Merge "Fix lock inversion in PackageInstaller." into lmp-dev (37ccf18b) · Commits · e / os / android_frameworks_base

services/core/java/com/android/server/pm/PackageInstallerService.java

+19 −8

Original line number	Diff line number	Diff line
		@@ -144,6 +144,7 @@ public class PackageInstallerService extends IPackageInstaller.Stub {

		private final File mStagingDir;
		private final HandlerThread mInstallThread;
		private final Handler mInstallHandler;

		private final Callbacks mCallbacks;

		@@ -188,6 +189,8 @@ public class PackageInstallerService extends IPackageInstaller.Stub {
		mInstallThread = new HandlerThread(TAG);
		mInstallThread.start();

		mInstallHandler = new Handler(mInstallThread.getLooper());

		mCallbacks = new Callbacks(mInstallThread.getLooper());

		mSessionsFile = new AtomicFile(
		@@ -961,13 +964,19 @@ public class PackageInstallerService extends IPackageInstaller.Stub {
		mCallbacks.notifySessionProgressChanged(session.sessionId, session.userId, progress);
		}

		public void onSessionFinished(PackageInstallerSession session, boolean success) {
		public void onSessionFinished(final PackageInstallerSession session, boolean success) {
		mCallbacks.notifySessionFinished(session.sessionId, session.userId, success);

		mInstallHandler.post(new Runnable() {
		@Override
		public void run() {
		synchronized (mSessions) {
		mSessions.remove(session.sessionId);
		mHistoricalSessions.put(session.sessionId, session);
		writeSessionsLocked();
		}
		writeSessionsAsync();
		}
		});
		}

		public void onSessionPrepared(PackageInstallerSession session) {
		@@ -976,11 +985,13 @@ public class PackageInstallerService extends IPackageInstaller.Stub {
		writeSessionsAsync();
		}

		public void onSessionSealed(PackageInstallerSession session) {
		public void onSessionSealedBlocking(PackageInstallerSession session) {
		// It's very important that we block until we've recorded the
		// session as being sealed, since we never want to allow mutation
		// after sealing.
		synchronized (mSessions) {
		writeSessionsLocked();
		}
		}
		}
		}

services/core/java/com/android/server/pm/PackageInstallerSession.java

+12 −7

Original line number	Diff line number	Diff line
		@@ -410,7 +410,9 @@ public class PackageInstallerSession extends IPackageInstallerSession.Stub {
		public void commit(IntentSender statusReceiver) {
		Preconditions.checkNotNull(statusReceiver);

		final boolean wasSealed;
		synchronized (mLock) {
		wasSealed = mSealed;
		if (!mSealed) {
		// Verify that all writers are hands-off
		for (FileBridge bridge : mBridges) {
		@@ -418,17 +420,20 @@ public class PackageInstallerSession extends IPackageInstallerSession.Stub {
		throw new SecurityException("Files still open");
		}
		}

		// Persist the fact that we've sealed ourselves to prevent
		// mutations of any hard links we create.
		mSealed = true;
		mCallback.onSessionSealed(this);
		}
		}

		// Client staging is fully done at this point
		mClientProgress = 1f;
		computeProgressLocked(true);
		}

		if (!wasSealed) {
		// Persist the fact that we've sealed ourselves to prevent
		// mutations of any hard links we create. We do this without holding
		// the session lock, since otherwise it's a lock inversion.
		mCallback.onSessionSealedBlocking(this);
		}

		// This ongoing commit should keep session active, even though client
		// will probably close their end.