mptcp: avoid bogus reset on fallback close

Since the blamed commit, the MPTCP protocol unconditionally sends TCP resets on all the subflows on disconnect(). That fits full-blown MPTCP sockets - to implement the fastclose mechanism - but causes unexpected corruption of the data stream, catched as sporadic self-tests failures. Fixes: d21f834 ("mptcp: use fastclose on more edge scenarios") Tested-by: Matthieu Baerts <[email protected]> Closes: multipath-tcp/mptcp_net-next#419 Signed-off-by: Paolo Abeni <[email protected]>
intel-lab-lkp · Jul 27, 2023 · 7fbd5f4 · 7fbd5f4
1 parent f374771
commit 7fbd5f4
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
@@ -2346,7 +2346,7 @@ static void __mptcp_close_ssk(struct sock *sk, struct sock *ssk,
 
 	lock_sock_nested(ssk, SINGLE_DEPTH_NESTING);
 
-	if (flags & MPTCP_CF_FASTCLOSE) {
+	if ((flags & MPTCP_CF_FASTCLOSE) && !__mptcp_check_fallback(msk)) {
 		/* be sure to force the tcp_disconnect() path,
 		 * to generate the egress reset
 		 */