resolved: explicitly refuse adding invalid DNS names to DNS packets

Fixes: systemd#33671 (cherry picked from commit e637856)
bluca · Nov 13, 2024 · c18b1ad · c18b1ad
1 parent 5b3dd2d
commit c18b1ad
Showing 1 changed file with 6 additions and 0 deletions.
diff --git a/src/resolve/resolved-dns-packet.c b/src/resolve/resolved-dns-packet.c
@@ -564,6 +564,12 @@ int dns_packet_append_name(
         assert(p);
         assert(name);
 
+        r = dns_name_is_valid(name);
+        if (r < 0)
+                return r;
+        if (r == 0)
+                return -EINVAL;
+
         if (p->refuse_compression)
                 allow_compression = false;