From: zhengbin Date: Mon, 12 Aug 2019 12:36:55 +0000 (+0800) Subject: blk-mq: move cancel of requeue_work to the front of blk_exit_queue X-Git-Tag: Ubuntu-4.15.0-67.76~299 X-Git-Url: https://git.proxmox.com/?p=mirror_ubuntu-bionic-kernel.git;a=commitdiff_plain;h=84607af9cc4739ee4c89dd854f451ac94dbe368d blk-mq: move cancel of requeue_work to the front of blk_exit_queue BugLink: https://bugs.launchpad.net/bugs/1847155 [ 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@vger.kernel.org Reviewed-by: Ming Lei Signed-off-by: zhengbin Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin Signed-off-by: Kamal Mostafa Signed-off-by: Kleber Sacilotto de Souza --- diff --git a/block/blk-mq.c b/block/blk-mq.c index 4af46c103754..a8d26b68c752 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2395,8 +2395,6 @@ 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 870484eaed1f..f1d563997d0e 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -808,6 +808,9 @@ 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)