2022-02-16 04:40:15

by andrey.konovalov

Subject: [PATCH mm] fix for "kasan: improve vmalloc tests"

From: Andrey Konovalov <[email protected]>

vmap_tags() and vm_map_ram_tags() pass invalid page array size to
vm_map_ram() and vm_unmap_ram(). It's supposed to be 1, but it's
1 << order == 2 currently.

Remove order variable (it can only be 0 with the current code)
and hardcode the number of pages in these tests.

Signed-off-by: Andrey Konovalov <[email protected]>
---
lib/test_kasan.c | 16 +++++++---------
1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/lib/test_kasan.c b/lib/test_kasan.c
index 491a82006f06..8416161d5177 100644
--- a/lib/test_kasan.c
+++ b/lib/test_kasan.c
@@ -1149,7 +1149,6 @@ static void vmap_tags(struct kunit *test)
{
char *p_ptr, *v_ptr;
struct page *p_page, *v_page;
- size_t order = 1;

/*
* This test is specifically crafted for the software tag-based mode,
@@ -1159,12 +1158,12 @@ static void vmap_tags(struct kunit *test)

KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_VMALLOC);

- p_page = alloc_pages(GFP_KERNEL, order);
+ 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 << order, VM_MAP, PAGE_KERNEL);
+ v_ptr = vmap(&p_page, 1, VM_MAP, PAGE_KERNEL);
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, v_ptr);

/*
@@ -1186,14 +1185,13 @@ static void vmap_tags(struct kunit *test)
KUNIT_EXPECT_PTR_EQ(test, p_page, v_page);

vunmap(v_ptr);
- free_pages((unsigned long)p_ptr, order);
+ free_pages((unsigned long)p_ptr, 1);
}

static void vm_map_ram_tags(struct kunit *test)
{
char *p_ptr, *v_ptr;
struct page *page;
- size_t order = 1;

/*
* This test is specifically crafted for the software tag-based mode,
@@ -1201,12 +1199,12 @@ static void vm_map_ram_tags(struct kunit *test)
*/
KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_SW_TAGS);

- page = alloc_pages(GFP_KERNEL, order);
+ 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 << order, -1);
+ 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);
@@ -1216,8 +1214,8 @@ static void vm_map_ram_tags(struct kunit *test)
*p_ptr = 0;
*v_ptr = 0;

- vm_unmap_ram(v_ptr, 1 << order);
- free_pages((unsigned long)p_ptr, order);
+ vm_unmap_ram(v_ptr, 1);
+ free_pages((unsigned long)p_ptr, 1);
}

static void vmalloc_percpu(struct kunit *test)
--
2.25.1

2022-02-16 10:03:31

by Marco Elver

Subject: Re: [PATCH mm] fix for "kasan: improve vmalloc tests"

On Tue, 15 Feb 2022 at 19:39, <[email protected]> wrote:
>
> From: Andrey Konovalov <[email protected]>
>
> vmap_tags() and vm_map_ram_tags() pass invalid page array size to
> vm_map_ram() and vm_unmap_ram(). It's supposed to be 1, but it's
> 1 << order == 2 currently.
>
> Remove order variable (it can only be 0 with the current code)
> and hardcode the number of pages in these tests.
>
> Signed-off-by: Andrey Konovalov <[email protected]>

Acked-by: Marco Elver <[email protected]>


> ---
> lib/test_kasan.c | 16 +++++++---------
> 1 file changed, 7 insertions(+), 9 deletions(-)
>
> diff --git a/lib/test_kasan.c b/lib/test_kasan.c
> index 491a82006f06..8416161d5177 100644
> --- a/lib/test_kasan.c
> +++ b/lib/test_kasan.c
> @@ -1149,7 +1149,6 @@ static void vmap_tags(struct kunit *test)
> {
> char *p_ptr, *v_ptr;
> struct page *p_page, *v_page;
> - size_t order = 1;
>
> /*
> * This test is specifically crafted for the software tag-based mode,
> @@ -1159,12 +1158,12 @@ static void vmap_tags(struct kunit *test)
>
> KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_VMALLOC);
>
> - p_page = alloc_pages(GFP_KERNEL, order);
> + 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 << order, VM_MAP, PAGE_KERNEL);
> + v_ptr = vmap(&p_page, 1, VM_MAP, PAGE_KERNEL);
> KUNIT_ASSERT_NOT_ERR_OR_NULL(test, v_ptr);
>
> /*
> @@ -1186,14 +1185,13 @@ static void vmap_tags(struct kunit *test)
> KUNIT_EXPECT_PTR_EQ(test, p_page, v_page);
>
> vunmap(v_ptr);
> - free_pages((unsigned long)p_ptr, order);
> + free_pages((unsigned long)p_ptr, 1);
> }
>
> static void vm_map_ram_tags(struct kunit *test)
> {
> char *p_ptr, *v_ptr;
> struct page *page;
> - size_t order = 1;
>
> /*
> * This test is specifically crafted for the software tag-based mode,
> @@ -1201,12 +1199,12 @@ static void vm_map_ram_tags(struct kunit *test)
> */
> KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_SW_TAGS);
>
> - page = alloc_pages(GFP_KERNEL, order);
> + 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 << order, -1);
> + 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);
> @@ -1216,8 +1214,8 @@ static void vm_map_ram_tags(struct kunit *test)
> *p_ptr = 0;
> *v_ptr = 0;
>
> - vm_unmap_ram(v_ptr, 1 << order);
> - free_pages((unsigned long)p_ptr, order);
> + vm_unmap_ram(v_ptr, 1);
> + free_pages((unsigned long)p_ptr, 1);
> }
>
> static void vmalloc_percpu(struct kunit *test)
> --
> 2.25.1
>