From: Oleg Nesterov <oleg@redhat.com>
To: Solar Designer <solar@openwall.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
Djalal Harouni <tixxdz@opendz.org>,
linux-kernel@vger.kernel.org,
kernel-hardening@lists.openwall.com,
Andrew Morton <akpm@linux-foundation.org>,
Al Viro <viro@zeniv.linux.org.uk>,
Alexey Dobriyan <adobriyan@gmail.com>,
"Eric W. Biederman" <ebiederm@xmission.com>,
Vasiliy Kulikov <segoon@openwall.com>,
Kees Cook <keescook@chromium.org>,
WANG Cong <xiyou.wangcong@gmail.com>,
James Morris <james.l.morris@oracle.com>,
linux-security-module@vger.kernel.org,
linux-fsdevel@vger.kernel.org,
Alan Cox <alan@lxorguk.ukuu.org.uk>,
Greg KH <gregkh@linuxfoundation.org>, Ingo Molnar <mingo@elte.hu>,
Stephen Wilson <wilsons@start.ca>,
"Jason A. Donenfeld" <Jason@zx2c4.com>
Subject: Re: exec_id protection from bad child exit signals (was: Re: [PATCH 0/9] proc: protect /proc/<pid>/* files across execve)
Date: Sun, 11 Mar 2012 19:20:07 +0100 [thread overview]
Message-ID: <20120311182007.GA5601@redhat.com> (raw)
In-Reply-To: <20120311103532.GA26980@openwall.com>
On 03/11, Solar Designer wrote:
>
> Actually, the original/historical purpose of the exec_id stuff was to
> protect privileged parent processes (those having done a SUID/SGID exec)
> from non-standard child exit signals, which could be set with clone().
> I think we may want to audit the current implementation and see if it
> still fully achieves the goal or maybe not (and fix it if not).
Funny that, I noticed this message only after I sent the question about
the current exec_id stuff.
> I include below pieces of the prototype implementation from
> linux-2.2.12-ow6.tar.gz released in 1999.
Perhaps I missed something, but ignoring the "cap_raised" issues, this
all is very simple. de_thread() should simply do:
current->exit_signal = SIGCHLD;
read_lock(&tasklist_lock);
list_for_each_entry(p, ¤t->children, sibling)
p->exit_signal = SIGCHILD;
read_unlock(&tasklist_lock);
The only problem is CLONE_PARENT.
Oleg.
next prev parent reply other threads:[~2012-03-11 18:20 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-03-10 23:25 [PATCH 0/9] proc: protect /proc/<pid>/* files across execve Djalal Harouni
2012-03-10 23:25 ` [PATCH 1/9] exec: add a global execve counter Djalal Harouni
2012-03-11 0:12 ` Linus Torvalds
2012-03-11 0:36 ` Linus Torvalds
2012-03-11 0:58 ` Linus Torvalds
2012-03-11 8:24 ` Solar Designer
2012-03-11 9:56 ` Ingo Molnar
2012-03-11 14:03 ` Alan Cox
2012-03-11 17:15 ` Djalal Harouni
2012-03-11 8:39 ` Djalal Harouni
2012-03-11 9:40 ` Solar Designer
2012-03-11 17:25 ` Oleg Nesterov
2012-03-11 17:49 ` self_exec_id/parent_exec_id && CLONE_PARENT Oleg Nesterov
2012-03-11 18:02 ` Linus Torvalds
2012-03-11 18:37 ` richard -rw- weinberger
2012-03-11 18:39 ` Oleg Nesterov
2012-03-14 18:55 ` [PATCH 0/1] (Was: self_exec_id/parent_exec_id && CLONE_PARENT) Oleg Nesterov
2012-03-14 18:55 ` [PATCH 1/1] CLONE_PARENT shouldn't allow to set ->exit_signal Oleg Nesterov
2012-03-18 18:25 ` Linus Torvalds
2012-03-18 20:53 ` Oleg Nesterov
2012-03-11 22:48 ` [PATCH 1/9] exec: add a global execve counter Linus Torvalds
2012-03-11 23:32 ` Djalal Harouni
2012-03-11 23:42 ` Linus Torvalds
2012-03-12 0:25 ` Djalal Harouni
2012-03-12 10:11 ` Linus Torvalds
2012-03-12 14:01 ` Djalal Harouni
2012-03-11 23:36 ` Djalal Harouni
2012-03-12 14:34 ` Oleg Nesterov
2012-03-10 23:25 ` [PATCH 2/9] proc: add proc_file_private struct to store private information Djalal Harouni
2012-03-10 23:25 ` [PATCH 3/9] proc: new proc_exec_id_ok() helper function Djalal Harouni
2012-03-10 23:25 ` [PATCH 4/9] proc: protect /proc/<pid>/* INF files from reader across execve Djalal Harouni
2012-03-10 23:25 ` [PATCH 5/9] proc: add protection support for /proc/<pid>/* ONE files Djalal Harouni
2012-03-10 23:25 ` [PATCH 6/9] proc: protect /proc/<pid>/* ONE files from reader across execve Djalal Harouni
2012-03-10 23:25 ` [PATCH 7/9] proc: protect /proc/<pid>/{maps,smaps,numa_maps} Djalal Harouni
2012-03-10 23:25 ` [PATCH 8/9] proc: protect /proc/<pid>/{environ,pagemap} across execve Djalal Harouni
2012-03-11 8:05 ` Alexey Dobriyan
2012-03-11 17:01 ` Djalal Harouni
2012-03-10 23:25 ` [PATCH 9/9] proc: improve and clean up /proc/<pid>/mem protection Djalal Harouni
2012-03-11 0:01 ` [PATCH 0/9] proc: protect /proc/<pid>/* files across execve Linus Torvalds
2012-03-11 0:27 ` Djalal Harouni
2012-03-11 8:46 ` Djalal Harouni
2012-03-11 10:35 ` exec_id protection from bad child exit signals (was: Re: [PATCH 0/9] proc: protect /proc/<pid>/* files across execve) Solar Designer
2012-03-11 18:20 ` Oleg Nesterov [this message]
2012-03-12 19:13 ` [PATCH 0/9] proc: protect /proc/<pid>/* files across execve Eric W. Biederman
2012-03-12 20:44 ` Djalal Harouni
2012-03-12 21:47 ` Eric W. Biederman
2012-03-12 22:41 ` Djalal Harouni
2012-03-12 23:10 ` Eric W. Biederman
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