LXR linux/lib/slub

   1// SPDX-License-Identifier: GPL-2.0
   2#include <kunit/test.h>
   3#include <linux/mm.h>
   4#include <linux/slab.h>
   5#include <linux/module.h>
   6#include <linux/kernel.h>
   7#include "../mm/slab.h"
   8
   9static struct kunit_resource resource;
  10static int slab_errors;
  11
  12static void test_clobber_zone(struct kunit *test)
  13{
  14        struct kmem_cache *s = kmem_cache_create("TestSlub_RZ_alloc", 64, 0,
  15                                SLAB_RED_ZONE, NULL);
  16        u8 *p = kmem_cache_alloc(s, GFP_KERNEL);
  17
  18        kasan_disable_current();
  19        p[64] = 0x12;
  20
  21        validate_slab_cache(s);
  22        KUNIT_EXPECT_EQ(test, 2, slab_errors);
  23
  24        kasan_enable_current();
  25        kmem_cache_free(s, p);
  26        kmem_cache_destroy(s);
  27}
  28
  29#ifndef CONFIG_KASAN
  30static void test_next_pointer(struct kunit *test)
  31{
  32        struct kmem_cache *s = kmem_cache_create("TestSlub_next_ptr_free", 64, 0,
  33                                SLAB_POISON, NULL);
  34        u8 *p = kmem_cache_alloc(s, GFP_KERNEL);
  35        unsigned long tmp;
  36        unsigned long *ptr_addr;
  37
  38        kmem_cache_free(s, p);
  39
  40        ptr_addr = (unsigned long *)(p + s->offset);
  41        tmp = *ptr_addr;
  42        p[s->offset] = 0x12;
  43
  44        /*
  45         * Expecting three errors.
  46         * One for the corrupted freechain and the other one for the wrong
  47         * count of objects in use. The third error is fixing broken cache.
  48         */
  49        validate_slab_cache(s);
  50        KUNIT_EXPECT_EQ(test, 3, slab_errors);
  51
  52        /*
  53         * Try to repair corrupted freepointer.
  54         * Still expecting two errors. The first for the wrong count
  55         * of objects in use.
  56         * The second error is for fixing broken cache.
  57         */
  58        *ptr_addr = tmp;
  59        slab_errors = 0;
  60
  61        validate_slab_cache(s);
  62        KUNIT_EXPECT_EQ(test, 2, slab_errors);
  63
  64        /*
  65         * Previous validation repaired the count of objects in use.
  66         * Now expecting no error.
  67         */
  68        slab_errors = 0;
  69        validate_slab_cache(s);
  70        KUNIT_EXPECT_EQ(test, 0, slab_errors);
  71
  72        kmem_cache_destroy(s);
  73}
  74
  75static void test_first_word(struct kunit *test)
  76{
  77        struct kmem_cache *s = kmem_cache_create("TestSlub_1th_word_free", 64, 0,
  78                                SLAB_POISON, NULL);
  79        u8 *p = kmem_cache_alloc(s, GFP_KERNEL);
  80
  81        kmem_cache_free(s, p);
  82        *p = 0x78;
  83
  84        validate_slab_cache(s);
  85        KUNIT_EXPECT_EQ(test, 2, slab_errors);
  86
  87        kmem_cache_destroy(s);
  88}
  89
  90static void test_clobber_50th_byte(struct kunit *test)
  91{
  92        struct kmem_cache *s = kmem_cache_create("TestSlub_50th_word_free", 64, 0,
  93                                SLAB_POISON, NULL);
  94        u8 *p = kmem_cache_alloc(s, GFP_KERNEL);
  95
  96        kmem_cache_free(s, p);
  97        p[50] = 0x9a;
  98
  99        validate_slab_cache(s);
 100        KUNIT_EXPECT_EQ(test, 2, slab_errors);
 101
 102        kmem_cache_destroy(s);
 103}
 104#endif
 105
 106static void test_clobber_redzone_free(struct kunit *test)
 107{
 108        struct kmem_cache *s = kmem_cache_create("TestSlub_RZ_free", 64, 0,
 109                                SLAB_RED_ZONE, NULL);
 110        u8 *p = kmem_cache_alloc(s, GFP_KERNEL);
 111
 112        kasan_disable_current();
 113        kmem_cache_free(s, p);
 114        p[64] = 0xab;
 115
 116        validate_slab_cache(s);
 117        KUNIT_EXPECT_EQ(test, 2, slab_errors);
 118
 119        kasan_enable_current();
 120        kmem_cache_destroy(s);
 121}
 122
 123static int test_init(struct kunit *test)
 124{
 125        slab_errors = 0;
 126
 127        kunit_add_named_resource(test, NULL, NULL, &resource,
 128                                        "slab_errors", &slab_errors);
 129        return 0;
 130}
 131
 132static struct kunit_case test_cases[] = {
 133        KUNIT_CASE(test_clobber_zone),
 134
 135#ifndef CONFIG_KASAN
 136        KUNIT_CASE(test_next_pointer),
 137        KUNIT_CASE(test_first_word),
 138        KUNIT_CASE(test_clobber_50th_byte),
 139#endif
 140
 141        KUNIT_CASE(test_clobber_redzone_free),
 142        {}
 143};
 144
 145static struct kunit_suite test_suite = {
 146        .name = "slub_test",
 147        .init = test_init,
 148        .test_cases = test_cases,
 149};
 150kunit_test_suite(test_suite);
 151
 152MODULE_LICENSE("GPL");
 153