This came up while addressing oss-fuzz issue
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=9335 in
envoyproxy#4171.

Without this PR, the server would shutdown non-gracefully, with TLS
posts still possible to deleted workerer thread dispatchers, resulting
in heap-user-after-free. Protobuf was throwing a CHECK exception, which
was not picked up as EnvoyException.

Risk level: Low
Testing: Unit tests added, corpus entry is in
envoyproxy#4171.

Signed-off-by: Harvey Tuch <htuch@google.com>

…4173)

This came up while addressing oss-fuzz issue
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=9335 in
#4171.

Without this PR, the server would shutdown non-gracefully, with TLS
posts still possible to deleted worker thread dispatchers, resulting
in heap-user-after-free. Protobuf was throwing a CHECK exception, which
was not picked up as EnvoyException.

Risk level: Low
Testing: Unit tests added, corpus entry is in #4171.

Signed-off-by: Harvey Tuch <htuch@google.com>

…#1938)

This is far from finished, but it reduces memory usage by ~10%.

Pulling the following changes from github.com/envoyproxy/envoy:

c1cc68d stats: refactoring MetricImpl without strings (envoyproxy#4190)
36809d8 fuzz: coverage profile generation instructions. (envoyproxy#4193)
ba40cc9 upstream: rebuild cluster when health check config is changed (envoyproxy#4075)
05c0d52 build: use clang-6.0. (envoyproxy#4168)
01f403e thrift_proxy: introduce header transport (envoyproxy#4082)
564d256 tcp: allow connection pool callers to store protocol state (envoyproxy#4131)
3e1d643 configs: match latest API changes (envoyproxy#4185)
bc6a10c Fix wrong mock function name. (envoyproxy#4187)
e994c1c Bump yaml-cpp so it builds with Visual Studio 15.8 (envoyproxy#4182)
3d1325e Converting envoy configs to V2 (envoyproxy#2957)
8d0680f Add timestamp to HealthCheckEvent definition (envoyproxy#4119)
497efb9 server: handle non-EnvoyExceptions safely if thrown in constructor. (envoyproxy#4173)
6d6fafd config: strengthen validation for gRPC config sources. (envoyproxy#4171)
132302c fuzz: reduce log level when running under fuzz engine. (envoyproxy#4161)
7c04ac2 test: fix V6EmptyOptions in coverage with IPv6 enable (envoyproxy#4155)
1b2219b ci: remove deprecated bazel --batch option (envoyproxy#4166)
2db6a4c ci: update clang to version 6.0 in the Ubuntu build image. (envoyproxy#4157)
71152b7 ratelimit: Add ratelimit custom response headers (envoyproxy#4015)
3062874 ssl: make Ssl::Connection const everywhere (envoyproxy#4179)
706e262 Handle validation of non expiring tokens in jwt_authn filter (envoyproxy#4007)
f06e958 fuzz: tag trivial fuzzers with no_fuzz. (envoyproxy#4156)
27fb1d3 thrift_proxy: add service name matching to router implementation (envoyproxy#4130)
8c189a5 Make over provisioning factor configurable (envoyproxy#4003)
6c08fb4 Making test less flaky (envoyproxy#4149)
592775b fuzz: bare bones HCM fuzzer. (envoyproxy#4118)

For istio/istio#7912.

Signed-off-by: Piotr Sikora <piotrsikora@google.com>