This is a note to let you know that I've just added the patch titled
net/x25: Fix to not accept on connected socket
to the 6.1-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
net-x25-fix-to-not-accept-on-connected-socket.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit c6213128a4c27d43d5201b77f7381a89dfb651e7
Author: Hyunwoo Kim <v4bel@xxxxxxxxx>
Date: Mon Jan 23 11:43:23 2023 -0800
net/x25: Fix to not accept on connected socket
[ Upstream commit f2b0b5210f67c56a3bcdf92ff665fb285d6e0067 ]
When listen() and accept() are called on an x25 socket
that connect() succeeds, accept() succeeds immediately.
This is because x25_connect() queues the skb to
sk->sk_receive_queue, and x25_accept() dequeues it.
This creates a child socket with the sk of the parent
x25 socket, which can cause confusion.
Fix x25_listen() to return -EINVAL if the socket has
already been successfully connect()ed to avoid this issue.
Signed-off-by: Hyunwoo Kim <v4bel@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/net/x25/af_x25.c b/net/x25/af_x25.c
index 3b55502b2965..5c7ad301d742 100644
--- a/net/x25/af_x25.c
+++ b/net/x25/af_x25.c
@@ -482,6 +482,12 @@ static int x25_listen(struct socket *sock, int backlog)
int rc = -EOPNOTSUPP;
lock_sock(sk);
+ if (sock->state != SS_UNCONNECTED) {
+ rc = -EINVAL;
+ release_sock(sk);
+ return rc;
+ }
+
if (sk->sk_state != TCP_LISTEN) {
memset(&x25_sk(sk)->dest_addr, 0, X25_ADDR_LEN);
sk->sk_max_ack_backlog = backlog;
