Re: [Qemu-devel] [PATCH 8/8] qcow2: Read outside array bounds in qcow2_pre_write_overlap_check()

[Eric Blake]

On 08/31/2018 08:32 AM, Liam Merwick wrote:

> > The fix looks correct, but to prevent the problem from happening 
> > again, I'd suggest you also add a compile-time BUG_ON that fails if 
> > the array size gets out of sync again due to another addition of 
> > another overlap detection bit.
>
> Good idea. There is no generic BUG_ON in QEMU (just a few private 
> copies) or BUILD_BUG_ON. I can add a commit that introduces a copy of 
> include/linux/build_bug.h from the Linux kernel and use BUILD_BUG_ON in 
> this commit.  Is there any reason not to do that?

We already have the generic QEMU_BUILD_BUG_ON() used throughout the 
tree; that's the one to use here, rather than adding yet another macro 
with a similar functionality.

--
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org