diff options
| author | KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> | 2010-10-28 00:34:08 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-10-28 03:03:12 +0200 |
| commit | 9b1bf12d5d51bca178dea21b04a0805e29d60cf1 (patch) | |
| tree | 902a2c0e5882a2152da59a589958d6426dc84643 /fs/proc | |
| parent | signals: annotate lock context change on ptrace_stop() (diff) | |
| download | linux-9b1bf12d5d51bca178dea21b04a0805e29d60cf1.tar.xz linux-9b1bf12d5d51bca178dea21b04a0805e29d60cf1.zip | |
signals: move cred_guard_mutex from task_struct to signal_struct
Oleg Nesterov pointed out we have to prevent multiple-threads-inside-exec
itself and we can reuse ->cred_guard_mutex for it. Yes, concurrent
execve() has no worth.
Let's move ->cred_guard_mutex from task_struct to signal_struct. It
naturally prevent multiple-threads-inside-exec.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/proc')
| -rw-r--r-- | fs/proc/base.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/fs/proc/base.c b/fs/proc/base.c index 9b094c1c8465..f3d02ca461ec 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -226,7 +226,7 @@ struct mm_struct *mm_for_maps(struct task_struct *task) { struct mm_struct *mm; - if (mutex_lock_killable(&task->cred_guard_mutex)) + if (mutex_lock_killable(&task->signal->cred_guard_mutex)) return NULL; mm = get_task_mm(task); @@ -235,7 +235,7 @@ struct mm_struct *mm_for_maps(struct task_struct *task) mmput(mm); mm = NULL; } - mutex_unlock(&task->cred_guard_mutex); + mutex_unlock(&task->signal->cred_guard_mutex); return mm; } @@ -2354,14 +2354,14 @@ static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, goto out_free; /* Guard against adverse ptrace interaction */ - length = mutex_lock_interruptible(&task->cred_guard_mutex); + length = mutex_lock_interruptible(&task->signal->cred_guard_mutex); if (length < 0) goto out_free; length = security_setprocattr(task, (char*)file->f_path.dentry->d_name.name, (void*)page, count); - mutex_unlock(&task->cred_guard_mutex); + mutex_unlock(&task->signal->cred_guard_mutex); out_free: free_page((unsigned long) page); out: |