QTextEngine::LayoutData::reallocate musn't corrupt memory

... on re-allocation failure. So, let's actually check the returned
pointer and fail, instead of using Q_CHECK_PTR.

Task-number: QT-3785
Reviewed-by: Peter Hartmann
Reviewed-by: Samuel Rødal

1 files changed, 5 insertions, 2 deletions

diff --git a/src/gui/text/qtextengine.cpp b/src/gui/text/qtextengine.cpp
index c30091e..119217a 100644
--- a/src/gui/text/qtextengine.cpp
+++ b/src/gui/text/qtextengine.cpp
@@ -2139,8 +2139,11 @@ bool QTextEngine::LayoutData::reallocate(int totalGlyphs)
 
     void **newMem = memory;
     newMem = (void **)::realloc(memory_on_stack ? 0 : memory, newAllocated*sizeof(void *));
-    Q_CHECK_PTR(newMem);
-    if (memory_on_stack && newMem)
+    if (!newMem) {
+        layoutState = LayoutFailed;
+        return false;
+    }
+    if (memory_on_stack)
         memcpy(newMem, memory, allocated*sizeof(void *));
     memory = newMem;
     memory_on_stack = false;