The patch titled Subject: kasan: move tests to mm/kasan/ has been added to the -mm mm-unstable branch. Its filename is kasan-move-tests-to-mm-kasan.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/kasan-move-tests-to-mm-kasan.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Subject: kasan: move tests to mm/kasan/ Date: Tue, 6 Sep 2022 00:18:36 +0200 Move KASAN tests to mm/kasan/ to keep the test code alongside the implementation. Link: https://lkml.kernel.org/r/676398f0aeecd47d2f8e3369ea0e95563f641a36.1662416260.git.andreyknvl@xxxxxxxxxx Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Cc: Alexander Potapenko <glider@xxxxxxxxxx> Cc: Andrey Konovalov <andreyknvl@xxxxxxxxx> Cc: Andrey Ryabinin <ryabinin.a.a@xxxxxxxxx> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Cc: Marco Elver <elver@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- MAINTAINERS | 1 lib/Makefile | 5 lib/test_kasan.c | 1426 --------------------------------- lib/test_kasan_module.c | 141 --- mm/kasan/Makefile | 8 mm/kasan/kasan_test.c | 1426 +++++++++++++++++++++++++++++++++ mm/kasan/kasan_test_module.c | 141 +++ 7 files changed, 1575 insertions(+), 1573 deletions(-) --- a/lib/Makefile~kasan-move-tests-to-mm-kasan +++ a/lib/Makefile @@ -65,11 +65,6 @@ obj-$(CONFIG_TEST_SYSCTL) += test_sysctl obj-$(CONFIG_TEST_SIPHASH) += test_siphash.o obj-$(CONFIG_HASH_KUNIT_TEST) += test_hash.o obj-$(CONFIG_TEST_IDA) += test_ida.o -obj-$(CONFIG_KASAN_KUNIT_TEST) += test_kasan.o -CFLAGS_test_kasan.o += -fno-builtin -CFLAGS_test_kasan.o += $(call cc-disable-warning, vla) -obj-$(CONFIG_KASAN_MODULE_TEST) += test_kasan_module.o -CFLAGS_test_kasan_module.o += -fno-builtin obj-$(CONFIG_TEST_UBSAN) += test_ubsan.o CFLAGS_test_ubsan.o += $(call cc-disable-warning, vla) UBSAN_SANITIZE_test_ubsan.o := y --- a/lib/test_kasan.c +++ /dev/null @@ -1,1426 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * - * Copyright (c) 2014 Samsung Electronics Co., Ltd. - * Author: Andrey Ryabinin <a.ryabinin@xxxxxxxxxxx> - */ - -#include <linux/bitops.h> -#include <linux/delay.h> -#include <linux/kasan.h> -#include <linux/kernel.h> -#include <linux/mm.h> -#include <linux/mman.h> -#include <linux/module.h> -#include <linux/printk.h> -#include <linux/random.h> -#include <linux/slab.h> -#include <linux/string.h> -#include <linux/uaccess.h> -#include <linux/io.h> -#include <linux/vmalloc.h> -#include <linux/set_memory.h> - -#include <asm/page.h> - -#include <kunit/test.h> - -#include "../mm/kasan/kasan.h" - -#define OOB_TAG_OFF (IS_ENABLED(CONFIG_KASAN_GENERIC) ? 0 : KASAN_GRANULE_SIZE) - -/* - * Some tests use these global variables to store return values from function - * calls that could otherwise be eliminated by the compiler as dead code. - */ -void *kasan_ptr_result; -int kasan_int_result; - -static struct kunit_resource resource; -static struct kunit_kasan_status test_status; -static bool multishot; - -/* - * Temporarily enable multi-shot mode. Otherwise, KASAN would only report the - * first detected bug and panic the kernel if panic_on_warn is enabled. For - * hardware tag-based KASAN also allow tag checking to be reenabled for each - * test, see the comment for KUNIT_EXPECT_KASAN_FAIL(). - */ -static int kasan_test_init(struct kunit *test) -{ - if (!kasan_enabled()) { - kunit_err(test, "can't run KASAN tests with KASAN disabled"); - return -1; - } - - multishot = kasan_save_enable_multi_shot(); - test_status.report_found = false; - test_status.sync_fault = false; - kunit_add_named_resource(test, NULL, NULL, &resource, - "kasan_status", &test_status); - return 0; -} - -static void kasan_test_exit(struct kunit *test) -{ - kasan_restore_multi_shot(multishot); - KUNIT_EXPECT_FALSE(test, test_status.report_found); -} - -/** - * KUNIT_EXPECT_KASAN_FAIL() - check that the executed expression produces a - * KASAN report; causes a test failure otherwise. This relies on a KUnit - * resource named "kasan_status". Do not use this name for KUnit resources - * outside of KASAN tests. - * - * For hardware tag-based KASAN, when a synchronous tag fault happens, tag - * checking is auto-disabled. When this happens, this test handler reenables - * tag checking. As tag checking can be only disabled or enabled per CPU, - * this handler disables migration (preemption). - * - * Since the compiler doesn't see that the expression can change the test_status - * fields, it can reorder or optimize away the accesses to those fields. - * Use READ/WRITE_ONCE() for the accesses and compiler barriers around the - * expression to prevent that. - * - * In between KUNIT_EXPECT_KASAN_FAIL checks, test_status.report_found is kept - * as false. This allows detecting KASAN reports that happen outside of the - * checks by asserting !test_status.report_found at the start of - * KUNIT_EXPECT_KASAN_FAIL and in kasan_test_exit. - */ -#define KUNIT_EXPECT_KASAN_FAIL(test, expression) do { \ - if (IS_ENABLED(CONFIG_KASAN_HW_TAGS) && \ - kasan_sync_fault_possible()) \ - migrate_disable(); \ - KUNIT_EXPECT_FALSE(test, READ_ONCE(test_status.report_found)); \ - barrier(); \ - expression; \ - barrier(); \ - if (kasan_async_fault_possible()) \ - kasan_force_async_fault(); \ - if (!READ_ONCE(test_status.report_found)) { \ - KUNIT_FAIL(test, KUNIT_SUBTEST_INDENT "KASAN failure " \ - "expected in \"" #expression \ - "\", but none occurred"); \ - } \ - if (IS_ENABLED(CONFIG_KASAN_HW_TAGS) && \ - kasan_sync_fault_possible()) { \ - if (READ_ONCE(test_status.report_found) && \ - READ_ONCE(test_status.sync_fault)) \ - kasan_enable_tagging(); \ - migrate_enable(); \ - } \ - WRITE_ONCE(test_status.report_found, false); \ -} while (0) - -#define KASAN_TEST_NEEDS_CONFIG_ON(test, config) do { \ - if (!IS_ENABLED(config)) \ - kunit_skip((test), "Test requires " #config "=y"); \ -} while (0) - -#define KASAN_TEST_NEEDS_CONFIG_OFF(test, config) do { \ - if (IS_ENABLED(config)) \ - kunit_skip((test), "Test requires " #config "=n"); \ -} while (0) - -static void kmalloc_oob_right(struct kunit *test) -{ - char *ptr; - size_t size = 128 - KASAN_GRANULE_SIZE - 5; - - ptr = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - OPTIMIZER_HIDE_VAR(ptr); - /* - * An unaligned access past the requested kmalloc size. - * Only generic KASAN can precisely detect these. - */ - if (IS_ENABLED(CONFIG_KASAN_GENERIC)) - KUNIT_EXPECT_KASAN_FAIL(test, ptr[size] = 'x'); - - /* - * An aligned access into the first out-of-bounds granule that falls - * within the aligned kmalloc object. - */ - KUNIT_EXPECT_KASAN_FAIL(test, ptr[size + 5] = 'y'); - - /* Out-of-bounds access past the aligned kmalloc object. */ - KUNIT_EXPECT_KASAN_FAIL(test, ptr[0] = - ptr[size + KASAN_GRANULE_SIZE + 5]); - - kfree(ptr); -} - -static void kmalloc_oob_left(struct kunit *test) -{ - char *ptr; - size_t size = 15; - - ptr = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - OPTIMIZER_HIDE_VAR(ptr); - KUNIT_EXPECT_KASAN_FAIL(test, *ptr = *(ptr - 1)); - kfree(ptr); -} - -static void kmalloc_node_oob_right(struct kunit *test) -{ - char *ptr; - size_t size = 4096; - - ptr = kmalloc_node(size, GFP_KERNEL, 0); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - OPTIMIZER_HIDE_VAR(ptr); - KUNIT_EXPECT_KASAN_FAIL(test, ptr[0] = ptr[size]); - 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; - size_t size = KMALLOC_MAX_CACHE_SIZE + 10; - - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_SLUB); - - ptr = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - OPTIMIZER_HIDE_VAR(ptr); - KUNIT_EXPECT_KASAN_FAIL(test, ptr[size + OOB_TAG_OFF] = 0); - - kfree(ptr); -} - -static void kmalloc_pagealloc_uaf(struct kunit *test) -{ - char *ptr; - size_t size = KMALLOC_MAX_CACHE_SIZE + 10; - - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_SLUB); - - ptr = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - kfree(ptr); - - KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[0]); -} - -static void kmalloc_pagealloc_invalid_free(struct kunit *test) -{ - char *ptr; - size_t size = KMALLOC_MAX_CACHE_SIZE + 10; - - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_SLUB); - - ptr = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - 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. - */ - KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_GENERIC); - - pages = alloc_pages(GFP_KERNEL, order); - ptr = page_address(pages); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - KUNIT_EXPECT_KASAN_FAIL(test, ptr[0] = ptr[size]); - 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, ((volatile char *)ptr)[0]); -} - -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. - */ - ptr = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - OPTIMIZER_HIDE_VAR(ptr); - KUNIT_EXPECT_KASAN_FAIL(test, ptr[size] = 0); - kfree(ptr); -} - -static void krealloc_more_oob_helper(struct kunit *test, - size_t size1, size_t size2) -{ - char *ptr1, *ptr2; - size_t middle; - - KUNIT_ASSERT_LT(test, size1, size2); - middle = size1 + (size2 - size1) / 2; - - ptr1 = kmalloc(size1, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1); - - ptr2 = krealloc(ptr1, size2, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2); - - /* All offsets up to size2 must be accessible. */ - ptr2[size1 - 1] = 'x'; - ptr2[size1] = 'x'; - ptr2[middle] = 'x'; - ptr2[size2 - 1] = 'x'; - - /* Generic mode is precise, so unaligned size2 must be inaccessible. */ - if (IS_ENABLED(CONFIG_KASAN_GENERIC)) - KUNIT_EXPECT_KASAN_FAIL(test, ptr2[size2] = 'x'); - - /* For all modes first aligned offset after size2 must be inaccessible. */ - KUNIT_EXPECT_KASAN_FAIL(test, - ptr2[round_up(size2, KASAN_GRANULE_SIZE)] = 'x'); - - kfree(ptr2); -} - -static void krealloc_less_oob_helper(struct kunit *test, - size_t size1, size_t size2) -{ - char *ptr1, *ptr2; - size_t middle; - - KUNIT_ASSERT_LT(test, size2, size1); - middle = size2 + (size1 - size2) / 2; - - ptr1 = kmalloc(size1, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1); - - ptr2 = krealloc(ptr1, size2, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2); - - /* Must be accessible for all modes. */ - ptr2[size2 - 1] = 'x'; - - /* Generic mode is precise, so unaligned size2 must be inaccessible. */ - if (IS_ENABLED(CONFIG_KASAN_GENERIC)) - KUNIT_EXPECT_KASAN_FAIL(test, ptr2[size2] = 'x'); - - /* For all modes first aligned offset after size2 must be inaccessible. */ - KUNIT_EXPECT_KASAN_FAIL(test, - ptr2[round_up(size2, KASAN_GRANULE_SIZE)] = 'x'); - - /* - * For all modes all size2, middle, and size1 should land in separate - * granules and thus the latter two offsets should be inaccessible. - */ - KUNIT_EXPECT_LE(test, round_up(size2, KASAN_GRANULE_SIZE), - round_down(middle, KASAN_GRANULE_SIZE)); - KUNIT_EXPECT_LE(test, round_up(middle, KASAN_GRANULE_SIZE), - round_down(size1, KASAN_GRANULE_SIZE)); - KUNIT_EXPECT_KASAN_FAIL(test, ptr2[middle] = 'x'); - KUNIT_EXPECT_KASAN_FAIL(test, ptr2[size1 - 1] = 'x'); - KUNIT_EXPECT_KASAN_FAIL(test, ptr2[size1] = 'x'); - - kfree(ptr2); -} - -static void krealloc_more_oob(struct kunit *test) -{ - krealloc_more_oob_helper(test, 201, 235); -} - -static void krealloc_less_oob(struct kunit *test) -{ - krealloc_less_oob_helper(test, 235, 201); -} - -static void krealloc_pagealloc_more_oob(struct kunit *test) -{ - /* page_alloc fallback in only implemented for SLUB. */ - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_SLUB); - - krealloc_more_oob_helper(test, KMALLOC_MAX_CACHE_SIZE + 201, - KMALLOC_MAX_CACHE_SIZE + 235); -} - -static void krealloc_pagealloc_less_oob(struct kunit *test) -{ - /* page_alloc fallback in only implemented for SLUB. */ - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_SLUB); - - krealloc_less_oob_helper(test, KMALLOC_MAX_CACHE_SIZE + 235, - KMALLOC_MAX_CACHE_SIZE + 201); -} - -/* - * Check that krealloc() detects a use-after-free, returns NULL, - * and doesn't unpoison the freed object. - */ -static void krealloc_uaf(struct kunit *test) -{ - char *ptr1, *ptr2; - int size1 = 201; - int size2 = 235; - - ptr1 = kmalloc(size1, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1); - kfree(ptr1); - - KUNIT_EXPECT_KASAN_FAIL(test, ptr2 = krealloc(ptr1, size2, GFP_KERNEL)); - KUNIT_ASSERT_NULL(test, ptr2); - KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)ptr1); -} - -static void kmalloc_oob_16(struct kunit *test) -{ - struct { - u64 words[2]; - } *ptr1, *ptr2; - - /* This test is specifically crafted for the generic mode. */ - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); - - ptr1 = kmalloc(sizeof(*ptr1) - 3, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1); - - ptr2 = kmalloc(sizeof(*ptr2), GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2); - - OPTIMIZER_HIDE_VAR(ptr1); - OPTIMIZER_HIDE_VAR(ptr2); - KUNIT_EXPECT_KASAN_FAIL(test, *ptr1 = *ptr2); - kfree(ptr1); - kfree(ptr2); -} - -static void kmalloc_uaf_16(struct kunit *test) -{ - struct { - u64 words[2]; - } *ptr1, *ptr2; - - ptr1 = kmalloc(sizeof(*ptr1), GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1); - - ptr2 = kmalloc(sizeof(*ptr2), GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2); - kfree(ptr2); - - KUNIT_EXPECT_KASAN_FAIL(test, *ptr1 = *ptr2); - kfree(ptr1); -} - -/* - * Note: in the memset tests below, the written range touches both valid and - * invalid memory. This makes sure that the instrumentation does not only check - * the starting address but the whole range. - */ - -static void kmalloc_oob_memset_2(struct kunit *test) -{ - char *ptr; - size_t size = 128 - KASAN_GRANULE_SIZE; - - ptr = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - OPTIMIZER_HIDE_VAR(size); - KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr + size - 1, 0, 2)); - kfree(ptr); -} - -static void kmalloc_oob_memset_4(struct kunit *test) -{ - char *ptr; - size_t size = 128 - KASAN_GRANULE_SIZE; - - ptr = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - OPTIMIZER_HIDE_VAR(size); - KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr + size - 3, 0, 4)); - kfree(ptr); -} - -static void kmalloc_oob_memset_8(struct kunit *test) -{ - char *ptr; - size_t size = 128 - KASAN_GRANULE_SIZE; - - ptr = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - OPTIMIZER_HIDE_VAR(size); - KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr + size - 7, 0, 8)); - kfree(ptr); -} - -static void kmalloc_oob_memset_16(struct kunit *test) -{ - char *ptr; - size_t size = 128 - KASAN_GRANULE_SIZE; - - ptr = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - OPTIMIZER_HIDE_VAR(size); - KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr + size - 15, 0, 16)); - kfree(ptr); -} - -static void kmalloc_oob_in_memset(struct kunit *test) -{ - char *ptr; - size_t size = 128 - KASAN_GRANULE_SIZE; - - ptr = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - OPTIMIZER_HIDE_VAR(ptr); - OPTIMIZER_HIDE_VAR(size); - KUNIT_EXPECT_KASAN_FAIL(test, - memset(ptr, 0, size + KASAN_GRANULE_SIZE)); - kfree(ptr); -} - -static void kmalloc_memmove_negative_size(struct kunit *test) -{ - char *ptr; - size_t size = 64; - size_t invalid_size = -2; - - /* - * Hardware tag-based mode doesn't check memmove for negative size. - * As a result, this test introduces a side-effect memory corruption, - * which can result in a crash. - */ - KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_HW_TAGS); - - ptr = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - memset((char *)ptr, 0, 64); - OPTIMIZER_HIDE_VAR(ptr); - OPTIMIZER_HIDE_VAR(invalid_size); - KUNIT_EXPECT_KASAN_FAIL(test, - memmove((char *)ptr, (char *)ptr + 4, invalid_size)); - kfree(ptr); -} - -static void kmalloc_memmove_invalid_size(struct kunit *test) -{ - char *ptr; - size_t size = 64; - volatile size_t invalid_size = size; - - ptr = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - memset((char *)ptr, 0, 64); - OPTIMIZER_HIDE_VAR(ptr); - KUNIT_EXPECT_KASAN_FAIL(test, - memmove((char *)ptr, (char *)ptr + 4, invalid_size)); - kfree(ptr); -} - -static void kmalloc_uaf(struct kunit *test) -{ - char *ptr; - size_t size = 10; - - ptr = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - kfree(ptr); - KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[8]); -} - -static void kmalloc_uaf_memset(struct kunit *test) -{ - char *ptr; - size_t size = 33; - - /* - * Only generic KASAN uses quarantine, which is required to avoid a - * kernel memory corruption this test causes. - */ - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); - - ptr = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - kfree(ptr); - KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr, 0, size)); -} - -static void kmalloc_uaf2(struct kunit *test) -{ - char *ptr1, *ptr2; - size_t size = 43; - int counter = 0; - -again: - ptr1 = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1); - - kfree(ptr1); - - ptr2 = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2); - - /* - * For tag-based KASAN ptr1 and ptr2 tags might happen to be the same. - * Allow up to 16 attempts at generating different tags. - */ - if (!IS_ENABLED(CONFIG_KASAN_GENERIC) && ptr1 == ptr2 && counter++ < 16) { - kfree(ptr2); - goto again; - } - - KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr1)[40]); - KUNIT_EXPECT_PTR_NE(test, ptr1, ptr2); - - kfree(ptr2); -} - -static void kfree_via_page(struct kunit *test) -{ - char *ptr; - size_t size = 8; - struct page *page; - unsigned long offset; - - ptr = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - page = virt_to_page(ptr); - offset = offset_in_page(ptr); - kfree(page_address(page) + offset); -} - -static void kfree_via_phys(struct kunit *test) -{ - char *ptr; - size_t size = 8; - phys_addr_t phys; - - ptr = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - phys = virt_to_phys(ptr); - kfree(phys_to_virt(phys)); -} - -static void kmem_cache_oob(struct kunit *test) -{ - char *p; - size_t size = 200; - struct kmem_cache *cache; - - cache = kmem_cache_create("test_cache", size, 0, 0, NULL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache); - - p = kmem_cache_alloc(cache, GFP_KERNEL); - if (!p) { - kunit_err(test, "Allocation failed: %s\n", __func__); - kmem_cache_destroy(cache); - return; - } - - KUNIT_EXPECT_KASAN_FAIL(test, *p = p[size + OOB_TAG_OFF]); - - kmem_cache_free(cache, p); - kmem_cache_destroy(cache); -} - -static void kmem_cache_accounted(struct kunit *test) -{ - int i; - char *p; - size_t size = 200; - struct kmem_cache *cache; - - cache = kmem_cache_create("test_cache", size, 0, SLAB_ACCOUNT, NULL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache); - - /* - * Several allocations with a delay to allow for lazy per memcg kmem - * cache creation. - */ - for (i = 0; i < 5; i++) { - p = kmem_cache_alloc(cache, GFP_KERNEL); - if (!p) - goto free_cache; - - kmem_cache_free(cache, p); - msleep(100); - } - -free_cache: - kmem_cache_destroy(cache); -} - -static void kmem_cache_bulk(struct kunit *test) -{ - struct kmem_cache *cache; - size_t size = 200; - char *p[10]; - bool ret; - int i; - - cache = kmem_cache_create("test_cache", size, 0, 0, NULL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache); - - ret = kmem_cache_alloc_bulk(cache, GFP_KERNEL, ARRAY_SIZE(p), (void **)&p); - if (!ret) { - kunit_err(test, "Allocation failed: %s\n", __func__); - kmem_cache_destroy(cache); - return; - } - - for (i = 0; i < ARRAY_SIZE(p); i++) - p[i][0] = p[i][size - 1] = 42; - - kmem_cache_free_bulk(cache, ARRAY_SIZE(p), (void **)&p); - kmem_cache_destroy(cache); -} - -static char global_array[10]; - -static void kasan_global_oob_right(struct kunit *test) -{ - /* - * Deliberate out-of-bounds access. To prevent CONFIG_UBSAN_LOCAL_BOUNDS - * from failing here and panicking the kernel, access the array via a - * volatile pointer, which will prevent the compiler from being able to - * determine the array bounds. - * - * This access uses a volatile pointer to char (char *volatile) rather - * than the more conventional pointer to volatile char (volatile char *) - * because we want to prevent the compiler from making inferences about - * the pointer itself (i.e. its array bounds), not the data that it - * refers to. - */ - char *volatile array = global_array; - char *p = &array[ARRAY_SIZE(global_array) + 3]; - - /* Only generic mode instruments globals. */ - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); - - KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p); -} - -static void kasan_global_oob_left(struct kunit *test) -{ - char *volatile array = global_array; - char *p = array - 3; - - /* - * GCC is known to fail this test, skip it. - * See https://bugzilla.kernel.org/show_bug.cgi?id=215051. - */ - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_CC_IS_CLANG); - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); - KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p); -} - -/* Check that ksize() makes the whole object accessible. */ -static void ksize_unpoisons_memory(struct kunit *test) -{ - char *ptr; - size_t size = 123, real_size; - - ptr = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - real_size = ksize(ptr); - - OPTIMIZER_HIDE_VAR(ptr); - - /* This access shouldn't trigger a KASAN report. */ - ptr[size] = 'x'; - - /* This one must. */ - KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[real_size]); - - kfree(ptr); -} - -/* - * Check that a use-after-free is detected by ksize() and via normal accesses - * after it. - */ -static void ksize_uaf(struct kunit *test) -{ - char *ptr; - int size = 128 - KASAN_GRANULE_SIZE; - - ptr = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - kfree(ptr); - - OPTIMIZER_HIDE_VAR(ptr); - KUNIT_EXPECT_KASAN_FAIL(test, ksize(ptr)); - KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[0]); - KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[size]); -} - -static void kasan_stack_oob(struct kunit *test) -{ - char stack_array[10]; - /* See comment in kasan_global_oob_right. */ - char *volatile array = stack_array; - char *p = &array[ARRAY_SIZE(stack_array) + OOB_TAG_OFF]; - - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_STACK); - - KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p); -} - -static void kasan_alloca_oob_left(struct kunit *test) -{ - volatile int i = 10; - char alloca_array[i]; - /* See comment in kasan_global_oob_right. */ - char *volatile array = alloca_array; - char *p = array - 1; - - /* Only generic mode instruments dynamic allocas. */ - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_STACK); - - KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p); -} - -static void kasan_alloca_oob_right(struct kunit *test) -{ - volatile int i = 10; - char alloca_array[i]; - /* See comment in kasan_global_oob_right. */ - char *volatile array = alloca_array; - char *p = array + i; - - /* Only generic mode instruments dynamic allocas. */ - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_STACK); - - KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p); -} - -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); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache); - - p = kmem_cache_alloc(cache, GFP_KERNEL); - if (!p) { - kunit_err(test, "Allocation failed: %s\n", __func__); - kmem_cache_destroy(cache); - return; - } - - kmem_cache_free(cache, p); - KUNIT_EXPECT_KASAN_FAIL(test, kmem_cache_free(cache, p)); - kmem_cache_destroy(cache); -} - -static void kmem_cache_invalid_free(struct kunit *test) -{ - char *p; - size_t size = 200; - struct kmem_cache *cache; - - cache = kmem_cache_create("test_cache", size, 0, SLAB_TYPESAFE_BY_RCU, - NULL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache); - - p = kmem_cache_alloc(cache, GFP_KERNEL); - if (!p) { - kunit_err(test, "Allocation failed: %s\n", __func__); - kmem_cache_destroy(cache); - return; - } - - /* Trigger invalid free, the object doesn't get freed. */ - KUNIT_EXPECT_KASAN_FAIL(test, kmem_cache_free(cache, p + 1)); - - /* - * Properly free the object to prevent the "Objects remaining in - * test_cache on __kmem_cache_shutdown" BUG failure. - */ - kmem_cache_free(cache, p); - - kmem_cache_destroy(cache); -} - -static void empty_cache_ctor(void *object) { } - -static void kmem_cache_double_destroy(struct kunit *test) -{ - struct kmem_cache *cache; - - /* Provide a constructor to prevent cache merging. */ - cache = kmem_cache_create("test_cache", 200, 0, 0, empty_cache_ctor); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache); - kmem_cache_destroy(cache); - KUNIT_EXPECT_KASAN_FAIL(test, kmem_cache_destroy(cache)); -} - -static void kasan_memchr(struct kunit *test) -{ - char *ptr; - size_t size = 24; - - /* - * str* functions are not instrumented with CONFIG_AMD_MEM_ENCRYPT. - * See https://bugzilla.kernel.org/show_bug.cgi?id=206337 for details. - */ - KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_AMD_MEM_ENCRYPT); - - if (OOB_TAG_OFF) - size = round_up(size, OOB_TAG_OFF); - - ptr = kmalloc(size, GFP_KERNEL | __GFP_ZERO); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - OPTIMIZER_HIDE_VAR(ptr); - OPTIMIZER_HIDE_VAR(size); - KUNIT_EXPECT_KASAN_FAIL(test, - kasan_ptr_result = memchr(ptr, '1', size + 1)); - - kfree(ptr); -} - -static void kasan_memcmp(struct kunit *test) -{ - char *ptr; - size_t size = 24; - int arr[9]; - - /* - * str* functions are not instrumented with CONFIG_AMD_MEM_ENCRYPT. - * See https://bugzilla.kernel.org/show_bug.cgi?id=206337 for details. - */ - KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_AMD_MEM_ENCRYPT); - - if (OOB_TAG_OFF) - size = round_up(size, OOB_TAG_OFF); - - ptr = kmalloc(size, GFP_KERNEL | __GFP_ZERO); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - memset(arr, 0, sizeof(arr)); - - OPTIMIZER_HIDE_VAR(ptr); - OPTIMIZER_HIDE_VAR(size); - KUNIT_EXPECT_KASAN_FAIL(test, - kasan_int_result = memcmp(ptr, arr, size+1)); - kfree(ptr); -} - -static void kasan_strings(struct kunit *test) -{ - char *ptr; - size_t size = 24; - - /* - * str* functions are not instrumented with CONFIG_AMD_MEM_ENCRYPT. - * See https://bugzilla.kernel.org/show_bug.cgi?id=206337 for details. - */ - KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_AMD_MEM_ENCRYPT); - - ptr = kmalloc(size, GFP_KERNEL | __GFP_ZERO); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - kfree(ptr); - - /* - * Try to cause only 1 invalid access (less spam in dmesg). - * For that we need ptr to point to zeroed byte. - * Skip metadata that could be stored in freed object so ptr - * will likely point to zeroed byte. - */ - ptr += 16; - KUNIT_EXPECT_KASAN_FAIL(test, kasan_ptr_result = strchr(ptr, '1')); - - KUNIT_EXPECT_KASAN_FAIL(test, kasan_ptr_result = strrchr(ptr, '1')); - - KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = strcmp(ptr, "2")); - - KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = strncmp(ptr, "2", 1)); - - KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = strlen(ptr)); - - KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = strnlen(ptr, 1)); -} - -static void kasan_bitops_modify(struct kunit *test, int nr, void *addr) -{ - KUNIT_EXPECT_KASAN_FAIL(test, set_bit(nr, addr)); - KUNIT_EXPECT_KASAN_FAIL(test, __set_bit(nr, addr)); - KUNIT_EXPECT_KASAN_FAIL(test, clear_bit(nr, addr)); - KUNIT_EXPECT_KASAN_FAIL(test, __clear_bit(nr, addr)); - KUNIT_EXPECT_KASAN_FAIL(test, clear_bit_unlock(nr, addr)); - KUNIT_EXPECT_KASAN_FAIL(test, __clear_bit_unlock(nr, addr)); - KUNIT_EXPECT_KASAN_FAIL(test, change_bit(nr, addr)); - KUNIT_EXPECT_KASAN_FAIL(test, __change_bit(nr, addr)); -} - -static void kasan_bitops_test_and_modify(struct kunit *test, int nr, void *addr) -{ - KUNIT_EXPECT_KASAN_FAIL(test, test_and_set_bit(nr, addr)); - KUNIT_EXPECT_KASAN_FAIL(test, __test_and_set_bit(nr, addr)); - KUNIT_EXPECT_KASAN_FAIL(test, test_and_set_bit_lock(nr, addr)); - KUNIT_EXPECT_KASAN_FAIL(test, test_and_clear_bit(nr, addr)); - KUNIT_EXPECT_KASAN_FAIL(test, __test_and_clear_bit(nr, addr)); - KUNIT_EXPECT_KASAN_FAIL(test, test_and_change_bit(nr, addr)); - KUNIT_EXPECT_KASAN_FAIL(test, __test_and_change_bit(nr, addr)); - KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = test_bit(nr, addr)); - -#if defined(clear_bit_unlock_is_negative_byte) - KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = - clear_bit_unlock_is_negative_byte(nr, addr)); -#endif -} - -static void kasan_bitops_generic(struct kunit *test) -{ - long *bits; - - /* This test is specifically crafted for the generic mode. */ - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); - - /* - * Allocate 1 more byte, which causes kzalloc to round up to 16 bytes; - * this way we do not actually corrupt other memory. - */ - bits = kzalloc(sizeof(*bits) + 1, GFP_KERNEL); - 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. - */ - kasan_bitops_modify(test, BITS_PER_LONG, bits); - - /* - * Below calls try to access bit beyond allocated memory. - */ - kasan_bitops_test_and_modify(test, BITS_PER_LONG + BITS_PER_BYTE, bits); - - kfree(bits); -} - -static void kasan_bitops_tags(struct kunit *test) -{ - long *bits; - - /* This test is specifically crafted for tag-based modes. */ - KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_GENERIC); - - /* kmalloc-64 cache will be used and the last 16 bytes will be the redzone. */ - bits = kzalloc(48, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, bits); - - /* Do the accesses past the 48 allocated bytes, but within the redone. */ - kasan_bitops_modify(test, BITS_PER_LONG, (void *)bits + 48); - kasan_bitops_test_and_modify(test, BITS_PER_LONG + BITS_PER_BYTE, (void *)bits + 48); - - kfree(bits); -} - -static void kmalloc_double_kzfree(struct kunit *test) -{ - char *ptr; - size_t size = 16; - - ptr = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - kfree_sensitive(ptr); - KUNIT_EXPECT_KASAN_FAIL(test, kfree_sensitive(ptr)); -} - -static void vmalloc_helpers_tags(struct kunit *test) -{ - void *ptr; - - /* This test is intended for tag-based modes. */ - KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_GENERIC); - - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_VMALLOC); - - ptr = vmalloc(PAGE_SIZE); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - /* Check that the returned pointer is tagged. */ - KUNIT_EXPECT_GE(test, (u8)get_tag(ptr), (u8)KASAN_TAG_MIN); - KUNIT_EXPECT_LT(test, (u8)get_tag(ptr), (u8)KASAN_TAG_KERNEL); - - /* Make sure exported vmalloc helpers handle tagged pointers. */ - KUNIT_ASSERT_TRUE(test, is_vmalloc_addr(ptr)); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, vmalloc_to_page(ptr)); - -#if !IS_MODULE(CONFIG_KASAN_KUNIT_TEST) - { - int rv; - - /* Make sure vmalloc'ed memory permissions can be changed. */ - rv = set_memory_ro((unsigned long)ptr, 1); - KUNIT_ASSERT_GE(test, rv, 0); - rv = set_memory_rw((unsigned long)ptr, 1); - KUNIT_ASSERT_GE(test, rv, 0); - } -#endif - - vfree(ptr); -} - -static void vmalloc_oob(struct kunit *test) -{ - char *v_ptr, *p_ptr; - struct page *page; - size_t size = PAGE_SIZE / 2 - KASAN_GRANULE_SIZE - 5; - - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_VMALLOC); - - v_ptr = vmalloc(size); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, v_ptr); - - OPTIMIZER_HIDE_VAR(v_ptr); - - /* - * We have to be careful not to hit the guard page in vmalloc tests. - * The MMU will catch that and crash us. - */ - - /* Make sure in-bounds accesses are valid. */ - v_ptr[0] = 0; - v_ptr[size - 1] = 0; - - /* - * An unaligned access past the requested vmalloc size. - * Only generic KASAN can precisely detect these. - */ - if (IS_ENABLED(CONFIG_KASAN_GENERIC)) - KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)v_ptr)[size]); - - /* An aligned access into the first out-of-bounds granule. */ - KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)v_ptr)[size + 5]); - - /* Check that in-bounds accesses to the physical page are valid. */ - page = vmalloc_to_page(v_ptr); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, page); - p_ptr = page_address(page); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, p_ptr); - p_ptr[0] = 0; - - vfree(v_ptr); - - /* - * We can't check for use-after-unmap bugs in this nor in the following - * vmalloc tests, as the page might be fully unmapped and accessing it - * will crash the kernel. - */ -} - -static void vmap_tags(struct kunit *test) -{ - char *p_ptr, *v_ptr; - struct page *p_page, *v_page; - - /* - * This test is specifically crafted for the software tag-based mode, - * the only tag-based mode that poisons vmap mappings. - */ - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_SW_TAGS); - - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_VMALLOC); - - p_page = alloc_pages(GFP_KERNEL, 1); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, p_page); - p_ptr = page_address(p_page); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, p_ptr); - - v_ptr = vmap(&p_page, 1, VM_MAP, PAGE_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, v_ptr); - - /* - * We can't check for out-of-bounds bugs in this nor in the following - * vmalloc tests, as allocations have page granularity and accessing - * the guard page will crash the kernel. - */ - - KUNIT_EXPECT_GE(test, (u8)get_tag(v_ptr), (u8)KASAN_TAG_MIN); - KUNIT_EXPECT_LT(test, (u8)get_tag(v_ptr), (u8)KASAN_TAG_KERNEL); - - /* Make sure that in-bounds accesses through both pointers work. */ - *p_ptr = 0; - *v_ptr = 0; - - /* Make sure vmalloc_to_page() correctly recovers the page pointer. */ - v_page = vmalloc_to_page(v_ptr); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, v_page); - KUNIT_EXPECT_PTR_EQ(test, p_page, v_page); - - vunmap(v_ptr); - free_pages((unsigned long)p_ptr, 1); -} - -static void vm_map_ram_tags(struct kunit *test) -{ - char *p_ptr, *v_ptr; - struct page *page; - - /* - * This test is specifically crafted for the software tag-based mode, - * the only tag-based mode that poisons vm_map_ram mappings. - */ - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_SW_TAGS); - - page = alloc_pages(GFP_KERNEL, 1); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, page); - p_ptr = page_address(page); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, p_ptr); - - v_ptr = vm_map_ram(&page, 1, -1); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, v_ptr); - - KUNIT_EXPECT_GE(test, (u8)get_tag(v_ptr), (u8)KASAN_TAG_MIN); - KUNIT_EXPECT_LT(test, (u8)get_tag(v_ptr), (u8)KASAN_TAG_KERNEL); - - /* Make sure that in-bounds accesses through both pointers work. */ - *p_ptr = 0; - *v_ptr = 0; - - vm_unmap_ram(v_ptr, 1); - free_pages((unsigned long)p_ptr, 1); -} - -static void vmalloc_percpu(struct kunit *test) -{ - char __percpu *ptr; - int cpu; - - /* - * This test is specifically crafted for the software tag-based mode, - * the only tag-based mode that poisons percpu mappings. - */ - KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_SW_TAGS); - - ptr = __alloc_percpu(PAGE_SIZE, PAGE_SIZE); - - for_each_possible_cpu(cpu) { - char *c_ptr = per_cpu_ptr(ptr, cpu); - - KUNIT_EXPECT_GE(test, (u8)get_tag(c_ptr), (u8)KASAN_TAG_MIN); - KUNIT_EXPECT_LT(test, (u8)get_tag(c_ptr), (u8)KASAN_TAG_KERNEL); - - /* Make sure that in-bounds accesses don't crash the kernel. */ - *c_ptr = 0; - } - - free_percpu(ptr); -} - -/* - * Check that the assigned pointer tag falls within the [KASAN_TAG_MIN, - * KASAN_TAG_KERNEL) range (note: excluding the match-all tag) for tag-based - * modes. - */ -static void match_all_not_assigned(struct kunit *test) -{ - char *ptr; - struct page *pages; - int i, size, order; - - KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_GENERIC); - - for (i = 0; i < 256; i++) { - size = (get_random_int() % 1024) + 1; - ptr = kmalloc(size, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - KUNIT_EXPECT_GE(test, (u8)get_tag(ptr), (u8)KASAN_TAG_MIN); - KUNIT_EXPECT_LT(test, (u8)get_tag(ptr), (u8)KASAN_TAG_KERNEL); - kfree(ptr); - } - - for (i = 0; i < 256; i++) { - order = (get_random_int() % 4) + 1; - pages = alloc_pages(GFP_KERNEL, order); - ptr = page_address(pages); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - KUNIT_EXPECT_GE(test, (u8)get_tag(ptr), (u8)KASAN_TAG_MIN); - KUNIT_EXPECT_LT(test, (u8)get_tag(ptr), (u8)KASAN_TAG_KERNEL); - free_pages((unsigned long)ptr, order); - } - - if (!IS_ENABLED(CONFIG_KASAN_VMALLOC)) - return; - - for (i = 0; i < 256; i++) { - size = (get_random_int() % 1024) + 1; - ptr = vmalloc(size); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - KUNIT_EXPECT_GE(test, (u8)get_tag(ptr), (u8)KASAN_TAG_MIN); - KUNIT_EXPECT_LT(test, (u8)get_tag(ptr), (u8)KASAN_TAG_KERNEL); - vfree(ptr); - } -} - -/* Check that 0xff works as a match-all pointer tag for tag-based modes. */ -static void match_all_ptr_tag(struct kunit *test) -{ - char *ptr; - u8 tag; - - KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_GENERIC); - - ptr = kmalloc(128, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - - /* Backup the assigned tag. */ - tag = get_tag(ptr); - KUNIT_EXPECT_NE(test, tag, (u8)KASAN_TAG_KERNEL); - - /* Reset the tag to 0xff.*/ - ptr = set_tag(ptr, KASAN_TAG_KERNEL); - - /* This access shouldn't trigger a KASAN report. */ - *ptr = 0; - - /* Recover the pointer tag and free. */ - ptr = set_tag(ptr, tag); - kfree(ptr); -} - -/* Check that there are no match-all memory tags for tag-based modes. */ -static void match_all_mem_tag(struct kunit *test) -{ - char *ptr; - int tag; - - KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_GENERIC); - - ptr = kmalloc(128, GFP_KERNEL); - KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); - KUNIT_EXPECT_NE(test, (u8)get_tag(ptr), (u8)KASAN_TAG_KERNEL); - - /* For each possible tag value not matching the pointer tag. */ - for (tag = KASAN_TAG_MIN; tag <= KASAN_TAG_KERNEL; tag++) { - if (tag == get_tag(ptr)) - continue; - - /* Mark the first memory granule with the chosen memory tag. */ - kasan_poison(ptr, KASAN_GRANULE_SIZE, (u8)tag, false); - - /* This access must cause a KASAN report. */ - KUNIT_EXPECT_KASAN_FAIL(test, *ptr = 0); - } - - /* Recover the memory tag and free. */ - kasan_poison(ptr, KASAN_GRANULE_SIZE, get_tag(ptr), false); - kfree(ptr); -} - -static struct kunit_case kasan_kunit_test_cases[] = { - KUNIT_CASE(kmalloc_oob_right), - KUNIT_CASE(kmalloc_oob_left), - KUNIT_CASE(kmalloc_node_oob_right), - 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(krealloc_more_oob), - KUNIT_CASE(krealloc_less_oob), - KUNIT_CASE(krealloc_pagealloc_more_oob), - KUNIT_CASE(krealloc_pagealloc_less_oob), - KUNIT_CASE(krealloc_uaf), - KUNIT_CASE(kmalloc_oob_16), - KUNIT_CASE(kmalloc_uaf_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_memmove_negative_size), - KUNIT_CASE(kmalloc_memmove_invalid_size), - 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(kmem_cache_accounted), - KUNIT_CASE(kmem_cache_bulk), - KUNIT_CASE(kasan_global_oob_right), - KUNIT_CASE(kasan_global_oob_left), - KUNIT_CASE(kasan_stack_oob), - KUNIT_CASE(kasan_alloca_oob_left), - KUNIT_CASE(kasan_alloca_oob_right), - KUNIT_CASE(ksize_unpoisons_memory), - KUNIT_CASE(ksize_uaf), - KUNIT_CASE(kmem_cache_double_free), - KUNIT_CASE(kmem_cache_invalid_free), - KUNIT_CASE(kmem_cache_double_destroy), - KUNIT_CASE(kasan_memchr), - KUNIT_CASE(kasan_memcmp), - KUNIT_CASE(kasan_strings), - KUNIT_CASE(kasan_bitops_generic), - KUNIT_CASE(kasan_bitops_tags), - KUNIT_CASE(kmalloc_double_kzfree), - KUNIT_CASE(vmalloc_helpers_tags), - KUNIT_CASE(vmalloc_oob), - KUNIT_CASE(vmap_tags), - KUNIT_CASE(vm_map_ram_tags), - KUNIT_CASE(vmalloc_percpu), - KUNIT_CASE(match_all_not_assigned), - KUNIT_CASE(match_all_ptr_tag), - KUNIT_CASE(match_all_mem_tag), - {} -}; - -static struct kunit_suite kasan_kunit_test_suite = { - .name = "kasan", - .init = kasan_test_init, - .test_cases = kasan_kunit_test_cases, - .exit = kasan_test_exit, -}; - -kunit_test_suite(kasan_kunit_test_suite); - -MODULE_LICENSE("GPL"); --- a/lib/test_kasan_module.c +++ /dev/null @@ -1,141 +0,0 @@ -// 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> - -#include "../mm/kasan/kasan.h" - -static noinline void __init copy_user_test(void) -{ - char *kmem; - char __user *usermem; - size_t size = 128 - KASAN_GRANULE_SIZE; - int __maybe_unused 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; - } - - OPTIMIZER_HIDE_VAR(size); - - 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 struct kasan_rcu_info { - int i; - struct rcu_head rcu; -} *global_rcu_ptr; - -static noinline void __init kasan_rcu_reclaim(struct rcu_head *rp) -{ - struct kasan_rcu_info *fp = container_of(rp, - struct kasan_rcu_info, rcu); - - kfree(fp); - ((volatile struct kasan_rcu_info *)fp)->i; -} - -static noinline void __init kasan_rcu_uaf(void) -{ - struct kasan_rcu_info *ptr; - - pr_info("use-after-free in kasan_rcu_reclaim\n"); - ptr = kmalloc(sizeof(struct kasan_rcu_info), GFP_KERNEL); - if (!ptr) { - pr_err("Allocation failed\n"); - return; - } - - global_rcu_ptr = rcu_dereference_protected(ptr, NULL); - call_rcu(&global_rcu_ptr->rcu, kasan_rcu_reclaim); -} - -static noinline void __init kasan_workqueue_work(struct work_struct *work) -{ - kfree(work); -} - -static noinline void __init kasan_workqueue_uaf(void) -{ - struct workqueue_struct *workqueue; - struct work_struct *work; - - workqueue = create_workqueue("kasan_wq_test"); - if (!workqueue) { - pr_err("Allocation failed\n"); - return; - } - work = kmalloc(sizeof(struct work_struct), GFP_KERNEL); - if (!work) { - pr_err("Allocation failed\n"); - return; - } - - INIT_WORK(work, kasan_workqueue_work); - queue_work(workqueue, work); - destroy_workqueue(workqueue); - - pr_info("use-after-free on workqueue\n"); - ((volatile struct work_struct *)work)->data; -} - -static int __init test_kasan_module_init(void) -{ - /* - * Temporarily enable multi-shot mode. Otherwise, KASAN would only - * report the first detected bug and panic the kernel if panic_on_warn - * is enabled. - */ - bool multishot = kasan_save_enable_multi_shot(); - - copy_user_test(); - kasan_rcu_uaf(); - kasan_workqueue_uaf(); - - kasan_restore_multi_shot(multishot); - return -EAGAIN; -} - -module_init(test_kasan_module_init); -MODULE_LICENSE("GPL"); --- a/MAINTAINERS~kasan-move-tests-to-mm-kasan +++ a/MAINTAINERS @@ -10938,7 +10938,6 @@ F: arch/*/include/asm/*kasan.h F: arch/*/mm/kasan_init* F: include/linux/kasan*.h F: lib/Kconfig.kasan -F: lib/test_kasan*.c F: mm/kasan/ F: scripts/Makefile.kasan --- /dev/null +++ a/mm/kasan/kasan_test.c @@ -0,0 +1,1426 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * + * Copyright (c) 2014 Samsung Electronics Co., Ltd. + * Author: Andrey Ryabinin <a.ryabinin@xxxxxxxxxxx> + */ + +#include <linux/bitops.h> +#include <linux/delay.h> +#include <linux/kasan.h> +#include <linux/kernel.h> +#include <linux/mm.h> +#include <linux/mman.h> +#include <linux/module.h> +#include <linux/printk.h> +#include <linux/random.h> +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/uaccess.h> +#include <linux/io.h> +#include <linux/vmalloc.h> +#include <linux/set_memory.h> + +#include <asm/page.h> + +#include <kunit/test.h> + +#include "kasan.h" + +#define OOB_TAG_OFF (IS_ENABLED(CONFIG_KASAN_GENERIC) ? 0 : KASAN_GRANULE_SIZE) + +/* + * Some tests use these global variables to store return values from function + * calls that could otherwise be eliminated by the compiler as dead code. + */ +void *kasan_ptr_result; +int kasan_int_result; + +static struct kunit_resource resource; +static struct kunit_kasan_status test_status; +static bool multishot; + +/* + * Temporarily enable multi-shot mode. Otherwise, KASAN would only report the + * first detected bug and panic the kernel if panic_on_warn is enabled. For + * hardware tag-based KASAN also allow tag checking to be reenabled for each + * test, see the comment for KUNIT_EXPECT_KASAN_FAIL(). + */ +static int kasan_test_init(struct kunit *test) +{ + if (!kasan_enabled()) { + kunit_err(test, "can't run KASAN tests with KASAN disabled"); + return -1; + } + + multishot = kasan_save_enable_multi_shot(); + test_status.report_found = false; + test_status.sync_fault = false; + kunit_add_named_resource(test, NULL, NULL, &resource, + "kasan_status", &test_status); + return 0; +} + +static void kasan_test_exit(struct kunit *test) +{ + kasan_restore_multi_shot(multishot); + KUNIT_EXPECT_FALSE(test, test_status.report_found); +} + +/** + * KUNIT_EXPECT_KASAN_FAIL() - check that the executed expression produces a + * KASAN report; causes a test failure otherwise. This relies on a KUnit + * resource named "kasan_status". Do not use this name for KUnit resources + * outside of KASAN tests. + * + * For hardware tag-based KASAN, when a synchronous tag fault happens, tag + * checking is auto-disabled. When this happens, this test handler reenables + * tag checking. As tag checking can be only disabled or enabled per CPU, + * this handler disables migration (preemption). + * + * Since the compiler doesn't see that the expression can change the test_status + * fields, it can reorder or optimize away the accesses to those fields. + * Use READ/WRITE_ONCE() for the accesses and compiler barriers around the + * expression to prevent that. + * + * In between KUNIT_EXPECT_KASAN_FAIL checks, test_status.report_found is kept + * as false. This allows detecting KASAN reports that happen outside of the + * checks by asserting !test_status.report_found at the start of + * KUNIT_EXPECT_KASAN_FAIL and in kasan_test_exit. + */ +#define KUNIT_EXPECT_KASAN_FAIL(test, expression) do { \ + if (IS_ENABLED(CONFIG_KASAN_HW_TAGS) && \ + kasan_sync_fault_possible()) \ + migrate_disable(); \ + KUNIT_EXPECT_FALSE(test, READ_ONCE(test_status.report_found)); \ + barrier(); \ + expression; \ + barrier(); \ + if (kasan_async_fault_possible()) \ + kasan_force_async_fault(); \ + if (!READ_ONCE(test_status.report_found)) { \ + KUNIT_FAIL(test, KUNIT_SUBTEST_INDENT "KASAN failure " \ + "expected in \"" #expression \ + "\", but none occurred"); \ + } \ + if (IS_ENABLED(CONFIG_KASAN_HW_TAGS) && \ + kasan_sync_fault_possible()) { \ + if (READ_ONCE(test_status.report_found) && \ + READ_ONCE(test_status.sync_fault)) \ + kasan_enable_tagging(); \ + migrate_enable(); \ + } \ + WRITE_ONCE(test_status.report_found, false); \ +} while (0) + +#define KASAN_TEST_NEEDS_CONFIG_ON(test, config) do { \ + if (!IS_ENABLED(config)) \ + kunit_skip((test), "Test requires " #config "=y"); \ +} while (0) + +#define KASAN_TEST_NEEDS_CONFIG_OFF(test, config) do { \ + if (IS_ENABLED(config)) \ + kunit_skip((test), "Test requires " #config "=n"); \ +} while (0) + +static void kmalloc_oob_right(struct kunit *test) +{ + char *ptr; + size_t size = 128 - KASAN_GRANULE_SIZE - 5; + + ptr = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + OPTIMIZER_HIDE_VAR(ptr); + /* + * An unaligned access past the requested kmalloc size. + * Only generic KASAN can precisely detect these. + */ + if (IS_ENABLED(CONFIG_KASAN_GENERIC)) + KUNIT_EXPECT_KASAN_FAIL(test, ptr[size] = 'x'); + + /* + * An aligned access into the first out-of-bounds granule that falls + * within the aligned kmalloc object. + */ + KUNIT_EXPECT_KASAN_FAIL(test, ptr[size + 5] = 'y'); + + /* Out-of-bounds access past the aligned kmalloc object. */ + KUNIT_EXPECT_KASAN_FAIL(test, ptr[0] = + ptr[size + KASAN_GRANULE_SIZE + 5]); + + kfree(ptr); +} + +static void kmalloc_oob_left(struct kunit *test) +{ + char *ptr; + size_t size = 15; + + ptr = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + OPTIMIZER_HIDE_VAR(ptr); + KUNIT_EXPECT_KASAN_FAIL(test, *ptr = *(ptr - 1)); + kfree(ptr); +} + +static void kmalloc_node_oob_right(struct kunit *test) +{ + char *ptr; + size_t size = 4096; + + ptr = kmalloc_node(size, GFP_KERNEL, 0); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + OPTIMIZER_HIDE_VAR(ptr); + KUNIT_EXPECT_KASAN_FAIL(test, ptr[0] = ptr[size]); + 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; + size_t size = KMALLOC_MAX_CACHE_SIZE + 10; + + KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_SLUB); + + ptr = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + OPTIMIZER_HIDE_VAR(ptr); + KUNIT_EXPECT_KASAN_FAIL(test, ptr[size + OOB_TAG_OFF] = 0); + + kfree(ptr); +} + +static void kmalloc_pagealloc_uaf(struct kunit *test) +{ + char *ptr; + size_t size = KMALLOC_MAX_CACHE_SIZE + 10; + + KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_SLUB); + + ptr = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + kfree(ptr); + + KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[0]); +} + +static void kmalloc_pagealloc_invalid_free(struct kunit *test) +{ + char *ptr; + size_t size = KMALLOC_MAX_CACHE_SIZE + 10; + + KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_SLUB); + + ptr = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + 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. + */ + KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_GENERIC); + + pages = alloc_pages(GFP_KERNEL, order); + ptr = page_address(pages); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + KUNIT_EXPECT_KASAN_FAIL(test, ptr[0] = ptr[size]); + 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, ((volatile char *)ptr)[0]); +} + +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. + */ + ptr = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + OPTIMIZER_HIDE_VAR(ptr); + KUNIT_EXPECT_KASAN_FAIL(test, ptr[size] = 0); + kfree(ptr); +} + +static void krealloc_more_oob_helper(struct kunit *test, + size_t size1, size_t size2) +{ + char *ptr1, *ptr2; + size_t middle; + + KUNIT_ASSERT_LT(test, size1, size2); + middle = size1 + (size2 - size1) / 2; + + ptr1 = kmalloc(size1, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1); + + ptr2 = krealloc(ptr1, size2, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2); + + /* All offsets up to size2 must be accessible. */ + ptr2[size1 - 1] = 'x'; + ptr2[size1] = 'x'; + ptr2[middle] = 'x'; + ptr2[size2 - 1] = 'x'; + + /* Generic mode is precise, so unaligned size2 must be inaccessible. */ + if (IS_ENABLED(CONFIG_KASAN_GENERIC)) + KUNIT_EXPECT_KASAN_FAIL(test, ptr2[size2] = 'x'); + + /* For all modes first aligned offset after size2 must be inaccessible. */ + KUNIT_EXPECT_KASAN_FAIL(test, + ptr2[round_up(size2, KASAN_GRANULE_SIZE)] = 'x'); + + kfree(ptr2); +} + +static void krealloc_less_oob_helper(struct kunit *test, + size_t size1, size_t size2) +{ + char *ptr1, *ptr2; + size_t middle; + + KUNIT_ASSERT_LT(test, size2, size1); + middle = size2 + (size1 - size2) / 2; + + ptr1 = kmalloc(size1, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1); + + ptr2 = krealloc(ptr1, size2, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2); + + /* Must be accessible for all modes. */ + ptr2[size2 - 1] = 'x'; + + /* Generic mode is precise, so unaligned size2 must be inaccessible. */ + if (IS_ENABLED(CONFIG_KASAN_GENERIC)) + KUNIT_EXPECT_KASAN_FAIL(test, ptr2[size2] = 'x'); + + /* For all modes first aligned offset after size2 must be inaccessible. */ + KUNIT_EXPECT_KASAN_FAIL(test, + ptr2[round_up(size2, KASAN_GRANULE_SIZE)] = 'x'); + + /* + * For all modes all size2, middle, and size1 should land in separate + * granules and thus the latter two offsets should be inaccessible. + */ + KUNIT_EXPECT_LE(test, round_up(size2, KASAN_GRANULE_SIZE), + round_down(middle, KASAN_GRANULE_SIZE)); + KUNIT_EXPECT_LE(test, round_up(middle, KASAN_GRANULE_SIZE), + round_down(size1, KASAN_GRANULE_SIZE)); + KUNIT_EXPECT_KASAN_FAIL(test, ptr2[middle] = 'x'); + KUNIT_EXPECT_KASAN_FAIL(test, ptr2[size1 - 1] = 'x'); + KUNIT_EXPECT_KASAN_FAIL(test, ptr2[size1] = 'x'); + + kfree(ptr2); +} + +static void krealloc_more_oob(struct kunit *test) +{ + krealloc_more_oob_helper(test, 201, 235); +} + +static void krealloc_less_oob(struct kunit *test) +{ + krealloc_less_oob_helper(test, 235, 201); +} + +static void krealloc_pagealloc_more_oob(struct kunit *test) +{ + /* page_alloc fallback in only implemented for SLUB. */ + KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_SLUB); + + krealloc_more_oob_helper(test, KMALLOC_MAX_CACHE_SIZE + 201, + KMALLOC_MAX_CACHE_SIZE + 235); +} + +static void krealloc_pagealloc_less_oob(struct kunit *test) +{ + /* page_alloc fallback in only implemented for SLUB. */ + KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_SLUB); + + krealloc_less_oob_helper(test, KMALLOC_MAX_CACHE_SIZE + 235, + KMALLOC_MAX_CACHE_SIZE + 201); +} + +/* + * Check that krealloc() detects a use-after-free, returns NULL, + * and doesn't unpoison the freed object. + */ +static void krealloc_uaf(struct kunit *test) +{ + char *ptr1, *ptr2; + int size1 = 201; + int size2 = 235; + + ptr1 = kmalloc(size1, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1); + kfree(ptr1); + + KUNIT_EXPECT_KASAN_FAIL(test, ptr2 = krealloc(ptr1, size2, GFP_KERNEL)); + KUNIT_ASSERT_NULL(test, ptr2); + KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)ptr1); +} + +static void kmalloc_oob_16(struct kunit *test) +{ + struct { + u64 words[2]; + } *ptr1, *ptr2; + + /* This test is specifically crafted for the generic mode. */ + KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); + + ptr1 = kmalloc(sizeof(*ptr1) - 3, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1); + + ptr2 = kmalloc(sizeof(*ptr2), GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2); + + OPTIMIZER_HIDE_VAR(ptr1); + OPTIMIZER_HIDE_VAR(ptr2); + KUNIT_EXPECT_KASAN_FAIL(test, *ptr1 = *ptr2); + kfree(ptr1); + kfree(ptr2); +} + +static void kmalloc_uaf_16(struct kunit *test) +{ + struct { + u64 words[2]; + } *ptr1, *ptr2; + + ptr1 = kmalloc(sizeof(*ptr1), GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1); + + ptr2 = kmalloc(sizeof(*ptr2), GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2); + kfree(ptr2); + + KUNIT_EXPECT_KASAN_FAIL(test, *ptr1 = *ptr2); + kfree(ptr1); +} + +/* + * Note: in the memset tests below, the written range touches both valid and + * invalid memory. This makes sure that the instrumentation does not only check + * the starting address but the whole range. + */ + +static void kmalloc_oob_memset_2(struct kunit *test) +{ + char *ptr; + size_t size = 128 - KASAN_GRANULE_SIZE; + + ptr = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + OPTIMIZER_HIDE_VAR(size); + KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr + size - 1, 0, 2)); + kfree(ptr); +} + +static void kmalloc_oob_memset_4(struct kunit *test) +{ + char *ptr; + size_t size = 128 - KASAN_GRANULE_SIZE; + + ptr = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + OPTIMIZER_HIDE_VAR(size); + KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr + size - 3, 0, 4)); + kfree(ptr); +} + +static void kmalloc_oob_memset_8(struct kunit *test) +{ + char *ptr; + size_t size = 128 - KASAN_GRANULE_SIZE; + + ptr = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + OPTIMIZER_HIDE_VAR(size); + KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr + size - 7, 0, 8)); + kfree(ptr); +} + +static void kmalloc_oob_memset_16(struct kunit *test) +{ + char *ptr; + size_t size = 128 - KASAN_GRANULE_SIZE; + + ptr = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + OPTIMIZER_HIDE_VAR(size); + KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr + size - 15, 0, 16)); + kfree(ptr); +} + +static void kmalloc_oob_in_memset(struct kunit *test) +{ + char *ptr; + size_t size = 128 - KASAN_GRANULE_SIZE; + + ptr = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + OPTIMIZER_HIDE_VAR(ptr); + OPTIMIZER_HIDE_VAR(size); + KUNIT_EXPECT_KASAN_FAIL(test, + memset(ptr, 0, size + KASAN_GRANULE_SIZE)); + kfree(ptr); +} + +static void kmalloc_memmove_negative_size(struct kunit *test) +{ + char *ptr; + size_t size = 64; + size_t invalid_size = -2; + + /* + * Hardware tag-based mode doesn't check memmove for negative size. + * As a result, this test introduces a side-effect memory corruption, + * which can result in a crash. + */ + KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_HW_TAGS); + + ptr = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + memset((char *)ptr, 0, 64); + OPTIMIZER_HIDE_VAR(ptr); + OPTIMIZER_HIDE_VAR(invalid_size); + KUNIT_EXPECT_KASAN_FAIL(test, + memmove((char *)ptr, (char *)ptr + 4, invalid_size)); + kfree(ptr); +} + +static void kmalloc_memmove_invalid_size(struct kunit *test) +{ + char *ptr; + size_t size = 64; + volatile size_t invalid_size = size; + + ptr = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + memset((char *)ptr, 0, 64); + OPTIMIZER_HIDE_VAR(ptr); + KUNIT_EXPECT_KASAN_FAIL(test, + memmove((char *)ptr, (char *)ptr + 4, invalid_size)); + kfree(ptr); +} + +static void kmalloc_uaf(struct kunit *test) +{ + char *ptr; + size_t size = 10; + + ptr = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + kfree(ptr); + KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[8]); +} + +static void kmalloc_uaf_memset(struct kunit *test) +{ + char *ptr; + size_t size = 33; + + /* + * Only generic KASAN uses quarantine, which is required to avoid a + * kernel memory corruption this test causes. + */ + KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); + + ptr = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + kfree(ptr); + KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr, 0, size)); +} + +static void kmalloc_uaf2(struct kunit *test) +{ + char *ptr1, *ptr2; + size_t size = 43; + int counter = 0; + +again: + ptr1 = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1); + + kfree(ptr1); + + ptr2 = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr2); + + /* + * For tag-based KASAN ptr1 and ptr2 tags might happen to be the same. + * Allow up to 16 attempts at generating different tags. + */ + if (!IS_ENABLED(CONFIG_KASAN_GENERIC) && ptr1 == ptr2 && counter++ < 16) { + kfree(ptr2); + goto again; + } + + KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr1)[40]); + KUNIT_EXPECT_PTR_NE(test, ptr1, ptr2); + + kfree(ptr2); +} + +static void kfree_via_page(struct kunit *test) +{ + char *ptr; + size_t size = 8; + struct page *page; + unsigned long offset; + + ptr = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + page = virt_to_page(ptr); + offset = offset_in_page(ptr); + kfree(page_address(page) + offset); +} + +static void kfree_via_phys(struct kunit *test) +{ + char *ptr; + size_t size = 8; + phys_addr_t phys; + + ptr = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + phys = virt_to_phys(ptr); + kfree(phys_to_virt(phys)); +} + +static void kmem_cache_oob(struct kunit *test) +{ + char *p; + size_t size = 200; + struct kmem_cache *cache; + + cache = kmem_cache_create("test_cache", size, 0, 0, NULL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache); + + p = kmem_cache_alloc(cache, GFP_KERNEL); + if (!p) { + kunit_err(test, "Allocation failed: %s\n", __func__); + kmem_cache_destroy(cache); + return; + } + + KUNIT_EXPECT_KASAN_FAIL(test, *p = p[size + OOB_TAG_OFF]); + + kmem_cache_free(cache, p); + kmem_cache_destroy(cache); +} + +static void kmem_cache_accounted(struct kunit *test) +{ + int i; + char *p; + size_t size = 200; + struct kmem_cache *cache; + + cache = kmem_cache_create("test_cache", size, 0, SLAB_ACCOUNT, NULL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache); + + /* + * Several allocations with a delay to allow for lazy per memcg kmem + * cache creation. + */ + for (i = 0; i < 5; i++) { + p = kmem_cache_alloc(cache, GFP_KERNEL); + if (!p) + goto free_cache; + + kmem_cache_free(cache, p); + msleep(100); + } + +free_cache: + kmem_cache_destroy(cache); +} + +static void kmem_cache_bulk(struct kunit *test) +{ + struct kmem_cache *cache; + size_t size = 200; + char *p[10]; + bool ret; + int i; + + cache = kmem_cache_create("test_cache", size, 0, 0, NULL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache); + + ret = kmem_cache_alloc_bulk(cache, GFP_KERNEL, ARRAY_SIZE(p), (void **)&p); + if (!ret) { + kunit_err(test, "Allocation failed: %s\n", __func__); + kmem_cache_destroy(cache); + return; + } + + for (i = 0; i < ARRAY_SIZE(p); i++) + p[i][0] = p[i][size - 1] = 42; + + kmem_cache_free_bulk(cache, ARRAY_SIZE(p), (void **)&p); + kmem_cache_destroy(cache); +} + +static char global_array[10]; + +static void kasan_global_oob_right(struct kunit *test) +{ + /* + * Deliberate out-of-bounds access. To prevent CONFIG_UBSAN_LOCAL_BOUNDS + * from failing here and panicking the kernel, access the array via a + * volatile pointer, which will prevent the compiler from being able to + * determine the array bounds. + * + * This access uses a volatile pointer to char (char *volatile) rather + * than the more conventional pointer to volatile char (volatile char *) + * because we want to prevent the compiler from making inferences about + * the pointer itself (i.e. its array bounds), not the data that it + * refers to. + */ + char *volatile array = global_array; + char *p = &array[ARRAY_SIZE(global_array) + 3]; + + /* Only generic mode instruments globals. */ + KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); + + KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p); +} + +static void kasan_global_oob_left(struct kunit *test) +{ + char *volatile array = global_array; + char *p = array - 3; + + /* + * GCC is known to fail this test, skip it. + * See https://bugzilla.kernel.org/show_bug.cgi?id=215051. + */ + KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_CC_IS_CLANG); + KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); + KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p); +} + +/* Check that ksize() makes the whole object accessible. */ +static void ksize_unpoisons_memory(struct kunit *test) +{ + char *ptr; + size_t size = 123, real_size; + + ptr = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + real_size = ksize(ptr); + + OPTIMIZER_HIDE_VAR(ptr); + + /* This access shouldn't trigger a KASAN report. */ + ptr[size] = 'x'; + + /* This one must. */ + KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[real_size]); + + kfree(ptr); +} + +/* + * Check that a use-after-free is detected by ksize() and via normal accesses + * after it. + */ +static void ksize_uaf(struct kunit *test) +{ + char *ptr; + int size = 128 - KASAN_GRANULE_SIZE; + + ptr = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + kfree(ptr); + + OPTIMIZER_HIDE_VAR(ptr); + KUNIT_EXPECT_KASAN_FAIL(test, ksize(ptr)); + KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[0]); + KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr)[size]); +} + +static void kasan_stack_oob(struct kunit *test) +{ + char stack_array[10]; + /* See comment in kasan_global_oob_right. */ + char *volatile array = stack_array; + char *p = &array[ARRAY_SIZE(stack_array) + OOB_TAG_OFF]; + + KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_STACK); + + KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p); +} + +static void kasan_alloca_oob_left(struct kunit *test) +{ + volatile int i = 10; + char alloca_array[i]; + /* See comment in kasan_global_oob_right. */ + char *volatile array = alloca_array; + char *p = array - 1; + + /* Only generic mode instruments dynamic allocas. */ + KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); + KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_STACK); + + KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p); +} + +static void kasan_alloca_oob_right(struct kunit *test) +{ + volatile int i = 10; + char alloca_array[i]; + /* See comment in kasan_global_oob_right. */ + char *volatile array = alloca_array; + char *p = array + i; + + /* Only generic mode instruments dynamic allocas. */ + KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); + KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_STACK); + + KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p); +} + +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); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache); + + p = kmem_cache_alloc(cache, GFP_KERNEL); + if (!p) { + kunit_err(test, "Allocation failed: %s\n", __func__); + kmem_cache_destroy(cache); + return; + } + + kmem_cache_free(cache, p); + KUNIT_EXPECT_KASAN_FAIL(test, kmem_cache_free(cache, p)); + kmem_cache_destroy(cache); +} + +static void kmem_cache_invalid_free(struct kunit *test) +{ + char *p; + size_t size = 200; + struct kmem_cache *cache; + + cache = kmem_cache_create("test_cache", size, 0, SLAB_TYPESAFE_BY_RCU, + NULL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache); + + p = kmem_cache_alloc(cache, GFP_KERNEL); + if (!p) { + kunit_err(test, "Allocation failed: %s\n", __func__); + kmem_cache_destroy(cache); + return; + } + + /* Trigger invalid free, the object doesn't get freed. */ + KUNIT_EXPECT_KASAN_FAIL(test, kmem_cache_free(cache, p + 1)); + + /* + * Properly free the object to prevent the "Objects remaining in + * test_cache on __kmem_cache_shutdown" BUG failure. + */ + kmem_cache_free(cache, p); + + kmem_cache_destroy(cache); +} + +static void empty_cache_ctor(void *object) { } + +static void kmem_cache_double_destroy(struct kunit *test) +{ + struct kmem_cache *cache; + + /* Provide a constructor to prevent cache merging. */ + cache = kmem_cache_create("test_cache", 200, 0, 0, empty_cache_ctor); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, cache); + kmem_cache_destroy(cache); + KUNIT_EXPECT_KASAN_FAIL(test, kmem_cache_destroy(cache)); +} + +static void kasan_memchr(struct kunit *test) +{ + char *ptr; + size_t size = 24; + + /* + * str* functions are not instrumented with CONFIG_AMD_MEM_ENCRYPT. + * See https://bugzilla.kernel.org/show_bug.cgi?id=206337 for details. + */ + KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_AMD_MEM_ENCRYPT); + + if (OOB_TAG_OFF) + size = round_up(size, OOB_TAG_OFF); + + ptr = kmalloc(size, GFP_KERNEL | __GFP_ZERO); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + OPTIMIZER_HIDE_VAR(ptr); + OPTIMIZER_HIDE_VAR(size); + KUNIT_EXPECT_KASAN_FAIL(test, + kasan_ptr_result = memchr(ptr, '1', size + 1)); + + kfree(ptr); +} + +static void kasan_memcmp(struct kunit *test) +{ + char *ptr; + size_t size = 24; + int arr[9]; + + /* + * str* functions are not instrumented with CONFIG_AMD_MEM_ENCRYPT. + * See https://bugzilla.kernel.org/show_bug.cgi?id=206337 for details. + */ + KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_AMD_MEM_ENCRYPT); + + if (OOB_TAG_OFF) + size = round_up(size, OOB_TAG_OFF); + + ptr = kmalloc(size, GFP_KERNEL | __GFP_ZERO); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + memset(arr, 0, sizeof(arr)); + + OPTIMIZER_HIDE_VAR(ptr); + OPTIMIZER_HIDE_VAR(size); + KUNIT_EXPECT_KASAN_FAIL(test, + kasan_int_result = memcmp(ptr, arr, size+1)); + kfree(ptr); +} + +static void kasan_strings(struct kunit *test) +{ + char *ptr; + size_t size = 24; + + /* + * str* functions are not instrumented with CONFIG_AMD_MEM_ENCRYPT. + * See https://bugzilla.kernel.org/show_bug.cgi?id=206337 for details. + */ + KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_AMD_MEM_ENCRYPT); + + ptr = kmalloc(size, GFP_KERNEL | __GFP_ZERO); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + kfree(ptr); + + /* + * Try to cause only 1 invalid access (less spam in dmesg). + * For that we need ptr to point to zeroed byte. + * Skip metadata that could be stored in freed object so ptr + * will likely point to zeroed byte. + */ + ptr += 16; + KUNIT_EXPECT_KASAN_FAIL(test, kasan_ptr_result = strchr(ptr, '1')); + + KUNIT_EXPECT_KASAN_FAIL(test, kasan_ptr_result = strrchr(ptr, '1')); + + KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = strcmp(ptr, "2")); + + KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = strncmp(ptr, "2", 1)); + + KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = strlen(ptr)); + + KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = strnlen(ptr, 1)); +} + +static void kasan_bitops_modify(struct kunit *test, int nr, void *addr) +{ + KUNIT_EXPECT_KASAN_FAIL(test, set_bit(nr, addr)); + KUNIT_EXPECT_KASAN_FAIL(test, __set_bit(nr, addr)); + KUNIT_EXPECT_KASAN_FAIL(test, clear_bit(nr, addr)); + KUNIT_EXPECT_KASAN_FAIL(test, __clear_bit(nr, addr)); + KUNIT_EXPECT_KASAN_FAIL(test, clear_bit_unlock(nr, addr)); + KUNIT_EXPECT_KASAN_FAIL(test, __clear_bit_unlock(nr, addr)); + KUNIT_EXPECT_KASAN_FAIL(test, change_bit(nr, addr)); + KUNIT_EXPECT_KASAN_FAIL(test, __change_bit(nr, addr)); +} + +static void kasan_bitops_test_and_modify(struct kunit *test, int nr, void *addr) +{ + KUNIT_EXPECT_KASAN_FAIL(test, test_and_set_bit(nr, addr)); + KUNIT_EXPECT_KASAN_FAIL(test, __test_and_set_bit(nr, addr)); + KUNIT_EXPECT_KASAN_FAIL(test, test_and_set_bit_lock(nr, addr)); + KUNIT_EXPECT_KASAN_FAIL(test, test_and_clear_bit(nr, addr)); + KUNIT_EXPECT_KASAN_FAIL(test, __test_and_clear_bit(nr, addr)); + KUNIT_EXPECT_KASAN_FAIL(test, test_and_change_bit(nr, addr)); + KUNIT_EXPECT_KASAN_FAIL(test, __test_and_change_bit(nr, addr)); + KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = test_bit(nr, addr)); + +#if defined(clear_bit_unlock_is_negative_byte) + KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = + clear_bit_unlock_is_negative_byte(nr, addr)); +#endif +} + +static void kasan_bitops_generic(struct kunit *test) +{ + long *bits; + + /* This test is specifically crafted for the generic mode. */ + KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC); + + /* + * Allocate 1 more byte, which causes kzalloc to round up to 16 bytes; + * this way we do not actually corrupt other memory. + */ + bits = kzalloc(sizeof(*bits) + 1, GFP_KERNEL); + 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. + */ + kasan_bitops_modify(test, BITS_PER_LONG, bits); + + /* + * Below calls try to access bit beyond allocated memory. + */ + kasan_bitops_test_and_modify(test, BITS_PER_LONG + BITS_PER_BYTE, bits); + + kfree(bits); +} + +static void kasan_bitops_tags(struct kunit *test) +{ + long *bits; + + /* This test is specifically crafted for tag-based modes. */ + KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_GENERIC); + + /* kmalloc-64 cache will be used and the last 16 bytes will be the redzone. */ + bits = kzalloc(48, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, bits); + + /* Do the accesses past the 48 allocated bytes, but within the redone. */ + kasan_bitops_modify(test, BITS_PER_LONG, (void *)bits + 48); + kasan_bitops_test_and_modify(test, BITS_PER_LONG + BITS_PER_BYTE, (void *)bits + 48); + + kfree(bits); +} + +static void kmalloc_double_kzfree(struct kunit *test) +{ + char *ptr; + size_t size = 16; + + ptr = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + kfree_sensitive(ptr); + KUNIT_EXPECT_KASAN_FAIL(test, kfree_sensitive(ptr)); +} + +static void vmalloc_helpers_tags(struct kunit *test) +{ + void *ptr; + + /* This test is intended for tag-based modes. */ + KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_GENERIC); + + KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_VMALLOC); + + ptr = vmalloc(PAGE_SIZE); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + /* Check that the returned pointer is tagged. */ + KUNIT_EXPECT_GE(test, (u8)get_tag(ptr), (u8)KASAN_TAG_MIN); + KUNIT_EXPECT_LT(test, (u8)get_tag(ptr), (u8)KASAN_TAG_KERNEL); + + /* Make sure exported vmalloc helpers handle tagged pointers. */ + KUNIT_ASSERT_TRUE(test, is_vmalloc_addr(ptr)); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, vmalloc_to_page(ptr)); + +#if !IS_MODULE(CONFIG_KASAN_KUNIT_TEST) + { + int rv; + + /* Make sure vmalloc'ed memory permissions can be changed. */ + rv = set_memory_ro((unsigned long)ptr, 1); + KUNIT_ASSERT_GE(test, rv, 0); + rv = set_memory_rw((unsigned long)ptr, 1); + KUNIT_ASSERT_GE(test, rv, 0); + } +#endif + + vfree(ptr); +} + +static void vmalloc_oob(struct kunit *test) +{ + char *v_ptr, *p_ptr; + struct page *page; + size_t size = PAGE_SIZE / 2 - KASAN_GRANULE_SIZE - 5; + + KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_VMALLOC); + + v_ptr = vmalloc(size); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, v_ptr); + + OPTIMIZER_HIDE_VAR(v_ptr); + + /* + * We have to be careful not to hit the guard page in vmalloc tests. + * The MMU will catch that and crash us. + */ + + /* Make sure in-bounds accesses are valid. */ + v_ptr[0] = 0; + v_ptr[size - 1] = 0; + + /* + * An unaligned access past the requested vmalloc size. + * Only generic KASAN can precisely detect these. + */ + if (IS_ENABLED(CONFIG_KASAN_GENERIC)) + KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)v_ptr)[size]); + + /* An aligned access into the first out-of-bounds granule. */ + KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)v_ptr)[size + 5]); + + /* Check that in-bounds accesses to the physical page are valid. */ + page = vmalloc_to_page(v_ptr); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, page); + p_ptr = page_address(page); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, p_ptr); + p_ptr[0] = 0; + + vfree(v_ptr); + + /* + * We can't check for use-after-unmap bugs in this nor in the following + * vmalloc tests, as the page might be fully unmapped and accessing it + * will crash the kernel. + */ +} + +static void vmap_tags(struct kunit *test) +{ + char *p_ptr, *v_ptr; + struct page *p_page, *v_page; + + /* + * This test is specifically crafted for the software tag-based mode, + * the only tag-based mode that poisons vmap mappings. + */ + KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_SW_TAGS); + + KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_VMALLOC); + + p_page = alloc_pages(GFP_KERNEL, 1); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, p_page); + p_ptr = page_address(p_page); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, p_ptr); + + v_ptr = vmap(&p_page, 1, VM_MAP, PAGE_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, v_ptr); + + /* + * We can't check for out-of-bounds bugs in this nor in the following + * vmalloc tests, as allocations have page granularity and accessing + * the guard page will crash the kernel. + */ + + KUNIT_EXPECT_GE(test, (u8)get_tag(v_ptr), (u8)KASAN_TAG_MIN); + KUNIT_EXPECT_LT(test, (u8)get_tag(v_ptr), (u8)KASAN_TAG_KERNEL); + + /* Make sure that in-bounds accesses through both pointers work. */ + *p_ptr = 0; + *v_ptr = 0; + + /* Make sure vmalloc_to_page() correctly recovers the page pointer. */ + v_page = vmalloc_to_page(v_ptr); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, v_page); + KUNIT_EXPECT_PTR_EQ(test, p_page, v_page); + + vunmap(v_ptr); + free_pages((unsigned long)p_ptr, 1); +} + +static void vm_map_ram_tags(struct kunit *test) +{ + char *p_ptr, *v_ptr; + struct page *page; + + /* + * This test is specifically crafted for the software tag-based mode, + * the only tag-based mode that poisons vm_map_ram mappings. + */ + KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_SW_TAGS); + + page = alloc_pages(GFP_KERNEL, 1); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, page); + p_ptr = page_address(page); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, p_ptr); + + v_ptr = vm_map_ram(&page, 1, -1); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, v_ptr); + + KUNIT_EXPECT_GE(test, (u8)get_tag(v_ptr), (u8)KASAN_TAG_MIN); + KUNIT_EXPECT_LT(test, (u8)get_tag(v_ptr), (u8)KASAN_TAG_KERNEL); + + /* Make sure that in-bounds accesses through both pointers work. */ + *p_ptr = 0; + *v_ptr = 0; + + vm_unmap_ram(v_ptr, 1); + free_pages((unsigned long)p_ptr, 1); +} + +static void vmalloc_percpu(struct kunit *test) +{ + char __percpu *ptr; + int cpu; + + /* + * This test is specifically crafted for the software tag-based mode, + * the only tag-based mode that poisons percpu mappings. + */ + KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_SW_TAGS); + + ptr = __alloc_percpu(PAGE_SIZE, PAGE_SIZE); + + for_each_possible_cpu(cpu) { + char *c_ptr = per_cpu_ptr(ptr, cpu); + + KUNIT_EXPECT_GE(test, (u8)get_tag(c_ptr), (u8)KASAN_TAG_MIN); + KUNIT_EXPECT_LT(test, (u8)get_tag(c_ptr), (u8)KASAN_TAG_KERNEL); + + /* Make sure that in-bounds accesses don't crash the kernel. */ + *c_ptr = 0; + } + + free_percpu(ptr); +} + +/* + * Check that the assigned pointer tag falls within the [KASAN_TAG_MIN, + * KASAN_TAG_KERNEL) range (note: excluding the match-all tag) for tag-based + * modes. + */ +static void match_all_not_assigned(struct kunit *test) +{ + char *ptr; + struct page *pages; + int i, size, order; + + KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_GENERIC); + + for (i = 0; i < 256; i++) { + size = (get_random_int() % 1024) + 1; + ptr = kmalloc(size, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + KUNIT_EXPECT_GE(test, (u8)get_tag(ptr), (u8)KASAN_TAG_MIN); + KUNIT_EXPECT_LT(test, (u8)get_tag(ptr), (u8)KASAN_TAG_KERNEL); + kfree(ptr); + } + + for (i = 0; i < 256; i++) { + order = (get_random_int() % 4) + 1; + pages = alloc_pages(GFP_KERNEL, order); + ptr = page_address(pages); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + KUNIT_EXPECT_GE(test, (u8)get_tag(ptr), (u8)KASAN_TAG_MIN); + KUNIT_EXPECT_LT(test, (u8)get_tag(ptr), (u8)KASAN_TAG_KERNEL); + free_pages((unsigned long)ptr, order); + } + + if (!IS_ENABLED(CONFIG_KASAN_VMALLOC)) + return; + + for (i = 0; i < 256; i++) { + size = (get_random_int() % 1024) + 1; + ptr = vmalloc(size); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + KUNIT_EXPECT_GE(test, (u8)get_tag(ptr), (u8)KASAN_TAG_MIN); + KUNIT_EXPECT_LT(test, (u8)get_tag(ptr), (u8)KASAN_TAG_KERNEL); + vfree(ptr); + } +} + +/* Check that 0xff works as a match-all pointer tag for tag-based modes. */ +static void match_all_ptr_tag(struct kunit *test) +{ + char *ptr; + u8 tag; + + KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_GENERIC); + + ptr = kmalloc(128, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + + /* Backup the assigned tag. */ + tag = get_tag(ptr); + KUNIT_EXPECT_NE(test, tag, (u8)KASAN_TAG_KERNEL); + + /* Reset the tag to 0xff.*/ + ptr = set_tag(ptr, KASAN_TAG_KERNEL); + + /* This access shouldn't trigger a KASAN report. */ + *ptr = 0; + + /* Recover the pointer tag and free. */ + ptr = set_tag(ptr, tag); + kfree(ptr); +} + +/* Check that there are no match-all memory tags for tag-based modes. */ +static void match_all_mem_tag(struct kunit *test) +{ + char *ptr; + int tag; + + KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_GENERIC); + + ptr = kmalloc(128, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr); + KUNIT_EXPECT_NE(test, (u8)get_tag(ptr), (u8)KASAN_TAG_KERNEL); + + /* For each possible tag value not matching the pointer tag. */ + for (tag = KASAN_TAG_MIN; tag <= KASAN_TAG_KERNEL; tag++) { + if (tag == get_tag(ptr)) + continue; + + /* Mark the first memory granule with the chosen memory tag. */ + kasan_poison(ptr, KASAN_GRANULE_SIZE, (u8)tag, false); + + /* This access must cause a KASAN report. */ + KUNIT_EXPECT_KASAN_FAIL(test, *ptr = 0); + } + + /* Recover the memory tag and free. */ + kasan_poison(ptr, KASAN_GRANULE_SIZE, get_tag(ptr), false); + kfree(ptr); +} + +static struct kunit_case kasan_kunit_test_cases[] = { + KUNIT_CASE(kmalloc_oob_right), + KUNIT_CASE(kmalloc_oob_left), + KUNIT_CASE(kmalloc_node_oob_right), + 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(krealloc_more_oob), + KUNIT_CASE(krealloc_less_oob), + KUNIT_CASE(krealloc_pagealloc_more_oob), + KUNIT_CASE(krealloc_pagealloc_less_oob), + KUNIT_CASE(krealloc_uaf), + KUNIT_CASE(kmalloc_oob_16), + KUNIT_CASE(kmalloc_uaf_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_memmove_negative_size), + KUNIT_CASE(kmalloc_memmove_invalid_size), + 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(kmem_cache_accounted), + KUNIT_CASE(kmem_cache_bulk), + KUNIT_CASE(kasan_global_oob_right), + KUNIT_CASE(kasan_global_oob_left), + KUNIT_CASE(kasan_stack_oob), + KUNIT_CASE(kasan_alloca_oob_left), + KUNIT_CASE(kasan_alloca_oob_right), + KUNIT_CASE(ksize_unpoisons_memory), + KUNIT_CASE(ksize_uaf), + KUNIT_CASE(kmem_cache_double_free), + KUNIT_CASE(kmem_cache_invalid_free), + KUNIT_CASE(kmem_cache_double_destroy), + KUNIT_CASE(kasan_memchr), + KUNIT_CASE(kasan_memcmp), + KUNIT_CASE(kasan_strings), + KUNIT_CASE(kasan_bitops_generic), + KUNIT_CASE(kasan_bitops_tags), + KUNIT_CASE(kmalloc_double_kzfree), + KUNIT_CASE(vmalloc_helpers_tags), + KUNIT_CASE(vmalloc_oob), + KUNIT_CASE(vmap_tags), + KUNIT_CASE(vm_map_ram_tags), + KUNIT_CASE(vmalloc_percpu), + KUNIT_CASE(match_all_not_assigned), + KUNIT_CASE(match_all_ptr_tag), + KUNIT_CASE(match_all_mem_tag), + {} +}; + +static struct kunit_suite kasan_kunit_test_suite = { + .name = "kasan", + .init = kasan_test_init, + .test_cases = kasan_kunit_test_cases, + .exit = kasan_test_exit, +}; + +kunit_test_suite(kasan_kunit_test_suite); + +MODULE_LICENSE("GPL"); --- /dev/null +++ a/mm/kasan/kasan_test_module.c @@ -0,0 +1,141 @@ +// 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> + +#include "kasan.h" + +static noinline void __init copy_user_test(void) +{ + char *kmem; + char __user *usermem; + size_t size = 128 - KASAN_GRANULE_SIZE; + int __maybe_unused 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; + } + + OPTIMIZER_HIDE_VAR(size); + + 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 struct kasan_rcu_info { + int i; + struct rcu_head rcu; +} *global_rcu_ptr; + +static noinline void __init kasan_rcu_reclaim(struct rcu_head *rp) +{ + struct kasan_rcu_info *fp = container_of(rp, + struct kasan_rcu_info, rcu); + + kfree(fp); + ((volatile struct kasan_rcu_info *)fp)->i; +} + +static noinline void __init kasan_rcu_uaf(void) +{ + struct kasan_rcu_info *ptr; + + pr_info("use-after-free in kasan_rcu_reclaim\n"); + ptr = kmalloc(sizeof(struct kasan_rcu_info), GFP_KERNEL); + if (!ptr) { + pr_err("Allocation failed\n"); + return; + } + + global_rcu_ptr = rcu_dereference_protected(ptr, NULL); + call_rcu(&global_rcu_ptr->rcu, kasan_rcu_reclaim); +} + +static noinline void __init kasan_workqueue_work(struct work_struct *work) +{ + kfree(work); +} + +static noinline void __init kasan_workqueue_uaf(void) +{ + struct workqueue_struct *workqueue; + struct work_struct *work; + + workqueue = create_workqueue("kasan_wq_test"); + if (!workqueue) { + pr_err("Allocation failed\n"); + return; + } + work = kmalloc(sizeof(struct work_struct), GFP_KERNEL); + if (!work) { + pr_err("Allocation failed\n"); + return; + } + + INIT_WORK(work, kasan_workqueue_work); + queue_work(workqueue, work); + destroy_workqueue(workqueue); + + pr_info("use-after-free on workqueue\n"); + ((volatile struct work_struct *)work)->data; +} + +static int __init test_kasan_module_init(void) +{ + /* + * Temporarily enable multi-shot mode. Otherwise, KASAN would only + * report the first detected bug and panic the kernel if panic_on_warn + * is enabled. + */ + bool multishot = kasan_save_enable_multi_shot(); + + copy_user_test(); + kasan_rcu_uaf(); + kasan_workqueue_uaf(); + + kasan_restore_multi_shot(multishot); + return -EAGAIN; +} + +module_init(test_kasan_module_init); +MODULE_LICENSE("GPL"); --- a/mm/kasan/Makefile~kasan-move-tests-to-mm-kasan +++ a/mm/kasan/Makefile @@ -35,7 +35,15 @@ CFLAGS_shadow.o := $(CC_FLAGS_KASAN_RUNT CFLAGS_hw_tags.o := $(CC_FLAGS_KASAN_RUNTIME) CFLAGS_sw_tags.o := $(CC_FLAGS_KASAN_RUNTIME) +CFLAGS_KASAN_TEST := $(CFLAGS_KASAN) -fno-builtin $(call cc-disable-warning, vla) + +CFLAGS_kasan_test.o := $(CFLAGS_KASAN_TEST) +CFLAGS_kasan_test_module.o := $(CFLAGS_KASAN_TEST) + obj-y := common.o report.o obj-$(CONFIG_KASAN_GENERIC) += init.o generic.o report_generic.o shadow.o quarantine.o obj-$(CONFIG_KASAN_HW_TAGS) += hw_tags.o report_hw_tags.o tags.o report_tags.o obj-$(CONFIG_KASAN_SW_TAGS) += init.o report_sw_tags.o shadow.o sw_tags.o tags.o report_tags.o + +obj-$(CONFIG_KASAN_KUNIT_TEST) += kasan_test.o +obj-$(CONFIG_KASAN_MODULE_TEST) += kasan_test_module.o _ Patches currently in -mm which might be from andreyknvl@xxxxxxxxxx are kasan-move-tests-to-mm-kasan.patch