Re: [PATCH] drivers/char/mem.c: Add /dev/ioports, supporting 16-bit and 32-bit ports

[Josh Triplett]

On Sat, May 10, 2014 at 09:07:42AM +0200, Jann Horn wrote:
> On Fri, May 09, 2014 at 12:19:16PM -0700, Josh Triplett wrote:
> > +	if (port > 65535)
> > +		return 0;
> > +	switch (count) {
> [...]
> > +	case 4:
> > +		if (__put_user(inl(port), buf) < 0)
> > +			return -EFAULT;
> 
> What if I attempt a four-byte read at 65535? That would access four
> out-of-bounds bytes, right?

No, it would do an ind instruction on port 65535.

- Josh Triplett
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/