Snap for 8417617 from f2d5b2a2da277d3f4dbcb81a8e3d71d76457740a to mainline-tethering-release

Change-Id: I38318adea25d078264623957e219e4fc40aec5be
diff --git a/libs/gui/LayerState.cpp b/libs/gui/LayerState.cpp
index 2f31fbb..bb4b446 100644
--- a/libs/gui/LayerState.cpp
+++ b/libs/gui/LayerState.cpp
@@ -381,6 +381,71 @@
     }
 }
 
+void layer_state_t::sanitize(int32_t permissions) {
+    // TODO: b/109894387
+    //
+    // SurfaceFlinger's renderer is not prepared to handle cropping in the face of arbitrary
+    // rotation. To see the problem observe that if we have a square parent, and a child
+    // of the same size, then we rotate the child 45 degrees around its center, the child
+    // must now be cropped to a non rectangular 8 sided region.
+    //
+    // Of course we can fix this in the future. For now, we are lucky, SurfaceControl is
+    // private API, and arbitrary rotation is used in limited use cases, for instance:
+    // - WindowManager only uses rotation in one case, which is on a top level layer in which
+    //   cropping is not an issue.
+    // - Launcher, as a privileged app, uses this to transition an application to PiP
+    //   (picture-in-picture) mode.
+    //
+    // However given that abuse of rotation matrices could lead to surfaces extending outside
+    // of cropped areas, we need to prevent non-root clients without permission
+    // ACCESS_SURFACE_FLINGER nor ROTATE_SURFACE_FLINGER
+    // (a.k.a. everyone except WindowManager / tests / Launcher) from setting non rectangle
+    // preserving transformations.
+    if (what & eMatrixChanged) {
+        if (!(permissions & Permission::ROTATE_SURFACE_FLINGER)) {
+            ui::Transform t;
+            t.set(matrix.dsdx, matrix.dtdy, matrix.dtdx, matrix.dsdy);
+            if (!t.preserveRects()) {
+                what &= ~eMatrixChanged;
+                ALOGE("Stripped non rect preserving matrix in sanitize");
+            }
+        }
+    }
+
+    if (what & layer_state_t::eInputInfoChanged) {
+        if (!(permissions & Permission::ACCESS_SURFACE_FLINGER)) {
+            what &= ~eInputInfoChanged;
+            ALOGE("Stripped attempt to set eInputInfoChanged in sanitize");
+        }
+    }
+    if (what & layer_state_t::eTrustedOverlayChanged) {
+        if (!(permissions & Permission::ACCESS_SURFACE_FLINGER)) {
+            what &= ~eTrustedOverlayChanged;
+            ALOGE("Stripped attempt to set eTrustedOverlay in sanitize");
+        }
+    }
+    if (what & layer_state_t::eDropInputModeChanged) {
+        if (!(permissions & Permission::ACCESS_SURFACE_FLINGER)) {
+            what &= ~eDropInputModeChanged;
+            ALOGE("Stripped attempt to set eDropInputModeChanged in sanitize");
+        }
+    }
+    if (what & layer_state_t::eFrameRateSelectionPriority) {
+        if (!(permissions & Permission::ACCESS_SURFACE_FLINGER)) {
+            what &= ~eFrameRateSelectionPriority;
+            ALOGE("Stripped attempt to set eFrameRateSelectionPriority in sanitize");
+        }
+    }
+    if (what & layer_state_t::eFrameRateChanged) {
+        if (!ValidateFrameRate(frameRate, frameRateCompatibility,
+                               changeFrameRateStrategy,
+                               "layer_state_t::sanitize",
+                               permissions & Permission::ACCESS_SURFACE_FLINGER)) {
+            what &= ~eFrameRateChanged; // logged in ValidateFrameRate
+        }
+    }
+}
+
 void layer_state_t::merge(const layer_state_t& other) {
     if (other.what & ePositionChanged) {
         what |= ePositionChanged;
diff --git a/libs/gui/SurfaceComposerClient.cpp b/libs/gui/SurfaceComposerClient.cpp
index 6ffd25d..3f1277e 100644
--- a/libs/gui/SurfaceComposerClient.cpp
+++ b/libs/gui/SurfaceComposerClient.cpp
@@ -527,6 +527,13 @@
     mListenerCallbacks = other.mListenerCallbacks;
 }
 
+void SurfaceComposerClient::Transaction::sanitize() {
+    for (auto & [handle, composerState] : mComposerStates) {
+        composerState.state.sanitize(0 /* permissionMask */);
+    }
+    mInputWindowCommands.clear();
+}
+
 std::unique_ptr<SurfaceComposerClient::Transaction>
 SurfaceComposerClient::Transaction::createFromParcel(const Parcel* parcel) {
     auto transaction = std::make_unique<Transaction>();
@@ -611,7 +618,6 @@
         if (composerState.read(*parcel) == BAD_VALUE) {
             return BAD_VALUE;
         }
-
         composerStates[surfaceControlHandle] = composerState;
     }
 
diff --git a/libs/gui/include/gui/LayerState.h b/libs/gui/include/gui/LayerState.h
index feef343..9460319 100644
--- a/libs/gui/include/gui/LayerState.h
+++ b/libs/gui/include/gui/LayerState.h
@@ -63,6 +63,12 @@
  * Used to communicate layer information between SurfaceFlinger and its clients.
  */
 struct layer_state_t {
+    enum Permission {
+        ACCESS_SURFACE_FLINGER = 0x1,
+        ROTATE_SURFACE_FLINGER = 0x2,
+        INTERNAL_SYSTEM_WINDOW = 0x4,
+    };
+
     enum {
         eLayerHidden = 0x01,         // SURFACE_HIDDEN in SurfaceControl.java
         eLayerOpaque = 0x02,         // SURFACE_OPAQUE
@@ -130,6 +136,7 @@
     status_t read(const Parcel& input);
     bool hasBufferChanges() const;
     bool hasValidBuffer() const;
+    void sanitize(int32_t permissions);
 
     struct matrix22_t {
         float dsdx{0};
diff --git a/libs/gui/include/gui/SurfaceComposerClient.h b/libs/gui/include/gui/SurfaceComposerClient.h
index 6e17212..4b20750 100644
--- a/libs/gui/include/gui/SurfaceComposerClient.h
+++ b/libs/gui/include/gui/SurfaceComposerClient.h
@@ -587,6 +587,14 @@
         void setAnimationTransaction();
         void setEarlyWakeupStart();
         void setEarlyWakeupEnd();
+
+        /**
+         * Strip the transaction of all permissioned requests, required when
+         * accepting transactions across process boundaries.
+         *
+         * TODO (b/213644870): Remove all permissioned things from Transaction
+         */
+        void sanitize();
     };
 
     status_t clearLayerFrameStats(const sp<IBinder>& token) const;