Re: Signed divides vs shifts (Re: [Security] /dev/urandom usesuninit bytes, leaks user data)

[Eric Dumazet]

On Mon, 17 Dec 2007 10:05:35 -0800
"Ray Lee" <ray-lk@xxxxxxxxxxxxx> wrote:

> On Dec 17, 2007 9:55 AM, Eric Dumazet <dada1@xxxxxxxxxxxxx> wrote:
> > -               mid = (last - first) / 2 + first;
> > +       while (low <= high) {
> > +               mid = (low + high) / 2;
> 
> I think you just introduced a bug. Think about what happens if
> low=high=MAX_LONG/2 + 1.
> 

Fortunatly this is not possible :)

Hint : sizeof(struct exception_table_entry) is >= 8

so high is garanteed to be <= MAX_LONG/8

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