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Date:   Fri, 19 Jul 2019 12:29:41 +0200
From:   Christian Brauner <christian@brauner.io>
To:     "Dmitry V. Levin" <ldv@altlinux.org>
Cc:     Arnd Bergmann <arnd@arndb.de>, Aleksa Sarai <cyphar@cyphar.com>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Jeff Layton <jlayton@kernel.org>,
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        Shuah Khan <shuah@kernel.org>,
        Shuah Khan <skhan@linuxfoundation.org>,
        Eric Biederman <ebiederm@xmission.com>,
        Andy Lutomirski <luto@kernel.org>,
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Subject: Re: [PATCH v9 08/10] open: openat2(2) syscall
Message-ID: <20190719102932.274pvmxnrbjcc6gu@brauner.io>
References: <20190706145737.5299-1-cyphar@cyphar.com>
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On Fri, Jul 19, 2019 at 05:12:18AM +0300, Dmitry V. Levin wrote:
> On Thu, Jul 18, 2019 at 11:29:50PM +0200, Arnd Bergmann wrote:
> [...]
> > 5. you get the same problem with seccomp and strace that
> >    clone3() has -- these and others only track the register
> >    arguments by default.
> 
> Just for the record, this is definitely not the case for strace:
> it decodes arrays, structures, netlink messages, and so on by default.

There sure is value in trying to design syscalls that can be handled
nicely by seccomp but that shouldn't become a burden on designing
extensible syscalls.
I suggested a session for Ksummit where we can discuss if and how we can
make seccomp more compatible with pointer-args in syscalls.

Christian