linux/lib/slub_kunit.c
Hyeonggon Yoo a285909f47 mm/slub, kunit: Make slub_kunit unaffected by user specified flags
slub_kunit does not expect other debugging flags to be set when running
tests. When SLAB_RED_ZONE flag is set globally, test fails because the
flag affects number of errors reported.

To make slub_kunit unaffected by user specified debugging flags,
introduce SLAB_NO_USER_FLAGS to ignore them. With this flag, only flags
specified in the code are used and others are ignored.

Suggested-by: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Link: https://lore.kernel.org/r/Yk0sY9yoJhFEXWOg@hyeyoo
2022-04-06 10:11:48 +02:00

153 lines
3.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <kunit/test.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include "../mm/slab.h"
static struct kunit_resource resource;
static int slab_errors;
static void test_clobber_zone(struct kunit *test)
{
struct kmem_cache *s = kmem_cache_create("TestSlub_RZ_alloc", 64, 0,
SLAB_RED_ZONE|SLAB_NO_USER_FLAGS, NULL);
u8 *p = kmem_cache_alloc(s, GFP_KERNEL);
kasan_disable_current();
p[64] = 0x12;
validate_slab_cache(s);
KUNIT_EXPECT_EQ(test, 2, slab_errors);
kasan_enable_current();
kmem_cache_free(s, p);
kmem_cache_destroy(s);
}
#ifndef CONFIG_KASAN
static void test_next_pointer(struct kunit *test)
{
struct kmem_cache *s = kmem_cache_create("TestSlub_next_ptr_free", 64, 0,
SLAB_POISON|SLAB_NO_USER_FLAGS, NULL);
u8 *p = kmem_cache_alloc(s, GFP_KERNEL);
unsigned long tmp;
unsigned long *ptr_addr;
kmem_cache_free(s, p);
ptr_addr = (unsigned long *)(p + s->offset);
tmp = *ptr_addr;
p[s->offset] = 0x12;
/*
* Expecting three errors.
* One for the corrupted freechain and the other one for the wrong
* count of objects in use. The third error is fixing broken cache.
*/
validate_slab_cache(s);
KUNIT_EXPECT_EQ(test, 3, slab_errors);
/*
* Try to repair corrupted freepointer.
* Still expecting two errors. The first for the wrong count
* of objects in use.
* The second error is for fixing broken cache.
*/
*ptr_addr = tmp;
slab_errors = 0;
validate_slab_cache(s);
KUNIT_EXPECT_EQ(test, 2, slab_errors);
/*
* Previous validation repaired the count of objects in use.
* Now expecting no error.
*/
slab_errors = 0;
validate_slab_cache(s);
KUNIT_EXPECT_EQ(test, 0, slab_errors);
kmem_cache_destroy(s);
}
static void test_first_word(struct kunit *test)
{
struct kmem_cache *s = kmem_cache_create("TestSlub_1th_word_free", 64, 0,
SLAB_POISON|SLAB_NO_USER_FLAGS, NULL);
u8 *p = kmem_cache_alloc(s, GFP_KERNEL);
kmem_cache_free(s, p);
*p = 0x78;
validate_slab_cache(s);
KUNIT_EXPECT_EQ(test, 2, slab_errors);
kmem_cache_destroy(s);
}
static void test_clobber_50th_byte(struct kunit *test)
{
struct kmem_cache *s = kmem_cache_create("TestSlub_50th_word_free", 64, 0,
SLAB_POISON|SLAB_NO_USER_FLAGS, NULL);
u8 *p = kmem_cache_alloc(s, GFP_KERNEL);
kmem_cache_free(s, p);
p[50] = 0x9a;
validate_slab_cache(s);
KUNIT_EXPECT_EQ(test, 2, slab_errors);
kmem_cache_destroy(s);
}
#endif
static void test_clobber_redzone_free(struct kunit *test)
{
struct kmem_cache *s = kmem_cache_create("TestSlub_RZ_free", 64, 0,
SLAB_RED_ZONE|SLAB_NO_USER_FLAGS, NULL);
u8 *p = kmem_cache_alloc(s, GFP_KERNEL);
kasan_disable_current();
kmem_cache_free(s, p);
p[64] = 0xab;
validate_slab_cache(s);
KUNIT_EXPECT_EQ(test, 2, slab_errors);
kasan_enable_current();
kmem_cache_destroy(s);
}
static int test_init(struct kunit *test)
{
slab_errors = 0;
kunit_add_named_resource(test, NULL, NULL, &resource,
"slab_errors", &slab_errors);
return 0;
}
static struct kunit_case test_cases[] = {
KUNIT_CASE(test_clobber_zone),
#ifndef CONFIG_KASAN
KUNIT_CASE(test_next_pointer),
KUNIT_CASE(test_first_word),
KUNIT_CASE(test_clobber_50th_byte),
#endif
KUNIT_CASE(test_clobber_redzone_free),
{}
};
static struct kunit_suite test_suite = {
.name = "slub_test",
.init = test_init,
.test_cases = test_cases,
};
kunit_test_suite(test_suite);
MODULE_LICENSE("GPL");