7766755a2f
This patch fixes a sles9 system hang in start_this_handle from a customer with some heavy workload where all tasks are waiting on kjournald to commit the transaction, but kjournald waits on t_updates to go down to zero (it never does). This was reported as a lowmem shortage deadlock but when checking the debug data I noticed the VM wasn't under pressure at all (well it was really under vm pressure, because lots of tasks hanged in the VM prune_dcache methods trying to flush dirty inodes, but no task was hanging in GFP_NOFS mode, the holder of the journal handle should have if this was a vm issue in the first place). No task was apparently holding the leftover handle in the committing transaction, so I deduced t_updates was stuck to 1 because a journal_stop was never run by some path (this turned out to be correct). With a debug patch adding proper reverse links and stack trace logging in ext3 deployed in production, I found journal_stop is never run because mark_inode_dirty_sync is called inside release_task called by do_exit. (that was quite fun because I would have never thought about this subtleness, I thought a regular path in ext3 had a bug and it forgot to call journal_stop) do_exit->release_task->mark_inode_dirty_sync->schedule() (will never come back to run journal_stop) The reason is that shrink_dcache_parent is racy by design (feature not a bug) and it can do blocking I/O in some case, but the point is that calling shrink_dcache_parent at the last stage of do_exit isn't safe for self-reaping tasks. I guess the memory pressure of the unbalanced highmem system allowed to trigger this more easily. Now mainline doesn't have this line in iput (like sles9 has): if (inode->i_state & I_DIRTY_DELAYED) mark_inode_dirty_sync(inode); so it will probably not crash with ext3, but for example ext2 implements an I/O-blocking ext2_put_inode that will lead to similar screwups with ext2_free_blocks never coming back and it's definitely wrong to call blocking-IO paths inside do_exit. So this should fix a subtle bug in mainline too (not verified in practice though). The equivalent fix for ext3 is also not verified yet to fix the problem in sles9 but I don't have doubt it will (it usually takes days to crash, so it'll take weeks to be sure). An alternate fix would be to offload that work to a kernel thread, but I don't think a reschedule for this is worth it, the vm should be able to collect those entries for the synchronous release_task. Signed-off-by: Andrea Arcangeli <andrea@suse.de> Cc: Jan Kara <jack@ucw.cz> Cc: Ingo Molnar <mingo@elte.hu> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2872 lines
67 KiB
C
2872 lines
67 KiB
C
/*
|
|
* linux/fs/proc/base.c
|
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*
|
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* Copyright (C) 1991, 1992 Linus Torvalds
|
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*
|
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* proc base directory handling functions
|
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*
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* 1999, Al Viro. Rewritten. Now it covers the whole per-process part.
|
|
* Instead of using magical inumbers to determine the kind of object
|
|
* we allocate and fill in-core inodes upon lookup. They don't even
|
|
* go into icache. We cache the reference to task_struct upon lookup too.
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* Eventually it should become a filesystem in its own. We don't use the
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* rest of procfs anymore.
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*
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*
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* Changelog:
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* 17-Jan-2005
|
|
* Allan Bezerra
|
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* Bruna Moreira <bruna.moreira@indt.org.br>
|
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* Edjard Mota <edjard.mota@indt.org.br>
|
|
* Ilias Biris <ilias.biris@indt.org.br>
|
|
* Mauricio Lin <mauricio.lin@indt.org.br>
|
|
*
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|
* Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT
|
|
*
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|
* A new process specific entry (smaps) included in /proc. It shows the
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* size of rss for each memory area. The maps entry lacks information
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* about physical memory size (rss) for each mapped file, i.e.,
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* rss information for executables and library files.
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* This additional information is useful for any tools that need to know
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* about physical memory consumption for a process specific library.
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*
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* Changelog:
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|
* 21-Feb-2005
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* Embedded Linux Lab - 10LE Instituto Nokia de Tecnologia - INdT
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* Pud inclusion in the page table walking.
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*
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* ChangeLog:
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* 10-Mar-2005
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* 10LE Instituto Nokia de Tecnologia - INdT:
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* A better way to walks through the page table as suggested by Hugh Dickins.
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*
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* Simo Piiroinen <simo.piiroinen@nokia.com>:
|
|
* Smaps information related to shared, private, clean and dirty pages.
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|
*
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* Paul Mundt <paul.mundt@nokia.com>:
|
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* Overall revision about smaps.
|
|
*/
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|
|
#include <asm/uaccess.h>
|
|
|
|
#include <linux/errno.h>
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|
#include <linux/time.h>
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#include <linux/proc_fs.h>
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#include <linux/stat.h>
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|
#include <linux/init.h>
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#include <linux/capability.h>
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|
#include <linux/file.h>
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|
#include <linux/string.h>
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|
#include <linux/seq_file.h>
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|
#include <linux/namei.h>
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|
#include <linux/mnt_namespace.h>
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|
#include <linux/mm.h>
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|
#include <linux/rcupdate.h>
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|
#include <linux/kallsyms.h>
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|
#include <linux/resource.h>
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|
#include <linux/module.h>
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|
#include <linux/mount.h>
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|
#include <linux/security.h>
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|
#include <linux/ptrace.h>
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|
#include <linux/cgroup.h>
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|
#include <linux/cpuset.h>
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|
#include <linux/audit.h>
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|
#include <linux/poll.h>
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|
#include <linux/nsproxy.h>
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|
#include <linux/oom.h>
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|
#include <linux/elf.h>
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|
#include <linux/pid_namespace.h>
|
|
#include "internal.h"
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|
|
|
/* NOTE:
|
|
* Implementing inode permission operations in /proc is almost
|
|
* certainly an error. Permission checks need to happen during
|
|
* each system call not at open time. The reason is that most of
|
|
* what we wish to check for permissions in /proc varies at runtime.
|
|
*
|
|
* The classic example of a problem is opening file descriptors
|
|
* in /proc for a task before it execs a suid executable.
|
|
*/
|
|
|
|
struct pid_entry {
|
|
char *name;
|
|
int len;
|
|
mode_t mode;
|
|
const struct inode_operations *iop;
|
|
const struct file_operations *fop;
|
|
union proc_op op;
|
|
};
|
|
|
|
#define NOD(NAME, MODE, IOP, FOP, OP) { \
|
|
.name = (NAME), \
|
|
.len = sizeof(NAME) - 1, \
|
|
.mode = MODE, \
|
|
.iop = IOP, \
|
|
.fop = FOP, \
|
|
.op = OP, \
|
|
}
|
|
|
|
#define DIR(NAME, MODE, OTYPE) \
|
|
NOD(NAME, (S_IFDIR|(MODE)), \
|
|
&proc_##OTYPE##_inode_operations, &proc_##OTYPE##_operations, \
|
|
{} )
|
|
#define LNK(NAME, OTYPE) \
|
|
NOD(NAME, (S_IFLNK|S_IRWXUGO), \
|
|
&proc_pid_link_inode_operations, NULL, \
|
|
{ .proc_get_link = &proc_##OTYPE##_link } )
|
|
#define REG(NAME, MODE, OTYPE) \
|
|
NOD(NAME, (S_IFREG|(MODE)), NULL, \
|
|
&proc_##OTYPE##_operations, {})
|
|
#define INF(NAME, MODE, OTYPE) \
|
|
NOD(NAME, (S_IFREG|(MODE)), \
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|
NULL, &proc_info_file_operations, \
|
|
{ .proc_read = &proc_##OTYPE } )
|
|
|
|
int maps_protect;
|
|
EXPORT_SYMBOL(maps_protect);
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|
|
|
static struct fs_struct *get_fs_struct(struct task_struct *task)
|
|
{
|
|
struct fs_struct *fs;
|
|
task_lock(task);
|
|
fs = task->fs;
|
|
if(fs)
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|
atomic_inc(&fs->count);
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|
task_unlock(task);
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|
return fs;
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|
}
|
|
|
|
static int get_nr_threads(struct task_struct *tsk)
|
|
{
|
|
/* Must be called with the rcu_read_lock held */
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|
unsigned long flags;
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|
int count = 0;
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|
|
|
if (lock_task_sighand(tsk, &flags)) {
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|
count = atomic_read(&tsk->signal->count);
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|
unlock_task_sighand(tsk, &flags);
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|
}
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|
return count;
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|
}
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|
|
|
static int proc_cwd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt)
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|
{
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|
struct task_struct *task = get_proc_task(inode);
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struct fs_struct *fs = NULL;
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|
int result = -ENOENT;
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|
|
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if (task) {
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|
fs = get_fs_struct(task);
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|
put_task_struct(task);
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|
}
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if (fs) {
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|
read_lock(&fs->lock);
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|
*mnt = mntget(fs->pwdmnt);
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|
*dentry = dget(fs->pwd);
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|
read_unlock(&fs->lock);
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|
result = 0;
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|
put_fs_struct(fs);
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|
}
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|
return result;
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|
}
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|
|
|
static int proc_root_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt)
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|
{
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|
struct task_struct *task = get_proc_task(inode);
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struct fs_struct *fs = NULL;
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int result = -ENOENT;
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|
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if (task) {
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fs = get_fs_struct(task);
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|
put_task_struct(task);
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|
}
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if (fs) {
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|
read_lock(&fs->lock);
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|
*mnt = mntget(fs->rootmnt);
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|
*dentry = dget(fs->root);
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|
read_unlock(&fs->lock);
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result = 0;
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|
put_fs_struct(fs);
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}
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return result;
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|
}
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|
|
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#define MAY_PTRACE(task) \
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(task == current || \
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(task->parent == current && \
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(task->ptrace & PT_PTRACED) && \
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(task_is_stopped_or_traced(task)) && \
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|
security_ptrace(current,task) == 0))
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|
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struct mm_struct *mm_for_maps(struct task_struct *task)
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|
{
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struct mm_struct *mm = get_task_mm(task);
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if (!mm)
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return NULL;
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down_read(&mm->mmap_sem);
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task_lock(task);
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if (task->mm != mm)
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goto out;
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if (task->mm != current->mm && __ptrace_may_attach(task) < 0)
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goto out;
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task_unlock(task);
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return mm;
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out:
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|
task_unlock(task);
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up_read(&mm->mmap_sem);
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|
mmput(mm);
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return NULL;
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}
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|
|
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static int proc_pid_cmdline(struct task_struct *task, char * buffer)
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|
{
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|
int res = 0;
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|
unsigned int len;
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struct mm_struct *mm = get_task_mm(task);
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if (!mm)
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goto out;
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if (!mm->arg_end)
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goto out_mm; /* Shh! No looking before we're done */
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len = mm->arg_end - mm->arg_start;
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if (len > PAGE_SIZE)
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len = PAGE_SIZE;
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res = access_process_vm(task, mm->arg_start, buffer, len, 0);
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|
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// If the nul at the end of args has been overwritten, then
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// assume application is using setproctitle(3).
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if (res > 0 && buffer[res-1] != '\0' && len < PAGE_SIZE) {
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len = strnlen(buffer, res);
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if (len < res) {
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res = len;
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} else {
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len = mm->env_end - mm->env_start;
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if (len > PAGE_SIZE - res)
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len = PAGE_SIZE - res;
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res += access_process_vm(task, mm->env_start, buffer+res, len, 0);
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res = strnlen(buffer, res);
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}
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}
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|
out_mm:
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|
mmput(mm);
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|
out:
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|
return res;
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|
}
|
|
|
|
static int proc_pid_auxv(struct task_struct *task, char *buffer)
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|
{
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|
int res = 0;
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|
struct mm_struct *mm = get_task_mm(task);
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|
if (mm) {
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|
unsigned int nwords = 0;
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do
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nwords += 2;
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while (mm->saved_auxv[nwords - 2] != 0); /* AT_NULL */
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|
res = nwords * sizeof(mm->saved_auxv[0]);
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|
if (res > PAGE_SIZE)
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|
res = PAGE_SIZE;
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|
memcpy(buffer, mm->saved_auxv, res);
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|
mmput(mm);
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|
}
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return res;
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}
|
|
|
|
|
|
#ifdef CONFIG_KALLSYMS
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/*
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|
* Provides a wchan file via kallsyms in a proper one-value-per-file format.
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* Returns the resolved symbol. If that fails, simply return the address.
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*/
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static int proc_pid_wchan(struct task_struct *task, char *buffer)
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|
{
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|
unsigned long wchan;
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char symname[KSYM_NAME_LEN];
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|
|
|
wchan = get_wchan(task);
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|
|
|
if (lookup_symbol_name(wchan, symname) < 0)
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|
return sprintf(buffer, "%lu", wchan);
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|
else
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|
return sprintf(buffer, "%s", symname);
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|
}
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#endif /* CONFIG_KALLSYMS */
|
|
|
|
#ifdef CONFIG_SCHEDSTATS
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/*
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* Provides /proc/PID/schedstat
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*/
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static int proc_pid_schedstat(struct task_struct *task, char *buffer)
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|
{
|
|
return sprintf(buffer, "%llu %llu %lu\n",
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task->sched_info.cpu_time,
|
|
task->sched_info.run_delay,
|
|
task->sched_info.pcount);
|
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}
|
|
#endif
|
|
|
|
#ifdef CONFIG_LATENCYTOP
|
|
static int lstats_show_proc(struct seq_file *m, void *v)
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|
{
|
|
int i;
|
|
struct task_struct *task = m->private;
|
|
seq_puts(m, "Latency Top version : v0.1\n");
|
|
|
|
for (i = 0; i < 32; i++) {
|
|
if (task->latency_record[i].backtrace[0]) {
|
|
int q;
|
|
seq_printf(m, "%i %li %li ",
|
|
task->latency_record[i].count,
|
|
task->latency_record[i].time,
|
|
task->latency_record[i].max);
|
|
for (q = 0; q < LT_BACKTRACEDEPTH; q++) {
|
|
char sym[KSYM_NAME_LEN];
|
|
char *c;
|
|
if (!task->latency_record[i].backtrace[q])
|
|
break;
|
|
if (task->latency_record[i].backtrace[q] == ULONG_MAX)
|
|
break;
|
|
sprint_symbol(sym, task->latency_record[i].backtrace[q]);
|
|
c = strchr(sym, '+');
|
|
if (c)
|
|
*c = 0;
|
|
seq_printf(m, "%s ", sym);
|
|
}
|
|
seq_printf(m, "\n");
|
|
}
|
|
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int lstats_open(struct inode *inode, struct file *file)
|
|
{
|
|
int ret;
|
|
struct seq_file *m;
|
|
struct task_struct *task = get_proc_task(inode);
|
|
|
|
ret = single_open(file, lstats_show_proc, NULL);
|
|
if (!ret) {
|
|
m = file->private_data;
|
|
m->private = task;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static ssize_t lstats_write(struct file *file, const char __user *buf,
|
|
size_t count, loff_t *offs)
|
|
{
|
|
struct seq_file *m;
|
|
struct task_struct *task;
|
|
|
|
m = file->private_data;
|
|
task = m->private;
|
|
clear_all_latency_tracing(task);
|
|
|
|
return count;
|
|
}
|
|
|
|
static const struct file_operations proc_lstats_operations = {
|
|
.open = lstats_open,
|
|
.read = seq_read,
|
|
.write = lstats_write,
|
|
.llseek = seq_lseek,
|
|
.release = single_release,
|
|
};
|
|
|
|
#endif
|
|
|
|
/* The badness from the OOM killer */
|
|
unsigned long badness(struct task_struct *p, unsigned long uptime);
|
|
static int proc_oom_score(struct task_struct *task, char *buffer)
|
|
{
|
|
unsigned long points;
|
|
struct timespec uptime;
|
|
|
|
do_posix_clock_monotonic_gettime(&uptime);
|
|
read_lock(&tasklist_lock);
|
|
points = badness(task, uptime.tv_sec);
|
|
read_unlock(&tasklist_lock);
|
|
return sprintf(buffer, "%lu\n", points);
|
|
}
|
|
|
|
struct limit_names {
|
|
char *name;
|
|
char *unit;
|
|
};
|
|
|
|
static const struct limit_names lnames[RLIM_NLIMITS] = {
|
|
[RLIMIT_CPU] = {"Max cpu time", "ms"},
|
|
[RLIMIT_FSIZE] = {"Max file size", "bytes"},
|
|
[RLIMIT_DATA] = {"Max data size", "bytes"},
|
|
[RLIMIT_STACK] = {"Max stack size", "bytes"},
|
|
[RLIMIT_CORE] = {"Max core file size", "bytes"},
|
|
[RLIMIT_RSS] = {"Max resident set", "bytes"},
|
|
[RLIMIT_NPROC] = {"Max processes", "processes"},
|
|
[RLIMIT_NOFILE] = {"Max open files", "files"},
|
|
[RLIMIT_MEMLOCK] = {"Max locked memory", "bytes"},
|
|
[RLIMIT_AS] = {"Max address space", "bytes"},
|
|
[RLIMIT_LOCKS] = {"Max file locks", "locks"},
|
|
[RLIMIT_SIGPENDING] = {"Max pending signals", "signals"},
|
|
[RLIMIT_MSGQUEUE] = {"Max msgqueue size", "bytes"},
|
|
[RLIMIT_NICE] = {"Max nice priority", NULL},
|
|
[RLIMIT_RTPRIO] = {"Max realtime priority", NULL},
|
|
};
|
|
|
|
/* Display limits for a process */
|
|
static int proc_pid_limits(struct task_struct *task, char *buffer)
|
|
{
|
|
unsigned int i;
|
|
int count = 0;
|
|
unsigned long flags;
|
|
char *bufptr = buffer;
|
|
|
|
struct rlimit rlim[RLIM_NLIMITS];
|
|
|
|
rcu_read_lock();
|
|
if (!lock_task_sighand(task,&flags)) {
|
|
rcu_read_unlock();
|
|
return 0;
|
|
}
|
|
memcpy(rlim, task->signal->rlim, sizeof(struct rlimit) * RLIM_NLIMITS);
|
|
unlock_task_sighand(task, &flags);
|
|
rcu_read_unlock();
|
|
|
|
/*
|
|
* print the file header
|
|
*/
|
|
count += sprintf(&bufptr[count], "%-25s %-20s %-20s %-10s\n",
|
|
"Limit", "Soft Limit", "Hard Limit", "Units");
|
|
|
|
for (i = 0; i < RLIM_NLIMITS; i++) {
|
|
if (rlim[i].rlim_cur == RLIM_INFINITY)
|
|
count += sprintf(&bufptr[count], "%-25s %-20s ",
|
|
lnames[i].name, "unlimited");
|
|
else
|
|
count += sprintf(&bufptr[count], "%-25s %-20lu ",
|
|
lnames[i].name, rlim[i].rlim_cur);
|
|
|
|
if (rlim[i].rlim_max == RLIM_INFINITY)
|
|
count += sprintf(&bufptr[count], "%-20s ", "unlimited");
|
|
else
|
|
count += sprintf(&bufptr[count], "%-20lu ",
|
|
rlim[i].rlim_max);
|
|
|
|
if (lnames[i].unit)
|
|
count += sprintf(&bufptr[count], "%-10s\n",
|
|
lnames[i].unit);
|
|
else
|
|
count += sprintf(&bufptr[count], "\n");
|
|
}
|
|
|
|
return count;
|
|
}
|
|
|
|
/************************************************************************/
|
|
/* Here the fs part begins */
|
|
/************************************************************************/
|
|
|
|
/* permission checks */
|
|
static int proc_fd_access_allowed(struct inode *inode)
|
|
{
|
|
struct task_struct *task;
|
|
int allowed = 0;
|
|
/* Allow access to a task's file descriptors if it is us or we
|
|
* may use ptrace attach to the process and find out that
|
|
* information.
|
|
*/
|
|
task = get_proc_task(inode);
|
|
if (task) {
|
|
allowed = ptrace_may_attach(task);
|
|
put_task_struct(task);
|
|
}
|
|
return allowed;
|
|
}
|
|
|
|
static int proc_setattr(struct dentry *dentry, struct iattr *attr)
|
|
{
|
|
int error;
|
|
struct inode *inode = dentry->d_inode;
|
|
|
|
if (attr->ia_valid & ATTR_MODE)
|
|
return -EPERM;
|
|
|
|
error = inode_change_ok(inode, attr);
|
|
if (!error)
|
|
error = inode_setattr(inode, attr);
|
|
return error;
|
|
}
|
|
|
|
static const struct inode_operations proc_def_inode_operations = {
|
|
.setattr = proc_setattr,
|
|
};
|
|
|
|
extern struct seq_operations mounts_op;
|
|
struct proc_mounts {
|
|
struct seq_file m;
|
|
int event;
|
|
};
|
|
|
|
static int mounts_open(struct inode *inode, struct file *file)
|
|
{
|
|
struct task_struct *task = get_proc_task(inode);
|
|
struct nsproxy *nsp;
|
|
struct mnt_namespace *ns = NULL;
|
|
struct proc_mounts *p;
|
|
int ret = -EINVAL;
|
|
|
|
if (task) {
|
|
rcu_read_lock();
|
|
nsp = task_nsproxy(task);
|
|
if (nsp) {
|
|
ns = nsp->mnt_ns;
|
|
if (ns)
|
|
get_mnt_ns(ns);
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
put_task_struct(task);
|
|
}
|
|
|
|
if (ns) {
|
|
ret = -ENOMEM;
|
|
p = kmalloc(sizeof(struct proc_mounts), GFP_KERNEL);
|
|
if (p) {
|
|
file->private_data = &p->m;
|
|
ret = seq_open(file, &mounts_op);
|
|
if (!ret) {
|
|
p->m.private = ns;
|
|
p->event = ns->event;
|
|
return 0;
|
|
}
|
|
kfree(p);
|
|
}
|
|
put_mnt_ns(ns);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static int mounts_release(struct inode *inode, struct file *file)
|
|
{
|
|
struct seq_file *m = file->private_data;
|
|
struct mnt_namespace *ns = m->private;
|
|
put_mnt_ns(ns);
|
|
return seq_release(inode, file);
|
|
}
|
|
|
|
static unsigned mounts_poll(struct file *file, poll_table *wait)
|
|
{
|
|
struct proc_mounts *p = file->private_data;
|
|
struct mnt_namespace *ns = p->m.private;
|
|
unsigned res = 0;
|
|
|
|
poll_wait(file, &ns->poll, wait);
|
|
|
|
spin_lock(&vfsmount_lock);
|
|
if (p->event != ns->event) {
|
|
p->event = ns->event;
|
|
res = POLLERR;
|
|
}
|
|
spin_unlock(&vfsmount_lock);
|
|
|
|
return res;
|
|
}
|
|
|
|
static const struct file_operations proc_mounts_operations = {
|
|
.open = mounts_open,
|
|
.read = seq_read,
|
|
.llseek = seq_lseek,
|
|
.release = mounts_release,
|
|
.poll = mounts_poll,
|
|
};
|
|
|
|
extern struct seq_operations mountstats_op;
|
|
static int mountstats_open(struct inode *inode, struct file *file)
|
|
{
|
|
int ret = seq_open(file, &mountstats_op);
|
|
|
|
if (!ret) {
|
|
struct seq_file *m = file->private_data;
|
|
struct nsproxy *nsp;
|
|
struct mnt_namespace *mnt_ns = NULL;
|
|
struct task_struct *task = get_proc_task(inode);
|
|
|
|
if (task) {
|
|
rcu_read_lock();
|
|
nsp = task_nsproxy(task);
|
|
if (nsp) {
|
|
mnt_ns = nsp->mnt_ns;
|
|
if (mnt_ns)
|
|
get_mnt_ns(mnt_ns);
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
put_task_struct(task);
|
|
}
|
|
|
|
if (mnt_ns)
|
|
m->private = mnt_ns;
|
|
else {
|
|
seq_release(inode, file);
|
|
ret = -EINVAL;
|
|
}
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static const struct file_operations proc_mountstats_operations = {
|
|
.open = mountstats_open,
|
|
.read = seq_read,
|
|
.llseek = seq_lseek,
|
|
.release = mounts_release,
|
|
};
|
|
|
|
#define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */
|
|
|
|
static ssize_t proc_info_read(struct file * file, char __user * buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
struct inode * inode = file->f_path.dentry->d_inode;
|
|
unsigned long page;
|
|
ssize_t length;
|
|
struct task_struct *task = get_proc_task(inode);
|
|
|
|
length = -ESRCH;
|
|
if (!task)
|
|
goto out_no_task;
|
|
|
|
if (count > PROC_BLOCK_SIZE)
|
|
count = PROC_BLOCK_SIZE;
|
|
|
|
length = -ENOMEM;
|
|
if (!(page = __get_free_page(GFP_TEMPORARY)))
|
|
goto out;
|
|
|
|
length = PROC_I(inode)->op.proc_read(task, (char*)page);
|
|
|
|
if (length >= 0)
|
|
length = simple_read_from_buffer(buf, count, ppos, (char *)page, length);
|
|
free_page(page);
|
|
out:
|
|
put_task_struct(task);
|
|
out_no_task:
|
|
return length;
|
|
}
|
|
|
|
static const struct file_operations proc_info_file_operations = {
|
|
.read = proc_info_read,
|
|
};
|
|
|
|
static int mem_open(struct inode* inode, struct file* file)
|
|
{
|
|
file->private_data = (void*)((long)current->self_exec_id);
|
|
return 0;
|
|
}
|
|
|
|
static ssize_t mem_read(struct file * file, char __user * buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
|
|
char *page;
|
|
unsigned long src = *ppos;
|
|
int ret = -ESRCH;
|
|
struct mm_struct *mm;
|
|
|
|
if (!task)
|
|
goto out_no_task;
|
|
|
|
if (!MAY_PTRACE(task) || !ptrace_may_attach(task))
|
|
goto out;
|
|
|
|
ret = -ENOMEM;
|
|
page = (char *)__get_free_page(GFP_TEMPORARY);
|
|
if (!page)
|
|
goto out;
|
|
|
|
ret = 0;
|
|
|
|
mm = get_task_mm(task);
|
|
if (!mm)
|
|
goto out_free;
|
|
|
|
ret = -EIO;
|
|
|
|
if (file->private_data != (void*)((long)current->self_exec_id))
|
|
goto out_put;
|
|
|
|
ret = 0;
|
|
|
|
while (count > 0) {
|
|
int this_len, retval;
|
|
|
|
this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
|
|
retval = access_process_vm(task, src, page, this_len, 0);
|
|
if (!retval || !MAY_PTRACE(task) || !ptrace_may_attach(task)) {
|
|
if (!ret)
|
|
ret = -EIO;
|
|
break;
|
|
}
|
|
|
|
if (copy_to_user(buf, page, retval)) {
|
|
ret = -EFAULT;
|
|
break;
|
|
}
|
|
|
|
ret += retval;
|
|
src += retval;
|
|
buf += retval;
|
|
count -= retval;
|
|
}
|
|
*ppos = src;
|
|
|
|
out_put:
|
|
mmput(mm);
|
|
out_free:
|
|
free_page((unsigned long) page);
|
|
out:
|
|
put_task_struct(task);
|
|
out_no_task:
|
|
return ret;
|
|
}
|
|
|
|
#define mem_write NULL
|
|
|
|
#ifndef mem_write
|
|
/* This is a security hazard */
|
|
static ssize_t mem_write(struct file * file, const char __user *buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
int copied;
|
|
char *page;
|
|
struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
|
|
unsigned long dst = *ppos;
|
|
|
|
copied = -ESRCH;
|
|
if (!task)
|
|
goto out_no_task;
|
|
|
|
if (!MAY_PTRACE(task) || !ptrace_may_attach(task))
|
|
goto out;
|
|
|
|
copied = -ENOMEM;
|
|
page = (char *)__get_free_page(GFP_TEMPORARY);
|
|
if (!page)
|
|
goto out;
|
|
|
|
copied = 0;
|
|
while (count > 0) {
|
|
int this_len, retval;
|
|
|
|
this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
|
|
if (copy_from_user(page, buf, this_len)) {
|
|
copied = -EFAULT;
|
|
break;
|
|
}
|
|
retval = access_process_vm(task, dst, page, this_len, 1);
|
|
if (!retval) {
|
|
if (!copied)
|
|
copied = -EIO;
|
|
break;
|
|
}
|
|
copied += retval;
|
|
buf += retval;
|
|
dst += retval;
|
|
count -= retval;
|
|
}
|
|
*ppos = dst;
|
|
free_page((unsigned long) page);
|
|
out:
|
|
put_task_struct(task);
|
|
out_no_task:
|
|
return copied;
|
|
}
|
|
#endif
|
|
|
|
loff_t mem_lseek(struct file *file, loff_t offset, int orig)
|
|
{
|
|
switch (orig) {
|
|
case 0:
|
|
file->f_pos = offset;
|
|
break;
|
|
case 1:
|
|
file->f_pos += offset;
|
|
break;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
force_successful_syscall_return();
|
|
return file->f_pos;
|
|
}
|
|
|
|
static const struct file_operations proc_mem_operations = {
|
|
.llseek = mem_lseek,
|
|
.read = mem_read,
|
|
.write = mem_write,
|
|
.open = mem_open,
|
|
};
|
|
|
|
static ssize_t environ_read(struct file *file, char __user *buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
|
|
char *page;
|
|
unsigned long src = *ppos;
|
|
int ret = -ESRCH;
|
|
struct mm_struct *mm;
|
|
|
|
if (!task)
|
|
goto out_no_task;
|
|
|
|
if (!ptrace_may_attach(task))
|
|
goto out;
|
|
|
|
ret = -ENOMEM;
|
|
page = (char *)__get_free_page(GFP_TEMPORARY);
|
|
if (!page)
|
|
goto out;
|
|
|
|
ret = 0;
|
|
|
|
mm = get_task_mm(task);
|
|
if (!mm)
|
|
goto out_free;
|
|
|
|
while (count > 0) {
|
|
int this_len, retval, max_len;
|
|
|
|
this_len = mm->env_end - (mm->env_start + src);
|
|
|
|
if (this_len <= 0)
|
|
break;
|
|
|
|
max_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
|
|
this_len = (this_len > max_len) ? max_len : this_len;
|
|
|
|
retval = access_process_vm(task, (mm->env_start + src),
|
|
page, this_len, 0);
|
|
|
|
if (retval <= 0) {
|
|
ret = retval;
|
|
break;
|
|
}
|
|
|
|
if (copy_to_user(buf, page, retval)) {
|
|
ret = -EFAULT;
|
|
break;
|
|
}
|
|
|
|
ret += retval;
|
|
src += retval;
|
|
buf += retval;
|
|
count -= retval;
|
|
}
|
|
*ppos = src;
|
|
|
|
mmput(mm);
|
|
out_free:
|
|
free_page((unsigned long) page);
|
|
out:
|
|
put_task_struct(task);
|
|
out_no_task:
|
|
return ret;
|
|
}
|
|
|
|
static const struct file_operations proc_environ_operations = {
|
|
.read = environ_read,
|
|
};
|
|
|
|
static ssize_t oom_adjust_read(struct file *file, char __user *buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
|
|
char buffer[PROC_NUMBUF];
|
|
size_t len;
|
|
int oom_adjust;
|
|
|
|
if (!task)
|
|
return -ESRCH;
|
|
oom_adjust = task->oomkilladj;
|
|
put_task_struct(task);
|
|
|
|
len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust);
|
|
|
|
return simple_read_from_buffer(buf, count, ppos, buffer, len);
|
|
}
|
|
|
|
static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
struct task_struct *task;
|
|
char buffer[PROC_NUMBUF], *end;
|
|
int oom_adjust;
|
|
|
|
memset(buffer, 0, sizeof(buffer));
|
|
if (count > sizeof(buffer) - 1)
|
|
count = sizeof(buffer) - 1;
|
|
if (copy_from_user(buffer, buf, count))
|
|
return -EFAULT;
|
|
oom_adjust = simple_strtol(buffer, &end, 0);
|
|
if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) &&
|
|
oom_adjust != OOM_DISABLE)
|
|
return -EINVAL;
|
|
if (*end == '\n')
|
|
end++;
|
|
task = get_proc_task(file->f_path.dentry->d_inode);
|
|
if (!task)
|
|
return -ESRCH;
|
|
if (oom_adjust < task->oomkilladj && !capable(CAP_SYS_RESOURCE)) {
|
|
put_task_struct(task);
|
|
return -EACCES;
|
|
}
|
|
task->oomkilladj = oom_adjust;
|
|
put_task_struct(task);
|
|
if (end - buffer == 0)
|
|
return -EIO;
|
|
return end - buffer;
|
|
}
|
|
|
|
static const struct file_operations proc_oom_adjust_operations = {
|
|
.read = oom_adjust_read,
|
|
.write = oom_adjust_write,
|
|
};
|
|
|
|
#ifdef CONFIG_AUDITSYSCALL
|
|
#define TMPBUFLEN 21
|
|
static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
struct inode * inode = file->f_path.dentry->d_inode;
|
|
struct task_struct *task = get_proc_task(inode);
|
|
ssize_t length;
|
|
char tmpbuf[TMPBUFLEN];
|
|
|
|
if (!task)
|
|
return -ESRCH;
|
|
length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
|
|
audit_get_loginuid(task));
|
|
put_task_struct(task);
|
|
return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
|
|
}
|
|
|
|
static ssize_t proc_loginuid_write(struct file * file, const char __user * buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
struct inode * inode = file->f_path.dentry->d_inode;
|
|
char *page, *tmp;
|
|
ssize_t length;
|
|
uid_t loginuid;
|
|
|
|
if (!capable(CAP_AUDIT_CONTROL))
|
|
return -EPERM;
|
|
|
|
if (current != pid_task(proc_pid(inode), PIDTYPE_PID))
|
|
return -EPERM;
|
|
|
|
if (count >= PAGE_SIZE)
|
|
count = PAGE_SIZE - 1;
|
|
|
|
if (*ppos != 0) {
|
|
/* No partial writes. */
|
|
return -EINVAL;
|
|
}
|
|
page = (char*)__get_free_page(GFP_TEMPORARY);
|
|
if (!page)
|
|
return -ENOMEM;
|
|
length = -EFAULT;
|
|
if (copy_from_user(page, buf, count))
|
|
goto out_free_page;
|
|
|
|
page[count] = '\0';
|
|
loginuid = simple_strtoul(page, &tmp, 10);
|
|
if (tmp == page) {
|
|
length = -EINVAL;
|
|
goto out_free_page;
|
|
|
|
}
|
|
length = audit_set_loginuid(current, loginuid);
|
|
if (likely(length == 0))
|
|
length = count;
|
|
|
|
out_free_page:
|
|
free_page((unsigned long) page);
|
|
return length;
|
|
}
|
|
|
|
static const struct file_operations proc_loginuid_operations = {
|
|
.read = proc_loginuid_read,
|
|
.write = proc_loginuid_write,
|
|
};
|
|
#endif
|
|
|
|
#ifdef CONFIG_FAULT_INJECTION
|
|
static ssize_t proc_fault_inject_read(struct file * file, char __user * buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
|
|
char buffer[PROC_NUMBUF];
|
|
size_t len;
|
|
int make_it_fail;
|
|
|
|
if (!task)
|
|
return -ESRCH;
|
|
make_it_fail = task->make_it_fail;
|
|
put_task_struct(task);
|
|
|
|
len = snprintf(buffer, sizeof(buffer), "%i\n", make_it_fail);
|
|
|
|
return simple_read_from_buffer(buf, count, ppos, buffer, len);
|
|
}
|
|
|
|
static ssize_t proc_fault_inject_write(struct file * file,
|
|
const char __user * buf, size_t count, loff_t *ppos)
|
|
{
|
|
struct task_struct *task;
|
|
char buffer[PROC_NUMBUF], *end;
|
|
int make_it_fail;
|
|
|
|
if (!capable(CAP_SYS_RESOURCE))
|
|
return -EPERM;
|
|
memset(buffer, 0, sizeof(buffer));
|
|
if (count > sizeof(buffer) - 1)
|
|
count = sizeof(buffer) - 1;
|
|
if (copy_from_user(buffer, buf, count))
|
|
return -EFAULT;
|
|
make_it_fail = simple_strtol(buffer, &end, 0);
|
|
if (*end == '\n')
|
|
end++;
|
|
task = get_proc_task(file->f_dentry->d_inode);
|
|
if (!task)
|
|
return -ESRCH;
|
|
task->make_it_fail = make_it_fail;
|
|
put_task_struct(task);
|
|
if (end - buffer == 0)
|
|
return -EIO;
|
|
return end - buffer;
|
|
}
|
|
|
|
static const struct file_operations proc_fault_inject_operations = {
|
|
.read = proc_fault_inject_read,
|
|
.write = proc_fault_inject_write,
|
|
};
|
|
#endif
|
|
|
|
|
|
#ifdef CONFIG_SCHED_DEBUG
|
|
/*
|
|
* Print out various scheduling related per-task fields:
|
|
*/
|
|
static int sched_show(struct seq_file *m, void *v)
|
|
{
|
|
struct inode *inode = m->private;
|
|
struct task_struct *p;
|
|
|
|
WARN_ON(!inode);
|
|
|
|
p = get_proc_task(inode);
|
|
if (!p)
|
|
return -ESRCH;
|
|
proc_sched_show_task(p, m);
|
|
|
|
put_task_struct(p);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static ssize_t
|
|
sched_write(struct file *file, const char __user *buf,
|
|
size_t count, loff_t *offset)
|
|
{
|
|
struct inode *inode = file->f_path.dentry->d_inode;
|
|
struct task_struct *p;
|
|
|
|
WARN_ON(!inode);
|
|
|
|
p = get_proc_task(inode);
|
|
if (!p)
|
|
return -ESRCH;
|
|
proc_sched_set_task(p);
|
|
|
|
put_task_struct(p);
|
|
|
|
return count;
|
|
}
|
|
|
|
static int sched_open(struct inode *inode, struct file *filp)
|
|
{
|
|
int ret;
|
|
|
|
ret = single_open(filp, sched_show, NULL);
|
|
if (!ret) {
|
|
struct seq_file *m = filp->private_data;
|
|
|
|
m->private = inode;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static const struct file_operations proc_pid_sched_operations = {
|
|
.open = sched_open,
|
|
.read = seq_read,
|
|
.write = sched_write,
|
|
.llseek = seq_lseek,
|
|
.release = single_release,
|
|
};
|
|
|
|
#endif
|
|
|
|
static void *proc_pid_follow_link(struct dentry *dentry, struct nameidata *nd)
|
|
{
|
|
struct inode *inode = dentry->d_inode;
|
|
int error = -EACCES;
|
|
|
|
/* We don't need a base pointer in the /proc filesystem */
|
|
path_release(nd);
|
|
|
|
/* Are we allowed to snoop on the tasks file descriptors? */
|
|
if (!proc_fd_access_allowed(inode))
|
|
goto out;
|
|
|
|
error = PROC_I(inode)->op.proc_get_link(inode, &nd->dentry, &nd->mnt);
|
|
nd->last_type = LAST_BIND;
|
|
out:
|
|
return ERR_PTR(error);
|
|
}
|
|
|
|
static int do_proc_readlink(struct dentry *dentry, struct vfsmount *mnt,
|
|
char __user *buffer, int buflen)
|
|
{
|
|
struct inode * inode;
|
|
char *tmp = (char*)__get_free_page(GFP_TEMPORARY);
|
|
char *path;
|
|
int len;
|
|
|
|
if (!tmp)
|
|
return -ENOMEM;
|
|
|
|
inode = dentry->d_inode;
|
|
path = d_path(dentry, mnt, tmp, PAGE_SIZE);
|
|
len = PTR_ERR(path);
|
|
if (IS_ERR(path))
|
|
goto out;
|
|
len = tmp + PAGE_SIZE - 1 - path;
|
|
|
|
if (len > buflen)
|
|
len = buflen;
|
|
if (copy_to_user(buffer, path, len))
|
|
len = -EFAULT;
|
|
out:
|
|
free_page((unsigned long)tmp);
|
|
return len;
|
|
}
|
|
|
|
static int proc_pid_readlink(struct dentry * dentry, char __user * buffer, int buflen)
|
|
{
|
|
int error = -EACCES;
|
|
struct inode *inode = dentry->d_inode;
|
|
struct dentry *de;
|
|
struct vfsmount *mnt = NULL;
|
|
|
|
/* Are we allowed to snoop on the tasks file descriptors? */
|
|
if (!proc_fd_access_allowed(inode))
|
|
goto out;
|
|
|
|
error = PROC_I(inode)->op.proc_get_link(inode, &de, &mnt);
|
|
if (error)
|
|
goto out;
|
|
|
|
error = do_proc_readlink(de, mnt, buffer, buflen);
|
|
dput(de);
|
|
mntput(mnt);
|
|
out:
|
|
return error;
|
|
}
|
|
|
|
static const struct inode_operations proc_pid_link_inode_operations = {
|
|
.readlink = proc_pid_readlink,
|
|
.follow_link = proc_pid_follow_link,
|
|
.setattr = proc_setattr,
|
|
};
|
|
|
|
|
|
/* building an inode */
|
|
|
|
static int task_dumpable(struct task_struct *task)
|
|
{
|
|
int dumpable = 0;
|
|
struct mm_struct *mm;
|
|
|
|
task_lock(task);
|
|
mm = task->mm;
|
|
if (mm)
|
|
dumpable = get_dumpable(mm);
|
|
task_unlock(task);
|
|
if(dumpable == 1)
|
|
return 1;
|
|
return 0;
|
|
}
|
|
|
|
|
|
static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_struct *task)
|
|
{
|
|
struct inode * inode;
|
|
struct proc_inode *ei;
|
|
|
|
/* We need a new inode */
|
|
|
|
inode = new_inode(sb);
|
|
if (!inode)
|
|
goto out;
|
|
|
|
/* Common stuff */
|
|
ei = PROC_I(inode);
|
|
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
|
|
inode->i_op = &proc_def_inode_operations;
|
|
|
|
/*
|
|
* grab the reference to task.
|
|
*/
|
|
ei->pid = get_task_pid(task, PIDTYPE_PID);
|
|
if (!ei->pid)
|
|
goto out_unlock;
|
|
|
|
inode->i_uid = 0;
|
|
inode->i_gid = 0;
|
|
if (task_dumpable(task)) {
|
|
inode->i_uid = task->euid;
|
|
inode->i_gid = task->egid;
|
|
}
|
|
security_task_to_inode(task, inode);
|
|
|
|
out:
|
|
return inode;
|
|
|
|
out_unlock:
|
|
iput(inode);
|
|
return NULL;
|
|
}
|
|
|
|
static int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
|
|
{
|
|
struct inode *inode = dentry->d_inode;
|
|
struct task_struct *task;
|
|
generic_fillattr(inode, stat);
|
|
|
|
rcu_read_lock();
|
|
stat->uid = 0;
|
|
stat->gid = 0;
|
|
task = pid_task(proc_pid(inode), PIDTYPE_PID);
|
|
if (task) {
|
|
if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
|
|
task_dumpable(task)) {
|
|
stat->uid = task->euid;
|
|
stat->gid = task->egid;
|
|
}
|
|
}
|
|
rcu_read_unlock();
|
|
return 0;
|
|
}
|
|
|
|
/* dentry stuff */
|
|
|
|
/*
|
|
* Exceptional case: normally we are not allowed to unhash a busy
|
|
* directory. In this case, however, we can do it - no aliasing problems
|
|
* due to the way we treat inodes.
|
|
*
|
|
* Rewrite the inode's ownerships here because the owning task may have
|
|
* performed a setuid(), etc.
|
|
*
|
|
* Before the /proc/pid/status file was created the only way to read
|
|
* the effective uid of a /process was to stat /proc/pid. Reading
|
|
* /proc/pid/status is slow enough that procps and other packages
|
|
* kept stating /proc/pid. To keep the rules in /proc simple I have
|
|
* made this apply to all per process world readable and executable
|
|
* directories.
|
|
*/
|
|
static int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
|
|
{
|
|
struct inode *inode = dentry->d_inode;
|
|
struct task_struct *task = get_proc_task(inode);
|
|
if (task) {
|
|
if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
|
|
task_dumpable(task)) {
|
|
inode->i_uid = task->euid;
|
|
inode->i_gid = task->egid;
|
|
} else {
|
|
inode->i_uid = 0;
|
|
inode->i_gid = 0;
|
|
}
|
|
inode->i_mode &= ~(S_ISUID | S_ISGID);
|
|
security_task_to_inode(task, inode);
|
|
put_task_struct(task);
|
|
return 1;
|
|
}
|
|
d_drop(dentry);
|
|
return 0;
|
|
}
|
|
|
|
static int pid_delete_dentry(struct dentry * dentry)
|
|
{
|
|
/* Is the task we represent dead?
|
|
* If so, then don't put the dentry on the lru list,
|
|
* kill it immediately.
|
|
*/
|
|
return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first;
|
|
}
|
|
|
|
static struct dentry_operations pid_dentry_operations =
|
|
{
|
|
.d_revalidate = pid_revalidate,
|
|
.d_delete = pid_delete_dentry,
|
|
};
|
|
|
|
/* Lookups */
|
|
|
|
typedef struct dentry *instantiate_t(struct inode *, struct dentry *,
|
|
struct task_struct *, const void *);
|
|
|
|
/*
|
|
* Fill a directory entry.
|
|
*
|
|
* If possible create the dcache entry and derive our inode number and
|
|
* file type from dcache entry.
|
|
*
|
|
* Since all of the proc inode numbers are dynamically generated, the inode
|
|
* numbers do not exist until the inode is cache. This means creating the
|
|
* the dcache entry in readdir is necessary to keep the inode numbers
|
|
* reported by readdir in sync with the inode numbers reported
|
|
* by stat.
|
|
*/
|
|
static int proc_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
|
|
char *name, int len,
|
|
instantiate_t instantiate, struct task_struct *task, const void *ptr)
|
|
{
|
|
struct dentry *child, *dir = filp->f_path.dentry;
|
|
struct inode *inode;
|
|
struct qstr qname;
|
|
ino_t ino = 0;
|
|
unsigned type = DT_UNKNOWN;
|
|
|
|
qname.name = name;
|
|
qname.len = len;
|
|
qname.hash = full_name_hash(name, len);
|
|
|
|
child = d_lookup(dir, &qname);
|
|
if (!child) {
|
|
struct dentry *new;
|
|
new = d_alloc(dir, &qname);
|
|
if (new) {
|
|
child = instantiate(dir->d_inode, new, task, ptr);
|
|
if (child)
|
|
dput(new);
|
|
else
|
|
child = new;
|
|
}
|
|
}
|
|
if (!child || IS_ERR(child) || !child->d_inode)
|
|
goto end_instantiate;
|
|
inode = child->d_inode;
|
|
if (inode) {
|
|
ino = inode->i_ino;
|
|
type = inode->i_mode >> 12;
|
|
}
|
|
dput(child);
|
|
end_instantiate:
|
|
if (!ino)
|
|
ino = find_inode_number(dir, &qname);
|
|
if (!ino)
|
|
ino = 1;
|
|
return filldir(dirent, name, len, filp->f_pos, ino, type);
|
|
}
|
|
|
|
static unsigned name_to_int(struct dentry *dentry)
|
|
{
|
|
const char *name = dentry->d_name.name;
|
|
int len = dentry->d_name.len;
|
|
unsigned n = 0;
|
|
|
|
if (len > 1 && *name == '0')
|
|
goto out;
|
|
while (len-- > 0) {
|
|
unsigned c = *name++ - '0';
|
|
if (c > 9)
|
|
goto out;
|
|
if (n >= (~0U-9)/10)
|
|
goto out;
|
|
n *= 10;
|
|
n += c;
|
|
}
|
|
return n;
|
|
out:
|
|
return ~0U;
|
|
}
|
|
|
|
#define PROC_FDINFO_MAX 64
|
|
|
|
static int proc_fd_info(struct inode *inode, struct dentry **dentry,
|
|
struct vfsmount **mnt, char *info)
|
|
{
|
|
struct task_struct *task = get_proc_task(inode);
|
|
struct files_struct *files = NULL;
|
|
struct file *file;
|
|
int fd = proc_fd(inode);
|
|
|
|
if (task) {
|
|
files = get_files_struct(task);
|
|
put_task_struct(task);
|
|
}
|
|
if (files) {
|
|
/*
|
|
* We are not taking a ref to the file structure, so we must
|
|
* hold ->file_lock.
|
|
*/
|
|
spin_lock(&files->file_lock);
|
|
file = fcheck_files(files, fd);
|
|
if (file) {
|
|
if (mnt)
|
|
*mnt = mntget(file->f_path.mnt);
|
|
if (dentry)
|
|
*dentry = dget(file->f_path.dentry);
|
|
if (info)
|
|
snprintf(info, PROC_FDINFO_MAX,
|
|
"pos:\t%lli\n"
|
|
"flags:\t0%o\n",
|
|
(long long) file->f_pos,
|
|
file->f_flags);
|
|
spin_unlock(&files->file_lock);
|
|
put_files_struct(files);
|
|
return 0;
|
|
}
|
|
spin_unlock(&files->file_lock);
|
|
put_files_struct(files);
|
|
}
|
|
return -ENOENT;
|
|
}
|
|
|
|
static int proc_fd_link(struct inode *inode, struct dentry **dentry,
|
|
struct vfsmount **mnt)
|
|
{
|
|
return proc_fd_info(inode, dentry, mnt, NULL);
|
|
}
|
|
|
|
static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
|
|
{
|
|
struct inode *inode = dentry->d_inode;
|
|
struct task_struct *task = get_proc_task(inode);
|
|
int fd = proc_fd(inode);
|
|
struct files_struct *files;
|
|
|
|
if (task) {
|
|
files = get_files_struct(task);
|
|
if (files) {
|
|
rcu_read_lock();
|
|
if (fcheck_files(files, fd)) {
|
|
rcu_read_unlock();
|
|
put_files_struct(files);
|
|
if (task_dumpable(task)) {
|
|
inode->i_uid = task->euid;
|
|
inode->i_gid = task->egid;
|
|
} else {
|
|
inode->i_uid = 0;
|
|
inode->i_gid = 0;
|
|
}
|
|
inode->i_mode &= ~(S_ISUID | S_ISGID);
|
|
security_task_to_inode(task, inode);
|
|
put_task_struct(task);
|
|
return 1;
|
|
}
|
|
rcu_read_unlock();
|
|
put_files_struct(files);
|
|
}
|
|
put_task_struct(task);
|
|
}
|
|
d_drop(dentry);
|
|
return 0;
|
|
}
|
|
|
|
static struct dentry_operations tid_fd_dentry_operations =
|
|
{
|
|
.d_revalidate = tid_fd_revalidate,
|
|
.d_delete = pid_delete_dentry,
|
|
};
|
|
|
|
static struct dentry *proc_fd_instantiate(struct inode *dir,
|
|
struct dentry *dentry, struct task_struct *task, const void *ptr)
|
|
{
|
|
unsigned fd = *(const unsigned *)ptr;
|
|
struct file *file;
|
|
struct files_struct *files;
|
|
struct inode *inode;
|
|
struct proc_inode *ei;
|
|
struct dentry *error = ERR_PTR(-ENOENT);
|
|
|
|
inode = proc_pid_make_inode(dir->i_sb, task);
|
|
if (!inode)
|
|
goto out;
|
|
ei = PROC_I(inode);
|
|
ei->fd = fd;
|
|
files = get_files_struct(task);
|
|
if (!files)
|
|
goto out_iput;
|
|
inode->i_mode = S_IFLNK;
|
|
|
|
/*
|
|
* We are not taking a ref to the file structure, so we must
|
|
* hold ->file_lock.
|
|
*/
|
|
spin_lock(&files->file_lock);
|
|
file = fcheck_files(files, fd);
|
|
if (!file)
|
|
goto out_unlock;
|
|
if (file->f_mode & 1)
|
|
inode->i_mode |= S_IRUSR | S_IXUSR;
|
|
if (file->f_mode & 2)
|
|
inode->i_mode |= S_IWUSR | S_IXUSR;
|
|
spin_unlock(&files->file_lock);
|
|
put_files_struct(files);
|
|
|
|
inode->i_op = &proc_pid_link_inode_operations;
|
|
inode->i_size = 64;
|
|
ei->op.proc_get_link = proc_fd_link;
|
|
dentry->d_op = &tid_fd_dentry_operations;
|
|
d_add(dentry, inode);
|
|
/* Close the race of the process dying before we return the dentry */
|
|
if (tid_fd_revalidate(dentry, NULL))
|
|
error = NULL;
|
|
|
|
out:
|
|
return error;
|
|
out_unlock:
|
|
spin_unlock(&files->file_lock);
|
|
put_files_struct(files);
|
|
out_iput:
|
|
iput(inode);
|
|
goto out;
|
|
}
|
|
|
|
static struct dentry *proc_lookupfd_common(struct inode *dir,
|
|
struct dentry *dentry,
|
|
instantiate_t instantiate)
|
|
{
|
|
struct task_struct *task = get_proc_task(dir);
|
|
unsigned fd = name_to_int(dentry);
|
|
struct dentry *result = ERR_PTR(-ENOENT);
|
|
|
|
if (!task)
|
|
goto out_no_task;
|
|
if (fd == ~0U)
|
|
goto out;
|
|
|
|
result = instantiate(dir, dentry, task, &fd);
|
|
out:
|
|
put_task_struct(task);
|
|
out_no_task:
|
|
return result;
|
|
}
|
|
|
|
static int proc_readfd_common(struct file * filp, void * dirent,
|
|
filldir_t filldir, instantiate_t instantiate)
|
|
{
|
|
struct dentry *dentry = filp->f_path.dentry;
|
|
struct inode *inode = dentry->d_inode;
|
|
struct task_struct *p = get_proc_task(inode);
|
|
unsigned int fd, ino;
|
|
int retval;
|
|
struct files_struct * files;
|
|
struct fdtable *fdt;
|
|
|
|
retval = -ENOENT;
|
|
if (!p)
|
|
goto out_no_task;
|
|
retval = 0;
|
|
|
|
fd = filp->f_pos;
|
|
switch (fd) {
|
|
case 0:
|
|
if (filldir(dirent, ".", 1, 0, inode->i_ino, DT_DIR) < 0)
|
|
goto out;
|
|
filp->f_pos++;
|
|
case 1:
|
|
ino = parent_ino(dentry);
|
|
if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
|
|
goto out;
|
|
filp->f_pos++;
|
|
default:
|
|
files = get_files_struct(p);
|
|
if (!files)
|
|
goto out;
|
|
rcu_read_lock();
|
|
fdt = files_fdtable(files);
|
|
for (fd = filp->f_pos-2;
|
|
fd < fdt->max_fds;
|
|
fd++, filp->f_pos++) {
|
|
char name[PROC_NUMBUF];
|
|
int len;
|
|
|
|
if (!fcheck_files(files, fd))
|
|
continue;
|
|
rcu_read_unlock();
|
|
|
|
len = snprintf(name, sizeof(name), "%d", fd);
|
|
if (proc_fill_cache(filp, dirent, filldir,
|
|
name, len, instantiate,
|
|
p, &fd) < 0) {
|
|
rcu_read_lock();
|
|
break;
|
|
}
|
|
rcu_read_lock();
|
|
}
|
|
rcu_read_unlock();
|
|
put_files_struct(files);
|
|
}
|
|
out:
|
|
put_task_struct(p);
|
|
out_no_task:
|
|
return retval;
|
|
}
|
|
|
|
static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry,
|
|
struct nameidata *nd)
|
|
{
|
|
return proc_lookupfd_common(dir, dentry, proc_fd_instantiate);
|
|
}
|
|
|
|
static int proc_readfd(struct file *filp, void *dirent, filldir_t filldir)
|
|
{
|
|
return proc_readfd_common(filp, dirent, filldir, proc_fd_instantiate);
|
|
}
|
|
|
|
static ssize_t proc_fdinfo_read(struct file *file, char __user *buf,
|
|
size_t len, loff_t *ppos)
|
|
{
|
|
char tmp[PROC_FDINFO_MAX];
|
|
int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, NULL, tmp);
|
|
if (!err)
|
|
err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp));
|
|
return err;
|
|
}
|
|
|
|
static const struct file_operations proc_fdinfo_file_operations = {
|
|
.open = nonseekable_open,
|
|
.read = proc_fdinfo_read,
|
|
};
|
|
|
|
static const struct file_operations proc_fd_operations = {
|
|
.read = generic_read_dir,
|
|
.readdir = proc_readfd,
|
|
};
|
|
|
|
/*
|
|
* /proc/pid/fd needs a special permission handler so that a process can still
|
|
* access /proc/self/fd after it has executed a setuid().
|
|
*/
|
|
static int proc_fd_permission(struct inode *inode, int mask,
|
|
struct nameidata *nd)
|
|
{
|
|
int rv;
|
|
|
|
rv = generic_permission(inode, mask, NULL);
|
|
if (rv == 0)
|
|
return 0;
|
|
if (task_pid(current) == proc_pid(inode))
|
|
rv = 0;
|
|
return rv;
|
|
}
|
|
|
|
/*
|
|
* proc directories can do almost nothing..
|
|
*/
|
|
static const struct inode_operations proc_fd_inode_operations = {
|
|
.lookup = proc_lookupfd,
|
|
.permission = proc_fd_permission,
|
|
.setattr = proc_setattr,
|
|
};
|
|
|
|
static struct dentry *proc_fdinfo_instantiate(struct inode *dir,
|
|
struct dentry *dentry, struct task_struct *task, const void *ptr)
|
|
{
|
|
unsigned fd = *(unsigned *)ptr;
|
|
struct inode *inode;
|
|
struct proc_inode *ei;
|
|
struct dentry *error = ERR_PTR(-ENOENT);
|
|
|
|
inode = proc_pid_make_inode(dir->i_sb, task);
|
|
if (!inode)
|
|
goto out;
|
|
ei = PROC_I(inode);
|
|
ei->fd = fd;
|
|
inode->i_mode = S_IFREG | S_IRUSR;
|
|
inode->i_fop = &proc_fdinfo_file_operations;
|
|
dentry->d_op = &tid_fd_dentry_operations;
|
|
d_add(dentry, inode);
|
|
/* Close the race of the process dying before we return the dentry */
|
|
if (tid_fd_revalidate(dentry, NULL))
|
|
error = NULL;
|
|
|
|
out:
|
|
return error;
|
|
}
|
|
|
|
static struct dentry *proc_lookupfdinfo(struct inode *dir,
|
|
struct dentry *dentry,
|
|
struct nameidata *nd)
|
|
{
|
|
return proc_lookupfd_common(dir, dentry, proc_fdinfo_instantiate);
|
|
}
|
|
|
|
static int proc_readfdinfo(struct file *filp, void *dirent, filldir_t filldir)
|
|
{
|
|
return proc_readfd_common(filp, dirent, filldir,
|
|
proc_fdinfo_instantiate);
|
|
}
|
|
|
|
static const struct file_operations proc_fdinfo_operations = {
|
|
.read = generic_read_dir,
|
|
.readdir = proc_readfdinfo,
|
|
};
|
|
|
|
/*
|
|
* proc directories can do almost nothing..
|
|
*/
|
|
static const struct inode_operations proc_fdinfo_inode_operations = {
|
|
.lookup = proc_lookupfdinfo,
|
|
.setattr = proc_setattr,
|
|
};
|
|
|
|
|
|
static struct dentry *proc_pident_instantiate(struct inode *dir,
|
|
struct dentry *dentry, struct task_struct *task, const void *ptr)
|
|
{
|
|
const struct pid_entry *p = ptr;
|
|
struct inode *inode;
|
|
struct proc_inode *ei;
|
|
struct dentry *error = ERR_PTR(-EINVAL);
|
|
|
|
inode = proc_pid_make_inode(dir->i_sb, task);
|
|
if (!inode)
|
|
goto out;
|
|
|
|
ei = PROC_I(inode);
|
|
inode->i_mode = p->mode;
|
|
if (S_ISDIR(inode->i_mode))
|
|
inode->i_nlink = 2; /* Use getattr to fix if necessary */
|
|
if (p->iop)
|
|
inode->i_op = p->iop;
|
|
if (p->fop)
|
|
inode->i_fop = p->fop;
|
|
ei->op = p->op;
|
|
dentry->d_op = &pid_dentry_operations;
|
|
d_add(dentry, inode);
|
|
/* Close the race of the process dying before we return the dentry */
|
|
if (pid_revalidate(dentry, NULL))
|
|
error = NULL;
|
|
out:
|
|
return error;
|
|
}
|
|
|
|
static struct dentry *proc_pident_lookup(struct inode *dir,
|
|
struct dentry *dentry,
|
|
const struct pid_entry *ents,
|
|
unsigned int nents)
|
|
{
|
|
struct inode *inode;
|
|
struct dentry *error;
|
|
struct task_struct *task = get_proc_task(dir);
|
|
const struct pid_entry *p, *last;
|
|
|
|
error = ERR_PTR(-ENOENT);
|
|
inode = NULL;
|
|
|
|
if (!task)
|
|
goto out_no_task;
|
|
|
|
/*
|
|
* Yes, it does not scale. And it should not. Don't add
|
|
* new entries into /proc/<tgid>/ without very good reasons.
|
|
*/
|
|
last = &ents[nents - 1];
|
|
for (p = ents; p <= last; p++) {
|
|
if (p->len != dentry->d_name.len)
|
|
continue;
|
|
if (!memcmp(dentry->d_name.name, p->name, p->len))
|
|
break;
|
|
}
|
|
if (p > last)
|
|
goto out;
|
|
|
|
error = proc_pident_instantiate(dir, dentry, task, p);
|
|
out:
|
|
put_task_struct(task);
|
|
out_no_task:
|
|
return error;
|
|
}
|
|
|
|
static int proc_pident_fill_cache(struct file *filp, void *dirent,
|
|
filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
|
|
{
|
|
return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
|
|
proc_pident_instantiate, task, p);
|
|
}
|
|
|
|
static int proc_pident_readdir(struct file *filp,
|
|
void *dirent, filldir_t filldir,
|
|
const struct pid_entry *ents, unsigned int nents)
|
|
{
|
|
int i;
|
|
struct dentry *dentry = filp->f_path.dentry;
|
|
struct inode *inode = dentry->d_inode;
|
|
struct task_struct *task = get_proc_task(inode);
|
|
const struct pid_entry *p, *last;
|
|
ino_t ino;
|
|
int ret;
|
|
|
|
ret = -ENOENT;
|
|
if (!task)
|
|
goto out_no_task;
|
|
|
|
ret = 0;
|
|
i = filp->f_pos;
|
|
switch (i) {
|
|
case 0:
|
|
ino = inode->i_ino;
|
|
if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
|
|
goto out;
|
|
i++;
|
|
filp->f_pos++;
|
|
/* fall through */
|
|
case 1:
|
|
ino = parent_ino(dentry);
|
|
if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
|
|
goto out;
|
|
i++;
|
|
filp->f_pos++;
|
|
/* fall through */
|
|
default:
|
|
i -= 2;
|
|
if (i >= nents) {
|
|
ret = 1;
|
|
goto out;
|
|
}
|
|
p = ents + i;
|
|
last = &ents[nents - 1];
|
|
while (p <= last) {
|
|
if (proc_pident_fill_cache(filp, dirent, filldir, task, p) < 0)
|
|
goto out;
|
|
filp->f_pos++;
|
|
p++;
|
|
}
|
|
}
|
|
|
|
ret = 1;
|
|
out:
|
|
put_task_struct(task);
|
|
out_no_task:
|
|
return ret;
|
|
}
|
|
|
|
#ifdef CONFIG_SECURITY
|
|
static ssize_t proc_pid_attr_read(struct file * file, char __user * buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
struct inode * inode = file->f_path.dentry->d_inode;
|
|
char *p = NULL;
|
|
ssize_t length;
|
|
struct task_struct *task = get_proc_task(inode);
|
|
|
|
if (!task)
|
|
return -ESRCH;
|
|
|
|
length = security_getprocattr(task,
|
|
(char*)file->f_path.dentry->d_name.name,
|
|
&p);
|
|
put_task_struct(task);
|
|
if (length > 0)
|
|
length = simple_read_from_buffer(buf, count, ppos, p, length);
|
|
kfree(p);
|
|
return length;
|
|
}
|
|
|
|
static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
struct inode * inode = file->f_path.dentry->d_inode;
|
|
char *page;
|
|
ssize_t length;
|
|
struct task_struct *task = get_proc_task(inode);
|
|
|
|
length = -ESRCH;
|
|
if (!task)
|
|
goto out_no_task;
|
|
if (count > PAGE_SIZE)
|
|
count = PAGE_SIZE;
|
|
|
|
/* No partial writes. */
|
|
length = -EINVAL;
|
|
if (*ppos != 0)
|
|
goto out;
|
|
|
|
length = -ENOMEM;
|
|
page = (char*)__get_free_page(GFP_TEMPORARY);
|
|
if (!page)
|
|
goto out;
|
|
|
|
length = -EFAULT;
|
|
if (copy_from_user(page, buf, count))
|
|
goto out_free;
|
|
|
|
length = security_setprocattr(task,
|
|
(char*)file->f_path.dentry->d_name.name,
|
|
(void*)page, count);
|
|
out_free:
|
|
free_page((unsigned long) page);
|
|
out:
|
|
put_task_struct(task);
|
|
out_no_task:
|
|
return length;
|
|
}
|
|
|
|
static const struct file_operations proc_pid_attr_operations = {
|
|
.read = proc_pid_attr_read,
|
|
.write = proc_pid_attr_write,
|
|
};
|
|
|
|
static const struct pid_entry attr_dir_stuff[] = {
|
|
REG("current", S_IRUGO|S_IWUGO, pid_attr),
|
|
REG("prev", S_IRUGO, pid_attr),
|
|
REG("exec", S_IRUGO|S_IWUGO, pid_attr),
|
|
REG("fscreate", S_IRUGO|S_IWUGO, pid_attr),
|
|
REG("keycreate", S_IRUGO|S_IWUGO, pid_attr),
|
|
REG("sockcreate", S_IRUGO|S_IWUGO, pid_attr),
|
|
};
|
|
|
|
static int proc_attr_dir_readdir(struct file * filp,
|
|
void * dirent, filldir_t filldir)
|
|
{
|
|
return proc_pident_readdir(filp,dirent,filldir,
|
|
attr_dir_stuff,ARRAY_SIZE(attr_dir_stuff));
|
|
}
|
|
|
|
static const struct file_operations proc_attr_dir_operations = {
|
|
.read = generic_read_dir,
|
|
.readdir = proc_attr_dir_readdir,
|
|
};
|
|
|
|
static struct dentry *proc_attr_dir_lookup(struct inode *dir,
|
|
struct dentry *dentry, struct nameidata *nd)
|
|
{
|
|
return proc_pident_lookup(dir, dentry,
|
|
attr_dir_stuff, ARRAY_SIZE(attr_dir_stuff));
|
|
}
|
|
|
|
static const struct inode_operations proc_attr_dir_inode_operations = {
|
|
.lookup = proc_attr_dir_lookup,
|
|
.getattr = pid_getattr,
|
|
.setattr = proc_setattr,
|
|
};
|
|
|
|
#endif
|
|
|
|
#if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE)
|
|
static ssize_t proc_coredump_filter_read(struct file *file, char __user *buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
|
|
struct mm_struct *mm;
|
|
char buffer[PROC_NUMBUF];
|
|
size_t len;
|
|
int ret;
|
|
|
|
if (!task)
|
|
return -ESRCH;
|
|
|
|
ret = 0;
|
|
mm = get_task_mm(task);
|
|
if (mm) {
|
|
len = snprintf(buffer, sizeof(buffer), "%08lx\n",
|
|
((mm->flags & MMF_DUMP_FILTER_MASK) >>
|
|
MMF_DUMP_FILTER_SHIFT));
|
|
mmput(mm);
|
|
ret = simple_read_from_buffer(buf, count, ppos, buffer, len);
|
|
}
|
|
|
|
put_task_struct(task);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static ssize_t proc_coredump_filter_write(struct file *file,
|
|
const char __user *buf,
|
|
size_t count,
|
|
loff_t *ppos)
|
|
{
|
|
struct task_struct *task;
|
|
struct mm_struct *mm;
|
|
char buffer[PROC_NUMBUF], *end;
|
|
unsigned int val;
|
|
int ret;
|
|
int i;
|
|
unsigned long mask;
|
|
|
|
ret = -EFAULT;
|
|
memset(buffer, 0, sizeof(buffer));
|
|
if (count > sizeof(buffer) - 1)
|
|
count = sizeof(buffer) - 1;
|
|
if (copy_from_user(buffer, buf, count))
|
|
goto out_no_task;
|
|
|
|
ret = -EINVAL;
|
|
val = (unsigned int)simple_strtoul(buffer, &end, 0);
|
|
if (*end == '\n')
|
|
end++;
|
|
if (end - buffer == 0)
|
|
goto out_no_task;
|
|
|
|
ret = -ESRCH;
|
|
task = get_proc_task(file->f_dentry->d_inode);
|
|
if (!task)
|
|
goto out_no_task;
|
|
|
|
ret = end - buffer;
|
|
mm = get_task_mm(task);
|
|
if (!mm)
|
|
goto out_no_mm;
|
|
|
|
for (i = 0, mask = 1; i < MMF_DUMP_FILTER_BITS; i++, mask <<= 1) {
|
|
if (val & mask)
|
|
set_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
|
|
else
|
|
clear_bit(i + MMF_DUMP_FILTER_SHIFT, &mm->flags);
|
|
}
|
|
|
|
mmput(mm);
|
|
out_no_mm:
|
|
put_task_struct(task);
|
|
out_no_task:
|
|
return ret;
|
|
}
|
|
|
|
static const struct file_operations proc_coredump_filter_operations = {
|
|
.read = proc_coredump_filter_read,
|
|
.write = proc_coredump_filter_write,
|
|
};
|
|
#endif
|
|
|
|
/*
|
|
* /proc/self:
|
|
*/
|
|
static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
|
|
int buflen)
|
|
{
|
|
char tmp[PROC_NUMBUF];
|
|
sprintf(tmp, "%d", task_tgid_vnr(current));
|
|
return vfs_readlink(dentry,buffer,buflen,tmp);
|
|
}
|
|
|
|
static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
|
|
{
|
|
char tmp[PROC_NUMBUF];
|
|
sprintf(tmp, "%d", task_tgid_vnr(current));
|
|
return ERR_PTR(vfs_follow_link(nd,tmp));
|
|
}
|
|
|
|
static const struct inode_operations proc_self_inode_operations = {
|
|
.readlink = proc_self_readlink,
|
|
.follow_link = proc_self_follow_link,
|
|
};
|
|
|
|
/*
|
|
* proc base
|
|
*
|
|
* These are the directory entries in the root directory of /proc
|
|
* that properly belong to the /proc filesystem, as they describe
|
|
* describe something that is process related.
|
|
*/
|
|
static const struct pid_entry proc_base_stuff[] = {
|
|
NOD("self", S_IFLNK|S_IRWXUGO,
|
|
&proc_self_inode_operations, NULL, {}),
|
|
};
|
|
|
|
/*
|
|
* Exceptional case: normally we are not allowed to unhash a busy
|
|
* directory. In this case, however, we can do it - no aliasing problems
|
|
* due to the way we treat inodes.
|
|
*/
|
|
static int proc_base_revalidate(struct dentry *dentry, struct nameidata *nd)
|
|
{
|
|
struct inode *inode = dentry->d_inode;
|
|
struct task_struct *task = get_proc_task(inode);
|
|
if (task) {
|
|
put_task_struct(task);
|
|
return 1;
|
|
}
|
|
d_drop(dentry);
|
|
return 0;
|
|
}
|
|
|
|
static struct dentry_operations proc_base_dentry_operations =
|
|
{
|
|
.d_revalidate = proc_base_revalidate,
|
|
.d_delete = pid_delete_dentry,
|
|
};
|
|
|
|
static struct dentry *proc_base_instantiate(struct inode *dir,
|
|
struct dentry *dentry, struct task_struct *task, const void *ptr)
|
|
{
|
|
const struct pid_entry *p = ptr;
|
|
struct inode *inode;
|
|
struct proc_inode *ei;
|
|
struct dentry *error = ERR_PTR(-EINVAL);
|
|
|
|
/* Allocate the inode */
|
|
error = ERR_PTR(-ENOMEM);
|
|
inode = new_inode(dir->i_sb);
|
|
if (!inode)
|
|
goto out;
|
|
|
|
/* Initialize the inode */
|
|
ei = PROC_I(inode);
|
|
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
|
|
|
|
/*
|
|
* grab the reference to the task.
|
|
*/
|
|
ei->pid = get_task_pid(task, PIDTYPE_PID);
|
|
if (!ei->pid)
|
|
goto out_iput;
|
|
|
|
inode->i_uid = 0;
|
|
inode->i_gid = 0;
|
|
inode->i_mode = p->mode;
|
|
if (S_ISDIR(inode->i_mode))
|
|
inode->i_nlink = 2;
|
|
if (S_ISLNK(inode->i_mode))
|
|
inode->i_size = 64;
|
|
if (p->iop)
|
|
inode->i_op = p->iop;
|
|
if (p->fop)
|
|
inode->i_fop = p->fop;
|
|
ei->op = p->op;
|
|
dentry->d_op = &proc_base_dentry_operations;
|
|
d_add(dentry, inode);
|
|
error = NULL;
|
|
out:
|
|
return error;
|
|
out_iput:
|
|
iput(inode);
|
|
goto out;
|
|
}
|
|
|
|
static struct dentry *proc_base_lookup(struct inode *dir, struct dentry *dentry)
|
|
{
|
|
struct dentry *error;
|
|
struct task_struct *task = get_proc_task(dir);
|
|
const struct pid_entry *p, *last;
|
|
|
|
error = ERR_PTR(-ENOENT);
|
|
|
|
if (!task)
|
|
goto out_no_task;
|
|
|
|
/* Lookup the directory entry */
|
|
last = &proc_base_stuff[ARRAY_SIZE(proc_base_stuff) - 1];
|
|
for (p = proc_base_stuff; p <= last; p++) {
|
|
if (p->len != dentry->d_name.len)
|
|
continue;
|
|
if (!memcmp(dentry->d_name.name, p->name, p->len))
|
|
break;
|
|
}
|
|
if (p > last)
|
|
goto out;
|
|
|
|
error = proc_base_instantiate(dir, dentry, task, p);
|
|
|
|
out:
|
|
put_task_struct(task);
|
|
out_no_task:
|
|
return error;
|
|
}
|
|
|
|
static int proc_base_fill_cache(struct file *filp, void *dirent,
|
|
filldir_t filldir, struct task_struct *task, const struct pid_entry *p)
|
|
{
|
|
return proc_fill_cache(filp, dirent, filldir, p->name, p->len,
|
|
proc_base_instantiate, task, p);
|
|
}
|
|
|
|
#ifdef CONFIG_TASK_IO_ACCOUNTING
|
|
static int proc_pid_io_accounting(struct task_struct *task, char *buffer)
|
|
{
|
|
return sprintf(buffer,
|
|
#ifdef CONFIG_TASK_XACCT
|
|
"rchar: %llu\n"
|
|
"wchar: %llu\n"
|
|
"syscr: %llu\n"
|
|
"syscw: %llu\n"
|
|
#endif
|
|
"read_bytes: %llu\n"
|
|
"write_bytes: %llu\n"
|
|
"cancelled_write_bytes: %llu\n",
|
|
#ifdef CONFIG_TASK_XACCT
|
|
(unsigned long long)task->rchar,
|
|
(unsigned long long)task->wchar,
|
|
(unsigned long long)task->syscr,
|
|
(unsigned long long)task->syscw,
|
|
#endif
|
|
(unsigned long long)task->ioac.read_bytes,
|
|
(unsigned long long)task->ioac.write_bytes,
|
|
(unsigned long long)task->ioac.cancelled_write_bytes);
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Thread groups
|
|
*/
|
|
static const struct file_operations proc_task_operations;
|
|
static const struct inode_operations proc_task_inode_operations;
|
|
|
|
static const struct pid_entry tgid_base_stuff[] = {
|
|
DIR("task", S_IRUGO|S_IXUGO, task),
|
|
DIR("fd", S_IRUSR|S_IXUSR, fd),
|
|
DIR("fdinfo", S_IRUSR|S_IXUSR, fdinfo),
|
|
REG("environ", S_IRUSR, environ),
|
|
INF("auxv", S_IRUSR, pid_auxv),
|
|
INF("status", S_IRUGO, pid_status),
|
|
INF("limits", S_IRUSR, pid_limits),
|
|
#ifdef CONFIG_SCHED_DEBUG
|
|
REG("sched", S_IRUGO|S_IWUSR, pid_sched),
|
|
#endif
|
|
INF("cmdline", S_IRUGO, pid_cmdline),
|
|
INF("stat", S_IRUGO, tgid_stat),
|
|
INF("statm", S_IRUGO, pid_statm),
|
|
REG("maps", S_IRUGO, maps),
|
|
#ifdef CONFIG_NUMA
|
|
REG("numa_maps", S_IRUGO, numa_maps),
|
|
#endif
|
|
REG("mem", S_IRUSR|S_IWUSR, mem),
|
|
LNK("cwd", cwd),
|
|
LNK("root", root),
|
|
LNK("exe", exe),
|
|
REG("mounts", S_IRUGO, mounts),
|
|
REG("mountstats", S_IRUSR, mountstats),
|
|
#ifdef CONFIG_PROC_PAGE_MONITOR
|
|
REG("clear_refs", S_IWUSR, clear_refs),
|
|
REG("smaps", S_IRUGO, smaps),
|
|
REG("pagemap", S_IRUSR, pagemap),
|
|
#endif
|
|
#ifdef CONFIG_SECURITY
|
|
DIR("attr", S_IRUGO|S_IXUGO, attr_dir),
|
|
#endif
|
|
#ifdef CONFIG_KALLSYMS
|
|
INF("wchan", S_IRUGO, pid_wchan),
|
|
#endif
|
|
#ifdef CONFIG_SCHEDSTATS
|
|
INF("schedstat", S_IRUGO, pid_schedstat),
|
|
#endif
|
|
#ifdef CONFIG_LATENCYTOP
|
|
REG("latency", S_IRUGO, lstats),
|
|
#endif
|
|
#ifdef CONFIG_PROC_PID_CPUSET
|
|
REG("cpuset", S_IRUGO, cpuset),
|
|
#endif
|
|
#ifdef CONFIG_CGROUPS
|
|
REG("cgroup", S_IRUGO, cgroup),
|
|
#endif
|
|
INF("oom_score", S_IRUGO, oom_score),
|
|
REG("oom_adj", S_IRUGO|S_IWUSR, oom_adjust),
|
|
#ifdef CONFIG_AUDITSYSCALL
|
|
REG("loginuid", S_IWUSR|S_IRUGO, loginuid),
|
|
#endif
|
|
#ifdef CONFIG_FAULT_INJECTION
|
|
REG("make-it-fail", S_IRUGO|S_IWUSR, fault_inject),
|
|
#endif
|
|
#if defined(USE_ELF_CORE_DUMP) && defined(CONFIG_ELF_CORE)
|
|
REG("coredump_filter", S_IRUGO|S_IWUSR, coredump_filter),
|
|
#endif
|
|
#ifdef CONFIG_TASK_IO_ACCOUNTING
|
|
INF("io", S_IRUGO, pid_io_accounting),
|
|
#endif
|
|
};
|
|
|
|
static int proc_tgid_base_readdir(struct file * filp,
|
|
void * dirent, filldir_t filldir)
|
|
{
|
|
return proc_pident_readdir(filp,dirent,filldir,
|
|
tgid_base_stuff,ARRAY_SIZE(tgid_base_stuff));
|
|
}
|
|
|
|
static const struct file_operations proc_tgid_base_operations = {
|
|
.read = generic_read_dir,
|
|
.readdir = proc_tgid_base_readdir,
|
|
};
|
|
|
|
static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
|
|
return proc_pident_lookup(dir, dentry,
|
|
tgid_base_stuff, ARRAY_SIZE(tgid_base_stuff));
|
|
}
|
|
|
|
static const struct inode_operations proc_tgid_base_inode_operations = {
|
|
.lookup = proc_tgid_base_lookup,
|
|
.getattr = pid_getattr,
|
|
.setattr = proc_setattr,
|
|
};
|
|
|
|
static void proc_flush_task_mnt(struct vfsmount *mnt, pid_t pid, pid_t tgid)
|
|
{
|
|
struct dentry *dentry, *leader, *dir;
|
|
char buf[PROC_NUMBUF];
|
|
struct qstr name;
|
|
|
|
name.name = buf;
|
|
name.len = snprintf(buf, sizeof(buf), "%d", pid);
|
|
dentry = d_hash_and_lookup(mnt->mnt_root, &name);
|
|
if (dentry) {
|
|
if (!(current->flags & PF_EXITING))
|
|
shrink_dcache_parent(dentry);
|
|
d_drop(dentry);
|
|
dput(dentry);
|
|
}
|
|
|
|
if (tgid == 0)
|
|
goto out;
|
|
|
|
name.name = buf;
|
|
name.len = snprintf(buf, sizeof(buf), "%d", tgid);
|
|
leader = d_hash_and_lookup(mnt->mnt_root, &name);
|
|
if (!leader)
|
|
goto out;
|
|
|
|
name.name = "task";
|
|
name.len = strlen(name.name);
|
|
dir = d_hash_and_lookup(leader, &name);
|
|
if (!dir)
|
|
goto out_put_leader;
|
|
|
|
name.name = buf;
|
|
name.len = snprintf(buf, sizeof(buf), "%d", pid);
|
|
dentry = d_hash_and_lookup(dir, &name);
|
|
if (dentry) {
|
|
shrink_dcache_parent(dentry);
|
|
d_drop(dentry);
|
|
dput(dentry);
|
|
}
|
|
|
|
dput(dir);
|
|
out_put_leader:
|
|
dput(leader);
|
|
out:
|
|
return;
|
|
}
|
|
|
|
/**
|
|
* proc_flush_task - Remove dcache entries for @task from the /proc dcache.
|
|
* @task: task that should be flushed.
|
|
*
|
|
* When flushing dentries from proc, one needs to flush them from global
|
|
* proc (proc_mnt) and from all the namespaces' procs this task was seen
|
|
* in. This call is supposed to do all of this job.
|
|
*
|
|
* Looks in the dcache for
|
|
* /proc/@pid
|
|
* /proc/@tgid/task/@pid
|
|
* if either directory is present flushes it and all of it'ts children
|
|
* from the dcache.
|
|
*
|
|
* It is safe and reasonable to cache /proc entries for a task until
|
|
* that task exits. After that they just clog up the dcache with
|
|
* useless entries, possibly causing useful dcache entries to be
|
|
* flushed instead. This routine is proved to flush those useless
|
|
* dcache entries at process exit time.
|
|
*
|
|
* NOTE: This routine is just an optimization so it does not guarantee
|
|
* that no dcache entries will exist at process exit time it
|
|
* just makes it very unlikely that any will persist.
|
|
*/
|
|
|
|
void proc_flush_task(struct task_struct *task)
|
|
{
|
|
int i;
|
|
struct pid *pid, *tgid = NULL;
|
|
struct upid *upid;
|
|
|
|
pid = task_pid(task);
|
|
if (thread_group_leader(task))
|
|
tgid = task_tgid(task);
|
|
|
|
for (i = 0; i <= pid->level; i++) {
|
|
upid = &pid->numbers[i];
|
|
proc_flush_task_mnt(upid->ns->proc_mnt, upid->nr,
|
|
tgid ? tgid->numbers[i].nr : 0);
|
|
}
|
|
|
|
upid = &pid->numbers[pid->level];
|
|
if (upid->nr == 1)
|
|
pid_ns_release_proc(upid->ns);
|
|
}
|
|
|
|
static struct dentry *proc_pid_instantiate(struct inode *dir,
|
|
struct dentry * dentry,
|
|
struct task_struct *task, const void *ptr)
|
|
{
|
|
struct dentry *error = ERR_PTR(-ENOENT);
|
|
struct inode *inode;
|
|
|
|
inode = proc_pid_make_inode(dir->i_sb, task);
|
|
if (!inode)
|
|
goto out;
|
|
|
|
inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
|
|
inode->i_op = &proc_tgid_base_inode_operations;
|
|
inode->i_fop = &proc_tgid_base_operations;
|
|
inode->i_flags|=S_IMMUTABLE;
|
|
inode->i_nlink = 5;
|
|
#ifdef CONFIG_SECURITY
|
|
inode->i_nlink += 1;
|
|
#endif
|
|
|
|
dentry->d_op = &pid_dentry_operations;
|
|
|
|
d_add(dentry, inode);
|
|
/* Close the race of the process dying before we return the dentry */
|
|
if (pid_revalidate(dentry, NULL))
|
|
error = NULL;
|
|
out:
|
|
return error;
|
|
}
|
|
|
|
struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
|
|
{
|
|
struct dentry *result = ERR_PTR(-ENOENT);
|
|
struct task_struct *task;
|
|
unsigned tgid;
|
|
struct pid_namespace *ns;
|
|
|
|
result = proc_base_lookup(dir, dentry);
|
|
if (!IS_ERR(result) || PTR_ERR(result) != -ENOENT)
|
|
goto out;
|
|
|
|
tgid = name_to_int(dentry);
|
|
if (tgid == ~0U)
|
|
goto out;
|
|
|
|
ns = dentry->d_sb->s_fs_info;
|
|
rcu_read_lock();
|
|
task = find_task_by_pid_ns(tgid, ns);
|
|
if (task)
|
|
get_task_struct(task);
|
|
rcu_read_unlock();
|
|
if (!task)
|
|
goto out;
|
|
|
|
result = proc_pid_instantiate(dir, dentry, task, NULL);
|
|
put_task_struct(task);
|
|
out:
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* Find the first task with tgid >= tgid
|
|
*
|
|
*/
|
|
struct tgid_iter {
|
|
unsigned int tgid;
|
|
struct task_struct *task;
|
|
};
|
|
static struct tgid_iter next_tgid(struct pid_namespace *ns, struct tgid_iter iter)
|
|
{
|
|
struct pid *pid;
|
|
|
|
if (iter.task)
|
|
put_task_struct(iter.task);
|
|
rcu_read_lock();
|
|
retry:
|
|
iter.task = NULL;
|
|
pid = find_ge_pid(iter.tgid, ns);
|
|
if (pid) {
|
|
iter.tgid = pid_nr_ns(pid, ns);
|
|
iter.task = pid_task(pid, PIDTYPE_PID);
|
|
/* What we to know is if the pid we have find is the
|
|
* pid of a thread_group_leader. Testing for task
|
|
* being a thread_group_leader is the obvious thing
|
|
* todo but there is a window when it fails, due to
|
|
* the pid transfer logic in de_thread.
|
|
*
|
|
* So we perform the straight forward test of seeing
|
|
* if the pid we have found is the pid of a thread
|
|
* group leader, and don't worry if the task we have
|
|
* found doesn't happen to be a thread group leader.
|
|
* As we don't care in the case of readdir.
|
|
*/
|
|
if (!iter.task || !has_group_leader_pid(iter.task)) {
|
|
iter.tgid += 1;
|
|
goto retry;
|
|
}
|
|
get_task_struct(iter.task);
|
|
}
|
|
rcu_read_unlock();
|
|
return iter;
|
|
}
|
|
|
|
#define TGID_OFFSET (FIRST_PROCESS_ENTRY + ARRAY_SIZE(proc_base_stuff))
|
|
|
|
static int proc_pid_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
|
|
struct tgid_iter iter)
|
|
{
|
|
char name[PROC_NUMBUF];
|
|
int len = snprintf(name, sizeof(name), "%d", iter.tgid);
|
|
return proc_fill_cache(filp, dirent, filldir, name, len,
|
|
proc_pid_instantiate, iter.task, NULL);
|
|
}
|
|
|
|
/* for the /proc/ directory itself, after non-process stuff has been done */
|
|
int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
|
|
{
|
|
unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY;
|
|
struct task_struct *reaper = get_proc_task(filp->f_path.dentry->d_inode);
|
|
struct tgid_iter iter;
|
|
struct pid_namespace *ns;
|
|
|
|
if (!reaper)
|
|
goto out_no_task;
|
|
|
|
for (; nr < ARRAY_SIZE(proc_base_stuff); filp->f_pos++, nr++) {
|
|
const struct pid_entry *p = &proc_base_stuff[nr];
|
|
if (proc_base_fill_cache(filp, dirent, filldir, reaper, p) < 0)
|
|
goto out;
|
|
}
|
|
|
|
ns = filp->f_dentry->d_sb->s_fs_info;
|
|
iter.task = NULL;
|
|
iter.tgid = filp->f_pos - TGID_OFFSET;
|
|
for (iter = next_tgid(ns, iter);
|
|
iter.task;
|
|
iter.tgid += 1, iter = next_tgid(ns, iter)) {
|
|
filp->f_pos = iter.tgid + TGID_OFFSET;
|
|
if (proc_pid_fill_cache(filp, dirent, filldir, iter) < 0) {
|
|
put_task_struct(iter.task);
|
|
goto out;
|
|
}
|
|
}
|
|
filp->f_pos = PID_MAX_LIMIT + TGID_OFFSET;
|
|
out:
|
|
put_task_struct(reaper);
|
|
out_no_task:
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Tasks
|
|
*/
|
|
static const struct pid_entry tid_base_stuff[] = {
|
|
DIR("fd", S_IRUSR|S_IXUSR, fd),
|
|
DIR("fdinfo", S_IRUSR|S_IXUSR, fdinfo),
|
|
REG("environ", S_IRUSR, environ),
|
|
INF("auxv", S_IRUSR, pid_auxv),
|
|
INF("status", S_IRUGO, pid_status),
|
|
INF("limits", S_IRUSR, pid_limits),
|
|
#ifdef CONFIG_SCHED_DEBUG
|
|
REG("sched", S_IRUGO|S_IWUSR, pid_sched),
|
|
#endif
|
|
INF("cmdline", S_IRUGO, pid_cmdline),
|
|
INF("stat", S_IRUGO, tid_stat),
|
|
INF("statm", S_IRUGO, pid_statm),
|
|
REG("maps", S_IRUGO, maps),
|
|
#ifdef CONFIG_NUMA
|
|
REG("numa_maps", S_IRUGO, numa_maps),
|
|
#endif
|
|
REG("mem", S_IRUSR|S_IWUSR, mem),
|
|
LNK("cwd", cwd),
|
|
LNK("root", root),
|
|
LNK("exe", exe),
|
|
REG("mounts", S_IRUGO, mounts),
|
|
#ifdef CONFIG_PROC_PAGE_MONITOR
|
|
REG("clear_refs", S_IWUSR, clear_refs),
|
|
REG("smaps", S_IRUGO, smaps),
|
|
REG("pagemap", S_IRUSR, pagemap),
|
|
#endif
|
|
#ifdef CONFIG_SECURITY
|
|
DIR("attr", S_IRUGO|S_IXUGO, attr_dir),
|
|
#endif
|
|
#ifdef CONFIG_KALLSYMS
|
|
INF("wchan", S_IRUGO, pid_wchan),
|
|
#endif
|
|
#ifdef CONFIG_SCHEDSTATS
|
|
INF("schedstat", S_IRUGO, pid_schedstat),
|
|
#endif
|
|
#ifdef CONFIG_LATENCYTOP
|
|
REG("latency", S_IRUGO, lstats),
|
|
#endif
|
|
#ifdef CONFIG_PROC_PID_CPUSET
|
|
REG("cpuset", S_IRUGO, cpuset),
|
|
#endif
|
|
#ifdef CONFIG_CGROUPS
|
|
REG("cgroup", S_IRUGO, cgroup),
|
|
#endif
|
|
INF("oom_score", S_IRUGO, oom_score),
|
|
REG("oom_adj", S_IRUGO|S_IWUSR, oom_adjust),
|
|
#ifdef CONFIG_AUDITSYSCALL
|
|
REG("loginuid", S_IWUSR|S_IRUGO, loginuid),
|
|
#endif
|
|
#ifdef CONFIG_FAULT_INJECTION
|
|
REG("make-it-fail", S_IRUGO|S_IWUSR, fault_inject),
|
|
#endif
|
|
};
|
|
|
|
static int proc_tid_base_readdir(struct file * filp,
|
|
void * dirent, filldir_t filldir)
|
|
{
|
|
return proc_pident_readdir(filp,dirent,filldir,
|
|
tid_base_stuff,ARRAY_SIZE(tid_base_stuff));
|
|
}
|
|
|
|
static struct dentry *proc_tid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
|
|
return proc_pident_lookup(dir, dentry,
|
|
tid_base_stuff, ARRAY_SIZE(tid_base_stuff));
|
|
}
|
|
|
|
static const struct file_operations proc_tid_base_operations = {
|
|
.read = generic_read_dir,
|
|
.readdir = proc_tid_base_readdir,
|
|
};
|
|
|
|
static const struct inode_operations proc_tid_base_inode_operations = {
|
|
.lookup = proc_tid_base_lookup,
|
|
.getattr = pid_getattr,
|
|
.setattr = proc_setattr,
|
|
};
|
|
|
|
static struct dentry *proc_task_instantiate(struct inode *dir,
|
|
struct dentry *dentry, struct task_struct *task, const void *ptr)
|
|
{
|
|
struct dentry *error = ERR_PTR(-ENOENT);
|
|
struct inode *inode;
|
|
inode = proc_pid_make_inode(dir->i_sb, task);
|
|
|
|
if (!inode)
|
|
goto out;
|
|
inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
|
|
inode->i_op = &proc_tid_base_inode_operations;
|
|
inode->i_fop = &proc_tid_base_operations;
|
|
inode->i_flags|=S_IMMUTABLE;
|
|
inode->i_nlink = 4;
|
|
#ifdef CONFIG_SECURITY
|
|
inode->i_nlink += 1;
|
|
#endif
|
|
|
|
dentry->d_op = &pid_dentry_operations;
|
|
|
|
d_add(dentry, inode);
|
|
/* Close the race of the process dying before we return the dentry */
|
|
if (pid_revalidate(dentry, NULL))
|
|
error = NULL;
|
|
out:
|
|
return error;
|
|
}
|
|
|
|
static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
|
|
{
|
|
struct dentry *result = ERR_PTR(-ENOENT);
|
|
struct task_struct *task;
|
|
struct task_struct *leader = get_proc_task(dir);
|
|
unsigned tid;
|
|
struct pid_namespace *ns;
|
|
|
|
if (!leader)
|
|
goto out_no_task;
|
|
|
|
tid = name_to_int(dentry);
|
|
if (tid == ~0U)
|
|
goto out;
|
|
|
|
ns = dentry->d_sb->s_fs_info;
|
|
rcu_read_lock();
|
|
task = find_task_by_pid_ns(tid, ns);
|
|
if (task)
|
|
get_task_struct(task);
|
|
rcu_read_unlock();
|
|
if (!task)
|
|
goto out;
|
|
if (!same_thread_group(leader, task))
|
|
goto out_drop_task;
|
|
|
|
result = proc_task_instantiate(dir, dentry, task, NULL);
|
|
out_drop_task:
|
|
put_task_struct(task);
|
|
out:
|
|
put_task_struct(leader);
|
|
out_no_task:
|
|
return result;
|
|
}
|
|
|
|
/*
|
|
* Find the first tid of a thread group to return to user space.
|
|
*
|
|
* Usually this is just the thread group leader, but if the users
|
|
* buffer was too small or there was a seek into the middle of the
|
|
* directory we have more work todo.
|
|
*
|
|
* In the case of a short read we start with find_task_by_pid.
|
|
*
|
|
* In the case of a seek we start with the leader and walk nr
|
|
* threads past it.
|
|
*/
|
|
static struct task_struct *first_tid(struct task_struct *leader,
|
|
int tid, int nr, struct pid_namespace *ns)
|
|
{
|
|
struct task_struct *pos;
|
|
|
|
rcu_read_lock();
|
|
/* Attempt to start with the pid of a thread */
|
|
if (tid && (nr > 0)) {
|
|
pos = find_task_by_pid_ns(tid, ns);
|
|
if (pos && (pos->group_leader == leader))
|
|
goto found;
|
|
}
|
|
|
|
/* If nr exceeds the number of threads there is nothing todo */
|
|
pos = NULL;
|
|
if (nr && nr >= get_nr_threads(leader))
|
|
goto out;
|
|
|
|
/* If we haven't found our starting place yet start
|
|
* with the leader and walk nr threads forward.
|
|
*/
|
|
for (pos = leader; nr > 0; --nr) {
|
|
pos = next_thread(pos);
|
|
if (pos == leader) {
|
|
pos = NULL;
|
|
goto out;
|
|
}
|
|
}
|
|
found:
|
|
get_task_struct(pos);
|
|
out:
|
|
rcu_read_unlock();
|
|
return pos;
|
|
}
|
|
|
|
/*
|
|
* Find the next thread in the thread list.
|
|
* Return NULL if there is an error or no next thread.
|
|
*
|
|
* The reference to the input task_struct is released.
|
|
*/
|
|
static struct task_struct *next_tid(struct task_struct *start)
|
|
{
|
|
struct task_struct *pos = NULL;
|
|
rcu_read_lock();
|
|
if (pid_alive(start)) {
|
|
pos = next_thread(start);
|
|
if (thread_group_leader(pos))
|
|
pos = NULL;
|
|
else
|
|
get_task_struct(pos);
|
|
}
|
|
rcu_read_unlock();
|
|
put_task_struct(start);
|
|
return pos;
|
|
}
|
|
|
|
static int proc_task_fill_cache(struct file *filp, void *dirent, filldir_t filldir,
|
|
struct task_struct *task, int tid)
|
|
{
|
|
char name[PROC_NUMBUF];
|
|
int len = snprintf(name, sizeof(name), "%d", tid);
|
|
return proc_fill_cache(filp, dirent, filldir, name, len,
|
|
proc_task_instantiate, task, NULL);
|
|
}
|
|
|
|
/* for the /proc/TGID/task/ directories */
|
|
static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir)
|
|
{
|
|
struct dentry *dentry = filp->f_path.dentry;
|
|
struct inode *inode = dentry->d_inode;
|
|
struct task_struct *leader = NULL;
|
|
struct task_struct *task;
|
|
int retval = -ENOENT;
|
|
ino_t ino;
|
|
int tid;
|
|
unsigned long pos = filp->f_pos; /* avoiding "long long" filp->f_pos */
|
|
struct pid_namespace *ns;
|
|
|
|
task = get_proc_task(inode);
|
|
if (!task)
|
|
goto out_no_task;
|
|
rcu_read_lock();
|
|
if (pid_alive(task)) {
|
|
leader = task->group_leader;
|
|
get_task_struct(leader);
|
|
}
|
|
rcu_read_unlock();
|
|
put_task_struct(task);
|
|
if (!leader)
|
|
goto out_no_task;
|
|
retval = 0;
|
|
|
|
switch (pos) {
|
|
case 0:
|
|
ino = inode->i_ino;
|
|
if (filldir(dirent, ".", 1, pos, ino, DT_DIR) < 0)
|
|
goto out;
|
|
pos++;
|
|
/* fall through */
|
|
case 1:
|
|
ino = parent_ino(dentry);
|
|
if (filldir(dirent, "..", 2, pos, ino, DT_DIR) < 0)
|
|
goto out;
|
|
pos++;
|
|
/* fall through */
|
|
}
|
|
|
|
/* f_version caches the tgid value that the last readdir call couldn't
|
|
* return. lseek aka telldir automagically resets f_version to 0.
|
|
*/
|
|
ns = filp->f_dentry->d_sb->s_fs_info;
|
|
tid = (int)filp->f_version;
|
|
filp->f_version = 0;
|
|
for (task = first_tid(leader, tid, pos - 2, ns);
|
|
task;
|
|
task = next_tid(task), pos++) {
|
|
tid = task_pid_nr_ns(task, ns);
|
|
if (proc_task_fill_cache(filp, dirent, filldir, task, tid) < 0) {
|
|
/* returning this tgid failed, save it as the first
|
|
* pid for the next readir call */
|
|
filp->f_version = (u64)tid;
|
|
put_task_struct(task);
|
|
break;
|
|
}
|
|
}
|
|
out:
|
|
filp->f_pos = pos;
|
|
put_task_struct(leader);
|
|
out_no_task:
|
|
return retval;
|
|
}
|
|
|
|
static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
|
|
{
|
|
struct inode *inode = dentry->d_inode;
|
|
struct task_struct *p = get_proc_task(inode);
|
|
generic_fillattr(inode, stat);
|
|
|
|
if (p) {
|
|
rcu_read_lock();
|
|
stat->nlink += get_nr_threads(p);
|
|
rcu_read_unlock();
|
|
put_task_struct(p);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct inode_operations proc_task_inode_operations = {
|
|
.lookup = proc_task_lookup,
|
|
.getattr = proc_task_getattr,
|
|
.setattr = proc_setattr,
|
|
};
|
|
|
|
static const struct file_operations proc_task_operations = {
|
|
.read = generic_read_dir,
|
|
.readdir = proc_task_readdir,
|
|
};
|