Subject: [6lo] [Errata Verified] RFC8163 (5996)

From: RFC Errata System <[email-masked]>
Date: Thu, 5 Aug 2021 22:28:19 -0700 (PDT)

The following errata report has been verified for RFC8163,
"Transmission of IPv6 over Master-Slave/Token-Passing (MS/TP) Networks". 

--------------------------------------
You may review the report below and at:
https://www.rfc-editor.org/errata/eid5996

--------------------------------------
Status: Verified
Type: Technical

Reported by: Kerry Lynn <[email-masked]>
Date Reported: 2020-02-27
Verified by: Erik Kline (IESG)

Section: Appendix B.

Original Text
-------------
       /*
        * Sanity check the encoding to prevent the while() loop below
        * from overrunning the output buffer.
        */
       if (read_index + code > length)
         return 0;

Corrected Text
--------------
       /*
        * Sanity check the encoding to prevent the while() loop below
        * from overrunning the output buffer.
        */
       if (code == 0 || read_index + code > length)
         return 0;

Notes
-----
This was submitted as a change to [BACnet], Annex T, by James Butler.  The normative procedure for decoding COBS is correct in [BACnet], 9.10.3.2(a) but this bug appears in the informative example in Annex T.  Since the purpose of COBS encoding is to eliminate all zero bytes from the data, the presence of a zero indicates an error.

--------------------------------------
RFC8163 (draft-ietf-6lo-6lobac-08)
--------------------------------------
Title               : Transmission of IPv6 over Master-Slave/Token-Passing (MS/TP) Networks
Publication Date    : May 2017
Author(s)           : K. Lynn, Ed., J. Martocci, C. Neilson, S. Donaldson
Category            : PROPOSED STANDARD
Source              : IPv6 over Networks of Resource-constrained Nodes
Area                : Internet
Stream              : IETF
Verifying Party     : IESG