tree 8bdef88331026039493551517601e56fc492631a
parent ef19a2a994702a4b68d4658b9273a8b0a2616c9d
author Damien Neil <dneil@google.com> 1572646716 -0700
committer Damien Neil <dneil@google.com> 1572978690 +0000

reflect/protoreflect: remove nullability from repeated extension fields

Remove repeated extension fields from the set of nullable fields,
so that Has reports false and Range does not visit a a zero-length
repeated extension field.

This corrects a fuzzer-detected case where unmarshaling and remarshaling
a wire-format message could result in a semantic change. For a repeated
extension field in non-packed encoding, unmarshaling a packed
representation of the field would result in a message which Has the
extension. Remarshaling it would discard the the field.

Fixes golang.org/protobuf#975

Change-Id: Ie836559c93d218db5b5201742a3b8ebbaacf54ed
Reviewed-on: https://go-review.googlesource.com/c/protobuf/+/204897
Reviewed-by: Joe Tsai <thebrokentoaster@gmail.com>
Reviewed-by: Joe Tsai <joetsai@google.com>