From: Ming Lei <tom.leiming@gmail.com>
Date: Thu, 5 Dec 2013 17:50:39 +0000 (-0700)
Subject: blk-mq: fix use-after-free of request
X-Git-Tag: upstream/snapshot3+hdmi~3827^2
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=0d11e6aca396e679c07b2dd6af5dc8b7f041fbbd;p=platform%2Fadaptation%2Frenesas_rcar%2Frenesas_kernel.git

blk-mq: fix use-after-free of request

If accounting is on, we will do the IO completion accounting after
we have freed the request. Fix that by moving it sooner instead.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 70fd6f9..c79126e 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -312,12 +312,12 @@ void blk_mq_complete_request(struct request *rq, int error)
 
 	blk_account_io_completion(rq, bytes);
 
+	blk_account_io_done(rq);
+
 	if (rq->end_io)
 		rq->end_io(rq, error);
 	else
 		blk_mq_free_request(rq);
-
-	blk_account_io_done(rq);
 }
 
 void __blk_mq_end_io(struct request *rq, int error)