interfaces: handle the case where the provided MAC address is incorrect

Some drivers, like veth are unable to provide an appropriate MAC
address. Warn the user, keep the one we have.

diff --git a/src/daemon/interfaces-linux.c b/src/daemon/interfaces-linux.c
index afad6485258beb2aa7a14b12913d38a03bfda63b..733d49fe2d181cf4ebe6b4ff7a6f3b8fbffbe936 100644 (file)
--- a/src/daemon/interfaces-linux.c
+++ b/src/daemon/interfaces-linux.c
@@ -252,6 +252,14 @@ iflinux_get_permanent_mac(struct lldpd *cfg,
                    iface->name);
                return;
        }
+       size_t i;
+       for (i = 0; i < ETHER_ADDR_LEN; i++)
+               if (mac[i] != 0) break;
+       if (i == ETHER_ADDR_LEN) {
+               log_warnx("interfaces", "driver for %s do not provide a permanent MAC address",
+                   iface->name);
+               return;
+       }
        memcpy(iface->address, mac,
            ETHER_ADDR_LEN);
 }