zebra: interface name must be a valid string

Validate incoming netlink interface name strings.

Signed-off-by: Mark Stapp <mjs.ietf@gmail.com>

diff --git a/zebra/if_netlink.c b/zebra/if_netlink.c
index a51e0b82cb28bbb1062b4f9b08e996ccc1349c0d..2a9fff26661c80f79bd34ec6c05717506a60ef62 100644 (file)
--- a/zebra/if_netlink.c
+++ b/zebra/if_netlink.c
@@ -1527,6 +1527,14 @@ int netlink_link_change(struct nlmsghdr *h, ns_id_t ns_id, int startup)
                return -1;
        name = (char *)RTA_DATA(tb[IFLA_IFNAME]);
 
+       /* Must be valid string. */
+       len = RTA_PAYLOAD(tb[IFLA_IFNAME]);
+       if (len < 2 || name[len - 1] != '\0') {
+               if (IS_ZEBRA_DEBUG_KERNEL)
+                       zlog_debug("%s: invalid intf name", __func__);
+               return -1;
+       }
+
        if (tb[IFLA_LINKINFO]) {
                netlink_parse_rtattr_nested(linkinfo, IFLA_INFO_MAX,
                                            tb[IFLA_LINKINFO]);