proc: io_accounting: Use new infrastructure to fix deadlocks in execve
This changes do_io_accounting to use the new exec_update_mutex
instead of cred_guard_mutex.
This fixes possible deadlocks when the trace is accessing
/proc/$pid/io for instance.
This should be safe, as the credentials are only used for reading.
Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
diff --git a/fs/proc/base.c b/fs/proc/base.c
index a278fda..74f948a 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -2883,7 +2883,7 @@ static int do_io_accounting(struct task_struct *task, struct seq_file *m, int wh
unsigned long flags;
int result;
- result = mutex_lock_killable(&task->signal->cred_guard_mutex);
+ result = mutex_lock_killable(&task->signal->exec_update_mutex);
if (result)
return result;
@@ -2919,7 +2919,7 @@ static int do_io_accounting(struct task_struct *task, struct seq_file *m, int wh
result = 0;
out_unlock:
- mutex_unlock(&task->signal->cred_guard_mutex);
+ mutex_unlock(&task->signal->exec_update_mutex);
return result;
}