Re: [PATCH 3/3] smb: client: use unaligned read for POSIX info name length

owner sid sizes are variable but they look like always a multiple of 4
so should be aligned already, right?

See posix_info_sid_size() function

On Wed, Jul 1, 2026 at 5:26 AM Ren Wei <[email protected]> wrote:
>
> From: Zihan Xi <[email protected]>
>
> posix_info_parse() reads the trailing name length via an aligned le32
> cast at beg + total_len. Owner and group SID sizes are variable, so
> that offset may be misaligned on strict-alignment architectures.
>
> Fixes: 349e13ad30b4 ("cifs: add smb2 POSIX info level")
> Cc: [email protected]
> Signed-off-by: Zihan Xi <[email protected]>
> Signed-off-by: Ren Wei <[email protected]>
> ---
>  fs/smb/client/smb2pdu.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/smb/client/smb2pdu.c b/fs/smb/client/smb2pdu.c
> index ed782d219d55..43d514ee555d 100644
> --- a/fs/smb/client/smb2pdu.c
> +++ b/fs/smb/client/smb2pdu.c
> @@ -5450,7 +5450,7 @@ int posix_info_parse(const void *beg, const void *end,
>         /* check name len */
>         if (beg + total_len + 4 > end)
>                 return -1;
> -       name_len = le32_to_cpu(*(__le32 *)(beg + total_len));
> +       name_len = get_unaligned_le32((u8 *)beg + total_len);
>         if (name_len < 1 || name_len > 0xFFFF)
>                 return -1;
>         total_len += 4;
> --
> 2.43.0
>
>


-- 
Thanks,

Steve