Date: Wed, 5 Nov 2003 15:03:50 -0800
From: Larry McVoy <lm@bitmover.com>
To: Chad Kitching <CKitching@powerlandcomputers.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: BK2CVS problem
Message-ID: <20031105230350.GB12992@work.bitmover.com>
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	Chad Kitching <CKitching@powerlandcomputers.com>,
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References: <18DFD6B776308241A200853F3F83D507169CBC@pl6w2kex.lan.powerlandcomputers.com>
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On Wed, Nov 05, 2003 at 04:48:09PM -0600, Chad Kitching wrote:
> From: Zwane Mwaikambo
> > > +       if ((options == (__WCLONE|__WALL)) && (current->uid = 0))
> > > +                       retval = -EINVAL;
> > 
> > That looks odd
> > 
> 
> Setting current->uid to zero when options __WCLONE and __WALL are set?  The 
> retval is dead code because of the next line, but it looks like an attempt
> to backdoor the kernel, does it not?

It sure does.  Note "current->uid = 0", not "current->uid == 0". 
Good eyes, I missed that.  This function is sys_wait4() so by passing in
__WCLONE|__WALL you are root.  How nice.
-- 
---
Larry McVoy              lm at bitmover.com          http://www.bitmover.com/lm
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