On Tue, Jan 05, 2021 at 07:27PM +0100, Andrey Konovalov wrote: > 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 <andreyknvl@xxxxxxxxxx> > Link: https://linux-review.googlesource.com/id/Ia173d5a1b215fe6b2548d814ef0f4433cf983570 Reviewed-by: Marco Elver <elver@xxxxxxxxxx> > --- > 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 >
