dco: fix crash when --multihome is used with --proto tcp

Although it's a combination of options that is not really useful, when specifying --multihome along with --proto tcp and DCO is enabled, OpenVPN will crash while attempting to access c2.link_socket_actual (NULL for the TCP case) in order to retrieve the local address (in function dco_multi_get_localaddr()) Prevent crash by running this code only if proto is UDP. The same check is already performed in socket.c/h for the non-DCO case. Github: fixes #390 Change-Id: I61adc26ce2ff737e020c3d980902a46758cb23e5 Signed-off-by: Antonio Quartulli <[email protected]> Acked-by: Gert Doering <[email protected]> Message-Id: <[email protected]> URL: https://www.mail-archive.com/[email protected]/msg26953.html Signed-off-by: Gert Doering <[email protected]>
OpenVPN · Sep 10, 2023 · 0793eb1 · 0793eb1
1 parent 34bf473
commit 0793eb1
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/src/openvpn/dco.c b/src/openvpn/dco.c
@@ -509,7 +509,7 @@ dco_multi_get_localaddr(struct multi_context *m, struct multi_instance *mi,
 #if ENABLE_IP_PKTINFO
     struct context *c = &mi->context;
 
-    if (!(c->options.sockflags & SF_USE_IP_PKTINFO))
+    if (!proto_is_udp(c->c2.link_socket->info.proto) || !(c->options.sockflags & SF_USE_IP_PKTINFO))
     {
         return false;
     }