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);
--
2.27.0
