Xiaomeng Tong <xiam0nd.tong@xxxxxxxxx> wrote:
> If the previous list_for_each_entry_continue_rcu() don't exit early
> (no goto hit inside the loop), the iterator 'cvif' after the loop
> will be a bogus pointer to an invalid structure object containing
> the HEAD (&ar->vif_list). As a result, the use of 'cvif' after that
> will lead to a invalid memory access (i.e., 'cvif->id': the invalid
> pointer dereference when return back to/after the callsite in the
> carl9170_update_beacon()).
>
> The original intention should have been to return the valid 'cvif'
> when found in list, NULL otherwise. So just return NULL when no
> entry found, to fix this bug.
>
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: 1f1d9654e183c ("carl9170: refactor carl9170_update_beacon")
> Signed-off-by: Xiaomeng Tong <xiam0nd.tong@xxxxxxxxx>
> Acked-by: Christian Lamparter <chunkeey@xxxxxxxxx>
> Signed-off-by: Kalle Valo <quic_kvalo@xxxxxxxxxxx>
Patch applied to ath-next branch of ath.git, thanks.
54a6f29522da carl9170: tx: fix an incorrect use of list iterator
--
https://patchwork.kernel.org/project/linux-wireless/patch/20220328122820.1004-1-xiam0nd.tong@xxxxxxxxx/
https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
