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To: "H. Peter Anvin" <hpa@zytor.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: Why does x86_64 support a SuSE-specific ioctl?
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From: Andi Kleen <ak@muc.de>
Date: 05 Oct 2002 17:00:13 +0200
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"H. Peter Anvin" <hpa@zytor.com> writes:
> > -
> > +		case TIOCGDEV:
> > +			return put_user (kdev_t_to_nr (real_tty->device), (unsigned int*) arg);
> 
> This is broken -- you're returning a dev_t as an unsigned int.  On
> i386 that means overwriting two bytes of userspace you shouldn't be,

The interface is defined as int, not as dev_t (see the ioctl defines)

I'm not aware of anybody proposing 64bit dev_t for the kernel, 
only 32bit dev_t, and the interface provides for that.

-Andi