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7#include <linux/slab.h>
8#include "common.h"
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13#define TOMOYO_MOUNT_BIND_KEYWORD "--bind"
14
15#define TOMOYO_MOUNT_MOVE_KEYWORD "--move"
16
17#define TOMOYO_MOUNT_REMOUNT_KEYWORD "--remount"
18
19#define TOMOYO_MOUNT_MAKE_UNBINDABLE_KEYWORD "--make-unbindable"
20
21#define TOMOYO_MOUNT_MAKE_PRIVATE_KEYWORD "--make-private"
22
23#define TOMOYO_MOUNT_MAKE_SLAVE_KEYWORD "--make-slave"
24
25#define TOMOYO_MOUNT_MAKE_SHARED_KEYWORD "--make-shared"
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33
34static int tomoyo_audit_mount_log(struct tomoyo_request_info *r)
35{
36 const char *dev = r->param.mount.dev->name;
37 const char *dir = r->param.mount.dir->name;
38 const char *type = r->param.mount.type->name;
39 const unsigned long flags = r->param.mount.flags;
40 if (r->granted)
41 return 0;
42 if (!strcmp(type, TOMOYO_MOUNT_REMOUNT_KEYWORD))
43 tomoyo_warn_log(r, "mount -o remount %s 0x%lX", dir, flags);
44 else if (!strcmp(type, TOMOYO_MOUNT_BIND_KEYWORD)
45 || !strcmp(type, TOMOYO_MOUNT_MOVE_KEYWORD))
46 tomoyo_warn_log(r, "mount %s %s %s 0x%lX", type, dev, dir,
47 flags);
48 else if (!strcmp(type, TOMOYO_MOUNT_MAKE_UNBINDABLE_KEYWORD) ||
49 !strcmp(type, TOMOYO_MOUNT_MAKE_PRIVATE_KEYWORD) ||
50 !strcmp(type, TOMOYO_MOUNT_MAKE_SLAVE_KEYWORD) ||
51 !strcmp(type, TOMOYO_MOUNT_MAKE_SHARED_KEYWORD))
52 tomoyo_warn_log(r, "mount %s %s 0x%lX", type, dir, flags);
53 else
54 tomoyo_warn_log(r, "mount -t %s %s %s 0x%lX", type, dev, dir,
55 flags);
56 return tomoyo_supervisor(r,
57 TOMOYO_KEYWORD_ALLOW_MOUNT "%s %s %s 0x%lX\n",
58 tomoyo_pattern(r->param.mount.dev),
59 tomoyo_pattern(r->param.mount.dir), type,
60 flags);
61}
62
63static bool tomoyo_check_mount_acl(struct tomoyo_request_info *r,
64 const struct tomoyo_acl_info *ptr)
65{
66 const struct tomoyo_mount_acl *acl =
67 container_of(ptr, typeof(*acl), head);
68 return tomoyo_compare_number_union(r->param.mount.flags, &acl->flags) &&
69 tomoyo_compare_name_union(r->param.mount.type, &acl->fs_type) &&
70 tomoyo_compare_name_union(r->param.mount.dir, &acl->dir_name) &&
71 (!r->param.mount.need_dev ||
72 tomoyo_compare_name_union(r->param.mount.dev, &acl->dev_name));
73}
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88static int tomoyo_mount_acl(struct tomoyo_request_info *r, char *dev_name,
89 struct path *dir, char *type, unsigned long flags)
90{
91 struct path path;
92 struct file_system_type *fstype = NULL;
93 const char *requested_type = NULL;
94 const char *requested_dir_name = NULL;
95 const char *requested_dev_name = NULL;
96 struct tomoyo_path_info rtype;
97 struct tomoyo_path_info rdev;
98 struct tomoyo_path_info rdir;
99 int need_dev = 0;
100 int error = -ENOMEM;
101
102
103 requested_type = tomoyo_encode(type);
104 if (!requested_type)
105 goto out;
106 rtype.name = requested_type;
107 tomoyo_fill_path_info(&rtype);
108
109
110 requested_dir_name = tomoyo_realpath_from_path(dir);
111 if (!requested_dir_name) {
112 error = -ENOMEM;
113 goto out;
114 }
115 rdir.name = requested_dir_name;
116 tomoyo_fill_path_info(&rdir);
117
118
119 if (!strcmp(type, TOMOYO_MOUNT_REMOUNT_KEYWORD)) {
120
121 } else if (!strcmp(type, TOMOYO_MOUNT_MAKE_UNBINDABLE_KEYWORD) ||
122 !strcmp(type, TOMOYO_MOUNT_MAKE_PRIVATE_KEYWORD) ||
123 !strcmp(type, TOMOYO_MOUNT_MAKE_SLAVE_KEYWORD) ||
124 !strcmp(type, TOMOYO_MOUNT_MAKE_SHARED_KEYWORD)) {
125
126 } else if (!strcmp(type, TOMOYO_MOUNT_BIND_KEYWORD) ||
127 !strcmp(type, TOMOYO_MOUNT_MOVE_KEYWORD)) {
128 need_dev = -1;
129 } else {
130 fstype = get_fs_type(type);
131 if (!fstype) {
132 error = -ENODEV;
133 goto out;
134 }
135 if (fstype->fs_flags & FS_REQUIRES_DEV)
136
137 need_dev = 1;
138 }
139 if (need_dev) {
140
141 if (kern_path(dev_name, LOOKUP_FOLLOW, &path)) {
142 error = -ENOENT;
143 goto out;
144 }
145 requested_dev_name = tomoyo_realpath_from_path(&path);
146 if (!requested_dev_name) {
147 error = -ENOENT;
148 goto out;
149 }
150 } else {
151
152 if (!dev_name)
153 dev_name = "<NULL>";
154 requested_dev_name = tomoyo_encode(dev_name);
155 if (!requested_dev_name) {
156 error = -ENOMEM;
157 goto out;
158 }
159 }
160 rdev.name = requested_dev_name;
161 tomoyo_fill_path_info(&rdev);
162 r->param_type = TOMOYO_TYPE_MOUNT_ACL;
163 r->param.mount.need_dev = need_dev;
164 r->param.mount.dev = &rdev;
165 r->param.mount.dir = &rdir;
166 r->param.mount.type = &rtype;
167 r->param.mount.flags = flags;
168 do {
169 tomoyo_check_acl(r, tomoyo_check_mount_acl);
170 error = tomoyo_audit_mount_log(r);
171 } while (error == TOMOYO_RETRY_REQUEST);
172 out:
173 kfree(requested_dev_name);
174 kfree(requested_dir_name);
175 if (fstype)
176 put_filesystem(fstype);
177 kfree(requested_type);
178 return error;
179}
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191
192int tomoyo_mount_permission(char *dev_name, struct path *path, char *type,
193 unsigned long flags, void *data_page)
194{
195 struct tomoyo_request_info r;
196 int error;
197 int idx;
198
199 if (tomoyo_init_request_info(&r, NULL, TOMOYO_MAC_FILE_MOUNT)
200 == TOMOYO_CONFIG_DISABLED)
201 return 0;
202 if ((flags & MS_MGC_MSK) == MS_MGC_VAL)
203 flags &= ~MS_MGC_MSK;
204 if (flags & MS_REMOUNT) {
205 type = TOMOYO_MOUNT_REMOUNT_KEYWORD;
206 flags &= ~MS_REMOUNT;
207 }
208 if (flags & MS_MOVE) {
209 type = TOMOYO_MOUNT_MOVE_KEYWORD;
210 flags &= ~MS_MOVE;
211 }
212 if (flags & MS_BIND) {
213 type = TOMOYO_MOUNT_BIND_KEYWORD;
214 flags &= ~MS_BIND;
215 }
216 if (flags & MS_UNBINDABLE) {
217 type = TOMOYO_MOUNT_MAKE_UNBINDABLE_KEYWORD;
218 flags &= ~MS_UNBINDABLE;
219 }
220 if (flags & MS_PRIVATE) {
221 type = TOMOYO_MOUNT_MAKE_PRIVATE_KEYWORD;
222 flags &= ~MS_PRIVATE;
223 }
224 if (flags & MS_SLAVE) {
225 type = TOMOYO_MOUNT_MAKE_SLAVE_KEYWORD;
226 flags &= ~MS_SLAVE;
227 }
228 if (flags & MS_SHARED) {
229 type = TOMOYO_MOUNT_MAKE_SHARED_KEYWORD;
230 flags &= ~MS_SHARED;
231 }
232 if (!type)
233 type = "<NULL>";
234 idx = tomoyo_read_lock();
235 error = tomoyo_mount_acl(&r, dev_name, path, type, flags);
236 tomoyo_read_unlock(idx);
237 return error;
238}
239
240static bool tomoyo_same_mount_acl(const struct tomoyo_acl_info *a,
241 const struct tomoyo_acl_info *b)
242{
243 const struct tomoyo_mount_acl *p1 = container_of(a, typeof(*p1), head);
244 const struct tomoyo_mount_acl *p2 = container_of(b, typeof(*p2), head);
245 return tomoyo_same_acl_head(&p1->head, &p2->head) &&
246 tomoyo_same_name_union(&p1->dev_name, &p2->dev_name) &&
247 tomoyo_same_name_union(&p1->dir_name, &p2->dir_name) &&
248 tomoyo_same_name_union(&p1->fs_type, &p2->fs_type) &&
249 tomoyo_same_number_union(&p1->flags, &p2->flags);
250}
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263int tomoyo_write_mount(char *data, struct tomoyo_domain_info *domain,
264 const bool is_delete)
265{
266 struct tomoyo_mount_acl e = { .head.type = TOMOYO_TYPE_MOUNT_ACL };
267 int error = is_delete ? -ENOENT : -ENOMEM;
268 char *w[4];
269 if (!tomoyo_tokenize(data, w, sizeof(w)) || !w[3][0])
270 return -EINVAL;
271 if (!tomoyo_parse_name_union(w[0], &e.dev_name) ||
272 !tomoyo_parse_name_union(w[1], &e.dir_name) ||
273 !tomoyo_parse_name_union(w[2], &e.fs_type) ||
274 !tomoyo_parse_number_union(w[3], &e.flags))
275 goto out;
276 error = tomoyo_update_domain(&e.head, sizeof(e), is_delete, domain,
277 tomoyo_same_mount_acl, NULL);
278 out:
279 tomoyo_put_name_union(&e.dev_name);
280 tomoyo_put_name_union(&e.dir_name);
281 tomoyo_put_name_union(&e.fs_type);
282 tomoyo_put_number_union(&e.flags);
283 return error;
284}
285