1 // SPDX-License-Identifier: GPL-2.0
2 /* net/atm/resources.c - Statically allocated resources */
3
4 /* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
5
6 /* Fixes
7 * Arnaldo Carvalho de Melo <acme@conectiva.com.br>
8 * 2002/01 - don't free the whole struct sock on sk->destruct time,
9 * use the default destruct function initialized by sock_init_data */
10
11 #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
12
13 #include <linux/ctype.h>
14 #include <linux/string.h>
15 #include <linux/atmdev.h>
16 #include <linux/sonet.h>
17 #include <linux/kernel.h> /* for barrier */
18 #include <linux/module.h>
19 #include <linux/bitops.h>
20 #include <linux/capability.h>
21 #include <linux/delay.h>
22 #include <linux/mutex.h>
23 #include <linux/slab.h>
24
25 #include <net/sock.h> /* for struct sock */
26
27 #include "common.h"
28 #include "resources.h"
29 #include "addr.h"
30
31
32 LIST_HEAD(atm_devs);
33 DEFINE_MUTEX(atm_dev_mutex);
34
__alloc_atm_dev(const char * type)35 static struct atm_dev *__alloc_atm_dev(const char *type)
36 {
37 struct atm_dev *dev;
38
39 dev = kzalloc(sizeof(*dev), GFP_KERNEL);
40 if (!dev)
41 return NULL;
42 dev->type = type;
43 dev->signal = ATM_PHY_SIG_UNKNOWN;
44 dev->link_rate = ATM_OC3_PCR;
45 spin_lock_init(&dev->lock);
46 INIT_LIST_HEAD(&dev->local);
47 INIT_LIST_HEAD(&dev->lecs);
48
49 return dev;
50 }
51
__atm_dev_lookup(int number)52 static struct atm_dev *__atm_dev_lookup(int number)
53 {
54 struct atm_dev *dev;
55 struct list_head *p;
56
57 list_for_each(p, &atm_devs) {
58 dev = list_entry(p, struct atm_dev, dev_list);
59 if (dev->number == number) {
60 atm_dev_hold(dev);
61 return dev;
62 }
63 }
64 return NULL;
65 }
66
atm_dev_lookup(int number)67 struct atm_dev *atm_dev_lookup(int number)
68 {
69 struct atm_dev *dev;
70
71 mutex_lock(&atm_dev_mutex);
72 dev = __atm_dev_lookup(number);
73 mutex_unlock(&atm_dev_mutex);
74 return dev;
75 }
76 EXPORT_SYMBOL(atm_dev_lookup);
77
atm_dev_register(const char * type,struct device * parent,const struct atmdev_ops * ops,int number,unsigned long * flags)78 struct atm_dev *atm_dev_register(const char *type, struct device *parent,
79 const struct atmdev_ops *ops, int number,
80 unsigned long *flags)
81 {
82 struct atm_dev *dev, *inuse;
83
84 dev = __alloc_atm_dev(type);
85 if (!dev) {
86 pr_err("no space for dev %s\n", type);
87 return NULL;
88 }
89 mutex_lock(&atm_dev_mutex);
90 if (number != -1) {
91 inuse = __atm_dev_lookup(number);
92 if (inuse) {
93 atm_dev_put(inuse);
94 mutex_unlock(&atm_dev_mutex);
95 kfree(dev);
96 return NULL;
97 }
98 dev->number = number;
99 } else {
100 dev->number = 0;
101 while ((inuse = __atm_dev_lookup(dev->number))) {
102 atm_dev_put(inuse);
103 dev->number++;
104 }
105 }
106
107 dev->ops = ops;
108 if (flags)
109 dev->flags = *flags;
110 else
111 memset(&dev->flags, 0, sizeof(dev->flags));
112 memset(&dev->stats, 0, sizeof(dev->stats));
113 refcount_set(&dev->refcnt, 1);
114
115 if (atm_proc_dev_register(dev) < 0) {
116 pr_err("atm_proc_dev_register failed for dev %s\n", type);
117 goto out_fail;
118 }
119
120 if (atm_register_sysfs(dev, parent) < 0) {
121 pr_err("atm_register_sysfs failed for dev %s\n", type);
122 atm_proc_dev_deregister(dev);
123 goto out_fail;
124 }
125
126 list_add_tail(&dev->dev_list, &atm_devs);
127
128 out:
129 mutex_unlock(&atm_dev_mutex);
130 return dev;
131
132 out_fail:
133 kfree(dev);
134 dev = NULL;
135 goto out;
136 }
137 EXPORT_SYMBOL(atm_dev_register);
138
atm_dev_deregister(struct atm_dev * dev)139 void atm_dev_deregister(struct atm_dev *dev)
140 {
141 BUG_ON(test_bit(ATM_DF_REMOVED, &dev->flags));
142 set_bit(ATM_DF_REMOVED, &dev->flags);
143
144 /*
145 * if we remove current device from atm_devs list, new device
146 * with same number can appear, such we need deregister proc,
147 * release async all vccs and remove them from vccs list too
148 */
149 mutex_lock(&atm_dev_mutex);
150 list_del(&dev->dev_list);
151 mutex_unlock(&atm_dev_mutex);
152
153 atm_dev_release_vccs(dev);
154 atm_unregister_sysfs(dev);
155 atm_proc_dev_deregister(dev);
156
157 atm_dev_put(dev);
158 }
159 EXPORT_SYMBOL(atm_dev_deregister);
160
copy_aal_stats(struct k_atm_aal_stats * from,struct atm_aal_stats * to)161 static void copy_aal_stats(struct k_atm_aal_stats *from,
162 struct atm_aal_stats *to)
163 {
164 #define __HANDLE_ITEM(i) to->i = atomic_read(&from->i)
165 __AAL_STAT_ITEMS
166 #undef __HANDLE_ITEM
167 }
168
subtract_aal_stats(struct k_atm_aal_stats * from,struct atm_aal_stats * to)169 static void subtract_aal_stats(struct k_atm_aal_stats *from,
170 struct atm_aal_stats *to)
171 {
172 #define __HANDLE_ITEM(i) atomic_sub(to->i, &from->i)
173 __AAL_STAT_ITEMS
174 #undef __HANDLE_ITEM
175 }
176
fetch_stats(struct atm_dev * dev,struct atm_dev_stats __user * arg,int zero)177 static int fetch_stats(struct atm_dev *dev, struct atm_dev_stats __user *arg,
178 int zero)
179 {
180 struct atm_dev_stats tmp;
181 int error = 0;
182
183 copy_aal_stats(&dev->stats.aal0, &tmp.aal0);
184 copy_aal_stats(&dev->stats.aal34, &tmp.aal34);
185 copy_aal_stats(&dev->stats.aal5, &tmp.aal5);
186 if (arg)
187 error = copy_to_user(arg, &tmp, sizeof(tmp));
188 if (zero && !error) {
189 subtract_aal_stats(&dev->stats.aal0, &tmp.aal0);
190 subtract_aal_stats(&dev->stats.aal34, &tmp.aal34);
191 subtract_aal_stats(&dev->stats.aal5, &tmp.aal5);
192 }
193 return error ? -EFAULT : 0;
194 }
195
atm_getnames(void __user * buf,int __user * iobuf_len)196 int atm_getnames(void __user *buf, int __user *iobuf_len)
197 {
198 int error, len, size = 0;
199 struct atm_dev *dev;
200 struct list_head *p;
201 int *tmp_buf, *tmp_p;
202
203 if (get_user(len, iobuf_len))
204 return -EFAULT;
205 mutex_lock(&atm_dev_mutex);
206 list_for_each(p, &atm_devs)
207 size += sizeof(int);
208 if (size > len) {
209 mutex_unlock(&atm_dev_mutex);
210 return -E2BIG;
211 }
212 tmp_buf = kmalloc(size, GFP_ATOMIC);
213 if (!tmp_buf) {
214 mutex_unlock(&atm_dev_mutex);
215 return -ENOMEM;
216 }
217 tmp_p = tmp_buf;
218 list_for_each(p, &atm_devs) {
219 dev = list_entry(p, struct atm_dev, dev_list);
220 *tmp_p++ = dev->number;
221 }
222 mutex_unlock(&atm_dev_mutex);
223 error = ((copy_to_user(buf, tmp_buf, size)) ||
224 put_user(size, iobuf_len))
225 ? -EFAULT : 0;
226 kfree(tmp_buf);
227 return error;
228 }
229
atm_dev_ioctl(unsigned int cmd,void __user * buf,int __user * sioc_len,int number,int compat)230 int atm_dev_ioctl(unsigned int cmd, void __user *buf, int __user *sioc_len,
231 int number, int compat)
232 {
233 int error, len, size = 0;
234 struct atm_dev *dev;
235
236 if (get_user(len, sioc_len))
237 return -EFAULT;
238
239 dev = try_then_request_module(atm_dev_lookup(number), "atm-device-%d",
240 number);
241 if (!dev)
242 return -ENODEV;
243
244 switch (cmd) {
245 case ATM_GETTYPE:
246 size = strlen(dev->type) + 1;
247 if (copy_to_user(buf, dev->type, size)) {
248 error = -EFAULT;
249 goto done;
250 }
251 break;
252 case ATM_GETESI:
253 size = ESI_LEN;
254 if (copy_to_user(buf, dev->esi, size)) {
255 error = -EFAULT;
256 goto done;
257 }
258 break;
259 case ATM_SETESI:
260 {
261 int i;
262
263 for (i = 0; i < ESI_LEN; i++)
264 if (dev->esi[i]) {
265 error = -EEXIST;
266 goto done;
267 }
268 }
269 fallthrough;
270 case ATM_SETESIF:
271 {
272 unsigned char esi[ESI_LEN];
273
274 if (!capable(CAP_NET_ADMIN)) {
275 error = -EPERM;
276 goto done;
277 }
278 if (copy_from_user(esi, buf, ESI_LEN)) {
279 error = -EFAULT;
280 goto done;
281 }
282 memcpy(dev->esi, esi, ESI_LEN);
283 error = ESI_LEN;
284 goto done;
285 }
286 case ATM_GETSTATZ:
287 if (!capable(CAP_NET_ADMIN)) {
288 error = -EPERM;
289 goto done;
290 }
291 fallthrough;
292 case ATM_GETSTAT:
293 size = sizeof(struct atm_dev_stats);
294 error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
295 if (error)
296 goto done;
297 break;
298 case ATM_GETCIRANGE:
299 size = sizeof(struct atm_cirange);
300 if (copy_to_user(buf, &dev->ci_range, size)) {
301 error = -EFAULT;
302 goto done;
303 }
304 break;
305 case ATM_GETLINKRATE:
306 size = sizeof(int);
307 if (copy_to_user(buf, &dev->link_rate, size)) {
308 error = -EFAULT;
309 goto done;
310 }
311 break;
312 case ATM_RSTADDR:
313 if (!capable(CAP_NET_ADMIN)) {
314 error = -EPERM;
315 goto done;
316 }
317 atm_reset_addr(dev, ATM_ADDR_LOCAL);
318 break;
319 case ATM_ADDADDR:
320 case ATM_DELADDR:
321 case ATM_ADDLECSADDR:
322 case ATM_DELLECSADDR:
323 {
324 struct sockaddr_atmsvc addr;
325
326 if (!capable(CAP_NET_ADMIN)) {
327 error = -EPERM;
328 goto done;
329 }
330
331 if (copy_from_user(&addr, buf, sizeof(addr))) {
332 error = -EFAULT;
333 goto done;
334 }
335 if (cmd == ATM_ADDADDR || cmd == ATM_ADDLECSADDR)
336 error = atm_add_addr(dev, &addr,
337 (cmd == ATM_ADDADDR ?
338 ATM_ADDR_LOCAL : ATM_ADDR_LECS));
339 else
340 error = atm_del_addr(dev, &addr,
341 (cmd == ATM_DELADDR ?
342 ATM_ADDR_LOCAL : ATM_ADDR_LECS));
343 goto done;
344 }
345 case ATM_GETADDR:
346 case ATM_GETLECSADDR:
347 error = atm_get_addr(dev, buf, len,
348 (cmd == ATM_GETADDR ?
349 ATM_ADDR_LOCAL : ATM_ADDR_LECS));
350 if (error < 0)
351 goto done;
352 size = error;
353 /* may return 0, but later on size == 0 means "don't
354 write the length" */
355 error = put_user(size, sioc_len) ? -EFAULT : 0;
356 goto done;
357 case ATM_SETLOOP:
358 if (__ATM_LM_XTRMT((int) (unsigned long) buf) &&
359 __ATM_LM_XTLOC((int) (unsigned long) buf) >
360 __ATM_LM_XTRMT((int) (unsigned long) buf)) {
361 error = -EINVAL;
362 goto done;
363 }
364 fallthrough;
365 case ATM_SETCIRANGE:
366 case SONET_GETSTATZ:
367 case SONET_SETDIAG:
368 case SONET_CLRDIAG:
369 case SONET_SETFRAMING:
370 if (!capable(CAP_NET_ADMIN)) {
371 error = -EPERM;
372 goto done;
373 }
374 fallthrough;
375 default:
376 if (IS_ENABLED(CONFIG_COMPAT) && compat) {
377 #ifdef CONFIG_COMPAT
378 if (!dev->ops->compat_ioctl) {
379 error = -EINVAL;
380 goto done;
381 }
382 size = dev->ops->compat_ioctl(dev, cmd, buf);
383 #endif
384 } else {
385 if (!dev->ops->ioctl) {
386 error = -EINVAL;
387 goto done;
388 }
389 size = dev->ops->ioctl(dev, cmd, buf);
390 }
391 if (size < 0) {
392 error = (size == -ENOIOCTLCMD ? -ENOTTY : size);
393 goto done;
394 }
395 }
396
397 if (size)
398 error = put_user(size, sioc_len) ? -EFAULT : 0;
399 else
400 error = 0;
401 done:
402 atm_dev_put(dev);
403 return error;
404 }
405
atm_dev_seq_start(struct seq_file * seq,loff_t * pos)406 void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos)
407 {
408 mutex_lock(&atm_dev_mutex);
409 return seq_list_start_head(&atm_devs, *pos);
410 }
411
atm_dev_seq_stop(struct seq_file * seq,void * v)412 void atm_dev_seq_stop(struct seq_file *seq, void *v)
413 {
414 mutex_unlock(&atm_dev_mutex);
415 }
416
atm_dev_seq_next(struct seq_file * seq,void * v,loff_t * pos)417 void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
418 {
419 return seq_list_next(v, &atm_devs, pos);
420 }
421
