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Date: Thu, 20 Jan 2011 09:27:59 +0100
From: Paolo Bonzini <pbonzini@redhat.com>
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Subject: [Qemu-devel] Re: [PATCH] savevm: fix corruption in
	vmstate_subsection_load().
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To: Yoshiaki Tamura <tamura.yoshiaki@lab.ntt.co.jp>
Cc: aliguori@us.ibm.com, qemu-devel@nongnu.org, quintela@redhat.com

On 12/14/2010 10:07 AM, Yoshiaki Tamura wrote:
> Although it's rare to happen in live migration, when the head of a
> byte stream contains 0x05

IIUC, this happens if you have VMS_STRUCT and the field after the 
VMS_STRUCT starts with 0x5.

I think you should also add this in vmstate_subsection_load:

     sub_vmsd = vmstate_get_subsection(sub, idstr);
     if (sub_vmsd == NULL) {
         return -ENOENT;
     }
+   assert (!sub_vmsd->subsections);
     ret = vmstate_load_state(f, sub_vmsd, opaque, version_id);

and this in vmstate_load_state:

     if (field->flags & VMS_STRUCT) {
+       assert (!vmsd->subsections);
         ret = vmstate_load_state(f, field->vmsd, addr,
                                  field->vmsd->version_id);
     }

Paolo