// SPDX-License-Identifier: GPL-2.0 /* * Runtime test cases for CONFIG_FORTIFY_SOURCE that aren't expected to * Oops the kernel on success. (For those, see drivers/misc/lkdtm/fortify.c) * * For corner cases with UBSAN, try testing with: * * ./tools/testing/kunit/kunit.py run --arch=x86_64 \ * --kconfig_add CONFIG_FORTIFY_SOURCE=y \ * --kconfig_add CONFIG_UBSAN=y \ * --kconfig_add CONFIG_UBSAN_TRAP=y \ * --kconfig_add CONFIG_UBSAN_BOUNDS=y \ * --kconfig_add CONFIG_UBSAN_LOCAL_BOUNDS=y \ * --make_options LLVM=1 fortify */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include #include #include static const char array_of_10[] = "this is 10"; static const char *ptr_of_11 = "this is 11!"; static char array_unknown[] = "compiler thinks I might change"; static void known_sizes_test(struct kunit *test) { KUNIT_EXPECT_EQ(test, __compiletime_strlen("88888888"), 8); KUNIT_EXPECT_EQ(test, __compiletime_strlen(array_of_10), 10); KUNIT_EXPECT_EQ(test, __compiletime_strlen(ptr_of_11), 11); KUNIT_EXPECT_EQ(test, __compiletime_strlen(array_unknown), SIZE_MAX); /* Externally defined and dynamically sized string pointer: */ KUNIT_EXPECT_EQ(test, __compiletime_strlen(test->name), SIZE_MAX); } /* This is volatile so the optimizer can't perform DCE below. */ static volatile int pick; /* Not inline to keep optimizer from figuring out which string we want. */ static noinline size_t want_minus_one(int pick) { const char *str; switch (pick) { case 1: str = "4444"; break; case 2: str = "333"; break; default: str = "1"; break; } return __compiletime_strlen(str); } static void control_flow_split_test(struct kunit *test) { KUNIT_EXPECT_EQ(test, want_minus_one(pick), SIZE_MAX); } #define KUNIT_EXPECT_BOS(test, p, expected, name) \ KUNIT_EXPECT_EQ_MSG(test, __builtin_object_size(p, 1), \ expected, \ "__alloc_size() not working with __bos on " name "\n") #if !__has_builtin(__builtin_dynamic_object_size) #define KUNIT_EXPECT_BDOS(test, p, expected, name) \ /* Silence "unused variable 'expected'" warning. */ \ KUNIT_EXPECT_EQ(test, expected, expected) #else #define KUNIT_EXPECT_BDOS(test, p, expected, name) \ KUNIT_EXPECT_EQ_MSG(test, __builtin_dynamic_object_size(p, 1), \ expected, \ "__alloc_size() not working with __bdos on " name "\n") #endif /* If the execpted size is a constant value, __bos can see it. */ #define check_const(_expected, alloc, free) do { \ size_t expected = (_expected); \ void *p = alloc; \ KUNIT_EXPECT_TRUE_MSG(test, p != NULL, #alloc " failed?!\n"); \ KUNIT_EXPECT_BOS(test, p, expected, #alloc); \ KUNIT_EXPECT_BDOS(test, p, expected, #alloc); \ free; \ } while (0) /* If the execpted size is NOT a constant value, __bos CANNOT see it. */ #define check_dynamic(_expected, alloc, free) do { \ size_t expected = (_expected); \ void *p = alloc; \ KUNIT_EXPECT_TRUE_MSG(test, p != NULL, #alloc " failed?!\n"); \ KUNIT_EXPECT_BOS(test, p, SIZE_MAX, #alloc); \ KUNIT_EXPECT_BDOS(test, p, expected, #alloc); \ free; \ } while (0) /* Assortment of constant-value kinda-edge cases. */ #define CONST_TEST_BODY(TEST_alloc) do { \ /* Special-case vmalloc()-family to skip 0-sized allocs. */ \ if (strcmp(#TEST_alloc, "TEST_vmalloc") != 0) \ TEST_alloc(check_const, 0, 0); \ TEST_alloc(check_const, 1, 1); \ TEST_alloc(check_const, 128, 128); \ TEST_alloc(check_const, 1023, 1023); \ TEST_alloc(check_const, 1025, 1025); \ TEST_alloc(check_const, 4096, 4096); \ TEST_alloc(check_const, 4097, 4097); \ } while (0) static volatile size_t zero_size; static volatile size_t unknown_size = 50; #if !__has_builtin(__builtin_dynamic_object_size) #define DYNAMIC_TEST_BODY(TEST_alloc) \ kunit_skip(test, "Compiler is missing __builtin_dynamic_object_size() support\n") #else #define DYNAMIC_TEST_BODY(TEST_alloc) do { \ size_t size = unknown_size; \ \ /* \ * Expected size is "size" in each test, before it is then \ * internally incremented in each test. Requires we disable \ * -Wunsequenced. \ */ \ TEST_alloc(check_dynamic, size, size++); \ /* Make sure incrementing actually happened. */ \ KUNIT_EXPECT_NE(test, size, unknown_size); \ } while (0) #endif #define DEFINE_ALLOC_SIZE_TEST_PAIR(allocator) \ static void alloc_size_##allocator##_const_test(struct kunit *test) \ { \ CONST_TEST_BODY(TEST_##allocator); \ } \ static void alloc_size_##allocator##_dynamic_test(struct kunit *test) \ { \ DYNAMIC_TEST_BODY(TEST_##allocator); \ } #define TEST_kmalloc(checker, expected_size, alloc_size) do { \ gfp_t gfp = GFP_KERNEL | __GFP_NOWARN; \ void *orig; \ size_t len; \ \ checker(expected_size, kmalloc(alloc_size, gfp), \ kfree(p)); \ checker(expected_size, \ kmalloc_node(alloc_size, gfp, NUMA_NO_NODE), \ kfree(p)); \ checker(expected_size, kzalloc(alloc_size, gfp), \ kfree(p)); \ checker(expected_size, \ kzalloc_node(alloc_size, gfp, NUMA_NO_NODE), \ kfree(p)); \ checker(expected_size, kcalloc(1, alloc_size, gfp), \ kfree(p)); \ checker(expected_size, kcalloc(alloc_size, 1, gfp), \ kfree(p)); \ checker(expected_size, \ kcalloc_node(1, alloc_size, gfp, NUMA_NO_NODE), \ kfree(p)); \ checker(expected_size, \ kcalloc_node(alloc_size, 1, gfp, NUMA_NO_NODE), \ kfree(p)); \ checker(expected_size, kmalloc_array(1, alloc_size, gfp), \ kfree(p)); \ checker(expected_size, kmalloc_array(alloc_size, 1, gfp), \ kfree(p)); \ checker(expected_size, \ kmalloc_array_node(1, alloc_size, gfp, NUMA_NO_NODE), \ kfree(p)); \ checker(expected_size, \ kmalloc_array_node(alloc_size, 1, gfp, NUMA_NO_NODE), \ kfree(p)); \ checker(expected_size, __kmalloc(alloc_size, gfp), \ kfree(p)); \ checker(expected_size, \ __kmalloc_node(alloc_size, gfp, NUMA_NO_NODE), \ kfree(p)); \ \ orig = kmalloc(alloc_size, gfp); \ KUNIT_EXPECT_TRUE(test, orig != NULL); \ checker((expected_size) * 2, \ krealloc(orig, (alloc_size) * 2, gfp), \ kfree(p)); \ orig = kmalloc(alloc_size, gfp); \ KUNIT_EXPECT_TRUE(test, orig != NULL); \ checker((expected_size) * 2, \ krealloc_array(orig, 1, (alloc_size) * 2, gfp), \ kfree(p)); \ orig = kmalloc(alloc_size, gfp); \ KUNIT_EXPECT_TRUE(test, orig != NULL); \ checker((expected_size) * 2, \ krealloc_array(orig, (alloc_size) * 2, 1, gfp), \ kfree(p)); \ \ len = 11; \ /* Using memdup() with fixed size, so force unknown length. */ \ if (!__builtin_constant_p(expected_size)) \ len += zero_size; \ checker(len, kmemdup("hello there", len, gfp), kfree(p)); \ } while (0) DEFINE_ALLOC_SIZE_TEST_PAIR(kmalloc) /* Sizes are in pages, not bytes. */ #define TEST_vmalloc(checker, expected_pages, alloc_pages) do { \ gfp_t gfp = GFP_KERNEL | __GFP_NOWARN; \ checker((expected_pages) * PAGE_SIZE, \ vmalloc((alloc_pages) * PAGE_SIZE), vfree(p)); \ checker((expected_pages) * PAGE_SIZE, \ vzalloc((alloc_pages) * PAGE_SIZE), vfree(p)); \ checker((expected_pages) * PAGE_SIZE, \ __vmalloc((alloc_pages) * PAGE_SIZE, gfp), vfree(p)); \ } while (0) DEFINE_ALLOC_SIZE_TEST_PAIR(vmalloc) /* Sizes are in pages (and open-coded for side-effects), not bytes. */ #define TEST_kvmalloc(checker, expected_pages, alloc_pages) do { \ gfp_t gfp = GFP_KERNEL | __GFP_NOWARN; \ size_t prev_size; \ void *orig; \ \ checker((expected_pages) * PAGE_SIZE, \ kvmalloc((alloc_pages) * PAGE_SIZE, gfp), \ vfree(p)); \ checker((expected_pages) * PAGE_SIZE, \ kvmalloc_node((alloc_pages) * PAGE_SIZE, gfp, NUMA_NO_NODE), \ vfree(p)); \ checker((expected_pages) * PAGE_SIZE, \ kvzalloc((alloc_pages) * PAGE_SIZE, gfp), \ vfree(p)); \ checker((expected_pages) * PAGE_SIZE, \ kvzalloc_node((alloc_pages) * PAGE_SIZE, gfp, NUMA_NO_NODE), \ vfree(p)); \ checker((expected_pages) * PAGE_SIZE, \ kvcalloc(1, (alloc_pages) * PAGE_SIZE, gfp), \ vfree(p)); \ checker((expected_pages) * PAGE_SIZE, \ kvcalloc((alloc_pages) * PAGE_SIZE, 1, gfp), \ vfree(p)); \ checker((expected_pages) * PAGE_SIZE, \ kvmalloc_array(1, (alloc_pages) * PAGE_SIZE, gfp), \ vfree(p)); \ checker((expected_pages) * PAGE_SIZE, \ kvmalloc_array((alloc_pages) * PAGE_SIZE, 1, gfp), \ vfree(p)); \ \ prev_size = (expected_pages) * PAGE_SIZE; \ orig = kvmalloc(prev_size, gfp); \ KUNIT_EXPECT_TRUE(test, orig != NULL); \ checker(((expected_pages) * PAGE_SIZE) * 2, \ kvrealloc(orig, prev_size, \ ((alloc_pages) * PAGE_SIZE) * 2, gfp), \ kvfree(p)); \ } while (0) DEFINE_ALLOC_SIZE_TEST_PAIR(kvmalloc) #define TEST_devm_kmalloc(checker, expected_size, alloc_size) do { \ gfp_t gfp = GFP_KERNEL | __GFP_NOWARN; \ const char dev_name[] = "fortify-test"; \ struct device *dev; \ void *orig; \ size_t len; \ \ /* Create dummy device for devm_kmalloc()-family tests. */ \ dev = kunit_device_register(test, dev_name); \ KUNIT_ASSERT_FALSE_MSG(test, IS_ERR(dev), \ "Cannot register test device\n"); \ \ checker(expected_size, devm_kmalloc(dev, alloc_size, gfp), \ devm_kfree(dev, p)); \ checker(expected_size, devm_kzalloc(dev, alloc_size, gfp), \ devm_kfree(dev, p)); \ checker(expected_size, \ devm_kmalloc_array(dev, 1, alloc_size, gfp), \ devm_kfree(dev, p)); \ checker(expected_size, \ devm_kmalloc_array(dev, alloc_size, 1, gfp), \ devm_kfree(dev, p)); \ checker(expected_size, \ devm_kcalloc(dev, 1, alloc_size, gfp), \ devm_kfree(dev, p)); \ checker(expected_size, \ devm_kcalloc(dev, alloc_size, 1, gfp), \ devm_kfree(dev, p)); \ \ orig = devm_kmalloc(dev, alloc_size, gfp); \ KUNIT_EXPECT_TRUE(test, orig != NULL); \ checker((expected_size) * 2, \ devm_krealloc(dev, orig, (alloc_size) * 2, gfp), \ devm_kfree(dev, p)); \ \ len = 4; \ /* Using memdup() with fixed size, so force unknown length. */ \ if (!__builtin_constant_p(expected_size)) \ len += zero_size; \ checker(len, devm_kmemdup(dev, "Ohai", len, gfp), \ devm_kfree(dev, p)); \ \ kunit_device_unregister(test, dev); \ } while (0) DEFINE_ALLOC_SIZE_TEST_PAIR(devm_kmalloc) static struct kunit_case fortify_test_cases[] = { KUNIT_CASE(known_sizes_test), KUNIT_CASE(control_flow_split_test), KUNIT_CASE(alloc_size_kmalloc_const_test), KUNIT_CASE(alloc_size_kmalloc_dynamic_test), KUNIT_CASE(alloc_size_vmalloc_const_test), KUNIT_CASE(alloc_size_vmalloc_dynamic_test), KUNIT_CASE(alloc_size_kvmalloc_const_test), KUNIT_CASE(alloc_size_kvmalloc_dynamic_test), KUNIT_CASE(alloc_size_devm_kmalloc_const_test), KUNIT_CASE(alloc_size_devm_kmalloc_dynamic_test), {} }; static struct kunit_suite fortify_test_suite = { .name = "fortify", .test_cases = fortify_test_cases, }; kunit_test_suite(fortify_test_suite); MODULE_LICENSE("GPL");