1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Ioctl handler 4 * Linux ethernet bridge 5 * 6 * Authors: 7 * Lennert Buytenhek <buytenh@gnu.org> 8 */ 9 10 #include <linux/capability.h> 11 #include <linux/kernel.h> 12 #include <linux/if_bridge.h> 13 #include <linux/netdevice.h> 14 #include <linux/slab.h> 15 #include <linux/times.h> 16 #include <net/net_namespace.h> 17 #include <linux/uaccess.h> 18 #include "br_private.h" 19 20 static int get_bridge_ifindices(struct net *net, int *indices, int num) 21 { 22 struct net_device *dev; 23 int i = 0; 24 25 rcu_read_lock(); 26 for_each_netdev_rcu(net, dev) { 27 if (i >= num) 28 break; 29 if (dev->priv_flags & IFF_EBRIDGE) 30 indices[i++] = dev->ifindex; 31 } 32 rcu_read_unlock(); 33 34 return i; 35 } 36 37 /* called with RTNL */ 38 static void get_port_ifindices(struct net_bridge *br, int *ifindices, int num) 39 { 40 struct net_bridge_port *p; 41 42 list_for_each_entry(p, &br->port_list, list) { 43 if (p->port_no < num) 44 ifindices[p->port_no] = p->dev->ifindex; 45 } 46 } 47 48 /* 49 * Format up to a page worth of forwarding table entries 50 * userbuf -- where to copy result 51 * maxnum -- maximum number of entries desired 52 * (limited to a page for sanity) 53 * offset -- number of records to skip 54 */ 55 static int get_fdb_entries(struct net_bridge *br, void __user *userbuf, 56 unsigned long maxnum, unsigned long offset) 57 { 58 int num; 59 void *buf; 60 size_t size; 61 62 /* Clamp size to PAGE_SIZE, test maxnum to avoid overflow */ 63 if (maxnum > PAGE_SIZE/sizeof(struct __fdb_entry)) 64 maxnum = PAGE_SIZE/sizeof(struct __fdb_entry); 65 66 size = maxnum * sizeof(struct __fdb_entry); 67 68 buf = kmalloc(size, GFP_USER); 69 if (!buf) 70 return -ENOMEM; 71 72 num = br_fdb_fillbuf(br, buf, maxnum, offset); 73 if (num > 0) { 74 if (copy_to_user(userbuf, buf, num*sizeof(struct __fdb_entry))) 75 num = -EFAULT; 76 } 77 kfree(buf); 78 79 return num; 80 } 81 82 /* called with RTNL */ 83 static int add_del_if(struct net_bridge *br, int ifindex, int isadd) 84 { 85 struct net *net = dev_net(br->dev); 86 struct net_device *dev; 87 int ret; 88 89 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 90 return -EPERM; 91 92 dev = __dev_get_by_index(net, ifindex); 93 if (dev == NULL) 94 return -EINVAL; 95 96 if (isadd) 97 ret = br_add_if(br, dev, NULL); 98 else 99 ret = br_del_if(br, dev); 100 101 return ret; 102 } 103 104 /* 105 * Legacy ioctl's through SIOCDEVPRIVATE 106 * This interface is deprecated because it was too difficult 107 * to do the translation for 32/64bit ioctl compatibility. 108 */ 109 int br_dev_siocdevprivate(struct net_device *dev, struct ifreq *rq, void __user *data, int cmd) 110 { 111 struct net_bridge *br = netdev_priv(dev); 112 struct net_bridge_port *p = NULL; 113 unsigned long args[4]; 114 void __user *argp; 115 int ret = -EOPNOTSUPP; 116 117 if (in_compat_syscall()) { 118 unsigned int cargs[4]; 119 120 if (copy_from_user(cargs, data, sizeof(cargs))) 121 return -EFAULT; 122 123 args[0] = cargs[0]; 124 args[1] = cargs[1]; 125 args[2] = cargs[2]; 126 args[3] = cargs[3]; 127 128 argp = compat_ptr(args[1]); 129 } else { 130 if (copy_from_user(args, data, sizeof(args))) 131 return -EFAULT; 132 133 argp = (void __user *)args[1]; 134 } 135 136 switch (args[0]) { 137 case BRCTL_ADD_IF: 138 case BRCTL_DEL_IF: 139 return add_del_if(br, args[1], args[0] == BRCTL_ADD_IF); 140 141 case BRCTL_GET_BRIDGE_INFO: 142 { 143 struct __bridge_info b; 144 145 memset(&b, 0, sizeof(struct __bridge_info)); 146 rcu_read_lock(); 147 memcpy(&b.designated_root, &br->designated_root, 8); 148 memcpy(&b.bridge_id, &br->bridge_id, 8); 149 b.root_path_cost = br->root_path_cost; 150 b.max_age = jiffies_to_clock_t(br->max_age); 151 b.hello_time = jiffies_to_clock_t(br->hello_time); 152 b.forward_delay = br->forward_delay; 153 b.bridge_max_age = br->bridge_max_age; 154 b.bridge_hello_time = br->bridge_hello_time; 155 b.bridge_forward_delay = jiffies_to_clock_t(br->bridge_forward_delay); 156 b.topology_change = br->topology_change; 157 b.topology_change_detected = br->topology_change_detected; 158 b.root_port = br->root_port; 159 160 b.stp_enabled = (br->stp_enabled != BR_NO_STP); 161 b.ageing_time = jiffies_to_clock_t(br->ageing_time); 162 b.hello_timer_value = br_timer_value(&br->hello_timer); 163 b.tcn_timer_value = br_timer_value(&br->tcn_timer); 164 b.topology_change_timer_value = br_timer_value(&br->topology_change_timer); 165 b.gc_timer_value = br_timer_value(&br->gc_work.timer); 166 rcu_read_unlock(); 167 168 if (copy_to_user((void __user *)args[1], &b, sizeof(b))) 169 return -EFAULT; 170 171 return 0; 172 } 173 174 case BRCTL_GET_PORT_LIST: 175 { 176 int num, *indices; 177 178 num = args[2]; 179 if (num < 0) 180 return -EINVAL; 181 if (num == 0) 182 num = 256; 183 if (num > BR_MAX_PORTS) 184 num = BR_MAX_PORTS; 185 186 indices = kcalloc(num, sizeof(int), GFP_KERNEL); 187 if (indices == NULL) 188 return -ENOMEM; 189 190 get_port_ifindices(br, indices, num); 191 if (copy_to_user(argp, indices, num * sizeof(int))) 192 num = -EFAULT; 193 kfree(indices); 194 return num; 195 } 196 197 case BRCTL_SET_BRIDGE_FORWARD_DELAY: 198 if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN)) 199 return -EPERM; 200 201 ret = br_set_forward_delay(br, args[1]); 202 break; 203 204 case BRCTL_SET_BRIDGE_HELLO_TIME: 205 if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN)) 206 return -EPERM; 207 208 ret = br_set_hello_time(br, args[1]); 209 break; 210 211 case BRCTL_SET_BRIDGE_MAX_AGE: 212 if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN)) 213 return -EPERM; 214 215 ret = br_set_max_age(br, args[1]); 216 break; 217 218 case BRCTL_SET_AGEING_TIME: 219 if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN)) 220 return -EPERM; 221 222 ret = br_set_ageing_time(br, args[1]); 223 break; 224 225 case BRCTL_GET_PORT_INFO: 226 { 227 struct __port_info p; 228 struct net_bridge_port *pt; 229 230 rcu_read_lock(); 231 if ((pt = br_get_port(br, args[2])) == NULL) { 232 rcu_read_unlock(); 233 return -EINVAL; 234 } 235 236 memset(&p, 0, sizeof(struct __port_info)); 237 memcpy(&p.designated_root, &pt->designated_root, 8); 238 memcpy(&p.designated_bridge, &pt->designated_bridge, 8); 239 p.port_id = pt->port_id; 240 p.designated_port = pt->designated_port; 241 p.path_cost = pt->path_cost; 242 p.designated_cost = pt->designated_cost; 243 p.state = pt->state; 244 p.top_change_ack = pt->topology_change_ack; 245 p.config_pending = pt->config_pending; 246 p.message_age_timer_value = br_timer_value(&pt->message_age_timer); 247 p.forward_delay_timer_value = br_timer_value(&pt->forward_delay_timer); 248 p.hold_timer_value = br_timer_value(&pt->hold_timer); 249 250 rcu_read_unlock(); 251 252 if (copy_to_user(argp, &p, sizeof(p))) 253 return -EFAULT; 254 255 return 0; 256 } 257 258 case BRCTL_SET_BRIDGE_STP_STATE: 259 if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN)) 260 return -EPERM; 261 262 ret = br_stp_set_enabled(br, args[1], NULL); 263 break; 264 265 case BRCTL_SET_BRIDGE_PRIORITY: 266 if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN)) 267 return -EPERM; 268 269 br_stp_set_bridge_priority(br, args[1]); 270 ret = 0; 271 break; 272 273 case BRCTL_SET_PORT_PRIORITY: 274 { 275 if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN)) 276 return -EPERM; 277 278 spin_lock_bh(&br->lock); 279 if ((p = br_get_port(br, args[1])) == NULL) 280 ret = -EINVAL; 281 else 282 ret = br_stp_set_port_priority(p, args[2]); 283 spin_unlock_bh(&br->lock); 284 break; 285 } 286 287 case BRCTL_SET_PATH_COST: 288 { 289 if (!ns_capable(dev_net(dev)->user_ns, CAP_NET_ADMIN)) 290 return -EPERM; 291 292 spin_lock_bh(&br->lock); 293 if ((p = br_get_port(br, args[1])) == NULL) 294 ret = -EINVAL; 295 else 296 ret = br_stp_set_path_cost(p, args[2]); 297 spin_unlock_bh(&br->lock); 298 break; 299 } 300 301 case BRCTL_GET_FDB_ENTRIES: 302 return get_fdb_entries(br, argp, args[2], args[3]); 303 } 304 305 if (!ret) { 306 if (p) 307 br_ifinfo_notify(RTM_NEWLINK, NULL, p); 308 else 309 netdev_state_change(br->dev); 310 } 311 312 return ret; 313 } 314 315 static int old_deviceless(struct net *net, void __user *uarg) 316 { 317 unsigned long args[3]; 318 319 if (copy_from_user(args, uarg, sizeof(args))) 320 return -EFAULT; 321 322 switch (args[0]) { 323 case BRCTL_GET_VERSION: 324 return BRCTL_VERSION; 325 326 case BRCTL_GET_BRIDGES: 327 { 328 int *indices; 329 int ret = 0; 330 331 if (args[2] >= 2048) 332 return -ENOMEM; 333 indices = kcalloc(args[2], sizeof(int), GFP_KERNEL); 334 if (indices == NULL) 335 return -ENOMEM; 336 337 args[2] = get_bridge_ifindices(net, indices, args[2]); 338 339 ret = copy_to_user(uarg, indices, args[2]*sizeof(int)) 340 ? -EFAULT : args[2]; 341 342 kfree(indices); 343 return ret; 344 } 345 346 case BRCTL_ADD_BRIDGE: 347 case BRCTL_DEL_BRIDGE: 348 { 349 char buf[IFNAMSIZ]; 350 351 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) 352 return -EPERM; 353 354 if (copy_from_user(buf, (void __user *)args[1], IFNAMSIZ)) 355 return -EFAULT; 356 357 buf[IFNAMSIZ-1] = 0; 358 359 if (args[0] == BRCTL_ADD_BRIDGE) 360 return br_add_bridge(net, buf); 361 362 return br_del_bridge(net, buf); 363 } 364 } 365 366 return -EOPNOTSUPP; 367 } 368 369 int br_ioctl_stub(struct net *net, struct net_bridge *br, unsigned int cmd, 370 struct ifreq *ifr, void __user *uarg) 371 { 372 int ret = -EOPNOTSUPP; 373 374 rtnl_lock(); 375 376 switch (cmd) { 377 case SIOCGIFBR: 378 case SIOCSIFBR: 379 ret = old_deviceless(net, uarg); 380 break; 381 case SIOCBRADDBR: 382 case SIOCBRDELBR: 383 { 384 char buf[IFNAMSIZ]; 385 386 if (!ns_capable(net->user_ns, CAP_NET_ADMIN)) { 387 ret = -EPERM; 388 break; 389 } 390 391 if (copy_from_user(buf, uarg, IFNAMSIZ)) { 392 ret = -EFAULT; 393 break; 394 } 395 396 buf[IFNAMSIZ-1] = 0; 397 if (cmd == SIOCBRADDBR) 398 ret = br_add_bridge(net, buf); 399 else 400 ret = br_del_bridge(net, buf); 401 } 402 break; 403 case SIOCBRADDIF: 404 case SIOCBRDELIF: 405 ret = add_del_if(br, ifr->ifr_ifindex, cmd == SIOCBRADDIF); 406 break; 407 } 408 409 rtnl_unlock(); 410 411 return ret; 412 } 413