ksmbd: fix unexpectedly changed path in ksmbd_vfs_kern_path_locked

[ Upstream commit 2ac538e40278a2c0c051cca81bcaafc547d61372 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/fs/smb/server/vfs.c b/fs/smb/server/vfs.c
index eaae67a2f720eeb799b9803a15907435904cad82..396d4ea77d34ac7e120865ff8520615dcb76381d 100644 (file)
--- a/fs/smb/server/vfs.c
+++ b/fs/smb/server/vfs.c
@@ -1249,6 +1249,8 @@ 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)
@@ -1256,7 +1258,6 @@ 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;
                }