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

[Daniel P . Berrangé]

On Thu, Oct 25, 2018 at 04:26:16PM +0530, P J P wrote:
> +-- On Thu, 25 Oct 2018, 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])
> 
> + Reported-by: Wangjunqing <address@hidden>

So you have a CVE number for this ?

If so, it should be referenced in the commit message too, even if
we can't fix the problem.

> | 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.
> |  
> | address@hidden adlib (since 3.1)
> | +
> | +Has known buffer overflow.

It would be good to give a recommendation to a better choice to
replace its usage

> | +
> |  @section System emulator machines
> |  
> |  @subsection pc-0.10 and pc-0.11 (since 3.0)

Regards,
Daniel
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