inet: Ensure data->channel exist before accessing it

Log of segfault:
...
connmand[676]: src/network.c:check_dhcpv6() reply (nil)
connmand[676]: src/network.c:check_dhcpv6() re-send router solicitation 3
connmand[676]: src/inet.c:__connman_inet_ipv6_send_rs()
connmand[676]: Aborting (signal 11) [connmand]

diff --git a/src/inet.c b/src/inet.c
index d9e12a9..220ea14 100644 (file)
--- a/src/inet.c
+++ b/src/inet.c
@@ -1433,9 +1433,11 @@ static const struct in6_addr in6addr_all_routers_mc =
 
 static void rs_cleanup(struct rs_cb_data *data)
 {
-       g_io_channel_shutdown(data->channel, TRUE, NULL);
-       g_io_channel_unref(data->channel);
-       data->channel = 0;
+       if (data->channel != NULL) {
+               g_io_channel_shutdown(data->channel, TRUE, NULL);
+               g_io_channel_unref(data->channel);
+               data->channel = NULL;
+       }
 
        if (data->rs_timeout > 0)
                g_source_remove(data->rs_timeout);