take loader_lock in terminator_DestroySurfaceKHR

loader/wsi.c

@@ -337,6 +337,10 @@ VKAPI_ATTR void VKAPI_CALL terminator_DestroySurfaceKHR(VkInstance instance, VkS
             return;
         }
 #endif  // VK_USE_PLATFORM_MACOS_MVK
+        // Every surface creation terminator holds loader_lock while it reserves a slot in loader_inst->surfaces_list and
+        // grows each driver's surface_list, either of which can reallocate the list. vkDestroySurfaceKHR only requires
+        // the surface itself to be externally synchronized, so take the same lock before touching that shared state.
+        loader_platform_thread_lock_mutex(&loader_lock);
         for (struct loader_icd_term *icd_term = loader_inst->icd_terms; icd_term != NULL; icd_term = icd_term->next) {
             if (icd_term->enabled_instance_extensions.khr_surface &&
                 icd_term->scanned_icd->interface_version >= ICD_VER_SUPPORTS_ICD_SURFACE_KHR &&
@@ -360,6 +364,7 @@ VKAPI_ATTR void VKAPI_CALL terminator_DestroySurfaceKHR(VkInstance instance, VkS
             loader_instance_heap_free(loader_inst, icd_surface->create_info);
         }
         loader_release_object_from_list(&loader_inst->surfaces_list, icd_surface->surface_index);
+        loader_platform_thread_unlock_mutex(&loader_lock);
         // NOLINTNEXTLINE(performance-no-int-to-ptr) - decoding the loader-internal pointer out of the handle
         loader_instance_heap_free(loader_inst, (void *)(uintptr_t)surface);
     }

tests/loader_threading_tests.cpp

@@ -172,3 +172,30 @@ TEST(Threading, SetDebugUtilsNameCreateDestroyLoop) {
         set_debug_name_threads[i].join();
     }
 }
+
+void create_destroy_surface_loop(FrameworkEnvironment* env, uint32_t num_loops, InstWrapper* inst) {
+    for (uint32_t i = 0; i < num_loops; i++) {
+        VkSurfaceKHR surface{};
+        ASSERT_EQ(VK_SUCCESS, create_surface(*inst, surface));
+        env->vulkan_functions.vkDestroySurfaceKHR(inst->inst, surface, nullptr);
+    }
+}
+
+TEST(Threading, SurfaceCreateDestroyLoop) {
+    const auto processor_count = std::thread::hardware_concurrency();
+    uint32_t num_loops = 100;
+    FrameworkEnvironment env{FrameworkSettings{}.set_log_filter("")};
+    env.add_icd(TEST_ICD_PATH_VERSION_2).setup_WSI().add_physical_device({});
+
+    InstWrapper inst{env.vulkan_functions};
+    inst.create_info.setup_WSI();
+    inst.CheckCreate();
+
+    std::vector<std::thread> surface_threads;
+    for (uint32_t i = 0; i < processor_count; i++) {
+        surface_threads.emplace_back(create_destroy_surface_loop, &env, num_loops, &inst);
+    }
+    for (uint32_t i = 0; i < processor_count; i++) {
+        surface_threads[i].join();
+    }
+}