linux-kernel - Re: [PATCH 1/3] ipc: sysvsem: implement sys_unshare(CLONE

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <m13apkvmsa.fsf@frodo.ebiederm.org>
Date:	Thu, 17 Apr 2008 02:44:05 -0700
From:	ebiederm@...ssion.com (Eric W. Biederman)
To:	"Serge E. Hallyn" <serue@...ibm.com>
Cc:	lkml <linux-kernel@...r.kernel.org>, Andrew Morton <akpm@...l.org>,
	Pavel Emelyanov <xemul@...nvz.org>,
	Manfred Spraul <manfred@...orfullife.com>,
	Michael Kerrisk <mtk.manpages@...glemail.com>,
	Nadia Derbey <Nadia.Derbey@...l.net>
Subject: Re: [PATCH 1/3] ipc: sysvsem: implement sys_unshare(CLONE_SYSVSEM)

"Serge E. Hallyn" <serue@...ibm.com> writes:

> (patches 1 and 2 were originally by Manfred Spraul)
>
> sys_unshare(CLONE_NEWIPC) doesn't handle the undo lists properly, this can
> cause a kernel memory corruption. CLONE_NEWIPC must detach from the existing
> undo lists.
>
> Fix, part 1: add support for sys_unshare(CLONE_SYSVSEM)
>
> The original reason to not support it was the potential (inevitable?)
> confusion due to the fact that sys_unshare(CLONE_SYSVSEM) has the
> inverse meaning of clone(CLONE_SYSVSEM).
>
> Our two most reasonable options then appear to be (1) fully support
> CLONE_SYSVSEM, or (2) continue to refuse explicit CLONE_SYSVSEM,
> but always do it anyway on unshare(CLONE_SYSVSEM).  This patch does
> (1).
>
> Changelog:
> 	Apr 16: SEH: switch to Manfred's alternative patch which
> 		removes the unshare_semundo() function which
> 		always refused CLONE_SYSVSEM.
>
> Signed-off-by: Manfred Spraul <manfred@...orfullife.com>
> Signed-off-by: Serge E. Hallyn <serue@...ibm.com>

These patches look like the fix the core issue.

Acked-by: "Eric W. Biederman" <ebiederm@...ssion.com>

Eric
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/