block: fix use-after-free bug in blk throttle code
authorJens Axboe <jaxboe@fusionio.com>
Sat, 23 Oct 2010 18:40:26 +0000 (20:40 +0200)
committerJens Axboe <jaxboe@fusionio.com>
Sat, 23 Oct 2010 18:40:26 +0000 (20:40 +0200)
commit7ad58c028652753814054f4e3ac58f925e7343f4
tree2e3bc1c5e3c98078b970483cd49a49d7c1ae0dcf
parent7f3883962870dd28b5f2322ac44a9d03640ef448
block: fix use-after-free bug in blk throttle code

blk_throtl_exit() frees the throttle data hanging off the queue
in blk_cleanup_queue(), but blk_put_queue() will indirectly
dereference this data when calling blk_sync_queue() which in
turns calls throtl_shutdown_timer_wq().

Fix this by moving the freeing of the throttle data to when
the queue is truly being released, and post the call to
blk_sync_queue().

Reported-by: Ingo Molnar <mingo@elte.hu>
Tested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
block/blk-core.c
block/blk-sysfs.c