netdev - Re: [Patch net] ax25: fix a use-after-free in ax25_fillin

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:   Sun, 30 Dec 2018 14:08:23 -0800 (PST)
From:   David Miller <davem@...emloft.net>
To:     xiyou.wangcong@...il.com
Cc:     netdev@...r.kernel.org
Subject: Re: [Patch net] ax25: fix a use-after-free in ax25_fillin_cb()

From: Cong Wang <xiyou.wangcong@...il.com>
Date: Sat, 29 Dec 2018 13:56:36 -0800

> There are multiple issues here:
> 
> 1. After freeing dev->ax25_ptr, we need to set it to NULL otherwise
>    we may use a dangling pointer.
> 
> 2. There is a race between ax25_setsockopt() and device notifier as
>    reported by syzbot. Close it by holding RTNL lock.
> 
> 3. We need to test if dev->ax25_ptr is NULL before using it.
> 
> Reported-and-tested-by: syzbot+ae6bb869cbed29b29040@...kaller.appspotmail.com
> Signed-off-by: Cong Wang <xiyou.wangcong@...il.com>

Applied and queued up for -stable, thanks Cong.