commit 77c12e0fbd8d7f1eb0976a52f7d8f4849fb87d44
author Lee Shombert <shombert@google.com> Wed Oct 30 16:06:06 2024 -0700
committer Lee Shombert <shombert@google.com> Thu Oct 31 22:15:16 2024 +0000
tree 0693fd96fac555e75a57aee3fc4a5140af6d3cd5
parent a4dc88d7199beb4416663c581e070c08ff20ace1

Exclude the PIC key package_info from shared memory

The PIC key package_info is being sniffed as a sysprop outside of the
cache infrastructure, so it cannot be moved into shared memory yet.
This change excludes that one key from shared memory (when the feature
flag is enabled).

This is expected to be temporary until a mechanism is provided to
clients to sniff nonce changes in controlled way.

This change also corrects the bug numbers in the trunk stable flags
related to this effort.

Tested by booting an image with the flag enabled and verifying that
the package_info cache key exists as a system property, but other
system_server cache keys are not properties.

Flag: android.app.pic_uses_shared_memory
Bug: 360897450
Test: atest
 * FrameworksCoreTests:PropertyInvalidatedCacheTests
 * FrameworksCoreTests:IpcDataCacheTest
 * CtsOsTestCases:IpcDataCacheTest
 * CtsAppOpsTestCases
 * CtsMediaAudioTestCases
 * CtsVirtualDevicesAudioTestCases
Change-Id: I0250beac5b8e1d85c1a2ff21de8408f07f074a45

core/java/android/app/PropertyInvalidatedCache.java

diff --git a/core/java/android/app/PropertyInvalidatedCache.java b/core/java/android/app/PropertyInvalidatedCache.java
index 26bfec3..a39cf84 100644
--- a/core/java/android/app/PropertyInvalidatedCache.java
+++ b/core/java/android/app/PropertyInvalidatedCache.java
@@ -811,10 +811,20 @@
         return false; // Always disable shared memory on Ravenwood. (for now)
     }
 
+    /**
+     * Keys that cannot be put in shared memory yet.
+     */
+    private static boolean inSharedMemoryDenyList(@NonNull String name) {
+        final String pkginfo = PREFIX_SYSTEM + "package_info";
+        return name.equals(pkginfo);
+    };
+
     // Return true if this cache can use shared memory for its nonce.  Shared memory may be used
     // if the module is the system.
     private static boolean sharedMemoryOkay(@NonNull String name) {
-        return sSharedMemoryAvailable && name.startsWith(PREFIX_SYSTEM);
+        return sSharedMemoryAvailable
+                && name.startsWith(PREFIX_SYSTEM)
+                && !inSharedMemoryDenyList(name);
     }
 
     /**

core/java/android/app/performance.aconfig

diff --git a/core/java/android/app/performance.aconfig b/core/java/android/app/performance.aconfig
index 7484a85..f51f748 100644
--- a/core/java/android/app/performance.aconfig
+++ b/core/java/android/app/performance.aconfig
@@ -7,7 +7,7 @@
      is_exported: true
      is_fixed_read_only: true
      description: "PropertyInvalidatedCache uses shared memory for nonces."
-     bug: "366552454"
+     bug: "360897450"
 }
 
 flag {
@@ -16,5 +16,5 @@
      is_exported: true
      is_fixed_read_only: true
      description: "Enforce PropertyInvalidatedCache.setTestMode() protocol"
-     bug: "366552454"
+     bug: "360897450"
 }