The currently existing page allocator tests rely on kmalloc fallback with large sizes that is only present for SLUB. Add proper tests that use alloc/free_pages().
Signed-off-by: Andrey Konovalov <andreyk...@google.com> Link: https://linux-review.googlesource.com/id/Ia173d5a1b215fe6b2548d814ef0f4433cf983570 --- lib/test_kasan.c | 54 +++++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 49 insertions(+), 5 deletions(-) diff --git a/lib/test_kasan.c b/lib/test_kasan.c index 6261521e57ad..24798c034d05 100644 --- a/lib/test_kasan.c +++ b/lib/test_kasan.c @@ -128,6 +128,12 @@ static void kmalloc_node_oob_right(struct kunit *test) kfree(ptr); } +/* + * These kmalloc_pagealloc_* tests try allocating a memory chunk that doesn't + * fit into a slab cache and therefore is allocated via the page allocator + * fallback. Since this kind of fallback is only implemented for SLUB, these + * tests are limited to that allocator. + */ static void kmalloc_pagealloc_oob_right(struct kunit *test) { char *ptr; @@ -138,14 +144,11 @@ static void kmalloc_pagealloc_oob_right(struct kunit *test) return; } - /* - * Allocate a chunk that does not fit into a SLUB cache to trigger - * the page allocator fallback. - */ ptr = kmalloc(size, GFP_KERNEL); KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); KUNIT_EXPECT_KASAN_FAIL(test, ptr[size + OOB_TAG_OFF] = 0); + kfree(ptr); } @@ -161,8 +164,8 @@ static void kmalloc_pagealloc_uaf(struct kunit *test) ptr = kmalloc(size, GFP_KERNEL); KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - kfree(ptr); + KUNIT_EXPECT_KASAN_FAIL(test, ptr[0] = 0); } @@ -182,6 +185,45 @@ static void kmalloc_pagealloc_invalid_free(struct kunit *test) KUNIT_EXPECT_KASAN_FAIL(test, kfree(ptr + 1)); } +static void pagealloc_oob_right(struct kunit *test) +{ + char *ptr; + struct page *pages; + size_t order = 4; + size_t size = (1UL << (PAGE_SHIFT + order)); + + /* + * With generic KASAN page allocations have no redzones, thus + * out-of-bounds detection is not guaranteed. + * See https://bugzilla.kernel.org/show_bug.cgi?id=210503. + */ + if (IS_ENABLED(CONFIG_KASAN_GENERIC)) { + kunit_info(test, "skipping, CONFIG_KASAN_GENERIC enabled"); + return; + } + + pages = alloc_pages(GFP_KERNEL, order); + ptr = page_address(pages); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + KUNIT_EXPECT_KASAN_FAIL(test, ptr[size] = 0); + free_pages((unsigned long)ptr, order); +} + +static void pagealloc_uaf(struct kunit *test) +{ + char *ptr; + struct page *pages; + size_t order = 4; + + pages = alloc_pages(GFP_KERNEL, order); + ptr = page_address(pages); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + free_pages((unsigned long)ptr, order); + + KUNIT_EXPECT_KASAN_FAIL(test, ptr[0] = 0); +} + static void kmalloc_large_oob_right(struct kunit *test) { char *ptr; @@ -933,6 +975,8 @@ static struct kunit_case kasan_kunit_test_cases[] = { KUNIT_CASE(kmalloc_pagealloc_oob_right), KUNIT_CASE(kmalloc_pagealloc_uaf), KUNIT_CASE(kmalloc_pagealloc_invalid_free), + KUNIT_CASE(pagealloc_oob_right), + KUNIT_CASE(pagealloc_uaf), KUNIT_CASE(kmalloc_large_oob_right), KUNIT_CASE(kmalloc_oob_krealloc_more), KUNIT_CASE(kmalloc_oob_krealloc_less), -- 2.29.2.729.g45daf8777d-goog
