commit 10b94a6b89a8a409cd268d306aeb313aac5deb45
author Shahbaz Youssefi <syoussefi@google.com> Wed Jan 09 23:00:15 2019 -0500
committer Mark Lobodzinski <mark@lunarg.com> Thu Jan 10 08:56:26 2019 -0700
tree 1352eec9193052e8356a40d82ebfc6a31364156f
parent e8b824755f2d3f08049315d514b893d8533c837f

Fix a crash with unbalanced debug markers

If there are more End markers than Begin markers at any time, the vector
that keeps track of the labels will issue a `pop_back()` while being
empty, causing a crash.

This was observed on ANGLE's Vulkan backend executing deqp test
dEQP.GLES2/functional_debug_marker_random.

layers/vk_layer_logging.h

diff --git a/layers/vk_layer_logging.h b/layers/vk_layer_logging.h
index 6096e23..13e8c5a 100644
--- a/layers/vk_layer_logging.h
+++ b/layers/vk_layer_logging.h
@@ -1162,8 +1162,11 @@
             report_data->cmdBufLabelHasInsert = false;
             label_iter->second.pop_back();
         }
-        // Now pop the normal item
-        label_iter->second.pop_back();
+        // Guard against unbalanced markers.
+        if (label_iter->second.size() > 0) {
+            // Now pop the normal item
+            label_iter->second.pop_back();
+        }
     }
 }