kasan: move tests to mm/kasan/

Move KASAN tests to mm/kasan/ to keep the test code alongside the
implementation.

Link: https://lkml.kernel.org/r/676398f0aeecd47d2f8e3369ea0e95563f641a36.1662416260.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

3 files changed, 1599 insertions, 0 deletions

diff --git a/mm/kasan/Makefile b/mm/kasan/Makefile
index 1f84df9c302e..d4837bff3b60 100644
--- a/mm/kasan/Makefile
+++ b/mm/kasan/Makefile
@@ -35,7 +35,15 @@ CFLAGS_shadow.o := $(CC_FLAGS_KASAN_RUNTIME)
 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
diff --git a/mm/kasan/kasan_test.c b/mm/kasan/kasan_test.c
new file mode 100644
index 000000000000..f25692def781
--- /dev/null
+++ b/mm/kasan/kasan_test.c
@@ -0,0 +1,1450 @@
+// 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 <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);
+}
+
+/*
+ * Check that KASAN detects use-after-free when another object was allocated in
+ * the same slot. Relevant for the tag-based modes, which do not use quarantine.
+ */
+static void kmalloc_uaf3(struct kunit *test)
+{
+	char *ptr1, *ptr2;
+	size_t size = 100;
+
+	/* This test is specifically crafted for tag-based modes. */
+	KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_GENERIC);
+
+	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);
+	kfree(ptr2);
+
+	KUNIT_EXPECT_KASAN_FAIL(test, ((volatile char *)ptr1)[8]);
+}
+
+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(kmalloc_uaf3),
+	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");
diff --git a/mm/kasan/kasan_test_module.c b/mm/kasan/kasan_test_module.c
new file mode 100644
index 000000000000..e4ca82dc2c16
--- /dev/null
+++ b/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@samsung.com>
+ */
+
+#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");