config: check for invalid DNS addresses

[oweals/odhcpd.git] / src / config.c

diff --git a/src/config.c b/src/config.c
index 9ae8466991f7c8ec53b0bffcdd2a845a050d53b0..9ffe1ac14123b2c0d64882d2fa61ea4093676d50 100644 (file)
--- a/src/config.c
+++ b/src/config.c
@@ -580,6 +580,9 @@ int config_parse_interface(void *data, size_t len, const char *name, bool overwr
                        struct in_addr addr4;
                        struct in6_addr addr6;
                        if (inet_pton(AF_INET, blobmsg_get_string(cur), &addr4) == 1) {
+                               if (addr4.s_addr == INADDR_ANY)
+                                       goto err;
+
                                iface->dhcpv4_dns = realloc(iface->dhcpv4_dns,
                                                (++iface->dhcpv4_dns_cnt) * sizeof(*iface->dhcpv4_dns));
                                if (!iface->dhcpv4_dns)
@@ -587,6 +590,9 @@ int config_parse_interface(void *data, size_t len, const char *name, bool overwr
 
                                iface->dhcpv4_dns[iface->dhcpv4_dns_cnt - 1] = addr4;
                        } else if (inet_pton(AF_INET6, blobmsg_get_string(cur), &addr6) == 1) {
+                               if (IN6_IS_ADDR_UNSPECIFIED(&addr6))
+                                       goto err;
+
                                iface->dns = realloc(iface->dns,
                                                (++iface->dns_cnt) * sizeof(*iface->dns));
                                if (!iface->dns)