Root/
1 | /* |
2 | * security/tomoyo/memory.c |
3 | * |
4 | * Memory management functions for TOMOYO. |
5 | * |
6 | * Copyright (C) 2005-2010 NTT DATA CORPORATION |
7 | */ |
8 | |
9 | #include <linux/hash.h> |
10 | #include <linux/slab.h> |
11 | #include "common.h" |
12 | |
13 | /** |
14 | * tomoyo_warn_oom - Print out of memory warning message. |
15 | * |
16 | * @function: Function's name. |
17 | */ |
18 | void tomoyo_warn_oom(const char *function) |
19 | { |
20 | /* Reduce error messages. */ |
21 | static pid_t tomoyo_last_pid; |
22 | const pid_t pid = current->pid; |
23 | if (tomoyo_last_pid != pid) { |
24 | printk(KERN_WARNING "ERROR: Out of memory at %s.\n", |
25 | function); |
26 | tomoyo_last_pid = pid; |
27 | } |
28 | if (!tomoyo_policy_loaded) |
29 | panic("MAC Initialization failed.\n"); |
30 | } |
31 | |
32 | /* Memory allocated for policy. */ |
33 | static atomic_t tomoyo_policy_memory_size; |
34 | /* Quota for holding policy. */ |
35 | static unsigned int tomoyo_quota_for_policy; |
36 | |
37 | /** |
38 | * tomoyo_memory_ok - Check memory quota. |
39 | * |
40 | * @ptr: Pointer to allocated memory. |
41 | * |
42 | * Returns true on success, false otherwise. |
43 | * |
44 | * Returns true if @ptr is not NULL and quota not exceeded, false otherwise. |
45 | */ |
46 | bool tomoyo_memory_ok(void *ptr) |
47 | { |
48 | size_t s = ptr ? ksize(ptr) : 0; |
49 | atomic_add(s, &tomoyo_policy_memory_size); |
50 | if (ptr && (!tomoyo_quota_for_policy || |
51 | atomic_read(&tomoyo_policy_memory_size) |
52 | <= tomoyo_quota_for_policy)) { |
53 | memset(ptr, 0, s); |
54 | return true; |
55 | } |
56 | atomic_sub(s, &tomoyo_policy_memory_size); |
57 | tomoyo_warn_oom(__func__); |
58 | return false; |
59 | } |
60 | |
61 | /** |
62 | * tomoyo_commit_ok - Check memory quota. |
63 | * |
64 | * @data: Data to copy from. |
65 | * @size: Size in byte. |
66 | * |
67 | * Returns pointer to allocated memory on success, NULL otherwise. |
68 | * @data is zero-cleared on success. |
69 | */ |
70 | void *tomoyo_commit_ok(void *data, const unsigned int size) |
71 | { |
72 | void *ptr = kzalloc(size, GFP_NOFS); |
73 | if (tomoyo_memory_ok(ptr)) { |
74 | memmove(ptr, data, size); |
75 | memset(data, 0, size); |
76 | return ptr; |
77 | } |
78 | kfree(ptr); |
79 | return NULL; |
80 | } |
81 | |
82 | /** |
83 | * tomoyo_memory_free - Free memory for elements. |
84 | * |
85 | * @ptr: Pointer to allocated memory. |
86 | */ |
87 | void tomoyo_memory_free(void *ptr) |
88 | { |
89 | atomic_sub(ksize(ptr), &tomoyo_policy_memory_size); |
90 | kfree(ptr); |
91 | } |
92 | |
93 | /** |
94 | * tomoyo_get_group - Allocate memory for "struct tomoyo_path_group"/"struct tomoyo_number_group". |
95 | * |
96 | * @group_name: The name of address group. |
97 | * @idx: Index number. |
98 | * |
99 | * Returns pointer to "struct tomoyo_group" on success, NULL otherwise. |
100 | */ |
101 | struct tomoyo_group *tomoyo_get_group(const char *group_name, const u8 idx) |
102 | { |
103 | struct tomoyo_group e = { }; |
104 | struct tomoyo_group *group = NULL; |
105 | bool found = false; |
106 | if (!tomoyo_correct_word(group_name) || idx >= TOMOYO_MAX_GROUP) |
107 | return NULL; |
108 | e.group_name = tomoyo_get_name(group_name); |
109 | if (!e.group_name) |
110 | return NULL; |
111 | if (mutex_lock_interruptible(&tomoyo_policy_lock)) |
112 | goto out; |
113 | list_for_each_entry(group, &tomoyo_group_list[idx], list) { |
114 | if (e.group_name != group->group_name) |
115 | continue; |
116 | atomic_inc(&group->users); |
117 | found = true; |
118 | break; |
119 | } |
120 | if (!found) { |
121 | struct tomoyo_group *entry = tomoyo_commit_ok(&e, sizeof(e)); |
122 | if (entry) { |
123 | INIT_LIST_HEAD(&entry->member_list); |
124 | atomic_set(&entry->users, 1); |
125 | list_add_tail_rcu(&entry->list, |
126 | &tomoyo_group_list[idx]); |
127 | group = entry; |
128 | found = true; |
129 | } |
130 | } |
131 | mutex_unlock(&tomoyo_policy_lock); |
132 | out: |
133 | tomoyo_put_name(e.group_name); |
134 | return found ? group : NULL; |
135 | } |
136 | |
137 | /* |
138 | * tomoyo_name_list is used for holding string data used by TOMOYO. |
139 | * Since same string data is likely used for multiple times (e.g. |
140 | * "/lib/libc-2.5.so"), TOMOYO shares string data in the form of |
141 | * "const struct tomoyo_path_info *". |
142 | */ |
143 | struct list_head tomoyo_name_list[TOMOYO_MAX_HASH]; |
144 | |
145 | /** |
146 | * tomoyo_get_name - Allocate permanent memory for string data. |
147 | * |
148 | * @name: The string to store into the permernent memory. |
149 | * |
150 | * Returns pointer to "struct tomoyo_path_info" on success, NULL otherwise. |
151 | */ |
152 | const struct tomoyo_path_info *tomoyo_get_name(const char *name) |
153 | { |
154 | struct tomoyo_name *ptr; |
155 | unsigned int hash; |
156 | int len; |
157 | int allocated_len; |
158 | struct list_head *head; |
159 | |
160 | if (!name) |
161 | return NULL; |
162 | len = strlen(name) + 1; |
163 | hash = full_name_hash((const unsigned char *) name, len - 1); |
164 | head = &tomoyo_name_list[hash_long(hash, TOMOYO_HASH_BITS)]; |
165 | if (mutex_lock_interruptible(&tomoyo_policy_lock)) |
166 | return NULL; |
167 | list_for_each_entry(ptr, head, list) { |
168 | if (hash != ptr->entry.hash || strcmp(name, ptr->entry.name)) |
169 | continue; |
170 | atomic_inc(&ptr->users); |
171 | goto out; |
172 | } |
173 | ptr = kzalloc(sizeof(*ptr) + len, GFP_NOFS); |
174 | allocated_len = ptr ? ksize(ptr) : 0; |
175 | if (!ptr || (tomoyo_quota_for_policy && |
176 | atomic_read(&tomoyo_policy_memory_size) + allocated_len |
177 | > tomoyo_quota_for_policy)) { |
178 | kfree(ptr); |
179 | ptr = NULL; |
180 | tomoyo_warn_oom(__func__); |
181 | goto out; |
182 | } |
183 | atomic_add(allocated_len, &tomoyo_policy_memory_size); |
184 | ptr->entry.name = ((char *) ptr) + sizeof(*ptr); |
185 | memmove((char *) ptr->entry.name, name, len); |
186 | atomic_set(&ptr->users, 1); |
187 | tomoyo_fill_path_info(&ptr->entry); |
188 | list_add_tail(&ptr->list, head); |
189 | out: |
190 | mutex_unlock(&tomoyo_policy_lock); |
191 | return ptr ? &ptr->entry : NULL; |
192 | } |
193 | |
194 | /** |
195 | * tomoyo_mm_init - Initialize mm related code. |
196 | */ |
197 | void __init tomoyo_mm_init(void) |
198 | { |
199 | int idx; |
200 | |
201 | for (idx = 0; idx < TOMOYO_MAX_POLICY; idx++) |
202 | INIT_LIST_HEAD(&tomoyo_policy_list[idx]); |
203 | for (idx = 0; idx < TOMOYO_MAX_GROUP; idx++) |
204 | INIT_LIST_HEAD(&tomoyo_group_list[idx]); |
205 | for (idx = 0; idx < TOMOYO_MAX_HASH; idx++) |
206 | INIT_LIST_HEAD(&tomoyo_name_list[idx]); |
207 | INIT_LIST_HEAD(&tomoyo_kernel_domain.acl_info_list); |
208 | tomoyo_kernel_domain.domainname = tomoyo_get_name(TOMOYO_ROOT_NAME); |
209 | list_add_tail_rcu(&tomoyo_kernel_domain.list, &tomoyo_domain_list); |
210 | idx = tomoyo_read_lock(); |
211 | if (tomoyo_find_domain(TOMOYO_ROOT_NAME) != &tomoyo_kernel_domain) |
212 | panic("Can't register tomoyo_kernel_domain"); |
213 | { |
214 | /* Load built-in policy. */ |
215 | tomoyo_write_transition_control("/sbin/hotplug", false, |
216 | TOMOYO_TRANSITION_CONTROL_INITIALIZE); |
217 | tomoyo_write_transition_control("/sbin/modprobe", false, |
218 | TOMOYO_TRANSITION_CONTROL_INITIALIZE); |
219 | } |
220 | tomoyo_read_unlock(idx); |
221 | } |
222 | |
223 | |
224 | /* Memory allocated for query lists. */ |
225 | unsigned int tomoyo_query_memory_size; |
226 | /* Quota for holding query lists. */ |
227 | unsigned int tomoyo_quota_for_query; |
228 | |
229 | /** |
230 | * tomoyo_read_memory_counter - Check for memory usage in bytes. |
231 | * |
232 | * @head: Pointer to "struct tomoyo_io_buffer". |
233 | * |
234 | * Returns memory usage. |
235 | */ |
236 | void tomoyo_read_memory_counter(struct tomoyo_io_buffer *head) |
237 | { |
238 | if (!head->r.eof) { |
239 | const unsigned int policy |
240 | = atomic_read(&tomoyo_policy_memory_size); |
241 | const unsigned int query = tomoyo_query_memory_size; |
242 | char buffer[64]; |
243 | |
244 | memset(buffer, 0, sizeof(buffer)); |
245 | if (tomoyo_quota_for_policy) |
246 | snprintf(buffer, sizeof(buffer) - 1, |
247 | " (Quota: %10u)", |
248 | tomoyo_quota_for_policy); |
249 | else |
250 | buffer[0] = '\0'; |
251 | tomoyo_io_printf(head, "Policy: %10u%s\n", policy, |
252 | buffer); |
253 | if (tomoyo_quota_for_query) |
254 | snprintf(buffer, sizeof(buffer) - 1, |
255 | " (Quota: %10u)", |
256 | tomoyo_quota_for_query); |
257 | else |
258 | buffer[0] = '\0'; |
259 | tomoyo_io_printf(head, "Query lists: %10u%s\n", query, |
260 | buffer); |
261 | tomoyo_io_printf(head, "Total: %10u\n", policy + query); |
262 | head->r.eof = true; |
263 | } |
264 | } |
265 | |
266 | /** |
267 | * tomoyo_write_memory_quota - Set memory quota. |
268 | * |
269 | * @head: Pointer to "struct tomoyo_io_buffer". |
270 | * |
271 | * Returns 0. |
272 | */ |
273 | int tomoyo_write_memory_quota(struct tomoyo_io_buffer *head) |
274 | { |
275 | char *data = head->write_buf; |
276 | unsigned int size; |
277 | |
278 | if (sscanf(data, "Policy: %u", &size) == 1) |
279 | tomoyo_quota_for_policy = size; |
280 | else if (sscanf(data, "Query lists: %u", &size) == 1) |
281 | tomoyo_quota_for_query = size; |
282 | return 0; |
283 | } |
284 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9