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Date: Fri, 28 May 2010 11:39:20 -0700
From: Kees Cook <kees.cook@canonical.com>
To: "Serge E. Hallyn" <serue@us.ibm.com>
Cc: linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org,
       linux-doc@vger.kernel.org, Randy Dunlap <rdunlap@xenotime.net>,
       Andrew Morton <akpm@linux-foundation.org>,
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       Peter Zijlstra <a.p.zijlstra@chello.nl>,
       "Eric W. Biederman" <ebiederm@xmission.com>,
       Tim Gardner <tim.gardner@canonical.com>
Subject: Re: [PATCH] fs: block cross-uid sticky symlinks
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 <20100528044026.GA13636@us.ibm.com>
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Hi,

On Thu, May 27, 2010 at 11:40:26PM -0500, Serge E. Hallyn wrote:
> > +	if (S_ISLNK(inode->i_mode) &&
> 
> Q: is the S_ISLNK() check actually needed?

I guess not -- I would imagine this function would never be called if it
wasn't true, and the caller would probably run into bigger problems first
anyway.  I will drop this test.

Thanks,

-Kees

-- 
Kees Cook
Ubuntu Security Team