From: zhengbin <zhengbin13@xxxxxxxxxx> [ Upstream commit e26cc08265dda37d2acc8394604f220ef412299d ] 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@xxxxxxxxxxxxxxx Reviewed-by: Ming Lei <ming.lei@xxxxxxxxxx> Signed-off-by: zhengbin <zhengbin13@xxxxxxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- block/blk-mq.c | 2 -- block/blk-sysfs.c | 3 +++ 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/block/blk-mq.c b/block/blk-mq.c index 9dfafee65bce2..7ea85ec52026e 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2461,8 +2461,6 @@ void blk_mq_release(struct request_queue *q) struct blk_mq_hw_ctx *hctx; unsigned int i; - cancel_delayed_work_sync(&q->requeue_work); - /* hctx kobj stays in hctx */ queue_for_each_hw_ctx(q, hctx, i) { if (!hctx) diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index 3772671cf2bc5..bab47a17b96f4 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -836,6 +836,9 @@ static void __blk_release_queue(struct work_struct *work) blk_free_queue_stats(q->stats); + if (q->mq_ops) + cancel_delayed_work_sync(&q->requeue_work); + blk_exit_rl(q, &q->root_rl); if (q->queue_tags) -- 2.20.1