Add mutex to CdmEngine for use of cert_provisioning_. am: 48bfaab32f am: 8ef7063d37

Original change: https://googleplex-android-review.googlesource.com/c/platform/vendor/widevine/+/21900046

Change-Id: Ifd3597f01ea72172065c44cf467248b63372a3f8
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

libwvdrmengine/cdm/core/include/cdm_engine.h

@@ -438,6 +438,8 @@ class CdmEngine {
   CdmSessionMap session_map_;
   CdmReleaseKeySetMap release_key_sets_;
   std::unique_ptr<CertificateProvisioning> cert_provisioning_;
+  // Lock must be acquired before using |cert_provisioning_|.
+  std::mutex cert_provisioning_mutex_;
   wvutil::FileSystem* file_system_;
   wvutil::Clock clock_;
   std::string spoid_;

libwvdrmengine/cdm/core/src/cdm_engine.cpp

@@ -65,7 +65,6 @@ class UsagePropertySet : public CdmClientPropertySet {
 CdmEngine::CdmEngine(wvutil::FileSystem* file_system,
                      std::shared_ptr<metrics::EngineMetrics> metrics)
     : metrics_(metrics),
-      cert_provisioning_(),
       file_system_(file_system),
       spoid_(EMPTY_SPOID),
       usage_session_(),
@@ -1064,6 +1063,7 @@ CdmResponseType CdmEngine::GetProvisioningRequest(
   }
 
   // TODO(b/141705730): Remove usage entries on provisioning.
+  std::unique_lock<std::mutex> cert_lock(cert_provisioning_mutex_);
   if (!cert_provisioning_) {
     cert_provisioning_.reset(
         new CertificateProvisioning(metrics_->GetCryptoMetrics()));
@@ -1093,6 +1093,7 @@ CdmResponseType CdmEngine::HandleProvisioningResponse(
     std::string* wrapped_key) {
   LOGI("response_size = %zu, security_level = %s", response.size(),
        RequestedSecurityLevelToString(requested_security_level));
+  std::unique_lock<std::mutex> cert_lock(cert_provisioning_mutex_);
   if (response.empty()) {
     LOGE("Empty provisioning response");
     cert_provisioning_.reset();