Commit 4ee86bab authored Mar 15, 2016 by Hannes Reinecke Committed by Jens Axboe Mar 15, 2016

blk-mq: add bounds check on tag-to-rq conversion



We need to check for a valid index before accessing the array
element to avoid accessing invalid memory regions.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>

Modified by Jens to drop the unlikely(), and make the fall through
path be having a valid tag.

Signed-off-by: Jens Axboe <axboe@fb.com>

parent 2b885517

block/blk-mq.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -544,7 +544,10 @@ EXPORT_SYMBOL(blk_mq_abort_requeue_list);

		struct request blk_mq_tag_to_rq(struct blk_mq_tags tags, unsigned int tag)
		{
		if (tag < tags->nr_tags)
		return tags->rqs[tag];

		return NULL;
		}
		EXPORT_SYMBOL(blk_mq_tag_to_rq);