linux-kernel - [PATCH] ksmbd: Use scope-based resource management in ksmbd_validate_name

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Message-ID: <1abbfe84-e3f1-4163-9789-6ec49a3ce821@web.de>
Date: Sat, 4 Oct 2025 13:36:54 +0200
From: Markus Elfring <Markus.Elfring@....de>
To: linux-cifs@...r.kernel.org, Namjae Jeon <linkinjeon@...nel.org>,
 Sergey Senozhatsky <senozhatsky@...omium.org>,
 Steve French <smfrench@...il.com>, Tom Talpey <tom@...pey.com>
Cc: LKML <linux-kernel@...r.kernel.org>, kernel-janitors@...r.kernel.org,
 Neil Brown <neil@...wn.name>, Stefan Metzmacher <metze@...ba.org>
Subject: [PATCH] ksmbd: Use scope-based resource management in
 ksmbd_validate_name_reconnect()

From: Markus Elfring <elfring@...rs.sourceforge.net>
Date: Sat, 4 Oct 2025 13:27:12 +0200

Scope-based resource management became supported for some
programming interfaces by contributions of Peter Zijlstra on 2023-05-26.
See also the commit 54da6a0924311c7cf5015533991e44fb8eb12773 ("locking:
Introduce __cleanup() based infrastructure").

* Thus use the attribute “__free(kfree)”.

* Reduce the scope for the local variable “ab_pathname”.

* Omit two kfree() calls accordingly.

* Return status codes directly without using an intermediate variable.

Signed-off-by: Markus Elfring <elfring@...rs.sourceforge.net>
---
 fs/smb/server/vfs_cache.c | 17 ++++++-----------
 1 file changed, 6 insertions(+), 11 deletions(-)

diff --git a/fs/smb/server/vfs_cache.c b/fs/smb/server/vfs_cache.c
index dfed6fce8904..af8a16879b88 100644
--- a/fs/smb/server/vfs_cache.c
+++ b/fs/smb/server/vfs_cache.c
@@ -933,27 +933,22 @@ void ksmbd_free_global_file_table(void)
 int ksmbd_validate_name_reconnect(struct ksmbd_share_config *share,
 				  struct ksmbd_file *fp, char *name)
 {
-	char *pathname, *ab_pathname;
-	int ret = 0;
+	char *pathname __free(kfree) = kmalloc(PATH_MAX, KSMBD_DEFAULT_GFP);
 
-	pathname = kmalloc(PATH_MAX, KSMBD_DEFAULT_GFP);
 	if (!pathname)
 		return -EACCES;
 
-	ab_pathname = d_path(&fp->filp->f_path, pathname, PATH_MAX);
-	if (IS_ERR(ab_pathname)) {
-		kfree(pathname);
+	char *ab_pathname = d_path(&fp->filp->f_path, pathname, PATH_MAX);
+
+	if (IS_ERR(ab_pathname))
 		return -EACCES;
-	}
 
 	if (name && strcmp(&ab_pathname[share->path_sz + 1], name)) {
 		ksmbd_debug(SMB, "invalid name reconnect %s\n", name);
-		ret = -EINVAL;
+		return -EINVAL;
 	}
 
-	kfree(pathname);
-
-	return ret;
+	return 0;
 }
 
 int ksmbd_reopen_durable_fd(struct ksmbd_work *work, struct ksmbd_file *fp)
-- 
2.51.0