Re: [Qemu-devel] [PATCH v4 12/30] vmstate: fix buffer overflow in target-arm/machine.c

[Michael S. Tsirkin]

On Mon, Mar 31, 2014 at 04:40:41PM +0100, Peter Maydell wrote:
> On 31 March 2014 15:16, Michael S. Tsirkin <address@hidden> wrote:
> > CVE-2013-4531
> >
> > cpreg_vmstate_indexes is a VARRAY_INT32. A negative value for
> > cpreg_vmstate_array_len will cause a buffer overflow.
> >
> > VMSTATE_INT32_LE was supposed to protect against this
> > but doesn't because it doesn't validate that input is
> > non-negative.
> >
> > Fix this macro to valide the value appropriately.
> >
> > The only other user of VMSTATE_INT32_LE doesn't
> > ever use negative numbers so it doesn't care.
> 
> This fixes the bug, but it's rather unintuitive semantics
> for an INT32_LE not to simply do a signed comparison...
> Maybe rename the macro?
> 
> thanks
> -- PMM

Sure. I'll do it in a separate patch though.