fs/proc/array.c

   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/time_namespace.h>
  60 #include <linux/kernel.h>
  61 #include <linux/kernel_stat.h>
  62 #include <linux/tty.h>
  63 #include <linux/string.h>
  64 #include <linux/mman.h>
  65 #include <linux/sched/mm.h>
  66 #include <linux/sched/numa_balancing.h>
  67 #include <linux/sched/task_stack.h>
  68 #include <linux/sched/task.h>
  69 #include <linux/sched/cputime.h>
  70 #include <linux/proc_fs.h>
  71 #include <linux/ioport.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/string_helpers.h>
  91 #include <linux/user_namespace.h>
  92 #include <linux/fs_struct.h>
  93 #include <linux/kthread.h>
  94
  95 #include <asm/processor.h>
  96 #include "internal.h"
  97
  98 void proc_task_name(struct seq_file *m, struct task_struct *p, bool escape)
  99 {
 100         char tcomm[64];
 101
 102         /*
 103          * Test before PF_KTHREAD because all workqueue worker threads are
 104          * kernel threads.
 105          */
 106         if (p->flags & PF_WQ_WORKER)
 107                 wq_worker_comm(tcomm, sizeof(tcomm), p);
 108         else if (p->flags & PF_KTHREAD)
 109                 get_kthread_comm(tcomm, sizeof(tcomm), p);
 110         else
 111                 __get_task_comm(tcomm, sizeof(tcomm), p);
 112
 113         if (escape)
 114                 seq_escape_str(m, tcomm, ESCAPE_SPACE | ESCAPE_SPECIAL, "\n\\");
 115         else
 116                 seq_printf(m, "%.64s", tcomm);
 117 }
 118
 119 /*
 120  * The task state array is a strange "bitmap" of
 121  * reasons to sleep. Thus "running" is zero, and
 122  * you can test for combinations of others with
 123  * simple bit tests.
 124  */
 125 static const char * const task_state_array[] = {
 126
 127         /* states in TASK_REPORT: */
 128         "R (running)",          /* 0x00 */
 129         "S (sleeping)",         /* 0x01 */
 130         "D (disk sleep)",       /* 0x02 */
 131         "T (stopped)",          /* 0x04 */
 132         "t (tracing stop)",     /* 0x08 */
 133         "X (dead)",             /* 0x10 */
 134         "Z (zombie)",           /* 0x20 */
 135         "P (parked)",           /* 0x40 */
 136
 137         /* states beyond TASK_REPORT: */
 138         "I (idle)",             /* 0x80 */
 139 };
 140
 141 static inline const char *get_task_state(struct task_struct *tsk)
 142 {
 143         BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != ARRAY_SIZE(task_state_array));
 144         return task_state_array[task_state_index(tsk)];
 145 }
 146
 147 static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
 148                                 struct pid *pid, struct task_struct *p)
 149 {
 150         struct user_namespace *user_ns = seq_user_ns(m);
 151         struct group_info *group_info;
 152         int g, umask = -1;
 153         struct task_struct *tracer;
 154         const struct cred *cred;
 155         pid_t ppid, tpid = 0, tgid, ngid;
 156         unsigned int max_fds = 0;
 157
 158         rcu_read_lock();
 159         ppid = pid_alive(p) ?
 160                 task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0;
 161
 162         tracer = ptrace_parent(p);
 163         if (tracer)
 164                 tpid = task_pid_nr_ns(tracer, ns);
 165
 166         tgid = task_tgid_nr_ns(p, ns);
 167         ngid = task_numa_group_id(p);
 168         cred = get_task_cred(p);
 169
 170         task_lock(p);
 171         if (p->fs)
 172                 umask = p->fs->umask;
 173         if (p->files)
 174                 max_fds = files_fdtable(p->files)->max_fds;
 175         task_unlock(p);
 176         rcu_read_unlock();
 177
 178         if (umask >= 0)
 179                 seq_printf(m, "Umask:\t%#04o\n", umask);
 180         seq_puts(m, "State:\t");
 181         seq_puts(m, get_task_state(p));
 182
 183         seq_put_decimal_ull(m, "\nTgid:\t", tgid);
 184         seq_put_decimal_ull(m, "\nNgid:\t", ngid);
 185         seq_put_decimal_ull(m, "\nPid:\t", pid_nr_ns(pid, ns));
 186         seq_put_decimal_ull(m, "\nPPid:\t", ppid);
 187         seq_put_decimal_ull(m, "\nTracerPid:\t", tpid);
 188         seq_put_decimal_ull(m, "\nUid:\t", from_kuid_munged(user_ns, cred->uid));
 189         seq_put_decimal_ull(m, "\t", from_kuid_munged(user_ns, cred->euid));
 190         seq_put_decimal_ull(m, "\t", from_kuid_munged(user_ns, cred->suid));
 191         seq_put_decimal_ull(m, "\t", from_kuid_munged(user_ns, cred->fsuid));
 192         seq_put_decimal_ull(m, "\nGid:\t", from_kgid_munged(user_ns, cred->gid));
 193         seq_put_decimal_ull(m, "\t", from_kgid_munged(user_ns, cred->egid));
 194         seq_put_decimal_ull(m, "\t", from_kgid_munged(user_ns, cred->sgid));
 195         seq_put_decimal_ull(m, "\t", from_kgid_munged(user_ns, cred->fsgid));
 196         seq_put_decimal_ull(m, "\nFDSize:\t", max_fds);
 197
 198         seq_puts(m, "\nGroups:\t");
 199         group_info = cred->group_info;
 200         for (g = 0; g < group_info->ngroups; g++)
 201                 seq_put_decimal_ull(m, g ? " " : "",
 202                                 from_kgid_munged(user_ns, group_info->gid[g]));
 203         put_cred(cred);
 204         /* Trailing space shouldn't have been added in the first place. */
 205         seq_putc(m, ' ');
 206
 207 #ifdef CONFIG_PID_NS
 208         seq_puts(m, "\nNStgid:");
 209         for (g = ns->level; g <= pid->level; g++)
 210                 seq_put_decimal_ull(m, "\t", task_tgid_nr_ns(p, pid->numbers[g].ns));
 211         seq_puts(m, "\nNSpid:");
 212         for (g = ns->level; g <= pid->level; g++)
 213                 seq_put_decimal_ull(m, "\t", task_pid_nr_ns(p, pid->numbers[g].ns));
 214         seq_puts(m, "\nNSpgid:");
 215         for (g = ns->level; g <= pid->level; g++)
 216                 seq_put_decimal_ull(m, "\t", task_pgrp_nr_ns(p, pid->numbers[g].ns));
 217         seq_puts(m, "\nNSsid:");
 218         for (g = ns->level; g <= pid->level; g++)
 219                 seq_put_decimal_ull(m, "\t", task_session_nr_ns(p, pid->numbers[g].ns));
 220 #endif
 221         seq_putc(m, '\n');
 222 }
 223
 224 void render_sigset_t(struct seq_file *m, const char *header,
 225                                 sigset_t *set)
 226 {
 227         int i;
 228
 229         seq_puts(m, header);
 230
 231         i = _NSIG;
 232         do {
 233                 int x = 0;
 234
 235                 i -= 4;
 236                 if (sigismember(set, i+1)) x |= 1;
 237                 if (sigismember(set, i+2)) x |= 2;
 238                 if (sigismember(set, i+3)) x |= 4;
 239                 if (sigismember(set, i+4)) x |= 8;
 240                 seq_putc(m, hex_asc[x]);
 241         } while (i >= 4);
 242
 243         seq_putc(m, '\n');
 244 }
 245
 246 static void collect_sigign_sigcatch(struct task_struct *p, sigset_t *sigign,
 247                                     sigset_t *sigcatch)
 248 {
 249         struct k_sigaction *k;
 250         int i;
 251
 252         k = p->sighand->action;
 253         for (i = 1; i <= _NSIG; ++i, ++k) {
 254                 if (k->sa.sa_handler == SIG_IGN)
 255                         sigaddset(sigign, i);
 256                 else if (k->sa.sa_handler != SIG_DFL)
 257                         sigaddset(sigcatch, i);
 258         }
 259 }
 260
 261 static inline void task_sig(struct seq_file *m, struct task_struct *p)
 262 {
 263         unsigned long flags;
 264         sigset_t pending, shpending, blocked, ignored, caught;
 265         int num_threads = 0;
 266         unsigned int qsize = 0;
 267         unsigned long qlim = 0;
 268
 269         sigemptyset(&pending);
 270         sigemptyset(&shpending);
 271         sigemptyset(&blocked);
 272         sigemptyset(&ignored);
 273         sigemptyset(&caught);
 274
 275         if (lock_task_sighand(p, &flags)) {
 276                 pending = p->pending.signal;
 277                 shpending = p->signal->shared_pending.signal;
 278                 blocked = p->blocked;
 279                 collect_sigign_sigcatch(p, &ignored, &caught);
 280                 num_threads = get_nr_threads(p);
 281                 rcu_read_lock();  /* FIXME: is this correct? */
 282                 qsize = get_ucounts_value(task_ucounts(p), UCOUNT_RLIMIT_SIGPENDING);
 283                 rcu_read_unlock();
 284                 qlim = task_rlimit(p, RLIMIT_SIGPENDING);
 285                 unlock_task_sighand(p, &flags);
 286         }
 287
 288         seq_put_decimal_ull(m, "Threads:\t", num_threads);
 289         seq_put_decimal_ull(m, "\nSigQ:\t", qsize);
 290         seq_put_decimal_ull(m, "/", qlim);
 291
 292         /* render them all */
 293         render_sigset_t(m, "\nSigPnd:\t", &pending);
 294         render_sigset_t(m, "ShdPnd:\t", &shpending);
 295         render_sigset_t(m, "SigBlk:\t", &blocked);
 296         render_sigset_t(m, "SigIgn:\t", &ignored);
 297         render_sigset_t(m, "SigCgt:\t", &caught);
 298 }
 299
 300 static void render_cap_t(struct seq_file *m, const char *header,
 301                         kernel_cap_t *a)
 302 {
 303         unsigned __capi;
 304
 305         seq_puts(m, header);
 306         CAP_FOR_EACH_U32(__capi) {
 307                 seq_put_hex_ll(m, NULL,
 308                            a->cap[CAP_LAST_U32 - __capi], 8);
 309         }
 310         seq_putc(m, '\n');
 311 }
 312
 313 static inline void task_cap(struct seq_file *m, struct task_struct *p)
 314 {
 315         const struct cred *cred;
 316         kernel_cap_t cap_inheritable, cap_permitted, cap_effective,
 317                         cap_bset, cap_ambient;
 318
 319         rcu_read_lock();
 320         cred = __task_cred(p);
 321         cap_inheritable = cred->cap_inheritable;
 322         cap_permitted   = cred->cap_permitted;
 323         cap_effective   = cred->cap_effective;
 324         cap_bset        = cred->cap_bset;
 325         cap_ambient     = cred->cap_ambient;
 326         rcu_read_unlock();
 327
 328         render_cap_t(m, "CapInh:\t", &cap_inheritable);
 329         render_cap_t(m, "CapPrm:\t", &cap_permitted);
 330         render_cap_t(m, "CapEff:\t", &cap_effective);
 331         render_cap_t(m, "CapBnd:\t", &cap_bset);
 332         render_cap_t(m, "CapAmb:\t", &cap_ambient);
 333 }
 334
 335 static inline void task_seccomp(struct seq_file *m, struct task_struct *p)
 336 {
 337         seq_put_decimal_ull(m, "NoNewPrivs:\t", task_no_new_privs(p));
 338 #ifdef CONFIG_SECCOMP
 339         seq_put_decimal_ull(m, "\nSeccomp:\t", p->seccomp.mode);
 340 #ifdef CONFIG_SECCOMP_FILTER
 341         seq_put_decimal_ull(m, "\nSeccomp_filters:\t",
 342                             atomic_read(&p->seccomp.filter_count));
 343 #endif
 344 #endif
 345         seq_puts(m, "\nSpeculation_Store_Bypass:\t");
 346         switch (arch_prctl_spec_ctrl_get(p, PR_SPEC_STORE_BYPASS)) {
 347         case -EINVAL:
 348                 seq_puts(m, "unknown");
 349                 break;
 350         case PR_SPEC_NOT_AFFECTED:
 351                 seq_puts(m, "not vulnerable");
 352                 break;
 353         case PR_SPEC_PRCTL | PR_SPEC_FORCE_DISABLE:
 354                 seq_puts(m, "thread force mitigated");
 355                 break;
 356         case PR_SPEC_PRCTL | PR_SPEC_DISABLE:
 357                 seq_puts(m, "thread mitigated");
 358                 break;
 359         case PR_SPEC_PRCTL | PR_SPEC_ENABLE:
 360                 seq_puts(m, "thread vulnerable");
 361                 break;
 362         case PR_SPEC_DISABLE:
 363                 seq_puts(m, "globally mitigated");
 364                 break;
 365         default:
 366                 seq_puts(m, "vulnerable");
 367                 break;
 368         }
 369
 370         seq_puts(m, "\nSpeculationIndirectBranch:\t");
 371         switch (arch_prctl_spec_ctrl_get(p, PR_SPEC_INDIRECT_BRANCH)) {
 372         case -EINVAL:
 373                 seq_puts(m, "unsupported");
 374                 break;
 375         case PR_SPEC_NOT_AFFECTED:
 376                 seq_puts(m, "not affected");
 377                 break;
 378         case PR_SPEC_PRCTL | PR_SPEC_FORCE_DISABLE:
 379                 seq_puts(m, "conditional force disabled");
 380                 break;
 381         case PR_SPEC_PRCTL | PR_SPEC_DISABLE:
 382                 seq_puts(m, "conditional disabled");
 383                 break;
 384         case PR_SPEC_PRCTL | PR_SPEC_ENABLE:
 385                 seq_puts(m, "conditional enabled");
 386                 break;
 387         case PR_SPEC_ENABLE:
 388                 seq_puts(m, "always enabled");
 389                 break;
 390         case PR_SPEC_DISABLE:
 391                 seq_puts(m, "always disabled");
 392                 break;
 393         default:
 394                 seq_puts(m, "unknown");
 395                 break;
 396         }
 397         seq_putc(m, '\n');
 398 }
 399
 400 static inline void task_context_switch_counts(struct seq_file *m,
 401                                                 struct task_struct *p)
 402 {
 403         seq_put_decimal_ull(m, "voluntary_ctxt_switches:\t", p->nvcsw);
 404         seq_put_decimal_ull(m, "\nnonvoluntary_ctxt_switches:\t", p->nivcsw);
 405         seq_putc(m, '\n');
 406 }
 407
 408 static void task_cpus_allowed(struct seq_file *m, struct task_struct *task)
 409 {
 410         seq_printf(m, "Cpus_allowed:\t%*pb\n",
 411                    cpumask_pr_args(&task->cpus_mask));
 412         seq_printf(m, "Cpus_allowed_list:\t%*pbl\n",
 413                    cpumask_pr_args(&task->cpus_mask));
 414 }
 415
 416 static inline void task_core_dumping(struct seq_file *m, struct task_struct *task)
 417 {
 418         seq_put_decimal_ull(m, "CoreDumping:\t", !!task->signal->core_state);
 419         seq_putc(m, '\n');
 420 }
 421
 422 static inline void task_thp_status(struct seq_file *m, struct mm_struct *mm)
 423 {
 424         bool thp_enabled = IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE);
 425
 426         if (thp_enabled)
 427                 thp_enabled = !test_bit(MMF_DISABLE_THP, &mm->flags);
 428         seq_printf(m, "THP_enabled:\t%d\n", thp_enabled);
 429 }
 430
 431 int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
 432                         struct pid *pid, struct task_struct *task)
 433 {
 434         struct mm_struct *mm = get_task_mm(task);
 435
 436         seq_puts(m, "Name:\t");
 437         proc_task_name(m, task, true);
 438         seq_putc(m, '\n');
 439
 440         task_state(m, ns, pid, task);
 441
 442         if (mm) {
 443                 task_mem(m, mm);
 444                 task_core_dumping(m, task);
 445                 task_thp_status(m, mm);
 446                 mmput(mm);
 447         }
 448         task_sig(m, task);
 449         task_cap(m, task);
 450         task_seccomp(m, task);
 451         task_cpus_allowed(m, task);
 452         cpuset_task_status_allowed(m, task);
 453         task_context_switch_counts(m, task);
 454         return 0;
 455 }
 456
 457 static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
 458                         struct pid *pid, struct task_struct *task, int whole)
 459 {
 460         unsigned long vsize, eip, esp, wchan = 0;
 461         int priority, nice;
 462         int tty_pgrp = -1, tty_nr = 0;
 463         sigset_t sigign, sigcatch;
 464         char state;
 465         pid_t ppid = 0, pgid = -1, sid = -1;
 466         int num_threads = 0;
 467         int permitted;
 468         struct mm_struct *mm;
 469         unsigned long long start_time;
 470         unsigned long cmin_flt = 0, cmaj_flt = 0;
 471         unsigned long  min_flt = 0,  maj_flt = 0;
 472         u64 cutime, cstime, utime, stime;
 473         u64 cgtime, gtime;
 474         unsigned long rsslim = 0;
 475         unsigned long flags;
 476         int exit_code = task->exit_code;
 477
 478         state = *get_task_state(task);
 479         vsize = eip = esp = 0;
 480         permitted = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS | PTRACE_MODE_NOAUDIT);
 481         mm = get_task_mm(task);
 482         if (mm) {
 483                 vsize = task_vsize(mm);
 484                 /*
 485                  * esp and eip are intentionally zeroed out.  There is no
 486                  * non-racy way to read them without freezing the task.
 487                  * Programs that need reliable values can use ptrace(2).
 488                  *
 489                  * The only exception is if the task is core dumping because
 490                  * a program is not able to use ptrace(2) in that case. It is
 491                  * safe because the task has stopped executing permanently.
 492                  */
 493                 if (permitted && (task->flags & (PF_EXITING|PF_DUMPCORE))) {
 494                         if (try_get_task_stack(task)) {
 495                                 eip = KSTK_EIP(task);
 496                                 esp = KSTK_ESP(task);
 497                                 put_task_stack(task);
 498                         }
 499                 }
 500         }
 501
 502         sigemptyset(&sigign);
 503         sigemptyset(&sigcatch);
 504         cutime = cstime = utime = stime = 0;
 505         cgtime = gtime = 0;
 506
 507         if (lock_task_sighand(task, &flags)) {
 508                 struct signal_struct *sig = task->signal;
 509
 510                 if (sig->tty) {
 511                         struct pid *pgrp = tty_get_pgrp(sig->tty);
 512                         tty_pgrp = pid_nr_ns(pgrp, ns);
 513                         put_pid(pgrp);
 514                         tty_nr = new_encode_dev(tty_devnum(sig->tty));
 515                 }
 516
 517                 num_threads = get_nr_threads(task);
 518                 collect_sigign_sigcatch(task, &sigign, &sigcatch);
 519
 520                 cmin_flt = sig->cmin_flt;
 521                 cmaj_flt = sig->cmaj_flt;
 522                 cutime = sig->cutime;
 523                 cstime = sig->cstime;
 524                 cgtime = sig->cgtime;
 525                 rsslim = READ_ONCE(sig->rlim[RLIMIT_RSS].rlim_cur);
 526
 527                 /* add up live thread stats at the group level */
 528                 if (whole) {
 529                         struct task_struct *t = task;
 530                         do {
 531                                 min_flt += t->min_flt;
 532                                 maj_flt += t->maj_flt;
 533                                 gtime += task_gtime(t);
 534                         } while_each_thread(task, t);
 535
 536                         min_flt += sig->min_flt;
 537                         maj_flt += sig->maj_flt;
 538                         thread_group_cputime_adjusted(task, &utime, &stime);
 539                         gtime += sig->gtime;
 540
 541                         if (sig->flags & (SIGNAL_GROUP_EXIT | SIGNAL_STOP_STOPPED))
 542                                 exit_code = sig->group_exit_code;
 543                 }
 544
 545                 sid = task_session_nr_ns(task, ns);
 546                 ppid = task_tgid_nr_ns(task->real_parent, ns);
 547                 pgid = task_pgrp_nr_ns(task, ns);
 548
 549                 unlock_task_sighand(task, &flags);
 550         }
 551
 552         if (permitted && (!whole || num_threads < 2))
 553                 wchan = !task_is_running(task);
 554         if (!whole) {
 555                 min_flt = task->min_flt;
 556                 maj_flt = task->maj_flt;
 557                 task_cputime_adjusted(task, &utime, &stime);
 558                 gtime = task_gtime(task);
 559         }
 560
 561         /* scale priority and nice values from timeslices to -20..20 */
 562         /* to make it look like a "normal" Unix priority/nice value  */
 563         priority = task_prio(task);
 564         nice = task_nice(task);
 565
 566         /* apply timens offset for boottime and convert nsec -> ticks */
 567         start_time =
 568                 nsec_to_clock_t(timens_add_boottime_ns(task->start_boottime));
 569
 570         seq_put_decimal_ull(m, "", pid_nr_ns(pid, ns));
 571         seq_puts(m, " (");
 572         proc_task_name(m, task, false);
 573         seq_puts(m, ") ");
 574         seq_putc(m, state);
 575         seq_put_decimal_ll(m, " ", ppid);
 576         seq_put_decimal_ll(m, " ", pgid);
 577         seq_put_decimal_ll(m, " ", sid);
 578         seq_put_decimal_ll(m, " ", tty_nr);
 579         seq_put_decimal_ll(m, " ", tty_pgrp);
 580         seq_put_decimal_ull(m, " ", task->flags);
 581         seq_put_decimal_ull(m, " ", min_flt);
 582         seq_put_decimal_ull(m, " ", cmin_flt);
 583         seq_put_decimal_ull(m, " ", maj_flt);
 584         seq_put_decimal_ull(m, " ", cmaj_flt);
 585         seq_put_decimal_ull(m, " ", nsec_to_clock_t(utime));
 586         seq_put_decimal_ull(m, " ", nsec_to_clock_t(stime));
 587         seq_put_decimal_ll(m, " ", nsec_to_clock_t(cutime));
 588         seq_put_decimal_ll(m, " ", nsec_to_clock_t(cstime));
 589         seq_put_decimal_ll(m, " ", priority);
 590         seq_put_decimal_ll(m, " ", nice);
 591         seq_put_decimal_ll(m, " ", num_threads);
 592         seq_put_decimal_ull(m, " ", 0);
 593         seq_put_decimal_ull(m, " ", start_time);
 594         seq_put_decimal_ull(m, " ", vsize);
 595         seq_put_decimal_ull(m, " ", mm ? get_mm_rss(mm) : 0);
 596         seq_put_decimal_ull(m, " ", rsslim);
 597         seq_put_decimal_ull(m, " ", mm ? (permitted ? mm->start_code : 1) : 0);
 598         seq_put_decimal_ull(m, " ", mm ? (permitted ? mm->end_code : 1) : 0);
 599         seq_put_decimal_ull(m, " ", (permitted && mm) ? mm->start_stack : 0);
 600         seq_put_decimal_ull(m, " ", esp);
 601         seq_put_decimal_ull(m, " ", eip);
 602         /* The signal information here is obsolete.
 603          * It must be decimal for Linux 2.0 compatibility.
 604          * Use /proc/#/status for real-time signals.
 605          */
 606         seq_put_decimal_ull(m, " ", task->pending.signal.sig[0] & 0x7fffffffUL);
 607         seq_put_decimal_ull(m, " ", task->blocked.sig[0] & 0x7fffffffUL);
 608         seq_put_decimal_ull(m, " ", sigign.sig[0] & 0x7fffffffUL);
 609         seq_put_decimal_ull(m, " ", sigcatch.sig[0] & 0x7fffffffUL);
 610
 611         /*
 612          * We used to output the absolute kernel address, but that's an
 613          * information leak - so instead we show a 0/1 flag here, to signal
 614          * to user-space whether there's a wchan field in /proc/PID/wchan.
 615          *
 616          * This works with older implementations of procps as well.
 617          */
 618         seq_put_decimal_ull(m, " ", wchan);
 619
 620         seq_put_decimal_ull(m, " ", 0);
 621         seq_put_decimal_ull(m, " ", 0);
 622         seq_put_decimal_ll(m, " ", task->exit_signal);
 623         seq_put_decimal_ll(m, " ", task_cpu(task));
 624         seq_put_decimal_ull(m, " ", task->rt_priority);
 625         seq_put_decimal_ull(m, " ", task->policy);
 626         seq_put_decimal_ull(m, " ", delayacct_blkio_ticks(task));
 627         seq_put_decimal_ull(m, " ", nsec_to_clock_t(gtime));
 628         seq_put_decimal_ll(m, " ", nsec_to_clock_t(cgtime));
 629
 630         if (mm && permitted) {
 631                 seq_put_decimal_ull(m, " ", mm->start_data);
 632                 seq_put_decimal_ull(m, " ", mm->end_data);
 633                 seq_put_decimal_ull(m, " ", mm->start_brk);
 634                 seq_put_decimal_ull(m, " ", mm->arg_start);
 635                 seq_put_decimal_ull(m, " ", mm->arg_end);
 636                 seq_put_decimal_ull(m, " ", mm->env_start);
 637                 seq_put_decimal_ull(m, " ", mm->env_end);
 638         } else
 639                 seq_puts(m, " 0 0 0 0 0 0 0");
 640
 641         if (permitted)
 642                 seq_put_decimal_ll(m, " ", exit_code);
 643         else
 644                 seq_puts(m, " 0");
 645
 646         seq_putc(m, '\n');
 647         if (mm)
 648                 mmput(mm);
 649         return 0;
 650 }
 651
 652 int proc_tid_stat(struct seq_file *m, struct pid_namespace *ns,
 653                         struct pid *pid, struct task_struct *task)
 654 {
 655         return do_task_stat(m, ns, pid, task, 0);
 656 }
 657
 658 int proc_tgid_stat(struct seq_file *m, struct pid_namespace *ns,
 659                         struct pid *pid, struct task_struct *task)
 660 {
 661         return do_task_stat(m, ns, pid, task, 1);
 662 }
 663
 664 int proc_pid_statm(struct seq_file *m, struct pid_namespace *ns,
 665                         struct pid *pid, struct task_struct *task)
 666 {
 667         struct mm_struct *mm = get_task_mm(task);
 668
 669         if (mm) {
 670                 unsigned long size;
 671                 unsigned long resident = 0;
 672                 unsigned long shared = 0;
 673                 unsigned long text = 0;
 674                 unsigned long data = 0;
 675
 676                 size = task_statm(mm, &shared, &text, &data, &resident);
 677                 mmput(mm);
 678
 679                 /*
 680                  * For quick read, open code by putting numbers directly
 681                  * expected format is
 682                  * seq_printf(m, "%lu %lu %lu %lu 0 %lu 0\n",
 683                  *               size, resident, shared, text, data);
 684                  */
 685                 seq_put_decimal_ull(m, "", size);
 686                 seq_put_decimal_ull(m, " ", resident);
 687                 seq_put_decimal_ull(m, " ", shared);
 688                 seq_put_decimal_ull(m, " ", text);
 689                 seq_put_decimal_ull(m, " ", 0);
 690                 seq_put_decimal_ull(m, " ", data);
 691                 seq_put_decimal_ull(m, " ", 0);
 692                 seq_putc(m, '\n');
 693         } else {
 694                 seq_write(m, "0 0 0 0 0 0 0\n", 14);
 695         }
 696         return 0;
 697 }
 698
 699 #ifdef CONFIG_PROC_CHILDREN
 700 static struct pid *
 701 get_children_pid(struct inode *inode, struct pid *pid_prev, loff_t pos)
 702 {
 703         struct task_struct *start, *task;
 704         struct pid *pid = NULL;
 705
 706         read_lock(&tasklist_lock);
 707
 708         start = pid_task(proc_pid(inode), PIDTYPE_PID);
 709         if (!start)
 710                 goto out;
 711
 712         /*
 713          * Lets try to continue searching first, this gives
 714          * us significant speedup on children-rich processes.
 715          */
 716         if (pid_prev) {
 717                 task = pid_task(pid_prev, PIDTYPE_PID);
 718                 if (task && task->real_parent == start &&
 719                     !(list_empty(&task->sibling))) {
 720                         if (list_is_last(&task->sibling, &start->children))
 721                                 goto out;
 722                         task = list_first_entry(&task->sibling,
 723                                                 struct task_struct, sibling);
 724                         pid = get_pid(task_pid(task));
 725                         goto out;
 726                 }
 727         }
 728
 729         /*
 730          * Slow search case.
 731          *
 732          * We might miss some children here if children
 733          * are exited while we were not holding the lock,
 734          * but it was never promised to be accurate that
 735          * much.
 736          *
 737          * "Just suppose that the parent sleeps, but N children
 738          *  exit after we printed their tids. Now the slow paths
 739          *  skips N extra children, we miss N tasks." (c)
 740          *
 741          * So one need to stop or freeze the leader and all
 742          * its children to get a precise result.
 743          */
 744         list_for_each_entry(task, &start->children, sibling) {
 745                 if (pos-- == 0) {
 746                         pid = get_pid(task_pid(task));
 747                         break;
 748                 }
 749         }
 750
 751 out:
 752         read_unlock(&tasklist_lock);
 753         return pid;
 754 }
 755
 756 static int children_seq_show(struct seq_file *seq, void *v)
 757 {
 758         struct inode *inode = file_inode(seq->file);
 759
 760         seq_printf(seq, "%d ", pid_nr_ns(v, proc_pid_ns(inode->i_sb)));
 761         return 0;
 762 }
 763
 764 static void *children_seq_start(struct seq_file *seq, loff_t *pos)
 765 {
 766         return get_children_pid(file_inode(seq->file), NULL, *pos);
 767 }
 768
 769 static void *children_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 770 {
 771         struct pid *pid;
 772
 773         pid = get_children_pid(file_inode(seq->file), v, *pos + 1);
 774         put_pid(v);
 775
 776         ++*pos;
 777         return pid;
 778 }
 779
 780 static void children_seq_stop(struct seq_file *seq, void *v)
 781 {
 782         put_pid(v);
 783 }
 784
 785 static const struct seq_operations children_seq_ops = {
 786         .start  = children_seq_start,
 787         .next   = children_seq_next,
 788         .stop   = children_seq_stop,
 789         .show   = children_seq_show,
 790 };
 791
 792 static int children_seq_open(struct inode *inode, struct file *file)
 793 {
 794         return seq_open(file, &children_seq_ops);
 795 }
 796
 797 const struct file_operations proc_tid_children_operations = {
 798         .open    = children_seq_open,
 799         .read    = seq_read,
 800         .llseek  = seq_lseek,
 801         .release = seq_release,
 802 };
 803 #endif /* CONFIG_PROC_CHILDREN */