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  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:   Sat, 08 Jan 2022 21:21:04 +0100
From:   Toke Høiland-Jørgensen <>
To:     Alexei Starovoitov <>
Cc:     Alexei Starovoitov <>,
        Daniel Borkmann <>,
        "David S. Miller" <>,
        Jakub Kicinski <>,
        Jesper Dangaard Brouer <>,
        John Fastabend <>,
        Andrii Nakryiko <>,
        Martin KaFai Lau <>,
        Song Liu <>, Yonghong Song <>,
        KP Singh <>,
        syzbot <>,
        Network Development <>,
        bpf <>
Subject: Re: [PATCH bpf v2 1/3] xdp: check prog type before updating BPF link

Alexei Starovoitov <> writes:

> On Fri, Jan 7, 2022 at 2:11 PM Toke Høiland-Jørgensen <> wrote:
>> The bpf_xdp_link_update() function didn't check the program type before
>> updating the program, which made it possible to install any program type as
>> an XDP program, which is obviously not good. Syzbot managed to trigger this
>> by swapping in an LWT program on the XDP hook which would crash in a helper
>> call.
>> Fix this by adding a check and bailing out if the types don't match.
>> Fixes: 026a4c28e1db ("bpf, xdp: Implement LINK_UPDATE for BPF XDP link")
>> Reported-by:
>> Acked-by: Andrii Nakryiko <>
>> Signed-off-by: Toke Høiland-Jørgensen <>
> Thanks a lot for the quick fix!
> The merge window is about to begin.
> We will land it as soon as possible when bpf tree will be ready
> to accept fixes.

You're welcome! That's fine; FWIW, I believe the patch applies cleanly
to bpf-next as well, if that makes things easier on your end :)


Powered by blists - more mailing lists