This is a note to let you know that I've just added the patch titled ksmbd: fix slab-out-of-bounds in smb_strndup_from_utf16() to the 6.6-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: ksmbd-fix-slab-out-of-bounds-in-smb_strndup_from_utf.patch and it can be found in the queue-6.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 1d1854317e5b7cf9f6498d4a7dfcb3141e0c74a5 Author: Namjae Jeon <linkinjeon@xxxxxxxxxx> Date: Sat Mar 16 23:36:36 2024 +0900 ksmbd: fix slab-out-of-bounds in smb_strndup_from_utf16() [ Upstream commit d10c77873ba1e9e6b91905018e29e196fd5f863d ] If ->NameOffset/Length is bigger than ->CreateContextsOffset/Length, ksmbd_check_message doesn't validate request buffer it correctly. So slab-out-of-bounds warning from calling smb_strndup_from_utf16() in smb2_open() could happen. If ->NameLength is non-zero, Set the larger of the two sums (Name and CreateContext size) as the offset and length of the data area. Reported-by: Yang Chaoming <lometsj@xxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Namjae Jeon <linkinjeon@xxxxxxxxxx> Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/fs/smb/server/smb2misc.c b/fs/smb/server/smb2misc.c index 03dded29a9804..7c872ffb4b0a9 100644 --- a/fs/smb/server/smb2misc.c +++ b/fs/smb/server/smb2misc.c @@ -107,7 +107,10 @@ static int smb2_get_data_area_len(unsigned int *off, unsigned int *len, case SMB2_CREATE: { unsigned short int name_off = - le16_to_cpu(((struct smb2_create_req *)hdr)->NameOffset); + max_t(unsigned short int, + le16_to_cpu(((struct smb2_create_req *)hdr)->NameOffset), + offsetof(struct smb2_create_req, Buffer)); + unsigned short int name_len = le16_to_cpu(((struct smb2_create_req *)hdr)->NameLength);