Re: BK2CVS problem

[Tomas Szepe]

On Nov-05 2003, Wed, 15:03 -0800
Larry McVoy <lm@xxxxxxxxxxxx> wrote:

> > > > +       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.

Also note the extra parentheses to avoid a gcc warning.

-- 
Tomas Szepe <szepe@xxxxxxxxxxxxxxx>
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