Re: [quicwg/base-drafts] QPACK Required Insert Count decoding pseudocode does not enforce that encoding is valid (#2892)

Bence Béky <notifications@github.com> Fri, 12 July 2019 00:51 UTC

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Subject: Re: [quicwg/base-drafts] QPACK Required Insert Count decoding pseudocode does not enforce that encoding is valid (#2892)
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Another bogus encoder output is:
MaxEntries = 8
TotalNumberOfInserts = 8
EncInsertCount = 1

Now MaxValue = 16, MaxWrapped = 16, so `if ReqInsertCount > MaxValue` branch is hit.  ReqInsertCount ends up being 0, just like above, so EncInsertCount should have been 0.  This particular case can be handled by replacing `if ReqInsertCount < FullRange` by `if ReqInsertCount <= FullRange`, but this does not fix the first test case above.

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