Subject: Re: [PATCH net v5 1/2] net: sched: fix use-after-free in taprio_change()

From: Vinicius Costa Gomes <[email-masked]>
Date: Thu, 05 Sep 2024 09:43:49 -0300

Dmitry Antipov <[email-masked]> writes:

> In 'taprio_change()', 'admin' pointer may become dangling due to sched
> switch / removal caused by 'advance_sched()', and critical section
> protected by 'q->current_entry_lock' is too small to prevent from such
> a scenario (which causes use-after-free detected by KASAN). Fix this
> by prefer 'rcu_replace_pointer()' over 'rcu_assign_pointer()' to update
> 'admin' immediately before an attempt to schedule freeing.
>
> Fixes: a3d43c0d56f1 ("taprio: Add support adding an admin schedule")
> Reported-by: [email-masked]
> Closes: https://syzkaller.appspot.com/bug?extid=b65e0af58423fc8a73aa
> Signed-off-by: Dmitry Antipov <[email-masked]>
> ---
> v5: unchanged since v4 but resend due to series change
> v4: adjust subject to target net tree
> v3: unchanged since v2
> v2: unchanged since v1
> ---

Acked-by: Vinicius Costa Gomes <[email-masked]>

Cheers,
-- 
Vinicius