blk-mq: move cancel of hctx->run_work to the front of blk_exit_queue (47ce030b) · Commits · 戴 / test

blk_exit_queue will free elevator_data, while blk_mq_run_work_fn will access it. Move cancel of hctx->run_work to the front of blk_exit_queue to avoid use-after-free. Fixes: ("blk-mq: move cancel of hctx->run_work into blk_mq_hw_sysfs_release") Signed-off-by:

Yang Yang <yang.yang@vivo.com> Reviewed-by:

Ming Lei <ming.lei@redhat.com> Signed-off-by:

Jens Axboe <axboe@kernel.dk>

block/blk-mq-sysfs.c

+0 −2

Original line number	Diff line number	Diff line
		@@ -36,8 +36,6 @@ static void blk_mq_hw_sysfs_release(struct kobject *kobj)
		struct blk_mq_hw_ctx *hctx = container_of(kobj, struct blk_mq_hw_ctx,
		kobj);

		cancel_delayed_work_sync(&hctx->run_work);

		if (hctx->flags & BLK_MQ_F_BLOCKING)
		cleanup_srcu_struct(hctx->srcu);
		blk_free_flush_queue(hctx->fq);

block/blk-sysfs.c

+8 −1

Original line number	Diff line number	Diff line
		@@ -790,9 +790,16 @@ static void blk_release_queue(struct kobject *kobj)

		blk_free_queue_stats(q->stats);

		if (queue_is_mq(q))
		if (queue_is_mq(q)) {
		struct blk_mq_hw_ctx *hctx;
		int i;

		cancel_delayed_work_sync(&q->requeue_work);

		queue_for_each_hw_ctx(q, hctx, i)
		cancel_delayed_work_sync(&hctx->run_work);
		}

		blk_exit_queue(q);

		blk_queue_free_zone_bitmaps(q);

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