Re: [PATCH 16/23] pefile: Parse a PE binary to find a key and asignature contained therein

[Kees Cook]

On Wed, Oct 31, 2012 at 5:31 AM, David Howells <dhowells@xxxxxxxxxx> wrote:
> Kees Cook <keescook@xxxxxxxxxxxx> wrote:
>
>> Which means this loop will walk past the end of the memory (loop is
>> bounded by n_sections, so secs[loop] can go past datalen). While
>> data_addr and raw_data_size will stay bounded, the read of sec->name
>> can be out of bounds.
>
> Assuming n_sections is checked, sec->name can't be out of bounds because it's
> a char array, not a pointer.
>
>> (Also, do you want a "break" in there after the first .keylist is found, or
>> is this intentionally "use last key list"?)
>
> Actually, no I don't.  The loop also checks the limits on each section - which
> I need to do since I have to individually digest the sections later.
>
> Attached is a patch I'm applying to pefile_parse_binary() to be more rigorous
> about the checking of values in the PE binary.

Cool; looks good to me. When this gets into linux-next, we should
probably spend more time staring at it. :)

Thanks for the fixes!

-Kees

-- 
Kees Cook
Chrome OS Security
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