Re: [PATCH] io_uring: Fix use-after-free in io_sq_wq_submit_work()

Jens Axboe
2020-08-05T19:14:47Z

On 8/4/20 9:40 PM, Guoyu Huang wrote:
> when ctx->sqo_mm is zero, io_sq_wq_submit_work() frees 'req'
> without deleting it from 'task_list'. After that, 'req' is
> accessed in io_ring_ctx_wait_and_kill() which lead to
> a use-after-free.

This looks like an old one, that affects 5.4 only. I've massaged
it to apply on top of another fix, will ask to get it queued up for
stable. Thanks!

--
Jens Axboe