| // SPDX-License-Identifier: GPL-2.0 |
| // Copyright (C) 2018 Joe Lawrence <joe.lawrence@redhat.com> |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/module.h> |
| #include <linux/kernel.h> |
| #include <linux/livepatch.h> |
| |
| static int pre_patch_ret; |
| module_param(pre_patch_ret, int, 0644); |
| MODULE_PARM_DESC(pre_patch_ret, "pre_patch_ret (default=0)"); |
| |
| static const char *const module_state[] = { |
| [MODULE_STATE_LIVE] = "[MODULE_STATE_LIVE] Normal state", |
| [MODULE_STATE_COMING] = "[MODULE_STATE_COMING] Full formed, running module_init", |
| [MODULE_STATE_GOING] = "[MODULE_STATE_GOING] Going away", |
| [MODULE_STATE_UNFORMED] = "[MODULE_STATE_UNFORMED] Still setting it up", |
| }; |
| |
| static void callback_info(const char *callback, struct klp_object *obj) |
| { |
| if (obj->mod) |
| pr_info("%s: %s -> %s\n", callback, obj->mod->name, |
| module_state[obj->mod->state]); |
| else |
| pr_info("%s: vmlinux\n", callback); |
| } |
| |
| /* Executed on object patching (ie, patch enablement) */ |
| static int pre_patch_callback(struct klp_object *obj) |
| { |
| callback_info(__func__, obj); |
| return pre_patch_ret; |
| } |
| |
| /* Executed on object unpatching (ie, patch disablement) */ |
| static void post_patch_callback(struct klp_object *obj) |
| { |
| callback_info(__func__, obj); |
| } |
| |
| /* Executed on object unpatching (ie, patch disablement) */ |
| static void pre_unpatch_callback(struct klp_object *obj) |
| { |
| callback_info(__func__, obj); |
| } |
| |
| /* Executed on object unpatching (ie, patch disablement) */ |
| static void post_unpatch_callback(struct klp_object *obj) |
| { |
| callback_info(__func__, obj); |
| } |
| |
| static void patched_work_func(struct work_struct *work) |
| { |
| pr_info("%s\n", __func__); |
| } |
| |
| static struct klp_func no_funcs[] = { |
| {} |
| }; |
| |
| static struct klp_func busymod_funcs[] = { |
| { |
| .old_name = "busymod_work_func", |
| .new_func = patched_work_func, |
| }, {} |
| }; |
| |
| static struct klp_object objs[] = { |
| { |
| .name = NULL, /* vmlinux */ |
| .funcs = no_funcs, |
| .callbacks = { |
| .pre_patch = pre_patch_callback, |
| .post_patch = post_patch_callback, |
| .pre_unpatch = pre_unpatch_callback, |
| .post_unpatch = post_unpatch_callback, |
| }, |
| }, { |
| .name = "test_klp_callbacks_mod", |
| .funcs = no_funcs, |
| .callbacks = { |
| .pre_patch = pre_patch_callback, |
| .post_patch = post_patch_callback, |
| .pre_unpatch = pre_unpatch_callback, |
| .post_unpatch = post_unpatch_callback, |
| }, |
| }, { |
| .name = "test_klp_callbacks_busy", |
| .funcs = busymod_funcs, |
| .callbacks = { |
| .pre_patch = pre_patch_callback, |
| .post_patch = post_patch_callback, |
| .pre_unpatch = pre_unpatch_callback, |
| .post_unpatch = post_unpatch_callback, |
| }, |
| }, { } |
| }; |
| |
| static struct klp_patch patch = { |
| .mod = THIS_MODULE, |
| .objs = objs, |
| }; |
| |
| static int test_klp_callbacks_demo_init(void) |
| { |
| return klp_enable_patch(&patch); |
| } |
| |
| static void test_klp_callbacks_demo_exit(void) |
| { |
| } |
| |
| module_init(test_klp_callbacks_demo_init); |
| module_exit(test_klp_callbacks_demo_exit); |
| MODULE_LICENSE("GPL"); |
| MODULE_INFO(livepatch, "Y"); |
| MODULE_AUTHOR("Joe Lawrence <joe.lawrence@redhat.com>"); |
| MODULE_DESCRIPTION("Livepatch test: livepatch demo"); |