linux-kernel - Re: [PATCH v3 0/2] bpf: Fix verifier crash on BPF

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: <15515a5f10587827b33b3e9eaeb854d5c96e88c6.camel@gmail.com>
Date: Wed, 01 Oct 2025 11:40:35 -0700
From: Eduard Zingerman <eddyz87@...il.com>
To: Brahmajit Das <listout@...tout.xyz>, 
	syzbot+d36d5ae81e1b0a53ef58@...kaller.appspotmail.com
Cc: andrii@...nel.org, ast@...nel.org, bpf@...r.kernel.org,
 daniel@...earbox.net, 	haoluo@...gle.com, john.fastabend@...il.com,
 jolsa@...nel.org, kpsingh@...nel.org, 	linux-kernel@...r.kernel.org,
 martin.lau@...ux.dev, sdf@...ichev.me, 	song@...nel.org,
 syzkaller-bugs@...glegroups.com, yonghong.song@...ux.dev, 
	kafai.wan@...ux.dev
Subject: Re: [PATCH v3 0/2] bpf: Fix verifier crash on BPF_NEG with pointer
 register

On Wed, 2025-10-01 at 15:26 +0530, Brahmajit Das wrote:
> This patch fixes a crash in the BPF verifier triggered when the BPF_NEG
> operation is applied to a pointer-typed register. The verifier now
> checks that the destination register is not a pointer before performing
> the operation.
> 
> Tested with syzkaller reproducer and new BPF sefltest.
> Closes: https://syzkaller.appspot.com/bug?extid=d36d5ae81e1b0a53ef58

Nit: In the future, could you please include links to previous
     patch-set versions in the cover letter?  These links are usually
     accompanied with a short description of changes from version to
     version.

> 
> Brahmajit Das (1):
>   bpf: Skip scalar adjustment for BPF_NEG if dst is a pointer
> 
> KaFai Wan (1):
>   selftests/bpf: Add test for BPF_NEG alu on CONST_PTR_TO_MAP
> 
>  kernel/bpf/verifier.c                          |  3 ++-
>  .../bpf/progs/verifier_value_illegal_alu.c     | 18 ++++++++++++++++++
>  2 files changed, 20 insertions(+), 1 deletion(-)