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- // SPDX-License-Identifier: GPL-2.0-only
- /*
- *
- * Copyright (c) 2014 Samsung Electronics Co., Ltd.
- * Author: Andrey Ryabinin <a.ryabinin@samsung.com>
- */
- #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 <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_expectation fail_data;
- 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();
- kasan_set_tagging_report_once(false);
- return 0;
- }
- static void kasan_test_exit(struct kunit *test)
- {
- kasan_set_tagging_report_once(true);
- kasan_restore_multi_shot(multishot);
- }
- /**
- * 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_data". Do not use this name for KUnit resources
- * outside of KASAN tests.
- *
- * For hardware tag-based KASAN in sync mode, when a 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 fail_data
- * 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.
- */
- #define KUNIT_EXPECT_KASAN_FAIL(test, expression) do { \
- if (IS_ENABLED(CONFIG_KASAN_HW_TAGS) && \
- !kasan_async_mode_enabled()) \
- migrate_disable(); \
- WRITE_ONCE(fail_data.report_expected, true); \
- WRITE_ONCE(fail_data.report_found, false); \
- kunit_add_named_resource(test, \
- NULL, \
- NULL, \
- &resource, \
- "kasan_data", &fail_data); \
- barrier(); \
- expression; \
- barrier(); \
- if (kasan_async_mode_enabled()) \
- kasan_force_async_fault(); \
- barrier(); \
- KUNIT_EXPECT_EQ(test, \
- READ_ONCE(fail_data.report_expected), \
- READ_ONCE(fail_data.report_found)); \
- if (IS_ENABLED(CONFIG_KASAN_HW_TAGS) && \
- !kasan_async_mode_enabled()) { \
- if (READ_ONCE(fail_data.report_found)) \
- kasan_enable_tagging_sync(); \
- migrate_enable(); \
- } \
- } while (0)
- #define KASAN_TEST_NEEDS_CONFIG_ON(test, config) do { \
- if (!IS_ENABLED(config)) { \
- kunit_info((test), "skipping, " #config " required"); \
- return; \
- } \
- } while (0)
- #define KASAN_TEST_NEEDS_CONFIG_OFF(test, config) do { \
- if (IS_ENABLED(config)) { \
- kunit_info((test), "skipping, " #config " enabled"); \
- return; \
- } \
- } while (0)
- static void kmalloc_oob_right(struct kunit *test)
- {
- char *ptr;
- size_t size = 123;
- ptr = kmalloc(size, GFP_KERNEL);
- KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
- KUNIT_EXPECT_KASAN_FAIL(test, ptr[size + OOB_TAG_OFF] = 'x');
- 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);
- 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);
- KUNIT_EXPECT_KASAN_FAIL(test, ptr[size] = 0);
- 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);
- 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, ptr[0] = 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[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;
- 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);
- 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_PTR_EQ(test, (void *)ptr2, NULL);
- 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);
- 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);
- }
- static void kmalloc_oob_memset_2(struct kunit *test)
- {
- char *ptr;
- size_t size = 8;
- ptr = kmalloc(size, GFP_KERNEL);
- KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
- KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr + 7 + OOB_TAG_OFF, 0, 2));
- kfree(ptr);
- }
- static void kmalloc_oob_memset_4(struct kunit *test)
- {
- char *ptr;
- size_t size = 8;
- ptr = kmalloc(size, GFP_KERNEL);
- KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
- KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr + 5 + OOB_TAG_OFF, 0, 4));
- kfree(ptr);
- }
- static void kmalloc_oob_memset_8(struct kunit *test)
- {
- char *ptr;
- size_t size = 8;
- ptr = kmalloc(size, GFP_KERNEL);
- KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
- KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr + 1 + OOB_TAG_OFF, 0, 8));
- kfree(ptr);
- }
- static void kmalloc_oob_memset_16(struct kunit *test)
- {
- char *ptr;
- size_t size = 16;
- ptr = kmalloc(size, GFP_KERNEL);
- KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
- KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr + 1 + OOB_TAG_OFF, 0, 16));
- kfree(ptr);
- }
- static void kmalloc_oob_in_memset(struct kunit *test)
- {
- char *ptr;
- size_t size = 666;
- ptr = kmalloc(size, GFP_KERNEL);
- KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
- KUNIT_EXPECT_KASAN_FAIL(test, memset(ptr, 0, size + 5 + OOB_TAG_OFF));
- kfree(ptr);
- }
- static void kmalloc_memmove_invalid_size(struct kunit *test)
- {
- char *ptr;
- size_t size = 64;
- volatile size_t invalid_size = -2;
- ptr = kmalloc(size, GFP_KERNEL);
- KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
- memset((char *)ptr, 0, 64);
- 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, *(ptr + 8) = 'x');
- }
- static void kmalloc_uaf_memset(struct kunit *test)
- {
- char *ptr;
- size_t size = 33;
- 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, ptr1[40] = 'x');
- 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(struct kunit *test)
- {
- /*
- * Deliberate out-of-bounds access. To prevent CONFIG_UBSAN_LOCAL_BOUNDS
- * from failing here and panicing 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);
- }
- /* 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);
- /* This access shouldn't trigger a KASAN report. */
- ptr[size] = 'x';
- /* This one must. */
- KUNIT_EXPECT_KASAN_FAIL(test, ptr[real_size] = 'y');
- 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);
- KUNIT_EXPECT_KASAN_FAIL(test, ksize(ptr));
- KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = *ptr);
- KUNIT_EXPECT_KASAN_FAIL(test, kasan_int_result = *(ptr + size));
- }
- static void kasan_stack_oob(struct kunit *test)
- {
- char stack_array[10];
- /* See comment in kasan_global_oob. */
- 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. */
- 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. */
- 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 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);
- 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));
- 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_oob(struct kunit *test)
- {
- void *area;
- KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_VMALLOC);
- /*
- * We have to be careful not to hit the guard page.
- * The MMU will catch that and crash us.
- */
- area = vmalloc(3000);
- KUNIT_ASSERT_NOT_ERR_OR_NULL(test, area);
- KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)area)[3100]);
- vfree(area);
- }
- /*
- * 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);
- }
- }
- /* 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_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),
- 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(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_oob),
- 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");
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