resolved: fix loop on packets with pseudo dns types

Reported by Karim Hossen & Thomas Imbert from Sogeti ESEC R&D.

https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1725351

diff --git a/src/resolve/resolved-dns-packet.c b/src/resolve/resolved-dns-packet.c
index e2f227bfc64c84d4f75fc3fbdc3c2ab39145894d..35f4d0689b29c365018f223d7c076b90b00a81ab 100644 (file)
--- a/src/resolve/resolved-dns-packet.c
+++ b/src/resolve/resolved-dns-packet.c
@@ -1514,7 +1514,7 @@ static int dns_packet_read_type_window(DnsPacket *p, Bitmap **types, size_t *sta
 
                 found = true;
 
-                while (bitmask) {
+                for (; bitmask; bit++, bitmask >>= 1)
                         if (bitmap[i] & bitmask) {
                                 uint16_t n;
 
@@ -1528,10 +1528,6 @@ static int dns_packet_read_type_window(DnsPacket *p, Bitmap **types, size_t *sta
                                 if (r < 0)
                                         return r;
                         }
-
-                        bit++;
-                        bitmask >>= 1;
-                }
         }
 
         if (!found)