1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * samples/kmemleak/kmemleak-test.c
4 *
5 * Copyright (C) 2008 ARM Limited
6 * Written by Catalin Marinas <catalin.marinas@arm.com>
7 */
8
9 #define pr_fmt(fmt) "kmemleak: " fmt
10
11 #include <linux/init.h>
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/slab.h>
15 #include <linux/vmalloc.h>
16 #include <linux/list.h>
17 #include <linux/percpu.h>
18 #include <linux/fdtable.h>
19
20 #include <linux/kmemleak.h>
21
22 struct test_node {
23 long header[25];
24 struct list_head list;
25 long footer[25];
26 };
27
28 static LIST_HEAD(test_list);
29 static DEFINE_PER_CPU(void *, kmemleak_test_pointer);
30
31 /*
32 * Some very simple testing. This function needs to be extended for
33 * proper testing.
34 */
kmemleak_test_init(void)35 static int kmemleak_test_init(void)
36 {
37 struct test_node *elem;
38 int i;
39
40 pr_info("Kmemleak testing\n");
41
42 /* make some orphan objects */
43 pr_info("kmalloc(32) = %p\n", kmalloc(32, GFP_KERNEL));
44 pr_info("kmalloc(32) = %p\n", kmalloc(32, GFP_KERNEL));
45 pr_info("kmalloc(1024) = %p\n", kmalloc(1024, GFP_KERNEL));
46 pr_info("kmalloc(1024) = %p\n", kmalloc(1024, GFP_KERNEL));
47 pr_info("kmalloc(2048) = %p\n", kmalloc(2048, GFP_KERNEL));
48 pr_info("kmalloc(2048) = %p\n", kmalloc(2048, GFP_KERNEL));
49 pr_info("kmalloc(4096) = %p\n", kmalloc(4096, GFP_KERNEL));
50 pr_info("kmalloc(4096) = %p\n", kmalloc(4096, GFP_KERNEL));
51 #ifndef CONFIG_MODULES
52 pr_info("kmem_cache_alloc(files_cachep) = %p\n",
53 kmem_cache_alloc(files_cachep, GFP_KERNEL));
54 pr_info("kmem_cache_alloc(files_cachep) = %p\n",
55 kmem_cache_alloc(files_cachep, GFP_KERNEL));
56 #endif
57 pr_info("vmalloc(64) = %p\n", vmalloc(64));
58 pr_info("vmalloc(64) = %p\n", vmalloc(64));
59 pr_info("vmalloc(64) = %p\n", vmalloc(64));
60 pr_info("vmalloc(64) = %p\n", vmalloc(64));
61 pr_info("vmalloc(64) = %p\n", vmalloc(64));
62
63 /*
64 * Add elements to a list. They should only appear as orphan
65 * after the module is removed.
66 */
67 for (i = 0; i < 10; i++) {
68 elem = kzalloc(sizeof(*elem), GFP_KERNEL);
69 pr_info("kzalloc(sizeof(*elem)) = %p\n", elem);
70 if (!elem)
71 return -ENOMEM;
72 INIT_LIST_HEAD(&elem->list);
73 list_add_tail(&elem->list, &test_list);
74 }
75
76 for_each_possible_cpu(i) {
77 per_cpu(kmemleak_test_pointer, i) = kmalloc(129, GFP_KERNEL);
78 pr_info("kmalloc(129) = %p\n",
79 per_cpu(kmemleak_test_pointer, i));
80 }
81
82 pr_info("__alloc_percpu(64, 4) = %p\n", __alloc_percpu(64, 4));
83
84 return 0;
85 }
86 module_init(kmemleak_test_init);
87
kmemleak_test_exit(void)88 static void __exit kmemleak_test_exit(void)
89 {
90 struct test_node *elem, *tmp;
91
92 /*
93 * Remove the list elements without actually freeing the
94 * memory.
95 */
96 list_for_each_entry_safe(elem, tmp, &test_list, list)
97 list_del(&elem->list);
98 }
99 module_exit(kmemleak_test_exit);
100
101 MODULE_DESCRIPTION("Sample module to leak memory for kmemleak testing");
102 MODULE_LICENSE("GPL");
103