[Qemu-devel] Re: [PATCH to consider for 0.12] vmware_vga: Don't crash on too-big DEFINE_CURSOR command

[Anthony Liguori]

Roland Dreier wrote:
>  > Thanks for the patch.  I'm planning on giving Dave Airlie's series a
>  > try for 0.12.0.  I'm pretty comfortable with those patches (since a
>  > few of them are mine :-)).  I also don't think vmware-vga is going to
>  > be reliable without them so I don't think pulling in the one fix is
>  > good enough.
>  > 
>  > His last patch has the same fix without the printf().  The printf is
>  > probably something to avoid since a malicious guest could create a
>  > storm of them.  Since libvirt logs stderr by default, the result could
>  > be pretty nasty.
>
> Fair enough... I just saw Dave's patches go by, and I guess we
> independently fixed the cursor size thing at right around the same time.
> How about the following, without the fprintf but with paranoid checks
> (since a malicious guest could send a bad DEFINE_CURSOR and do who knows
> what with the buffer overrun, which is even worse than spamming logs ;)
>   

Definitely seems reasonable.

Regards,

Anthony Liguori