code review 11094044: goprotobuf: fix integer overflows.

goprotobuf: fix integer overflows.

1) It's possible to panic the decoder by overflowing a length check.

2) (minor) the decoder was silently truncating varints that were larger than 64 bits. This isn't strictly a problem, but it could lead to a situation where a different decoder could decode a given message differently. Thus, if the message was vetted by one decoder and processed by another, an attacker could exploit this difference.

[agl1, 2013-07-10 13:17:46]

Hello golang-dev@googlegroups.com (cc: golang-dev@googlegroups.com),

I'd like you to review this change to
https://code.google.com/p/goprotobuf

[dsymonds, 2013-07-13 04:53:48]

LGTM

[dsymonds, 2013-07-13 04:55:35]

*** Submitted as
https://code.google.com/p/goprotobuf/source/detail?r=efc3fe235756 ***

goprotobuf: fix integer overflows.

1) It's possible to panic the decoder by overflowing a length check.

2) (minor) the decoder was silently truncating varints that were larger than 64
bits. This isn't strictly a problem, but it could lead to a situation where a
different decoder could decode a given message differently. Thus, if the message
was vetted by one decoder and processed by another, an attacker could exploit
this difference.

R=dsymonds
CC=golang-dev
https://codereview.appspot.com/11094044

Committer: David Symonds <dsymonds@golang.org>