Split the overflow check into explicit multiplication and addition overflow checks.

src/common/version.h

 #define MAJOR_VERSION 1
 #define MINOR_VERSION 2
 #define BUILD_VERSION 0
-#define BUILD_REVISION 2433
+#define BUILD_REVISION 2434
 
 #define STRINGIFY(x) #x
 #define MACRO_STRINGIFY(x) STRINGIFY(x)

src/libGLESv2/renderer/IndexDataManager.cpp

@@ -140,9 +140,9 @@ GLenum IndexDataManager::prepareIndexData(GLenum type, GLsizei count, gl::Buffer
 
         unsigned int typeSize = gl::ComputeTypeSize(type);
 
-        // check for integer overflows and underflows
-        if (static_cast<unsigned int>(offset) > (std::numeric_limits<unsigned int>::max() / typeSize) ||
-            static_cast<unsigned int>(count) > ((std::numeric_limits<unsigned int>::max() / typeSize) - offset))
+        // check for integer overflows
+        if (static_cast<unsigned int>(count) > (std::numeric_limits<unsigned int>::max() / typeSize) ||
+            typeSize * static_cast<unsigned int>(count) + offset < offset)
         {
             return GL_OUT_OF_MEMORY;
         }