From: Jarkko Sakkinen <jarkko@kernel.org>
To: Andrey Ryabinin <arbn@yandex-team.ru>,
David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>,
"Serge E. Hallyn" <serge@hallyn.com>,
keyrings@vger.kernel.org, linux-security-module@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] keys: Allow disabling read permissions for key possessor
Date: Tue, 23 Mar 2021 04:02:15 +0200 [thread overview]
Message-ID: <YFlMJ12+3/MpYixW@kernel.org> (raw)
In-Reply-To: <20210322095726.14939-1-arbn@yandex-team.ru>
On Mon, Mar 22, 2021 at 12:57:26PM +0300, Andrey Ryabinin wrote:
> keyctl_read_key() has a strange code which allows possessor to read
> key's payload regardless of READ permission status:
>
> $ keyctl add user test test @u
> 196773443
> $ keyctl print 196773443
> test
> $ keyctl describe 196773443
> 196773443: alswrv-----v------------ 1000 1000 user: test
> $ keyctl rdescribe 196773443
> user;1000;1000;3f010000;test
> $ keyctl setperm 196773443 0x3d010000
> $ keyctl describe 196773443
> 196773443: alsw-v-----v------------ 1000 1000 user: test
> $ keyctl print 196773443
> test
>
> The last keyctl print should fail with -EACCESS instead of success.
> Fix this by removing weird possessor checks.
>
> Signed-off-by: Andrey Ryabinin <arbn@yandex-team.ru>
I wrote a new test. If you include a test into a commit please
describe it so that it can be easily executed. Otherwise, it is
somewhat useless.
Anyway,
https://gist.github.com/jarkk0sakkinen/7b417be20cb52ed971a90561192f0883
David, why all of these end up allowing to still print the payload?
/Jarkko
prev parent reply other threads:[~2021-03-23 2:03 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-22 9:57 [PATCH] keys: Allow disabling read permissions for key possessor Andrey Ryabinin
2021-03-23 0:55 ` Eric Biggers
2021-03-23 2:02 ` Jarkko Sakkinen [this message]
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