From a5f58a31268da95e36c0918ac75589c05e81b892 Mon Sep 17 00:00:00 2001
From: Ikalco <73481042+ikalco@users.noreply.github.com>
Date: Tue, 23 Jul 2024 13:03:15 -0500
Subject: [PATCH] layer-shell: validate exclusiveEdge and don't set it as top
 by default (#7006)

* validate exclusiveEdge and don't set it as top by default

* make sure exclusive edge anchor is within bounds
---
 src/protocols/LayerShell.cpp | 12 ++++++++++--
 src/protocols/LayerShell.hpp |  2 +-
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/src/protocols/LayerShell.cpp b/src/protocols/LayerShell.cpp
index 029f261d..4e733b35 100644
--- a/src/protocols/LayerShell.cpp
+++ b/src/protocols/LayerShell.cpp
@@ -11,7 +11,7 @@ void CLayerShellResource::SState::reset() {
     exclusive     = 0;
     interactivity = ZWLR_LAYER_SURFACE_V1_KEYBOARD_INTERACTIVITY_NONE;
     layer         = ZWLR_LAYER_SHELL_V1_LAYER_BOTTOM;
-    exclusiveEdge = ZWLR_LAYER_SURFACE_V1_ANCHOR_TOP;
+    exclusiveEdge = (zwlrLayerSurfaceV1Anchor)0;
     desiredSize   = {};
     margin        = {0, 0, 0, 0};
 }
@@ -152,7 +152,15 @@ CLayerShellResource::CLayerShellResource(SP<CZwlrLayerSurfaceV1> resource_, SP<C
     });
 
     resource->setSetExclusiveEdge([this](CZwlrLayerSurfaceV1* r, zwlrLayerSurfaceV1Anchor anchor) {
-        // TODO: validate anchor
+        if (anchor > (ZWLR_LAYER_SURFACE_V1_ANCHOR_TOP | ZWLR_LAYER_SURFACE_V1_ANCHOR_BOTTOM | ZWLR_LAYER_SURFACE_V1_ANCHOR_LEFT | ZWLR_LAYER_SURFACE_V1_ANCHOR_RIGHT)) {
+            r->error(ZWLR_LAYER_SURFACE_V1_ERROR_INVALID_EXCLUSIVE_EDGE, "Invalid exclusive edge");
+            return;
+        }
+
+        if (!pending.anchor || !(pending.anchor & anchor)) {
+            r->error(ZWLR_LAYER_SURFACE_V1_ERROR_INVALID_EXCLUSIVE_EDGE, "Exclusive edge doesn't align with anchor");
+            return;
+        }
 
         pending.committed |= STATE_EDGE;
         pending.exclusiveEdge = anchor;
diff --git a/src/protocols/LayerShell.hpp b/src/protocols/LayerShell.hpp
index 6d29248a..221d95c0 100644
--- a/src/protocols/LayerShell.hpp
+++ b/src/protocols/LayerShell.hpp
@@ -47,7 +47,7 @@ class CLayerShellResource : public ISurfaceRole {
         Vector2D                                desiredSize;
         zwlrLayerSurfaceV1KeyboardInteractivity interactivity = ZWLR_LAYER_SURFACE_V1_KEYBOARD_INTERACTIVITY_NONE;
         zwlrLayerShellV1Layer                   layer         = ZWLR_LAYER_SHELL_V1_LAYER_BOTTOM;
-        zwlrLayerSurfaceV1Anchor                exclusiveEdge = ZWLR_LAYER_SURFACE_V1_ANCHOR_TOP;
+        zwlrLayerSurfaceV1Anchor                exclusiveEdge = (zwlrLayerSurfaceV1Anchor)0;
         uint32_t                                committed     = 0;
 
         struct {