From e26cc08265dda37d2acc8394604f220ef412299d Mon Sep 17 00:00:00 2001 From: zhengbin Date: Mon, 12 Aug 2019 20:36:55 +0800 Subject: blk-mq: move cancel of requeue_work to the front of blk_exit_queue blk_exit_queue will free elevator_data, while blk_mq_requeue_work will access it. Move cancel of requeue_work to the front of blk_exit_queue to avoid use-after-free. blk_exit_queue blk_mq_requeue_work __elevator_exit blk_mq_run_hw_queues blk_mq_exit_sched blk_mq_run_hw_queue dd_exit_queue blk_mq_hctx_has_pending kfree(elevator_data) blk_mq_sched_has_work dd_has_work Fixes: fbc2a15e3433 ("blk-mq: move cancel of requeue_work into blk_mq_release") Cc: stable@vger.kernel.org Reviewed-by: Ming Lei Signed-off-by: zhengbin Signed-off-by: Jens Axboe --- block/blk-mq.c | 2 -- block/blk-sysfs.c | 3 +++ 2 files changed, 3 insertions(+), 2 deletions(-) (limited to 'block') diff --git a/block/blk-mq.c b/block/blk-mq.c index f78d3287dd82..a8e6a58f5f28 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2666,8 +2666,6 @@ void blk_mq_release(struct request_queue *q) struct blk_mq_hw_ctx *hctx, *next; int i; - cancel_delayed_work_sync(&q->requeue_work); - queue_for_each_hw_ctx(q, hctx, i) WARN_ON_ONCE(hctx && list_empty(&hctx->hctx_list)); diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 977c659dcd18..9bfa3ea4ed63 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -892,6 +892,9 @@ static void __blk_release_queue(struct work_struct *work) blk_free_queue_stats(q->stats); + if (queue_is_mq(q)) + cancel_delayed_work_sync(&q->requeue_work); + blk_exit_queue(q); blk_queue_free_zone_bitmaps(q); -- cgit v1.2.3-55-g7522