Re: [RFC PATCH 1/2] Port KASAN Tests to KUnit
From: Dmitry Vyukov
Date: Thu Feb 27 2020 - 09:19:43 EST
.On Thu, Feb 27, 2020 at 3:44 AM Patricia Alfonso
<trishalfonso@xxxxxxxxxx> wrote:
>
> Transfer all previous tests for KASAN to KUnit so they can be run
> more easily. With proper KASAN integration into KUnit, developers can
> run these tests with their other KUnit tests and see "pass" or "fail"
> with the appropriate KASAN report instead of needing to parse each KASAN
> report to test KASAN functionalities.
>
> Stack tests do not work in UML so those tests are protected inside an
> "#if (CONFIG_KASAN_STACK == 1)" so this only runs if stack
> instrumentation is enabled.
>
> Signed-off-by: Patricia Alfonso <trishalfonso@xxxxxxxxxx>
> ---
> The KUnit version of these tests could be in addition to the existing
> tests if that is preferred.
>
> lib/Kconfig.kasan | 2 +-
> lib/test_kasan.c | 352 +++++++++++++++++++++-------------------------
> 2 files changed, 161 insertions(+), 193 deletions(-)
>
> diff --git a/lib/Kconfig.kasan b/lib/Kconfig.kasan
> index 5b54f3c9a741..f8cc9ed60677 100644
> --- a/lib/Kconfig.kasan
> +++ b/lib/Kconfig.kasan
> @@ -160,7 +160,7 @@ config KASAN_VMALLOC
>
> config TEST_KASAN
> tristate "Module for testing KASAN for bug detection"
> - depends on m && KASAN
> + depends on KASAN && KUNIT
> help
> This is a test module doing various nasty things like
> out of bounds accesses, use after free. It is useful for testing
> diff --git a/lib/test_kasan.c b/lib/test_kasan.c
> index 3872d250ed2c..988650387a2a 100644
> --- a/lib/test_kasan.c
> +++ b/lib/test_kasan.c
> @@ -23,17 +23,18 @@
>
> #include <asm/page.h>
>
> +#include <kunit/test.h>
> +
> /*
> * Note: test functions are marked noinline so that their names appear in
> * reports.
> */
>
> -static noinline void __init kmalloc_oob_right(void)
> +static noinline void kmalloc_oob_right(void)
> {
> char *ptr;
> size_t size = 123;
>
> - pr_info("out-of-bounds to right\n");
> ptr = kmalloc(size, GFP_KERNEL);
> if (!ptr) {
> pr_err("Allocation failed\n");
> @@ -44,12 +45,11 @@ static noinline void __init kmalloc_oob_right(void)
> kfree(ptr);
> }
>
> -static noinline void __init kmalloc_oob_left(void)
> +static noinline void kmalloc_oob_left(void)
> {
> char *ptr;
> size_t size = 15;
>
> - pr_info("out-of-bounds to left\n");
> ptr = kmalloc(size, GFP_KERNEL);
> if (!ptr) {
> pr_err("Allocation failed\n");
> @@ -60,12 +60,11 @@ static noinline void __init kmalloc_oob_left(void)
> kfree(ptr);
> }
>
> -static noinline void __init kmalloc_node_oob_right(void)
> +static noinline void kmalloc_node_oob_right(void)
> {
> char *ptr;
> size_t size = 4096;
>
> - pr_info("kmalloc_node(): out-of-bounds to right\n");
> ptr = kmalloc_node(size, GFP_KERNEL, 0);
> if (!ptr) {
> pr_err("Allocation failed\n");
> @@ -77,7 +76,7 @@ static noinline void __init kmalloc_node_oob_right(void)
> }
>
> #ifdef CONFIG_SLUB
> -static noinline void __init kmalloc_pagealloc_oob_right(void)
> +static noinline void kmalloc_pagealloc_oob_right(void)
> {
> char *ptr;
> size_t size = KMALLOC_MAX_CACHE_SIZE + 10;
> @@ -85,7 +84,6 @@ static noinline void __init kmalloc_pagealloc_oob_right(void)
> /* Allocate a chunk that does not fit into a SLUB cache to trigger
> * the page allocator fallback.
> */
> - pr_info("kmalloc pagealloc allocation: out-of-bounds to right\n");
> ptr = kmalloc(size, GFP_KERNEL);
> if (!ptr) {
> pr_err("Allocation failed\n");
> @@ -96,12 +94,11 @@ static noinline void __init kmalloc_pagealloc_oob_right(void)
> kfree(ptr);
> }
>
> -static noinline void __init kmalloc_pagealloc_uaf(void)
> +static noinline void kmalloc_pagealloc_uaf(void)
> {
> char *ptr;
> size_t size = KMALLOC_MAX_CACHE_SIZE + 10;
>
> - pr_info("kmalloc pagealloc allocation: use-after-free\n");
> ptr = kmalloc(size, GFP_KERNEL);
> if (!ptr) {
> pr_err("Allocation failed\n");
> @@ -112,12 +109,11 @@ static noinline void __init kmalloc_pagealloc_uaf(void)
> ptr[0] = 0;
> }
>
> -static noinline void __init kmalloc_pagealloc_invalid_free(void)
> +static noinline void kmalloc_pagealloc_invalid_free(void)
> {
> char *ptr;
> size_t size = KMALLOC_MAX_CACHE_SIZE + 10;
>
> - pr_info("kmalloc pagealloc allocation: invalid-free\n");
> ptr = kmalloc(size, GFP_KERNEL);
> if (!ptr) {
> pr_err("Allocation failed\n");
> @@ -128,14 +124,13 @@ static noinline void __init kmalloc_pagealloc_invalid_free(void)
> }
> #endif
>
> -static noinline void __init kmalloc_large_oob_right(void)
> +static noinline void kmalloc_large_oob_right(void)
> {
> 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.
> */
> - pr_info("kmalloc large allocation: out-of-bounds to right\n");
> ptr = kmalloc(size, GFP_KERNEL);
> if (!ptr) {
> pr_err("Allocation failed\n");
> @@ -146,13 +141,12 @@ static noinline void __init kmalloc_large_oob_right(void)
> kfree(ptr);
> }
>
> -static noinline void __init kmalloc_oob_krealloc_more(void)
> +static noinline void kmalloc_oob_krealloc_more(void)
> {
> char *ptr1, *ptr2;
> size_t size1 = 17;
> size_t size2 = 19;
>
> - pr_info("out-of-bounds after krealloc more\n");
> ptr1 = kmalloc(size1, GFP_KERNEL);
> ptr2 = krealloc(ptr1, size2, GFP_KERNEL);
> if (!ptr1 || !ptr2) {
> @@ -166,13 +160,12 @@ static noinline void __init kmalloc_oob_krealloc_more(void)
> kfree(ptr2);
> }
>
> -static noinline void __init kmalloc_oob_krealloc_less(void)
> +static noinline void kmalloc_oob_krealloc_less(void)
> {
> char *ptr1, *ptr2;
> size_t size1 = 17;
> size_t size2 = 15;
>
> - pr_info("out-of-bounds after krealloc less\n");
> ptr1 = kmalloc(size1, GFP_KERNEL);
> ptr2 = krealloc(ptr1, size2, GFP_KERNEL);
> if (!ptr1 || !ptr2) {
> @@ -184,13 +177,12 @@ static noinline void __init kmalloc_oob_krealloc_less(void)
> kfree(ptr2);
> }
>
> -static noinline void __init kmalloc_oob_16(void)
> +static noinline void kmalloc_oob_16(void)
> {
> struct {
> u64 words[2];
> } *ptr1, *ptr2;
>
> - pr_info("kmalloc out-of-bounds for 16-bytes access\n");
> ptr1 = kmalloc(sizeof(*ptr1) - 3, GFP_KERNEL);
> ptr2 = kmalloc(sizeof(*ptr2), GFP_KERNEL);
> if (!ptr1 || !ptr2) {
> @@ -204,12 +196,11 @@ static noinline void __init kmalloc_oob_16(void)
> kfree(ptr2);
> }
>
> -static noinline void __init kmalloc_oob_memset_2(void)
> +static noinline void kmalloc_oob_memset_2(void)
> {
> char *ptr;
> size_t size = 8;
>
> - pr_info("out-of-bounds in memset2\n");
> ptr = kmalloc(size, GFP_KERNEL);
> if (!ptr) {
> pr_err("Allocation failed\n");
> @@ -220,12 +211,11 @@ static noinline void __init kmalloc_oob_memset_2(void)
> kfree(ptr);
> }
>
> -static noinline void __init kmalloc_oob_memset_4(void)
> +static noinline void kmalloc_oob_memset_4(void)
> {
> char *ptr;
> size_t size = 8;
>
> - pr_info("out-of-bounds in memset4\n");
> ptr = kmalloc(size, GFP_KERNEL);
> if (!ptr) {
> pr_err("Allocation failed\n");
> @@ -237,12 +227,11 @@ static noinline void __init kmalloc_oob_memset_4(void)
> }
>
>
> -static noinline void __init kmalloc_oob_memset_8(void)
> +static noinline void kmalloc_oob_memset_8(void)
> {
> char *ptr;
> size_t size = 8;
>
> - pr_info("out-of-bounds in memset8\n");
> ptr = kmalloc(size, GFP_KERNEL);
> if (!ptr) {
> pr_err("Allocation failed\n");
> @@ -253,12 +242,11 @@ static noinline void __init kmalloc_oob_memset_8(void)
> kfree(ptr);
> }
>
> -static noinline void __init kmalloc_oob_memset_16(void)
> +static noinline void kmalloc_oob_memset_16(void)
> {
> char *ptr;
> size_t size = 16;
>
> - pr_info("out-of-bounds in memset16\n");
> ptr = kmalloc(size, GFP_KERNEL);
> if (!ptr) {
> pr_err("Allocation failed\n");
> @@ -269,12 +257,11 @@ static noinline void __init kmalloc_oob_memset_16(void)
> kfree(ptr);
> }
>
> -static noinline void __init kmalloc_oob_in_memset(void)
> +static noinline void kmalloc_oob_in_memset(void)
> {
> char *ptr;
> size_t size = 666;
>
> - pr_info("out-of-bounds in memset\n");
> ptr = kmalloc(size, GFP_KERNEL);
> if (!ptr) {
> pr_err("Allocation failed\n");
> @@ -285,12 +272,11 @@ static noinline void __init kmalloc_oob_in_memset(void)
> kfree(ptr);
> }
>
> -static noinline void __init kmalloc_uaf(void)
> +static noinline void kmalloc_uaf(void)
> {
> char *ptr;
> size_t size = 10;
>
> - pr_info("use-after-free\n");
> ptr = kmalloc(size, GFP_KERNEL);
> if (!ptr) {
> pr_err("Allocation failed\n");
> @@ -301,12 +287,11 @@ static noinline void __init kmalloc_uaf(void)
> *(ptr + 8) = 'x';
> }
>
> -static noinline void __init kmalloc_uaf_memset(void)
> +static noinline void kmalloc_uaf_memset(void)
> {
> char *ptr;
> size_t size = 33;
>
> - pr_info("use-after-free in memset\n");
> ptr = kmalloc(size, GFP_KERNEL);
> if (!ptr) {
> pr_err("Allocation failed\n");
> @@ -317,12 +302,11 @@ static noinline void __init kmalloc_uaf_memset(void)
> memset(ptr, 0, size);
> }
>
> -static noinline void __init kmalloc_uaf2(void)
> +static noinline void kmalloc_uaf2(void)
> {
> char *ptr1, *ptr2;
> size_t size = 43;
>
> - pr_info("use-after-free after another kmalloc\n");
> ptr1 = kmalloc(size, GFP_KERNEL);
> if (!ptr1) {
> pr_err("Allocation failed\n");
> @@ -342,14 +326,13 @@ static noinline void __init kmalloc_uaf2(void)
> kfree(ptr2);
> }
>
> -static noinline void __init kfree_via_page(void)
> +static noinline void kfree_via_page(void)
> {
> char *ptr;
> size_t size = 8;
> struct page *page;
> unsigned long offset;
>
> - pr_info("invalid-free false positive (via page)\n");
> ptr = kmalloc(size, GFP_KERNEL);
> if (!ptr) {
> pr_err("Allocation failed\n");
> @@ -361,13 +344,12 @@ static noinline void __init kfree_via_page(void)
> kfree(page_address(page) + offset);
> }
>
> -static noinline void __init kfree_via_phys(void)
> +static noinline void kfree_via_phys(void)
> {
> char *ptr;
> size_t size = 8;
> phys_addr_t phys;
>
> - pr_info("invalid-free false positive (via phys)\n");
> ptr = kmalloc(size, GFP_KERNEL);
> if (!ptr) {
> pr_err("Allocation failed\n");
> @@ -378,7 +360,7 @@ static noinline void __init kfree_via_phys(void)
> kfree(phys_to_virt(phys));
> }
>
> -static noinline void __init kmem_cache_oob(void)
> +static noinline void kmem_cache_oob(void)
> {
> char *p;
> size_t size = 200;
> @@ -389,7 +371,6 @@ static noinline void __init kmem_cache_oob(void)
> pr_err("Cache allocation failed\n");
> return;
> }
> - pr_info("out-of-bounds in kmem_cache_alloc\n");
> p = kmem_cache_alloc(cache, GFP_KERNEL);
> if (!p) {
> pr_err("Allocation failed\n");
> @@ -402,7 +383,7 @@ static noinline void __init kmem_cache_oob(void)
> kmem_cache_destroy(cache);
> }
>
> -static noinline void __init memcg_accounted_kmem_cache(void)
> +static noinline void memcg_accounted_kmem_cache(void)
> {
> int i;
> char *p;
> @@ -415,7 +396,6 @@ static noinline void __init memcg_accounted_kmem_cache(void)
> return;
> }
>
> - pr_info("allocate memcg accounted object\n");
> /*
> * Several allocations with a delay to allow for lazy per memcg kmem
> * cache creation.
> @@ -435,31 +415,19 @@ static noinline void __init memcg_accounted_kmem_cache(void)
>
> static char global_array[10];
>
> -static noinline void __init kasan_global_oob(void)
> +static noinline void kasan_global_oob(void)
> {
> volatile int i = 3;
> char *p = &global_array[ARRAY_SIZE(global_array) + i];
>
> - pr_info("out-of-bounds global variable\n");
> - *(volatile char *)p;
> -}
> -
> -static noinline void __init kasan_stack_oob(void)
Let's keep it but also make dependent on CONFIG_KASAN_STACK
> -{
> - char stack_array[10];
> - volatile int i = 0;
> - char *p = &stack_array[ARRAY_SIZE(stack_array) + i];
> -
> - pr_info("out-of-bounds on stack\n");
> *(volatile char *)p;
> }
>
> -static noinline void __init ksize_unpoisons_memory(void)
> +static noinline void ksize_unpoisons_memory(void)
> {
> char *ptr;
> size_t size = 123, real_size;
>
> - pr_info("ksize() unpoisons the whole allocated chunk\n");
> ptr = kmalloc(size, GFP_KERNEL);
> if (!ptr) {
> pr_err("Allocation failed\n");
> @@ -473,72 +441,36 @@ static noinline void __init ksize_unpoisons_memory(void)
> kfree(ptr);
> }
>
> -static noinline void __init copy_user_test(void)
> +#if (CONFIG_KASAN_STACK == 1)
The more common syntax for this is:
#ifdef CONFIG_KASAN_STACK
but it would even better to do:
if (IS_ENABLED(CONFIG_KASAN_STACK))
and return early. This way we at least test compilation (e.g.
CONFIG_KASAN_STACK is not supported on your arch, you change tests and
build break them because they were not even compiled).
> +static noinline void kasan_stack_oob(void)
> {
> - char *kmem;
> - char __user *usermem;
> - size_t size = 10;
> - int 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;
> - }
> -
> - pr_info("out-of-bounds in copy_from_user()\n");
> - unused = copy_from_user(kmem, usermem, size + 1);
Why is all of this removed?
Most of these tests are hard earned and test some special corner cases.
> -
> - 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);
> + char stack_array[10];
> + volatile int i = 0;
> + char *p = &stack_array[ARRAY_SIZE(stack_array) + i];
>
> - vm_munmap((unsigned long)usermem, PAGE_SIZE);
> - kfree(kmem);
> + *(volatile char *)p;
> }
>
> -static noinline void __init kasan_alloca_oob_left(void)
> +static noinline void kasan_alloca_oob_left(void)
> {
> volatile int i = 10;
> char alloca_array[i];
> char *p = alloca_array - 1;
>
> - pr_info("out-of-bounds to left on alloca\n");
> *(volatile char *)p;
> }
>
> -static noinline void __init kasan_alloca_oob_right(void)
> +static noinline void kasan_alloca_oob_right(void)
> {
> volatile int i = 10;
> char alloca_array[i];
> char *p = alloca_array + i;
>
> - pr_info("out-of-bounds to right on alloca\n");
> *(volatile char *)p;
> }
> +#endif /* CONFIG_KASAN_STACK */
>
> -static noinline void __init kmem_cache_double_free(void)
> +static noinline void kmem_cache_double_free(void)
> {
> char *p;
> size_t size = 200;
> @@ -549,7 +481,6 @@ static noinline void __init kmem_cache_double_free(void)
> pr_err("Cache allocation failed\n");
> return;
> }
> - pr_info("double-free on heap object\n");
> p = kmem_cache_alloc(cache, GFP_KERNEL);
> if (!p) {
> pr_err("Allocation failed\n");
> @@ -562,7 +493,7 @@ static noinline void __init kmem_cache_double_free(void)
> kmem_cache_destroy(cache);
> }
>
> -static noinline void __init kmem_cache_invalid_free(void)
> +static noinline void kmem_cache_invalid_free(void)
> {
> char *p;
> size_t size = 200;
> @@ -574,7 +505,6 @@ static noinline void __init kmem_cache_invalid_free(void)
> pr_err("Cache allocation failed\n");
> return;
> }
> - pr_info("invalid-free of heap object\n");
> p = kmem_cache_alloc(cache, GFP_KERNEL);
> if (!p) {
> pr_err("Allocation failed\n");
> @@ -594,12 +524,11 @@ static noinline void __init kmem_cache_invalid_free(void)
> kmem_cache_destroy(cache);
> }
>
> -static noinline void __init kasan_memchr(void)
> +static noinline void kasan_memchr(void)
> {
> char *ptr;
> size_t size = 24;
>
> - pr_info("out-of-bounds in memchr\n");
> ptr = kmalloc(size, GFP_KERNEL | __GFP_ZERO);
> if (!ptr)
> return;
> @@ -608,13 +537,12 @@ static noinline void __init kasan_memchr(void)
> kfree(ptr);
> }
>
> -static noinline void __init kasan_memcmp(void)
> +static noinline void kasan_memcmp(void)
> {
> char *ptr;
> size_t size = 24;
> int arr[9];
>
> - pr_info("out-of-bounds in memcmp\n");
> ptr = kmalloc(size, GFP_KERNEL | __GFP_ZERO);
> if (!ptr)
> return;
> @@ -624,12 +552,11 @@ static noinline void __init kasan_memcmp(void)
> kfree(ptr);
> }
>
> -static noinline void __init kasan_strings(void)
> +static noinline void kasan_strings(void)
> {
> char *ptr;
> size_t size = 24;
>
> - pr_info("use-after-free in strchr\n");
> ptr = kmalloc(size, GFP_KERNEL | __GFP_ZERO);
> if (!ptr)
> return;
> @@ -645,23 +572,18 @@ static noinline void __init kasan_strings(void)
> ptr += 16;
> strchr(ptr, '1');
>
> - pr_info("use-after-free in strrchr\n");
> strrchr(ptr, '1');
>
> - pr_info("use-after-free in strcmp\n");
> strcmp(ptr, "2");
Such tests now need to be split into multiple tests, one error per
test. Otherwise they don't test what they are supposed to test (each
of these produces an error).
Well, I mean, currently they don't test anything at all, but with
kunit we actually can test this, so it would be good to actually test
what this test was supposed to test :)
This applies to other tests as well.
> - pr_info("use-after-free in strncmp\n");
> strncmp(ptr, "2", 1);
>
> - pr_info("use-after-free in strlen\n");
> strlen(ptr);
>
> - pr_info("use-after-free in strnlen\n");
> strnlen(ptr, 1);
> }
>
> -static noinline void __init kasan_bitops(void)
> +static noinline void kasan_bitops(void)
> {
> /*
> * Allocate 1 more byte, which causes kzalloc to round up to 16-bytes;
> @@ -676,70 +598,52 @@ static noinline void __init kasan_bitops(void)
> * below accesses are still out-of-bounds, since bitops are defined to
> * operate on the whole long the bit is in.
> */
> - pr_info("out-of-bounds in set_bit\n");
> set_bit(BITS_PER_LONG, bits);
>
> - pr_info("out-of-bounds in __set_bit\n");
> __set_bit(BITS_PER_LONG, bits);
>
> - pr_info("out-of-bounds in clear_bit\n");
> clear_bit(BITS_PER_LONG, bits);
>
> - pr_info("out-of-bounds in __clear_bit\n");
> __clear_bit(BITS_PER_LONG, bits);
>
> - pr_info("out-of-bounds in clear_bit_unlock\n");
> clear_bit_unlock(BITS_PER_LONG, bits);
>
> - pr_info("out-of-bounds in __clear_bit_unlock\n");
> __clear_bit_unlock(BITS_PER_LONG, bits);
>
> - pr_info("out-of-bounds in change_bit\n");
> change_bit(BITS_PER_LONG, bits);
>
> - pr_info("out-of-bounds in __change_bit\n");
> __change_bit(BITS_PER_LONG, bits);
>
> /*
> * Below calls try to access bit beyond allocated memory.
> */
> - pr_info("out-of-bounds in test_and_set_bit\n");
> test_and_set_bit(BITS_PER_LONG + BITS_PER_BYTE, bits);
>
> - pr_info("out-of-bounds in __test_and_set_bit\n");
> __test_and_set_bit(BITS_PER_LONG + BITS_PER_BYTE, bits);
>
> - pr_info("out-of-bounds in test_and_set_bit_lock\n");
> test_and_set_bit_lock(BITS_PER_LONG + BITS_PER_BYTE, bits);
>
> - pr_info("out-of-bounds in test_and_clear_bit\n");
> test_and_clear_bit(BITS_PER_LONG + BITS_PER_BYTE, bits);
>
> - pr_info("out-of-bounds in __test_and_clear_bit\n");
> __test_and_clear_bit(BITS_PER_LONG + BITS_PER_BYTE, bits);
>
> - pr_info("out-of-bounds in test_and_change_bit\n");
> test_and_change_bit(BITS_PER_LONG + BITS_PER_BYTE, bits);
>
> - pr_info("out-of-bounds in __test_and_change_bit\n");
> __test_and_change_bit(BITS_PER_LONG + BITS_PER_BYTE, bits);
>
> - pr_info("out-of-bounds in test_bit\n");
> (void)test_bit(BITS_PER_LONG + BITS_PER_BYTE, bits);
>
> #if defined(clear_bit_unlock_is_negative_byte)
> - pr_info("out-of-bounds in clear_bit_unlock_is_negative_byte\n");
> clear_bit_unlock_is_negative_byte(BITS_PER_LONG + BITS_PER_BYTE, bits);
> #endif
> kfree(bits);
> }
>
> -static noinline void __init kmalloc_double_kzfree(void)
> +static noinline void kmalloc_double_kzfree(void)
Since it seems we will need v2, it will help if you move these
mechanical diffs to a separate patch. I mean removal of __init and
pr_info. These produce lots of changes and it's hard to separate out
more meaningful changes from this mechanical noise.
> {
> char *ptr;
> size_t size = 16;
>
> - pr_info("double-free (kzfree)\n");
> ptr = kmalloc(size, GFP_KERNEL);
> if (!ptr) {
> pr_err("Allocation failed\n");
> @@ -750,29 +654,130 @@ static noinline void __init kmalloc_double_kzfree(void)
> kzfree(ptr);
> }
>
> -#ifdef CONFIG_KASAN_VMALLOC
> -static noinline void __init vmalloc_oob(void)
> +static void kunit_test_oob(struct kunit *test)
> +{
> + KUNIT_EXPECT_KASAN_FAIL(test, kmalloc_oob_right());
I think the 2 patches need to be reordered. This
KUNIT_EXPECT_KASAN_FAIL is introduced only in the next patch. This
will break build during bisections.
> + KUNIT_EXPECT_KASAN_FAIL(test, kmalloc_oob_left());
I am wondering if it makes sense to have the "KASAN_FAIL" part be part
of the test itself. It will make the test and assertion local to each
other. I hope later we will add some negative tests as well (without
kasan errors), then people will start copy-pasting these macros and
it's possible I copy-paste macro that checks that the test does not
produce kasan error for my test, which I actually want the macro that
checks for report. Then if my test does not fail, it will be
unnoticed. I may be good to have assertion local to the test itself.
Thoughts?
> + KUNIT_EXPECT_KASAN_FAIL(test, kmalloc_node_oob_right());
> + KUNIT_EXPECT_KASAN_FAIL(test, kmalloc_large_oob_right());
> + KUNIT_EXPECT_KASAN_FAIL(test, kmalloc_oob_krealloc_more());
> + KUNIT_EXPECT_KASAN_FAIL(test, kmalloc_oob_krealloc_less());
> + KUNIT_EXPECT_KASAN_FAIL(test, kmalloc_oob_16());
> + KUNIT_EXPECT_KASAN_FAIL(test, kmalloc_oob_in_memset());
> + KUNIT_EXPECT_KASAN_FAIL(test, kmalloc_oob_memset_2());
> + KUNIT_EXPECT_KASAN_FAIL(test, kmalloc_oob_memset_4());
> + KUNIT_EXPECT_KASAN_FAIL(test, kmalloc_oob_memset_8());
> + KUNIT_EXPECT_KASAN_FAIL(test, kmalloc_oob_memset_16());
> + KUNIT_EXPECT_KASAN_FAIL(test, kmem_cache_oob());
> + KUNIT_EXPECT_KASAN_FAIL(test, kasan_global_oob());
> + KUNIT_EXPECT_KASAN_FAIL(test, ksize_unpoisons_memory());
> + KUNIT_EXPECT_KASAN_FAIL(test, kasan_memchr());
> + KUNIT_EXPECT_KASAN_FAIL(test, kasan_memcmp());
> + KUNIT_EXPECT_KASAN_FAIL(test, kasan_strings());
> + KUNIT_EXPECT_KASAN_FAIL(test, kasan_bitops());
> +#ifdef CONFIG_SLUB
> + KUNIT_EXPECT_KASAN_FAIL(test, kmalloc_pagealloc_oob_right());
> +#endif /* CONFIG_SLUB */
> +
> +#if (CONFIG_KASAN_STACK == 1)
> + KUNIT_EXPECT_KASAN_FAIL(test, kasan_stack_oob());
> + KUNIT_EXPECT_KASAN_FAIL(test, kasan_alloca_oob_right());
> + KUNIT_EXPECT_KASAN_FAIL(test, kasan_alloca_oob_left());
> +#endif /*CONFIG_KASAN_STACK*/
> +}
> +
> +static void kunit_test_uaf(struct kunit *test)
> +{
> +#ifdef CONFIG_SLUB
> + KUNIT_EXPECT_KASAN_FAIL(test, kmalloc_pagealloc_uaf());
> +#endif
> + KUNIT_EXPECT_KASAN_FAIL(test, kmalloc_uaf());
> + KUNIT_EXPECT_KASAN_FAIL(test, kmalloc_uaf_memset());
> + KUNIT_EXPECT_KASAN_FAIL(test, kmalloc_uaf2());
> +}
> +
> +static void kunit_test_invalid_free(struct kunit *test)
> {
> - void *area;
> +#ifdef CONFIG_SLUB
> + KUNIT_EXPECT_KASAN_FAIL(test, kmalloc_pagealloc_invalid_free());
> +#endif
> + KUNIT_EXPECT_KASAN_FAIL(test, kmem_cache_invalid_free());
> + KUNIT_EXPECT_KASAN_FAIL(test, kmem_cache_double_free());
> + KUNIT_EXPECT_KASAN_FAIL(test, kmalloc_double_kzfree());
> +}
>
> - pr_info("vmalloc out-of-bounds\n");
> +static void kunit_test_false_positives(struct kunit *test)
> +{
> + kfree_via_page();
> + kfree_via_phys();
> +}
>
> - /*
> - * We have to be careful not to hit the guard page.
> - * The MMU will catch that and crash us.
> - */
> - area = vmalloc(3000);
> - if (!area) {
> - pr_err("Allocation failed\n");
> +static void kunit_test_memcg(struct kunit *test)
> +{
> + memcg_accounted_kmem_cache();
> +}
> +
> +static struct kunit_case kasan_kunit_test_cases[] = {
> + KUNIT_CASE(kunit_test_oob),
> + KUNIT_CASE(kunit_test_uaf),
> + KUNIT_CASE(kunit_test_invalid_free),
> + KUNIT_CASE(kunit_test_false_positives),
> + KUNIT_CASE(kunit_test_memcg),
> + {}
> +};
> +
> +static struct kunit_suite kasan_kunit_test_suite = {
> + .name = "kasan_kunit_test",
> + .test_cases = kasan_kunit_test_cases,
> +};
> +
> +kunit_test_suite(kasan_kunit_test_suite);
> +
> +#if IS_MODULE(CONFIG_TEST_KASAN)
> +static noinline void __init copy_user_test(void)
> +{
> + char *kmem;
> + char __user *usermem;
> + size_t size = 10;
> + int 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;
> }
>
> - ((volatile char *)area)[3100];
> - vfree(area);
> + 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);
> }
> -#else
> -static void __init vmalloc_oob(void) {}
> -#endif
>
> static int __init kmalloc_tests_init(void)
> {
> @@ -782,44 +787,7 @@ static int __init kmalloc_tests_init(void)
> */
> bool multishot = kasan_save_enable_multi_shot();
>
> - kmalloc_oob_right();
> - kmalloc_oob_left();
> - kmalloc_node_oob_right();
> -#ifdef CONFIG_SLUB
> - kmalloc_pagealloc_oob_right();
> - kmalloc_pagealloc_uaf();
> - kmalloc_pagealloc_invalid_free();
> -#endif
> - kmalloc_large_oob_right();
> - kmalloc_oob_krealloc_more();
> - kmalloc_oob_krealloc_less();
> - kmalloc_oob_16();
> - kmalloc_oob_in_memset();
> - kmalloc_oob_memset_2();
> - kmalloc_oob_memset_4();
> - kmalloc_oob_memset_8();
> - kmalloc_oob_memset_16();
> - kmalloc_uaf();
> - kmalloc_uaf_memset();
> - kmalloc_uaf2();
> - kfree_via_page();
> - kfree_via_phys();
> - kmem_cache_oob();
> - memcg_accounted_kmem_cache();
> - kasan_stack_oob();
> - kasan_global_oob();
> - kasan_alloca_oob_left();
> - kasan_alloca_oob_right();
> - ksize_unpoisons_memory();
> copy_user_test();
> - kmem_cache_double_free();
> - kmem_cache_invalid_free();
> - kasan_memchr();
> - kasan_memcmp();
> - kasan_strings();
> - kasan_bitops();
> - kmalloc_double_kzfree();
> - vmalloc_oob();
>
> kasan_restore_multi_shot(multishot);
>
> @@ -827,4 +795,4 @@ static int __init kmalloc_tests_init(void)
> }
>
> module_init(kmalloc_tests_init);
> -MODULE_LICENSE("GPL");
> +#endif /* IS_MODULE(CONFIG_TEST_KASAN) */
> --
> 2.25.0.265.gbab2e86ba0-goog
>