Mitigate the security vulnerability by sanitizing the transaction flags.

- This is part of fix of commit
  Id9d9012d4ede9c8330f0ce1096bcb78e51b7c5df for backporting.

Bug: 248031255
Test: test using displaytoken app manually on the phone, test shell
screenrecord during using displaytoken; atest
android.hardware.camera2.cts.FastBasicsTest

Change-Id: Id9d9012d4ede9c8330f0ce1096bcb78e51b7c5df
Merged-In: Id9d9012d4ede9c8330f0ce1096bcb78e51b7c5df

5 files changed, 27 insertions, 4 deletions

diff --git a/libs/gui/LayerState.cpp b/libs/gui/LayerState.cpp
index 502031c8d8..74e6ae6a9b 100644
--- a/libs/gui/LayerState.cpp
+++ b/libs/gui/LayerState.cpp
@@ -353,6 +353,27 @@ void DisplayState::merge(const DisplayState& other) {
     }
 }
 
+void DisplayState::sanitize(int32_t permissions) {
+    if (what & DisplayState::eLayerStackChanged) {
+        if (!(permissions & layer_state_t::Permission::ACCESS_SURFACE_FLINGER)) {
+            what &= ~DisplayState::eLayerStackChanged;
+            ALOGE("Stripped attempt to set eLayerStackChanged in sanitize");
+        }
+    }
+    if (what & DisplayState::eDisplayProjectionChanged) {
+        if (!(permissions & layer_state_t::Permission::ACCESS_SURFACE_FLINGER)) {
+            what &= ~DisplayState::eDisplayProjectionChanged;
+            ALOGE("Stripped attempt to set eDisplayProjectionChanged in sanitize");
+        }
+    }
+    if (what & DisplayState::eSurfaceChanged) {
+        if (!(permissions & layer_state_t::Permission::ACCESS_SURFACE_FLINGER)) {
+            what &= ~DisplayState::eSurfaceChanged;
+            ALOGE("Stripped attempt to set eSurfaceChanged in sanitize");
+        }
+    }
+}
+
 void layer_state_t::sanitize(int32_t permissions) {
     // TODO: b/109894387
     //
diff --git a/libs/gui/include/gui/LayerState.h b/libs/gui/include/gui/LayerState.h
index 0a9b75a7f1..0071d48227 100644
--- a/libs/gui/include/gui/LayerState.h
+++ b/libs/gui/include/gui/LayerState.h
@@ -320,6 +320,7 @@ struct DisplayState {
 
     DisplayState();
     void merge(const DisplayState& other);
+    void sanitize(int32_t permissions);
 
     uint32_t what = 0;
     uint32_t flags = 0;
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 6a17cd8881..b6fe16e624 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -4167,7 +4167,7 @@ status_t SurfaceFlinger::setTransactionState(
 
 bool SurfaceFlinger::applyTransactionState(const FrameTimelineInfo& frameTimelineInfo,
                                            Vector<ComposerState>& states,
-                                           const Vector<DisplayState>& displays, uint32_t flags,
+                                           Vector<DisplayState>& displays, uint32_t flags,
                                            const InputWindowCommands& inputWindowCommands,
                                            const int64_t desiredPresentTime, bool isAutoTimestamp,
                                            const client_cache_t& uncacheBuffer,
@@ -4176,7 +4176,8 @@ bool SurfaceFlinger::applyTransactionState(const FrameTimelineInfo& frameTimelin
                                            const std::vector<ListenerCallbacks>& listenerCallbacks,
                                            int originPid, int originUid, uint64_t transactionId) {
     uint32_t transactionFlags = 0;
-    for (const DisplayState& display : displays) {
+    for (DisplayState& display : displays) {
+        display.sanitize(permissions);
         transactionFlags |= setDisplayStateLocked(display);
     }
 
diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index f14c755c2b..dcf3be86b8 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -760,7 +760,7 @@ private:
      * Transactions
      */
     bool applyTransactionState(const FrameTimelineInfo& info, Vector<ComposerState>& state,
-                               const Vector<DisplayState>& displays, uint32_t flags,
+                               Vector<DisplayState>& displays, uint32_t flags,
                                const InputWindowCommands& inputWindowCommands,
                                const int64_t desiredPresentTime, bool isAutoTimestamp,
                                const client_cache_t& uncacheBuffer, const int64_t postTime,
diff --git a/services/surfaceflinger/tests/DisplayConfigs_test.cpp b/services/surfaceflinger/tests/DisplayConfigs_test.cpp
index 2dc96b8511..c58fe4831c 100644
--- a/services/surfaceflinger/tests/DisplayConfigs_test.cpp
+++ b/services/surfaceflinger/tests/DisplayConfigs_test.cpp
@@ -149,4 +149,4 @@ TEST_F(RefreshRateRangeTest, setAllowGroupSwitching) {
 } // namespace android
 
 // TODO(b/129481165): remove the #pragma below and fix conversion issues
-#pragma clang diagnostic pop // ignored "-Wextra"
\ No newline at end of file
+#pragma clang diagnostic pop // ignored "-Wextra"