Minor fixes

Source/Engine/GraphicsDevice/Vulkan/GPUContextVulkan.cpp

@@ -1388,7 +1388,7 @@ void GPUContextVulkan::UpdateBuffer(GPUBuffer* buffer, const void* data, uint32
     }
     else
     {
-        auto allocation = _device->UploadBuffer.Upload(data, size, 4);
+        auto allocation = _device->UploadBuffer.Upload(data, size, PLATFORM_MEMORY_ALIGNMENT);
 
         VkBufferCopy region;
         region.size = size;

Source/Engine/GraphicsDevice/Vulkan/UploadBufferVulkan.cpp

@@ -111,6 +111,7 @@ UploadBufferVulkan::Allocation UploadBufferVulkan::Allocate(uint64 size, uint64
 
     // Move within a page
     _currentOffset += size;
+    ASSERT_LOW_LAYER(_currentOffset <= _currentPage->Size);
 
     return result;
 }