linux-kernel - Re: [PATCH 9/9] make net/core/scm.c uid comparisons user namespace aware

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: <20111018232242.GA22950@hallyn.com>
Date:	Tue, 18 Oct 2011 23:22:42 +0000
From:	"Serge E. Hallyn" <serge@...lyn.com>
To:	Joe Perches <joe@...ches.com>
Cc:	linux-kernel@...r.kernel.org, ebiederm@...ssion.com,
	akpm@...ux-foundation.org, oleg@...hat.com, richard@....at,
	mikevs@...all.net, segoon@...nwall.com, gregkh@...e.de,
	dhowells@...hat.com, eparis@...hat.com,
	"Serge E. Hallyn" <serge.hallyn@...onical.com>,
	netdev@...r.kernel.org
Subject: Re: [PATCH 9/9] make net/core/scm.c uid comparisons user namespace
 aware

Quoting Joe Perches (joe@...ches.com):
> On Tue, 2011-10-18 at 21:54 +0000, Serge Hallyn wrote:
> > From: "Serge E. Hallyn" <serge.hallyn@...onical.com>
> 
> Hi Serge.
> 
> Just some trivial style notes.
> 
> > Currently uids are compared without regard for the user namespace.
> > Fix that to prevent tasks in a different user namespace from
> > wrongly matching on SCM_CREDENTIALS.
> []
> > diff --git a/net/core/scm.c b/net/core/scm.c
> 
> > -static __inline__ int scm_check_creds(struct ucred *creds)
> > +static __inline__ bool uidequiv(const struct cred *src, struct ucred *tgt,
> > +			       struct user_namespace *ns)
> 
> Perhaps inline is better than __inline__ and do these
> functions really need to be marked inline at all?

Dunno, I was just sticking with the current style.

> > +{
> > +	if (src->user_ns != ns)
> > +		goto check_capable;
> > +	if (src->uid == tgt->uid || src->euid == tgt->uid ||
> > +	    src->suid == tgt->uid)
> 
> Perhaps this is less prone to typo errors and are a bit
> more readable as:
> 
> 	if (tgt->uid == src->uid ||
> 	    tgt->uid == src->euid ||
> 	    tgt->uid == src->suid)

I do like that better.

thanks,
-serge
--
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/