diff --git a/fs/ntfs/bdev-io.c b/fs/ntfs/bdev-io.c
index 67e65c88d681..27d7c2767a33 100644
--- a/fs/ntfs/bdev-io.c
+++ b/fs/ntfs/bdev-io.c
@@ -97,6 +97,8 @@ int ntfs_bdev_write(struct super_block *sb, void *buf, loff_t start, size_t size
 		idx_end++;
 
 	for (; idx < idx_end; idx++, from = 0) {
+		u32 len;
+
 		folio = read_mapping_folio(sb->s_bdev->bd_mapping, idx, NULL);
 		if (IS_ERR(folio)) {
 			ntfs_error(sb, "Unable to read %ld page", idx);
@@ -105,9 +107,10 @@ int ntfs_bdev_write(struct super_block *sb, void *buf, loff_t start, size_t size
 
 		offset = (loff_t)idx << PAGE_SHIFT;
 		to = min_t(u32, end - offset, PAGE_SIZE);
+		len = to - from;
 
-		memcpy_to_folio(folio, from, buf + buf_off, to);
-		buf_off += to;
+		memcpy_to_folio(folio, from, buf + buf_off, len);
+		buf_off += len;
 		folio_mark_uptodate(folio);
 		folio_mark_dirty(folio);
 		folio_put(folio);