diff options
author | Jeff Moyer <jmoyer@redhat.com> | 2013-12-04 01:23:00 +0400 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2013-12-04 01:24:28 +0400 |
commit | 959a35f13eb785f982d79b1aaa75872d05c821da (patch) | |
tree | cf6d053aee1a645f5ec9fc8e81d5f153b5a8692d | |
parent | e345d767f6530ec9cb0aabab7ea248072a9c6975 (diff) | |
download | linux-959a35f13eb785f982d79b1aaa75872d05c821da.tar.xz |
blk-mq: fix dereference of rq->mq_ctx if allocation fails
If __GFP_WAIT isn't set and we fail allocating, when we go
to drop the reference on the ctx, we will attempt to dereference
the NULL rq. Fix that.
Signed-off-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-rw-r--r-- | block/blk-mq.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/block/blk-mq.c b/block/blk-mq.c index cdc629cf075b..70fd6f996600 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -202,10 +202,12 @@ static struct request *blk_mq_alloc_request_pinned(struct request_queue *q, if (rq) { blk_mq_rq_ctx_init(q, ctx, rq, rw); break; - } else if (!(gfp & __GFP_WAIT)) - break; + } blk_mq_put_ctx(ctx); + if (!(gfp & __GFP_WAIT)) + break; + __blk_mq_run_hw_queue(hctx); blk_mq_wait_for_tags(hctx->tags); } while (1); @@ -222,7 +224,8 @@ struct request *blk_mq_alloc_request(struct request_queue *q, int rw, return NULL; rq = blk_mq_alloc_request_pinned(q, rw, gfp, reserved); - blk_mq_put_ctx(rq->mq_ctx); + if (rq) + blk_mq_put_ctx(rq->mq_ctx); return rq; } @@ -235,7 +238,8 @@ struct request *blk_mq_alloc_reserved_request(struct request_queue *q, int rw, return NULL; rq = blk_mq_alloc_request_pinned(q, rw, gfp, true); - blk_mq_put_ctx(rq->mq_ctx); + if (rq) + blk_mq_put_ctx(rq->mq_ctx); return rq; } EXPORT_SYMBOL(blk_mq_alloc_reserved_request); |