kernel_optimize_test/lib/test_kasan.c
Andrey Konovalov 58b999d7a2 kasan: adopt KUNIT tests to SW_TAGS mode
Now that we have KASAN-KUNIT tests integration, it's easy to see that
some KASAN tests are not adopted to the SW_TAGS mode and are failing.

Adjust the allocation size for kasan_memchr() and kasan_memcmp() by
roung it up to OOB_TAG_OFF so the bad access ends up in a separate
memory granule.

Add a new kmalloc_uaf_16() tests that relies on UAF, and a new
kasan_bitops_tags() test that is tailored to tag-based mode, as it's
hard to adopt the existing kmalloc_oob_16() and kasan_bitops_generic()
(renamed from kasan_bitops()) without losing the precision.

Add new kmalloc_uaf_16() and kasan_bitops_uaf() tests that rely on UAFs,
as it's hard to adopt the existing kmalloc_oob_16() and
kasan_bitops_oob() (rename from kasan_bitops()) without losing the
precision.

Disable kasan_global_oob() and kasan_alloca_oob_left/right() as SW_TAGS
mode doesn't instrument globals nor dynamic allocas.

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: David Gow <davidgow@google.com>
Link: https://lkml.kernel.org/r/76eee17b6531ca8b3ca92b240cb2fd23204aaff7.1603129942.git.andreyknvl@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-11-02 12:14:18 -08:00

835 lines
20 KiB
C

// 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/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_SHADOW_SCALE_SIZE)
/*
* We assign some test results to these globals to make sure the tests
* are not eliminated 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;
static int kasan_test_init(struct kunit *test)
{
/*
* Temporarily enable multi-shot mode and set panic_on_warn=0.
* Otherwise, we'd only get a report for the first case.
*/
multishot = kasan_save_enable_multi_shot();
return 0;
}
static void kasan_test_exit(struct kunit *test)
{
kasan_restore_multi_shot(multishot);
}
/**
* KUNIT_EXPECT_KASAN_FAIL() - Causes a test failure when the expression does
* not cause a KASAN error. This uses a KUnit resource named "kasan_data." Do
* Do not use this name for a KUnit resource outside here.
*
*/
#define KUNIT_EXPECT_KASAN_FAIL(test, condition) do { \
fail_data.report_expected = true; \
fail_data.report_found = false; \
kunit_add_named_resource(test, \
NULL, \
NULL, \
&resource, \
"kasan_data", &fail_data); \
condition; \
KUNIT_EXPECT_EQ(test, \
fail_data.report_expected, \
fail_data.report_found); \
} 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);
}
static void kmalloc_pagealloc_oob_right(struct kunit *test)
{
char *ptr;
size_t size = KMALLOC_MAX_CACHE_SIZE + 10;
if (!IS_ENABLED(CONFIG_SLUB)) {
kunit_info(test, "CONFIG_SLUB is not enabled.");
return;
}
/* Allocate a chunk that does not fit into a SLUB cache to trigger
* the page allocator fallback.
*/
ptr = kmalloc(size, GFP_KERNEL);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
KUNIT_EXPECT_KASAN_FAIL(test, ptr[size + OOB_TAG_OFF] = 0);
kfree(ptr);
}
static void kmalloc_pagealloc_uaf(struct kunit *test)
{
char *ptr;
size_t size = KMALLOC_MAX_CACHE_SIZE + 10;
if (!IS_ENABLED(CONFIG_SLUB)) {
kunit_info(test, "CONFIG_SLUB is not enabled.");
return;
}
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;
if (!IS_ENABLED(CONFIG_SLUB)) {
kunit_info(test, "CONFIG_SLUB is not enabled.");
return;
}
ptr = kmalloc(size, GFP_KERNEL);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
KUNIT_EXPECT_KASAN_FAIL(test, kfree(ptr + 1));
}
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 kmalloc_oob_krealloc_more(struct kunit *test)
{
char *ptr1, *ptr2;
size_t size1 = 17;
size_t size2 = 19;
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);
KUNIT_EXPECT_KASAN_FAIL(test, ptr2[size2 + OOB_TAG_OFF] = 'x');
kfree(ptr2);
}
static void kmalloc_oob_krealloc_less(struct kunit *test)
{
char *ptr1, *ptr2;
size_t size1 = 17;
size_t size2 = 15;
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);
KUNIT_EXPECT_KASAN_FAIL(test, ptr2[size2 + OOB_TAG_OFF] = 'x');
kfree(ptr2);
}
static void kmalloc_oob_16(struct kunit *test)
{
struct {
u64 words[2];
} *ptr1, *ptr2;
/* This test is specifically crafted for the generic mode. */
if (!IS_ENABLED(CONFIG_KASAN_GENERIC)) {
kunit_info(test, "CONFIG_KASAN_GENERIC required\n");
return;
}
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;
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);
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 = 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 memcg_accounted_kmem_cache(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 char global_array[10];
static void kasan_global_oob(struct kunit *test)
{
volatile int i = 3;
char *p = &global_array[ARRAY_SIZE(global_array) + i];
/* Only generic mode instruments globals. */
if (!IS_ENABLED(CONFIG_KASAN_GENERIC)) {
kunit_info(test, "CONFIG_KASAN_GENERIC required");
return;
}
KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p);
}
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 doesn't trigger an error. */
ptr[size] = 'x';
/* This one does. */
KUNIT_EXPECT_KASAN_FAIL(test, ptr[real_size] = 'y');
kfree(ptr);
}
static void kasan_stack_oob(struct kunit *test)
{
char stack_array[10];
volatile int i = OOB_TAG_OFF;
char *p = &stack_array[ARRAY_SIZE(stack_array) + i];
if (!IS_ENABLED(CONFIG_KASAN_STACK)) {
kunit_info(test, "CONFIG_KASAN_STACK is not enabled");
return;
}
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];
char *p = alloca_array - 1;
/* Only generic mode instruments dynamic allocas. */
if (!IS_ENABLED(CONFIG_KASAN_GENERIC)) {
kunit_info(test, "CONFIG_KASAN_GENERIC required");
return;
}
if (!IS_ENABLED(CONFIG_KASAN_STACK)) {
kunit_info(test, "CONFIG_KASAN_STACK is not enabled");
return;
}
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];
char *p = alloca_array + i;
/* Only generic mode instruments dynamic allocas. */
if (!IS_ENABLED(CONFIG_KASAN_GENERIC)) {
kunit_info(test, "CONFIG_KASAN_GENERIC required");
return;
}
if (!IS_ENABLED(CONFIG_KASAN_STACK)) {
kunit_info(test, "CONFIG_KASAN_STACK is not enabled");
return;
}
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;
/* See https://bugzilla.kernel.org/show_bug.cgi?id=206337 */
if (IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT)) {
kunit_info(test,
"str* functions are not instrumented with CONFIG_AMD_MEM_ENCRYPT");
return;
}
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];
/* See https://bugzilla.kernel.org/show_bug.cgi?id=206337 */
if (IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT)) {
kunit_info(test,
"str* functions are not instrumented with CONFIG_AMD_MEM_ENCRYPT");
return;
}
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;
/* See https://bugzilla.kernel.org/show_bug.cgi?id=206337 */
if (IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT)) {
kunit_info(test,
"str* functions are not instrumented with CONFIG_AMD_MEM_ENCRYPT");
return;
}
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. */
if (!IS_ENABLED(CONFIG_KASAN_GENERIC)) {
kunit_info(test, "CONFIG_KASAN_GENERIC required\n");
return;
}
/*
* 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 the tag-based mode. */
if (IS_ENABLED(CONFIG_KASAN_GENERIC)) {
kunit_info(test, "CONFIG_KASAN_SW_TAGS required\n");
return;
}
/* Allocation size will be rounded to up granule size, which is 16. */
bits = kzalloc(sizeof(*bits), GFP_KERNEL);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, bits);
/* Do the accesses past the 16 allocated bytes. */
kasan_bitops_modify(test, BITS_PER_LONG, &bits[1]);
kasan_bitops_test_and_modify(test, BITS_PER_LONG + BITS_PER_BYTE, &bits[1]);
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;
if (!IS_ENABLED(CONFIG_KASAN_VMALLOC)) {
kunit_info(test, "CONFIG_KASAN_VMALLOC is not enabled.");
return;
}
/*
* 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);
}
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(kmalloc_large_oob_right),
KUNIT_CASE(kmalloc_oob_krealloc_more),
KUNIT_CASE(kmalloc_oob_krealloc_less),
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(memcg_accounted_kmem_cache),
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(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),
{}
};
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");