On Sun, Jul 07, 2024 at 11:28 PM +02, Michal Luczaj wrote:
> AF_UNIX socket tracks the most recent OOB packet (in its receive queue)
> with an `oob_skb` pointer. BPF redirecting does not account for that: when
> an OOB packet is moved between sockets, `oob_skb` is left outdated. This
> results in a single skb that may be accessed from two different sockets.
>
> Take the easy way out: silently drop MSG_OOB data targeting any socket that
> is in a sockmap or a sockhash. Note that such silent drop is akin to the
> fate of redirected skb's scm_fp_list (SCM_RIGHTS, SCM_CREDENTIALS).
>
> For symmetry, forbid MSG_OOB in unix_bpf_recvmsg().
>
> Suggested-by: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx>
> Fixes: 314001f0bf92 ("af_unix: Add OOB support")
> Signed-off-by: Michal Luczaj <mhal@xxxxxxx>
> ---
Reviewed-by: Jakub Sitnicki <jakub@xxxxxxxxxxxxxx>
