | |
1676 | files = get_files_struct(task); | |
1677 | if (files) { | |
1678 | rcu_read_lock(); | |
1679 | if (fcheck_files(files, fd)) { | |
1680 | rcu_read_unlock(); | |
1681 | put_files_struct(files); | |
1682 | if (task_dumpable(task)) { | |
1683 | rcu_read_lock(); | |
1684 | cred = __task_cred(task); | |
1685 | inode->i_uid = cred->euid; | |
1686 | inode->i_gid = cred->egid; | |
1687 | rcu_read_unlock(); | |
1688 | } else { | |
1689 | inode->i_uid = 0; | |
1690 | inode->i_gid = 0; | |
1691 | } | |
1692 | inode->i_mode &= ~(S_ISUID | S_ISGID); | |
1693 | security_task_to_inode(task, inode); | |
1694 | put_task_struct(task); | |
1695 | return 1; | |
1696 | } | |
1697 | rcu_read_unlock(); | |
1698 | put_files_struct(files); | |
1699 | } | |
1700 | put_task_struct(task); | |
1701 | } | |
1702 | d_drop(dentry); | |
1703 | return 0; | |
1704 | } | |
1705 | ||
1706 | static const struct dentry_operations tid_fd_dentry_operations = | |
1707 | { | |
1708 | .d_revalidate = tid_fd_revalidate, | |
1709 | .d_delete = pid_delete_dentry, | |
1710 | }; | |
1711 | ||
1712 | static struct dentry *proc_fd_instantiate(struct inode *dir, | |
1713 | struct dentry *dentry, struct task_struct *task, const void *ptr) | |
1714 | { | |
1715 | unsigned fd = *(const unsigned *)ptr; | |
1716 | struct file *file; | |
1717 | struct files_struct *files; | |
1718 | struct inode *inode; | |
1719 | struct proc_inode *ei; | |
1720 | struct dentry *error = ERR_PTR(-ENOENT); | |
1721 | ||
1722 | inode = proc_pid_make_inode(dir->i_sb, task); | |
1723 | if (!inode) | |
1724 | goto out; | |
1725 | ei = PROC_I(inode); | |
1726 | ei->fd = fd; | |
1727 | files = get_files_struct(task); | |
1728 | if (!files) | |
1729 | goto out_iput; | |
1730 | inode->i_mode = S_IFLNK; | |
1731 | ||
1732 | /* | |
1733 | * We are not taking a ref to the file structure, so we must | |
1734 | * hold ->file_lock. | |
1735 | */ | |
1736 | spin_lock(&files->file_lock); | |
1737 | file = fcheck_files(files, fd); | |
1738 | if (!file) | |
1739 | goto out_unlock; | |
1740 | if (file->f_mode & FMODE_READ) | |
1741 | inode->i_mode |= S_IRUSR | S_IXUSR; | |
1742 | if (file->f_mode & FMODE_WRITE) | |
1743 | inode->i_mode |= S_IWUSR | S_IXUSR; | |
1744 | spin_unlock(&files->file_lock); | |
1745 | put_files_struct(files); | |
1746 | ||
1747 | inode->i_op = &proc_pid_link_inode_operations; | |
1748 | inode->i_size = 64; | |
1749 | ei->op.proc_get_link = proc_fd_link; | |
1750 | dentry->d_op = &tid_fd_dentry_operations; | |
1751 | d_add(dentry, inode); | |
1752 | /* Close the race of the process dying before we return the dentry */ | |
1753 | if (tid_fd_revalidate(dentry, NULL)) | |
1754 | error = NULL; | |
1755 | ||
1756 | out: | |
1757 | return error; | |
1758 | out_unlock: | |
1759 | spin_unlock(&files->file_lock); | |
1760 | put_files_struct(files); | |
1761 | out_iput: | |
1762 | iput(inode); | |
1763 | goto out; | |
1764 | } | |
1765 | ||
1766 | static struct dentry *proc_lookupfd_common(struct inode *dir, | |
1767 | struct dentry *dentry, | |
1768 | instantiate_t instantiate) | |
1769 | { | |
1770 | struct task_struct *task = get_proc_task(dir); | |
1771 | unsigned fd = name_to_int(dentry); | |
1772 | struct dentry *result = ERR_PTR(-ENOENT); | |
1773 | ||
1774 | if (!task) | |
1775 | goto out_no_task; | |
1776 | if (fd == ~0U) | |
1777 | goto out; | |
1778 | ||
1779 | result = instantiate(dir, dentry, task, &fd); | |
1780 | out: | |
1781 | put_task_struct(task); | |
1782 | out_no_task: | |
1783 | return result; | |
1784 | } | |
1785 | ||
1786 | static int proc_readfd_common(struct file * filp, void * dirent, | |
1787 | filldir_t filldir, instantiate_t instantiate) | |
1788 | { | |
1789 | struct dentry *dentry = filp->f_path.dentry; | |
1790 | struct inode *inode = dentry->d_inode; | |
1791 | struct task_struct *p = get_proc_task(inode); | |
1792 | unsigned int fd, ino; | |
1793 | int retval; | |
1794 | struct files_struct * files; | |
1795 | ||
1796 | retval = -ENOENT; | |
1797 | if (!p) | |
1798 | goto out_no_task; | |
1799 | retval = 0; | |
1800 | ||
1801 | fd = filp->f_pos; | |
1802 | switch (fd) { | |
1803 | case 0: | |
1804 | if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0) | |
1805 | goto out; | |
1806 | filp->f_pos++; | |
1807 | case 1: | |
1808 | ino = parent_ino(dentry); | |
1809 | if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0) | |
1810 | goto out; | |
1811 | filp->f_pos++; | |
1812 | default: | |
1813 | files = get_files_struct(p); | |
1814 | if (!files) | |
1815 | goto out; | |
1816 | rcu_read_lock(); | |
1817 | for (fd = filp->f_pos-2; | |
1818 | fd < files_fdtable(files)->max_fds; | |
1819 | fd++, filp->f_pos++) { | |
1820 | char name[PROC_NUMBUF]; | |
1821 | int len; | |
1822 | ||
1823 | if (!fcheck_files(files, fd)) | |
1824 | continue; | |
1825 | rcu_read_unlock(); | |
1826 | ||
1827 | len = snprintf(name, sizeof(name), "%d", fd); | |
1828 | if (proc_fill_cache(filp, dirent, filldir, | |
1829 | name, len, instantiate, | |
1830 | p, &fd) < 0) { | |
1831 | rcu_read_lock(); | |
1832 | break; | |
1833 | } | |
1834 | rcu_read_lock(); | |
1835 | } | |
1836 | rcu_read_unlock(); | |
1837 | put_files_struct(files); | |
1838 | } | |
1839 | out: | |
1840 | put_task_struct(p); | |
1841 | out_no_task: | |
1842 | return retval; | |
1843 | } | |
1844 | ||
1845 | static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry, | |
1846 | struct nameidata *nd) | |
1847 | { | |
1848 | return proc_lookupfd_common(dir, dentry, proc_fd_instantiate); | |
1849 | } | |
1850 | ||
1851 | static int proc_readfd(struct file *filp, void *dirent, filldir_t filldir) | |
1852 | { | |
1853 | return proc_readfd_common(filp, dirent, filldir, proc_fd_instantiate); | |
1854 | } | |
1855 | ||
1856 | static ssize_t proc_fdinfo_read(struct file *file, char __user *buf, | |
1857 | size_t len, loff_t *ppos) | |
1858 | { | |
1859 | char tmp[PROC_FDINFO_MAX]; | |
1860 | int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, tmp); | |
1861 | if (!err) | |
1862 | err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp)); | |
1863 | return err; | |
1864 | } | |
1865 | ||
1866 | static const struct file_operations proc_fdinfo_file_operations = { | |
1867 | .open = nonseekable_open, | |
1868 | .read = proc_fdinfo_read, | |
1869 | }; | |
1870 | ||
1871 | static const struct file_operations proc_fd_operations = { | |
1872 | .read = generic_read_dir, | |
1873 | .readdir = proc_readfd, | |
1874 | }; | |
1875 | ||
1876 | /* | |
1877 | * /proc/pid/fd needs a special permission handler so that a process can still | |
1878 | * access /proc/self/fd after it has executed a setuid(). | |
1879 | */ | |
1880 | static int proc_fd_permission(struct inode *inode, int mask) | |
1881 | { | |
1882 | int rv; | |
1883 | ||
1884 | rv = generic_permission(inode, mask, NULL); | |
1885 | if (rv == 0) | |
1886 | return 0; | |
1887 | if (task_pid(current) == proc_pid(inode)) | |
1888 | rv = 0; | |
1889 | return rv; | |
1890 | } | |
1891 | ||
1892 | /* | |
1893 | * proc directories can do almost nothing.. | |
1894 | */ | |
1895 | static const struct inode_operations proc_fd_inode_operations = { | |
1896 | .lookup = proc_lookupfd, | |
1897 | .permission = proc_fd_permission, | |
1898 | .setattr = proc_setattr, | |
1899 | }; | |
1900 | ||
1901 | static struct dentry *proc_fdinfo_instantiate(struct inode *dir, | |
1902 | struct dentry *dentry, struct task_struct *task, const void *ptr) | |
1903 | { | |
1904 | unsigned fd = *(unsigned *)ptr; | |
1905 | struct inode *inode; | |
1906 | struct proc_inode *ei; | |
1907 | struct dentry *error = ERR_PTR(-ENOENT); | |
1908 | ||
1909 | inode = proc_pid_make_inode(dir->i_sb, task); | |
1910 | if (!inode) | |
1911 | goto out; | |
1912 | ei = PROC_I(inode); | |
1913 | ei->fd = fd; | |
1914 | inode->i_mode = S_IFREG | S_IRUSR; | |
1915 | inode->i_fop = &proc_fdinfo_file_operations; | |
1916 | dentry->d_op = &tid_fd_dentry_operations; | |
1917 | d_add(dentry, inode); | |
1918 | /* Close the race of the process dying before we return the dentry */ | |
1919 | if (tid_fd_revalidate(dentry, NULL)) | |
1920 | error = NULL; | |
1921 | ||
1922 | out: | |
1923 | return error; | |
1924 | } | |
1925 | ||
1926 | static struct dentry *proc_lookupfdinfo(struct inode *dir, | |
1927 | struct dentry *dentry, | |
1928 | struct nameidata *nd) | |
1929 | { | |
1930 | return proc_lookupfd_common(dir, dentry, proc_fdinfo_instantiate); | |
1931 | } | |
1932 | ||
1933 | static int proc_readfdinfo(struct file *filp, void *dirent, filldir_t filldir) | |
1934 | { | |
1935 | return proc_readfd_common(filp, dirent, filldir, | |
1936 | proc_fdinfo_instantiate); | |
1937 | } | |
1938 | ||
1939 | static const struct file_operations proc_fdinfo_operations = { | |
1940 | .read = generic_read_dir, | |
1941 | .readdir = proc_readfdinfo, | |
1942 | }; | |
1943 | ||
1944 | /* | |
1945 | * proc directories can do almost nothing.. | |
1946 | */ | |
1947 | static const struct inode_operations proc_fdinfo_inode_operations = { | |
1948 | .lookup = proc_lookupfdinfo, | |
1949 | .setattr = proc_setattr, | |
1950 | }; | |
1951 | ||
1952 | ||
1953 | static struct dentry *proc_pident_instantiate(struct inode *dir, | |
1954 | struct dentry *dentry, struct task_struct *task, const void *ptr) | |
1955 | { | |
1956 | const struct pid_entry *p = ptr; | |
1957 | struct inode *inode; | |
1958 | struct proc_inode *ei; | |
1959 | struct dentry *error = ERR_PTR(-EINVAL); | |
1960 | ||
1961 | inode = proc_pid_make_inode(dir->i_sb, task); | |
1962 | if (!inode) | |
1963 | goto out; | |
1964 | ||
1965 | ei = PROC_I(inode); | |
1966 | inode->i_mode = p->mode; | |
1967 | if (S_ISDIR(inode->i_mode)) | |
1968 | inode->i_nlink = 2; /* Use getattr to fix if necessary */ | |
1969 | if (p->iop) | |
1970 | inode->i_op = p->iop; | |
1971 | if (p->fop) | |
1972 | inode->i_fop = p->fop; | |
1973 | ei->op = p->op; | |
1974 | dentry->d_op = &pid_dentry_operations; | |
1975 | d_add(dentry, inode); | |
1976 | /* Close the race of the process dying before we return the dentry */ | |
1977 | if (pid_revalidate(dentry, NULL)) | |
1978 | error = NULL; | |
1979 | out: | |
1980 | return error; | |
1981 | } | |
1982 | ||
1983 | static struct dentry *proc_pident_lookup(struct inode *dir, | |
1984 | struct dentry *dentry, | |
1985 | const struct pid_entry *ents, | |
1986 | unsigned int nents) | |
1987 | { | |
1988 | struct dentry *error; | |
1989 | struct task_struct *task = get_proc_task(dir); | |
1990 | const struct pid_entry *p, *last; | |
1991 | ||
1992 | error = ERR_PTR(-ENOENT); | |
1993 | ||
1994 | if (!task) | |
1995 | goto out_no_task; | |
1996 | ||
1997 | /* | |
1998 | * Yes, it does not scale. And it should not. Don't add | |
1999 | * new entries into /proc/<tgid>/ without very good reasons. | |
2000 | */ | |
2001 | last = &ents[nents - 1]; | |
2002 | for (p = ents; p <= last; p++) { | |
2003 | if (p->len != dentry->d_name.len) | |
2004 | continue; | |
2005 | if (!memcmp(dentry->d_name.name, p->name, p->len)) | |
2006 | break; | |
2007 | } | |
2008 | if (p > last) | |
2009 | goto out; | |
2010 | ||
2011 | error = proc_pident_instantiate(dir, dentry, task, p); | |
2012 | out: | |
2013 | put_task_struct(task); | |
2014 | out_no_task: | |
2015 | return error; | |
2016 | } | |
2017 | ||
2018 | static int proc_pident_fill_cache(struct file *filp, void *dirent, | |
2019 | filldir_t filldir, struct task_struct *task, const struct pid_entry *p) | |
2020 | { | |
2021 | return proc_fill_cache(filp, dirent, filldir, p->name, p->len, | |
2022 | proc_pident_instantiate, task, p); | |
2023 | } | |
2024 | ||
2025 | static int proc_pident_readdir(struct file *filp, | |
2026 | void *dirent, filldir_t filldir, | |
2027 | const struct pid_entry *ents, unsigned int nents) | |
2028 | { | |
2029 | int i; | |
2030 | struct dentry *dentry = filp->f_path.dentry; | |
2031 | struct inode *inode = dentry->d_inode; | |
2032 | struct task_struct *task = get_proc_task(inode); | |
2033 | const struct pid_entry *p, *last; | |
2034 | ino_t ino; | |
2035 | int ret; | |
2036 | ||
2037 | ret = -ENOENT; | |
2038 | if (!task) | |
2039 | goto out_no_task; | |
2040 | ||
2041 | ret = 0; | |
2042 | i = filp->f_pos; | |
2043 | switch (i) { | |
2044 | case 0: | |
2045 | ino = inode->i_ino; | |
2046 | if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) | |
2047 | goto out; | |
2048 | i++; | |
2049 | filp->f_pos++; | |
2050 | /* fall through */ | |
2051 | case 1: | |
2052 | ino = parent_ino(dentry); | |
2053 | if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0) | |
2054 | goto out; | |
2055 | i++; | |
2056 | filp->f_pos++; | |
2057 | /* fall through */ | |
2058 | default: | |
2059 | i -= 2; | |
2060 | if (i >= nents) { | |
2061 | ret = 1; | |
2062 | goto out; | |
2063 | } | |
2064 | p = ents + i; | |
2065 | last = &ents[nents - 1]; | |
2066 | while (p <= last) { | |
2067 | if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0) | |
2068 | goto out; | |
2069 | filp->f_pos++; | |
2070 | p++; | |
2071 | } | |
2072 | } | |
2073 | ||
2074 | ret = 1; | |
2075 | out: | |
2076 | put_task_struct(task); | |
2077 | out_no_task: | |
2078 | return ret; | |
2079 | } | |
2080 | ||
2081 | #ifdef CONFIG_SECURITY | |
2082 | static ssize_t proc_pid_attr_read(struct file * file, char __user * buf, | |
2083 | size_t count, loff_t *ppos) | |
2084 | { | |
2085 | struct inode * inode = file->f_path.dentry->d_inode; | |
2086 | char *p = NULL; | |
2087 | ssize_t length; | |
2088 | struct task_struct *task = get_proc_task(inode); | |
2089 | ||
2090 | if (!task) | |
2091 | return -ESRCH; | |
2092 | ||
2093 | length = security_getprocattr(task, | |
2094 | (char*)file->f_path.dentry->d_name.name, | |
2095 | &p); | |
2096 | put_task_struct(task); | |
2097 | if (length > 0) | |
2098 | length = simple_read_from_buffer(buf, count, ppos, p, length); | |
2099 | kfree(p); | |
2100 | return length; | |
2101 | } | |
2102 | ||
2103 | static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, | |
2104 | size_t count, loff_t *ppos) | |
2105 | { | |
2106 | struct inode * inode = file->f_path.dentry->d_inode; | |
2107 | char *page; | |
2108 | ssize_t length; | |
2109 | struct task_struct *task = get_proc_task(inode); | |
2110 | ||
2111 | length = -ESRCH; | |
2112 | if (!task) | |
2113 | goto out_no_task; | |
2114 | if (count > PAGE_SIZE) | |
2115 | count = PAGE_SIZE; | |
2116 | ||
2117 | /* No partial writes. */ | |
2118 | length = -EINVAL; | |
2119 | if (*ppos != 0) | |
2120 | goto out; | |
2121 | ||
2122 | length = -ENOMEM; | |
2123 | page = (char*)__get_free_page(GFP_TEMPORARY); | |
2124 | if (!page) | |
2125 | goto out; | |
2126 | ||
2127 | length = -EFAULT; | |
2128 | if (copy_from_user(page, buf, count)) | |
2129 | goto out_free; | |
2130 | ||
2131 | length = security_setprocattr(task, | |
2132 | (char*)file->f_path.dentry->d_name.name, | |
2133 | (void*)page, count); | |
2134 | out_free: | |
2135 | free_page((unsigned long) page); | |
2136 | out: | |
2137 | put_task_struct(task); | |
2138 | out_no_task: | |
2139 | return length; | |
2140 | } | |
2141 | ||
2142 | static const struct file_operations proc_pid_attr_operations = { | |
2143 | .read = proc_pid_attr_read, | |
2144 | .write = proc_pid_attr_write, | |
2145 | }; | |
2146 | ||
2147 | static const struct pid_entry attr_dir_stuff[] = { | |
2148 | REG("current", S_IRUGO|S_IWUGO, proc_pid_attr_operations), | |
2149 | REG("prev", S_IRUGO, proc_pid_attr_operations), | |
2150 | REG("exec", S_IRUGO|S_IWUGO, proc_pid_attr_operations), | |
2151 | REG("fscreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), | |
2152 | REG("keycreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), | |
2153 | REG("sockcreate", S_IRUGO|S_IWUGO, proc_pid_attr_operations), | |
2154 | }; | |
2155 | ||
2156 | static int proc_attr_dir_readdir(struct file * filp, | |
2157 | void * dirent, filldir_t filldir) | |
2158 | { | |
2159 | return proc_pident_readdir(filp,dirent,filldir, | |
2160 | attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff)); | |
2161 | } | |
2162 | ||
2163 | static const struct file_operations proc_attr_dir_operations = { | |
2164 | .read = generic_read_dir, | |
2165 | .readdir = proc_attr_dir_readdir, | |
2166 | }; | |
2167 | ||
2168 | static struct dentry *proc_attr_dir_lookup(struct inode *dir, | |
2169 | struct dentry *dentry, struct nameidata *nd) | |
2170 | { | |
2171 | return proc_pident_lookup(dir, dentry, | |
2172 | attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff)); | |
2173 | } | |
2174 | ||
2175 | static const struct inode_operations proc_attr_dir_inode_operations = { | |
2176 | .lookup = proc_attr_dir_lookup, | |
2177 | .getattr = pid_getattr, | |
2178 | .setattr = proc_setattr, | |
2179 | }; | |
2180 | ||
2181 | #endif | |
2182 | ||
2183 | #if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE) | |
2184 | static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf, | |
2185 | size_t count, loff_t *ppos) | |
2186 | { | |
2187 | struct task_struct *task = get_proc_task(file->f_dentry->d_inode); | |
2188 | struct mm_struct *mm; | |
2189 | char buffer[PROC_NUMBUF]; | |
2190 | size_t len; | |
2191 | int ret; | |
2192 | ||
2193 | if (!task) | |
2194 | return -ESRCH; | |
2195 | ||
2196 | ret = 0; | |
2197 | mm = get_task_mm(task); | |
2198 | if (mm) { | |
2199 | len = snprintf(buffer, sizeof(buffer), "%08lx\n", | |
2200 | ((mm->flags & MMF_DUMP_FILTER_MASK) >> | |
2201 | MMF_DUMP_FILTER_SHIFT)); | |
2202 | mmput(mm); | |
2203 | ret = simple_read_from_buffer(buf, count, ppos, buffer, len); | |
2204 | } | |
2205 | ||
2206 | put_task_struct(task); | |
2207 | ||
2208 | return ret; | |
2209 | } | |
2210 | ||
2211 | static ssize_t proc_coredump_filter_write(struct file *file, | |
2212 | const char __user *buf, | |
2213 | size_t count, | |
2214 | loff_t *ppos) | |
2215 | { | |
2216 | struct task_struct *task; | |
2217 | struct mm_struct *mm; | |
2218 | char buffer[PROC_NUMBUF], *end; | |
2219 | unsigned int val; | |
2220 | int ret; | |
2221 | int i; | |
2222 | unsigned long mask; | |
2223 | ||
2224 | ret = -EFAULT; | |
2225 | memset(buffer, 0, sizeof(buffer)); | |
2226 | if (count > sizeof(buffer) - 1) | |
2227 | count = sizeof(buffer) - 1; | |
2228 | if (copy_from_user(buffer, buf, count)) | |
2229 | goto out_no_task; | |
2230 | ||
2231 | ret = -EINVAL; | |
2232 | val = (unsigned int)simple_strtoul(buffer, &end, 0); | |
2233 | if (*end == '\n') | |
2234 | end++; | |
2235 | if (end - buffer == 0) | |
2236 | goto out_no_task; | |
2237 | ||
2238 | ret = -ESRCH; | |
2239 | task = get_proc_task(file->f_dentry->d_inode); | |
2240 | if (!task) | |
2241 | goto out_no_task; | |
2242 | ||
2243 | ret = end - buffer; | |
2244 | mm = get_task_mm(task); | |
2245 | if (!mm) | |
2246 | goto out_no_mm; | |
2247 | ||
2248 | for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) { | |
2249 | if (val & mask) | |
2250 | set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); | |
2251 | else | |
2252 | clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags); | |
2253 | } | |
2254 | ||
2255 | mmput(mm); | |
2256 | out_no_mm: | |
2257 | put_task_struct(task); | |
2258 | out_no_task: | |
2259 | return ret; | |
2260 | } | |
2261 | ||
2262 | static const struct file_operations proc_coredump_filter_operations = { | |
2263 | .read = proc_coredump_filter_read, | |
2264 | .write = proc_coredump_filter_write, | |
2265 | }; | |
2266 | #endif | |
2267 | ||
2268 | /* | |
2269 | * /proc/self: | |
2270 | */ | |
2271 | static int proc_self_readlink(struct dentry *dentry, char __user *buffer, | |
2272 | int buflen) | |
2273 | { | |
2274 | struct pid_namespace *ns = dentry->d_sb->s_fs_info; | |
2275 | pid_t tgid = task_tgid_nr_ns(current, ns); | |
2276 | char tmp[PROC_NUMBUF]; | |
2277 | if (!tgid) | |
2278 | return -ENOENT; | |
2279 | sprintf(tmp, "%d", tgid); | |
2280 | return vfs_readlink(dentry,buffer,buflen,tmp); | |
2281 | } | |
2282 | ||
2283 | static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd) | |
2284 | { | |
2285 | struct pid_namespace *ns = dentry->d_sb->s_fs_info; | |
2286 | pid_t tgid = task_tgid_nr_ns(current, ns); | |
2287 | char tmp[PROC_NUMBUF]; | |
2288 | if (!tgid) | |
2289 | return ERR_PTR(-ENOENT); | |
2290 | sprintf(tmp, "%d", task_tgid_nr_ns(current, ns)); | |
2291 | return ERR_PTR(vfs_follow_link(nd,tmp)); | |
2292 | } | |
2293 | ||
2294 | static const struct inode_operations proc_self_inode_operations = { | |
2295 | .readlink = proc_self_readlink, | |
2296 | .follow_link = proc_self_follow_link, | |
2297 | }; | |
2298 | ||
2299 | /* | |
2300 | * proc base | |
2301 | * | |
2302 | * These are the directory entries in the root directory of /proc | |
2303 | * that properly belong to the /proc filesystem, as they describe | |
2304 | * describe something that is process related. | |
2305 | */ | |
2306 | static const struct pid_entry proc_base_stuff[] = { | |
2307 | NOD("self", S_IFLNK|S_IRWXUGO, | |
2308 | &proc_self_inode_operations, NULL, {}), | |
2309 | }; | |
2310 | ||
2311 | /* | |
2312 | * Exceptional case: normally we are not allowed to unhash a busy | |
2313 | * directory. In this case, however, we can do it - no aliasing problems | |
2314 | * due to the way we treat inodes. | |
2315 | */ | |
2316 | static int proc_base_revalidate(struct dentry *dentry, struct nameidata *nd) | |
2317 | { | |
2318 | struct inode *inode = dentry->d_inode; | |
2319 | struct task_struct *task = get_proc_task(inode); | |
2320 | if (task) { | |
2321 | put_task_struct(task); | |
2322 | return 1; | |
2323 | } | |
2324 | d_drop(dentry); | |
2325 | return 0; | |
2326 | } | |
2327 | ||
2328 | static const struct dentry_operations proc_base_dentry_operations = | |
2329 | { | |
2330 | .d_revalidate = proc_base_revalidate, | |
2331 | .d_delete = pid_delete_dentry, | |
2332 | }; | |
2333 | ||
2334 | static struct dentry *proc_base_instantiate(struct inode *dir, | |
2335 | struct dentry *dentry, struct task_struct *task, const void *ptr) | |
2336 | { | |
2337 | const struct pid_entry *p = ptr; | |
2338 | struct inode *inode; | |
2339 | struct proc_inode *ei; | |
2340 | struct dentry *error = ERR_PTR(-EINVAL); | |
2341 | ||
2342 | /* Allocate the inode */ | |
2343 | error = ERR_PTR(-ENOMEM); | |
2344 | inode = new_inode(dir->i_sb); | |
2345 | if (!inode) | |
2346 | goto out; | |
2347 | ||
2348 | /* Initialize the inode */ | |
2349 | ei = PROC_I(inode); | |
2350 | inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; | |
2351 | ||
2352 | /* | |
2353 | * grab the reference to the task. | |
2354 | */ | |
2355 | ei->pid = get_task_pid(task, PIDTYPE_PID); | |
2356 | if (!ei->pid) | |
2357 | goto out_iput; | |
2358 | ||
2359 | inode->i_mode = p->mode; | |
2360 | if (S_ISDIR(inode->i_mode)) | |
2361 | inode->i_nlink = 2; | |
2362 | if (S_ISLNK(inode->i_mode)) | |
2363 | inode->i_size = 64; | |
2364 | if (p->iop) | |
2365 | inode->i_op = p->iop; | |
2366 | if (p->fop) | |
2367 | inode->i_fop = p->fop; | |
2368 | ei->op = p->op; | |
2369 | dentry->d_op = &proc_base_dentry_operations; | |
2370 | d_add(dentry, inode); | |
2371 | error = NULL; | |
2372 | out: | |
2373 | return error; | |
2374 | out_iput: | |
2375 | iput(inode); | |
2376 | goto out; | |
2377 | } | |
2378 | ||
2379 | static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry) | |
2380 | { | |
2381 | struct dentry *error; | |
2382 | struct task_struct *task = get_proc_task(dir); | |
2383 | const struct pid_entry *p, *last; | |
2384 | ||
2385 | error = ERR_PTR(-ENOENT); | |
2386 | ||
2387 | if (!task) | |
2388 | goto out_no_task; | |
2389 | ||
2390 | /* Lookup the directory entry */ | |
2391 | last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1]; | |
2392 | for (p = proc_base_stuff; p <= last; p++) { | |
2393 | if (p->len != dentry->d_name.len) | |
2394 | continue; | |
2395 | if (!memcmp(dentry->d_name.name, p->name, p->len)) | |
2396 | break; | |
2397 | } | |
2398 | if (p > last) | |
2399 | goto out; | |
2400 | ||
2401 | error = proc_base_instantiate(dir, dentry, task, p); | |
2402 | ||
2403 | out: | |
2404 | put_task_struct(task); | |
2405 | out_no_task: | |
2406 | return error; | |
2407 | } | |
2408 | ||
2409 | static int proc_base_fill_cache(struct file *filp, void *dirent, | |
2410 | filldir_t filldir, struct task_struct *task, const struct pid_entry *p) | |
2411 | { | |
2412 | return proc_fill_cache(filp, dirent, filldir, p->name, p->len, | |
2413 | proc_base_instantiate, task, p); | |
2414 | } | |
2415 | ||
2416 | #ifdef CONFIG_TASK_IO_ACCOUNTING | |
2417 | static int do_io_accounting(struct task_struct *task, char *buffer, int whole) | |
2418 | { | |
2419 | struct task_io_accounting acct = task->ioac; | |
2420 | unsigned long flags; | |
2421 | ||
2422 | if (whole && lock_task_sighand(task, &flags)) { | |
2423 | struct task_struct *t = task; | |
2424 | ||
2425 | task_io_accounting_add(&acct, &task->signal->ioac); | |
2426 | while_each_thread(task, t) | |
2427 | task_io_accounting_add(&acct, &t->ioac); | |
2428 | ||
2429 | unlock_task_sighand(task, &flags); | |
2430 | } | |
2431 | return sprintf(buffer, | |
2432 | "rchar: %llu\n" | |
2433 | "wchar: %llu\n" | |
2434 | "syscr: %llu\n" | |
2435 | "syscw: %llu\n" | |
2436 | "read_bytes: %llu\n" | |
2437 | "write_bytes: %llu\n" | |
2438 | "cancelled_write_bytes: %llu\n", | |
2439 | (unsigned long long)acct.rchar, | |
2440 | (unsigned long long)acct.wchar, | |
2441 | (unsigned long long)acct.syscr, | |
2442 | (unsigned long long)acct.syscw, | |
2443 | (unsigned long long)acct.read_bytes, | |
2444 | (unsigned long long)acct.write_bytes, | |
2445 | (unsigned long long)acct.cancelled_write_bytes); | |
2446 | } | |
2447 | ||
2448 | static int proc_tid_io_accounting(struct task_struct *task, char *buffer) | |
2449 | { | |
2450 | return do_io_accounting(task, buffer, 0); | |
2451 | } | |
2452 | ||
2453 | static int proc_tgid_io_accounting(struct task_struct *task, char *buffer) | |
2454 | { | |
2455 | return do_io_accounting(task, buffer, 1); | |
2456 | } | |
2457 | #endif /* CONFIG_TASK_IO_ACCOUNTING */ | |
2458 | ||
2459 | static int proc_pid_personality(struct seq_file *m, struct pid_namespace *ns, | |
2460 | struct pid *pid, struct task_struct *task) | |
2461 | { | |
2462 | seq_printf(m, "%08x\n", task->personality); | |
2463 | return 0; | |
2464 | } | |
2465 | ||
2466 | /* | |
2467 | * Thread groups | |
2468 | */ | |
2469 | static const struct file_operations proc_task_operations; | |
2470 | static const struct inode_operations proc_task_inode_operations; | |
2471 | ||
2472 | static const struct pid_entry tgid_base_stuff[] = { | |
2473 | DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations), | |
2474 | DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), | |
2475 | DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations), | |
2476 | #ifdef CONFIG_NET | |
2477 | DIR("net", S_IRUGO|S_IXUGO, proc_net_inode_operations, proc_net_operations), | |
2478 | #endif | |
2479 | REG("environ", S_IRUSR, proc_environ_operations), | |
2480 | INF("auxv", S_IRUSR, proc_pid_auxv), | |
2481 | ONE("status", S_IRUGO, proc_pid_status), | |
2482 | ONE("personality", S_IRUSR, proc_pid_personality), | |
2483 | INF("limits", S_IRUSR, proc_pid_limits), | |
2484 | #ifdef CONFIG_SCHED_DEBUG | |
2485 | REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), | |
2486 | #endif | |
2487 | #ifdef CONFIG_HAVE_ARCH_TRACEHOOK | |
2488 | INF("syscall", S_IRUSR, proc_pid_syscall), | |
2489 | #endif | |
2490 | INF("cmdline", S_IRUGO, proc_pid_cmdline), | |
2491 | ONE("stat", S_IRUGO, proc_tgid_stat), | |
2492 | ONE("statm", S_IRUGO, proc_pid_statm), | |
2493 | REG("maps", S_IRUGO, proc_maps_operations), | |
2494 | #ifdef CONFIG_NUMA | |
2495 | REG("numa_maps", S_IRUGO, proc_numa_maps_operations), | |
2496 | #endif | |
2497 | REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), | |
2498 | LNK("cwd", proc_cwd_link), | |
2499 | LNK("root", proc_root_link), | |
2500 | LNK("exe", proc_exe_link), | |
2501 | REG("mounts", S_IRUGO, proc_mounts_operations), | |
2502 | REG("mountinfo", S_IRUGO, proc_mountinfo_operations), | |
2503 | REG("mountstats", S_IRUSR, proc_mountstats_operations), | |
2504 | #ifdef CONFIG_PROC_PAGE_MONITOR | |
2505 | REG("clear_refs", S_IWUSR, proc_clear_refs_operations), | |
2506 | REG("smaps", S_IRUGO, proc_smaps_operations), | |
2507 | REG("pagemap", S_IRUSR, proc_pagemap_operations), | |
2508 | #endif | |
2509 | #ifdef CONFIG_SECURITY | |
2510 | DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), | |
2511 | #endif | |
2512 | #ifdef CONFIG_KALLSYMS | |
2513 | INF("wchan", S_IRUGO, proc_pid_wchan), | |
2514 | #endif | |
2515 | #ifdef CONFIG_STACKTRACE | |
2516 | ONE("stack", S_IRUSR, proc_pid_stack), | |
2517 | #endif | |
2518 | #ifdef CONFIG_SCHEDSTATS | |
2519 | INF("schedstat", S_IRUGO, proc_pid_schedstat), | |
2520 | #endif | |
2521 | #ifdef CONFIG_LATENCYTOP | |
2522 | REG("latency", S_IRUGO, proc_lstats_operations), | |
2523 | #endif | |
2524 | #ifdef CONFIG_PROC_PID_CPUSET | |
2525 | REG("cpuset", S_IRUGO, proc_cpuset_operations), | |
2526 | #endif | |
2527 | #ifdef CONFIG_CGROUPS | |
2528 | REG("cgroup", S_IRUGO, proc_cgroup_operations), | |
2529 | #endif | |
2530 | INF("oom_score", S_IRUGO, proc_oom_score), | |
2531 | REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations), | |
2532 | #ifdef CONFIG_AUDITSYSCALL | |
2533 | REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), | |
2534 | REG("sessionid", S_IRUGO, proc_sessionid_operations), | |
2535 | #endif | |
2536 | #ifdef CONFIG_FAULT_INJECTION | |
2537 | REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), | |
2538 | #endif | |
2539 | #if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE) | |
2540 | REG("coredump_filter", S_IRUGO|S_IWUSR, proc_coredump_filter_operations), | |
2541 | #endif | |
2542 | #ifdef CONFIG_TASK_IO_ACCOUNTING | |
2543 | INF("io", S_IRUGO, proc_tgid_io_accounting), | |
2544 | #endif | |
2545 | }; | |
2546 | ||
2547 | static int proc_tgid_base_readdir(struct file * filp, | |
2548 | void * dirent, filldir_t filldir) | |
2549 | { | |
2550 | return proc_pident_readdir(filp,dirent,filldir, | |
2551 | tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff)); | |
2552 | } | |
2553 | ||
2554 | static const struct file_operations proc_tgid_base_operations = { | |
2555 | .read = generic_read_dir, | |
2556 | .readdir = proc_tgid_base_readdir, | |
2557 | }; | |
2558 | ||
2559 | static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ | |
2560 | return proc_pident_lookup(dir, dentry, | |
2561 | tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff)); | |
2562 | } | |
2563 | ||
2564 | static const struct inode_operations proc_tgid_base_inode_operations = { | |
2565 | .lookup = proc_tgid_base_lookup, | |
2566 | .getattr = pid_getattr, | |
2567 | .setattr = proc_setattr, | |
2568 | }; | |
2569 | ||
2570 | static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid) | |
2571 | { | |
2572 | struct dentry *dentry, *leader, *dir; | |
2573 | char buf[PROC_NUMBUF]; | |
2574 | struct qstr name; | |
2575 | ||
2576 | name.name = buf; | |
2577 | name.len = snprintf(buf, sizeof(buf), "%d", pid); | |
2578 | dentry = d_hash_and_lookup(mnt->mnt_root, &name); | |
2579 | if (dentry) { | |
2580 | if (!(current->flags & PF_EXITING)) | |
2581 | shrink_dcache_parent(dentry); | |
2582 | d_drop(dentry); | |
2583 | dput(dentry); | |
2584 | } | |
2585 | ||
2586 | if (tgid == 0) | |
2587 | goto out; | |
2588 | ||
2589 | name.name = buf; | |
2590 | name.len = snprintf(buf, sizeof(buf), "%d", tgid); | |
2591 | leader = d_hash_and_lookup(mnt->mnt_root, &name); | |
2592 | if (!leader) | |
2593 | goto out; | |
2594 | ||
2595 | name.name = "task"; | |
2596 | name.len = strlen(name.name); | |
2597 | dir = d_hash_and_lookup(leader, &name); | |
2598 | if (!dir) | |
2599 | goto out_put_leader; | |
2600 | ||
2601 | name.name = buf; | |
2602 | name.len = snprintf(buf, sizeof(buf), "%d", pid); | |
2603 | dentry = d_hash_and_lookup(dir, &name); | |
2604 | if (dentry) { | |
2605 | shrink_dcache_parent(dentry); | |
2606 | d_drop(dentry); | |
2607 | dput(dentry); | |
2608 | } | |
2609 | ||
2610 | dput(dir); | |
2611 | out_put_leader: | |
2612 | dput(leader); | |
2613 | out: | |
2614 | return; | |
2615 | } | |
2616 | ||
2617 | /** | |
2618 | * proc_flush_task - Remove dcache entries for @task from the /proc dcache. | |
2619 | * @task: task that should be flushed. | |
2620 | * | |
2621 | * When flushing dentries from proc, one needs to flush them from global | |
2622 | * proc (proc_mnt) and from all the namespaces' procs this task was seen | |
2623 | * in. This call is supposed to do all of this job. | |
2624 | * | |
2625 | * Looks in the dcache for | |
2626 | * /proc/@pid | |
2627 | * /proc/@tgid/task/@pid | |
2628 | * if either directory is present flushes it and all of it'ts children | |
2629 | * from the dcache. | |
2630 | * | |
2631 | * It is safe and reasonable to cache /proc entries for a task until | |
2632 | * that task exits. After that they just clog up the dcache with | |
2633 | * useless entries, possibly causing useful dcache entries to be | |
2634 | * flushed instead. This routine is proved to flush those useless | |
2635 | * dcache entries at process exit time. | |
2636 | * | |
2637 | * NOTE: This routine is just an optimization so it does not guarantee | |
2638 | * that no dcache entries will exist at process exit time it | |
2639 | * just makes it very unlikely that any will persist. | |
2640 | */ | |
2641 | ||
2642 | void proc_flush_task(struct task_struct *task) | |
2643 | { | |
2644 | int i; | |
2645 | struct pid *pid, *tgid = NULL; | |
2646 | struct upid *upid; | |
2647 | ||
2648 | pid = task_pid(task); | |
2649 | if (thread_group_leader(task)) | |
2650 | tgid = task_tgid(task); | |
2651 | ||
2652 | for (i = 0; i <= pid->level; i++) { | |
2653 | upid = &pid->numbers[i]; | |
2654 | proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr, | |
2655 | tgid ? tgid->numbers[i].nr : 0); | |
2656 | } | |
2657 | ||
2658 | upid = &pid->numbers[pid->level]; | |
2659 | if (upid->nr == 1) | |
2660 | pid_ns_release_proc(upid->ns); | |
2661 | } | |
2662 | ||
2663 | static struct dentry *proc_pid_instantiate(struct inode *dir, | |
2664 | struct dentry * dentry, | |
2665 | struct task_struct *task, const void *ptr) | |
2666 | { | |
2667 | struct dentry *error = ERR_PTR(-ENOENT); | |
2668 | struct inode *inode; | |
2669 | ||
2670 | inode = proc_pid_make_inode(dir->i_sb, task); | |
2671 | if (!inode) | |
2672 | goto out; | |
2673 | ||
2674 | inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; | |
2675 | inode->i_op = &proc_tgid_base_inode_operations; | |
2676 | inode->i_fop = &proc_tgid_base_operations; | |
2677 | inode->i_flags|=S_IMMUTABLE; | |
2678 | ||
2679 | inode->i_nlink = 2 + pid_entry_count_dirs(tgid_base_stuff, | |
2680 | ARRAY_SIZE(tgid_base_stuff)); | |
2681 | ||
2682 | dentry->d_op = &pid_dentry_operations; | |
2683 | ||
2684 | d_add(dentry, inode); | |
2685 | /* Close the race of the process dying before we return the dentry */ | |
2686 | if (pid_revalidate(dentry, NULL)) | |
2687 | error = NULL; | |
2688 | out: | |
2689 | return error; | |
2690 | } | |
2691 | ||
2692 | struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) | |
2693 | { | |
2694 | struct dentry *result = ERR_PTR(-ENOENT); | |
2695 | struct task_struct *task; | |
2696 | unsigned tgid; | |
2697 | struct pid_namespace *ns; | |
2698 | ||
2699 | result = proc_base_lookup(dir, dentry); | |
2700 | if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT) | |
2701 | goto out; | |
2702 | ||
2703 | tgid = name_to_int(dentry); | |
2704 | if (tgid == ~0U) | |
2705 | goto out; | |
2706 | ||
2707 | ns = dentry->d_sb->s_fs_info; | |
2708 | rcu_read_lock(); | |
2709 | task = find_task_by_pid_ns(tgid, ns); | |
2710 | if (task) | |
2711 | get_task_struct(task); | |
2712 | rcu_read_unlock(); | |
2713 | if (!task) | |
2714 | goto out; | |
2715 | ||
2716 | result = proc_pid_instantiate(dir, dentry, task, NULL); | |
2717 | put_task_struct(task); | |
2718 | out: | |
2719 | return result; | |
2720 | } | |
2721 | ||
2722 | /* | |
2723 | * Find the first task with tgid >= tgid | |
2724 | * | |
2725 | */ | |
2726 | struct tgid_iter { | |
2727 | unsigned int tgid; | |
2728 | struct task_struct *task; | |
2729 | }; | |
2730 | static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter) | |
2731 | { | |
2732 | struct pid *pid; | |
2733 | ||
2734 | if (iter.task) | |
2735 | put_task_struct(iter.task); | |
2736 | rcu_read_lock(); | |
2737 | retry: | |
2738 | iter.task = NULL; | |
2739 | pid = find_ge_pid(iter.tgid, ns); | |
2740 | if (pid) { | |
2741 | iter.tgid = pid_nr_ns(pid, ns); | |
2742 | iter.task = pid_task(pid, PIDTYPE_PID); | |
2743 | /* What we to know is if the pid we have find is the | |
2744 | * pid of a thread_group_leader. Testing for task | |
2745 | * being a thread_group_leader is the obvious thing | |
2746 | * todo but there is a window when it fails, due to | |
2747 | * the pid transfer logic in de_thread. | |
2748 | * | |
2749 | * So we perform the straight forward test of seeing | |
2750 | * if the pid we have found is the pid of a thread | |
2751 | * group leader, and don't worry if the task we have | |
2752 | * found doesn't happen to be a thread group leader. | |
2753 | * As we don't care in the case of readdir. | |
2754 | */ | |
2755 | if (!iter.task || !has_group_leader_pid(iter.task)) { | |
2756 | iter.tgid += 1; | |
2757 | goto retry; | |
2758 | } | |
2759 | get_task_struct(iter.task); | |
2760 | } | |
2761 | rcu_read_unlock(); | |
2762 | return iter; | |
2763 | } | |
2764 | ||
2765 | #define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff)) | |
2766 | ||
2767 | static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir, | |
2768 | struct tgid_iter iter) | |
2769 | { | |
2770 | char name[PROC_NUMBUF]; | |
2771 | int len = snprintf(name, sizeof(name), "%d", iter.tgid); | |
2772 | return proc_fill_cache(filp, dirent, filldir, name, len, | |
2773 | proc_pid_instantiate, iter.task, NULL); | |
2774 | } | |
2775 | ||
2776 | /* for the /proc/ directory itself, after non-process stuff has been done */ | |
2777 | int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir) | |
2778 | { | |
2779 | unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY; | |
2780 | struct task_struct *reaper = get_proc_task(filp->f_path.dentry->d_inode); | |
2781 | struct tgid_iter iter; | |
2782 | struct pid_namespace *ns; | |
2783 | ||
2784 | if (!reaper) | |
2785 | goto out_no_task; | |
2786 | ||
2787 | for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) { | |
2788 | const struct pid_entry *p = &proc_base_stuff[nr]; | |
2789 | if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0) | |
2790 | goto out; | |
2791 | } | |
2792 | ||
2793 | ns = filp->f_dentry->d_sb->s_fs_info; | |
2794 | iter.task = NULL; | |
2795 | iter.tgid = filp->f_pos - TGID_OFFSET; | |
2796 | for (iter = next_tgid(ns, iter); | |
2797 | iter.task; | |
2798 | iter.tgid += 1, iter = next_tgid(ns, iter)) { | |
2799 | filp->f_pos = iter.tgid + TGID_OFFSET; | |
2800 | if (proc_pid_fill_cache(filp, dirent, filldir, iter) < 0) { | |
2801 | put_task_struct(iter.task); | |
2802 | goto out; | |
2803 | } | |
2804 | } | |
2805 | filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET; | |
2806 | out: | |
2807 | put_task_struct(reaper); | |
2808 | out_no_task: | |
2809 | return 0; | |
2810 | } | |
2811 | ||
2812 | /* | |
2813 | * Tasks | |
2814 | */ | |
2815 | static const struct pid_entry tid_base_stuff[] = { | |
2816 | DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations), | |
2817 | DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fd_operations), | |
2818 | REG("environ", S_IRUSR, proc_environ_operations), | |
2819 | INF("auxv", S_IRUSR, proc_pid_auxv), | |
2820 | ONE("status", S_IRUGO, proc_pid_status), | |
2821 | ONE("personality", S_IRUSR, proc_pid_personality), | |
2822 | INF("limits", S_IRUSR, proc_pid_limits), | |
2823 | #ifdef CONFIG_SCHED_DEBUG | |
2824 | REG("sched", S_IRUGO|S_IWUSR, proc_pid_sched_operations), | |
2825 | #endif | |
2826 | #ifdef CONFIG_HAVE_ARCH_TRACEHOOK | |
2827 | INF("syscall", S_IRUSR, proc_pid_syscall), | |
2828 | #endif | |
2829 | INF("cmdline", S_IRUGO, proc_pid_cmdline), | |
2830 | ONE("stat", S_IRUGO, proc_tid_stat), | |
2831 | ONE("statm", S_IRUGO, proc_pid_statm), | |
2832 | REG("maps", S_IRUGO, proc_maps_operations), | |
2833 | #ifdef CONFIG_NUMA | |
2834 | REG("numa_maps", S_IRUGO, proc_numa_maps_operations), | |
2835 | #endif | |
2836 | REG("mem", S_IRUSR|S_IWUSR, proc_mem_operations), | |
2837 | LNK("cwd", proc_cwd_link), | |
2838 | LNK("root", proc_root_link), | |
2839 | LNK("exe", proc_exe_link), | |
2840 | REG("mounts", S_IRUGO, proc_mounts_operations), | |
2841 | REG("mountinfo", S_IRUGO, proc_mountinfo_operations), | |
2842 | #ifdef CONFIG_PROC_PAGE_MONITOR | |
2843 | REG("clear_refs", S_IWUSR, proc_clear_refs_operations), | |
2844 | REG("smaps", S_IRUGO, proc_smaps_operations), | |
2845 | REG("pagemap", S_IRUSR, proc_pagemap_operations), | |
2846 | #endif | |
2847 | #ifdef CONFIG_SECURITY | |
2848 | DIR("attr", S_IRUGO|S_IXUGO, proc_attr_dir_inode_operations, proc_attr_dir_operations), | |
2849 | #endif | |
2850 | #ifdef CONFIG_KALLSYMS | |
2851 | INF("wchan", S_IRUGO, proc_pid_wchan), | |
2852 | #endif | |
2853 | #ifdef CONFIG_STACKTRACE | |
2854 | ONE("stack", S_IRUSR, proc_pid_stack), | |
2855 | #endif | |
2856 | #ifdef CONFIG_SCHEDSTATS | |
2857 | INF("schedstat", S_IRUGO, proc_pid_schedstat), | |
2858 | #endif | |
2859 | #ifdef CONFIG_LATENCYTOP | |
2860 | REG("latency", S_IRUGO, proc_lstats_operations), | |
2861 | #endif | |
2862 | #ifdef CONFIG_PROC_PID_CPUSET | |
2863 | REG("cpuset", S_IRUGO, proc_cpuset_operations), | |
2864 | #endif | |
2865 | #ifdef CONFIG_CGROUPS | |
2866 | REG("cgroup", S_IRUGO, proc_cgroup_operations), | |
2867 | #endif | |
2868 | INF("oom_score", S_IRUGO, proc_oom_score), | |
2869 | REG("oom_adj", S_IRUGO|S_IWUSR, proc_oom_adjust_operations), | |
2870 | #ifdef CONFIG_AUDITSYSCALL | |
2871 | REG("loginuid", S_IWUSR|S_IRUGO, proc_loginuid_operations), | |
2872 | REG("sessionid", S_IRUSR, proc_sessionid_operations), | |
2873 | #endif | |
2874 | #ifdef CONFIG_FAULT_INJECTION | |
2875 | REG("make-it-fail", S_IRUGO|S_IWUSR, proc_fault_inject_operations), | |
2876 | #endif | |
2877 | #ifdef CONFIG_TASK_IO_ACCOUNTING | |
2878 | INF("io", S_IRUGO, proc_tid_io_accounting), | |
2879 | #endif | |
2880 | }; | |
2881 | ||
2882 | static int proc_tid_base_readdir(struct file * filp, | |
2883 | void * dirent, filldir_t filldir) | |
2884 | { | |
2885 | return proc_pident_readdir(filp,dirent,filldir, | |
2886 | tid_base_stuff,ARRAY_SIZE(tid_base_stuff)); | |
2887 | } | |
2888 | ||
2889 | static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){ | |
2890 | return proc_pident_lookup(dir, dentry, | |
2891 | tid_base_stuff, ARRAY_SIZE(tid_base_stuff)); | |
2892 | } | |
2893 | ||
2894 | static const struct file_operations proc_tid_base_operations = { | |
2895 | .read = generic_read_dir, | |
2896 | .readdir = proc_tid_base_readdir, | |
2897 | }; | |
2898 | ||
2899 | static const struct inode_operations proc_tid_base_inode_operations = { | |
2900 | .lookup = proc_tid_base_lookup, | |
2901 | .getattr = pid_getattr, | |
2902 | .setattr = proc_setattr, | |
2903 | }; | |
2904 | ||
2905 | static struct dentry *proc_task_instantiate(struct inode *dir, | |
2906 | struct dentry *dentry, struct task_struct *task, const void *ptr) | |
2907 | { | |
2908 | struct dentry *error = ERR_PTR(-ENOENT); | |
2909 | struct inode *inode; | |
2910 | inode = proc_pid_make_inode(dir->i_sb, task); | |
2911 | ||
2912 | if (!inode) | |
2913 | goto out; | |
2914 | inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO; | |
2915 | inode->i_op = &proc_tid_base_inode_operations; | |
2916 | inode->i_fop = &proc_tid_base_operations; | |
2917 | inode->i_flags|=S_IMMUTABLE; | |
2918 | ||
2919 | inode->i_nlink = 2 + pid_entry_count_dirs(tid_base_stuff, | |
2920 | ARRAY_SIZE(tid_base_stuff)); | |
2921 | ||
2922 | dentry->d_op = &pid_dentry_operations; | |
2923 | ||
2924 | d_add(dentry, inode); | |
2925 | /* Close the race of the process dying before we return the dentry */ | |
2926 | if (pid_revalidate(dentry, NULL)) | |
2927 | error = NULL; | |
2928 | out: | |
2929 | return error; | |
2930 | } | |
2931 | ||
2932 | static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd) | |
2933 | { | |
2934 | struct dentry *result = ERR_PTR(-ENOENT); | |
2935 | struct task_struct *task; | |
2936 | struct task_struct *leader = get_proc_task(dir); | |
2937 | unsigned tid; | |
2938 | struct pid_namespace *ns; | |
2939 | ||
2940 | if (!leader) | |
2941 | goto out_no_task; | |
2942 | ||
2943 | tid = name_to_int(dentry); | |
2944 | if (tid == ~0U) | |
2945 | goto out; | |
2946 | ||
2947 | ns = dentry->d_sb->s_fs_info; | |
2948 | rcu_read_lock(); | |
2949 | task = find_task_by_pid_ns(tid, ns); | |
2950 | if (task) | |
2951 | get_task_struct(task); | |
2952 | rcu_read_unlock(); | |
2953 | if (!task) | |
2954 | goto out; | |
2955 | if (!same_thread_group(leader, task)) | |
2956 | goto out_drop_task; | |
2957 | ||
2958 | result = proc_task_instantiate(dir, dentry, task, NULL); | |
2959 | out_drop_task: | |
2960 | put_task_struct(task); | |
2961 | out: | |
2962 | put_task_struct(leader); | |
2963 | out_no_task: | |
2964 | return result; | |
2965 | } | |
2966 | ||
2967 | /* | |
2968 | * Find the first tid of a thread group to return to user space. | |
2969 | * | |
2970 | * Usually this is just the thread group leader, but if the users | |
2971 | * buffer was too small or there was a seek into the middle of the | |
2972 | * directory we have more work todo. | |
2973 | * | |
2974 | * In the case of a short read we start with find_task_by_pid. | |
2975 | * | |
2976 | * In the case of a seek we start with the leader and walk nr | |
2977 | * threads past it. | |
2978 | */ | |
2979 | static struct task_struct *first_tid(struct task_struct *leader, | |
2980 | int tid, int nr, struct pid_namespace *ns) | |
2981 | { | |
2982 | struct task_struct *pos; | |
2983 | ||
2984 | rcu_read_lock(); | |
2985 | /* Attempt to start with the pid of a thread */ | |
2986 | if (tid && (nr > 0)) { | |
2987 | pos = find_task_by_pid_ns(tid, ns); | |
2988 | if (pos && (pos->group_leader == leader)) | |
2989 | goto found; | |
2990 | } | |
2991 | ||
2992 | /* If nr exceeds the number of threads there is nothing todo */ | |
2993 | pos = NULL; | |
2994 | if (nr && nr >= get_nr_threads(leader)) | |
2995 | goto out; | |
2996 | ||
2997 | /* If we haven't found our starting place yet start | |
2998 | * with the leader and walk nr threads forward. | |
2999 | */ | |
3000 | for (pos = leader; nr > 0; --nr) { | |
3001 | pos = next_thread(pos); | |
3002 | if (pos == leader) { | |
3003 | pos = NULL; | |
3004 | goto out; | |
3005 | } | |
3006 | } | |
3007 | found: | |
3008 | get_task_struct(pos); | |
3009 | out: | |
3010 | rcu_read_unlock(); | |
3011 | return pos; | |
3012 | } | |
3013 | ||
3014 | /* | |
3015 | * Find the next thread in the thread list. | |
3016 | * Return NULL if there is an error or no next thread. | |
3017 | * | |
3018 | * The reference to the input task_struct is released. | |
3019 | */ | |
3020 | static struct task_struct *next_tid(struct task_struct *start) | |
3021 | { | |
3022 | struct task_struct *pos = NULL; | |
3023 | rcu_read_lock(); | |
3024 | if (pid_alive(start)) { | |
3025 | pos = next_thread(start); | |
3026 | if (thread_group_leader(pos)) | |
3027 | pos = NULL; | |
3028 | else | |
3029 | get_task_struct(pos); | |
3030 | } | |
3031 | rcu_read_unlock(); | |
3032 | put_task_struct(start); | |
3033 | return pos; | |
3034 | } | |
3035 | ||
3036 | static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir, | |
3037 | struct task_struct *task, int tid) | |
3038 | { | |
3039 | char name[PROC_NUMBUF]; | |
3040 | int len = snprintf(name, sizeof(name), "%d", tid); | |
3041 | return proc_fill_cache(filp, dirent, filldir, name, len, | |
3042 | proc_task_instantiate, task, NULL); | |
3043 | } | |
3044 | ||
3045 | /* for the /proc/TGID/task/ directories */ | |
3046 | static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir) | |
3047 | { | |
3048 | struct dentry *dentry = filp->f_path.dentry; | |
3049 | struct inode *inode = dentry->d_inode; | |
3050 | struct task_struct *leader = NULL; | |
3051 | struct task_struct *task; | |
3052 | int retval = -ENOENT; | |
3053 | ino_t ino; | |
3054 | int tid; | |
3055 | struct pid_namespace *ns; | |
3056 | ||
3057 | task = get_proc_task(inode); | |
3058 | if (!task) | |
3059 | goto out_no_task; | |
3060 | rcu_read_lock(); | |
3061 | if (pid_alive(task)) { | |
3062 | leader = task->group_leader; | |
3063 | get_task_struct(leader); | |
3064 | } | |
3065 | rcu_read_unlock(); | |
3066 | put_task_struct(task); | |
3067 | if (!leader) | |
3068 | goto out_no_task; | |
3069 | retval = 0; | |
3070 | ||
3071 | switch ((unsigned long)filp->f_pos) { | |
3072 | case 0: | |
3073 | ino = inode->i_ino; | |
3074 | if (filldir(dirent, ".", 1, filp->f_pos, ino, DT_DIR) < 0) | |
3075 | goto out; | |
3076 | filp->f_pos++; | |
3077 | /* fall through */ | |
3078 | case 1: | |
3079 | ino = parent_ino(dentry); | |
3080 | if (filldir(dirent, "..", 2, filp->f_pos, ino, DT_DIR) < 0) | |
3081 | goto out; | |
3082 | filp->f_pos++; | |
3083 | /* fall through */ | |
3084 | } | |
3085 | ||
3086 | /* f_version caches the tgid value that the last readdir call couldn't | |
3087 | * return. lseek aka telldir automagically resets f_version to 0. | |
3088 | */ | |
3089 | ns = filp->f_dentry->d_sb->s_fs_info; | |
3090 | tid = (int)filp->f_version; | |
3091 | filp->f_version = 0; | |
3092 | for (task = first_tid(leader, tid, filp->f_pos - 2, ns); | |
3093 | task; | |
3094 | task = next_tid(task), filp->f_pos++) { | |
3095 | tid = task_pid_nr_ns(task, ns); | |
3096 | if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) { | |
3097 | /* returning this tgid failed, save it as the first | |
3098 | * pid for the next readir call */ | |
3099 | filp->f_version = (u64)tid; | |
3100 | put_task_struct(task); | |
3101 | break; | |
3102 | } | |
3103 | } | |
3104 | out: | |
3105 | put_task_struct(leader); | |
3106 | out_no_task: | |
3107 | return retval; | |
3108 | } | |
3109 | ||
3110 | static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) | |
3111 | { | |
3112 | struct inode *inode = dentry->d_inode; | |
3113 | struct task_struct *p = get_proc_task(inode); | |
3114 | generic_fillattr(inode, stat); | |
3115 | ||
3116 | if (p) { | |
3117 | stat->nlink += get_nr_threads(p); | |
3118 | put_task_struct(p); | |
3119 | } | |
3120 | ||
3121 | return 0; | |
3122 | } | |
3123 | ||
3124 | static const struct inode_operations proc_task_inode_operations = { | |
3125 | .lookup = proc_task_lookup, | |
3126 | .getattr = proc_task_getattr, | |
3127 | .setattr = proc_setattr, | |
3128 | }; | |
3129 | ||
3130 | static const struct file_operations proc_task_operations = { | |
3131 | .read = generic_read_dir, | |
3132 | .readdir = proc_task_readdir, | |
3133 | }; |