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From: Christoph Hellwig <hch@lst.de>
To: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>,
	Al Viro <viro@zeniv.linux.org.uk>, Jens Axboe <axboe@kernel.dk>,
	Christoph Hellwig <hch@lst.de>, Kees Cook <keescook@chromium.org>,
	LKML <linux-kernel@vger.kernel.org>
Subject: Re: Does uaccess_kernel() work for detecting kernel thread?
Date: Tue, 5 Jan 2021 08:57:31 +0100	[thread overview]
Message-ID: <20210105075731.GB30414@lst.de> (raw)
In-Reply-To: <87a6u5iw3d.fsf@x220.int.ebiederm.org>

On Tue, Dec 22, 2020 at 11:33:58AM -0600, Eric W. Biederman wrote:
> I do wonder though if perhaps we should create a is_user_cred helper to
> detect the difference between the creds of kernel threads and the thread
> of ordinary userspace.   Which would handle io_uring that copy creds
> around and check them at a later time more cleanly.

I don't think we should as no one has a business to check this difference.
If there is a case where the creds are not correct for all access decisions
we need to fix that rather than adding hacks.

  reply	other threads:[~2021-01-05  7:58 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-12-22 14:39 Tetsuo Handa
2020-12-22 17:33 ` Eric W. Biederman
2021-01-05  7:57   ` Christoph Hellwig [this message]
2020-12-23  7:53 ` Christoph Hellwig
2020-12-23 10:11   ` Tetsuo Handa
2021-01-05  7:59     ` Christoph Hellwig
2021-01-05 10:11       ` Tetsuo Handa

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