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 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 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 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 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); 136 137 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); 157 158 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 } 165 166 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 } 173 174 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 } 192 193 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 } 225 226 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 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 } 408 409 void atm_dev_seq_stop(struct seq_file *seq, void *v) 410 { 411 mutex_unlock(&atm_dev_mutex); 412 } 413 414 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