~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/include/linux/livepatch.h

Version: ~ [ linux-4.15-rc3 ] ~ [ linux-4.14.5 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.68 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.105 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.47 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.87 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.51 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.96 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.39.4 ] ~ [ linux-2.6.38.8 ] ~ [ linux-2.6.37.6 ] ~ [ linux-2.6.36.4 ] ~ [ linux-2.6.35.14 ] ~ [ linux-2.6.34.15 ] ~ [ linux-2.6.33.20 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.27.62 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 /*
  2  * livepatch.h - Kernel Live Patching Core
  3  *
  4  * Copyright (C) 2014 Seth Jennings <sjenning@redhat.com>
  5  * Copyright (C) 2014 SUSE
  6  *
  7  * This program is free software; you can redistribute it and/or
  8  * modify it under the terms of the GNU General Public License
  9  * as published by the Free Software Foundation; either version 2
 10  * of the License, or (at your option) any later version.
 11  *
 12  * This program is distributed in the hope that it will be useful,
 13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
 14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 15  * GNU General Public License for more details.
 16  *
 17  * You should have received a copy of the GNU General Public License
 18  * along with this program; if not, see <http://www.gnu.org/licenses/>.
 19  */
 20 
 21 #ifndef _LINUX_LIVEPATCH_H_
 22 #define _LINUX_LIVEPATCH_H_
 23 
 24 #include <linux/module.h>
 25 #include <linux/ftrace.h>
 26 #include <linux/completion.h>
 27 
 28 #if IS_ENABLED(CONFIG_LIVEPATCH)
 29 
 30 #include <asm/livepatch.h>
 31 
 32 /* task patch states */
 33 #define KLP_UNDEFINED   -1
 34 #define KLP_UNPATCHED    0
 35 #define KLP_PATCHED      1
 36 
 37 /**
 38  * struct klp_func - function structure for live patching
 39  * @old_name:   name of the function to be patched
 40  * @new_func:   pointer to the patched function code
 41  * @old_sympos: a hint indicating which symbol position the old function
 42  *              can be found (optional)
 43  * @immediate:  patch the func immediately, bypassing safety mechanisms
 44  * @old_addr:   the address of the function being patched
 45  * @kobj:       kobject for sysfs resources
 46  * @stack_node: list node for klp_ops func_stack list
 47  * @old_size:   size of the old function
 48  * @new_size:   size of the new function
 49  * @patched:    the func has been added to the klp_ops list
 50  * @transition: the func is currently being applied or reverted
 51  *
 52  * The patched and transition variables define the func's patching state.  When
 53  * patching, a func is always in one of the following states:
 54  *
 55  *   patched=0 transition=0: unpatched
 56  *   patched=0 transition=1: unpatched, temporary starting state
 57  *   patched=1 transition=1: patched, may be visible to some tasks
 58  *   patched=1 transition=0: patched, visible to all tasks
 59  *
 60  * And when unpatching, it goes in the reverse order:
 61  *
 62  *   patched=1 transition=0: patched, visible to all tasks
 63  *   patched=1 transition=1: patched, may be visible to some tasks
 64  *   patched=0 transition=1: unpatched, temporary ending state
 65  *   patched=0 transition=0: unpatched
 66  */
 67 struct klp_func {
 68         /* external */
 69         const char *old_name;
 70         void *new_func;
 71         /*
 72          * The old_sympos field is optional and can be used to resolve
 73          * duplicate symbol names in livepatch objects. If this field is zero,
 74          * it is expected the symbol is unique, otherwise patching fails. If
 75          * this value is greater than zero then that occurrence of the symbol
 76          * in kallsyms for the given object is used.
 77          */
 78         unsigned long old_sympos;
 79         bool immediate;
 80 
 81         /* internal */
 82         unsigned long old_addr;
 83         struct kobject kobj;
 84         struct list_head stack_node;
 85         unsigned long old_size, new_size;
 86         bool patched;
 87         bool transition;
 88 };
 89 
 90 struct klp_object;
 91 
 92 /**
 93  * struct klp_callbacks - pre/post live-(un)patch callback structure
 94  * @pre_patch:          executed before code patching
 95  * @post_patch:         executed after code patching
 96  * @pre_unpatch:        executed before code unpatching
 97  * @post_unpatch:       executed after code unpatching
 98  * @post_unpatch_enabled:       flag indicating if post-unpatch callback
 99  *                              should run
100  *
101  * All callbacks are optional.  Only the pre-patch callback, if provided,
102  * will be unconditionally executed.  If the parent klp_object fails to
103  * patch for any reason, including a non-zero error status returned from
104  * the pre-patch callback, no further callbacks will be executed.
105  */
106 struct klp_callbacks {
107         int (*pre_patch)(struct klp_object *obj);
108         void (*post_patch)(struct klp_object *obj);
109         void (*pre_unpatch)(struct klp_object *obj);
110         void (*post_unpatch)(struct klp_object *obj);
111         bool post_unpatch_enabled;
112 };
113 
114 /**
115  * struct klp_object - kernel object structure for live patching
116  * @name:       module name (or NULL for vmlinux)
117  * @funcs:      function entries for functions to be patched in the object
118  * @callbacks:  functions to be executed pre/post (un)patching
119  * @kobj:       kobject for sysfs resources
120  * @mod:        kernel module associated with the patched object
121  *              (NULL for vmlinux)
122  * @patched:    the object's funcs have been added to the klp_ops list
123  */
124 struct klp_object {
125         /* external */
126         const char *name;
127         struct klp_func *funcs;
128         struct klp_callbacks callbacks;
129 
130         /* internal */
131         struct kobject kobj;
132         struct module *mod;
133         bool patched;
134 };
135 
136 /**
137  * struct klp_patch - patch structure for live patching
138  * @mod:        reference to the live patch module
139  * @objs:       object entries for kernel objects to be patched
140  * @immediate:  patch all funcs immediately, bypassing safety mechanisms
141  * @list:       list node for global list of registered patches
142  * @kobj:       kobject for sysfs resources
143  * @enabled:    the patch is enabled (but operation may be incomplete)
144  * @finish:     for waiting till it is safe to remove the patch module
145  */
146 struct klp_patch {
147         /* external */
148         struct module *mod;
149         struct klp_object *objs;
150         bool immediate;
151 
152         /* internal */
153         struct list_head list;
154         struct kobject kobj;
155         bool enabled;
156         struct completion finish;
157 };
158 
159 #define klp_for_each_object(patch, obj) \
160         for (obj = patch->objs; obj->funcs || obj->name; obj++)
161 
162 #define klp_for_each_func(obj, func) \
163         for (func = obj->funcs; \
164              func->old_name || func->new_func || func->old_sympos; \
165              func++)
166 
167 int klp_register_patch(struct klp_patch *);
168 int klp_unregister_patch(struct klp_patch *);
169 int klp_enable_patch(struct klp_patch *);
170 int klp_disable_patch(struct klp_patch *);
171 
172 void arch_klp_init_object_loaded(struct klp_patch *patch,
173                                  struct klp_object *obj);
174 
175 /* Called from the module loader during module coming/going states */
176 int klp_module_coming(struct module *mod);
177 void klp_module_going(struct module *mod);
178 
179 void klp_copy_process(struct task_struct *child);
180 void klp_update_patch_state(struct task_struct *task);
181 
182 static inline bool klp_patch_pending(struct task_struct *task)
183 {
184         return test_tsk_thread_flag(task, TIF_PATCH_PENDING);
185 }
186 
187 static inline bool klp_have_reliable_stack(void)
188 {
189         return IS_ENABLED(CONFIG_STACKTRACE) &&
190                IS_ENABLED(CONFIG_HAVE_RELIABLE_STACKTRACE);
191 }
192 
193 void *klp_shadow_get(void *obj, unsigned long id);
194 void *klp_shadow_alloc(void *obj, unsigned long id, void *data,
195                        size_t size, gfp_t gfp_flags);
196 void *klp_shadow_get_or_alloc(void *obj, unsigned long id, void *data,
197                               size_t size, gfp_t gfp_flags);
198 void klp_shadow_free(void *obj, unsigned long id);
199 void klp_shadow_free_all(unsigned long id);
200 
201 #else /* !CONFIG_LIVEPATCH */
202 
203 static inline int klp_module_coming(struct module *mod) { return 0; }
204 static inline void klp_module_going(struct module *mod) {}
205 static inline bool klp_patch_pending(struct task_struct *task) { return false; }
206 static inline void klp_update_patch_state(struct task_struct *task) {}
207 static inline void klp_copy_process(struct task_struct *child) {}
208 
209 #endif /* CONFIG_LIVEPATCH */
210 
211 #endif /* _LINUX_LIVEPATCH_H_ */
212 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp