netdev - Re: BUG_ON in skb_segment, after bpf_skb_change

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]

Message-ID: <20190828085608.12053dac@pixies>
Date:   Wed, 28 Aug 2019 08:56:08 +0300
From:   Shmulik Ladkani <shmulik.ladkani@...il.com>
To:     Daniel Borkmann <daniel@...earbox.net>
Cc:     Eric Dumazet <eric.dumazet@...il.com>,
        netdev <netdev@...r.kernel.org>,
        Alexander Duyck <alexander.duyck@...il.com>,
        Alexei Starovoitov <ast@...nel.org>,
        Yonghong Song <yhs@...com>,
        Steffen Klassert <steffen.klassert@...unet.com>,
        shmulik@...anetworks.com, eyal@...anetworks.com
Subject: Re: BUG_ON in skb_segment, after bpf_skb_change_proto was applied

On Tue, 27 Aug 2019 14:10:35 +0200
Daniel Borkmann <daniel@...earbox.net> wrote:

> Given first point above wrt hitting rarely, it would be good to first get a
> better understanding for writing a reproducer. Back then Yonghong added one
> to the BPF kernel test suite [0], so it would be desirable to extend it for
> the case you're hitting. Given NAT64 use-case is needed and used by multiple
> parties, we should try to (fully) fix it generically.

Thanks Daniel for the advice.

I'm working on a reproducer that resembles the input skb which triggers
this BUG_ON.