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: 1b97871b501f ("blk-mq: move cancel of hctx->run_work into blk_mq_hw_sysfs_release")
Signed-off-by: Yang Yang <yang.yang@xxxxxxxx>
---
block/blk-mq-sysfs.c | 2 --
block/blk-sysfs.c | 9 ++++++++-
2 files changed, 8 insertions(+), 3 deletions(-)
diff --git a/block/blk-mq-sysfs.c b/block/blk-mq-sysfs.c
index 062229395a50..7b52e7657b2d 100644
--- a/block/blk-mq-sysfs.c
+++ b/block/blk-mq-sysfs.c
@@ -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);
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index 7dda709f3ccb..8c6bafc801dd 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -934,9 +934,16 @@ 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);
--
2.17.1
