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v3.1
 
  1/*
  2 *  linux/fs/proc/array.c
  3 *
  4 *  Copyright (C) 1992  by Linus Torvalds
  5 *  based on ideas by Darren Senn
  6 *
  7 * Fixes:
  8 * Michael. K. Johnson: stat,statm extensions.
  9 *                      <johnsonm@stolaf.edu>
 10 *
 11 * Pauline Middelink :  Made cmdline,envline only break at '\0's, to
 12 *                      make sure SET_PROCTITLE works. Also removed
 13 *                      bad '!' which forced address recalculation for
 14 *                      EVERY character on the current page.
 15 *                      <middelin@polyware.iaf.nl>
 16 *
 17 * Danny ter Haar    :	added cpuinfo
 18 *			<dth@cistron.nl>
 19 *
 20 * Alessandro Rubini :  profile extension.
 21 *                      <rubini@ipvvis.unipv.it>
 22 *
 23 * Jeff Tranter      :  added BogoMips field to cpuinfo
 24 *                      <Jeff_Tranter@Mitel.COM>
 25 *
 26 * Bruno Haible      :  remove 4K limit for the maps file
 27 *			<haible@ma2s2.mathematik.uni-karlsruhe.de>
 28 *
 29 * Yves Arrouye      :  remove removal of trailing spaces in get_array.
 30 *			<Yves.Arrouye@marin.fdn.fr>
 31 *
 32 * Jerome Forissier  :  added per-CPU time information to /proc/stat
 33 *                      and /proc/<pid>/cpu extension
 34 *                      <forissier@isia.cma.fr>
 35 *			- Incorporation and non-SMP safe operation
 36 *			of forissier patch in 2.1.78 by
 37 *			Hans Marcus <crowbar@concepts.nl>
 38 *
 39 * aeb@cwi.nl        :  /proc/partitions
 40 *
 41 *
 42 * Alan Cox	     :  security fixes.
 43 *			<alan@lxorguk.ukuu.org.uk>
 44 *
 45 * Al Viro           :  safe handling of mm_struct
 46 *
 47 * Gerhard Wichert   :  added BIGMEM support
 48 * Siemens AG           <Gerhard.Wichert@pdb.siemens.de>
 49 *
 50 * Al Viro & Jeff Garzik :  moved most of the thing into base.c and
 51 *			 :  proc_misc.c. The rest may eventually go into
 52 *			 :  base.c too.
 53 */
 54
 55#include <linux/types.h>
 56#include <linux/errno.h>
 57#include <linux/time.h>
 58#include <linux/kernel.h>
 59#include <linux/kernel_stat.h>
 60#include <linux/tty.h>
 61#include <linux/string.h>
 62#include <linux/mman.h>
 
 
 
 
 
 63#include <linux/proc_fs.h>
 64#include <linux/ioport.h>
 65#include <linux/uaccess.h>
 66#include <linux/io.h>
 67#include <linux/mm.h>
 68#include <linux/hugetlb.h>
 69#include <linux/pagemap.h>
 70#include <linux/swap.h>
 71#include <linux/smp.h>
 72#include <linux/signal.h>
 73#include <linux/highmem.h>
 74#include <linux/file.h>
 75#include <linux/fdtable.h>
 76#include <linux/times.h>
 77#include <linux/cpuset.h>
 78#include <linux/rcupdate.h>
 79#include <linux/delayacct.h>
 80#include <linux/seq_file.h>
 81#include <linux/pid_namespace.h>
 
 82#include <linux/ptrace.h>
 83#include <linux/tracehook.h>
 
 
 
 84
 85#include <asm/pgtable.h>
 86#include <asm/processor.h>
 87#include "internal.h"
 88
 89static inline void task_name(struct seq_file *m, struct task_struct *p)
 90{
 91	int i;
 92	char *buf, *end;
 93	char *name;
 94	char tcomm[sizeof(p->comm)];
 95
 96	get_task_comm(tcomm, p);
 97
 98	seq_puts(m, "Name:\t");
 99	end = m->buf + m->size;
100	buf = m->buf + m->count;
101	name = tcomm;
102	i = sizeof(tcomm);
103	while (i && (buf < end)) {
104		unsigned char c = *name;
105		name++;
106		i--;
107		*buf = c;
108		if (!c)
109			break;
110		if (c == '\\') {
111			buf++;
112			if (buf < end)
113				*buf++ = c;
114			continue;
115		}
116		if (c == '\n') {
117			*buf++ = '\\';
118			if (buf < end)
119				*buf++ = 'n';
120			continue;
121		}
122		buf++;
123	}
124	m->count = buf - m->buf;
125	seq_putc(m, '\n');
126}
127
128/*
129 * The task state array is a strange "bitmap" of
130 * reasons to sleep. Thus "running" is zero, and
131 * you can test for combinations of others with
132 * simple bit tests.
133 */
134static const char * const task_state_array[] = {
135	"R (running)",		/*   0 */
136	"S (sleeping)",		/*   1 */
137	"D (disk sleep)",	/*   2 */
138	"T (stopped)",		/*   4 */
139	"t (tracing stop)",	/*   8 */
140	"Z (zombie)",		/*  16 */
141	"X (dead)",		/*  32 */
142	"x (dead)",		/*  64 */
143	"K (wakekill)",		/* 128 */
144	"W (waking)",		/* 256 */
 
 
 
145};
146
147static inline const char *get_task_state(struct task_struct *tsk)
148{
149	unsigned int state = (tsk->state & TASK_REPORT) | tsk->exit_state;
150	const char * const *p = &task_state_array[0];
151
152	BUILD_BUG_ON(1 + ilog2(TASK_STATE_MAX) != ARRAY_SIZE(task_state_array));
153
154	while (state) {
155		p++;
156		state >>= 1;
157	}
158	return *p;
159}
160
161static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
162				struct pid *pid, struct task_struct *p)
163{
 
164	struct group_info *group_info;
165	int g;
166	struct fdtable *fdt = NULL;
167	const struct cred *cred;
168	pid_t ppid, tpid;
 
169
170	rcu_read_lock();
171	ppid = pid_alive(p) ?
172		task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0;
173	tpid = 0;
174	if (pid_alive(p)) {
175		struct task_struct *tracer = ptrace_parent(p);
176		if (tracer)
177			tpid = task_pid_nr_ns(tracer, ns);
178	}
 
179	cred = get_task_cred(p);
180	seq_printf(m,
181		"State:\t%s\n"
182		"Tgid:\t%d\n"
183		"Pid:\t%d\n"
184		"PPid:\t%d\n"
185		"TracerPid:\t%d\n"
186		"Uid:\t%d\t%d\t%d\t%d\n"
187		"Gid:\t%d\t%d\t%d\t%d\n",
188		get_task_state(p),
189		task_tgid_nr_ns(p, ns),
190		pid_nr_ns(pid, ns),
191		ppid, tpid,
192		cred->uid, cred->euid, cred->suid, cred->fsuid,
193		cred->gid, cred->egid, cred->sgid, cred->fsgid);
194
195	task_lock(p);
 
 
196	if (p->files)
197		fdt = files_fdtable(p->files);
198	seq_printf(m,
199		"FDSize:\t%d\n"
200		"Groups:\t",
201		fdt ? fdt->max_fds : 0);
202	rcu_read_unlock();
203
204	group_info = cred->group_info;
205	task_unlock(p);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
206
207	for (g = 0; g < min(group_info->ngroups, NGROUPS_SMALL); g++)
208		seq_printf(m, "%d ", GROUP_AT(group_info, g));
 
 
 
209	put_cred(cred);
 
 
210
 
 
 
 
 
 
 
 
 
 
 
 
 
 
211	seq_putc(m, '\n');
212}
213
214static void render_sigset_t(struct seq_file *m, const char *header,
215				sigset_t *set)
216{
217	int i;
218
219	seq_puts(m, header);
220
221	i = _NSIG;
222	do {
223		int x = 0;
224
225		i -= 4;
226		if (sigismember(set, i+1)) x |= 1;
227		if (sigismember(set, i+2)) x |= 2;
228		if (sigismember(set, i+3)) x |= 4;
229		if (sigismember(set, i+4)) x |= 8;
230		seq_printf(m, "%x", x);
231	} while (i >= 4);
232
233	seq_putc(m, '\n');
234}
235
236static void collect_sigign_sigcatch(struct task_struct *p, sigset_t *ign,
237				    sigset_t *catch)
238{
239	struct k_sigaction *k;
240	int i;
241
242	k = p->sighand->action;
243	for (i = 1; i <= _NSIG; ++i, ++k) {
244		if (k->sa.sa_handler == SIG_IGN)
245			sigaddset(ign, i);
246		else if (k->sa.sa_handler != SIG_DFL)
247			sigaddset(catch, i);
248	}
249}
250
251static inline void task_sig(struct seq_file *m, struct task_struct *p)
252{
253	unsigned long flags;
254	sigset_t pending, shpending, blocked, ignored, caught;
255	int num_threads = 0;
256	unsigned long qsize = 0;
257	unsigned long qlim = 0;
258
259	sigemptyset(&pending);
260	sigemptyset(&shpending);
261	sigemptyset(&blocked);
262	sigemptyset(&ignored);
263	sigemptyset(&caught);
264
265	if (lock_task_sighand(p, &flags)) {
266		pending = p->pending.signal;
267		shpending = p->signal->shared_pending.signal;
268		blocked = p->blocked;
269		collect_sigign_sigcatch(p, &ignored, &caught);
270		num_threads = get_nr_threads(p);
271		rcu_read_lock();  /* FIXME: is this correct? */
272		qsize = atomic_read(&__task_cred(p)->user->sigpending);
273		rcu_read_unlock();
274		qlim = task_rlimit(p, RLIMIT_SIGPENDING);
275		unlock_task_sighand(p, &flags);
276	}
277
278	seq_printf(m, "Threads:\t%d\n", num_threads);
279	seq_printf(m, "SigQ:\t%lu/%lu\n", qsize, qlim);
 
280
281	/* render them all */
282	render_sigset_t(m, "SigPnd:\t", &pending);
283	render_sigset_t(m, "ShdPnd:\t", &shpending);
284	render_sigset_t(m, "SigBlk:\t", &blocked);
285	render_sigset_t(m, "SigIgn:\t", &ignored);
286	render_sigset_t(m, "SigCgt:\t", &caught);
287}
288
289static void render_cap_t(struct seq_file *m, const char *header,
290			kernel_cap_t *a)
291{
292	unsigned __capi;
293
294	seq_puts(m, header);
295	CAP_FOR_EACH_U32(__capi) {
296		seq_printf(m, "%08x",
297			   a->cap[(_KERNEL_CAPABILITY_U32S-1) - __capi]);
298	}
299	seq_putc(m, '\n');
300}
301
302static inline void task_cap(struct seq_file *m, struct task_struct *p)
303{
304	const struct cred *cred;
305	kernel_cap_t cap_inheritable, cap_permitted, cap_effective, cap_bset;
 
306
307	rcu_read_lock();
308	cred = __task_cred(p);
309	cap_inheritable	= cred->cap_inheritable;
310	cap_permitted	= cred->cap_permitted;
311	cap_effective	= cred->cap_effective;
312	cap_bset	= cred->cap_bset;
 
313	rcu_read_unlock();
314
315	render_cap_t(m, "CapInh:\t", &cap_inheritable);
316	render_cap_t(m, "CapPrm:\t", &cap_permitted);
317	render_cap_t(m, "CapEff:\t", &cap_effective);
318	render_cap_t(m, "CapBnd:\t", &cap_bset);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
319}
320
321static inline void task_context_switch_counts(struct seq_file *m,
322						struct task_struct *p)
323{
324	seq_printf(m,	"voluntary_ctxt_switches:\t%lu\n"
325			"nonvoluntary_ctxt_switches:\t%lu\n",
326			p->nvcsw,
327			p->nivcsw);
328}
329
330static void task_cpus_allowed(struct seq_file *m, struct task_struct *task)
331{
332	seq_puts(m, "Cpus_allowed:\t");
333	seq_cpumask(m, &task->cpus_allowed);
334	seq_putc(m, '\n');
335	seq_puts(m, "Cpus_allowed_list:\t");
336	seq_cpumask_list(m, &task->cpus_allowed);
 
 
 
 
337	seq_putc(m, '\n');
338}
339
 
 
 
 
 
 
 
 
 
340int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
341			struct pid *pid, struct task_struct *task)
342{
343	struct mm_struct *mm = get_task_mm(task);
344
345	task_name(m, task);
 
 
 
346	task_state(m, ns, pid, task);
347
348	if (mm) {
349		task_mem(m, mm);
 
 
350		mmput(mm);
351	}
352	task_sig(m, task);
353	task_cap(m, task);
 
354	task_cpus_allowed(m, task);
355	cpuset_task_status_allowed(m, task);
356	task_context_switch_counts(m, task);
357	return 0;
358}
359
360static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
361			struct pid *pid, struct task_struct *task, int whole)
362{
363	unsigned long vsize, eip, esp, wchan = ~0UL;
364	long priority, nice;
365	int tty_pgrp = -1, tty_nr = 0;
366	sigset_t sigign, sigcatch;
367	char state;
368	pid_t ppid = 0, pgid = -1, sid = -1;
369	int num_threads = 0;
370	int permitted;
371	struct mm_struct *mm;
372	unsigned long long start_time;
373	unsigned long cmin_flt = 0, cmaj_flt = 0;
374	unsigned long  min_flt = 0,  maj_flt = 0;
375	cputime_t cutime, cstime, utime, stime;
376	cputime_t cgtime, gtime;
377	unsigned long rsslim = 0;
378	char tcomm[sizeof(task->comm)];
379	unsigned long flags;
380
381	state = *get_task_state(task);
382	vsize = eip = esp = 0;
383	permitted = ptrace_may_access(task, PTRACE_MODE_READ);
384	mm = get_task_mm(task);
385	if (mm) {
386		vsize = task_vsize(mm);
387		if (permitted) {
388			eip = KSTK_EIP(task);
389			esp = KSTK_ESP(task);
 
 
 
 
 
 
 
 
 
 
 
 
390		}
391	}
392
393	get_task_comm(tcomm, task);
394
395	sigemptyset(&sigign);
396	sigemptyset(&sigcatch);
397	cutime = cstime = utime = stime = cputime_zero;
398	cgtime = gtime = cputime_zero;
399
400	if (lock_task_sighand(task, &flags)) {
401		struct signal_struct *sig = task->signal;
402
403		if (sig->tty) {
404			struct pid *pgrp = tty_get_pgrp(sig->tty);
405			tty_pgrp = pid_nr_ns(pgrp, ns);
406			put_pid(pgrp);
407			tty_nr = new_encode_dev(tty_devnum(sig->tty));
408		}
409
410		num_threads = get_nr_threads(task);
411		collect_sigign_sigcatch(task, &sigign, &sigcatch);
412
413		cmin_flt = sig->cmin_flt;
414		cmaj_flt = sig->cmaj_flt;
415		cutime = sig->cutime;
416		cstime = sig->cstime;
417		cgtime = sig->cgtime;
418		rsslim = ACCESS_ONCE(sig->rlim[RLIMIT_RSS].rlim_cur);
419
420		/* add up live thread stats at the group level */
421		if (whole) {
422			struct task_struct *t = task;
423			do {
424				min_flt += t->min_flt;
425				maj_flt += t->maj_flt;
426				gtime = cputime_add(gtime, t->gtime);
427				t = next_thread(t);
428			} while (t != task);
429
430			min_flt += sig->min_flt;
431			maj_flt += sig->maj_flt;
432			thread_group_times(task, &utime, &stime);
433			gtime = cputime_add(gtime, sig->gtime);
434		}
435
436		sid = task_session_nr_ns(task, ns);
437		ppid = task_tgid_nr_ns(task->real_parent, ns);
438		pgid = task_pgrp_nr_ns(task, ns);
439
440		unlock_task_sighand(task, &flags);
441	}
442
443	if (permitted && (!whole || num_threads < 2))
444		wchan = get_wchan(task);
445	if (!whole) {
446		min_flt = task->min_flt;
447		maj_flt = task->maj_flt;
448		task_times(task, &utime, &stime);
449		gtime = task->gtime;
450	}
451
452	/* scale priority and nice values from timeslices to -20..20 */
453	/* to make it look like a "normal" Unix priority/nice value  */
454	priority = task_prio(task);
455	nice = task_nice(task);
456
457	/* Temporary variable needed for gcc-2.96 */
458	/* convert timespec -> nsec*/
459	start_time =
460		(unsigned long long)task->real_start_time.tv_sec * NSEC_PER_SEC
461				+ task->real_start_time.tv_nsec;
462	/* convert nsec -> ticks */
463	start_time = nsec_to_clock_t(start_time);
464
465	seq_printf(m, "%d (%s) %c %d %d %d %d %d %u %lu \
466%lu %lu %lu %lu %lu %ld %ld %ld %ld %d 0 %llu %lu %ld %lu %lu %lu %lu %lu \
467%lu %lu %lu %lu %lu %lu %lu %lu %d %d %u %u %llu %lu %ld\n",
468		pid_nr_ns(pid, ns),
469		tcomm,
470		state,
471		ppid,
472		pgid,
473		sid,
474		tty_nr,
475		tty_pgrp,
476		task->flags,
477		min_flt,
478		cmin_flt,
479		maj_flt,
480		cmaj_flt,
481		cputime_to_clock_t(utime),
482		cputime_to_clock_t(stime),
483		cputime_to_clock_t(cutime),
484		cputime_to_clock_t(cstime),
485		priority,
486		nice,
487		num_threads,
488		start_time,
489		vsize,
490		mm ? get_mm_rss(mm) : 0,
491		rsslim,
492		mm ? (permitted ? mm->start_code : 1) : 0,
493		mm ? (permitted ? mm->end_code : 1) : 0,
494		(permitted && mm) ? mm->start_stack : 0,
495		esp,
496		eip,
497		/* The signal information here is obsolete.
498		 * It must be decimal for Linux 2.0 compatibility.
499		 * Use /proc/#/status for real-time signals.
500		 */
501		task->pending.signal.sig[0] & 0x7fffffffUL,
502		task->blocked.sig[0] & 0x7fffffffUL,
503		sigign      .sig[0] & 0x7fffffffUL,
504		sigcatch    .sig[0] & 0x7fffffffUL,
505		wchan,
506		0UL,
507		0UL,
508		task->exit_signal,
509		task_cpu(task),
510		task->rt_priority,
511		task->policy,
512		(unsigned long long)delayacct_blkio_ticks(task),
513		cputime_to_clock_t(gtime),
514		cputime_to_clock_t(cgtime));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
515	if (mm)
516		mmput(mm);
517	return 0;
518}
519
520int proc_tid_stat(struct seq_file *m, struct pid_namespace *ns,
521			struct pid *pid, struct task_struct *task)
522{
523	return do_task_stat(m, ns, pid, task, 0);
524}
525
526int proc_tgid_stat(struct seq_file *m, struct pid_namespace *ns,
527			struct pid *pid, struct task_struct *task)
528{
529	return do_task_stat(m, ns, pid, task, 1);
530}
531
532int proc_pid_statm(struct seq_file *m, struct pid_namespace *ns,
533			struct pid *pid, struct task_struct *task)
534{
535	unsigned long size = 0, resident = 0, shared = 0, text = 0, data = 0;
536	struct mm_struct *mm = get_task_mm(task);
537
538	if (mm) {
539		size = task_statm(mm, &shared, &text, &data, &resident);
540		mmput(mm);
541	}
542	seq_printf(m, "%lu %lu %lu %lu 0 %lu 0\n",
543			size, resident, shared, text, data);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
544
 
545	return 0;
546}
v5.4
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 *  linux/fs/proc/array.c
  4 *
  5 *  Copyright (C) 1992  by Linus Torvalds
  6 *  based on ideas by Darren Senn
  7 *
  8 * Fixes:
  9 * Michael. K. Johnson: stat,statm extensions.
 10 *                      <johnsonm@stolaf.edu>
 11 *
 12 * Pauline Middelink :  Made cmdline,envline only break at '\0's, to
 13 *                      make sure SET_PROCTITLE works. Also removed
 14 *                      bad '!' which forced address recalculation for
 15 *                      EVERY character on the current page.
 16 *                      <middelin@polyware.iaf.nl>
 17 *
 18 * Danny ter Haar    :	added cpuinfo
 19 *			<dth@cistron.nl>
 20 *
 21 * Alessandro Rubini :  profile extension.
 22 *                      <rubini@ipvvis.unipv.it>
 23 *
 24 * Jeff Tranter      :  added BogoMips field to cpuinfo
 25 *                      <Jeff_Tranter@Mitel.COM>
 26 *
 27 * Bruno Haible      :  remove 4K limit for the maps file
 28 *			<haible@ma2s2.mathematik.uni-karlsruhe.de>
 29 *
 30 * Yves Arrouye      :  remove removal of trailing spaces in get_array.
 31 *			<Yves.Arrouye@marin.fdn.fr>
 32 *
 33 * Jerome Forissier  :  added per-CPU time information to /proc/stat
 34 *                      and /proc/<pid>/cpu extension
 35 *                      <forissier@isia.cma.fr>
 36 *			- Incorporation and non-SMP safe operation
 37 *			of forissier patch in 2.1.78 by
 38 *			Hans Marcus <crowbar@concepts.nl>
 39 *
 40 * aeb@cwi.nl        :  /proc/partitions
 41 *
 42 *
 43 * Alan Cox	     :  security fixes.
 44 *			<alan@lxorguk.ukuu.org.uk>
 45 *
 46 * Al Viro           :  safe handling of mm_struct
 47 *
 48 * Gerhard Wichert   :  added BIGMEM support
 49 * Siemens AG           <Gerhard.Wichert@pdb.siemens.de>
 50 *
 51 * Al Viro & Jeff Garzik :  moved most of the thing into base.c and
 52 *			 :  proc_misc.c. The rest may eventually go into
 53 *			 :  base.c too.
 54 */
 55
 56#include <linux/types.h>
 57#include <linux/errno.h>
 58#include <linux/time.h>
 59#include <linux/kernel.h>
 60#include <linux/kernel_stat.h>
 61#include <linux/tty.h>
 62#include <linux/string.h>
 63#include <linux/mman.h>
 64#include <linux/sched/mm.h>
 65#include <linux/sched/numa_balancing.h>
 66#include <linux/sched/task_stack.h>
 67#include <linux/sched/task.h>
 68#include <linux/sched/cputime.h>
 69#include <linux/proc_fs.h>
 70#include <linux/ioport.h>
 71#include <linux/uaccess.h>
 72#include <linux/io.h>
 73#include <linux/mm.h>
 74#include <linux/hugetlb.h>
 75#include <linux/pagemap.h>
 76#include <linux/swap.h>
 77#include <linux/smp.h>
 78#include <linux/signal.h>
 79#include <linux/highmem.h>
 80#include <linux/file.h>
 81#include <linux/fdtable.h>
 82#include <linux/times.h>
 83#include <linux/cpuset.h>
 84#include <linux/rcupdate.h>
 85#include <linux/delayacct.h>
 86#include <linux/seq_file.h>
 87#include <linux/pid_namespace.h>
 88#include <linux/prctl.h>
 89#include <linux/ptrace.h>
 90#include <linux/tracehook.h>
 91#include <linux/string_helpers.h>
 92#include <linux/user_namespace.h>
 93#include <linux/fs_struct.h>
 94
 95#include <asm/pgtable.h>
 96#include <asm/processor.h>
 97#include "internal.h"
 98
 99void proc_task_name(struct seq_file *m, struct task_struct *p, bool escape)
100{
101	char *buf;
102	size_t size;
103	char tcomm[64];
104	int ret;
105
106	if (p->flags & PF_WQ_WORKER)
107		wq_worker_comm(tcomm, sizeof(tcomm), p);
108	else
109		__get_task_comm(tcomm, sizeof(tcomm), p);
110
111	size = seq_get_buf(m, &buf);
112	if (escape) {
113		ret = string_escape_str(tcomm, buf, size,
114					ESCAPE_SPACE | ESCAPE_SPECIAL, "\n\\");
115		if (ret >= size)
116			ret = -1;
117	} else {
118		ret = strscpy(buf, tcomm, size);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
119	}
120
121	seq_commit(m, ret);
122}
123
124/*
125 * The task state array is a strange "bitmap" of
126 * reasons to sleep. Thus "running" is zero, and
127 * you can test for combinations of others with
128 * simple bit tests.
129 */
130static const char * const task_state_array[] = {
131
132	/* states in TASK_REPORT: */
133	"R (running)",		/* 0x00 */
134	"S (sleeping)",		/* 0x01 */
135	"D (disk sleep)",	/* 0x02 */
136	"T (stopped)",		/* 0x04 */
137	"t (tracing stop)",	/* 0x08 */
138	"X (dead)",		/* 0x10 */
139	"Z (zombie)",		/* 0x20 */
140	"P (parked)",		/* 0x40 */
141
142	/* states beyond TASK_REPORT: */
143	"I (idle)",		/* 0x80 */
144};
145
146static inline const char *get_task_state(struct task_struct *tsk)
147{
148	BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != ARRAY_SIZE(task_state_array));
149	return task_state_array[task_state_index(tsk)];
 
 
 
 
 
 
 
 
150}
151
152static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
153				struct pid *pid, struct task_struct *p)
154{
155	struct user_namespace *user_ns = seq_user_ns(m);
156	struct group_info *group_info;
157	int g, umask = -1;
158	struct task_struct *tracer;
159	const struct cred *cred;
160	pid_t ppid, tpid = 0, tgid, ngid;
161	unsigned int max_fds = 0;
162
163	rcu_read_lock();
164	ppid = pid_alive(p) ?
165		task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0;
166
167	tracer = ptrace_parent(p);
168	if (tracer)
169		tpid = task_pid_nr_ns(tracer, ns);
170
171	tgid = task_tgid_nr_ns(p, ns);
172	ngid = task_numa_group_id(p);
173	cred = get_task_cred(p);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
174
175	task_lock(p);
176	if (p->fs)
177		umask = p->fs->umask;
178	if (p->files)
179		max_fds = files_fdtable(p->files)->max_fds;
180	task_unlock(p);
 
 
 
181	rcu_read_unlock();
182
183	if (umask >= 0)
184		seq_printf(m, "Umask:\t%#04o\n", umask);
185	seq_puts(m, "State:\t");
186	seq_puts(m, get_task_state(p));
187
188	seq_put_decimal_ull(m, "\nTgid:\t", tgid);
189	seq_put_decimal_ull(m, "\nNgid:\t", ngid);
190	seq_put_decimal_ull(m, "\nPid:\t", pid_nr_ns(pid, ns));
191	seq_put_decimal_ull(m, "\nPPid:\t", ppid);
192	seq_put_decimal_ull(m, "\nTracerPid:\t", tpid);
193	seq_put_decimal_ull(m, "\nUid:\t", from_kuid_munged(user_ns, cred->uid));
194	seq_put_decimal_ull(m, "\t", from_kuid_munged(user_ns, cred->euid));
195	seq_put_decimal_ull(m, "\t", from_kuid_munged(user_ns, cred->suid));
196	seq_put_decimal_ull(m, "\t", from_kuid_munged(user_ns, cred->fsuid));
197	seq_put_decimal_ull(m, "\nGid:\t", from_kgid_munged(user_ns, cred->gid));
198	seq_put_decimal_ull(m, "\t", from_kgid_munged(user_ns, cred->egid));
199	seq_put_decimal_ull(m, "\t", from_kgid_munged(user_ns, cred->sgid));
200	seq_put_decimal_ull(m, "\t", from_kgid_munged(user_ns, cred->fsgid));
201	seq_put_decimal_ull(m, "\nFDSize:\t", max_fds);
202
203	seq_puts(m, "\nGroups:\t");
204	group_info = cred->group_info;
205	for (g = 0; g < group_info->ngroups; g++)
206		seq_put_decimal_ull(m, g ? " " : "",
207				from_kgid_munged(user_ns, group_info->gid[g]));
208	put_cred(cred);
209	/* Trailing space shouldn't have been added in the first place. */
210	seq_putc(m, ' ');
211
212#ifdef CONFIG_PID_NS
213	seq_puts(m, "\nNStgid:");
214	for (g = ns->level; g <= pid->level; g++)
215		seq_put_decimal_ull(m, "\t", task_tgid_nr_ns(p, pid->numbers[g].ns));
216	seq_puts(m, "\nNSpid:");
217	for (g = ns->level; g <= pid->level; g++)
218		seq_put_decimal_ull(m, "\t", task_pid_nr_ns(p, pid->numbers[g].ns));
219	seq_puts(m, "\nNSpgid:");
220	for (g = ns->level; g <= pid->level; g++)
221		seq_put_decimal_ull(m, "\t", task_pgrp_nr_ns(p, pid->numbers[g].ns));
222	seq_puts(m, "\nNSsid:");
223	for (g = ns->level; g <= pid->level; g++)
224		seq_put_decimal_ull(m, "\t", task_session_nr_ns(p, pid->numbers[g].ns));
225#endif
226	seq_putc(m, '\n');
227}
228
229void render_sigset_t(struct seq_file *m, const char *header,
230				sigset_t *set)
231{
232	int i;
233
234	seq_puts(m, header);
235
236	i = _NSIG;
237	do {
238		int x = 0;
239
240		i -= 4;
241		if (sigismember(set, i+1)) x |= 1;
242		if (sigismember(set, i+2)) x |= 2;
243		if (sigismember(set, i+3)) x |= 4;
244		if (sigismember(set, i+4)) x |= 8;
245		seq_putc(m, hex_asc[x]);
246	} while (i >= 4);
247
248	seq_putc(m, '\n');
249}
250
251static void collect_sigign_sigcatch(struct task_struct *p, sigset_t *ign,
252				    sigset_t *catch)
253{
254	struct k_sigaction *k;
255	int i;
256
257	k = p->sighand->action;
258	for (i = 1; i <= _NSIG; ++i, ++k) {
259		if (k->sa.sa_handler == SIG_IGN)
260			sigaddset(ign, i);
261		else if (k->sa.sa_handler != SIG_DFL)
262			sigaddset(catch, i);
263	}
264}
265
266static inline void task_sig(struct seq_file *m, struct task_struct *p)
267{
268	unsigned long flags;
269	sigset_t pending, shpending, blocked, ignored, caught;
270	int num_threads = 0;
271	unsigned int qsize = 0;
272	unsigned long qlim = 0;
273
274	sigemptyset(&pending);
275	sigemptyset(&shpending);
276	sigemptyset(&blocked);
277	sigemptyset(&ignored);
278	sigemptyset(&caught);
279
280	if (lock_task_sighand(p, &flags)) {
281		pending = p->pending.signal;
282		shpending = p->signal->shared_pending.signal;
283		blocked = p->blocked;
284		collect_sigign_sigcatch(p, &ignored, &caught);
285		num_threads = get_nr_threads(p);
286		rcu_read_lock();  /* FIXME: is this correct? */
287		qsize = atomic_read(&__task_cred(p)->user->sigpending);
288		rcu_read_unlock();
289		qlim = task_rlimit(p, RLIMIT_SIGPENDING);
290		unlock_task_sighand(p, &flags);
291	}
292
293	seq_put_decimal_ull(m, "Threads:\t", num_threads);
294	seq_put_decimal_ull(m, "\nSigQ:\t", qsize);
295	seq_put_decimal_ull(m, "/", qlim);
296
297	/* render them all */
298	render_sigset_t(m, "\nSigPnd:\t", &pending);
299	render_sigset_t(m, "ShdPnd:\t", &shpending);
300	render_sigset_t(m, "SigBlk:\t", &blocked);
301	render_sigset_t(m, "SigIgn:\t", &ignored);
302	render_sigset_t(m, "SigCgt:\t", &caught);
303}
304
305static void render_cap_t(struct seq_file *m, const char *header,
306			kernel_cap_t *a)
307{
308	unsigned __capi;
309
310	seq_puts(m, header);
311	CAP_FOR_EACH_U32(__capi) {
312		seq_put_hex_ll(m, NULL,
313			   a->cap[CAP_LAST_U32 - __capi], 8);
314	}
315	seq_putc(m, '\n');
316}
317
318static inline void task_cap(struct seq_file *m, struct task_struct *p)
319{
320	const struct cred *cred;
321	kernel_cap_t cap_inheritable, cap_permitted, cap_effective,
322			cap_bset, cap_ambient;
323
324	rcu_read_lock();
325	cred = __task_cred(p);
326	cap_inheritable	= cred->cap_inheritable;
327	cap_permitted	= cred->cap_permitted;
328	cap_effective	= cred->cap_effective;
329	cap_bset	= cred->cap_bset;
330	cap_ambient	= cred->cap_ambient;
331	rcu_read_unlock();
332
333	render_cap_t(m, "CapInh:\t", &cap_inheritable);
334	render_cap_t(m, "CapPrm:\t", &cap_permitted);
335	render_cap_t(m, "CapEff:\t", &cap_effective);
336	render_cap_t(m, "CapBnd:\t", &cap_bset);
337	render_cap_t(m, "CapAmb:\t", &cap_ambient);
338}
339
340static inline void task_seccomp(struct seq_file *m, struct task_struct *p)
341{
342	seq_put_decimal_ull(m, "NoNewPrivs:\t", task_no_new_privs(p));
343#ifdef CONFIG_SECCOMP
344	seq_put_decimal_ull(m, "\nSeccomp:\t", p->seccomp.mode);
345#endif
346	seq_puts(m, "\nSpeculation_Store_Bypass:\t");
347	switch (arch_prctl_spec_ctrl_get(p, PR_SPEC_STORE_BYPASS)) {
348	case -EINVAL:
349		seq_puts(m, "unknown");
350		break;
351	case PR_SPEC_NOT_AFFECTED:
352		seq_puts(m, "not vulnerable");
353		break;
354	case PR_SPEC_PRCTL | PR_SPEC_FORCE_DISABLE:
355		seq_puts(m, "thread force mitigated");
356		break;
357	case PR_SPEC_PRCTL | PR_SPEC_DISABLE:
358		seq_puts(m, "thread mitigated");
359		break;
360	case PR_SPEC_PRCTL | PR_SPEC_ENABLE:
361		seq_puts(m, "thread vulnerable");
362		break;
363	case PR_SPEC_DISABLE:
364		seq_puts(m, "globally mitigated");
365		break;
366	default:
367		seq_puts(m, "vulnerable");
368		break;
369	}
370	seq_putc(m, '\n');
371}
372
373static inline void task_context_switch_counts(struct seq_file *m,
374						struct task_struct *p)
375{
376	seq_put_decimal_ull(m, "voluntary_ctxt_switches:\t", p->nvcsw);
377	seq_put_decimal_ull(m, "\nnonvoluntary_ctxt_switches:\t", p->nivcsw);
378	seq_putc(m, '\n');
 
379}
380
381static void task_cpus_allowed(struct seq_file *m, struct task_struct *task)
382{
383	seq_printf(m, "Cpus_allowed:\t%*pb\n",
384		   cpumask_pr_args(task->cpus_ptr));
385	seq_printf(m, "Cpus_allowed_list:\t%*pbl\n",
386		   cpumask_pr_args(task->cpus_ptr));
387}
388
389static inline void task_core_dumping(struct seq_file *m, struct mm_struct *mm)
390{
391	seq_put_decimal_ull(m, "CoreDumping:\t", !!mm->core_state);
392	seq_putc(m, '\n');
393}
394
395static inline void task_thp_status(struct seq_file *m, struct mm_struct *mm)
396{
397	bool thp_enabled = IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE);
398
399	if (thp_enabled)
400		thp_enabled = !test_bit(MMF_DISABLE_THP, &mm->flags);
401	seq_printf(m, "THP_enabled:\t%d\n", thp_enabled);
402}
403
404int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
405			struct pid *pid, struct task_struct *task)
406{
407	struct mm_struct *mm = get_task_mm(task);
408
409	seq_puts(m, "Name:\t");
410	proc_task_name(m, task, true);
411	seq_putc(m, '\n');
412
413	task_state(m, ns, pid, task);
414
415	if (mm) {
416		task_mem(m, mm);
417		task_core_dumping(m, mm);
418		task_thp_status(m, mm);
419		mmput(mm);
420	}
421	task_sig(m, task);
422	task_cap(m, task);
423	task_seccomp(m, task);
424	task_cpus_allowed(m, task);
425	cpuset_task_status_allowed(m, task);
426	task_context_switch_counts(m, task);
427	return 0;
428}
429
430static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
431			struct pid *pid, struct task_struct *task, int whole)
432{
433	unsigned long vsize, eip, esp, wchan = 0;
434	int priority, nice;
435	int tty_pgrp = -1, tty_nr = 0;
436	sigset_t sigign, sigcatch;
437	char state;
438	pid_t ppid = 0, pgid = -1, sid = -1;
439	int num_threads = 0;
440	int permitted;
441	struct mm_struct *mm;
442	unsigned long long start_time;
443	unsigned long cmin_flt = 0, cmaj_flt = 0;
444	unsigned long  min_flt = 0,  maj_flt = 0;
445	u64 cutime, cstime, utime, stime;
446	u64 cgtime, gtime;
447	unsigned long rsslim = 0;
 
448	unsigned long flags;
449
450	state = *get_task_state(task);
451	vsize = eip = esp = 0;
452	permitted = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS | PTRACE_MODE_NOAUDIT);
453	mm = get_task_mm(task);
454	if (mm) {
455		vsize = task_vsize(mm);
456		/*
457		 * esp and eip are intentionally zeroed out.  There is no
458		 * non-racy way to read them without freezing the task.
459		 * Programs that need reliable values can use ptrace(2).
460		 *
461		 * The only exception is if the task is core dumping because
462		 * a program is not able to use ptrace(2) in that case. It is
463		 * safe because the task has stopped executing permanently.
464		 */
465		if (permitted && (task->flags & (PF_EXITING|PF_DUMPCORE))) {
466			if (try_get_task_stack(task)) {
467				eip = KSTK_EIP(task);
468				esp = KSTK_ESP(task);
469				put_task_stack(task);
470			}
471		}
472	}
473
 
 
474	sigemptyset(&sigign);
475	sigemptyset(&sigcatch);
476	cutime = cstime = utime = stime = 0;
477	cgtime = gtime = 0;
478
479	if (lock_task_sighand(task, &flags)) {
480		struct signal_struct *sig = task->signal;
481
482		if (sig->tty) {
483			struct pid *pgrp = tty_get_pgrp(sig->tty);
484			tty_pgrp = pid_nr_ns(pgrp, ns);
485			put_pid(pgrp);
486			tty_nr = new_encode_dev(tty_devnum(sig->tty));
487		}
488
489		num_threads = get_nr_threads(task);
490		collect_sigign_sigcatch(task, &sigign, &sigcatch);
491
492		cmin_flt = sig->cmin_flt;
493		cmaj_flt = sig->cmaj_flt;
494		cutime = sig->cutime;
495		cstime = sig->cstime;
496		cgtime = sig->cgtime;
497		rsslim = READ_ONCE(sig->rlim[RLIMIT_RSS].rlim_cur);
498
499		/* add up live thread stats at the group level */
500		if (whole) {
501			struct task_struct *t = task;
502			do {
503				min_flt += t->min_flt;
504				maj_flt += t->maj_flt;
505				gtime += task_gtime(t);
506			} while_each_thread(task, t);
 
507
508			min_flt += sig->min_flt;
509			maj_flt += sig->maj_flt;
510			thread_group_cputime_adjusted(task, &utime, &stime);
511			gtime += sig->gtime;
512		}
513
514		sid = task_session_nr_ns(task, ns);
515		ppid = task_tgid_nr_ns(task->real_parent, ns);
516		pgid = task_pgrp_nr_ns(task, ns);
517
518		unlock_task_sighand(task, &flags);
519	}
520
521	if (permitted && (!whole || num_threads < 2))
522		wchan = get_wchan(task);
523	if (!whole) {
524		min_flt = task->min_flt;
525		maj_flt = task->maj_flt;
526		task_cputime_adjusted(task, &utime, &stime);
527		gtime = task_gtime(task);
528	}
529
530	/* scale priority and nice values from timeslices to -20..20 */
531	/* to make it look like a "normal" Unix priority/nice value  */
532	priority = task_prio(task);
533	nice = task_nice(task);
534
 
 
 
 
 
535	/* convert nsec -> ticks */
536	start_time = nsec_to_clock_t(task->real_start_time);
537
538	seq_put_decimal_ull(m, "", pid_nr_ns(pid, ns));
539	seq_puts(m, " (");
540	proc_task_name(m, task, false);
541	seq_puts(m, ") ");
542	seq_putc(m, state);
543	seq_put_decimal_ll(m, " ", ppid);
544	seq_put_decimal_ll(m, " ", pgid);
545	seq_put_decimal_ll(m, " ", sid);
546	seq_put_decimal_ll(m, " ", tty_nr);
547	seq_put_decimal_ll(m, " ", tty_pgrp);
548	seq_put_decimal_ull(m, " ", task->flags);
549	seq_put_decimal_ull(m, " ", min_flt);
550	seq_put_decimal_ull(m, " ", cmin_flt);
551	seq_put_decimal_ull(m, " ", maj_flt);
552	seq_put_decimal_ull(m, " ", cmaj_flt);
553	seq_put_decimal_ull(m, " ", nsec_to_clock_t(utime));
554	seq_put_decimal_ull(m, " ", nsec_to_clock_t(stime));
555	seq_put_decimal_ll(m, " ", nsec_to_clock_t(cutime));
556	seq_put_decimal_ll(m, " ", nsec_to_clock_t(cstime));
557	seq_put_decimal_ll(m, " ", priority);
558	seq_put_decimal_ll(m, " ", nice);
559	seq_put_decimal_ll(m, " ", num_threads);
560	seq_put_decimal_ull(m, " ", 0);
561	seq_put_decimal_ull(m, " ", start_time);
562	seq_put_decimal_ull(m, " ", vsize);
563	seq_put_decimal_ull(m, " ", mm ? get_mm_rss(mm) : 0);
564	seq_put_decimal_ull(m, " ", rsslim);
565	seq_put_decimal_ull(m, " ", mm ? (permitted ? mm->start_code : 1) : 0);
566	seq_put_decimal_ull(m, " ", mm ? (permitted ? mm->end_code : 1) : 0);
567	seq_put_decimal_ull(m, " ", (permitted && mm) ? mm->start_stack : 0);
568	seq_put_decimal_ull(m, " ", esp);
569	seq_put_decimal_ull(m, " ", eip);
570	/* The signal information here is obsolete.
571	 * It must be decimal for Linux 2.0 compatibility.
572	 * Use /proc/#/status for real-time signals.
573	 */
574	seq_put_decimal_ull(m, " ", task->pending.signal.sig[0] & 0x7fffffffUL);
575	seq_put_decimal_ull(m, " ", task->blocked.sig[0] & 0x7fffffffUL);
576	seq_put_decimal_ull(m, " ", sigign.sig[0] & 0x7fffffffUL);
577	seq_put_decimal_ull(m, " ", sigcatch.sig[0] & 0x7fffffffUL);
578
579	/*
580	 * We used to output the absolute kernel address, but that's an
581	 * information leak - so instead we show a 0/1 flag here, to signal
582	 * to user-space whether there's a wchan field in /proc/PID/wchan.
583	 *
584	 * This works with older implementations of procps as well.
585	 */
586	if (wchan)
587		seq_puts(m, " 1");
588	else
589		seq_puts(m, " 0");
590
591	seq_put_decimal_ull(m, " ", 0);
592	seq_put_decimal_ull(m, " ", 0);
593	seq_put_decimal_ll(m, " ", task->exit_signal);
594	seq_put_decimal_ll(m, " ", task_cpu(task));
595	seq_put_decimal_ull(m, " ", task->rt_priority);
596	seq_put_decimal_ull(m, " ", task->policy);
597	seq_put_decimal_ull(m, " ", delayacct_blkio_ticks(task));
598	seq_put_decimal_ull(m, " ", nsec_to_clock_t(gtime));
599	seq_put_decimal_ll(m, " ", nsec_to_clock_t(cgtime));
600
601	if (mm && permitted) {
602		seq_put_decimal_ull(m, " ", mm->start_data);
603		seq_put_decimal_ull(m, " ", mm->end_data);
604		seq_put_decimal_ull(m, " ", mm->start_brk);
605		seq_put_decimal_ull(m, " ", mm->arg_start);
606		seq_put_decimal_ull(m, " ", mm->arg_end);
607		seq_put_decimal_ull(m, " ", mm->env_start);
608		seq_put_decimal_ull(m, " ", mm->env_end);
609	} else
610		seq_puts(m, " 0 0 0 0 0 0 0");
611
612	if (permitted)
613		seq_put_decimal_ll(m, " ", task->exit_code);
614	else
615		seq_puts(m, " 0");
616
617	seq_putc(m, '\n');
618	if (mm)
619		mmput(mm);
620	return 0;
621}
622
623int proc_tid_stat(struct seq_file *m, struct pid_namespace *ns,
624			struct pid *pid, struct task_struct *task)
625{
626	return do_task_stat(m, ns, pid, task, 0);
627}
628
629int proc_tgid_stat(struct seq_file *m, struct pid_namespace *ns,
630			struct pid *pid, struct task_struct *task)
631{
632	return do_task_stat(m, ns, pid, task, 1);
633}
634
635int proc_pid_statm(struct seq_file *m, struct pid_namespace *ns,
636			struct pid *pid, struct task_struct *task)
637{
638	unsigned long size = 0, resident = 0, shared = 0, text = 0, data = 0;
639	struct mm_struct *mm = get_task_mm(task);
640
641	if (mm) {
642		size = task_statm(mm, &shared, &text, &data, &resident);
643		mmput(mm);
644	}
645	/*
646	 * For quick read, open code by putting numbers directly
647	 * expected format is
648	 * seq_printf(m, "%lu %lu %lu %lu 0 %lu 0\n",
649	 *               size, resident, shared, text, data);
650	 */
651	seq_put_decimal_ull(m, "", size);
652	seq_put_decimal_ull(m, " ", resident);
653	seq_put_decimal_ull(m, " ", shared);
654	seq_put_decimal_ull(m, " ", text);
655	seq_put_decimal_ull(m, " ", 0);
656	seq_put_decimal_ull(m, " ", data);
657	seq_put_decimal_ull(m, " ", 0);
658	seq_putc(m, '\n');
659
660	return 0;
661}
662
663#ifdef CONFIG_PROC_CHILDREN
664static struct pid *
665get_children_pid(struct inode *inode, struct pid *pid_prev, loff_t pos)
666{
667	struct task_struct *start, *task;
668	struct pid *pid = NULL;
669
670	read_lock(&tasklist_lock);
671
672	start = pid_task(proc_pid(inode), PIDTYPE_PID);
673	if (!start)
674		goto out;
675
676	/*
677	 * Lets try to continue searching first, this gives
678	 * us significant speedup on children-rich processes.
679	 */
680	if (pid_prev) {
681		task = pid_task(pid_prev, PIDTYPE_PID);
682		if (task && task->real_parent == start &&
683		    !(list_empty(&task->sibling))) {
684			if (list_is_last(&task->sibling, &start->children))
685				goto out;
686			task = list_first_entry(&task->sibling,
687						struct task_struct, sibling);
688			pid = get_pid(task_pid(task));
689			goto out;
690		}
691	}
692
693	/*
694	 * Slow search case.
695	 *
696	 * We might miss some children here if children
697	 * are exited while we were not holding the lock,
698	 * but it was never promised to be accurate that
699	 * much.
700	 *
701	 * "Just suppose that the parent sleeps, but N children
702	 *  exit after we printed their tids. Now the slow paths
703	 *  skips N extra children, we miss N tasks." (c)
704	 *
705	 * So one need to stop or freeze the leader and all
706	 * its children to get a precise result.
707	 */
708	list_for_each_entry(task, &start->children, sibling) {
709		if (pos-- == 0) {
710			pid = get_pid(task_pid(task));
711			break;
712		}
713	}
714
715out:
716	read_unlock(&tasklist_lock);
717	return pid;
718}
719
720static int children_seq_show(struct seq_file *seq, void *v)
721{
722	struct inode *inode = file_inode(seq->file);
723
724	seq_printf(seq, "%d ", pid_nr_ns(v, proc_pid_ns(inode)));
725	return 0;
726}
727
728static void *children_seq_start(struct seq_file *seq, loff_t *pos)
729{
730	return get_children_pid(file_inode(seq->file), NULL, *pos);
731}
732
733static void *children_seq_next(struct seq_file *seq, void *v, loff_t *pos)
734{
735	struct pid *pid;
736
737	pid = get_children_pid(file_inode(seq->file), v, *pos + 1);
738	put_pid(v);
739
740	++*pos;
741	return pid;
742}
743
744static void children_seq_stop(struct seq_file *seq, void *v)
745{
746	put_pid(v);
747}
748
749static const struct seq_operations children_seq_ops = {
750	.start	= children_seq_start,
751	.next	= children_seq_next,
752	.stop	= children_seq_stop,
753	.show	= children_seq_show,
754};
755
756static int children_seq_open(struct inode *inode, struct file *file)
757{
758	return seq_open(file, &children_seq_ops);
759}
760
761const struct file_operations proc_tid_children_operations = {
762	.open    = children_seq_open,
763	.read    = seq_read,
764	.llseek  = seq_lseek,
765	.release = seq_release,
766};
767#endif /* CONFIG_PROC_CHILDREN */