On Sat, Jul 31, 2021 at 09:50 PM CEST, Cong Wang wrote:
> From: Cong Wang <cong.wang@xxxxxxxxxxxxx>
>
> As of now, only AF_UNIX datagram socket supports sockmap.
> But unix_proto is shared for all kinds of AF_UNIX sockets,
> so we have to check the socket type in
> unix_bpf_update_proto() to explicitly reject other types,
> otherwise they could be added into sockmap too.
>
> Fixes: c63829182c37 ("af_unix: Implement ->psock_update_sk_prot()")
> Reported-by: Jakub Sitnicki <jakub@xxxxxxxxxxxxxx>
> Cc: John Fastabend <john.fastabend@xxxxxxxxx>
> Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
> Cc: Lorenz Bauer <lmb@xxxxxxxxxxxxxx>
> Signed-off-by: Cong Wang <cong.wang@xxxxxxxxxxxxx>
> ---
> net/unix/unix_bpf.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/net/unix/unix_bpf.c b/net/unix/unix_bpf.c
> index 177e883f451e..20f53575b5c9 100644
> --- a/net/unix/unix_bpf.c
> +++ b/net/unix/unix_bpf.c
> @@ -105,6 +105,9 @@ static void unix_bpf_check_needs_rebuild(struct proto *ops)
>
> int unix_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore)
> {
> + if (sk->sk_type != SOCK_DGRAM)
> + return -EOPNOTSUPP;
> +
> if (restore) {
> sk->sk_write_space = psock->saved_write_space;
> WRITE_ONCE(sk->sk_prot, psock->sk_proto);
Acked-by: Jakub Sitnicki <jakub@xxxxxxxxxxxxxx>
