commit 27fbcc77f3bc48845f726842a02cbc19f88b9f52
author Ady Abraham <adyabr@google.com> Mon Sep 20 14:54:57 2021 -0700
committer Ady Abraham <adyabr@google.com> Tue Sep 21 20:50:09 2021 +0000
tree 49193527d6ad1c6e1578a63d0555d58658a34358
parent 9b2f0cf92b889ada401c4e1aa70f5b9ae5b4c29d

SF: protect mDisplayCapabilities with a lock

There is a rare race condition where mDisplayCapabilities can be
read while it is getting updated, which causes a crash.

Bug: 196059993
Test: SF unit tests
Change-Id: Iaca9f1b61cdc1a59639a93f62c1716acddf8186b

services/surfaceflinger/DisplayHardware/HWComposer.cpp

diff --git a/services/surfaceflinger/DisplayHardware/HWComposer.cpp b/services/surfaceflinger/DisplayHardware/HWComposer.cpp
index 256bca9..c63ba0e 100644
--- a/services/surfaceflinger/DisplayHardware/HWComposer.cpp
+++ b/services/surfaceflinger/DisplayHardware/HWComposer.cpp
@@ -183,7 +183,7 @@
 bool HWComposer::hasDisplayCapability(HalDisplayId displayId,
                                       hal::DisplayCapability capability) const {
     RETURN_IF_INVALID_DISPLAY(displayId, false);
-    return mDisplayData.at(displayId).hwcDisplay->getCapabilities().count(capability) > 0;
+    return mDisplayData.at(displayId).hwcDisplay->hasCapability(capability);
 }
 
 std::optional<DisplayIdentificationInfo> HWComposer::onHotplug(hal::HWDisplayId hwcDisplayId,