1*a2818ee4SJoe Lawrence // SPDX-License-Identifier: GPL-2.0
2*a2818ee4SJoe Lawrence // Copyright (C) 2018 Joe Lawrence <joe.lawrence@redhat.com>
3*a2818ee4SJoe Lawrence
4*a2818ee4SJoe Lawrence #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
5*a2818ee4SJoe Lawrence
6*a2818ee4SJoe Lawrence #include <linux/module.h>
7*a2818ee4SJoe Lawrence #include <linux/kernel.h>
8*a2818ee4SJoe Lawrence #include <linux/livepatch.h>
9*a2818ee4SJoe Lawrence
10*a2818ee4SJoe Lawrence static int pre_patch_ret;
11*a2818ee4SJoe Lawrence module_param(pre_patch_ret, int, 0644);
12*a2818ee4SJoe Lawrence MODULE_PARM_DESC(pre_patch_ret, "pre_patch_ret (default=0)");
13*a2818ee4SJoe Lawrence
14*a2818ee4SJoe Lawrence static const char *const module_state[] = {
15*a2818ee4SJoe Lawrence [MODULE_STATE_LIVE] = "[MODULE_STATE_LIVE] Normal state",
16*a2818ee4SJoe Lawrence [MODULE_STATE_COMING] = "[MODULE_STATE_COMING] Full formed, running module_init",
17*a2818ee4SJoe Lawrence [MODULE_STATE_GOING] = "[MODULE_STATE_GOING] Going away",
18*a2818ee4SJoe Lawrence [MODULE_STATE_UNFORMED] = "[MODULE_STATE_UNFORMED] Still setting it up",
19*a2818ee4SJoe Lawrence };
20*a2818ee4SJoe Lawrence
callback_info(const char * callback,struct klp_object * obj)21*a2818ee4SJoe Lawrence static void callback_info(const char *callback, struct klp_object *obj)
22*a2818ee4SJoe Lawrence {
23*a2818ee4SJoe Lawrence if (obj->mod)
24*a2818ee4SJoe Lawrence pr_info("%s: %s -> %s\n", callback, obj->mod->name,
25*a2818ee4SJoe Lawrence module_state[obj->mod->state]);
26*a2818ee4SJoe Lawrence else
27*a2818ee4SJoe Lawrence pr_info("%s: vmlinux\n", callback);
28*a2818ee4SJoe Lawrence }
29*a2818ee4SJoe Lawrence
30*a2818ee4SJoe Lawrence /* Executed on object patching (ie, patch enablement) */
pre_patch_callback(struct klp_object * obj)31*a2818ee4SJoe Lawrence static int pre_patch_callback(struct klp_object *obj)
32*a2818ee4SJoe Lawrence {
33*a2818ee4SJoe Lawrence callback_info(__func__, obj);
34*a2818ee4SJoe Lawrence return pre_patch_ret;
35*a2818ee4SJoe Lawrence }
36*a2818ee4SJoe Lawrence
37*a2818ee4SJoe Lawrence /* Executed on object unpatching (ie, patch disablement) */
post_patch_callback(struct klp_object * obj)38*a2818ee4SJoe Lawrence static void post_patch_callback(struct klp_object *obj)
39*a2818ee4SJoe Lawrence {
40*a2818ee4SJoe Lawrence callback_info(__func__, obj);
41*a2818ee4SJoe Lawrence }
42*a2818ee4SJoe Lawrence
43*a2818ee4SJoe Lawrence /* Executed on object unpatching (ie, patch disablement) */
pre_unpatch_callback(struct klp_object * obj)44*a2818ee4SJoe Lawrence static void pre_unpatch_callback(struct klp_object *obj)
45*a2818ee4SJoe Lawrence {
46*a2818ee4SJoe Lawrence callback_info(__func__, obj);
47*a2818ee4SJoe Lawrence }
48*a2818ee4SJoe Lawrence
49*a2818ee4SJoe Lawrence /* Executed on object unpatching (ie, patch disablement) */
post_unpatch_callback(struct klp_object * obj)50*a2818ee4SJoe Lawrence static void post_unpatch_callback(struct klp_object *obj)
51*a2818ee4SJoe Lawrence {
52*a2818ee4SJoe Lawrence callback_info(__func__, obj);
53*a2818ee4SJoe Lawrence }
54*a2818ee4SJoe Lawrence
patched_work_func(struct work_struct * work)55*a2818ee4SJoe Lawrence static void patched_work_func(struct work_struct *work)
56*a2818ee4SJoe Lawrence {
57*a2818ee4SJoe Lawrence pr_info("%s\n", __func__);
58*a2818ee4SJoe Lawrence }
59*a2818ee4SJoe Lawrence
60*a2818ee4SJoe Lawrence static struct klp_func no_funcs[] = {
61*a2818ee4SJoe Lawrence {}
62*a2818ee4SJoe Lawrence };
63*a2818ee4SJoe Lawrence
64*a2818ee4SJoe Lawrence static struct klp_func busymod_funcs[] = {
65*a2818ee4SJoe Lawrence {
66*a2818ee4SJoe Lawrence .old_name = "busymod_work_func",
67*a2818ee4SJoe Lawrence .new_func = patched_work_func,
68*a2818ee4SJoe Lawrence }, {}
69*a2818ee4SJoe Lawrence };
70*a2818ee4SJoe Lawrence
71*a2818ee4SJoe Lawrence static struct klp_object objs[] = {
72*a2818ee4SJoe Lawrence {
73*a2818ee4SJoe Lawrence .name = NULL, /* vmlinux */
74*a2818ee4SJoe Lawrence .funcs = no_funcs,
75*a2818ee4SJoe Lawrence .callbacks = {
76*a2818ee4SJoe Lawrence .pre_patch = pre_patch_callback,
77*a2818ee4SJoe Lawrence .post_patch = post_patch_callback,
78*a2818ee4SJoe Lawrence .pre_unpatch = pre_unpatch_callback,
79*a2818ee4SJoe Lawrence .post_unpatch = post_unpatch_callback,
80*a2818ee4SJoe Lawrence },
81*a2818ee4SJoe Lawrence }, {
82*a2818ee4SJoe Lawrence .name = "test_klp_callbacks_mod",
83*a2818ee4SJoe Lawrence .funcs = no_funcs,
84*a2818ee4SJoe Lawrence .callbacks = {
85*a2818ee4SJoe Lawrence .pre_patch = pre_patch_callback,
86*a2818ee4SJoe Lawrence .post_patch = post_patch_callback,
87*a2818ee4SJoe Lawrence .pre_unpatch = pre_unpatch_callback,
88*a2818ee4SJoe Lawrence .post_unpatch = post_unpatch_callback,
89*a2818ee4SJoe Lawrence },
90*a2818ee4SJoe Lawrence }, {
91*a2818ee4SJoe Lawrence .name = "test_klp_callbacks_busy",
92*a2818ee4SJoe Lawrence .funcs = busymod_funcs,
93*a2818ee4SJoe Lawrence .callbacks = {
94*a2818ee4SJoe Lawrence .pre_patch = pre_patch_callback,
95*a2818ee4SJoe Lawrence .post_patch = post_patch_callback,
96*a2818ee4SJoe Lawrence .pre_unpatch = pre_unpatch_callback,
97*a2818ee4SJoe Lawrence .post_unpatch = post_unpatch_callback,
98*a2818ee4SJoe Lawrence },
99*a2818ee4SJoe Lawrence }, { }
100*a2818ee4SJoe Lawrence };
101*a2818ee4SJoe Lawrence
102*a2818ee4SJoe Lawrence static struct klp_patch patch = {
103*a2818ee4SJoe Lawrence .mod = THIS_MODULE,
104*a2818ee4SJoe Lawrence .objs = objs,
105*a2818ee4SJoe Lawrence };
106*a2818ee4SJoe Lawrence
test_klp_callbacks_demo_init(void)107*a2818ee4SJoe Lawrence static int test_klp_callbacks_demo_init(void)
108*a2818ee4SJoe Lawrence {
109*a2818ee4SJoe Lawrence return klp_enable_patch(&patch);
110*a2818ee4SJoe Lawrence }
111*a2818ee4SJoe Lawrence
test_klp_callbacks_demo_exit(void)112*a2818ee4SJoe Lawrence static void test_klp_callbacks_demo_exit(void)
113*a2818ee4SJoe Lawrence {
114*a2818ee4SJoe Lawrence }
115*a2818ee4SJoe Lawrence
116*a2818ee4SJoe Lawrence module_init(test_klp_callbacks_demo_init);
117*a2818ee4SJoe Lawrence module_exit(test_klp_callbacks_demo_exit);
118*a2818ee4SJoe Lawrence MODULE_LICENSE("GPL");
119*a2818ee4SJoe Lawrence MODULE_INFO(livepatch, "Y");
120*a2818ee4SJoe Lawrence MODULE_AUTHOR("Joe Lawrence <joe.lawrence@redhat.com>");
121*a2818ee4SJoe Lawrence MODULE_DESCRIPTION("Livepatch test: livepatch demo");
122