lib/resolve: don't append EDNS to garbage packets

The current handler will try to construct the compression table
starting with query name in question. If there's no query name,
it's going to construct it with garbage bytes.

diff --git a/lib/resolve.c b/lib/resolve.c
index d18a9284a4b1d64a1bd82606f2d24cbbcd51e4b3..af1f317f23efed102fc64a4ca462b8b83606cd0d 100644 (file)
--- a/lib/resolve.c
+++ b/lib/resolve.c
@@ -383,7 +383,8 @@ static int ns_resolve_addr(struct kr_query *qry, struct kr_request *param)
 
 static int edns_put(knot_pkt_t *pkt)
 {
-       if (!pkt->opt_rr) {
+       /* Don't append EDNS to garbage packets */
+       if (!pkt->opt_rr || knot_pkt_qname(pkt) == NULL) {
                return kr_ok();
        }
        /* Reclaim reserved size. */