Re: [RFC PATCH v2 3/3] KASAN: Port KASAN Tests to KUnit

From: Patricia Alfonso
Date: Tue Mar 24 2020 - 13:52:31 EST


On Tue, Mar 24, 2020 at 9:48 AM Alan Maguire <alan.maguire@xxxxxxxxxx> wrote:
>
> On Thu, 19 Mar 2020, Patricia Alfonso wrote:
>
> > Transfer all previous tests for KASAN to KUnit so they can be run
> > more easily. Using kunit_tool, developers can run these tests with their
> > other KUnit tests and see "pass" or "fail" with the appropriate KASAN
> > report instead of needing to parse each KASAN report to test KASAN
> > functionalities. All KASAN reports are still printed to dmesg.
> >
> > Stack tests do not work in UML so those tests are protected inside an
> > "#if IS_ENABLED(CONFIG_KASAN_STACK)" so this only runs if stack
> > instrumentation is enabled.
> >
> > copy_user_test cannot be run in KUnit so there is a separate test file
> > for those tests, which can be run as before as a module.
> >
> > Signed-off-by: Patricia Alfonso <trishalfonso@xxxxxxxxxx>
> > ---
> > lib/Kconfig.kasan | 13 +-
> > lib/Makefile | 1 +
> > lib/test_kasan.c | 606 ++++++++++++++-----------------------
> > lib/test_kasan_copy_user.c | 75 +++++
> > 4 files changed, 309 insertions(+), 386 deletions(-)
> > create mode 100644 lib/test_kasan_copy_user.c
> >
> > diff --git a/lib/Kconfig.kasan b/lib/Kconfig.kasan
> > index 5b54f3c9a741..f026c2e62b1d 100644
> > --- a/lib/Kconfig.kasan
> > +++ b/lib/Kconfig.kasan
> > @@ -159,9 +159,16 @@ config KASAN_VMALLOC
> > stacks), but at the cost of higher memory usage.
> >
> > config TEST_KASAN
> > - tristate "Module for testing KASAN for bug detection"
> > - depends on m && KASAN
> > + tristate "KUnit testing KASAN for bug detection"
> > + depends on KASAN && KUNIT=y
>
> could just be depends on KASAN && KUNIT I think.
>
This depends on KUNIT=y because KASAN is built-in and therefore cannot
use code from KUnit if it is built as a module.

> > help
> > - This is a test module doing various nasty things like
> > + This is a test suite doing various nasty things like
> > out of bounds accesses, use after free. It is useful for testing
> > kernel debugging features like KASAN.
> > +
> > +config TEST_KASAN_USER
> > + tristate "Module testing KASAN for bug detection on copy user tests"
> > + depends on m && KASAN
> > + help
> > + This is a test module for copy_user_tests because these functions
> > + cannot be tested by KUnit so they must be their own module.
> > diff --git a/lib/Makefile b/lib/Makefile
> > index 5d64890d6b6a..e0dc4430e405 100644
> > --- a/lib/Makefile
> > +++ b/lib/Makefile
> > @@ -62,6 +62,7 @@ obj-$(CONFIG_TEST_IDA) += test_ida.o
> > obj-$(CONFIG_TEST_KASAN) += test_kasan.o
> > CFLAGS_test_kasan.o += -fno-builtin
> > CFLAGS_test_kasan.o += $(call cc-disable-warning, vla)
> > +obj-$(CONFIG_TEST_KASAN_USER) += test_kasan_copy_user.o
> > obj-$(CONFIG_TEST_UBSAN) += test_ubsan.o
> > CFLAGS_test_ubsan.o += $(call cc-disable-warning, vla)
> > UBSAN_SANITIZE_test_ubsan.o := y
> > diff --git a/lib/test_kasan.c b/lib/test_kasan.c
> > index cf73c6bee81b..c255495e6ce3 100644
> > --- a/lib/test_kasan.c
> > +++ b/lib/test_kasan.c
> > @@ -5,8 +5,6 @@
> > * Author: Andrey Ryabinin <a.ryabinin@xxxxxxxxxxx>
> > */
> >
> > -#define pr_fmt(fmt) "kasan test: %s " fmt, __func__
> > -
> > #include <linux/bitops.h>
> > #include <linux/delay.h>
> > #include <linux/kasan.h>
> > @@ -25,8 +23,26 @@
> >
> > #include <kunit/test.h>
> >
> > +#if IS_BUILTIN(CONFIG_KUNIT)
>
> fix here to be IS_ENABLED(CONFIG_KUNIT)
>
Same comment as above. This relies on KUnit being built-in.

> > +
> > struct kunit_resource resource;
> > struct kunit_kasan_expectation fail_data;
> > +bool multishot;
> > +
> > +int kasan_multi_shot_init(struct kunit *test)
> > +{
> > + /*
> > + * Temporarily enable multi-shot mode. Otherwise, we'd only get a
> > + * report for the first case.
> > + */
> > + multishot = kasan_save_enable_multi_shot();
> > + return 0;
> > +}
> > +
> > +void kasan_multi_shot_exit(struct kunit *test)
> > +{
> > + kasan_restore_multi_shot(multishot);
> > +}
> >
> > #define KUNIT_SET_KASAN_DATA(test) do { \
> > fail_data.report_expected = true; \
> > @@ -60,61 +76,44 @@ struct kunit_kasan_expectation fail_data;
> > KUNIT_DO_EXPECT_KASAN_FAIL(test, condition); \
> > } while (0)
> >
> > -/*
> > - * Note: test functions are marked noinline so that their names appear in
> > - * reports.
> > - */
> > -
> > -static noinline void __init kmalloc_oob_right(void)
> > +static void kmalloc_oob_right(struct kunit *test)
> > {
> > char *ptr;
> > size_t size = 123;
> >
> > - pr_info("out-of-bounds to right\n");
> > ptr = kmalloc(size, GFP_KERNEL);
> > - if (!ptr) {
> > - pr_err("Allocation failed\n");
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
> >
> > - ptr[size] = 'x';
> > + KUNIT_EXPECT_KASAN_FAIL(test, ptr[size] = 'x');
> > kfree(ptr);
> > }
> >
> > -static noinline void __init kmalloc_oob_left(void)
> > +static void kmalloc_oob_left(struct kunit *test)
> > {
> > char *ptr;
> > size_t size = 15;
> >
> > - pr_info("out-of-bounds to left\n");
> > ptr = kmalloc(size, GFP_KERNEL);
> > - if (!ptr) {
> > - pr_err("Allocation failed\n");
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
> >
> > - *ptr = *(ptr - 1);
> > + KUNIT_EXPECT_KASAN_FAIL(test, *ptr = *(ptr - 1));
> > kfree(ptr);
> > }
> >
> > -static noinline void __init kmalloc_node_oob_right(void)
> > +static void kmalloc_node_oob_right(struct kunit *test)
> > {
> > char *ptr;
> > size_t size = 4096;
> >
> > - pr_info("kmalloc_node(): out-of-bounds to right\n");
> > ptr = kmalloc_node(size, GFP_KERNEL, 0);
> > - if (!ptr) {
> > - pr_err("Allocation failed\n");
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
> >
> > - ptr[size] = 0;
> > + KUNIT_EXPECT_KASAN_FAIL(test, ptr[size] = 0);
> > kfree(ptr);
> > }
> >
> > #ifdef CONFIG_SLUB
> > -static noinline void __init kmalloc_pagealloc_oob_right(void)
> > +static void kmalloc_pagealloc_oob_right(struct kunit *test)
> > {
> > char *ptr;
> > size_t size = KMALLOC_MAX_CACHE_SIZE + 10;
> > @@ -122,324 +121,253 @@ static noinline void __init kmalloc_pagealloc_oob_right(void)
> > /* Allocate a chunk that does not fit into a SLUB cache to trigger
> > * the page allocator fallback.
> > */
> > - pr_info("kmalloc pagealloc allocation: out-of-bounds to right\n");
> > ptr = kmalloc(size, GFP_KERNEL);
> > - if (!ptr) {
> > - pr_err("Allocation failed\n");
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
> >
> > - ptr[size] = 0;
> > + KUNIT_EXPECT_KASAN_FAIL(test, ptr[size] = 0);
> > kfree(ptr);
> > }
> >
> > -static noinline void __init kmalloc_pagealloc_uaf(void)
> > +static void kmalloc_pagealloc_uaf(struct kunit *test)
> > {
> > char *ptr;
> > size_t size = KMALLOC_MAX_CACHE_SIZE + 10;
> >
> > - pr_info("kmalloc pagealloc allocation: use-after-free\n");
> > ptr = kmalloc(size, GFP_KERNEL);
> > - if (!ptr) {
> > - pr_err("Allocation failed\n");
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
> >
> > kfree(ptr);
> > - ptr[0] = 0;
> > + KUNIT_EXPECT_KASAN_FAIL(test, ptr[0] = 0);
> > }
> >
> > -static noinline void __init kmalloc_pagealloc_invalid_free(void)
> > +static void kmalloc_pagealloc_invalid_free(struct kunit *test)
> > {
> > char *ptr;
> > size_t size = KMALLOC_MAX_CACHE_SIZE + 10;
> >
> > - pr_info("kmalloc pagealloc allocation: invalid-free\n");
> > ptr = kmalloc(size, GFP_KERNEL);
> > - if (!ptr) {
> > - pr_err("Allocation failed\n");
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
> >
> > - kfree(ptr + 1);
> > + KUNIT_EXPECT_KASAN_FAIL(test, kfree(ptr + 1));
> > }
> > -#endif
> > +#endif /* CONFIG_SLUB */
> >
> > -static noinline void __init kmalloc_large_oob_right(void)
> > +static void kmalloc_large_oob_right(struct kunit *test)
> > {
> > char *ptr;
> > size_t size = KMALLOC_MAX_CACHE_SIZE - 256;
> > /* Allocate a chunk that is large enough, but still fits into a slab
> > * and does not trigger the page allocator fallback in SLUB.
> > */
> > - pr_info("kmalloc large allocation: out-of-bounds to right\n");
> > ptr = kmalloc(size, GFP_KERNEL);
> > - if (!ptr) {
> > - pr_err("Allocation failed\n");
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
> >
> > - ptr[size] = 0;
> > + KUNIT_EXPECT_KASAN_FAIL(test, ptr[size] = 0);
> > kfree(ptr);
> > }
> >
> > -static noinline void __init kmalloc_oob_krealloc_more(void)
> > +static void kmalloc_oob_krealloc_more(struct kunit *test)
> > {
> > char *ptr1, *ptr2;
> > size_t size1 = 17;
> > size_t size2 = 19;
> >
> > - pr_info("out-of-bounds after krealloc more\n");
> > ptr1 = kmalloc(size1, GFP_KERNEL);
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1);
> > +
> > ptr2 = krealloc(ptr1, size2, GFP_KERNEL);
> > - if (!ptr1 || !ptr2) {
> > - pr_err("Allocation failed\n");
> > - kfree(ptr1);
> > - kfree(ptr2);
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2);
> >
> > - ptr2[size2] = 'x';
> > + KUNIT_EXPECT_KASAN_FAIL(test, ptr2[size2] = 'x');
> > kfree(ptr2);
> > }
> >
> > -static noinline void __init kmalloc_oob_krealloc_less(void)
> > +static void kmalloc_oob_krealloc_less(struct kunit *test)
> > {
> > char *ptr1, *ptr2;
> > size_t size1 = 17;
> > size_t size2 = 15;
> >
> > - pr_info("out-of-bounds after krealloc less\n");
> > ptr1 = kmalloc(size1, GFP_KERNEL);
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1);
> > +
> > ptr2 = krealloc(ptr1, size2, GFP_KERNEL);
> > - if (!ptr1 || !ptr2) {
> > - pr_err("Allocation failed\n");
> > - kfree(ptr1);
> > - return;
> > - }
> > - ptr2[size2] = 'x';
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2);
> > +
> > + KUNIT_EXPECT_KASAN_FAIL(test, ptr2[size2] = 'x');
> > kfree(ptr2);
> > }
> >
> > -static noinline void __init kmalloc_oob_16(void)
> > +static void kmalloc_oob_16(struct kunit *test)
> > {
> > struct {
> > u64 words[2];
> > } *ptr1, *ptr2;
> >
> > - pr_info("kmalloc out-of-bounds for 16-bytes access\n");
> > ptr1 = kmalloc(sizeof(*ptr1) - 3, GFP_KERNEL);
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1);
> > +
> > ptr2 = kmalloc(sizeof(*ptr2), GFP_KERNEL);
> > - if (!ptr1 || !ptr2) {
> > - pr_err("Allocation failed\n");
> > - kfree(ptr1);
> > - kfree(ptr2);
> > - return;
> > - }
> > - *ptr1 = *ptr2;
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2);
> > +
> > + KUNIT_EXPECT_KASAN_FAIL(test, *ptr1 = *ptr2);
> > kfree(ptr1);
> > kfree(ptr2);
> > }
> >
> > -static noinline void __init kmalloc_oob_memset_2(void)
> > +static void kmalloc_oob_memset_2(struct kunit *test)
> > {
> > char *ptr;
> > size_t size = 8;
> >
> > - pr_info("out-of-bounds in memset2\n");
> > ptr = kmalloc(size, GFP_KERNEL);
> > - if (!ptr) {
> > - pr_err("Allocation failed\n");
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
> >
> > - memset(ptr+7, 0, 2);
> > + KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr+7, 0, 2));
> > kfree(ptr);
> > }
> >
> > -static noinline void __init kmalloc_oob_memset_4(void)
> > +static void kmalloc_oob_memset_4(struct kunit *test)
> > {
> > char *ptr;
> > size_t size = 8;
> >
> > - pr_info("out-of-bounds in memset4\n");
> > ptr = kmalloc(size, GFP_KERNEL);
> > - if (!ptr) {
> > - pr_err("Allocation failed\n");
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
> >
> > - memset(ptr+5, 0, 4);
> > + KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr+5, 0, 4));
> > kfree(ptr);
> > }
> >
> >
> > -static noinline void __init kmalloc_oob_memset_8(void)
> > +static void kmalloc_oob_memset_8(struct kunit *test)
> > {
> > char *ptr;
> > size_t size = 8;
> >
> > - pr_info("out-of-bounds in memset8\n");
> > ptr = kmalloc(size, GFP_KERNEL);
> > - if (!ptr) {
> > - pr_err("Allocation failed\n");
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
> >
> > - memset(ptr+1, 0, 8);
> > + KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr+1, 0, 8));
> > kfree(ptr);
> > }
> >
> > -static noinline void __init kmalloc_oob_memset_16(void)
> > +static void kmalloc_oob_memset_16(struct kunit *test)
> > {
> > char *ptr;
> > size_t size = 16;
> >
> > - pr_info("out-of-bounds in memset16\n");
> > ptr = kmalloc(size, GFP_KERNEL);
> > - if (!ptr) {
> > - pr_err("Allocation failed\n");
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
> >
> > - memset(ptr+1, 0, 16);
> > + KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr+1, 0, 16));
> > kfree(ptr);
> > }
> >
> > -static noinline void __init kmalloc_oob_in_memset(void)
> > +static void kmalloc_oob_in_memset(struct kunit *test)
> > {
> > char *ptr;
> > size_t size = 666;
> >
> > - pr_info("out-of-bounds in memset\n");
> > ptr = kmalloc(size, GFP_KERNEL);
> > - if (!ptr) {
> > - pr_err("Allocation failed\n");
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
> >
> > - memset(ptr, 0, size+5);
> > + KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr, 0, size+5));
> > kfree(ptr);
> > }
> >
> > -static noinline void __init kmalloc_uaf(void)
> > +static void kmalloc_uaf(struct kunit *test)
> > {
> > char *ptr;
> > size_t size = 10;
> >
> > - pr_info("use-after-free\n");
> > ptr = kmalloc(size, GFP_KERNEL);
> > - if (!ptr) {
> > - pr_err("Allocation failed\n");
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
> >
> > kfree(ptr);
> > - *(ptr + 8) = 'x';
> > + KUNIT_EXPECT_KASAN_FAIL(test, *(ptr + 8) = 'x');
> > }
> >
> > -static noinline void __init kmalloc_uaf_memset(void)
> > +static void kmalloc_uaf_memset(struct kunit *test)
> > {
> > char *ptr;
> > size_t size = 33;
> >
> > - pr_info("use-after-free in memset\n");
> > ptr = kmalloc(size, GFP_KERNEL);
> > - if (!ptr) {
> > - pr_err("Allocation failed\n");
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
> >
> > kfree(ptr);
> > - memset(ptr, 0, size);
> > + KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr, 0, size));
> > }
> >
> > -static noinline void __init kmalloc_uaf2(void)
> > +static void kmalloc_uaf2(struct kunit *test)
> > {
> > char *ptr1, *ptr2;
> > size_t size = 43;
> >
> > - pr_info("use-after-free after another kmalloc\n");
> > ptr1 = kmalloc(size, GFP_KERNEL);
> > - if (!ptr1) {
> > - pr_err("Allocation failed\n");
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1);
> >
> > kfree(ptr1);
> > +
> > ptr2 = kmalloc(size, GFP_KERNEL);
> > - if (!ptr2) {
> > - pr_err("Allocation failed\n");
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2);
> > +
> > + KUNIT_EXPECT_KASAN_FAIL(test, ptr1[40] = 'x');
> > + KUNIT_EXPECT_PTR_NE(test, ptr1, ptr2);
> >
> > - ptr1[40] = 'x';
> > - if (ptr1 == ptr2)
> > - pr_err("Could not detect use-after-free: ptr1 == ptr2\n");
> > kfree(ptr2);
> > }
> >
> > -static noinline void __init kfree_via_page(void)
> > +static void kfree_via_page(struct kunit *test)
> > {
> > char *ptr;
> > size_t size = 8;
> > struct page *page;
> > unsigned long offset;
> >
> > - pr_info("invalid-free false positive (via page)\n");
> > ptr = kmalloc(size, GFP_KERNEL);
> > - if (!ptr) {
> > - pr_err("Allocation failed\n");
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
> >
> > page = virt_to_page(ptr);
> > offset = offset_in_page(ptr);
> > kfree(page_address(page) + offset);
> > }
> >
> > -static noinline void __init kfree_via_phys(void)
> > +static void kfree_via_phys(struct kunit *test)
> > {
> > char *ptr;
> > size_t size = 8;
> > phys_addr_t phys;
> >
> > - pr_info("invalid-free false positive (via phys)\n");
> > ptr = kmalloc(size, GFP_KERNEL);
> > - if (!ptr) {
> > - pr_err("Allocation failed\n");
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
> >
> > phys = virt_to_phys(ptr);
> > kfree(phys_to_virt(phys));
> > }
> >
> > -static noinline void __init kmem_cache_oob(void)
> > +static void kmem_cache_oob(struct kunit *test)
> > {
> > char *p;
> > size_t size = 200;
> > struct kmem_cache *cache = kmem_cache_create("test_cache",
> > size, 0,
> > 0, NULL);
> > - if (!cache) {
> > - pr_err("Cache allocation failed\n");
> > - return;
> > - }
> > - pr_info("out-of-bounds in kmem_cache_alloc\n");
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache);
> > p = kmem_cache_alloc(cache, GFP_KERNEL);
> > if (!p) {
> > - pr_err("Allocation failed\n");
> > + kunit_err(test, "Allocation failed: %s\n", __func__);
> > kmem_cache_destroy(cache);
> > return;
> > }
> >
> > - *p = p[size];
> > + KUNIT_EXPECT_KASAN_FAIL(test, *p = p[size]);
> > kmem_cache_free(cache, p);
> > kmem_cache_destroy(cache);
> > }
> >
> > -static noinline void __init memcg_accounted_kmem_cache(void)
> > +static void memcg_accounted_kmem_cache(struct kunit *test)
> > {
> > int i;
> > char *p;
> > @@ -447,12 +375,8 @@ static noinline void __init memcg_accounted_kmem_cache(void)
> > struct kmem_cache *cache;
> >
> > cache = kmem_cache_create("test_cache", size, 0, SLAB_ACCOUNT, NULL);
> > - if (!cache) {
> > - pr_err("Cache allocation failed\n");
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache);
> >
> > - pr_info("allocate memcg accounted object\n");
> > /*
> > * Several allocations with a delay to allow for lazy per memcg kmem
> > * cache creation.
> > @@ -472,134 +396,80 @@ static noinline void __init memcg_accounted_kmem_cache(void)
> >
> > static char global_array[10];
> >
> > -static noinline void __init kasan_global_oob(void)
> > +static void kasan_global_oob(struct kunit *test)
> > {
> > volatile int i = 3;
> > char *p = &global_array[ARRAY_SIZE(global_array) + i];
> >
> > - pr_info("out-of-bounds global variable\n");
> > - *(volatile char *)p;
> > -}
> > -
> > -static noinline void __init kasan_stack_oob(void)
> > -{
> > - char stack_array[10];
> > - volatile int i = 0;
> > - char *p = &stack_array[ARRAY_SIZE(stack_array) + i];
> > -
> > - pr_info("out-of-bounds on stack\n");
> > - *(volatile char *)p;
> > + KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p);
> > }
> >
> > -static noinline void __init ksize_unpoisons_memory(void)
> > +static void ksize_unpoisons_memory(struct kunit *test)
> > {
> > char *ptr;
> > size_t size = 123, real_size;
> >
> > - pr_info("ksize() unpoisons the whole allocated chunk\n");
> > ptr = kmalloc(size, GFP_KERNEL);
> > - if (!ptr) {
> > - pr_err("Allocation failed\n");
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
> > real_size = ksize(ptr);
> > /* This access doesn't trigger an error. */
> > ptr[size] = 'x';
> > /* This one does. */
> > - ptr[real_size] = 'y';
> > + KUNIT_EXPECT_KASAN_FAIL(test, ptr[real_size] = 'y');
> > kfree(ptr);
> > }
> >
> > -static noinline void __init copy_user_test(void)
> > +#if (IS_ENABLED(CONFIG_KASAN_STACK))
> > +static void kasan_stack_oob(struct kunit *test)
> > {
> > - char *kmem;
> > - char __user *usermem;
> > - size_t size = 10;
> > - int unused;
> > -
> > - kmem = kmalloc(size, GFP_KERNEL);
> > - if (!kmem)
> > - return;
> > -
> > - usermem = (char __user *)vm_mmap(NULL, 0, PAGE_SIZE,
> > - PROT_READ | PROT_WRITE | PROT_EXEC,
> > - MAP_ANONYMOUS | MAP_PRIVATE, 0);
> > - if (IS_ERR(usermem)) {
> > - pr_err("Failed to allocate user memory\n");
> > - kfree(kmem);
> > - return;
> > - }
> > -
> > - pr_info("out-of-bounds in copy_from_user()\n");
> > - unused = copy_from_user(kmem, usermem, size + 1);
> > -
> > - pr_info("out-of-bounds in copy_to_user()\n");
> > - unused = copy_to_user(usermem, kmem, size + 1);
> > -
> > - pr_info("out-of-bounds in __copy_from_user()\n");
> > - unused = __copy_from_user(kmem, usermem, size + 1);
> > -
> > - pr_info("out-of-bounds in __copy_to_user()\n");
> > - unused = __copy_to_user(usermem, kmem, size + 1);
> > -
> > - pr_info("out-of-bounds in __copy_from_user_inatomic()\n");
> > - unused = __copy_from_user_inatomic(kmem, usermem, size + 1);
> > -
> > - pr_info("out-of-bounds in __copy_to_user_inatomic()\n");
> > - unused = __copy_to_user_inatomic(usermem, kmem, size + 1);
> > -
> > - pr_info("out-of-bounds in strncpy_from_user()\n");
> > - unused = strncpy_from_user(kmem, usermem, size + 1);
> > + char stack_array[10];
> > + volatile int i = 0;
> > + char *p = &stack_array[ARRAY_SIZE(stack_array) + i];
> >
> > - vm_munmap((unsigned long)usermem, PAGE_SIZE);
> > - kfree(kmem);
> > + KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p);
> > }
> >
> > -static noinline void __init kasan_alloca_oob_left(void)
> > +static void kasan_alloca_oob_left(struct kunit *test)
> > {
> > volatile int i = 10;
> > char alloca_array[i];
> > char *p = alloca_array - 1;
> >
> > - pr_info("out-of-bounds to left on alloca\n");
> > - *(volatile char *)p;
> > + KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p);
> > }
> >
> > -static noinline void __init kasan_alloca_oob_right(void)
> > +static void kasan_alloca_oob_right(struct kunit *test)
> > {
> > volatile int i = 10;
> > char alloca_array[i];
> > char *p = alloca_array + i;
> >
> > - pr_info("out-of-bounds to right on alloca\n");
> > - *(volatile char *)p;
> > + KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p);
> > }
> > +#endif /* CONFIG_KASAN_STACK */
> >
> > -static noinline void __init kmem_cache_double_free(void)
> > +static void kmem_cache_double_free(struct kunit *test)
> > {
> > char *p;
> > size_t size = 200;
> > struct kmem_cache *cache;
> >
> > cache = kmem_cache_create("test_cache", size, 0, 0, NULL);
> > - if (!cache) {
> > - pr_err("Cache allocation failed\n");
> > - return;
> > - }
> > - pr_info("double-free on heap object\n");
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache);
> > +
> > p = kmem_cache_alloc(cache, GFP_KERNEL);
> > if (!p) {
> > - pr_err("Allocation failed\n");
> > + kunit_err(test, "Allocation failed: %s\n", __func__);
> > kmem_cache_destroy(cache);
> > return;
> > }
> >
> > kmem_cache_free(cache, p);
> > - kmem_cache_free(cache, p);
> > + KUNIT_EXPECT_KASAN_FAIL(test, kmem_cache_free(cache, p));
> > kmem_cache_destroy(cache);
> > }
> >
> > -static noinline void __init kmem_cache_invalid_free(void)
> > +static void kmem_cache_invalid_free(struct kunit *test)
> > {
> > char *p;
> > size_t size = 200;
> > @@ -607,20 +477,17 @@ static noinline void __init kmem_cache_invalid_free(void)
> >
> > cache = kmem_cache_create("test_cache", size, 0, SLAB_TYPESAFE_BY_RCU,
> > NULL);
> > - if (!cache) {
> > - pr_err("Cache allocation failed\n");
> > - return;
> > - }
> > - pr_info("invalid-free of heap object\n");
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache);
> > +
> > p = kmem_cache_alloc(cache, GFP_KERNEL);
> > if (!p) {
> > - pr_err("Allocation failed\n");
> > + kunit_err(test, "Allocation failed: %s\n", __func__);
> > kmem_cache_destroy(cache);
> > return;
> > }
> >
> > /* Trigger invalid free, the object doesn't get freed */
> > - kmem_cache_free(cache, p + 1);
> > + KUNIT_EXPECT_KASAN_FAIL(test, kmem_cache_free(cache, p + 1));
> >
> > /*
> > * Properly free the object to prevent the "Objects remaining in
> > @@ -631,45 +498,39 @@ static noinline void __init kmem_cache_invalid_free(void)
> > kmem_cache_destroy(cache);
> > }
> >
> > -static noinline void __init kasan_memchr(void)
> > +static void kasan_memchr(struct kunit *test)
> > {
> > char *ptr;
> > size_t size = 24;
> >
> > - pr_info("out-of-bounds in memchr\n");
> > ptr = kmalloc(size, GFP_KERNEL | __GFP_ZERO);
> > - if (!ptr)
> > - return;
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
> >
> > - memchr(ptr, '1', size + 1);
> > + KUNIT_EXPECT_KASAN_FAIL(test, memchr(ptr, '1', size + 1));
> > kfree(ptr);
> > }
> >
> > -static noinline void __init kasan_memcmp(void)
> > +static void kasan_memcmp(struct kunit *test)
> > {
> > char *ptr;
> > size_t size = 24;
> > int arr[9];
> >
> > - pr_info("out-of-bounds in memcmp\n");
> > ptr = kmalloc(size, GFP_KERNEL | __GFP_ZERO);
> > - if (!ptr)
> > - return;
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
> >
> > memset(arr, 0, sizeof(arr));
> > - memcmp(ptr, arr, size+1);
> > + KUNIT_EXPECT_KASAN_FAIL(test, memcmp(ptr, arr, size+1));
> > kfree(ptr);
> > }
> >
> > -static noinline void __init kasan_strings(void)
> > +static void kasan_strings(struct kunit *test)
> > {
> > char *ptr;
> > size_t size = 24;
> >
> > - pr_info("use-after-free in strchr\n");
> > ptr = kmalloc(size, GFP_KERNEL | __GFP_ZERO);
> > - if (!ptr)
> > - return;
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
> >
> > kfree(ptr);
> >
> > @@ -680,188 +541,167 @@ static noinline void __init kasan_strings(void)
> > * will likely point to zeroed byte.
> > */
> > ptr += 16;
> > - strchr(ptr, '1');
> > + KUNIT_EXPECT_KASAN_FAIL(test, strchr(ptr, '1'));
> >
> > - pr_info("use-after-free in strrchr\n");
> > - strrchr(ptr, '1');
> > + KUNIT_EXPECT_KASAN_FAIL(test, strrchr(ptr, '1'));
> >
> > - pr_info("use-after-free in strcmp\n");
> > - strcmp(ptr, "2");
> > + KUNIT_EXPECT_KASAN_FAIL(test, strcmp(ptr, "2"));
> >
> > - pr_info("use-after-free in strncmp\n");
> > - strncmp(ptr, "2", 1);
> > + KUNIT_EXPECT_KASAN_FAIL(test, strncmp(ptr, "2", 1));
> >
> > - pr_info("use-after-free in strlen\n");
> > - strlen(ptr);
> > + KUNIT_EXPECT_KASAN_FAIL(test, strlen(ptr));
> >
> > - pr_info("use-after-free in strnlen\n");
> > - strnlen(ptr, 1);
> > + KUNIT_EXPECT_KASAN_FAIL(test, strnlen(ptr, 1));
> > }
> >
> > -static noinline void __init kasan_bitops(void)
> > +static void kasan_bitops(struct kunit *test)
> > {
> > /*
> > * Allocate 1 more byte, which causes kzalloc to round up to 16-bytes;
> > * this way we do not actually corrupt other memory.
> > */
> > long *bits = kzalloc(sizeof(*bits) + 1, GFP_KERNEL);
> > - if (!bits)
> > - return;
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, bits);
> >
> > /*
> > * Below calls try to access bit within allocated memory; however, the
> > * below accesses are still out-of-bounds, since bitops are defined to
> > * operate on the whole long the bit is in.
> > */
> > - pr_info("out-of-bounds in set_bit\n");
> > - set_bit(BITS_PER_LONG, bits);
> > + KUNIT_EXPECT_KASAN_FAIL(test, set_bit(BITS_PER_LONG, bits));
> >
> > - pr_info("out-of-bounds in __set_bit\n");
> > - __set_bit(BITS_PER_LONG, bits);
> > + KUNIT_EXPECT_KASAN_FAIL(test, __set_bit(BITS_PER_LONG, bits));
> >
> > - pr_info("out-of-bounds in clear_bit\n");
> > - clear_bit(BITS_PER_LONG, bits);
> > + KUNIT_EXPECT_KASAN_FAIL(test, clear_bit(BITS_PER_LONG, bits));
> >
> > - pr_info("out-of-bounds in __clear_bit\n");
> > - __clear_bit(BITS_PER_LONG, bits);
> > + KUNIT_EXPECT_KASAN_FAIL(test, __clear_bit(BITS_PER_LONG, bits));
> >
> > - pr_info("out-of-bounds in clear_bit_unlock\n");
> > - clear_bit_unlock(BITS_PER_LONG, bits);
> > + KUNIT_EXPECT_KASAN_FAIL(test, clear_bit_unlock(BITS_PER_LONG, bits));
> >
> > - pr_info("out-of-bounds in __clear_bit_unlock\n");
> > - __clear_bit_unlock(BITS_PER_LONG, bits);
> > + KUNIT_EXPECT_KASAN_FAIL(test, __clear_bit_unlock(BITS_PER_LONG, bits));
> >
> > - pr_info("out-of-bounds in change_bit\n");
> > - change_bit(BITS_PER_LONG, bits);
> > + KUNIT_EXPECT_KASAN_FAIL(test, change_bit(BITS_PER_LONG, bits));
> >
> > - pr_info("out-of-bounds in __change_bit\n");
> > - __change_bit(BITS_PER_LONG, bits);
> > + KUNIT_EXPECT_KASAN_FAIL(test, __change_bit(BITS_PER_LONG, bits));
> >
> > /*
> > * Below calls try to access bit beyond allocated memory.
> > */
> > - pr_info("out-of-bounds in test_and_set_bit\n");
> > - test_and_set_bit(BITS_PER_LONG + BITS_PER_BYTE, bits);
> > + KUNIT_EXPECT_KASAN_FAIL(test,
> > + test_and_set_bit(BITS_PER_LONG + BITS_PER_BYTE, bits));
> >
> > - pr_info("out-of-bounds in __test_and_set_bit\n");
> > - __test_and_set_bit(BITS_PER_LONG + BITS_PER_BYTE, bits);
> > + KUNIT_EXPECT_KASAN_FAIL(test,
> > + __test_and_set_bit(BITS_PER_LONG + BITS_PER_BYTE, bits));
> >
> > - pr_info("out-of-bounds in test_and_set_bit_lock\n");
> > - test_and_set_bit_lock(BITS_PER_LONG + BITS_PER_BYTE, bits);
> > + KUNIT_EXPECT_KASAN_FAIL(test,
> > + test_and_set_bit_lock(BITS_PER_LONG + BITS_PER_BYTE, bits));
> >
> > - pr_info("out-of-bounds in test_and_clear_bit\n");
> > - test_and_clear_bit(BITS_PER_LONG + BITS_PER_BYTE, bits);
> > + KUNIT_EXPECT_KASAN_FAIL(test,
> > + test_and_clear_bit(BITS_PER_LONG + BITS_PER_BYTE, bits));
> >
> > - pr_info("out-of-bounds in __test_and_clear_bit\n");
> > - __test_and_clear_bit(BITS_PER_LONG + BITS_PER_BYTE, bits);
> > + KUNIT_EXPECT_KASAN_FAIL(test,
> > + __test_and_clear_bit(BITS_PER_LONG + BITS_PER_BYTE, bits));
> >
> > - pr_info("out-of-bounds in test_and_change_bit\n");
> > - test_and_change_bit(BITS_PER_LONG + BITS_PER_BYTE, bits);
> > + KUNIT_EXPECT_KASAN_FAIL(test,
> > + test_and_change_bit(BITS_PER_LONG + BITS_PER_BYTE, bits));
> >
> > - pr_info("out-of-bounds in __test_and_change_bit\n");
> > - __test_and_change_bit(BITS_PER_LONG + BITS_PER_BYTE, bits);
> > + KUNIT_EXPECT_KASAN_FAIL(test,
> > + __test_and_change_bit(BITS_PER_LONG + BITS_PER_BYTE, bits));
> >
> > - pr_info("out-of-bounds in test_bit\n");
> > - (void)test_bit(BITS_PER_LONG + BITS_PER_BYTE, bits);
> > + KUNIT_EXPECT_KASAN_FAIL(test,
> > + (void)test_bit(BITS_PER_LONG + BITS_PER_BYTE, bits));
> >
> > #if defined(clear_bit_unlock_is_negative_byte)
> > - pr_info("out-of-bounds in clear_bit_unlock_is_negative_byte\n");
> > - clear_bit_unlock_is_negative_byte(BITS_PER_LONG + BITS_PER_BYTE, bits);
> > + KUNIT_EXPECT_KASAN_FAIL(test,
> > + clear_bit_unlock_is_negative_byte(BITS_PER_LONG + BITS_PER_BYTE,
> > + bits));
> > #endif
> > kfree(bits);
> > }
> >
> > -static noinline void __init kmalloc_double_kzfree(void)
> > +static void kmalloc_double_kzfree(struct kunit *test)
> > {
> > char *ptr;
> > size_t size = 16;
> >
> > - pr_info("double-free (kzfree)\n");
> > ptr = kmalloc(size, GFP_KERNEL);
> > - if (!ptr) {
> > - pr_err("Allocation failed\n");
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
> >
> > kzfree(ptr);
> > - kzfree(ptr);
> > + KUNIT_EXPECT_KASAN_FAIL(test, kzfree(ptr));
> > }
> >
> > #ifdef CONFIG_KASAN_VMALLOC
> > -static noinline void __init vmalloc_oob(void)
> > +static void vmalloc_oob(struct kunit *test)
> > {
> > void *area;
> >
> > - pr_info("vmalloc out-of-bounds\n");
> > -
> > /*
> > * We have to be careful not to hit the guard page.
> > * The MMU will catch that and crash us.
> > */
> > area = vmalloc(3000);
> > - if (!area) {
> > - pr_err("Allocation failed\n");
> > - return;
> > - }
> > + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, area);
> >
> > - ((volatile char *)area)[3100];
> > + KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)area)[3100]);
> > vfree(area);
> > }
> > #else
> > -static void __init vmalloc_oob(void) {}
> > +static void vmalloc_oob(struct kunit *test) {}
> > #endif
> >
> > -static int __init kmalloc_tests_init(void)
> > -{
> > - /*
> > - * Temporarily enable multi-shot mode. Otherwise, we'd only get a
> > - * report for the first case.
> > - */
> > - bool multishot = kasan_save_enable_multi_shot();
> > -
> > - kmalloc_oob_right();
> > - kmalloc_oob_left();
> > - kmalloc_node_oob_right();
> > +static struct kunit_case kasan_kunit_test_cases[] = {
> > + KUNIT_CASE(kmalloc_oob_right),
> > + KUNIT_CASE(kmalloc_oob_left),
> > + KUNIT_CASE(kmalloc_node_oob_right),
> > #ifdef CONFIG_SLUB
> > - kmalloc_pagealloc_oob_right();
> > - kmalloc_pagealloc_uaf();
> > - kmalloc_pagealloc_invalid_free();
> > -#endif
> > - kmalloc_large_oob_right();
> > - kmalloc_oob_krealloc_more();
> > - kmalloc_oob_krealloc_less();
> > - kmalloc_oob_16();
> > - kmalloc_oob_in_memset();
> > - kmalloc_oob_memset_2();
> > - kmalloc_oob_memset_4();
> > - kmalloc_oob_memset_8();
> > - kmalloc_oob_memset_16();
> > - kmalloc_uaf();
> > - kmalloc_uaf_memset();
> > - kmalloc_uaf2();
> > - kfree_via_page();
> > - kfree_via_phys();
> > - kmem_cache_oob();
> > - memcg_accounted_kmem_cache();
> > - kasan_stack_oob();
> > - kasan_global_oob();
> > - kasan_alloca_oob_left();
> > - kasan_alloca_oob_right();
> > - ksize_unpoisons_memory();
> > - copy_user_test();
> > - kmem_cache_double_free();
> > - kmem_cache_invalid_free();
> > - kasan_memchr();
> > - kasan_memcmp();
> > - kasan_strings();
> > - kasan_bitops();
> > - kmalloc_double_kzfree();
> > - vmalloc_oob();
> > -
> > - kasan_restore_multi_shot(multishot);
> > -
> > - return -EAGAIN;
> > -}
> > + KUNIT_CASE(kmalloc_pagealloc_oob_right),
> > + KUNIT_CASE(kmalloc_pagealloc_uaf),
> > + KUNIT_CASE(kmalloc_pagealloc_invalid_free),
> > +#endif /* CONFIG_SLUB */
> > + KUNIT_CASE(kmalloc_large_oob_right),
> > + KUNIT_CASE(kmalloc_oob_krealloc_more),
> > + KUNIT_CASE(kmalloc_oob_krealloc_less),
> > + KUNIT_CASE(kmalloc_oob_16),
> > + KUNIT_CASE(kmalloc_oob_in_memset),
> > + KUNIT_CASE(kmalloc_oob_memset_2),
> > + KUNIT_CASE(kmalloc_oob_memset_4),
> > + KUNIT_CASE(kmalloc_oob_memset_8),
> > + KUNIT_CASE(kmalloc_oob_memset_16),
> > + KUNIT_CASE(kmalloc_uaf),
> > + KUNIT_CASE(kmalloc_uaf_memset),
> > + KUNIT_CASE(kmalloc_uaf2),
> > + KUNIT_CASE(kfree_via_page),
> > + KUNIT_CASE(kfree_via_phys),
> > + KUNIT_CASE(kmem_cache_oob),
> > + KUNIT_CASE(memcg_accounted_kmem_cache),
> > + KUNIT_CASE(kasan_global_oob),
> > +#if (IS_ENABLED(CONFIG_KASAN_STACK))
> > + KUNIT_CASE(kasan_stack_oob), // need stack protection
> > + KUNIT_CASE(kasan_alloca_oob_left),
> > + KUNIT_CASE(kasan_alloca_oob_right),
> > +#endif /*CONFIG_KASAN_STACK*/
> > + KUNIT_CASE(ksize_unpoisons_memory),
> > + KUNIT_CASE(kmem_cache_double_free),
> > + KUNIT_CASE(kmem_cache_invalid_free),
> > + KUNIT_CASE(kasan_memchr),
> > + KUNIT_CASE(kasan_memcmp),
> > + KUNIT_CASE(kasan_strings),
> > + KUNIT_CASE(kasan_bitops),
> > + KUNIT_CASE(kmalloc_double_kzfree),
> > + KUNIT_CASE(vmalloc_oob),
> > + {}
> > +};
> > +
> > +static struct kunit_suite kasan_kunit_test_suite = {
> > + .name = "kasan_kunit_test",
> > + .init = kasan_multi_shot_init,
> > + .test_cases = kasan_kunit_test_cases,
> > + .exit = kasan_multi_shot_exit,
> > +};
> > +
> > +kunit_test_suite(kasan_kunit_test_suite);
> > +
> > +#endif /* BUILTIN(CONFIG_KUNIT) */
> >
> > -module_init(kmalloc_tests_init);
> > MODULE_LICENSE("GPL");
> > diff --git a/lib/test_kasan_copy_user.c b/lib/test_kasan_copy_user.c
> > new file mode 100644
> > index 000000000000..9523cbc332ec
> > --- /dev/null
> > +++ b/lib/test_kasan_copy_user.c
> > @@ -0,0 +1,75 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + *
> > + * Copyright (c) 2014 Samsung Electronics Co., Ltd.
> > + * Author: Andrey Ryabinin <a.ryabinin@xxxxxxxxxxx>
> > + */
> > +
> > +#define pr_fmt(fmt) "kasan test: %s " fmt, __func__
> > +
> > +#include <linux/mman.h>
> > +#include <linux/module.h>
> > +#include <linux/printk.h>
> > +#include <linux/slab.h>
> > +#include <linux/uaccess.h>
> > +
> > +static noinline void __init copy_user_test(void)
> > +{
> > + char *kmem;
> > + char __user *usermem;
> > + size_t size = 10;
> > + int unused;
> > +
> > + kmem = kmalloc(size, GFP_KERNEL);
> > + if (!kmem)
> > + return;
> > +
> > + usermem = (char __user *)vm_mmap(NULL, 0, PAGE_SIZE,
> > + PROT_READ | PROT_WRITE | PROT_EXEC,
> > + MAP_ANONYMOUS | MAP_PRIVATE, 0);
> > + if (IS_ERR(usermem)) {
> > + pr_err("Failed to allocate user memory\n");
> > + kfree(kmem);
> > + return;
> > + }
> > +
> > + pr_info("out-of-bounds in copy_from_user()\n");
> > + unused = copy_from_user(kmem, usermem, size + 1);
> > +
> > + pr_info("out-of-bounds in copy_to_user()\n");
> > + unused = copy_to_user(usermem, kmem, size + 1);
> > +
> > + pr_info("out-of-bounds in __copy_from_user()\n");
> > + unused = __copy_from_user(kmem, usermem, size + 1);
> > +
> > + pr_info("out-of-bounds in __copy_to_user()\n");
> > + unused = __copy_to_user(usermem, kmem, size + 1);
> > +
> > + pr_info("out-of-bounds in __copy_from_user_inatomic()\n");
> > + unused = __copy_from_user_inatomic(kmem, usermem, size + 1);
> > +
> > + pr_info("out-of-bounds in __copy_to_user_inatomic()\n");
> > + unused = __copy_to_user_inatomic(usermem, kmem, size + 1);
> > +
> > + pr_info("out-of-bounds in strncpy_from_user()\n");
> > + unused = strncpy_from_user(kmem, usermem, size + 1);
> > +
> > + vm_munmap((unsigned long)usermem, PAGE_SIZE);
> > + kfree(kmem);
> > +}
> > +
> > +static int __init copy_user_tests_init(void)
> > +{
> > + /*
> > + * Temporarily enable multi-shot mode. Otherwise, we'd only get a
> > + * report for the first case.
> > + */
> > + bool multishot = kasan_save_enable_multi_shot();
> > +
> > + copy_user_test();
> > + kasan_restore_multi_shot(multishot);
> > + return -EAGAIN;
> > +}
> > +
> > +module_init(copy_user_tests_init);
> > +MODULE_LICENSE("GPL");
> > --
> > 2.25.1.696.g5e7596f4ac-goog
> >
> >

--
Best,
Patricia