public inbox for linux-security-module@vger.kernel.org
 help / color / mirror / Atom feed
From: Justin Suess <utilityemal77@gmail.com>
To: 王志 <23009200614@stu.xidian.edu.cn>
Cc: linux-security-module@vger.kernel.org,
	linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
	paul@paul-moore.com
Subject: Re: [BUG] landlock: warning in collect_domain_accesses via renameat2 path rename
Date: Sat, 18 Apr 2026 19:08:34 -0400	[thread overview]
Message-ID: <aeQO8plVsM4dg9jL@suesslenovo> (raw)
In-Reply-To: <25536ce2.4391.19d9b3484ff.Coremail.23009200614@stu.xidian.edu.cn>

On Fri, Apr 17, 2026 at 07:30:03PM +0800, 王志 wrote:
> Dear Maintainers,
> 
> When using our customized Syzkaller to fuzz the latest Linux kernel, we discovered a crash related to Landlock during a path rename operation.
> 
> HEAD commit: 7d0a66e4bb9081d75c82ec4957c50034cb0ea449

This is the initial 6.18 release, without the stable backported fixes.

> git tree: upstream
> 
> Reproducer and logs:
> Output: https://github.com/manual0/crash/blob/main/cebd27007e806e16cf15cb1e0214c24054e8998e/report1
> Kernel config: https://github.com/manual0/crash/blob/main/6.18-syzbot.config
> C reproducer: https://github.com/manual0/crash/blob/main/cebd27007e806e16cf15cb1e0214c24054e8998e/repro.c
> 
> ----------------------------------------
> 
> Analysis:
> 
> The crash is triggered through the following path:
> 
> renameat2
>   → security_path_rename
>   → current_check_refer_path
>   → collect_domain_accesses
> 
> This indicates that a path rename operation triggers Landlock's path access control checks. The crash occurs inside collect_domain_accesses(), which is responsible for collecting the current process's domain access rights.
> 
> The bug is caused by collect_domain_accesses() traversing inconsistent or invalid Landlock ruleset data during rename path permission checks, leading to unsafe memory access.
> ----------------------------------------
> 
> If you fix this issue, please add the following tag to the commit:
> 
> Reported-by: Zhi Wang <wangzhi@stu.xidian.edu.cn>
>
This was fixed in 6.18.2 with
cadb28f8b3fd6908e3051e86158c65c3a8e1c907 (landlock: Fix handling of
disconnected directories) [1]

So this has been fixed upstream and backported already.

Please target fuzzing against a supported tag.

[1]: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=linux-6.18.y&id=cadb28f8b3fd6908e3051e86158c65c3a8e1c907

Justin
> Thanks,
> Zhi Wang

      reply	other threads:[~2026-04-18 23:08 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-04-17 11:30 [BUG] landlock: warning in collect_domain_accesses via renameat2 path rename 王志
2026-04-18 23:08 ` Justin Suess [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=aeQO8plVsM4dg9jL@suesslenovo \
    --to=utilityemal77@gmail.com \
    --cc=23009200614@stu.xidian.edu.cn \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-security-module@vger.kernel.org \
    --cc=paul@paul-moore.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox