// SPDX-License-Identifier: GPL-2.0

  /*
   *  linux/fs/proc/array.c
   *
   *  Copyright (C) 1992  by Linus Torvalds
   *  based on ideas by Darren Senn
   *
   * Fixes:
   * Michael. K. Johnson: stat,statm extensions.
   *                      <johnsonm@stolaf.edu>
   *
   * Pauline Middelink :  Made cmdline,envline only break at '\0's, to
   *                      make sure SET_PROCTITLE works. Also removed
   *                      bad '!' which forced address recalculation for
   *                      EVERY character on the current page.
   *                      <middelin@polyware.iaf.nl>
   *
   * Danny ter Haar    :	added cpuinfo
   *			<dth@cistron.nl>
   *
   * Alessandro Rubini :  profile extension.
   *                      <rubini@ipvvis.unipv.it>
   *
   * Jeff Tranter      :  added BogoMips field to cpuinfo
   *                      <Jeff_Tranter@Mitel.COM>
   *
   * Bruno Haible      :  remove 4K limit for the maps file
   *			<haible@ma2s2.mathematik.uni-karlsruhe.de>
   *
   * Yves Arrouye      :  remove removal of trailing spaces in get_array.
   *			<Yves.Arrouye@marin.fdn.fr>
   *
   * Jerome Forissier  :  added per-CPU time information to /proc/stat
   *                      and /proc/<pid>/cpu extension
   *                      <forissier@isia.cma.fr>
   *			- Incorporation and non-SMP safe operation
   *			of forissier patch in 2.1.78 by
   *			Hans Marcus <crowbar@concepts.nl>
   *
   * aeb@cwi.nl        :  /proc/partitions
   *
   *
   * Alan Cox	     :  security fixes.

   *			<alan@lxorguk.ukuu.org.uk>

   *
   * Al Viro           :  safe handling of mm_struct
   *
   * Gerhard Wichert   :  added BIGMEM support
   * Siemens AG           <Gerhard.Wichert@pdb.siemens.de>
   *
   * Al Viro & Jeff Garzik :  moved most of the thing into base.c and
   *			 :  proc_misc.c. The rest may eventually go into
   *			 :  base.c too.
   */

  #include <linux/types.h>
  #include <linux/errno.h>
  #include <linux/time.h>
  #include <linux/kernel.h>
  #include <linux/kernel_stat.h>
  #include <linux/tty.h>
  #include <linux/string.h>
  #include <linux/mman.h>

  #include <linux/sched/mm.h>

  #include <linux/sched/numa_balancing.h>

  #include <linux/sched/task_stack.h>

  #include <linux/sched/task.h>

  #include <linux/sched/cputime.h>

  #include <linux/proc_fs.h>
  #include <linux/ioport.h>

  #include <linux/uaccess.h>
  #include <linux/io.h>

  #include <linux/mm.h>
  #include <linux/hugetlb.h>
  #include <linux/pagemap.h>
  #include <linux/swap.h>

  #include <linux/smp.h>
  #include <linux/signal.h>
  #include <linux/highmem.h>
  #include <linux/file.h>

  #include <linux/fdtable.h>

  #include <linux/times.h>
  #include <linux/cpuset.h>

  #include <linux/rcupdate.h>

  #include <linux/delayacct.h>

  #include <linux/seq_file.h>

  #include <linux/pid_namespace.h>

  #include <linux/prctl.h>

  #include <linux/ptrace.h>

  #include <linux/tracehook.h>

  #include <linux/string_helpers.h>

  #include <linux/user_namespace.h>

  #include <linux/fs_struct.h>

  #include <asm/processor.h>
  #include "internal.h"

  void proc_task_name(struct seq_file *m, struct task_struct *p, bool escape)

  {

  	char *buf;

  	size_t size;

  	char tcomm[64];

  	int ret;

  	if (p->flags & PF_WQ_WORKER)
  		wq_worker_comm(tcomm, sizeof(tcomm), p);
  	else
  		__get_task_comm(tcomm, sizeof(tcomm), p);

  	size = seq_get_buf(m, &buf);

  	if (escape) {
  		ret = string_escape_str(tcomm, buf, size,
  					ESCAPE_SPACE | ESCAPE_SPECIAL, "
  \\");
  		if (ret >= size)
  			ret = -1;
  	} else {
  		ret = strscpy(buf, tcomm, size);
  	}

  	seq_commit(m, ret);

  }
  
  /*
   * The task state array is a strange "bitmap" of
   * reasons to sleep. Thus "running" is zero, and
   * you can test for combinations of others with
   * simple bit tests.
   */

  static const char * const task_state_array[] = {

  
  	/* states in TASK_REPORT: */
  	"R (running)",		/* 0x00 */
  	"S (sleeping)",		/* 0x01 */
  	"D (disk sleep)",	/* 0x02 */
  	"T (stopped)",		/* 0x04 */
  	"t (tracing stop)",	/* 0x08 */
  	"X (dead)",		/* 0x10 */
  	"Z (zombie)",		/* 0x20 */

  	"P (parked)",		/* 0x40 */

  
  	/* states beyond TASK_REPORT: */

  	"I (idle)",		/* 0x80 */

  };

  static inline const char *get_task_state(struct task_struct *tsk)

  {

  	BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != ARRAY_SIZE(task_state_array));

  	return task_state_array[task_state_index(tsk)];

  }

  static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
  				struct pid *pid, struct task_struct *p)

  {

  	struct user_namespace *user_ns = seq_user_ns(m);

  	struct group_info *group_info;

  	int g, umask = -1;

  	struct task_struct *tracer;

  	const struct cred *cred;

  	pid_t ppid, tpid = 0, tgid, ngid;

  	unsigned int max_fds = 0;

  	rcu_read_lock();

  	ppid = pid_alive(p) ?
  		task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0;

  
  	tracer = ptrace_parent(p);
  	if (tracer)
  		tpid = task_pid_nr_ns(tracer, ns);

  
  	tgid = task_tgid_nr_ns(p, ns);
  	ngid = task_numa_group_id(p);

  	cred = get_task_cred(p);

  
  	task_lock(p);

  	if (p->fs)
  		umask = p->fs->umask;

  	if (p->files)
  		max_fds = files_fdtable(p->files)->max_fds;
  	task_unlock(p);

  	rcu_read_unlock();

  	if (umask >= 0)
  		seq_printf(m, "Umask:\t%#04o
  ", umask);

  	seq_puts(m, "State:\t");
  	seq_puts(m, get_task_state(p));

  	seq_put_decimal_ull(m, "
  Tgid:\t", tgid);
  	seq_put_decimal_ull(m, "
  Ngid:\t", ngid);
  	seq_put_decimal_ull(m, "
  Pid:\t", pid_nr_ns(pid, ns));
  	seq_put_decimal_ull(m, "
  PPid:\t", ppid);
  	seq_put_decimal_ull(m, "
  TracerPid:\t", tpid);
  	seq_put_decimal_ull(m, "
  Uid:\t", from_kuid_munged(user_ns, cred->uid));
  	seq_put_decimal_ull(m, "\t", from_kuid_munged(user_ns, cred->euid));
  	seq_put_decimal_ull(m, "\t", from_kuid_munged(user_ns, cred->suid));
  	seq_put_decimal_ull(m, "\t", from_kuid_munged(user_ns, cred->fsuid));
  	seq_put_decimal_ull(m, "
  Gid:\t", from_kgid_munged(user_ns, cred->gid));
  	seq_put_decimal_ull(m, "\t", from_kgid_munged(user_ns, cred->egid));
  	seq_put_decimal_ull(m, "\t", from_kgid_munged(user_ns, cred->sgid));
  	seq_put_decimal_ull(m, "\t", from_kgid_munged(user_ns, cred->fsgid));
  	seq_put_decimal_ull(m, "
  FDSize:\t", max_fds);

  
  	seq_puts(m, "
  Groups:\t");

  	group_info = cred->group_info;

  	for (g = 0; g < group_info->ngroups; g++)

  		seq_put_decimal_ull(m, g ? " " : "",

  				from_kgid_munged(user_ns, group_info->gid[g]));

  	put_cred(cred);

  	/* Trailing space shouldn't have been added in the first place. */
  	seq_putc(m, ' ');

  #ifdef CONFIG_PID_NS
  	seq_puts(m, "
  NStgid:");
  	for (g = ns->level; g <= pid->level; g++)

  		seq_put_decimal_ull(m, "\t", task_tgid_nr_ns(p, pid->numbers[g].ns));

  	seq_puts(m, "
  NSpid:");
  	for (g = ns->level; g <= pid->level; g++)

  		seq_put_decimal_ull(m, "\t", task_pid_nr_ns(p, pid->numbers[g].ns));

  	seq_puts(m, "
  NSpgid:");
  	for (g = ns->level; g <= pid->level; g++)

  		seq_put_decimal_ull(m, "\t", task_pgrp_nr_ns(p, pid->numbers[g].ns));

  	seq_puts(m, "
  NSsid:");
  	for (g = ns->level; g <= pid->level; g++)

  		seq_put_decimal_ull(m, "\t", task_session_nr_ns(p, pid->numbers[g].ns));

  #endif

  	seq_putc(m, '
  ');

  }

  void render_sigset_t(struct seq_file *m, const char *header,

  				sigset_t *set)

  {

  	int i;

  	seq_puts(m, header);

  
  	i = _NSIG;
  	do {
  		int x = 0;
  
  		i -= 4;
  		if (sigismember(set, i+1)) x |= 1;
  		if (sigismember(set, i+2)) x |= 2;
  		if (sigismember(set, i+3)) x |= 4;
  		if (sigismember(set, i+4)) x |= 8;

  		seq_putc(m, hex_asc[x]);

  	} while (i >= 4);

  	seq_putc(m, '
  ');

  }

  static void collect_sigign_sigcatch(struct task_struct *p, sigset_t *sigign,
  				    sigset_t *sigcatch)

  {
  	struct k_sigaction *k;
  	int i;
  
  	k = p->sighand->action;
  	for (i = 1; i <= _NSIG; ++i, ++k) {
  		if (k->sa.sa_handler == SIG_IGN)

  			sigaddset(sigign, i);

  		else if (k->sa.sa_handler != SIG_DFL)

  			sigaddset(sigcatch, i);

  	}
  }

  static inline void task_sig(struct seq_file *m, struct task_struct *p)

  {

  	unsigned long flags;

  	sigset_t pending, shpending, blocked, ignored, caught;
  	int num_threads = 0;

  	unsigned int qsize = 0;

  	unsigned long qlim = 0;
  
  	sigemptyset(&pending);
  	sigemptyset(&shpending);
  	sigemptyset(&blocked);
  	sigemptyset(&ignored);
  	sigemptyset(&caught);

  	if (lock_task_sighand(p, &flags)) {

  		pending = p->pending.signal;
  		shpending = p->signal->shared_pending.signal;
  		blocked = p->blocked;
  		collect_sigign_sigcatch(p, &ignored, &caught);

  		num_threads = get_nr_threads(p);

  		rcu_read_lock();  /* FIXME: is this correct? */

  		qsize = atomic_read(&__task_cred(p)->user->sigpending);

  		rcu_read_unlock();

  		qlim = task_rlimit(p, RLIMIT_SIGPENDING);

  		unlock_task_sighand(p, &flags);

  	}

  	seq_put_decimal_ull(m, "Threads:\t", num_threads);
  	seq_put_decimal_ull(m, "
  SigQ:\t", qsize);
  	seq_put_decimal_ull(m, "/", qlim);

  
  	/* render them all */

  	render_sigset_t(m, "
  SigPnd:\t", &pending);

  	render_sigset_t(m, "ShdPnd:\t", &shpending);
  	render_sigset_t(m, "SigBlk:\t", &blocked);
  	render_sigset_t(m, "SigIgn:\t", &ignored);
  	render_sigset_t(m, "SigCgt:\t", &caught);

  }

  static void render_cap_t(struct seq_file *m, const char *header,
  			kernel_cap_t *a)

  {
  	unsigned __capi;

  	seq_puts(m, header);

  	CAP_FOR_EACH_U32(__capi) {

  		seq_put_hex_ll(m, NULL,
  			   a->cap[CAP_LAST_U32 - __capi], 8);

  	}

  	seq_putc(m, '
  ');

  }

  static inline void task_cap(struct seq_file *m, struct task_struct *p)

  {

  	const struct cred *cred;

  	kernel_cap_t cap_inheritable, cap_permitted, cap_effective,
  			cap_bset, cap_ambient;

  	rcu_read_lock();
  	cred = __task_cred(p);
  	cap_inheritable	= cred->cap_inheritable;
  	cap_permitted	= cred->cap_permitted;
  	cap_effective	= cred->cap_effective;
  	cap_bset	= cred->cap_bset;

  	cap_ambient	= cred->cap_ambient;

  	rcu_read_unlock();
  
  	render_cap_t(m, "CapInh:\t", &cap_inheritable);
  	render_cap_t(m, "CapPrm:\t", &cap_permitted);
  	render_cap_t(m, "CapEff:\t", &cap_effective);
  	render_cap_t(m, "CapBnd:\t", &cap_bset);

  	render_cap_t(m, "CapAmb:\t", &cap_ambient);

  }

  static inline void task_seccomp(struct seq_file *m, struct task_struct *p)
  {

  	seq_put_decimal_ull(m, "NoNewPrivs:\t", task_no_new_privs(p));

  #ifdef CONFIG_SECCOMP

  	seq_put_decimal_ull(m, "
  Seccomp:\t", p->seccomp.mode);

  	seq_put_decimal_ull(m, "
  Seccomp_filters:\t",
  			    atomic_read(&p->seccomp.filter_count));

  #endif

  	seq_puts(m, "
  Speculation_Store_Bypass:\t");

  	switch (arch_prctl_spec_ctrl_get(p, PR_SPEC_STORE_BYPASS)) {
  	case -EINVAL:

  		seq_puts(m, "unknown");

  		break;
  	case PR_SPEC_NOT_AFFECTED:

  		seq_puts(m, "not vulnerable");

  		break;

  	case PR_SPEC_PRCTL | PR_SPEC_FORCE_DISABLE:

  		seq_puts(m, "thread force mitigated");

  		break;

  	case PR_SPEC_PRCTL | PR_SPEC_DISABLE:

  		seq_puts(m, "thread mitigated");

  		break;
  	case PR_SPEC_PRCTL | PR_SPEC_ENABLE:

  		seq_puts(m, "thread vulnerable");

  		break;
  	case PR_SPEC_DISABLE:

  		seq_puts(m, "globally mitigated");

  		break;
  	default:

  		seq_puts(m, "vulnerable");

  		break;
  	}

  	seq_putc(m, '
  ');

  }

  static inline void task_context_switch_counts(struct seq_file *m,
  						struct task_struct *p)

  {

  	seq_put_decimal_ull(m, "voluntary_ctxt_switches:\t", p->nvcsw);
  	seq_put_decimal_ull(m, "
  nonvoluntary_ctxt_switches:\t", p->nivcsw);

  	seq_putc(m, '
  ');

  }

  static void task_cpus_allowed(struct seq_file *m, struct task_struct *task)
  {

  	seq_printf(m, "Cpus_allowed:\t%*pb
  ",

  		   cpumask_pr_args(task->cpus_ptr));

  	seq_printf(m, "Cpus_allowed_list:\t%*pbl
  ",

  		   cpumask_pr_args(task->cpus_ptr));

  }

  static inline void task_core_dumping(struct seq_file *m, struct mm_struct *mm)
  {

  	seq_put_decimal_ull(m, "CoreDumping:\t", !!mm->core_state);
  	seq_putc(m, '
  ');

  }

  static inline void task_thp_status(struct seq_file *m, struct mm_struct *mm)
  {
  	bool thp_enabled = IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE);
  
  	if (thp_enabled)
  		thp_enabled = !test_bit(MMF_DISABLE_THP, &mm->flags);
  	seq_printf(m, "THP_enabled:\t%d
  ", thp_enabled);
  }

  int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
  			struct pid *pid, struct task_struct *task)

  {

  	struct mm_struct *mm = get_task_mm(task);

  	seq_puts(m, "Name:\t");
  	proc_task_name(m, task, true);
  	seq_putc(m, '
  ');

  	task_state(m, ns, pid, task);

  	if (mm) {

  		task_mem(m, mm);

  		task_core_dumping(m, mm);

  		task_thp_status(m, mm);

  		mmput(mm);
  	}

  	task_sig(m, task);
  	task_cap(m, task);

  	task_seccomp(m, task);

  	task_cpus_allowed(m, task);

  	cpuset_task_status_allowed(m, task);

  	task_context_switch_counts(m, task);
  	return 0;

  }

  static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
  			struct pid *pid, struct task_struct *task, int whole)

  {

  	unsigned long vsize, eip, esp, wchan = 0;

  	int priority, nice;

  	int tty_pgrp = -1, tty_nr = 0;
  	sigset_t sigign, sigcatch;
  	char state;

  	pid_t ppid = 0, pgid = -1, sid = -1;

  	int num_threads = 0;

  	int permitted;

  	struct mm_struct *mm;
  	unsigned long long start_time;
  	unsigned long cmin_flt = 0, cmaj_flt = 0;
  	unsigned long  min_flt = 0,  maj_flt = 0;

  	u64 cutime, cstime, utime, stime;

  	u64 cgtime, gtime;

  	unsigned long rsslim = 0;

  	unsigned long flags;

  
  	state = *get_task_state(task);
  	vsize = eip = esp = 0;

  	permitted = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS | PTRACE_MODE_NOAUDIT);

  	mm = get_task_mm(task);
  	if (mm) {
  		vsize = task_vsize(mm);

  		/*
  		 * esp and eip are intentionally zeroed out.  There is no
  		 * non-racy way to read them without freezing the task.
  		 * Programs that need reliable values can use ptrace(2).

  		 *
  		 * The only exception is if the task is core dumping because
  		 * a program is not able to use ptrace(2) in that case. It is
  		 * safe because the task has stopped executing permanently.

  		 */

  		if (permitted && (task->flags & (PF_EXITING|PF_DUMPCORE))) {

  			if (try_get_task_stack(task)) {
  				eip = KSTK_EIP(task);
  				esp = KSTK_ESP(task);
  				put_task_stack(task);
  			}

  		}

  	}

  	sigemptyset(&sigign);
  	sigemptyset(&sigcatch);

  	cutime = cstime = utime = stime = 0;
  	cgtime = gtime = 0;

  	if (lock_task_sighand(task, &flags)) {
  		struct signal_struct *sig = task->signal;

  
  		if (sig->tty) {

  			struct pid *pgrp = tty_get_pgrp(sig->tty);
  			tty_pgrp = pid_nr_ns(pgrp, ns);
  			put_pid(pgrp);

  			tty_nr = new_encode_dev(tty_devnum(sig->tty));

  		}

  		num_threads = get_nr_threads(task);

  		collect_sigign_sigcatch(task, &sigign, &sigcatch);

  		cmin_flt = sig->cmin_flt;
  		cmaj_flt = sig->cmaj_flt;
  		cutime = sig->cutime;
  		cstime = sig->cstime;

  		cgtime = sig->cgtime;

  		rsslim = READ_ONCE(sig->rlim[RLIMIT_RSS].rlim_cur);

  		/* add up live thread stats at the group level */
  		if (whole) {

  			struct task_struct *t = task;

  			do {
  				min_flt += t->min_flt;
  				maj_flt += t->maj_flt;

  				gtime += task_gtime(t);

  			} while_each_thread(task, t);

  			min_flt += sig->min_flt;
  			maj_flt += sig->maj_flt;

  			thread_group_cputime_adjusted(task, &utime, &stime);

  			gtime += sig->gtime;

  		}

  		sid = task_session_nr_ns(task, ns);

  		ppid = task_tgid_nr_ns(task->real_parent, ns);

  		pgid = task_pgrp_nr_ns(task, ns);

  
  		unlock_task_sighand(task, &flags);

  	}

  	if (permitted && (!whole || num_threads < 2))

  		wchan = get_wchan(task);
  	if (!whole) {
  		min_flt = task->min_flt;
  		maj_flt = task->maj_flt;

  		task_cputime_adjusted(task, &utime, &stime);

  		gtime = task_gtime(task);

  	}
  
  	/* scale priority and nice values from timeslices to -20..20 */
  	/* to make it look like a "normal" Unix priority/nice value  */
  	priority = task_prio(task);
  	nice = task_nice(task);

  	/* convert nsec -> ticks */

  	start_time = nsec_to_clock_t(task->start_boottime);

  	seq_put_decimal_ull(m, "", pid_nr_ns(pid, ns));
  	seq_puts(m, " (");

  	proc_task_name(m, task, false);

  	seq_puts(m, ") ");
  	seq_putc(m, state);

  	seq_put_decimal_ll(m, " ", ppid);
  	seq_put_decimal_ll(m, " ", pgid);
  	seq_put_decimal_ll(m, " ", sid);
  	seq_put_decimal_ll(m, " ", tty_nr);
  	seq_put_decimal_ll(m, " ", tty_pgrp);
  	seq_put_decimal_ull(m, " ", task->flags);
  	seq_put_decimal_ull(m, " ", min_flt);
  	seq_put_decimal_ull(m, " ", cmin_flt);
  	seq_put_decimal_ull(m, " ", maj_flt);
  	seq_put_decimal_ull(m, " ", cmaj_flt);

  	seq_put_decimal_ull(m, " ", nsec_to_clock_t(utime));
  	seq_put_decimal_ull(m, " ", nsec_to_clock_t(stime));
  	seq_put_decimal_ll(m, " ", nsec_to_clock_t(cutime));
  	seq_put_decimal_ll(m, " ", nsec_to_clock_t(cstime));

  	seq_put_decimal_ll(m, " ", priority);
  	seq_put_decimal_ll(m, " ", nice);
  	seq_put_decimal_ll(m, " ", num_threads);
  	seq_put_decimal_ull(m, " ", 0);
  	seq_put_decimal_ull(m, " ", start_time);
  	seq_put_decimal_ull(m, " ", vsize);
  	seq_put_decimal_ull(m, " ", mm ? get_mm_rss(mm) : 0);
  	seq_put_decimal_ull(m, " ", rsslim);
  	seq_put_decimal_ull(m, " ", mm ? (permitted ? mm->start_code : 1) : 0);
  	seq_put_decimal_ull(m, " ", mm ? (permitted ? mm->end_code : 1) : 0);
  	seq_put_decimal_ull(m, " ", (permitted && mm) ? mm->start_stack : 0);
  	seq_put_decimal_ull(m, " ", esp);
  	seq_put_decimal_ull(m, " ", eip);

  	/* The signal information here is obsolete.
  	 * It must be decimal for Linux 2.0 compatibility.
  	 * Use /proc/#/status for real-time signals.
  	 */

  	seq_put_decimal_ull(m, " ", task->pending.signal.sig[0] & 0x7fffffffUL);
  	seq_put_decimal_ull(m, " ", task->blocked.sig[0] & 0x7fffffffUL);
  	seq_put_decimal_ull(m, " ", sigign.sig[0] & 0x7fffffffUL);
  	seq_put_decimal_ull(m, " ", sigcatch.sig[0] & 0x7fffffffUL);

  
  	/*
  	 * We used to output the absolute kernel address, but that's an
  	 * information leak - so instead we show a 0/1 flag here, to signal
  	 * to user-space whether there's a wchan field in /proc/PID/wchan.
  	 *
  	 * This works with older implementations of procps as well.
  	 */
  	if (wchan)
  		seq_puts(m, " 1");
  	else
  		seq_puts(m, " 0");

  	seq_put_decimal_ull(m, " ", 0);
  	seq_put_decimal_ull(m, " ", 0);
  	seq_put_decimal_ll(m, " ", task->exit_signal);
  	seq_put_decimal_ll(m, " ", task_cpu(task));
  	seq_put_decimal_ull(m, " ", task->rt_priority);
  	seq_put_decimal_ull(m, " ", task->policy);
  	seq_put_decimal_ull(m, " ", delayacct_blkio_ticks(task));

  	seq_put_decimal_ull(m, " ", nsec_to_clock_t(gtime));
  	seq_put_decimal_ll(m, " ", nsec_to_clock_t(cgtime));

  
  	if (mm && permitted) {

  		seq_put_decimal_ull(m, " ", mm->start_data);
  		seq_put_decimal_ull(m, " ", mm->end_data);
  		seq_put_decimal_ull(m, " ", mm->start_brk);
  		seq_put_decimal_ull(m, " ", mm->arg_start);
  		seq_put_decimal_ull(m, " ", mm->arg_end);
  		seq_put_decimal_ull(m, " ", mm->env_start);
  		seq_put_decimal_ull(m, " ", mm->env_end);

  	} else

  		seq_puts(m, " 0 0 0 0 0 0 0");

  
  	if (permitted)

  		seq_put_decimal_ll(m, " ", task->exit_code);

  	else

  		seq_puts(m, " 0");

  	seq_putc(m, '
  ');

  	if (mm)

  		mmput(mm);

  	return 0;

  }

  int proc_tid_stat(struct seq_file *m, struct pid_namespace *ns,
  			struct pid *pid, struct task_struct *task)

  {

  	return do_task_stat(m, ns, pid, task, 0);

  }

  int proc_tgid_stat(struct seq_file *m, struct pid_namespace *ns,
  			struct pid *pid, struct task_struct *task)

  {

  	return do_task_stat(m, ns, pid, task, 1);

  }

  int proc_pid_statm(struct seq_file *m, struct pid_namespace *ns,
  			struct pid *pid, struct task_struct *task)

  {

  	struct mm_struct *mm = get_task_mm(task);

  	if (mm) {

  		unsigned long size;
  		unsigned long resident = 0;
  		unsigned long shared = 0;
  		unsigned long text = 0;
  		unsigned long data = 0;

  		size = task_statm(mm, &shared, &text, &data, &resident);
  		mmput(mm);

  		/*
  		 * For quick read, open code by putting numbers directly
  		 * expected format is
  		 * seq_printf(m, "%lu %lu %lu %lu 0 %lu 0
  ",
  		 *               size, resident, shared, text, data);
  		 */
  		seq_put_decimal_ull(m, "", size);
  		seq_put_decimal_ull(m, " ", resident);
  		seq_put_decimal_ull(m, " ", shared);
  		seq_put_decimal_ull(m, " ", text);
  		seq_put_decimal_ull(m, " ", 0);
  		seq_put_decimal_ull(m, " ", data);
  		seq_put_decimal_ull(m, " ", 0);
  		seq_putc(m, '
  ');
  	} else {
  		seq_write(m, "0 0 0 0 0 0 0
  ", 14);
  	}

  	return 0;

  }

  #ifdef CONFIG_PROC_CHILDREN

  static struct pid *
  get_children_pid(struct inode *inode, struct pid *pid_prev, loff_t pos)
  {
  	struct task_struct *start, *task;
  	struct pid *pid = NULL;
  
  	read_lock(&tasklist_lock);
  
  	start = pid_task(proc_pid(inode), PIDTYPE_PID);
  	if (!start)
  		goto out;
  
  	/*
  	 * Lets try to continue searching first, this gives
  	 * us significant speedup on children-rich processes.
  	 */
  	if (pid_prev) {
  		task = pid_task(pid_prev, PIDTYPE_PID);
  		if (task && task->real_parent == start &&
  		    !(list_empty(&task->sibling))) {
  			if (list_is_last(&task->sibling, &start->children))
  				goto out;
  			task = list_first_entry(&task->sibling,
  						struct task_struct, sibling);
  			pid = get_pid(task_pid(task));
  			goto out;
  		}
  	}
  
  	/*
  	 * Slow search case.
  	 *
  	 * We might miss some children here if children
  	 * are exited while we were not holding the lock,
  	 * but it was never promised to be accurate that
  	 * much.
  	 *
  	 * "Just suppose that the parent sleeps, but N children
  	 *  exit after we printed their tids. Now the slow paths
  	 *  skips N extra children, we miss N tasks." (c)
  	 *
  	 * So one need to stop or freeze the leader and all
  	 * its children to get a precise result.
  	 */
  	list_for_each_entry(task, &start->children, sibling) {
  		if (pos-- == 0) {
  			pid = get_pid(task_pid(task));
  			break;
  		}
  	}
  
  out:
  	read_unlock(&tasklist_lock);
  	return pid;
  }
  
  static int children_seq_show(struct seq_file *seq, void *v)
  {

  	struct inode *inode = file_inode(seq->file);

  	seq_printf(seq, "%d ", pid_nr_ns(v, proc_pid_ns(inode->i_sb)));

  	return 0;

  }
  
  static void *children_seq_start(struct seq_file *seq, loff_t *pos)
  {

  	return get_children_pid(file_inode(seq->file), NULL, *pos);

  }
  
  static void *children_seq_next(struct seq_file *seq, void *v, loff_t *pos)
  {
  	struct pid *pid;

  	pid = get_children_pid(file_inode(seq->file), v, *pos + 1);

  	put_pid(v);
  
  	++*pos;
  	return pid;
  }
  
  static void children_seq_stop(struct seq_file *seq, void *v)
  {
  	put_pid(v);
  }
  
  static const struct seq_operations children_seq_ops = {
  	.start	= children_seq_start,
  	.next	= children_seq_next,
  	.stop	= children_seq_stop,
  	.show	= children_seq_show,
  };
  
  static int children_seq_open(struct inode *inode, struct file *file)
  {

  	return seq_open(file, &children_seq_ops);

  }

  const struct file_operations proc_tid_children_operations = {
  	.open    = children_seq_open,
  	.read    = seq_read,
  	.llseek  = seq_lseek,

  	.release = seq_release,

  };

  #endif /* CONFIG_PROC_CHILDREN */