OSV-2020-1022 Heap-buffer-overflow in ptls_set_negotiated_protocol

OSS-Fuzz report: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=13682 Crash type: Heap-buffer-overflow READ Crash state: ptlssetnegotiatedprotocol clienthandleencryptedextensions handlehandshakerecord...