test: static/socket-tcp -- Check if unshare successed

Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Andrei Vagin <avagin@virtuozzo.com>

test/zdtm/static/socket-tcp.c

@@ -68,7 +68,10 @@ int main(int argc, char **argv)
 	socklen_t optlen;
 
 #ifdef ZDTM_CONNTRACK
-	unshare(CLONE_NEWNET);
+	if (unshare(CLONE_NEWNET)) {
+		pr_perror("unshare");
+		return 1;
+	}
 	if (system("ip link set up dev lo"))
 		return 1;
 	if (system("iptables -w -A INPUT -i lo -p tcp -m state --state NEW,ESTABLISHED -j ACCEPT"))