Looks good. I tested it and it works.
With this I can see some additional things work e.g. "stat /mnt/file"
shows the correct mode bits, but the owner and group are reported as
the default (0) instead of the actual uid/gid
On Fri, Jan 21, 2022 at 7:47 PM Namjae Jeon <linkinjeon@xxxxxxxxxx> wrote:
>
> cifs client set 4 to DataLength of create_posix context, which mean
> Mode variable of create_posix context is only available. So buffer
> validation of ksmbd should check only the size of Mode except for
> the size of Reserved variable.
>
> Fixes: 8f77150c15f8 ("ksmbd: add buffer validation for SMB2_CREATE_CONTEXT")
> Cc: stable@xxxxxxxxxxxxxxx # v5.15+
> Reported-by: Steve French <smfrench@xxxxxxxxx>
> Signed-off-by: Namjae Jeon <linkinjeon@xxxxxxxxxx>
> ---
> fs/ksmbd/smb2pdu.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
> index 1866c81c5c99..3926ca18dca4 100644
> --- a/fs/ksmbd/smb2pdu.c
> +++ b/fs/ksmbd/smb2pdu.c
> @@ -2688,7 +2688,7 @@ int smb2_open(struct ksmbd_work *work)
> (struct create_posix *)context;
> if (le16_to_cpu(context->DataOffset) +
> le32_to_cpu(context->DataLength) <
> - sizeof(struct create_posix)) {
> + sizeof(struct create_posix) - 4) {
> rc = -EINVAL;
> goto err_out1;
> }
> --
> 2.25.1
>
--
Thanks,
Steve
