Re: [PATCH] block, bfq: fix uaf for 'stable_merge_bfqq'

From: Jens Axboe
Date: Wed Mar 08 2023 - 09:35:45 EST



On Wed, 08 Mar 2023 10:32:08 +0800, Yu Kuai wrote:
> Before commit fd571df0ac5b ("block, bfq: turn bfqq_data into an array
> in bfq_io_cq"), process reference is read before bfq_put_stable_ref(),
> and it's safe if bfq_put_stable_ref() put the last reference, because
> process reference will be 0 and 'stable_merge_bfqq' won't be accessed
> in this case. However, the commit changed the order and will cause
> uaf for 'stable_merge_bfqq'.
>
> [...]

Applied, thanks!

[1/1] block, bfq: fix uaf for 'stable_merge_bfqq'
commit: e2f2a39452c43b64ea3191642a2661cb8d03827a

Best regards,
--
Jens Axboe