From: He Wang <xw897002528@gmail.com>
Date: Mon, 6 Jan 2025 03:39:54 +0000 (+0000)
Subject: ksmbd: fix unexpectedly changed path in ksmbd_vfs_kern_path_locked
X-Git-Tag: v6.13-rc7~28^2~1
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=2ac538e40278a2c0c051cca81bcaafc547d61372;p=thirdparty%2Flinux.git

ksmbd: fix unexpectedly changed path in ksmbd_vfs_kern_path_locked

When `ksmbd_vfs_kern_path_locked` met an error and it is not the last
entry, it will exit without restoring changed path buffer. But later this
buffer may be used as the filename for creation.

Fixes: c5a709f08d40 ("ksmbd: handle caseless file creation")
Signed-off-by: He Wang <xw897002528@gmail.com>
Acked-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
---

diff --git a/fs/smb/server/vfs.c b/fs/smb/server/vfs.c
index 88d167a5f8b7b..40f08eac519c7 100644
--- a/fs/smb/server/vfs.c
+++ b/fs/smb/server/vfs.c
@@ -1264,6 +1264,8 @@ int ksmbd_vfs_kern_path_locked(struct ksmbd_work *work, char *name,
 					      filepath,
 					      flags,
 					      path);
+			if (!is_last)
+				next[0] = '/';
 			if (err)
 				goto out2;
 			else if (is_last)
@@ -1271,7 +1273,6 @@ int ksmbd_vfs_kern_path_locked(struct ksmbd_work *work, char *name,
 			path_put(parent_path);
 			*parent_path = *path;
 
-			next[0] = '/';
 			remain_len -= filename_len + 1;
 		}