From 3e88857d92eb32f2c862652bbf8603d97f3789b0 Mon Sep 17 00:00:00 2001
From: Tzarial <zork@google.com>
Date: Thu, 16 Jul 2026 15:04:47 +0000
Subject: [PATCH] Cap GLES debug marker length

Cap the marker length in Context::pushGroupMarker and
Context::insertEventMarker via GetMarkerLength to
maxDebugMessageLength (1024) to prevent driver and validation layer
issues when handling large labels, and avoid unbounded buffer growth
in backends.

Bug: b/524435922
Test: angle_end2end_tests --gtest_filter=DebugMarkerTest.*
Test: angle_deqp_gles2_tests --gtest_filter=*debug_marker*
Change-Id: I910971a589f49ab9dc7611c1a0e27aab7789ea64
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/8108817
Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Commit-Queue: Tzarial <zork@chromium.org>
---
diff --git a/src/libANGLE/Context.cpp b/src/libANGLE/Context.cpp
index acd6b60..ac1243e 100644
--- a/src/libANGLE/Context.cpp
+++ b/src/libANGLE/Context.cpp
@@ -424,14 +424,16 @@
     }
 }
 
-GLsizei GetMarkerLength(GLsizei length, const char *marker)
+GLsizei GetMarkerLength(GLsizei length, const char *marker, GLsizei maxLength)
 {
     if (length == 0)
     {
-        return static_cast<GLsizei>(
+        length = static_cast<GLsizei>(
             std::min<size_t>(strlen(marker), std::numeric_limits<GLsizei>::max()));
     }
-    return length;
+    // https://crbug.com/524435922: Cap debug marker length to prevent driver or validation layer
+    // issues with large labels.
+    return std::min(length, maxLength);
 }
 
 enum SubjectIndexes : angle::SubjectIndex
@@ -3222,7 +3224,9 @@
     }
 
     // If <length> is 0 then <marker> is assumed to be null-terminated.
-    ANGLE_CONTEXT_TRY(mImplementation->insertEventMarker(GetMarkerLength(length, marker), marker));
+    ANGLE_CONTEXT_TRY(mImplementation->insertEventMarker(
+        GetMarkerLength(length, marker, static_cast<GLsizei>(getCaps().maxDebugMessageLength)),
+        marker));
 }
 
 void Context::pushGroupMarker(GLsizei length, const char *marker)
@@ -3241,8 +3245,9 @@
     else
     {
         // If <length> is 0 then <marker> is assumed to be null-terminated.
-        ANGLE_CONTEXT_TRY(
-            mImplementation->pushGroupMarker(GetMarkerLength(length, marker), marker));
+        ANGLE_CONTEXT_TRY(mImplementation->pushGroupMarker(
+            GetMarkerLength(length, marker, static_cast<GLsizei>(getCaps().maxDebugMessageLength)),
+            marker));
     }
     mState.incrementGroupMarkers();
 }
diff --git a/src/tests/gl_tests/DebugMarkerTest.cpp b/src/tests/gl_tests/DebugMarkerTest.cpp
index e23a370..d8054c5 100644
--- a/src/tests/gl_tests/DebugMarkerTest.cpp
+++ b/src/tests/gl_tests/DebugMarkerTest.cpp
@@ -147,6 +147,30 @@
     ASSERT_GL_NO_ERROR();
 }
 
+// Test that passing an oversized marker to EXT_debug_marker entry points does not crash.
+TEST_P(DebugMarkerTest, OversizedMarkerNoCrash)
+{
+    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_EXT_debug_marker"));
+
+    // Create a string larger than 16KB (default page size for PoolAllocator in CBH)
+    std::string largeMarker(32 * 1024, 'a');
+
+    glPushGroupMarkerEXT(static_cast<GLsizei>(largeMarker.length()), largeMarker.c_str());
+
+    GLenum error = glGetError();
+    if (error == GL_NO_ERROR)
+    {
+        glPopGroupMarkerEXT();
+    }
+    else
+    {
+        EXPECT_EQ(static_cast<GLenum>(GL_INVALID_VALUE), error);
+    }
+
+    glInsertEventMarkerEXT(static_cast<GLsizei>(largeMarker.length()), largeMarker.c_str());
+    ASSERT_GL_NO_ERROR();
+}
+
 // Use this to select which configurations (e.g. which renderer, which GLES major version) these
 // tests should be run against.
 ANGLE_INSTANTIATE_TEST_ES2(DebugMarkerTest);

diff --git a/src/tests/gl_tests/DebugMarkerTest.cpp b/src/tests/gl_tests/DebugMarkerTest.cpp
index e23a370..d8054c5 100644
--- a/src/tests/gl_tests/DebugMarkerTest.cpp
+++ b/src/tests/gl_tests/DebugMarkerTest.cpp
@@ -147,6 +147,30 @@
     ASSERT_GL_NO_ERROR();
 }
 
+// Test that passing an oversized marker to EXT_debug_marker entry points does not crash.
+TEST_P(DebugMarkerTest, OversizedMarkerNoCrash)
+{
+    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_EXT_debug_marker"));
+
+    // Create a string larger than 16KB (default page size for PoolAllocator in CBH)
+    std::string largeMarker(32 * 1024, 'a');
+
+    glPushGroupMarkerEXT(static_cast<GLsizei>(largeMarker.length()), largeMarker.c_str());
+
+    GLenum error = glGetError();
+    if (error == GL_NO_ERROR)
+    {
+        glPopGroupMarkerEXT();
+    }
+    else
+    {
+        EXPECT_EQ(static_cast<GLenum>(GL_INVALID_VALUE), error);
+    }
+
+    glInsertEventMarkerEXT(static_cast<GLsizei>(largeMarker.length()), largeMarker.c_str());
+    ASSERT_GL_NO_ERROR();
+}
+
 // Use this to select which configurations (e.g. which renderer, which GLES major version) these
 // tests should be run against.
 ANGLE_INSTANTIATE_TEST_ES2(DebugMarkerTest);