timesyncd: consider too long packets as invalid

If the received NTP message from server didn't fit to our buffer, either
it is doing something nasty or we don't know the protocol. Consider the
packet as invalid.

(David: add parantheses around conditional)

diff --git a/src/timesync/timesyncd-manager.c b/src/timesync/timesyncd-manager.c
index 117ea8c98d83c495edb043e566951a5a7f25603f..bc35662481fb5d4b958cc929666c72a3e71ca5f9 100644 (file)
--- a/src/timesync/timesyncd-manager.c
+++ b/src/timesync/timesyncd-manager.c
@@ -525,7 +525,8 @@ static int manager_receive_response(sd_event_source *source, int fd, uint32_t re
                 return manager_connect(m);
         }
 
-        if (iov.iov_len < sizeof(struct ntp_msg)) {
+        /* Too short or too long packet? */
+        if (iov.iov_len < sizeof(struct ntp_msg) || (msghdr.msg_flags & MSG_TRUNC)) {
                 log_warning("Invalid response from server. Disconnecting.");
                 return manager_connect(m);
         }