25 #include "patch.h"
70 	 * Note that the patch might still be needed before klp_module_going()  in klp_find_object_module()
101 static struct klp_object *klp_find_object(struct klp_patch *patch,  in klp_find_object()  argument
106 	klp_for_each_object(patch, obj) {  in klp_find_object()
323  * /sys/kernel/livepatch/<patch>
324  * /sys/kernel/livepatch/<patch>/enabled
325  * /sys/kernel/livepatch/<patch>/transition
326  * /sys/kernel/livepatch/<patch>/force
327  * /sys/kernel/livepatch/<patch>/<object>
328  * /sys/kernel/livepatch/<patch>/<object>/patched
329  * /sys/kernel/livepatch/<patch>/<object>/<function,sympos>
331 static int __klp_disable_patch(struct klp_patch *patch);
336 	struct klp_patch *patch;  in enabled_store()  local
344 	patch = container_of(kobj, struct klp_patch, kobj);  in enabled_store()
348 	if (patch->enabled == enabled) {  in enabled_store()
359 	 * Do not allow to re-enable a disabled patch.  in enabled_store()
361 	if (patch == klp_transition_patch)  in enabled_store()
364 		ret = __klp_disable_patch(patch);  in enabled_store()
379 	struct klp_patch *patch;  in enabled_show()  local
381 	patch = container_of(kobj, struct klp_patch, kobj);  in enabled_show()
382 	return snprintf(buf, PAGE_SIZE-1, "%d\n", patch->enabled);  in enabled_show()
388 	struct klp_patch *patch;  in transition_show()  local
390 	patch = container_of(kobj, struct klp_patch, kobj);  in transition_show()
392 			patch == klp_transition_patch);  in transition_show()
398 	struct klp_patch *patch;  in force_store()  local
411 	patch = container_of(kobj, struct klp_patch, kobj);  in force_store()
412 	if (patch != klp_transition_patch) {  in force_store()
459 static void klp_init_object_early(struct klp_patch *patch,
463 						   struct klp_patch *patch)  in klp_alloc_object_dynamic()  argument
479 	klp_init_object_early(patch, obj);  in klp_alloc_object_dynamic()
519 static int klp_add_object_nops(struct klp_patch *patch,  in klp_add_object_nops()  argument
525 	obj = klp_find_object(patch, old_obj);  in klp_add_object_nops()
528 		obj = klp_alloc_object_dynamic(old_obj->name, patch);  in klp_add_object_nops()
549  * patch to facilitate a 'replace' mode.
551 static int klp_add_nops(struct klp_patch *patch)  in klp_add_nops()  argument
560 			err = klp_add_object_nops(patch, old_obj);  in klp_add_nops()
571 	struct klp_patch *patch;  in klp_kobj_release_patch()  local
573 	patch = container_of(kobj, struct klp_patch, kobj);  in klp_kobj_release_patch()
574 	complete(&patch->finish);  in klp_kobj_release_patch()
642 static void __klp_free_objects(struct klp_patch *patch, bool nops_only)  in __klp_free_objects()  argument
646 	klp_for_each_object_safe(patch, obj, tmp_obj) {  in __klp_free_objects()
657 static void klp_free_objects(struct klp_patch *patch)  in klp_free_objects()  argument
659 	__klp_free_objects(patch, false);  in klp_free_objects()
662 static void klp_free_objects_dynamic(struct klp_patch *patch)  in klp_free_objects_dynamic()  argument
664 	__klp_free_objects(patch, true);  in klp_free_objects_dynamic()
674 static void klp_free_patch_start(struct klp_patch *patch)  in klp_free_patch_start()  argument
676 	if (!list_empty(&patch->list))  in klp_free_patch_start()
677 		list_del(&patch->list);  in klp_free_patch_start()
679 	klp_free_objects(patch);  in klp_free_patch_start()
687  * the last function accessing the livepatch structures when the patch
690 static void klp_free_patch_finish(struct klp_patch *patch)  in klp_free_patch_finish()  argument
695 	 * this is called when the patch gets disabled and it  in klp_free_patch_finish()
698 	kobject_put(&patch->kobj);  in klp_free_patch_finish()
699 	wait_for_completion(&patch->finish);  in klp_free_patch_finish()
702 	if (!patch->forced)  in klp_free_patch_finish()
703 		module_put(patch->mod);  in klp_free_patch_finish()
707  * The livepatch might be freed from sysfs interface created by the patch.
713 	struct klp_patch *patch =  in klp_free_patch_work_fn()  local
716 	klp_free_patch_finish(patch);  in klp_free_patch_work_fn()
719 void klp_free_patch_async(struct klp_patch *patch)  in klp_free_patch_async()  argument
721 	klp_free_patch_start(patch);  in klp_free_patch_async()
722 	schedule_work(&patch->free_work);  in klp_free_patch_async()
765 static int klp_apply_object_relocs(struct klp_patch *patch,  in klp_apply_object_relocs()  argument
769 	struct klp_modinfo *info = patch->mod->klp_info;  in klp_apply_object_relocs()
777 		ret = klp_apply_section_relocs(patch->mod, info->sechdrs,  in klp_apply_object_relocs()
779 					       patch->mod->core_kallsyms.strtab,  in klp_apply_object_relocs()
789 static int klp_init_object_loaded(struct klp_patch *patch,  in klp_init_object_loaded()  argument
802 		ret = klp_apply_object_relocs(patch, obj);  in klp_init_object_loaded()
837 static int klp_init_object(struct klp_patch *patch, struct klp_object *obj)  in klp_init_object()  argument
852 	ret = kobject_add(&obj->kobj, &patch->kobj, "%s", name);  in klp_init_object()
863 		ret = klp_init_object_loaded(patch, obj);  in klp_init_object()
875 static void klp_init_object_early(struct klp_patch *patch,  in klp_init_object_early()  argument
880 	list_add_tail(&obj->node, &patch->obj_list);  in klp_init_object_early()
883 static void klp_init_patch_early(struct klp_patch *patch)  in klp_init_patch_early()  argument
888 	INIT_LIST_HEAD(&patch->list);  in klp_init_patch_early()
889 	INIT_LIST_HEAD(&patch->obj_list);  in klp_init_patch_early()
890 	kobject_init(&patch->kobj, &klp_ktype_patch);  in klp_init_patch_early()
891 	patch->enabled = false;  in klp_init_patch_early()
892 	patch->forced = false;  in klp_init_patch_early()
893 	INIT_WORK(&patch->free_work, klp_free_patch_work_fn);  in klp_init_patch_early()
894 	init_completion(&patch->finish);  in klp_init_patch_early()
896 	klp_for_each_object_static(patch, obj) {  in klp_init_patch_early()
897 		klp_init_object_early(patch, obj);  in klp_init_patch_early()
905 static int klp_init_patch(struct klp_patch *patch)  in klp_init_patch()  argument
910 	ret = kobject_add(&patch->kobj, klp_root_kobj, "%s", patch->mod->name);  in klp_init_patch()
914 	if (patch->replace) {  in klp_init_patch()
915 		ret = klp_add_nops(patch);  in klp_init_patch()
920 	klp_for_each_object(patch, obj) {  in klp_init_patch()
921 		ret = klp_init_object(patch, obj);  in klp_init_patch()
926 	list_add_tail(&patch->list, &klp_patches);  in klp_init_patch()
931 static int __klp_disable_patch(struct klp_patch *patch)  in __klp_disable_patch()  argument
935 	if (WARN_ON(!patch->enabled))  in __klp_disable_patch()
941 	klp_init_transition(patch, KLP_UNPATCHED);  in __klp_disable_patch()
943 	klp_for_each_object(patch, obj)  in __klp_disable_patch()
957 	patch->enabled = false;  in __klp_disable_patch()
963 static int __klp_enable_patch(struct klp_patch *patch)  in __klp_enable_patch()  argument
971 	if (WARN_ON(patch->enabled))  in __klp_enable_patch()
974 	pr_notice("enabling patch '%s'\n", patch->mod->name);  in __klp_enable_patch()
976 	klp_init_transition(patch, KLP_PATCHED);  in __klp_enable_patch()
987 	klp_for_each_object(patch, obj) {  in __klp_enable_patch()
993 			pr_warn("pre-patch callback failed for object '%s'\n",  in __klp_enable_patch()
1000 			pr_warn("failed to patch object '%s'\n",  in __klp_enable_patch()
1007 	patch->enabled = true;  in __klp_enable_patch()
1012 	pr_warn("failed to enable patch '%s'\n", patch->mod->name);  in __klp_enable_patch()
1020  * @patch:	patch to be enabled
1022  * Initializes the data structure associated with the patch, creates the sysfs
1031 int klp_enable_patch(struct klp_patch *patch)  in klp_enable_patch()  argument
1036 	if (!patch || !patch->mod || !patch->objs)  in klp_enable_patch()
1039 	klp_for_each_object_static(patch, obj) {  in klp_enable_patch()
1045 	if (!is_livepatch_module(patch->mod)) {  in klp_enable_patch()
1047 		       patch->mod->name);  in klp_enable_patch()
1061 	if (!klp_is_patch_compatible(patch)) {  in klp_enable_patch()
1062 		pr_err("Livepatch patch (%s) is not compatible with the already installed livepatches.\n",  in klp_enable_patch()
1063 			patch->mod->name);  in klp_enable_patch()
1068 	if (!try_module_get(patch->mod)) {  in klp_enable_patch()
1073 	klp_init_patch_early(patch);  in klp_enable_patch()
1075 	ret = klp_init_patch(patch);  in klp_enable_patch()
1079 	ret = __klp_enable_patch(patch);  in klp_enable_patch()
1088 	klp_free_patch_start(patch);  in klp_enable_patch()
1092 	klp_free_patch_finish(patch);  in klp_enable_patch()
1108  * klp_ftrace_handler() might still see the replaced patch on the stack.
1111  * this is handled transparently by patch->module_put.
1156 	struct klp_patch *patch;  in klp_cleanup_module_patches_limited()  local
1159 	klp_for_each_patch(patch) {  in klp_cleanup_module_patches_limited()
1160 		if (patch == limit)  in klp_cleanup_module_patches_limited()
1163 		klp_for_each_object(patch, obj) {  in klp_cleanup_module_patches_limited()
1167 			if (patch != klp_transition_patch)  in klp_cleanup_module_patches_limited()
1170 			pr_notice("reverting patch '%s' on unloading module '%s'\n",  in klp_cleanup_module_patches_limited()
1171 				  patch->mod->name, obj->mod->name);  in klp_cleanup_module_patches_limited()
1185 	struct klp_patch *patch;  in klp_module_coming()  local
1200 	 * get patched by a new patch.  in klp_module_coming()
1204 	klp_for_each_patch(patch) {  in klp_module_coming()
1205 		klp_for_each_object(patch, obj) {  in klp_module_coming()
1211 			ret = klp_init_object_loaded(patch, obj);  in klp_module_coming()
1213 				pr_warn("failed to initialize patch '%s' for module '%s' (%d)\n",  in klp_module_coming()
1214 					patch->mod->name, obj->mod->name, ret);  in klp_module_coming()
1218 			pr_notice("applying patch '%s' to loading module '%s'\n",  in klp_module_coming()
1219 				  patch->mod->name, obj->mod->name);  in klp_module_coming()
1223 				pr_warn("pre-patch callback failed for object '%s'\n",  in klp_module_coming()
1230 				pr_warn("failed to apply patch '%s' to module '%s' (%d)\n",  in klp_module_coming()
1231 					patch->mod->name, obj->mod->name, ret);  in klp_module_coming()
1237 			if (patch != klp_transition_patch)  in klp_module_coming()
1250 	 * If a patch is unsuccessfully applied, return  in klp_module_coming()
1253 	pr_warn("patch '%s' failed for module '%s', refusing to load module '%s'\n",  in klp_module_coming()
1254 		patch->mod->name, obj->mod->name, obj->mod->name);  in klp_module_coming()
1257 	klp_cleanup_module_patches_limited(mod, patch);  in klp_module_coming()
1273 	 * get patched by a new patch.  in klp_module_going()