|  | // 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 <kunit/test.h> | 
|  | #include <linux/device.h> | 
|  | #include <linux/slab.h> | 
|  | #include <linux/string.h> | 
|  | #include <linux/vmalloc.h> | 
|  |  | 
|  | 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 = root_device_register(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));					\ | 
|  | \ | 
|  | device_unregister(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"); |