diff --git a/src/dawn_native/d3d12/CommandBufferD3D12.cpp b/src/dawn_native/d3d12/CommandBufferD3D12.cpp
index 91b2f61793..0d8d83aaa5 100644
--- a/src/dawn_native/d3d12/CommandBufferD3D12.cpp
+++ b/src/dawn_native/d3d12/CommandBufferD3D12.cpp
@@ -230,11 +230,15 @@ namespace dawn_native { namespace d3d12 {
             uint32_t bytesPerRow =
                 Align(blockInfo.byteSize * widthInBlocks, kTextureBytesPerRowAlignment);
             uint32_t rowsPerImage = heightInBlocks;
-            uint64_t tempBufferSize = bytesPerRow * (widthInBlocks * heightInBlocks - 1) +
-                                      Align(blockInfo.byteSize * widthInBlocks, 4);
+
+            // The size of temporary buffer isn't needed to be a multiple of 4 because we don't
+            // need to set mappedAtCreation to be true.
+            auto tempBufferSize =
+                ComputeRequiredBytesInCopy(blockInfo, copySize, bytesPerRow, rowsPerImage);
+
             BufferDescriptor tempBufferDescriptor;
             tempBufferDescriptor.usage = wgpu::BufferUsage::CopySrc | wgpu::BufferUsage::CopyDst;
-            tempBufferDescriptor.size = tempBufferSize;
+            tempBufferDescriptor.size = tempBufferSize.AcquireSuccess();
             Device* device = ToBackend(srcCopy.texture->GetDevice());
             Ref<Buffer> tempBuffer =
                 AcquireRef(ToBackend(device->CreateBuffer(&tempBufferDescriptor)));
diff --git a/src/tests/end2end/CopyTests.cpp b/src/tests/end2end/CopyTests.cpp
index 05e85a586f..f6d6a3dad3 100644
--- a/src/tests/end2end/CopyTests.cpp
+++ b/src/tests/end2end/CopyTests.cpp
@@ -1628,13 +1628,17 @@ TEST_P(CopyTests_T2T, CopyFromNonZeroMipLevelWithTexelBlockSizeLessThan4Bytes) {
     ASSERT_LE(kSrcSize, kTextureBytesPerRowAlignment);
     ASSERT_LE(kDstSize, kTextureBytesPerRowAlignment);
 
+    // The copyDepth to test:
+    // 1u (non-array texture), 3u (copyDepth < copyWidth), 5u (copyDepth > copyWidth)
+    constexpr std::array<uint32_t, 3> kTestTextureDepth = {1u, 3u, 5u};
+
     for (wgpu::TextureFormat format : kFormats) {
         if (HasToggleEnabled("disable_snorm_read") &&
             (format == wgpu::TextureFormat::RG8Snorm || format == wgpu::TextureFormat::R8Snorm)) {
             continue;
         }
 
-        for (uint32_t textureDepth = 1; textureDepth < 3; ++textureDepth) {
+        for (uint32_t textureDepth : kTestTextureDepth) {
             const wgpu::Extent3D kUploadSize = {4u, 4u, textureDepth};
 
             for (uint32_t srcLevel = 0; srcLevel < kSrcLevelCount; ++srcLevel) {