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Date: Thu, 7 May 2009 10:38:51 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Roland McGrath <roland@redhat.com>,
       Andrew Morton <akpm@linux-foundation.org>,
       Chris Wright <chrisw@sous-sol.org>, linux-kernel@vger.kernel.org,
       Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: [RFC PATCH 3/3a] ptrace: add _ptrace_may_access()
Message-ID: <20090507083851.GA19133@elte.hu>
References: <20090505224729.GA965@redhat.com> <20090506080050.GF17457@elte.hu> <20090506235349.GC3756@redhat.com> <20090507002133.02D05FC39E@magilla.sf.frob.com> <20090507063606.GA15220@redhat.com> <20090507082027.GD12285@elte.hu> <20090507083102.GA20125@redhat.com>
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* Oleg Nesterov <oleg@redhat.com> wrote:

> On 05/07, Ingo Molnar wrote:
> >
> > * Oleg Nesterov <oleg@redhat.com> wrote:
> >
> > > /* the callers of ptrace_may_access should be fixed */
> > >
> > > 	int ptrace_may_access(struct task_struct *task, unsigned int mode)
> >
> > Sigh, NAK, for the reasons explained in the previous mails.
> 
> Agreed, but what about security_operations->ptrace_may_access ?
> 
> It has the same (bad) name, but returns the error code or 0 on 
> success.

Bad code should generally be fixed, or in exceptional circumstances 
it can tolerated if it's pre-existing bad code, but it should never 
be propagated. It has not spread _that_ widely yet, and is isolated 
to the security subsystem:

 include/linux/security.h
 security/capability.c
 security/commoncap.c
 security/root_plug.c
 security/security.c
 security/selinux/hooks.c
 security/smack/smack_lsm.c

	Ingo