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_dev_ioctl(unsigned int cmd,void __user * arg,int compat)196 int atm_dev_ioctl(unsigned int cmd, void __user *arg, int compat)
197 {
198 void __user *buf;
199 int error, len, number, size = 0;
200 struct atm_dev *dev;
201 struct list_head *p;
202 int *tmp_buf, *tmp_p;
203 int __user *sioc_len;
204 int __user *iobuf_len;
205
206 switch (cmd) {
207 case ATM_GETNAMES:
208 if (IS_ENABLED(CONFIG_COMPAT) && compat) {
209 #ifdef CONFIG_COMPAT
210 struct compat_atm_iobuf __user *ciobuf = arg;
211 compat_uptr_t cbuf;
212 iobuf_len = &ciobuf->length;
213 if (get_user(cbuf, &ciobuf->buffer))
214 return -EFAULT;
215 buf = compat_ptr(cbuf);
216 #endif
217 } else {
218 struct atm_iobuf __user *iobuf = arg;
219 iobuf_len = &iobuf->length;
220 if (get_user(buf, &iobuf->buffer))
221 return -EFAULT;
222 }
223 if (get_user(len, iobuf_len))
224 return -EFAULT;
225 mutex_lock(&atm_dev_mutex);
226 list_for_each(p, &atm_devs)
227 size += sizeof(int);
228 if (size > len) {
229 mutex_unlock(&atm_dev_mutex);
230 return -E2BIG;
231 }
232 tmp_buf = kmalloc(size, GFP_ATOMIC);
233 if (!tmp_buf) {
234 mutex_unlock(&atm_dev_mutex);
235 return -ENOMEM;
236 }
237 tmp_p = tmp_buf;
238 list_for_each(p, &atm_devs) {
239 dev = list_entry(p, struct atm_dev, dev_list);
240 *tmp_p++ = dev->number;
241 }
242 mutex_unlock(&atm_dev_mutex);
243 error = ((copy_to_user(buf, tmp_buf, size)) ||
244 put_user(size, iobuf_len))
245 ? -EFAULT : 0;
246 kfree(tmp_buf);
247 return error;
248 default:
249 break;
250 }
251
252 if (IS_ENABLED(CONFIG_COMPAT) && compat) {
253 #ifdef CONFIG_COMPAT
254 struct compat_atmif_sioc __user *csioc = arg;
255 compat_uptr_t carg;
256
257 sioc_len = &csioc->length;
258 if (get_user(carg, &csioc->arg))
259 return -EFAULT;
260 buf = compat_ptr(carg);
261
262 if (get_user(len, &csioc->length))
263 return -EFAULT;
264 if (get_user(number, &csioc->number))
265 return -EFAULT;
266 #endif
267 } else {
268 struct atmif_sioc __user *sioc = arg;
269
270 sioc_len = &sioc->length;
271 if (get_user(buf, &sioc->arg))
272 return -EFAULT;
273 if (get_user(len, &sioc->length))
274 return -EFAULT;
275 if (get_user(number, &sioc->number))
276 return -EFAULT;
277 }
278
279 dev = try_then_request_module(atm_dev_lookup(number), "atm-device-%d",
280 number);
281 if (!dev)
282 return -ENODEV;
283
284 switch (cmd) {
285 case ATM_GETTYPE:
286 size = strlen(dev->type) + 1;
287 if (copy_to_user(buf, dev->type, size)) {
288 error = -EFAULT;
289 goto done;
290 }
291 break;
292 case ATM_GETESI:
293 size = ESI_LEN;
294 if (copy_to_user(buf, dev->esi, size)) {
295 error = -EFAULT;
296 goto done;
297 }
298 break;
299 case ATM_SETESI:
300 {
301 int i;
302
303 for (i = 0; i < ESI_LEN; i++)
304 if (dev->esi[i]) {
305 error = -EEXIST;
306 goto done;
307 }
308 }
309 /* fall through */
310 case ATM_SETESIF:
311 {
312 unsigned char esi[ESI_LEN];
313
314 if (!capable(CAP_NET_ADMIN)) {
315 error = -EPERM;
316 goto done;
317 }
318 if (copy_from_user(esi, buf, ESI_LEN)) {
319 error = -EFAULT;
320 goto done;
321 }
322 memcpy(dev->esi, esi, ESI_LEN);
323 error = ESI_LEN;
324 goto done;
325 }
326 case ATM_GETSTATZ:
327 if (!capable(CAP_NET_ADMIN)) {
328 error = -EPERM;
329 goto done;
330 }
331 /* fall through */
332 case ATM_GETSTAT:
333 size = sizeof(struct atm_dev_stats);
334 error = fetch_stats(dev, buf, cmd == ATM_GETSTATZ);
335 if (error)
336 goto done;
337 break;
338 case ATM_GETCIRANGE:
339 size = sizeof(struct atm_cirange);
340 if (copy_to_user(buf, &dev->ci_range, size)) {
341 error = -EFAULT;
342 goto done;
343 }
344 break;
345 case ATM_GETLINKRATE:
346 size = sizeof(int);
347 if (copy_to_user(buf, &dev->link_rate, size)) {
348 error = -EFAULT;
349 goto done;
350 }
351 break;
352 case ATM_RSTADDR:
353 if (!capable(CAP_NET_ADMIN)) {
354 error = -EPERM;
355 goto done;
356 }
357 atm_reset_addr(dev, ATM_ADDR_LOCAL);
358 break;
359 case ATM_ADDADDR:
360 case ATM_DELADDR:
361 case ATM_ADDLECSADDR:
362 case ATM_DELLECSADDR:
363 {
364 struct sockaddr_atmsvc addr;
365
366 if (!capable(CAP_NET_ADMIN)) {
367 error = -EPERM;
368 goto done;
369 }
370
371 if (copy_from_user(&addr, buf, sizeof(addr))) {
372 error = -EFAULT;
373 goto done;
374 }
375 if (cmd == ATM_ADDADDR || cmd == ATM_ADDLECSADDR)
376 error = atm_add_addr(dev, &addr,
377 (cmd == ATM_ADDADDR ?
378 ATM_ADDR_LOCAL : ATM_ADDR_LECS));
379 else
380 error = atm_del_addr(dev, &addr,
381 (cmd == ATM_DELADDR ?
382 ATM_ADDR_LOCAL : ATM_ADDR_LECS));
383 goto done;
384 }
385 case ATM_GETADDR:
386 case ATM_GETLECSADDR:
387 error = atm_get_addr(dev, buf, len,
388 (cmd == ATM_GETADDR ?
389 ATM_ADDR_LOCAL : ATM_ADDR_LECS));
390 if (error < 0)
391 goto done;
392 size = error;
393 /* may return 0, but later on size == 0 means "don't
394 write the length" */
395 error = put_user(size, sioc_len) ? -EFAULT : 0;
396 goto done;
397 case ATM_SETLOOP:
398 if (__ATM_LM_XTRMT((int) (unsigned long) buf) &&
399 __ATM_LM_XTLOC((int) (unsigned long) buf) >
400 __ATM_LM_XTRMT((int) (unsigned long) buf)) {
401 error = -EINVAL;
402 goto done;
403 }
404 /* fall through */
405 case ATM_SETCIRANGE:
406 case SONET_GETSTATZ:
407 case SONET_SETDIAG:
408 case SONET_CLRDIAG:
409 case SONET_SETFRAMING:
410 if (!capable(CAP_NET_ADMIN)) {
411 error = -EPERM;
412 goto done;
413 }
414 /* fall through */
415 default:
416 if (IS_ENABLED(CONFIG_COMPAT) && compat) {
417 #ifdef CONFIG_COMPAT
418 if (!dev->ops->compat_ioctl) {
419 error = -EINVAL;
420 goto done;
421 }
422 size = dev->ops->compat_ioctl(dev, cmd, buf);
423 #endif
424 } else {
425 if (!dev->ops->ioctl) {
426 error = -EINVAL;
427 goto done;
428 }
429 size = dev->ops->ioctl(dev, cmd, buf);
430 }
431 if (size < 0) {
432 error = (size == -ENOIOCTLCMD ? -ENOTTY : size);
433 goto done;
434 }
435 }
436
437 if (size)
438 error = put_user(size, sioc_len) ? -EFAULT : 0;
439 else
440 error = 0;
441 done:
442 atm_dev_put(dev);
443 return error;
444 }
445
446 #ifdef CONFIG_PROC_FS
atm_dev_seq_start(struct seq_file * seq,loff_t * pos)447 void *atm_dev_seq_start(struct seq_file *seq, loff_t *pos)
448 {
449 mutex_lock(&atm_dev_mutex);
450 return seq_list_start_head(&atm_devs, *pos);
451 }
452
atm_dev_seq_stop(struct seq_file * seq,void * v)453 void atm_dev_seq_stop(struct seq_file *seq, void *v)
454 {
455 mutex_unlock(&atm_dev_mutex);
456 }
457
atm_dev_seq_next(struct seq_file * seq,void * v,loff_t * pos)458 void *atm_dev_seq_next(struct seq_file *seq, void *v, loff_t *pos)
459 {
460 return seq_list_next(v, &atm_devs, pos);
461 }
462 #endif
463