From: Florian Weimer <fweimer@redhat.com>
To: "Mickaël Salaün" <mic@digikod.net>
Cc: Jeff Xu <jeffxu@google.com>, Al Viro <viro@zeniv.linux.org.uk>,
Christian Brauner <brauner@kernel.org>,
Kees Cook <keescook@chromium.org>,
Linus Torvalds <torvalds@linux-foundation.org>,
Paul Moore <paul@paul-moore.com>, Theodore Ts'o <tytso@mit.edu>,
Alejandro Colomar <alx@kernel.org>,
Aleksa Sarai <cyphar@cyphar.com>,
Andrew Morton <akpm@linux-foundation.org>,
Andy Lutomirski <luto@kernel.org>,
Arnd Bergmann <arnd@arndb.de>,
Casey Schaufler <casey@schaufler-ca.com>,
Christian Heimes <christian@python.org>,
Dmitry Vyukov <dvyukov@google.com>,
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Eric Chiang <ericchiang@google.com>,
Fan Wu <wufan@linux.microsoft.com>,
Geert Uytterhoeven <geert@linux-m68k.org>,
James Morris <jamorris@linux.microsoft.com>,
Jan Kara <jack@suse.cz>, Jann Horn <jannh@google.com>,
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Jordan R Abrahams <ajordanr@google.com>,
Lakshmi Ramasubramanian <nramas@linux.microsoft.com>,
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Luis Chamberlain <mcgrof@kernel.org>,
"Madhavan T . Venkataraman" <madvenka@linux.microsoft.com>,
Matt Bobrowski <mattbobrowski@google.com>,
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Miklos Szeredi <mszeredi@redhat.com>,
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Nicolas Bouchinet <nicolas.bouchinet@ssi.gouv.fr>,
Scott Shell <scottsh@microsoft.com>,
Shuah Khan <shuah@kernel.org>,
Stephen Rothwell <sfr@canb.auug.org.au>,
Steve Dower <steve.dower@python.org>,
Steve Grubb <sgrubb@redhat.com>,
Thibaut Sautereau <thibaut.sautereau@ssi.gouv.fr>,
Vincent Strubel <vincent.strubel@ssi.gouv.fr>,
Xiaoming Ni <nixiaoming@huawei.com>,
Yin Fengwei <fengwei.yin@intel.com>,
kernel-hardening@lists.openwall.com, linux-api@vger.kernel.org,
linux-fsdevel@vger.kernel.org, linux-integrity@vger.kernel.org,
linux-kernel@vger.kernel.org,
linux-security-module@vger.kernel.org
Subject: Re: [RFC PATCH v19 1/5] exec: Add a new AT_CHECK flag to execveat(2)
Date: Tue, 09 Jul 2024 12:05:50 +0200 [thread overview]
Message-ID: <87ed82283l.fsf@oldenburg.str.redhat.com> (raw)
In-Reply-To: <20240709.gae4cu4Aiv6s@digikod.net> ("Mickaël Salaün"'s message of "Tue, 9 Jul 2024 11:18:00 +0200")
* Mickaël Salaün:
>> > If we want to avoid that, we could have an agreed-upon error code which
>> > the LSM can signal that it'll never fail AT_CHECK checks, so we only
>> > have to perform the extra system call once.
>
> I'm not sure to follow. Either we check executable code or we don't,
> but it doesn't make sense to only check some parts (except for migration
> of user space code in a system, which is one purpose of the securebits
> added with the next patch).
>
> The idea with AT_CHECK is to unconditionnaly check executable right the
> same way it is checked when a file is executed. User space can decide
> to check that or not according to its policy (i.e. securebits).
I meant it purely as a performance optimization, to skip future system
calls if we know they won't provide any useful information for this
process. In the grand scheme of things, the extra system call probably
does not matter because we already have to do costly things like mmap.
Thanks,
Florian
next prev parent reply other threads:[~2024-07-09 10:06 UTC|newest]
Thread overview: 102+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-07-04 19:01 [RFC PATCH v19 0/5] Script execution control (was O_MAYEXEC) Mickaël Salaün
2024-07-04 19:01 ` [RFC PATCH v19 1/5] exec: Add a new AT_CHECK flag to execveat(2) Mickaël Salaün
2024-07-05 0:04 ` Kees Cook
2024-07-05 17:53 ` Mickaël Salaün
2024-07-08 19:38 ` Kees Cook
2024-07-05 18:03 ` Florian Weimer
2024-07-06 14:55 ` Mickaël Salaün
2024-07-06 15:32 ` Florian Weimer
2024-07-08 8:56 ` Mickaël Salaün
2024-07-08 16:37 ` [PATCH] binfmt_elf: Fail execution of shared objects with ELIBEXEC (was: Re: [RFC PATCH v19 1/5] exec: Add a new AT_CHECK flag to execveat(2)) Florian Weimer
2024-07-08 17:34 ` [PATCH] binfmt_elf: Fail execution of shared objects with ELIBEXEC Eric W. Biederman
2024-07-08 17:59 ` Florian Weimer
2024-07-10 10:05 ` [PATCH] binfmt_elf: Fail execution of shared objects with ELIBEXEC (was: Re: [RFC PATCH v19 1/5] exec: Add a new AT_CHECK flag to execveat(2)) Mickaël Salaün
2024-07-08 16:08 ` [RFC PATCH v19 1/5] exec: Add a new AT_CHECK flag to execveat(2) Jeff Xu
2024-07-08 16:25 ` Florian Weimer
2024-07-08 16:40 ` Jeff Xu
2024-07-08 17:05 ` Mickaël Salaün
2024-07-08 17:33 ` Florian Weimer
2024-07-08 17:52 ` Jeff Xu
2024-07-09 9:18 ` Mickaël Salaün
2024-07-09 10:05 ` Florian Weimer [this message]
2024-07-09 20:42 ` Mickaël Salaün
2024-07-09 18:57 ` Jeff Xu
2024-07-09 20:41 ` Mickaël Salaün
2024-07-06 8:52 ` Andy Lutomirski
2024-07-07 9:01 ` Mickaël Salaün
2024-07-17 6:33 ` Jeff Xu
2024-07-17 8:26 ` Steve Dower
2024-07-17 10:00 ` Mickaël Salaün
2024-07-18 1:02 ` Andy Lutomirski
2024-07-18 12:22 ` Mickaël Salaün
2024-07-20 1:59 ` Andy Lutomirski
2024-07-20 11:43 ` Jarkko Sakkinen
2024-07-23 13:16 ` Mickaël Salaün
2024-07-23 13:16 ` Mickaël Salaün
2024-07-18 1:51 ` Jeff Xu
2024-07-18 12:23 ` Mickaël Salaün
2024-07-18 22:54 ` Jeff Xu
2024-07-17 10:01 ` Mickaël Salaün
2024-07-18 2:08 ` Jeff Xu
2024-07-18 12:24 ` Mickaël Salaün
2024-07-18 13:03 ` James Bottomley
2024-07-18 15:35 ` Mickaël Salaün
2024-07-19 1:29 ` Jeff Xu
2024-07-19 8:44 ` Mickaël Salaün
2024-07-19 14:16 ` Jeff Xu
2024-07-19 15:04 ` Mickaël Salaün
2024-07-19 15:27 ` Jeff Xu
2024-07-23 13:15 ` Mickaël Salaün
2024-08-05 18:35 ` Jeff Xu
2024-08-09 8:45 ` Mickaël Salaün
2024-08-09 16:15 ` Jeff Xu
2024-07-19 15:12 ` Jeff Xu
2024-07-19 15:31 ` Mickaël Salaün
2024-07-19 17:36 ` Jeff Xu
2024-07-23 13:15 ` Mickaël Salaün
2024-07-18 14:46 ` enh
2024-07-18 15:35 ` Mickaël Salaün
2024-07-04 19:01 ` [RFC PATCH v19 2/5] security: Add new SHOULD_EXEC_CHECK and SHOULD_EXEC_RESTRICT securebits Mickaël Salaün
2024-07-05 0:18 ` Kees Cook
2024-07-05 17:54 ` Mickaël Salaün
2024-07-05 21:44 ` Kees Cook
2024-07-05 22:22 ` Jarkko Sakkinen
2024-07-06 14:56 ` Mickaël Salaün
2024-07-06 17:28 ` Jarkko Sakkinen
2024-07-06 14:56 ` Mickaël Salaün
2024-07-18 14:16 ` Roberto Sassu
2024-07-18 16:20 ` Mickaël Salaün
2024-07-08 16:17 ` Jeff Xu
2024-07-08 17:53 ` Jeff Xu
2024-07-08 18:48 ` Mickaël Salaün
2024-07-08 21:15 ` Jeff Xu
2024-07-08 21:25 ` Steve Dower
2024-07-08 22:07 ` Jeff Xu
2024-07-09 20:42 ` Mickaël Salaün
2024-07-09 21:57 ` Jeff Xu
2024-07-10 9:58 ` Mickaël Salaün
2024-07-10 16:26 ` Kees Cook
2024-07-11 8:57 ` Mickaël Salaün
2024-07-16 15:02 ` Jeff Xu
2024-07-16 15:10 ` Steve Dower
2024-07-16 15:15 ` Mickaël Salaün
2024-07-16 15:18 ` Jeff Xu
2024-07-10 16:32 ` Steve Dower
2024-07-20 2:06 ` Andy Lutomirski
2024-07-23 13:15 ` Mickaël Salaün
2024-07-04 19:01 ` [RFC PATCH v19 3/5] selftests/exec: Add tests for AT_CHECK and related securebits Mickaël Salaün
2024-07-04 19:01 ` [RFC PATCH v19 4/5] selftests/landlock: Add tests for execveat + AT_CHECK Mickaël Salaün
2024-07-04 19:01 ` [RFC PATCH v19 5/5] samples/should-exec: Add set-should-exec Mickaël Salaün
2024-07-08 19:40 ` Mimi Zohar
2024-07-09 20:42 ` Mickaël Salaün
2024-07-08 20:35 ` [RFC PATCH v19 0/5] Script execution control (was O_MAYEXEC) Mimi Zohar
2024-07-09 20:43 ` Mickaël Salaün
2024-07-16 15:57 ` Roberto Sassu
2024-07-16 16:12 ` James Bottomley
2024-07-16 17:31 ` Mickaël Salaün
2024-07-18 16:21 ` Mickaël Salaün
[not found] ` <E608EDB8-72E8-4791-AC9B-8FF9AC753FBE@sempervictus.com>
2024-07-16 17:47 ` Mickaël Salaün
2024-07-17 17:59 ` Boris Lukashev
2024-07-18 13:00 ` Mickaël Salaün
2024-07-15 20:16 ` Jonathan Corbet
2024-07-16 7:13 ` Mickaël Salaün
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