diff options
-rw-r--r-- | arch/s390/Kconfig | 3 | ||||
-rw-r--r-- | arch/s390/include/asm/livepatch.h | 43 | ||||
-rw-r--r-- | arch/x86/include/asm/livepatch.h | 4 | ||||
-rw-r--r-- | include/linux/livepatch.h | 8 | ||||
-rw-r--r-- | kernel/livepatch/core.c | 69 |
5 files changed, 69 insertions, 58 deletions
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 373cd5b..b2d7ec1 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -133,6 +133,7 @@ config S390 select HAVE_KPROBES select HAVE_KRETPROBES select HAVE_KVM if 64BIT + select HAVE_LIVEPATCH select HAVE_MEMBLOCK select HAVE_MEMBLOCK_NODE_MAP select HAVE_MEMBLOCK_PHYS_MAP @@ -159,6 +160,8 @@ source "init/Kconfig" source "kernel/Kconfig.freezer" +source "kernel/livepatch/Kconfig" + menu "Processor type and features" config HAVE_MARCH_Z900_FEATURES diff --git a/arch/s390/include/asm/livepatch.h b/arch/s390/include/asm/livepatch.h new file mode 100644 index 0000000..7aa7991 --- /dev/null +++ b/arch/s390/include/asm/livepatch.h @@ -0,0 +1,43 @@ +/* + * livepatch.h - s390-specific Kernel Live Patching Core + * + * Copyright (c) 2013-2015 SUSE + * Authors: Jiri Kosina + * Vojtech Pavlik + * Jiri Slaby + */ + +/* + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the Free + * Software Foundation; either version 2 of the License, or (at your option) + * any later version. + */ + +#ifndef ASM_LIVEPATCH_H +#define ASM_LIVEPATCH_H + +#include <linux/module.h> + +#ifdef CONFIG_LIVEPATCH +static inline int klp_check_compiler_support(void) +{ + return 0; +} + +static inline int klp_write_module_reloc(struct module *mod, unsigned long + type, unsigned long loc, unsigned long value) +{ + /* not supported yet */ + return -ENOSYS; +} + +static inline void klp_arch_set_pc(struct pt_regs *regs, unsigned long ip) +{ + regs->psw.addr = ip; +} +#else +#error Live patching support is disabled; check CONFIG_LIVEPATCH +#endif + +#endif diff --git a/arch/x86/include/asm/livepatch.h b/arch/x86/include/asm/livepatch.h index a455a53..2d29197 100644 --- a/arch/x86/include/asm/livepatch.h +++ b/arch/x86/include/asm/livepatch.h @@ -32,8 +32,8 @@ static inline int klp_check_compiler_support(void) #endif return 0; } -extern int klp_write_module_reloc(struct module *mod, unsigned long type, - unsigned long loc, unsigned long value); +int klp_write_module_reloc(struct module *mod, unsigned long type, + unsigned long loc, unsigned long value); static inline void klp_arch_set_pc(struct pt_regs *regs, unsigned long ip) { diff --git a/include/linux/livepatch.h b/include/linux/livepatch.h index 95023fd..ee6dbb3 100644 --- a/include/linux/livepatch.h +++ b/include/linux/livepatch.h @@ -123,10 +123,10 @@ struct klp_patch { enum klp_state state; }; -extern int klp_register_patch(struct klp_patch *); -extern int klp_unregister_patch(struct klp_patch *); -extern int klp_enable_patch(struct klp_patch *); -extern int klp_disable_patch(struct klp_patch *); +int klp_register_patch(struct klp_patch *); +int klp_unregister_patch(struct klp_patch *); +int klp_enable_patch(struct klp_patch *); +int klp_disable_patch(struct klp_patch *); #endif /* CONFIG_LIVEPATCH */ diff --git a/kernel/livepatch/core.c b/kernel/livepatch/core.c index 3f9f1d6..284e269 100644 --- a/kernel/livepatch/core.c +++ b/kernel/livepatch/core.c @@ -335,32 +335,20 @@ unlock: rcu_read_unlock(); } -static int klp_disable_func(struct klp_func *func) +static void klp_disable_func(struct klp_func *func) { struct klp_ops *ops; - int ret; - - if (WARN_ON(func->state != KLP_ENABLED)) - return -EINVAL; - if (WARN_ON(!func->old_addr)) - return -EINVAL; + WARN_ON(func->state != KLP_ENABLED); + WARN_ON(!func->old_addr); ops = klp_find_ops(func->old_addr); if (WARN_ON(!ops)) - return -EINVAL; + return; if (list_is_singular(&ops->func_stack)) { - ret = unregister_ftrace_function(&ops->fops); - if (ret) { - pr_err("failed to unregister ftrace handler for function '%s' (%d)\n", - func->old_name, ret); - return ret; - } - - ret = ftrace_set_filter_ip(&ops->fops, func->old_addr, 1, 0); - if (ret) - pr_warn("function unregister succeeded but failed to clear the filter\n"); + WARN_ON(unregister_ftrace_function(&ops->fops)); + WARN_ON(ftrace_set_filter_ip(&ops->fops, func->old_addr, 1, 0)); list_del_rcu(&func->stack_node); list_del(&ops->node); @@ -370,8 +358,6 @@ static int klp_disable_func(struct klp_func *func) } func->state = KLP_DISABLED; - - return 0; } static int klp_enable_func(struct klp_func *func) @@ -432,23 +418,15 @@ err: return ret; } -static int klp_disable_object(struct klp_object *obj) +static void klp_disable_object(struct klp_object *obj) { struct klp_func *func; - int ret; - for (func = obj->funcs; func->old_name; func++) { - if (func->state != KLP_ENABLED) - continue; - - ret = klp_disable_func(func); - if (ret) - return ret; - } + for (func = obj->funcs; func->old_name; func++) + if (func->state == KLP_ENABLED) + klp_disable_func(func); obj->state = KLP_DISABLED; - - return 0; } static int klp_enable_object(struct klp_object *obj) @@ -464,22 +442,19 @@ static int klp_enable_object(struct klp_object *obj) for (func = obj->funcs; func->old_name; func++) { ret = klp_enable_func(func); - if (ret) - goto unregister; + if (ret) { + klp_disable_object(obj); + return ret; + } } obj->state = KLP_ENABLED; return 0; - -unregister: - WARN_ON(klp_disable_object(obj)); - return ret; } static int __klp_disable_patch(struct klp_patch *patch) { struct klp_object *obj; - int ret; /* enforce stacking: only the last enabled patch can be disabled */ if (!list_is_last(&patch->list, &klp_patches) && @@ -489,12 +464,8 @@ static int __klp_disable_patch(struct klp_patch *patch) pr_notice("disabling patch '%s'\n", patch->mod->name); for (obj = patch->objs; obj->funcs; obj++) { - if (obj->state != KLP_ENABLED) - continue; - - ret = klp_disable_object(obj); - if (ret) - return ret; + if (obj->state == KLP_ENABLED) + klp_disable_object(obj); } patch->state = KLP_DISABLED; @@ -553,8 +524,6 @@ static int __klp_enable_patch(struct klp_patch *patch) pr_notice("enabling patch '%s'\n", patch->mod->name); for (obj = patch->objs; obj->funcs; obj++) { - klp_find_object_module(obj); - if (!klp_is_object_loaded(obj)) continue; @@ -945,7 +914,6 @@ static void klp_module_notify_going(struct klp_patch *patch, { struct module *pmod = patch->mod; struct module *mod = obj->mod; - int ret; if (patch->state == KLP_DISABLED) goto disabled; @@ -953,10 +921,7 @@ static void klp_module_notify_going(struct klp_patch *patch, pr_notice("reverting patch '%s' on unloading module '%s'\n", pmod->name, mod->name); - ret = klp_disable_object(obj); - if (ret) - pr_warn("failed to revert patch '%s' on module '%s' (%d)\n", - pmod->name, mod->name, ret); + klp_disable_object(obj); disabled: klp_free_object_loaded(obj); |