Re: [PATCH net] net/sched: act_api: use mutex in tcf_idr_check_alloc

[Victor Nogueira]

On 26/05/2026 19:08, Kyle Zeng wrote:
> Currently, the NEWTFILTER path uses RCU to guard action idr accesses while
> the DELTFILTER path uses mutex to guard action accesses. This
> inconsistency leads to a race condition scenario, which can lead to
> erroneous operations on refcount, eventually leading to use-after-free
> situation.
> In this patch, we revert the introduction of RCU back to mutex in the
> NEWFILTER path, which is consistent with the DELFILTER path, avoiding
> the race condition.
>
> Fixes: 4b55e86736d5 ("net/sched: act_api: rely on rcu in tcf_idr_check_alloc")
> Signed-off-by: Kyle Zeng <kylebot@xxxxxxxxxx>

Reviewed-by: Victor Nogueira <victor@xxxxxxxxxxxx>