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