[libvirt] [PATCH] tests: utils: Fix out-of-bounds access to memory in virTestCompareToFile

[Peter Krempa]

Similarly to 3506f1ecfde, the contents of 'cmpcontent' may be an empty
string so the following code would access memory out of the array.

Signed-off-by: Peter Krempa <pkrempa at redhat.com>
---
 tests/testutils.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tests/testutils.c b/tests/testutils.c
index 4bd1b63755..7c095caac9 100644
--- a/tests/testutils.c
+++ b/tests/testutils.c
@@ -797,10 +797,11 @@ virTestCompareToFile(const char *strcontent,

     if (filecontent) {
         size_t filecontentLen = strlen(filecontent);
+        size_t cmpcontentLen = strlen(cmpcontent);

         if (filecontentLen > 0 &&
             filecontent[filecontentLen - 1] == '\n' &&
-            cmpcontent[strlen(cmpcontent) - 1] != '\n') {
+            (cmpcontentLen == 0 || cmpcontent[cmpcontentLen - 1] != '\n')) {
             if (virAsprintf(&fixedcontent, "%s\n", cmpcontent) < 0)
                 goto failure;
             cmpcontent = fixedcontent;
-- 
2.16.2