Handle the "no local address" case in send_sptps_data().
authorEtienne Dechamps <etienne@edechamps.fr>
Sat, 12 Jul 2014 10:06:36 +0000 (11:06 +0100)
committerGuus Sliepen <guus@tinc-vpn.org>
Sat, 12 Jul 2014 12:17:59 +0000 (14:17 +0200)
If choose_local_address() is unable to find a local address (e.g.
because of old nodes that don't send their local address information),
then send_sptps_data() ends up using uninitialized variables for the
socket and address.

This regression was introduced in
415910897122da0073a862784d148802ca390020. The commit took care of
handling that case in send_udppacket() but was missing the same fix
for send_sptps_data().

This bug was found by the clang static analyzer tool:
http://clang-analyzer.llvm.org/

src/net_packet.c

index 6b3183d..609b452 100644 (file)
@@ -769,12 +769,12 @@ bool send_sptps_data(void *handle, uint8_t type, const char *data, size_t len) {
 
        /* Otherwise, send the packet via UDP */
 
-       const sockaddr_t *sa;
+       const sockaddr_t *sa = NULL;
        int sock;
 
        if(to->status.send_locally)
                choose_local_address(to, &sa, &sock);
-       else
+       if(!sa)
                choose_udp_address(to, &sa, &sock);
 
        if(sendto(listen_socket[sock].udp.fd, data, len, 0, &sa->sa, SALEN(sa->sa)) < 0 && !sockwouldblock(sockerrno)) {