From 1b0ac3478fceafe46fe376da437a2813bc881e20 Mon Sep 17 00:00:00 2001 From: He Wang Date: Mon, 6 Jan 2025 03:39:54 +0000 Subject: [PATCH] ksmbd: fix unexpectedly changed path in ksmbd_vfs_kern_path_locked BugLink: https://bugs.launchpad.net/bugs/2106770 [ 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 Acked-by: Namjae Jeon Signed-off-by: Steve French Signed-off-by: Sasha Levin CVE-2025-21660 Signed-off-by: Manuel Diewald Signed-off-by: Mehmet Basaran --- fs/smb/server/vfs.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/smb/server/vfs.c b/fs/smb/server/vfs.c index 9660b734ddea..333b25fec4ba 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; }