wait_task_stopped(): don't use task_pid_nr_ns() lockless
authorOleg Nesterov <oleg@tv-sign.ru>
Thu, 29 Nov 2007 00:21:24 +0000 (16:21 -0800)
committerLinus Torvalds <torvalds@woody.linux-foundation.org>
Thu, 29 Nov 2007 17:24:52 +0000 (09:24 -0800)
commitc895078355b6b6e05c60aa205892526dd3390f0a
tree922a0b9204b0cfcd5c59762f4d02e167d587ccd2
parentc2319540cd7330fa9066e5b9b84d357a2c8631a2
wait_task_stopped(): don't use task_pid_nr_ns() lockless

wait_task_stopped(WNOWAIT) does task_pid_nr_ns() without tasklist/rcu lock,
we can read an already freed memory.  Use the cached pid_t value.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Looks-good-to: Roland McGrath <roland@redhat.com>
Acked-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kernel/exit.c