Re: BK2CVS problem
From: Tomas Szepe
Date: Wed Nov 05 2003 - 19:58:03 EST
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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