linux-kernel - RE: [[PATCH v1] 14/37] [CIFS] SMBD: Post a SMBD data transfer message with page payload

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 14 Aug 2017 20:23:13 +0000
From:   Tom Talpey <ttalpey@...rosoft.com>
To:     Long Li <longli@...rosoft.com>, Steve French <sfrench@...ba.org>,
        "linux-cifs@...r.kernel.org" <linux-cifs@...r.kernel.org>,
        "samba-technical@...ts.samba.org" <samba-technical@...ts.samba.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: RE: [[PATCH v1] 14/37] [CIFS] SMBD: Post a SMBD data transfer message
 with page payload

> -----Original Message-----
> From: linux-cifs-owner@...r.kernel.org [mailto:linux-cifs-
> owner@...r.kernel.org] On Behalf Of Long Li
> Sent: Wednesday, August 2, 2017 4:10 PM
> To: Steve French <sfrench@...ba.org>; linux-cifs@...r.kernel.org; samba-
> technical@...ts.samba.org; linux-kernel@...r.kernel.org
> Cc: Long Li <longli@...rosoft.com>
> Subject: [[PATCH v1] 14/37] [CIFS] SMBD: Post a SMBD data transfer message
> with page payload
> 
>  /*
> + * Send a page
> + * page: the page to send
> + * offset: offset in the page to send
> + * size: length in the page to send
> + * remaining_data_length: remaining data to send in this payload
> + */
> +static int cifs_rdma_post_send_page(struct cifs_rdma_info *info, struct page
> *page,
> +               unsigned long offset, size_t size, int remaining_data_length)
> +{
>...
> +       wait_event(info->wait_send_queue, atomic_read(&info->send_credits) >
> 0);

This is an uninterruptible wait, correct? What's to guarantee the event will
ever fire? Also, if the count is zero, there should be a check that an SMB Direct
credit request is outstanding. If not, it's wasteful to sleep for the keepalive timer
to do so.

Tom.