Re: CVE-2009-2584

[Jack Steiner <steiner@sgi.com>]

On Thu, Nov 05, 2009 at 06:47:33PM +0100, Michael Buesch wrote:
> On Thursday 05 November 2009 18:38:21 Linus Torvalds wrote:
> > @@ -161,14 +161,15 @@ static int options_show(struct seq_file *s, void *p)
> >  static ssize_t options_write(struct file *file, const char __user *userbuf,
> >  			     size_t count, loff_t *data)
> >  {
> > -	unsigned long val;
> > -	char buf[80];
> > +	char buf[16];
> >  
> > -	if (strncpy_from_user(buf, userbuf, sizeof(buf) - 1) < 0)
> > +	if (count >= sizeof(buf))
> > +		return -EINVAL;
> > +	if (copy_from_user(buf, userbuf, count))
> >  		return -EFAULT;
> > -	buf[count - 1] = '\0';
> > -	if (!strict_strtoul(buf, 10, &val))
> > -		gru_options = val;
> > +	buf[count] = '\0';
> > +	if (strict_strtoul(buf, 0, &gru_options))
> > +		return -EINVAL;
> >  
> >  	return count;
> >  }
> > 
> > 
> 
> Looks OK to me. I can't test it however, as I don't own the hardware.

"buf" should be larger than 16. The string could be "0x" + 16 characters.

I'll verify the the rest.


We have the hardware :-)


--- jack