tree a19972027792082fed505c8d540f7d877e37c0ab
parent 1c0d04c9e44f4a248335c33d2be7c7f7b06ff359
author Oleg Nesterov <oleg@tv-sign.ru> 1159780739 -0700
committer Linus Torvalds <torvalds@g5.osdl.org> 1159801045 -0700

[PATCH] introduce get_task_pid() to fix unsafe get_pid()

proc_pid_make_inode:

	ei->pid = get_pid(task_pid(task));

I think this is not safe.  get_pid() can be preempted after checking "pid
!= NULL".  Then the task exits, does detach_pid(), and RCU frees the pid.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>