ext4: Use generic_ci_validate_strict_name helper

Use the helper function to check the requirements for casefold
directories using strict encoding.

Suggested-by: Gabriel Krisman Bertazi <[email protected]>
Signed-off-by: André Almeida <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Acked-by: Theodore Ts'o <[email protected]>
Reviewed-by: Gabriel Krisman Bertazi <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>

Author: andrealmeid

fs/ext4/namei.c

@@ -2395,11 +2395,8 @@ static int ext4_add_entry(handle_t *handle, struct dentry *dentry,
 	if (fscrypt_is_nokey_name(dentry))
 		return -ENOKEY;
 
-#if IS_ENABLED(CONFIG_UNICODE)
-	if (sb_has_strict_encoding(sb) && IS_CASEFOLDED(dir) &&
-	    utf8_validate(sb->s_encoding, &dentry->d_name))
+	if (!generic_ci_validate_strict_name(dir, &dentry->d_name))
 		return -EINVAL;
-#endif
 
 	retval = ext4_fname_setup_filename(dir, &dentry->d_name, 0, &fname);
 	if (retval)