From: Ian Jackson <Ian.Jackson@eu.citrix.com>
Date: Thu, 13 Dec 2012 11:44:01 +0000 (+0000)
Subject: libxl: qemu trad logdirty: Tolerate ENOENT on ret path
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~7525
X-Git-Url: https://dgit.raspbian.org/%22http:/www.example.com/cgi/%22https:/%22bookmarks://%22/%22http:/www.example.com/cgi/%22https:/%22bookmarks:/%22?a=commitdiff_plain;h=b051ddb41617ba543ee8de5cfc3258a0a2b71aa6;p=xen.git

libxl: qemu trad logdirty: Tolerate ENOENT on ret path

It can happen in error conditions that lds->ret_path doesn't exist,
and libxl__xs_read_checked signals this by setting got_ret=NULL.  If
this happens, fail without crashing.

Reported-by: Alex Bligh <alex@alex.org.uk>,
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>
---

diff --git a/tools/libxl/libxl_dom.c b/tools/libxl/libxl_dom.c
index 95da18e560..7586a6c97c 100644
--- a/tools/libxl/libxl_dom.c
+++ b/tools/libxl/libxl_dom.c
@@ -725,7 +725,7 @@ static void domain_suspend_switch_qemu_xen_traditional_logdirty
             rc = libxl__xs_read_checked(gc, t, lds->ret_path, &got_ret);
             if (rc) goto out;
 
-            if (strcmp(got, got_ret)) {
+            if (!got_ret || strcmp(got, got_ret)) {
                 LOG(ERROR,"controlling logdirty: qemu was already sent"
                     " command `%s' (xenstore path `%s') but result is `%s'",
                     got, lds->cmd_path, got_ret ? got_ret : "<none>");