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From: "Jason A. Donenfeld" <Jason@zx2c4.com>
To: Kernel Hardening <kernel-hardening@lists.openwall.com>,
	Andy Lutomirski <luto@amacapital.net>
Cc: LKML <linux-kernel@vger.kernel.org>, Jann Horn <jann@thejh.net>,
	Christian Brauner <christian.brauner@canonical.com>
Subject: Re: forkat(int pidfd), execveat(int pidfd), other awful things?
Date: Mon, 1 Feb 2021 18:51:45 +0100	[thread overview]
Message-ID: <CAHmME9rDC9ObAT=6CJ3h0KQ9ogHsrnDNMnocm5882A2j6OPF6g@mail.gmail.com> (raw)
In-Reply-To: <CAHmME9oHBtR4fBBUY8E_Oi7av-=OjOGkSNhQuMJMHhafCjazBw@mail.gmail.com>

> int execve_parent(int parent_pidfd, int root_dirfd, int cgroup_fd, int
> namespace_fd, const char *pathname, char *const argv[], char *const
> envp[]);

A variant on the same scheme would be:

int execve_remote(int pidfd, int root_dirfd, int cgroup_fd, int
namespace_fd, const char *pathname, char *const argv[], char *const
envp[]);

Unpriv'd process calls fork(), and from that fork sends its pidfd
through a unix socket to systemd-sudod, which then calls execve_remote
on that pidfd.

There are a lot of (potentially very bad) ways to skin this cat.

  reply	other threads:[~2021-02-01 17:59 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-02-01 17:47 forkat(int pidfd), execveat(int pidfd), other awful things? Jason A. Donenfeld
2021-02-01 17:51 ` Jason A. Donenfeld [this message]
2021-02-01 18:20 ` Christian Brauner
2021-02-01 18:29 ` Andy Lutomirski
2021-02-02  9:23   ` David Laight
2021-07-28 16:37     ` Leveraging pidfs for process creation without fork John Cotton Ericson
2021-07-29 14:24       ` Christian Brauner
2021-07-29 14:54         ` John Ericson
2021-07-30  1:41         ` Al Viro
     [not found]           ` <1468d75c-57ae-42aa-85ce-2bee8d403763@www.fastmail.com>
2021-07-31 22:42             ` Al Viro
2021-08-02 12:19               ` Christian Brauner
2021-08-03  6:00                 ` John Cotton Ericson
2021-02-01 18:32 ` forkat(int pidfd), execveat(int pidfd), other awful things? Casey Schaufler

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