netdev - Re: [PATCH net] Drop packets with invalid headers to prevent KMSAN infoleak

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: <c0e98969-a75e-45a0-803c-1d69bf02623b@linux.dev>
Date: Sun, 27 Oct 2024 22:42:08 -0700
From: Yonghong Song <yonghong.song@...ux.dev>
To: Daniel Yang <danielyangkang@...il.com>,
 Martin KaFai Lau <martin.lau@...ux.dev>
Cc: Daniel Borkmann <daniel@...earbox.net>,
 John Fastabend <john.fastabend@...il.com>,
 Alexei Starovoitov <ast@...nel.org>, Andrii Nakryiko <andrii@...nel.org>,
 Eduard Zingerman <eddyz87@...il.com>, Song Liu <song@...nel.org>,
 KP Singh <kpsingh@...nel.org>, Stanislav Fomichev <sdf@...ichev.me>,
 Hao Luo <haoluo@...gle.com>, Jiri Olsa <jolsa@...nel.org>,
 "David S. Miller" <davem@...emloft.net>, Eric Dumazet <edumazet@...gle.com>,
 Jakub Kicinski <kuba@...nel.org>, Paolo Abeni <pabeni@...hat.com>,
 "open list:BPF [NETWORKING] (tcx & tc BPF, sock_addr)"
 <bpf@...r.kernel.org>,
 "open list:BPF [NETWORKING] (tcx & tc BPF, sock_addr)"
 <netdev@...r.kernel.org>, open list <linux-kernel@...r.kernel.org>,
 syzbot+346474e3bf0b26bd3090@...kaller.appspotmail.com
Subject: Re: [PATCH net] Drop packets with invalid headers to prevent KMSAN
 infoleak

On 10/27/24 1:49 AM, Daniel Yang wrote:
> On Tue, Oct 22, 2024 at 11:14 AM Martin KaFai Lau <martin.lau@...ux.dev> wrote:
>> On 10/21/24 6:37 PM, Daniel Yang wrote:
>>>> A test in selftests/bpf is needed to reproduce and better understand this.
>>> I don't know much about self tests but I've just been using the syzbot
>>> repro and #syz test at the link in the patch:
>>> https://syzkaller.appspot.com/bug?extid=346474e3bf0b26bd3090. Testing
>>> the patch showed that the uninitialized memory was not getting written
>>> to memory.
>>>
>>>> Only bpf_clone_redirect() is needed to reproduce or other bpf_skb_*() helpers calls
>>>> are needed to reproduce?
>> If only bpf_clone_redirect() is needed, it should be simple to write a selftest
>> to reproduce it. It also helps to catch future regression.
>>
>> Please tag the next respin as "bpf" also.
> I have a problem. I can't seem to build the bpf kselftests for some
> reason. There is always a struct definition error:
> In file included from progs/profiler1.c:5:
> progs/profiler.inc.h:599:49: error: declaration of 'struct
> syscall_trace_enter' will not be visible outside of t]
>    599 | int tracepoint__syscalls__sys_enter_kill(struct
> syscall_trace_enter* ctx)
>        |                                                 ^
> progs/profiler.inc.h:604:15: error: incomplete definition of type
> 'struct syscall_trace_enter'
>    604 |         int pid = ctx->args[0];
>        |                   ~~~^
> progs/profiler.inc.h:599:49: note: forward declaration of 'struct
> syscall_trace_enter'
>    599 | int tracepoint__syscalls__sys_enter_kill(struct
> syscall_trace_enter* ctx)
>        |                                                 ^
> progs/profiler.inc.h:605:15: error: incomplete definition of type
> 'struct syscall_trace_enter'
>    605 |         int sig = ctx->args[1];
>        |                   ~~~^
> progs/profiler.inc.h:599:49: note: forward declaration of 'struct
> syscall_trace_enter'
>    599 | int tracepoint__syscalls__sys_enter_kill(struct
> syscall_trace_enter* ctx)
>
> I just run the following to build:
> $ cd tools/testing/selftests/bpf/
> $ make

It might be due to your .config file.
The 'struct syscall_trace_enter' is defined in kernel/trace/trace.h,
which is used in kernel/trace/trace_syscalls.c. Maybe your config
does not have CONFIG_FTRACE_SYSCALLS?

>
> I can't find anyone else encountering the same error.