From 26ba2d214376ba0ebcf8b1b0dedca2fb5fb5733a Mon Sep 17 00:00:00 2001
From: Topi Miettinen <toiwoton@gmail.com>
Date: Sun, 18 Jan 2015 16:01:25 +0200
Subject: [PATCH] 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)

(cherry picked from commit 43fcd650e5cb0836cfc9f667ed74b3bc0283a81c)
---
 src/timesync/timesyncd-manager.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/timesync/timesyncd-manager.c b/src/timesync/timesyncd-manager.c
index 3ae01eb8fc..7c5632b776 100644
--- a/src/timesync/timesyncd-manager.c
+++ b/src/timesync/timesyncd-manager.c
@@ -534,7 +534,8 @@ 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);
         }