| Message ID | 20201009080015.3217-1-yang.yang@vivo.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | blk-mq: move cancel of hctx->run_work to the front of blk_exit_queue | expand |
On Fri, Oct 09, 2020 at 01:00:14AM -0700, Yang Yang wrote: > 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@vivo.com> > --- > 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); > + } > + Looks fine: Reviewed-by: Ming Lei <ming.lei@redhat.com> Thanks, Ming
On 10/9/20 2:00 AM, Yang Yang wrote: > 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. Applied, thanks.
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);
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@vivo.com> --- block/blk-mq-sysfs.c | 2 -- block/blk-sysfs.c | 9 ++++++++- 2 files changed, 8 insertions(+), 3 deletions(-)