Re: [PATCH 1/3] smb/server: fix signing when a response uses more than one iov
Andy Shevchenko <[email protected]>
| Newsgroups | org.kernel.vger.linux-cifs |
|---|---|
| Organization | Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs, Bertel Jungin Aukio 5, 02600 Espoo |
| Message-ID | <[email protected]> |
On Wed, Jul 15, 2026 at 01:55:11PM +0000, ChenXiaoSong wrote:
> Some SMB responses keep their data in another buffer. The SMB header
> and the data are then in different iovs.
>
> The old code only handled this for SMB2 READ. For other commands, it
> signed only the last iov. QUERY_INFO and CHANGE_NOTIFY can also use
> another iov for their data. Their SMB header was not signed, so Windows
> will client rejected the response.
>
> Find the iov that starts with the current SMB header. Sign this iov and
> all iovs after it.
...
> +static struct kvec *smb2_get_sign_rsp_iov(struct ksmbd_work *work,
> + struct smb2_hdr *hdr, int *n_vec)
> +{
> + int i;
> +
> + /*
> + * iov[0] has the RFC1002 message length. It is not part of the SMB2
> + * message, so do not sign it.
> + */
> + for (i = 1; i <= work->iov_idx; i++) {
for (int i = 1; i <= work->iov_idx; i++) {
(or even unsigned int). This style is preferred as long as iterator is local
to the loop.
> + if (work->iov[i].iov_base == hdr) {
> + *n_vec = work->iov_idx - i + 1;
> + return &work->iov[i];
> + }
> + }
> +
> + WARN_ON_ONCE(work->iov_idx < 1 ||
> + work->iov[work->iov_idx].iov_base != hdr);
> + *n_vec = 1;
> + return &work->iov[work->iov_idx];
> +}
--
With Best Regards,
Andy Shevchenko