linux-kernel - Re: [PATCH v1] gve: fix zero size queue page list allocation

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]

Message-ID: <20220214212136.71e5b4c6@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com>
Date:   Mon, 14 Feb 2022 21:21:36 -0800
From:   Jakub Kicinski <kuba@...nel.org>
To:     Haiyue Wang <haiyue.wang@...el.com>
Cc:     netdev@...r.kernel.org, Jeroen de Borst <jeroendb@...gle.com>,
        Catherine Sullivan <csully@...gle.com>,
        David Awogbemila <awogbemila@...gle.com>,
        "David S. Miller" <davem@...emloft.net>,
        Willem de Bruijn <willemb@...gle.com>,
        Bailey Forrest <bcf@...gle.com>, Tao Liu <xliutaox@...gle.com>,
        Christophe JAILLET <christophe.jaillet@...adoo.fr>,
        John Fraker <jfraker@...gle.com>,
        Yangchun Fu <yangchun@...gle.com>,
        linux-kernel@...r.kernel.org (open list)
Subject: Re: [PATCH v1] gve: fix zero size queue page list allocation

On Mon, 14 Feb 2022 10:41:29 +0800 Haiyue Wang wrote:
> According to the two functions 'gve_num_tx/rx_qpls', only the queue with
> GVE_GQI_QPL_FORMAT format has queue page list.
> 
> The 'queue_format == GVE_GQI_RDA_FORMAT' may lead to request zero sized
> memory allocation, like if the queue format is GVE_DQO_RDA_FORMAT.
> 
> The kernel memory subsystem will return ZERO_SIZE_PTR, which is not NULL
> address, so the driver can run successfully. Also the code still checks
> the queue page list number firstly, then accesses the allocated memory,
> so zero number queue page list allocation will not lead to access fault.
> 
> Use the queue page list number to detect no QPLs, it can avoid zero size
> queue page list memory allocation.

There's no bug here, strictly speaking, the driver will function
correctly? In that case please repost without the Fixes tag and
with [PATCH net-next] in the subject.

> Fixes: a5886ef4f4bf ("gve: Introduce per netdev `enum gve_queue_format`")
> Signed-off-by: Haiyue Wang <haiyue.wang@...el.com>