linux-kernel - Re: [PATCH net] cls_matchall: avoid panic when receiving a packet before filter set

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: Windows password security audit tool. GUI, reports in PDF.

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

Date:   Thu, 2 May 2019 09:31:21 -0700
From:   Cong Wang <xiyou.wangcong@...il.com>
To:     Matteo Croce <mcroce@...hat.com>
Cc:     Linux Kernel Network Developers <netdev@...r.kernel.org>,
        LKML <linux-kernel@...r.kernel.org>,
        Jamal Hadi Salim <jhs@...atatu.com>,
        Jiri Pirko <jiri@...nulli.us>,
        "David S. Miller" <davem@...emloft.net>,
        Vlad Buslov <vladbu@...lanox.com>
Subject: Re: [PATCH net] cls_matchall: avoid panic when receiving a packet
 before filter set

On Thu, May 2, 2019 at 1:51 AM Matteo Croce <mcroce@...hat.com> wrote:
>
> When a matchall classifier is added, there is a small time interval in
> which tp->root is NULL. If we receive a packet in this small time slice
> a NULL pointer dereference will happen, leading to a kernel panic:
...
> Fix this by adding a NULL check in mall_classify().
>
> Fixes: ed76f5edccc9 ("net: sched: protect filter_chain list with filter_chain_lock mutex")
> Signed-off-by: Matteo Croce <mcroce@...hat.com>

Acked-by: Cong Wang <xiyou.wangcong@...il.com>


Thanks for the update!