[libvirt] [Qemu-devel] [PATCH 2/3] adlib: mark as insecure and deprecated.

[Philippe Mathieu-Daudé]

On 25/10/18 10:52, Gerd Hoffmann wrote:
> We have a lovely, guest-triggerable buffer overflow in opl2 emulation.
> 
> Reproducer:
>      outw(0xff60, 0x220);
>      outw(0x1020, 0x220);
>      outw(0xffb0, 0x220);
> Result:
>      Will overflow FM_OPL->AR_TABLE[] (see hw/audio/fmopl.[ch])
> 
> The specs google finds (http://www.symphoniae.com/Yamaha/YSC/YM3812.pdf)
> are rather sparse, possibly incomplete (looks like scanned fax with a
> scrambled page at the end) and not really helpful in identifying which
> of the register writes sets some illegal value.
> 
> So, go tag the device as deprecated with a warning messge, to notify

"warning message"

> users and schedule it for removal according to our deprecation policy.
> 
> Signed-off-by: Gerd Hoffmann <kraxel at redhat.com>
> ---
>   hw/audio/adlib.c     | 1 +
>   qemu-deprecated.texi | 4 ++++
>   2 files changed, 5 insertions(+)
> 
> diff --git a/hw/audio/adlib.c b/hw/audio/adlib.c
> index 97b876c..fb4a29c 100644
> --- a/hw/audio/adlib.c
> +++ b/hw/audio/adlib.c
> @@ -311,6 +311,7 @@ static void adlib_class_initfn (ObjectClass *klass, void *data)
>       set_bit(DEVICE_CATEGORY_SOUND, dc->categories);
>       dc->desc = ADLIB_DESC;
>       dc->props = adlib_properties;
> +    dc->deprecation_reason = "insecure, buffer overflow in opl2 emulation";
>   }
>   
>   static const TypeInfo adlib_info = {
> diff --git a/qemu-deprecated.texi b/qemu-deprecated.texi
> index 11b870c..7951a4f 100644
> --- a/qemu-deprecated.texi
> +++ b/qemu-deprecated.texi
> @@ -116,6 +116,10 @@ The @option{[hub_id name]} parameter tuple of the 'hostfwd_add' and
>   The ``ivshmem'' device type is replaced by either the ``ivshmem-plain''
>   or ``ivshmem-doorbell`` device types.
>   
> + at subsection adlib (since 3.1)
> +
> +Has known buffer overflow.
> +
>   @section System emulator machines
>   
>   @subsection pc-0.10 and pc-0.11 (since 3.0)
> 

Reviewed-by: Philippe Mathieu-Daudé <philmd at redhat.com>