dns: Fix segfault with mixed ipv4/ipv6 nameservers

Follow-up on bug #1154432.

diff --git a/dns.c b/dns.c
index 8ea48ba915eb2be075e5ad40c446f4a4cd88753f..371934ffbec220a8510fbc0f161f43a113711755 100644 (file)
--- a/dns.c
+++ b/dns.c
@@ -1334,6 +1334,9 @@ void dns_ack6(void)
     if ( addrcmp( (void *) &(from6->sin6_addr), (void *) &localhost6,
                   (int) AF_INET6 ) == 0 ) {
       for (i = 0;i < NSCOUNT6;i++) {
+        if (!NSSOCKADDR6(i))
+          continue;
+
        if ( addrcmp( (void *) &(NSSOCKADDR6(i)->sin6_addr),
                      (void *) &(from6->sin6_addr), (int) AF_INET6 ) == 0 ||
             addrcmp( (void *) &(NSSOCKADDR6(i)->sin6_addr),