fixup! fix(core): validate start + size for buffer ops in more places

Author: ErichDonGubler

wgpu-core/src/command/transfer.rs

@@ -351,7 +351,7 @@ pub(crate) fn validate_linear_texture_data(
         return Err(TransferError::UnspecifiedRowsPerImage);
     };
 
-    if offset >= buffer_size {
+    if offset > buffer_size {
         return Err(TransferError::BufferStartOffsetOverrun {
             start_offset: offset,
             buffer_size: bytes_in_copy,
@@ -1000,7 +1000,7 @@ pub(super) fn copy_buffer_to_buffer(
     let dst_barrier = dst_pending.map(|pending| pending.into_hal(dst_buffer, state.snatch_guard));
 
     // TODO: This check isn't part of the spec., but it looks like it should be.
-    if source_offset >= src_buffer.size {
+    if source_offset > src_buffer.size {
         return Err(TransferError::BufferStartOffsetOverrun {
             start_offset: destination_offset,
             buffer_size: dst_buffer.size,