2005-04-16 22:20:36 +00:00
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/*
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* linux/fs/proc/array.c
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*
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* Copyright (C) 1992 by Linus Torvalds
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* based on ideas by Darren Senn
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*
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* Fixes:
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* Michael. K. Johnson: stat,statm extensions.
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* <johnsonm@stolaf.edu>
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*
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* Pauline Middelink : Made cmdline,envline only break at '\0's, to
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* make sure SET_PROCTITLE works. Also removed
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* bad '!' which forced address recalculation for
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* EVERY character on the current page.
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* <middelin@polyware.iaf.nl>
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*
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* Danny ter Haar : added cpuinfo
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* <dth@cistron.nl>
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*
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* Alessandro Rubini : profile extension.
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* <rubini@ipvvis.unipv.it>
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*
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* Jeff Tranter : added BogoMips field to cpuinfo
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* <Jeff_Tranter@Mitel.COM>
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*
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* Bruno Haible : remove 4K limit for the maps file
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* <haible@ma2s2.mathematik.uni-karlsruhe.de>
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*
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* Yves Arrouye : remove removal of trailing spaces in get_array.
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* <Yves.Arrouye@marin.fdn.fr>
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*
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* Jerome Forissier : added per-CPU time information to /proc/stat
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* and /proc/<pid>/cpu extension
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* <forissier@isia.cma.fr>
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* - Incorporation and non-SMP safe operation
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* of forissier patch in 2.1.78 by
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* Hans Marcus <crowbar@concepts.nl>
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*
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* aeb@cwi.nl : /proc/partitions
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*
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*
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* Alan Cox : security fixes.
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2008-10-27 15:19:48 +00:00
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* <alan@lxorguk.ukuu.org.uk>
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2005-04-16 22:20:36 +00:00
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*
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* Al Viro : safe handling of mm_struct
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*
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* Gerhard Wichert : added BIGMEM support
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* Siemens AG <Gerhard.Wichert@pdb.siemens.de>
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*
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* Al Viro & Jeff Garzik : moved most of the thing into base.c and
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* : proc_misc.c. The rest may eventually go into
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* : base.c too.
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*/
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#include <linux/types.h>
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#include <linux/errno.h>
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#include <linux/time.h>
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#include <linux/kernel.h>
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#include <linux/kernel_stat.h>
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#include <linux/tty.h>
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#include <linux/string.h>
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#include <linux/mman.h>
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#include <linux/proc_fs.h>
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#include <linux/ioport.h>
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2007-07-16 07:46:31 +00:00
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#include <linux/uaccess.h>
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#include <linux/io.h>
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2005-04-16 22:20:36 +00:00
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#include <linux/mm.h>
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#include <linux/hugetlb.h>
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#include <linux/pagemap.h>
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#include <linux/swap.h>
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#include <linux/smp.h>
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#include <linux/signal.h>
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#include <linux/highmem.h>
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#include <linux/file.h>
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2008-04-24 11:44:08 +00:00
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#include <linux/fdtable.h>
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2005-04-16 22:20:36 +00:00
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#include <linux/times.h>
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#include <linux/cpuset.h>
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2005-09-17 02:28:13 +00:00
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#include <linux/rcupdate.h>
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2006-07-14 07:24:43 +00:00
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#include <linux/delayacct.h>
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2008-02-08 12:18:31 +00:00
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#include <linux/seq_file.h>
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2007-10-19 06:40:14 +00:00
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#include <linux/pid_namespace.h>
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2009-05-04 18:51:14 +00:00
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#include <linux/ptrace.h>
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2008-07-26 02:45:49 +00:00
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#include <linux/tracehook.h>
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2011-11-14 23:56:38 +00:00
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#include <linux/user_namespace.h>
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2005-04-16 22:20:36 +00:00
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#include <asm/pgtable.h>
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#include <asm/processor.h>
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#include "internal.h"
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2008-02-08 12:18:33 +00:00
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static inline void task_name(struct seq_file *m, struct task_struct *p)
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2005-04-16 22:20:36 +00:00
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{
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int i;
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2008-02-08 12:18:33 +00:00
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char *buf, *end;
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2007-07-16 07:46:31 +00:00
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char *name;
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2005-04-16 22:20:36 +00:00
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char tcomm[sizeof(p->comm)];
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get_task_comm(tcomm, p);
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2011-01-13 01:00:32 +00:00
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seq_puts(m, "Name:\t");
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2008-02-08 12:18:33 +00:00
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end = m->buf + m->size;
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buf = m->buf + m->count;
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2005-04-16 22:20:36 +00:00
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name = tcomm;
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i = sizeof(tcomm);
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2008-02-08 12:18:33 +00:00
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while (i && (buf < end)) {
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2005-04-16 22:20:36 +00:00
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unsigned char c = *name;
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name++;
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i--;
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*buf = c;
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if (!c)
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break;
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if (c == '\\') {
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2008-02-08 12:18:33 +00:00
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buf++;
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if (buf < end)
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*buf++ = c;
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2005-04-16 22:20:36 +00:00
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continue;
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}
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if (c == '\n') {
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2008-02-08 12:18:33 +00:00
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*buf++ = '\\';
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if (buf < end)
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*buf++ = 'n';
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2005-04-16 22:20:36 +00:00
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continue;
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}
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buf++;
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2008-02-08 12:18:33 +00:00
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}
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m->count = buf - m->buf;
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2011-01-13 01:00:32 +00:00
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seq_putc(m, '\n');
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2005-04-16 22:20:36 +00:00
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}
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/*
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* The task state array is a strange "bitmap" of
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* reasons to sleep. Thus "running" is zero, and
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* you can test for combinations of others with
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* simple bit tests.
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*/
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2011-05-26 23:25:51 +00:00
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static const char * const task_state_array[] = {
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2009-12-17 12:16:30 +00:00
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"R (running)", /* 0 */
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"S (sleeping)", /* 1 */
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"D (disk sleep)", /* 2 */
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"T (stopped)", /* 4 */
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"t (tracing stop)", /* 8 */
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"Z (zombie)", /* 16 */
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"X (dead)", /* 32 */
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"x (dead)", /* 64 */
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2009-12-17 12:16:29 +00:00
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"K (wakekill)", /* 128 */
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"W (waking)", /* 256 */
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2013-04-09 07:33:34 +00:00
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"P (parked)", /* 512 */
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2005-04-16 22:20:36 +00:00
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};
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2007-07-16 07:46:31 +00:00
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static inline const char *get_task_state(struct task_struct *tsk)
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2005-04-16 22:20:36 +00:00
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{
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2007-12-06 16:03:36 +00:00
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unsigned int state = (tsk->state & TASK_REPORT) | tsk->exit_state;
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2011-05-26 23:25:51 +00:00
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const char * const *p = &task_state_array[0];
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2005-04-16 22:20:36 +00:00
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2009-12-17 12:16:30 +00:00
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BUILD_BUG_ON(1 + ilog2(TASK_STATE_MAX) != ARRAY_SIZE(task_state_array));
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2005-04-16 22:20:36 +00:00
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while (state) {
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p++;
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state >>= 1;
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}
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return *p;
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}
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2008-02-08 12:18:33 +00:00
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static inline void task_state(struct seq_file *m, struct pid_namespace *ns,
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struct pid *pid, struct task_struct *p)
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2005-04-16 22:20:36 +00:00
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{
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2012-08-11 19:38:26 +00:00
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struct user_namespace *user_ns = seq_user_ns(m);
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2005-04-16 22:20:36 +00:00
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struct group_info *group_info;
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int g;
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2005-09-09 20:04:10 +00:00
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struct fdtable *fdt = NULL;
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2008-11-13 23:39:19 +00:00
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const struct cred *cred;
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2007-10-19 06:40:14 +00:00
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pid_t ppid, tpid;
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2005-04-16 22:20:36 +00:00
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2006-10-02 09:18:54 +00:00
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rcu_read_lock();
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2007-10-19 06:40:14 +00:00
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ppid = pid_alive(p) ?
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task_tgid_nr_ns(rcu_dereference(p->real_parent), ns) : 0;
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2008-07-26 02:45:49 +00:00
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tpid = 0;
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if (pid_alive(p)) {
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2011-06-17 14:50:40 +00:00
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struct task_struct *tracer = ptrace_parent(p);
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2008-07-26 02:45:49 +00:00
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if (tracer)
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tpid = task_pid_nr_ns(tracer, ns);
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}
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CRED: Fix get_task_cred() and task_state() to not resurrect dead credentials
It's possible for get_task_cred() as it currently stands to 'corrupt' a set of
credentials by incrementing their usage count after their replacement by the
task being accessed.
What happens is that get_task_cred() can race with commit_creds():
TASK_1 TASK_2 RCU_CLEANER
-->get_task_cred(TASK_2)
rcu_read_lock()
__cred = __task_cred(TASK_2)
-->commit_creds()
old_cred = TASK_2->real_cred
TASK_2->real_cred = ...
put_cred(old_cred)
call_rcu(old_cred)
[__cred->usage == 0]
get_cred(__cred)
[__cred->usage == 1]
rcu_read_unlock()
-->put_cred_rcu()
[__cred->usage == 1]
panic()
However, since a tasks credentials are generally not changed very often, we can
reasonably make use of a loop involving reading the creds pointer and using
atomic_inc_not_zero() to attempt to increment it if it hasn't already hit zero.
If successful, we can safely return the credentials in the knowledge that, even
if the task we're accessing has released them, they haven't gone to the RCU
cleanup code.
We then change task_state() in procfs to use get_task_cred() rather than
calling get_cred() on the result of __task_cred(), as that suffers from the
same problem.
Without this change, a BUG_ON in __put_cred() or in put_cred_rcu() can be
tripped when it is noticed that the usage count is not zero as it ought to be,
for example:
kernel BUG at kernel/cred.c:168!
invalid opcode: 0000 [#1] SMP
last sysfs file: /sys/kernel/mm/ksm/run
CPU 0
Pid: 2436, comm: master Not tainted 2.6.33.3-85.fc13.x86_64 #1 0HR330/OptiPlex
745
RIP: 0010:[<ffffffff81069881>] [<ffffffff81069881>] __put_cred+0xc/0x45
RSP: 0018:ffff88019e7e9eb8 EFLAGS: 00010202
RAX: 0000000000000001 RBX: ffff880161514480 RCX: 00000000ffffffff
RDX: 00000000ffffffff RSI: ffff880140c690c0 RDI: ffff880140c690c0
RBP: ffff88019e7e9eb8 R08: 00000000000000d0 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000040 R12: ffff880140c690c0
R13: ffff88019e77aea0 R14: 00007fff336b0a5c R15: 0000000000000001
FS: 00007f12f50d97c0(0000) GS:ffff880007400000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8f461bc000 CR3: 00000001b26ce000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process master (pid: 2436, threadinfo ffff88019e7e8000, task ffff88019e77aea0)
Stack:
ffff88019e7e9ec8 ffffffff810698cd ffff88019e7e9ef8 ffffffff81069b45
<0> ffff880161514180 ffff880161514480 ffff880161514180 0000000000000000
<0> ffff88019e7e9f28 ffffffff8106aace 0000000000000001 0000000000000246
Call Trace:
[<ffffffff810698cd>] put_cred+0x13/0x15
[<ffffffff81069b45>] commit_creds+0x16b/0x175
[<ffffffff8106aace>] set_current_groups+0x47/0x4e
[<ffffffff8106ac89>] sys_setgroups+0xf6/0x105
[<ffffffff81009b02>] system_call_fastpath+0x16/0x1b
Code: 48 8d 71 ff e8 7e 4e 15 00 85 c0 78 0b 8b 75 ec 48 89 df e8 ef 4a 15 00
48 83 c4 18 5b c9 c3 55 8b 07 8b 07 48 89 e5 85 c0 74 04 <0f> 0b eb fe 65 48 8b
04 25 00 cc 00 00 48 3b b8 58 04 00 00 75
RIP [<ffffffff81069881>] __put_cred+0xc/0x45
RSP <ffff88019e7e9eb8>
---[ end trace df391256a100ebdd ]---
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-07-29 11:45:49 +00:00
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cred = get_task_cred(p);
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2008-02-08 12:18:33 +00:00
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seq_printf(m,
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2005-04-16 22:20:36 +00:00
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"State:\t%s\n"
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"Tgid:\t%d\n"
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"Pid:\t%d\n"
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"PPid:\t%d\n"
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"TracerPid:\t%d\n"
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"Uid:\t%d\t%d\t%d\t%d\n"
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"Gid:\t%d\t%d\t%d\t%d\n",
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get_task_state(p),
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2007-10-19 06:40:14 +00:00
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task_tgid_nr_ns(p, ns),
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2008-02-08 12:18:33 +00:00
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pid_nr_ns(pid, ns),
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2007-10-19 06:40:14 +00:00
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ppid, tpid,
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2012-02-09 16:48:21 +00:00
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from_kuid_munged(user_ns, cred->uid),
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from_kuid_munged(user_ns, cred->euid),
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from_kuid_munged(user_ns, cred->suid),
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from_kuid_munged(user_ns, cred->fsuid),
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from_kgid_munged(user_ns, cred->gid),
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from_kgid_munged(user_ns, cred->egid),
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from_kgid_munged(user_ns, cred->sgid),
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from_kgid_munged(user_ns, cred->fsgid));
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2006-10-02 09:18:54 +00:00
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2005-04-16 22:20:36 +00:00
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task_lock(p);
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2005-09-09 20:04:10 +00:00
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if (p->files)
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fdt = files_fdtable(p->files);
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2008-02-08 12:18:33 +00:00
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seq_printf(m,
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2005-04-16 22:20:36 +00:00
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"FDSize:\t%d\n"
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"Groups:\t",
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2005-09-09 20:04:10 +00:00
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fdt ? fdt->max_fds : 0);
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2005-09-17 02:28:13 +00:00
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rcu_read_unlock();
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2005-04-16 22:20:36 +00:00
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2008-11-13 23:39:19 +00:00
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group_info = cred->group_info;
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2005-04-16 22:20:36 +00:00
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task_unlock(p);
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2012-12-18 00:03:17 +00:00
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for (g = 0; g < group_info->ngroups; g++)
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2011-11-14 23:56:38 +00:00
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seq_printf(m, "%d ",
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from_kgid_munged(user_ns, GROUP_AT(group_info, g)));
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2008-11-13 23:39:19 +00:00
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|
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put_cred(cred);
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2005-04-16 22:20:36 +00:00
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2011-01-13 01:00:32 +00:00
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seq_putc(m, '\n');
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2005-04-16 22:20:36 +00:00
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}
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2012-12-18 00:05:02 +00:00
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|
|
void render_sigset_t(struct seq_file *m, const char *header,
|
2008-02-08 12:18:33 +00:00
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|
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sigset_t *set)
|
2005-04-16 22:20:36 +00:00
|
|
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{
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2008-02-08 12:18:33 +00:00
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|
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int i;
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2005-04-16 22:20:36 +00:00
|
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2011-01-13 01:00:32 +00:00
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seq_puts(m, header);
|
2005-04-16 22:20:36 +00:00
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i = _NSIG;
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do {
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int x = 0;
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|
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|
|
i -= 4;
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|
|
if (sigismember(set, i+1)) x |= 1;
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|
|
if (sigismember(set, i+2)) x |= 2;
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if (sigismember(set, i+3)) x |= 4;
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|
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if (sigismember(set, i+4)) x |= 8;
|
2008-02-08 12:18:33 +00:00
|
|
|
seq_printf(m, "%x", x);
|
2005-04-16 22:20:36 +00:00
|
|
|
} while (i >= 4);
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|
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|
2011-01-13 01:00:32 +00:00
|
|
|
seq_putc(m, '\n');
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
static void collect_sigign_sigcatch(struct task_struct *p, sigset_t *ign,
|
|
|
|
sigset_t *catch)
|
|
|
|
{
|
|
|
|
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(ign, i);
|
|
|
|
else if (k->sa.sa_handler != SIG_DFL)
|
|
|
|
sigaddset(catch, i);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2008-02-08 12:18:33 +00:00
|
|
|
static inline void task_sig(struct seq_file *m, struct task_struct *p)
|
2005-04-16 22:20:36 +00:00
|
|
|
{
|
2006-10-02 09:18:52 +00:00
|
|
|
unsigned long flags;
|
2005-04-16 22:20:36 +00:00
|
|
|
sigset_t pending, shpending, blocked, ignored, caught;
|
|
|
|
int num_threads = 0;
|
|
|
|
unsigned long qsize = 0;
|
|
|
|
unsigned long qlim = 0;
|
|
|
|
|
|
|
|
sigemptyset(&pending);
|
|
|
|
sigemptyset(&shpending);
|
|
|
|
sigemptyset(&blocked);
|
|
|
|
sigemptyset(&ignored);
|
|
|
|
sigemptyset(&caught);
|
|
|
|
|
2006-10-02 09:18:52 +00:00
|
|
|
if (lock_task_sighand(p, &flags)) {
|
2005-04-16 22:20:36 +00:00
|
|
|
pending = p->pending.signal;
|
|
|
|
shpending = p->signal->shared_pending.signal;
|
|
|
|
blocked = p->blocked;
|
|
|
|
collect_sigign_sigcatch(p, &ignored, &caught);
|
2010-05-26 21:43:22 +00:00
|
|
|
num_threads = get_nr_threads(p);
|
2010-02-23 01:04:52 +00:00
|
|
|
rcu_read_lock(); /* FIXME: is this correct? */
|
2008-11-13 23:39:19 +00:00
|
|
|
qsize = atomic_read(&__task_cred(p)->user->sigpending);
|
2010-02-23 01:04:52 +00:00
|
|
|
rcu_read_unlock();
|
2010-03-05 21:42:42 +00:00
|
|
|
qlim = task_rlimit(p, RLIMIT_SIGPENDING);
|
2006-10-02 09:18:52 +00:00
|
|
|
unlock_task_sighand(p, &flags);
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
|
|
|
|
2008-02-08 12:18:33 +00:00
|
|
|
seq_printf(m, "Threads:\t%d\n", num_threads);
|
|
|
|
seq_printf(m, "SigQ:\t%lu/%lu\n", qsize, qlim);
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
/* render them all */
|
2008-02-08 12:18:33 +00:00
|
|
|
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);
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
|
|
|
|
2008-02-08 12:18:33 +00:00
|
|
|
static void render_cap_t(struct seq_file *m, const char *header,
|
|
|
|
kernel_cap_t *a)
|
2008-02-05 06:29:42 +00:00
|
|
|
{
|
|
|
|
unsigned __capi;
|
|
|
|
|
2011-01-13 01:00:32 +00:00
|
|
|
seq_puts(m, header);
|
2008-02-05 06:29:42 +00:00
|
|
|
CAP_FOR_EACH_U32(__capi) {
|
2008-02-08 12:18:33 +00:00
|
|
|
seq_printf(m, "%08x",
|
2014-07-23 19:36:26 +00:00
|
|
|
a->cap[CAP_LAST_U32 - __capi]);
|
2008-02-05 06:29:42 +00:00
|
|
|
}
|
2011-01-13 01:00:32 +00:00
|
|
|
seq_putc(m, '\n');
|
2008-02-05 06:29:42 +00:00
|
|
|
}
|
|
|
|
|
2008-02-08 12:18:33 +00:00
|
|
|
static inline void task_cap(struct seq_file *m, struct task_struct *p)
|
2005-04-16 22:20:36 +00:00
|
|
|
{
|
2008-11-13 23:39:19 +00:00
|
|
|
const struct cred *cred;
|
|
|
|
kernel_cap_t cap_inheritable, cap_permitted, cap_effective, cap_bset;
|
2008-11-13 23:39:16 +00:00
|
|
|
|
2008-11-13 23:39:19 +00:00
|
|
|
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;
|
|
|
|
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);
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
|
|
|
|
2012-12-18 00:03:14 +00:00
|
|
|
static inline void task_seccomp(struct seq_file *m, struct task_struct *p)
|
|
|
|
{
|
|
|
|
#ifdef CONFIG_SECCOMP
|
|
|
|
seq_printf(m, "Seccomp:\t%d\n", p->seccomp.mode);
|
|
|
|
#endif
|
|
|
|
}
|
|
|
|
|
2008-02-08 12:18:33 +00:00
|
|
|
static inline void task_context_switch_counts(struct seq_file *m,
|
|
|
|
struct task_struct *p)
|
2007-07-16 06:40:48 +00:00
|
|
|
{
|
2008-02-08 12:18:33 +00:00
|
|
|
seq_printf(m, "voluntary_ctxt_switches:\t%lu\n"
|
|
|
|
"nonvoluntary_ctxt_switches:\t%lu\n",
|
|
|
|
p->nvcsw,
|
|
|
|
p->nivcsw);
|
2007-07-16 06:40:48 +00:00
|
|
|
}
|
|
|
|
|
2009-09-21 09:06:27 +00:00
|
|
|
static void task_cpus_allowed(struct seq_file *m, struct task_struct *task)
|
|
|
|
{
|
2011-01-13 01:00:32 +00:00
|
|
|
seq_puts(m, "Cpus_allowed:\t");
|
2009-09-21 09:06:27 +00:00
|
|
|
seq_cpumask(m, &task->cpus_allowed);
|
2011-01-13 01:00:32 +00:00
|
|
|
seq_putc(m, '\n');
|
|
|
|
seq_puts(m, "Cpus_allowed_list:\t");
|
2009-09-21 09:06:27 +00:00
|
|
|
seq_cpumask_list(m, &task->cpus_allowed);
|
2011-01-13 01:00:32 +00:00
|
|
|
seq_putc(m, '\n');
|
2009-09-21 09:06:27 +00:00
|
|
|
}
|
|
|
|
|
2008-02-08 12:18:33 +00:00
|
|
|
int proc_pid_status(struct seq_file *m, struct pid_namespace *ns,
|
|
|
|
struct pid *pid, struct task_struct *task)
|
2005-04-16 22:20:36 +00:00
|
|
|
{
|
|
|
|
struct mm_struct *mm = get_task_mm(task);
|
|
|
|
|
2008-02-08 12:18:33 +00:00
|
|
|
task_name(m, task);
|
|
|
|
task_state(m, ns, pid, task);
|
2007-07-16 07:46:31 +00:00
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
if (mm) {
|
2008-02-08 12:18:33 +00:00
|
|
|
task_mem(m, mm);
|
2005-04-16 22:20:36 +00:00
|
|
|
mmput(mm);
|
|
|
|
}
|
2008-02-08 12:18:33 +00:00
|
|
|
task_sig(m, task);
|
|
|
|
task_cap(m, task);
|
2012-12-18 00:03:14 +00:00
|
|
|
task_seccomp(m, task);
|
2009-09-21 09:06:27 +00:00
|
|
|
task_cpus_allowed(m, task);
|
2008-02-08 12:18:33 +00:00
|
|
|
cpuset_task_status_allowed(m, task);
|
|
|
|
task_context_switch_counts(m, task);
|
|
|
|
return 0;
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
|
|
|
|
2008-02-08 12:18:31 +00:00
|
|
|
static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
|
|
|
|
struct pid *pid, struct task_struct *task, int whole)
|
2005-04-16 22:20:36 +00:00
|
|
|
{
|
|
|
|
unsigned long vsize, eip, esp, wchan = ~0UL;
|
2012-05-31 23:26:19 +00:00
|
|
|
int priority, nice;
|
2005-04-16 22:20:36 +00:00
|
|
|
int tty_pgrp = -1, tty_nr = 0;
|
|
|
|
sigset_t sigign, sigcatch;
|
|
|
|
char state;
|
2007-07-16 07:46:31 +00:00
|
|
|
pid_t ppid = 0, pgid = -1, sid = -1;
|
2005-04-16 22:20:36 +00:00
|
|
|
int num_threads = 0;
|
2009-05-04 18:51:14 +00:00
|
|
|
int permitted;
|
2005-04-16 22:20:36 +00:00
|
|
|
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;
|
2007-08-23 13:18:02 +00:00
|
|
|
cputime_t cutime, cstime, utime, stime;
|
2007-10-15 15:00:19 +00:00
|
|
|
cputime_t cgtime, gtime;
|
2005-04-16 22:20:36 +00:00
|
|
|
unsigned long rsslim = 0;
|
|
|
|
char tcomm[sizeof(task->comm)];
|
2006-10-02 09:18:53 +00:00
|
|
|
unsigned long flags;
|
2005-04-16 22:20:36 +00:00
|
|
|
|
|
|
|
state = *get_task_state(task);
|
|
|
|
vsize = eip = esp = 0;
|
ptrace: use fsuid, fsgid, effective creds for fs access checks
commit caaee6234d05a58c5b4d05e7bf766131b810a657 upstream.
By checking the effective credentials instead of the real UID / permitted
capabilities, ensure that the calling process actually intended to use its
credentials.
To ensure that all ptrace checks use the correct caller credentials (e.g.
in case out-of-tree code or newly added code omits the PTRACE_MODE_*CREDS
flag), use two new flags and require one of them to be set.
The problem was that when a privileged task had temporarily dropped its
privileges, e.g. by calling setreuid(0, user_uid), with the intent to
perform following syscalls with the credentials of a user, it still passed
ptrace access checks that the user would not be able to pass.
While an attacker should not be able to convince the privileged task to
perform a ptrace() syscall, this is a problem because the ptrace access
check is reused for things in procfs.
In particular, the following somewhat interesting procfs entries only rely
on ptrace access checks:
/proc/$pid/stat - uses the check for determining whether pointers
should be visible, useful for bypassing ASLR
/proc/$pid/maps - also useful for bypassing ASLR
/proc/$pid/cwd - useful for gaining access to restricted
directories that contain files with lax permissions, e.g. in
this scenario:
lrwxrwxrwx root root /proc/13020/cwd -> /root/foobar
drwx------ root root /root
drwxr-xr-x root root /root/foobar
-rw-r--r-- root root /root/foobar/secret
Therefore, on a system where a root-owned mode 6755 binary changes its
effective credentials as described and then dumps a user-specified file,
this could be used by an attacker to reveal the memory layout of root's
processes or reveal the contents of files he is not allowed to access
(through /proc/$pid/cwd).
[akpm@linux-foundation.org: fix warning]
Signed-off-by: Jann Horn <jann@thejh.net>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Casey Schaufler <casey@schaufler-ca.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: "Serge E. Hallyn" <serge.hallyn@ubuntu.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Willy Tarreau <w@1wt.eu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-01-20 23:00:04 +00:00
|
|
|
permitted = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS | PTRACE_MODE_NOAUDIT);
|
2005-04-16 22:20:36 +00:00
|
|
|
mm = get_task_mm(task);
|
|
|
|
if (mm) {
|
|
|
|
vsize = task_vsize(mm);
|
2009-05-04 18:51:14 +00:00
|
|
|
if (permitted) {
|
|
|
|
eip = KSTK_EIP(task);
|
|
|
|
esp = KSTK_ESP(task);
|
|
|
|
}
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
get_task_comm(tcomm, task);
|
|
|
|
|
|
|
|
sigemptyset(&sigign);
|
|
|
|
sigemptyset(&sigcatch);
|
2011-12-15 13:56:09 +00:00
|
|
|
cutime = cstime = utime = stime = 0;
|
|
|
|
cgtime = gtime = 0;
|
2006-09-29 09:00:41 +00:00
|
|
|
|
2006-10-02 09:18:53 +00:00
|
|
|
if (lock_task_sighand(task, &flags)) {
|
|
|
|
struct signal_struct *sig = task->signal;
|
2006-12-08 10:36:07 +00:00
|
|
|
|
|
|
|
if (sig->tty) {
|
2008-04-30 07:53:31 +00:00
|
|
|
struct pid *pgrp = tty_get_pgrp(sig->tty);
|
|
|
|
tty_pgrp = pid_nr_ns(pgrp, ns);
|
|
|
|
put_pid(pgrp);
|
2006-12-08 10:36:07 +00:00
|
|
|
tty_nr = new_encode_dev(tty_devnum(sig->tty));
|
2006-10-02 09:18:53 +00:00
|
|
|
}
|
|
|
|
|
2010-05-26 21:43:22 +00:00
|
|
|
num_threads = get_nr_threads(task);
|
2005-04-16 22:20:36 +00:00
|
|
|
collect_sigign_sigcatch(task, &sigign, &sigcatch);
|
|
|
|
|
2006-10-02 09:18:53 +00:00
|
|
|
cmin_flt = sig->cmin_flt;
|
|
|
|
cmaj_flt = sig->cmaj_flt;
|
|
|
|
cutime = sig->cutime;
|
|
|
|
cstime = sig->cstime;
|
2007-10-15 15:00:19 +00:00
|
|
|
cgtime = sig->cgtime;
|
2010-03-05 21:42:42 +00:00
|
|
|
rsslim = ACCESS_ONCE(sig->rlim[RLIMIT_RSS].rlim_cur);
|
2006-10-02 09:18:53 +00:00
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
/* add up live thread stats at the group level */
|
|
|
|
if (whole) {
|
2006-10-02 09:18:53 +00:00
|
|
|
struct task_struct *t = task;
|
2005-04-16 22:20:36 +00:00
|
|
|
do {
|
|
|
|
min_flt += t->min_flt;
|
|
|
|
maj_flt += t->maj_flt;
|
2012-11-13 13:20:55 +00:00
|
|
|
gtime += task_gtime(t);
|
2005-04-16 22:20:36 +00:00
|
|
|
t = next_thread(t);
|
|
|
|
} while (t != task);
|
|
|
|
|
2006-10-02 09:18:53 +00:00
|
|
|
min_flt += sig->min_flt;
|
|
|
|
maj_flt += sig->maj_flt;
|
2012-11-21 15:26:44 +00:00
|
|
|
thread_group_cputime_adjusted(task, &utime, &stime);
|
2011-12-15 13:56:09 +00:00
|
|
|
gtime += sig->gtime;
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
2006-10-02 09:18:53 +00:00
|
|
|
|
2007-10-19 06:40:14 +00:00
|
|
|
sid = task_session_nr_ns(task, ns);
|
2008-01-14 21:02:37 +00:00
|
|
|
ppid = task_tgid_nr_ns(task->real_parent, ns);
|
2007-10-19 06:40:14 +00:00
|
|
|
pgid = task_pgrp_nr_ns(task, ns);
|
2006-10-02 09:18:53 +00:00
|
|
|
|
|
|
|
unlock_task_sighand(task, &flags);
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
|
|
|
|
2009-05-04 18:51:14 +00:00
|
|
|
if (permitted && (!whole || num_threads < 2))
|
2005-04-16 22:20:36 +00:00
|
|
|
wchan = get_wchan(task);
|
|
|
|
if (!whole) {
|
|
|
|
min_flt = task->min_flt;
|
|
|
|
maj_flt = task->maj_flt;
|
2012-11-21 15:26:44 +00:00
|
|
|
task_cputime_adjusted(task, &utime, &stime);
|
2012-11-13 13:20:55 +00:00
|
|
|
gtime = task_gtime(task);
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
|
|
|
|
|
|
|
/* 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);
|
|
|
|
|
|
|
|
/* Temporary variable needed for gcc-2.96 */
|
|
|
|
/* convert timespec -> nsec*/
|
2007-07-16 06:39:42 +00:00
|
|
|
start_time =
|
|
|
|
(unsigned long long)task->real_start_time.tv_sec * NSEC_PER_SEC
|
|
|
|
+ task->real_start_time.tv_nsec;
|
2005-04-16 22:20:36 +00:00
|
|
|
/* convert nsec -> ticks */
|
|
|
|
start_time = nsec_to_clock_t(start_time);
|
|
|
|
|
2012-03-23 22:02:54 +00:00
|
|
|
seq_printf(m, "%d (%s) %c", pid_nr_ns(pid, ns), tcomm, 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, ' ', cputime_to_clock_t(utime));
|
|
|
|
seq_put_decimal_ull(m, ' ', cputime_to_clock_t(stime));
|
|
|
|
seq_put_decimal_ll(m, ' ', cputime_to_clock_t(cutime));
|
|
|
|
seq_put_decimal_ll(m, ' ', cputime_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);
|
2012-05-31 23:26:19 +00:00
|
|
|
seq_put_decimal_ull(m, ' ', mm ? get_mm_rss(mm) : 0);
|
2012-03-23 22:02:54 +00:00
|
|
|
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);
|
|
|
|
seq_put_decimal_ull(m, ' ', wchan);
|
|
|
|
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, ' ', cputime_to_clock_t(gtime));
|
|
|
|
seq_put_decimal_ll(m, ' ', cputime_to_clock_t(cgtime));
|
2012-05-31 23:26:44 +00:00
|
|
|
|
|
|
|
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_printf(m, " 0 0 0 0 0 0 0");
|
|
|
|
|
|
|
|
if (permitted)
|
|
|
|
seq_put_decimal_ll(m, ' ', task->exit_code);
|
|
|
|
else
|
|
|
|
seq_put_decimal_ll(m, ' ', 0);
|
|
|
|
|
2012-03-23 22:02:54 +00:00
|
|
|
seq_putc(m, '\n');
|
2007-07-16 07:46:31 +00:00
|
|
|
if (mm)
|
2005-04-16 22:20:36 +00:00
|
|
|
mmput(mm);
|
2008-02-08 12:18:31 +00:00
|
|
|
return 0;
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
|
|
|
|
2008-02-08 12:18:31 +00:00
|
|
|
int proc_tid_stat(struct seq_file *m, struct pid_namespace *ns,
|
|
|
|
struct pid *pid, struct task_struct *task)
|
2005-04-16 22:20:36 +00:00
|
|
|
{
|
2008-02-08 12:18:31 +00:00
|
|
|
return do_task_stat(m, ns, pid, task, 0);
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
|
|
|
|
2008-02-08 12:18:31 +00:00
|
|
|
int proc_tgid_stat(struct seq_file *m, struct pid_namespace *ns,
|
|
|
|
struct pid *pid, struct task_struct *task)
|
2005-04-16 22:20:36 +00:00
|
|
|
{
|
2008-02-08 12:18:31 +00:00
|
|
|
return do_task_stat(m, ns, pid, task, 1);
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
|
|
|
|
2008-02-08 12:18:32 +00:00
|
|
|
int proc_pid_statm(struct seq_file *m, struct pid_namespace *ns,
|
|
|
|
struct pid *pid, struct task_struct *task)
|
2005-04-16 22:20:36 +00:00
|
|
|
{
|
2011-01-13 01:00:32 +00:00
|
|
|
unsigned long size = 0, resident = 0, shared = 0, text = 0, data = 0;
|
2005-04-16 22:20:36 +00:00
|
|
|
struct mm_struct *mm = get_task_mm(task);
|
2007-07-16 07:46:31 +00:00
|
|
|
|
2005-04-16 22:20:36 +00:00
|
|
|
if (mm) {
|
|
|
|
size = task_statm(mm, &shared, &text, &data, &resident);
|
|
|
|
mmput(mm);
|
|
|
|
}
|
2012-03-23 22:02:54 +00:00
|
|
|
/*
|
|
|
|
* For quick read, open code by putting numbers directly
|
|
|
|
* expected format is
|
|
|
|
* seq_printf(m, "%lu %lu %lu %lu 0 %lu 0\n",
|
|
|
|
* size, resident, shared, text, data);
|
|
|
|
*/
|
|
|
|
seq_put_decimal_ull(m, 0, 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);
|
2012-03-28 21:42:39 +00:00
|
|
|
seq_put_decimal_ull(m, ' ', data);
|
2012-03-23 22:02:54 +00:00
|
|
|
seq_put_decimal_ull(m, ' ', 0);
|
|
|
|
seq_putc(m, '\n');
|
2005-04-16 22:20:36 +00:00
|
|
|
|
2008-02-08 12:18:32 +00:00
|
|
|
return 0;
|
2005-04-16 22:20:36 +00:00
|
|
|
}
|
2012-05-31 23:26:43 +00:00
|
|
|
|
|
|
|
#ifdef CONFIG_CHECKPOINT_RESTORE
|
|
|
|
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 = seq->private;
|
|
|
|
pid_t pid;
|
|
|
|
|
|
|
|
pid = pid_nr_ns(v, inode->i_sb->s_fs_info);
|
|
|
|
return seq_printf(seq, "%d ", pid);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void *children_seq_start(struct seq_file *seq, loff_t *pos)
|
|
|
|
{
|
|
|
|
return get_children_pid(seq->private, NULL, *pos);
|
|
|
|
}
|
|
|
|
|
|
|
|
static void *children_seq_next(struct seq_file *seq, void *v, loff_t *pos)
|
|
|
|
{
|
|
|
|
struct pid *pid;
|
|
|
|
|
|
|
|
pid = get_children_pid(seq->private, 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)
|
|
|
|
{
|
|
|
|
struct seq_file *m;
|
|
|
|
int ret;
|
|
|
|
|
|
|
|
ret = seq_open(file, &children_seq_ops);
|
|
|
|
if (ret)
|
|
|
|
return ret;
|
|
|
|
|
|
|
|
m = file->private_data;
|
|
|
|
m->private = inode;
|
|
|
|
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
int children_seq_release(struct inode *inode, struct file *file)
|
|
|
|
{
|
|
|
|
seq_release(inode, file);
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
const struct file_operations proc_tid_children_operations = {
|
|
|
|
.open = children_seq_open,
|
|
|
|
.read = seq_read,
|
|
|
|
.llseek = seq_lseek,
|
|
|
|
.release = children_seq_release,
|
|
|
|
};
|
|
|
|
#endif /* CONFIG_CHECKPOINT_RESTORE */
|