linux-fsdevel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@infradead.org>
To: Song Liu <songliubraving@meta.com>
Cc: Christoph Hellwig <hch@infradead.org>, Song Liu <song@kernel.org>,
	bpf <bpf@vger.kernel.org>,
	Linux-Fsdevel <linux-fsdevel@vger.kernel.org>,
	LKML <linux-kernel@vger.kernel.org>,
	Kernel Team <kernel-team@meta.com>,
	Andrii Nakryiko <andrii@kernel.org>,
	Eduard Zingerman <eddyz87@gmail.com>,
	Alexei Starovoitov <ast@kernel.org>,
	Daniel Borkmann <daniel@iogearbox.net>,
	Martin KaFai Lau <martin.lau@linux.dev>,
	Al Viro <viro@zeniv.linux.org.uk>,
	Christian Brauner <brauner@kernel.org>, Jan Kara <jack@suse.cz>,
	KP Singh <kpsingh@kernel.org>,
	Matt Bobrowski <mattbobrowski@google.com>
Subject: Re: [PATCH bpf-next 2/2] selftests/bpf: Extend test fs_kfuncs to cover security.bpf xattr names
Date: Mon, 14 Oct 2024 22:25:53 -0700	[thread overview]
Message-ID: <Zw384bed3yVgZpoc@infradead.org> (raw)
In-Reply-To: <0DB83868-0049-40E3-8E62-0D8D913CB9CB@fb.com>

On Tue, Oct 15, 2024 at 05:21:48AM +0000, Song Liu wrote:
> >> Extend test_progs fs_kfuncs to cover different xattr names. Specifically:
> >> xattr name "user.kfuncs", "security.bpf", and "security.bpf.xxx" can be
> >> read from BPF program with kfuncs bpf_get_[file|dentry]_xattr(); while
> >> "security.bpfxxx" and "security.selinux" cannot be read.
> > 
> > So you read code from untrusted user.* xattrs?  How can you carve out
> > that space and not known any pre-existing userspace cod uses kfuncs
> > for it's own purpose?
> 
> I don't quite follow the comment here. 
> 
> Do you mean user.* xattrs are untrusted (any user can set it), so we 
> should not allow BPF programs to read them? Or do you mean xattr 
> name "user.kfuncs" might be taken by some use space?

All of the above.


  reply	other threads:[~2024-10-15  5:25 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-10-02 21:46 [PATCH bpf-next 0/2] security.bpf xattr name prefix Song Liu
2024-10-02 21:46 ` [PATCH bpf-next 1/2] fs/xattr: bpf: Introduce " Song Liu
2024-10-07  8:39   ` Jiri Olsa
2024-10-07 17:15     ` Song Liu
2024-10-14 10:18   ` Christian Brauner
2024-10-02 21:46 ` [PATCH bpf-next 2/2] selftests/bpf: Extend test fs_kfuncs to cover security.bpf xattr names Song Liu
2024-10-15  5:07   ` Christoph Hellwig
2024-10-15  5:21     ` Song Liu
2024-10-15  5:25       ` Christoph Hellwig [this message]
2024-10-15  5:52         ` Song Liu
2024-10-15  6:42           ` Christoph Hellwig
2024-10-15 13:54             ` Song Liu
2024-10-16  7:49               ` Christoph Hellwig
2024-10-16 13:51           ` Jan Kara
2024-10-16 14:51             ` Christian Brauner
2024-10-16 16:38               ` Song Liu
2024-10-17 15:03               ` Christoph Hellwig
2024-10-21 13:24                 ` Christian Brauner
2024-10-23  6:45                   ` Christoph Hellwig
2024-10-30 20:44                     ` Song Liu
2024-10-31  6:56                       ` Christoph Hellwig
2024-10-31 15:56                         ` Song Liu
2024-10-31 16:10                           ` Alexei Starovoitov
2024-10-11 17:40 ` [PATCH bpf-next 0/2] security.bpf xattr name prefix Song Liu
2024-10-14 10:18   ` Christian Brauner

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=Zw384bed3yVgZpoc@infradead.org \
    --to=hch@infradead.org \
    --cc=andrii@kernel.org \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=brauner@kernel.org \
    --cc=daniel@iogearbox.net \
    --cc=eddyz87@gmail.com \
    --cc=jack@suse.cz \
    --cc=kernel-team@meta.com \
    --cc=kpsingh@kernel.org \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=martin.lau@linux.dev \
    --cc=mattbobrowski@google.com \
    --cc=song@kernel.org \
    --cc=songliubraving@meta.com \
    --cc=viro@zeniv.linux.org.uk \
    /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;
as well as URLs for NNTP newsgroup(s).