Dont call ToolProps on drivers without supportsdk-1.2.198.0

The loader recently added support for calling into drivers in
vkGetPhysicalDeviceToolPropertieesEXT. However, it only used the value of
the function pointer to determine if it was safe. It was found that Mesa
drivers will return a non-null function pointer, even though they do not
support the extension, and so the loader called this function pointer which
would then segfault.

The loader prevents this by first checking if the extension is supported by
the physical device. This necessitates calling
vkEnumerateDeviceExtensionProperties and allocating some memory on each call
but since the number of times this function is called should be low, it is
not an undue performance burden. In the future, the loader should cache the
list of extensions when calling vkEnumeratePhysicalDevices so that checking if
a extension function is supported is fast and easy.

2 files changed, 61 insertions, 6 deletions

diff --git a/loader/extension_manual.c b/loader/extension_manual.c
index 415b64b74..65c573d91 100644
--- a/loader/extension_manual.c
+++ b/loader/extension_manual.c
@@ -305,11 +305,49 @@ VKAPI_ATTR VkResult VKAPI_CALL terminator_GetPhysicalDeviceToolPropertiesEXT(VkP
     struct loader_physical_device_term *phys_dev_term = (struct loader_physical_device_term *)physicalDevice;
     struct loader_icd_term *icd_term = phys_dev_term->this_icd_term;
 
-    if (icd_term->dispatch.GetPhysicalDeviceToolPropertiesEXT) {
-        return icd_term->dispatch.GetPhysicalDeviceToolPropertiesEXT(phys_dev_term->phys_dev, pToolCount, pToolProperties);
+    bool tooling_info_supported = false;
+    uint32_t ext_count = 0;
+    VkExtensionProperties *ext_props = NULL;
+    VkResult res = VK_SUCCESS;
+    VkResult enumerate_res = VK_SUCCESS;
+
+    enumerate_res = icd_term->dispatch.EnumerateDeviceExtensionProperties(phys_dev_term->phys_dev, NULL, &ext_count, NULL);
+    if (enumerate_res != VK_SUCCESS) {
+        goto out;
     }
 
+    ext_props = loader_instance_heap_alloc(icd_term->this_instance, sizeof(VkExtensionProperties) * ext_count,
+                                           VK_SYSTEM_ALLOCATION_SCOPE_COMMAND);
+    if (!ext_props) {
+        res = VK_ERROR_OUT_OF_HOST_MEMORY;
+        goto out;
+    }
+
+    enumerate_res = icd_term->dispatch.EnumerateDeviceExtensionProperties(phys_dev_term->phys_dev, NULL, &ext_count, ext_props);
+    if (enumerate_res != VK_SUCCESS) {
+        goto out;
+    }
+
+    for (uint32_t i = 0; i < ext_count; i++) {
+        if (strncmp(ext_props[i].extensionName, VK_EXT_TOOLING_INFO_EXTENSION_NAME, VK_MAX_EXTENSION_NAME_SIZE) == 0) {
+            tooling_info_supported = true;
+            break;
+        }
+    }
+
+    if (tooling_info_supported && icd_term->dispatch.GetPhysicalDeviceToolPropertiesEXT) {
+        res = icd_term->dispatch.GetPhysicalDeviceToolPropertiesEXT(phys_dev_term->phys_dev, pToolCount, pToolProperties);
+    }
+
+out:
     // In the case the driver didn't support the extension, make sure that the first layer doesn't find the count uninitialized
-    *pToolCount = 0;
-    return VK_SUCCESS;
+    if (!tooling_info_supported || !icd_term->dispatch.GetPhysicalDeviceToolPropertiesEXT) {
+        *pToolCount = 0;
+    }
+
+    if (ext_props) {
+        loader_instance_heap_free(icd_term->this_instance, ext_props);
+    }
+
+    return res;
 }
diff --git a/tests/loader_regression_tests.cpp b/tests/loader_regression_tests.cpp
index d1687a4f5..469aa8925 100644
--- a/tests/loader_regression_tests.cpp
+++ b/tests/loader_regression_tests.cpp
@@ -849,7 +849,24 @@ TEST(ExtensionManual, ToolingProperties) {
                                                      VK_TOOL_PURPOSE_VALIDATION_BIT_EXT,
                                                      "This tool does not exist",
                                                      "No-Layer"};
-    {  // extension
+    {  // No support in driver
+        SingleICDShim env{TestICDDetails{TEST_ICD_PATH_VERSION_6}};
+        env.get_test_icd().physical_devices.push_back({});
+
+        InstWrapper inst{env.vulkan_functions};
+        inst.CheckCreate();
+
+        auto phys_dev = inst.GetPhysDev();
+
+        auto getToolProperties = reinterpret_cast<PFN_vkGetPhysicalDeviceToolPropertiesEXT>(
+            inst.functions->vkGetInstanceProcAddr(inst, "vkGetPhysicalDeviceToolPropertiesEXT"));
+        handle_assert_has_value(getToolProperties);
+
+        uint32_t tool_count = 0;
+        ASSERT_EQ(VK_SUCCESS, getToolProperties(phys_dev, &tool_count, nullptr));
+        ASSERT_EQ(tool_count, 0);
+    }
+    {  // extension is supported in driver
         SingleICDShim env{TestICDDetails{TEST_ICD_PATH_VERSION_6}};
         env.get_test_icd().physical_devices.push_back({});
         env.get_test_icd().supports_tooling_info_ext = true;
@@ -864,7 +881,7 @@ TEST(ExtensionManual, ToolingProperties) {
         auto getToolProperties = reinterpret_cast<PFN_vkGetPhysicalDeviceToolPropertiesEXT>(
             inst.functions->vkGetInstanceProcAddr(inst, "vkGetPhysicalDeviceToolPropertiesEXT"));
         handle_assert_has_value(getToolProperties);
-        uint32_t tool_count = 1;
+        uint32_t tool_count = 0;
         ASSERT_EQ(VK_SUCCESS, getToolProperties(phys_dev, &tool_count, nullptr));
         ASSERT_EQ(tool_count, 1);
         VkPhysicalDeviceToolPropertiesEXT props{};