exfat: Fix bitwise operation having different size

cpos has type loff_t (long long), while s_blocksize has type u32. The
inversion wil happen on u32, the coercion to s64 happens afterwards and
will do 0-left-paddding, resulting in the upper bits getting masked out.

Cast s_blocksize to loff_t before negating it.

Found by static code analysis using Klocwork.

Signed-off-by: Philipp Hahn <phahn-oss@avm.de>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>

Author: pmhahn

fs/exfat/dir.c

@@ -249,7 +249,7 @@ static int exfat_iterate(struct file *file, struct dir_context *ctx)
 		 */
 		if (err == -EIO) {
 			cpos += 1 << (sb->s_blocksize_bits);
-			cpos &= ~(sb->s_blocksize - 1);
+			cpos &= ~(loff_t)(sb->s_blocksize - 1);
 		}
 
 		err = -EIO;