resolve: do not hit CNAME or DNAME entry in NODATA cache (systemd#9836)

Fixes systemd#9833.
andir · Aug 13, 2018 · 3740146 · 3740146
1 parent 5d3bab7
commit 3740146
Showing 1 changed file with 2 additions and 2 deletions.
diff --git a/src/resolve/resolved-dns-cache.c b/src/resolve/resolved-dns-cache.c
@@ -783,7 +783,7 @@ static DnsCacheItem *dns_cache_get_by_key_follow_cname_dname_nsec(DnsCache *c, D
         if (dns_type_may_redirect(k->type)) {
                 /* Check if we have a CNAME record instead */
                 i = hashmap_get(c->by_key, &DNS_RESOURCE_KEY_CONST(k->class, DNS_TYPE_CNAME, n));
-                if (i)
+                if (i && i->type != DNS_CACHE_NODATA)
                         return i;
 
                 /* OK, let's look for cached DNAME records. */
@@ -792,7 +792,7 @@ static DnsCacheItem *dns_cache_get_by_key_follow_cname_dname_nsec(DnsCache *c, D
                                 return NULL;
 
                         i = hashmap_get(c->by_key, &DNS_RESOURCE_KEY_CONST(k->class, DNS_TYPE_DNAME, n));
-                        if (i)
+                        if (i && i->type != DNS_CACHE_NODATA)
                                 return i;
 
                         /* Jump one label ahead */