From: Tycho Andersen <tycho.andersen@canonical.com>
Date: Fri, 6 May 2016 16:21:39 +0000 (-0500)
Subject: sync: fail on unexpected message sizes
X-Git-Tag: lxc-2.1.0~430^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=refs%2Fpull%2F1005%2Fhead;p=thirdparty%2Flxc.git

sync: fail on unexpected message sizes

I think (?) this may be related to our hanging monitor bug. Let's do this
anyway, as it's probably a good idea.

Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
---

diff --git a/src/lxc/sync.c b/src/lxc/sync.c
index f06d302f7..82f68e364 100644
--- a/src/lxc/sync.c
+++ b/src/lxc/sync.c
@@ -47,6 +47,11 @@ static int __sync_wait(int fd, int sequence)
 	if (!ret)
 		return 0;
 
+	if (ret != sizeof(sync)) {
+		ERROR("unexpected sync size: %d expected %lu", ret, sizeof(sync));
+		return -1;
+	}
+
 	if (sync == LXC_SYNC_ERROR) {
 		ERROR("An error occurred in another process "
 		      "(expected sequence number %d)", sequence);