qemu-devel
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Qemu-devel] [PATCH] ide: refuse WIN_READ_NATIVE_MAX on empty device


From: Markus Armbruster
Subject: Re: [Qemu-devel] [PATCH] ide: refuse WIN_READ_NATIVE_MAX on empty device
Date: Fri, 05 Apr 2013 12:56:07 +0200
User-agent: Gnus/5.13 (Gnus v5.13) Emacs/24.1 (gnu/linux)

Stefan Hajnoczi <address@hidden> writes:

> What is the highest addressable sector on an empty CD-ROM?  Nothing is
> addressable so produce an error.
>
> This patch prevents a divide-by-zero in ide_set_sector() since
> s->sectors and s->heads would be 0.  Not to mention that a sector=-1
> argument would be nonsense.
>
> Note that WIN_READ_NATIVE_MAX can be triggered using hdparm -N 1024
> /dev/cdrom.  The LBA bit will be set to 1 though, so the only easy way
> to go down the ide_set_sector() CHS code path which divides by zero is
> to comment out the s->select & 0x40 case for testing.

Suggests you did that.

Have you tried the reproducer with a physical drive?  Does it fail the
command when empty, too?



reply via email to

[Prev in Thread] Current Thread [Next in Thread]