Re: [PATCH v2] blk-mq: fix null pointer dereference in blk_mq_clear_rq_mapping()

[Jens Axboe]

On Tue, 11 Oct 2022 22:22:53 +0800, Yu Kuai wrote:
> From: Yu Kuai <yukuai3@xxxxxxxxxx>
> 
> Our syzkaller report a null pointer dereference, root cause is
> following:
> 
> __blk_mq_alloc_map_and_rqs
>  set->tags[hctx_idx] = blk_mq_alloc_map_and_rqs
>   blk_mq_alloc_map_and_rqs
>    blk_mq_alloc_rqs
>     // failed due to oom
>     alloc_pages_node
>     // set->tags[hctx_idx] is still NULL
>     blk_mq_free_rqs
>      drv_tags = set->tags[hctx_idx];
>      // null pointer dereference is triggered
>      blk_mq_clear_rq_mapping(drv_tags, ...)
> 
> [...]

Applied, thanks!

[1/1] blk-mq: fix null pointer dereference in blk_mq_clear_rq_mapping()
      commit: 76dd298094f484c6250ebd076fa53287477b2328

Best regards,
-- 
Jens Axboe