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 	return 0;
83 }
84 module_init(kmemleak_test_init);
85 
kmemleak_test_exit(void)86 static void __exit kmemleak_test_exit(void)
87 {
88 	struct test_node *elem, *tmp;
89 
90 	/*
91 	 * Remove the list elements without actually freeing the
92 	 * memory.
93 	 */
94 	list_for_each_entry_safe(elem, tmp, &test_list, list)
95 		list_del(&elem->list);
96 }
97 module_exit(kmemleak_test_exit);
98 
99 MODULE_LICENSE("GPL");
100