commit 96cfebcf7e15b9aae665df7a06309ba2d9a2c430
author Peiyong Lin <lpy@google.com> Wed May 15 11:36:13 2019 -0700
committer Peiyong Lin <lpy@google.com> Wed May 15 11:36:13 2019 -0700
tree 1e5fb54e3a603ed5f64715d105835418353ba5ec
parent 3f8312b5dc975c391f85f90a4a0586ac3c7ac899

[SurfaceFlinger] Allow root to capture screen.

If adb is running in root, then uid is AID_ROOT and capture screen will fail.
This patch allows root to capture screen.

BUG: 132777517
Test: adb shell screencap -d 0 -p /sdcard/test.png produces a valid screenshot
Change-Id: Ib6eaad2dffa7a68f4b1fce548814f0c2f172c3fd

services/surfaceflinger/SurfaceFlinger.cpp

diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 4d885fb..3d71267 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -5100,7 +5100,7 @@
         case CAPTURE_SCREEN_BY_ID: {
             IPCThreadState* ipc = IPCThreadState::self();
             const int uid = ipc->getCallingUid();
-            if ((uid == AID_GRAPHICS) || (uid == AID_SYSTEM) || (uid == AID_SHELL)) {
+            if (uid == AID_ROOT || uid == AID_GRAPHICS || uid == AID_SYSTEM || uid == AID_SHELL) {
                 return OK;
             }
             return PERMISSION_DENIED;