From: Christoph Hellwig <hch@infradead.org>
To: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
Cc: Serge Hallyn <serge@hallyn.com>, Paul Moore <paul@paul-moore.com>,
Stephen Smalley <stephen.smalley.work@gmail.com>,
Eric Paris <eparis@parisplace.org>,
Frederick Lawler <fred@cloudflare.com>,
Jens Axboe <axboe@kernel.dk>,
Joseph Qi <joseph.qi@linux.alibaba.com>,
linux-security-module@vger.kernel.org, selinux@vger.kernel.org,
linux-block@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 0/2] capability: Introduce CAP_BLOCK_ADMIN
Date: Mon, 22 May 2023 23:18:46 -0700 [thread overview]
Message-ID: <ZGxaxnOeadVwb2gR@infradead.org> (raw)
In-Reply-To: <20230511070520.72939-1-tianjia.zhang@linux.alibaba.com>
On Thu, May 11, 2023 at 03:05:18PM +0800, Tianjia Zhang wrote:
> Separated fine-grained capability CAP_BLOCK_ADMIN from CAP_SYS_ADMIN.
> For backward compatibility, the CAP_BLOCK_ADMIN capability is included
> within CAP_SYS_ADMIN.
Splitting out capabilities tends to massivel break userspace. Don't
do it.
> CAP_SYS_ADMIN is required in the PR protocol implementation of existing
> block devices in the Linux kernel, which has too many sensitive
> permissions, which may lead to risks such as container escape. The
> kernel needs to provide more fine-grained permission management like
> CAP_NET_ADMIN to avoid online products directly relying on root to run.
I'm pretty sure the PR API can be keyed off just permissions on the
block device node as nothing in it is fundamentally unsafe.
Please work on relaxing the permissions checks there.
prev parent reply other threads:[~2023-05-23 6:19 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-05-11 7:05 [PATCH 0/2] capability: Introduce CAP_BLOCK_ADMIN Tianjia Zhang
2023-05-11 7:05 ` [PATCH 1/2] " Tianjia Zhang
2023-05-11 7:05 ` [PATCH 2/2] block: use block_admin_capable() for Persistent Reservations Tianjia Zhang
2023-05-11 16:17 ` [PATCH 0/2] capability: Introduce CAP_BLOCK_ADMIN Casey Schaufler
2023-05-16 12:05 ` Tianjia Zhang
2023-05-18 0:01 ` Casey Schaufler
2023-05-22 2:53 ` Tianjia Zhang
2023-05-22 19:13 ` Casey Schaufler
2023-05-23 3:05 ` Tianjia Zhang
2023-05-23 6:18 ` Christoph Hellwig [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=ZGxaxnOeadVwb2gR@infradead.org \
--to=hch@infradead.org \
--cc=axboe@kernel.dk \
--cc=eparis@parisplace.org \
--cc=fred@cloudflare.com \
--cc=joseph.qi@linux.alibaba.com \
--cc=linux-block@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-security-module@vger.kernel.org \
--cc=paul@paul-moore.com \
--cc=selinux@vger.kernel.org \
--cc=serge@hallyn.com \
--cc=stephen.smalley.work@gmail.com \
--cc=tianjia.zhang@linux.alibaba.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;
as well as URLs for NNTP newsgroup(s).