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Message-ID: <8cb28ed5-b094-4b80-9373-40f93323250e@yandex.ru>
Date: Mon, 22 Apr 2024 23:18:52 +0300
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Subject: Re: [PATCH 2/2] openat2: add OA2_INHERIT_CRED flag
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To: Stefan Metzmacher <metze@samba.org>, linux-kernel@vger.kernel.org
Cc: Eric Biederman <ebiederm@xmission.com>,
 Alexander Viro <viro@zeniv.linux.org.uk>, Andy Lutomirski <luto@kernel.org>,
 Christian Brauner <brauner@kernel.org>, Jan Kara <jack@suse.cz>,
 Jeff Layton <jlayton@kernel.org>, Chuck Lever <chuck.lever@oracle.com>,
 Alexander Aring <alex.aring@gmail.com>, linux-fsdevel@vger.kernel.org,
 Paolo Bonzini <pbonzini@redhat.com>,
 =?UTF-8?Q?Christian_G=C3=B6ttsche?= <cgzones@googlemail.com>,
 Jens Axboe <axboe@kernel.dk>
References: <20240422084505.3465238-1-stsp2@yandex.ru>
 <20240422084505.3465238-2-stsp2@yandex.ru>
 <81ab6c6a-0a9e-4f2f-b455-7585283acf53@samba.org>
From: stsp <stsp2@yandex.ru>
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22.04.2024 22:53, Stefan Metzmacher пишет:
> I'm wondering if it would be better to capture the whole cred structure.
>
> Similar to io_register_personality(), which uses get_current_cred().
>
> Only using uid and gid, won't reflect any group memberships or 
> capabilities...
Hmm, I thought about that, but was
under an impression that with get_current_cred()
you only increment a refcount.
But I guess the trick here is that due
to an RCU machinery, you can actually
get your local copy if someone else
changes it?

I'll try what you say, thanks.