linux-kernel - Re: [PATCH 5/9] Allow ptrace from non-init user namespaces

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: <3016.1298481061@redhat.com>
Date:	Wed, 23 Feb 2011 17:11:01 +0000
From:	David Howells <dhowells@...hat.com>
To:	"Serge E. Hallyn" <serge@...lyn.com>
Cc:	dhowells@...hat.com, LSM <linux-security-module@...r.kernel.org>,
	Andrew Morton <akpm@...l.org>,
	James Morris <jmorris@...ei.org>,
	Kees Cook <kees.cook@...onical.com>,
	containers@...ts.linux-foundation.org,
	kernel list <linux-kernel@...r.kernel.org>,
	"Eric W. Biederman" <ebiederm@...ssion.com>,
	Alexey Dobriyan <adobriyan@...il.com>,
	Michael Kerrisk <mtk.manpages@...il.com>, xemul@...allels.com
Subject: Re: [PATCH 5/9] Allow ptrace from non-init user namespaces

Serge E. Hallyn <serge@...lyn.com> wrote:

> +int same_or_ancestor_user_ns(struct task_struct *task,
> +	struct task_struct *victim)
> +{
> +	struct user_namespace *u1 = task_cred_xxx(task, user)->user_ns;
> +	struct user_namespace *u2 = task_cred_xxx(victim, user)->user_ns;

Hmmm.  task_cred_xxx() uses task->real_cred, which is correct for victim (the
object), but normally you'd use task->cred for task (the subject).  However,
in this case, I think it's probably okay.

David
--
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/