diff options
author | KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> | 2010-10-27 18:34:08 -0400 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-10-27 21:03:12 -0400 |
commit | 9b1bf12d5d51bca178dea21b04a0805e29d60cf1 (patch) | |
tree | 902a2c0e5882a2152da59a589958d6426dc84643 /fs/proc | |
parent | b84011508360d6885a9d95a235ec77d56f133377 (diff) |
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) | |||
226 | { | 226 | { |
227 | struct mm_struct *mm; | 227 | struct mm_struct *mm; |
228 | 228 | ||
229 | if (mutex_lock_killable(&task->cred_guard_mutex)) | 229 | if (mutex_lock_killable(&task->signal->cred_guard_mutex)) |
230 | return NULL; | 230 | return NULL; |
231 | 231 | ||
232 | mm = get_task_mm(task); | 232 | mm = get_task_mm(task); |
@@ -235,7 +235,7 @@ struct mm_struct *mm_for_maps(struct task_struct *task) | |||
235 | mmput(mm); | 235 | mmput(mm); |
236 | mm = NULL; | 236 | mm = NULL; |
237 | } | 237 | } |
238 | mutex_unlock(&task->cred_guard_mutex); | 238 | mutex_unlock(&task->signal->cred_guard_mutex); |
239 | 239 | ||
240 | return mm; | 240 | return mm; |
241 | } | 241 | } |
@@ -2354,14 +2354,14 @@ static ssize_t proc_pid_attr_write(struct file * file, const char __user * buf, | |||
2354 | goto out_free; | 2354 | goto out_free; |
2355 | 2355 | ||
2356 | /* Guard against adverse ptrace interaction */ | 2356 | /* Guard against adverse ptrace interaction */ |
2357 | length = mutex_lock_interruptible(&task->cred_guard_mutex); | 2357 | length = mutex_lock_interruptible(&task->signal->cred_guard_mutex); |
2358 | if (length < 0) | 2358 | if (length < 0) |
2359 | goto out_free; | 2359 | goto out_free; |
2360 | 2360 | ||
2361 | length = security_setprocattr(task, | 2361 | length = security_setprocattr(task, |
2362 | (char*)file->f_path.dentry->d_name.name, | 2362 | (char*)file->f_path.dentry->d_name.name, |
2363 | (void*)page, count); | 2363 | (void*)page, count); |
2364 | mutex_unlock(&task->cred_guard_mutex); | 2364 | mutex_unlock(&task->signal->cred_guard_mutex); |
2365 | out_free: | 2365 | out_free: |
2366 | free_page((unsigned long) page); | 2366 | free_page((unsigned long) page); |
2367 | out: | 2367 | out: |