| Message ID | 1565613415-24807-1-git-send-email-zhengbin13@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | blk-mq: move cancel of requeue_work to the front of blk_exit_queue | expand |
On Mon, Aug 12, 2019 at 08:36:55PM +0800, zhengbin wrote: > 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") > Signed-off-by: zhengbin <zhengbin13@huawei.com> > --- > 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 f78d328..a8e6a58 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 977c659..9bfa3ea 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); Looks fine: Reviewed-by: Ming Lei <ming.lei@redhat.com> Thanks, Ming
On 8/12/19 5:36 AM, zhengbin wrote: > 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 Applied, thanks.
diff --git a/block/blk-mq.c b/block/blk-mq.c index f78d328..a8e6a58 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 977c659..9bfa3ea 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);
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") Signed-off-by: zhengbin <zhengbin13@huawei.com> --- block/blk-mq.c | 2 -- block/blk-sysfs.c | 3 +++ 2 files changed, 3 insertions(+), 2 deletions(-) -- 2.7.4