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Re: [Libguestfs] [PATCH v2 1/2] lib: change how hbin sections are read.



On Wed, Feb 15, 2017 at 02:28:41PM -0500, Dawid Zamirski wrote:
> Correct, however there's also no guarantee that seeking by 4k in
> "garbage" data would not land you in registry data that happens to
> evaluate to "hbin" as well. That's why I put "hbin" offset validation
> check couple of lines below to make sure that the "hbin" we found by
> searching is a proper one. The offset check I'm referring to is:
> 
> /* get "stated" hbin offset from header */
> size_t page_offset = le32to(page->offset_first) + 0x1000;
> 
> /* if that does not match our current file offset,
>    then exit with error */
> if (page_offset != off) { 
>   SET_ERRNO...
> }

Still, what kind of corruption would move a genuine hbin to a
non-page-sized offset in the file?  It seems unlikely to me ...

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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