From 83f31535565c63ac4f62c7b8592210929a630d3d Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Sat, 31 Jul 2021 12:50:38 -0700 Subject: [PATCH] bpf, unix: Check socket type in unix_bpf_update_proto() 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 Signed-off-by: Cong Wang Signed-off-by: Daniel Borkmann Acked-by: Jakub Sitnicki Link: https://lore.kernel.org/bpf/20210731195038.8084-1-xiyou.wangcong@gmail.com --- 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);