1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2008, 2009 open80211s Ltd. 4 * Copyright (C) 2019, 2021-2024 Intel Corporation 5 * Author: Luis Carlos Cobo <luisca@cozybit.com> 6 */ 7 #include <linux/gfp.h> 8 #include <linux/kernel.h> 9 #include <linux/random.h> 10 #include <linux/rculist.h> 11 12 #include "ieee80211_i.h" 13 #include "rate.h" 14 #include "mesh.h" 15 16 #define PLINK_CNF_AID(mgmt) ((mgmt)->u.action.u.self_prot.variable + 2) 17 #define PLINK_GET_LLID(p) (p + 2) 18 #define PLINK_GET_PLID(p) (p + 4) 19 20 #define mod_plink_timer(s, t) (mod_timer(&s->mesh->plink_timer, \ 21 jiffies + msecs_to_jiffies(t))) 22 23 enum plink_event { 24 PLINK_UNDEFINED, 25 OPN_ACPT, 26 OPN_RJCT, 27 OPN_IGNR, 28 CNF_ACPT, 29 CNF_RJCT, 30 CNF_IGNR, 31 CLS_ACPT, 32 CLS_IGNR 33 }; 34 35 static const char * const mplstates[] = { 36 [NL80211_PLINK_LISTEN] = "LISTEN", 37 [NL80211_PLINK_OPN_SNT] = "OPN-SNT", 38 [NL80211_PLINK_OPN_RCVD] = "OPN-RCVD", 39 [NL80211_PLINK_CNF_RCVD] = "CNF_RCVD", 40 [NL80211_PLINK_ESTAB] = "ESTAB", 41 [NL80211_PLINK_HOLDING] = "HOLDING", 42 [NL80211_PLINK_BLOCKED] = "BLOCKED" 43 }; 44 45 static const char * const mplevents[] = { 46 [PLINK_UNDEFINED] = "NONE", 47 [OPN_ACPT] = "OPN_ACPT", 48 [OPN_RJCT] = "OPN_RJCT", 49 [OPN_IGNR] = "OPN_IGNR", 50 [CNF_ACPT] = "CNF_ACPT", 51 [CNF_RJCT] = "CNF_RJCT", 52 [CNF_IGNR] = "CNF_IGNR", 53 [CLS_ACPT] = "CLS_ACPT", 54 [CLS_IGNR] = "CLS_IGNR" 55 }; 56 57 /* We only need a valid sta if user configured a minimum rssi_threshold. */ 58 static bool rssi_threshold_check(struct ieee80211_sub_if_data *sdata, 59 struct sta_info *sta) 60 { 61 s32 rssi_threshold = sdata->u.mesh.mshcfg.rssi_threshold; 62 return rssi_threshold == 0 || 63 (sta && 64 (s8)-ewma_signal_read(&sta->deflink.rx_stats_avg.signal) > 65 rssi_threshold); 66 } 67 68 /** 69 * mesh_plink_fsm_restart - restart a mesh peer link finite state machine 70 * 71 * @sta: mesh peer link to restart 72 * 73 * Locking: this function must be called holding sta->mesh->plink_lock 74 */ 75 static inline void mesh_plink_fsm_restart(struct sta_info *sta) 76 { 77 lockdep_assert_held(&sta->mesh->plink_lock); 78 sta->mesh->plink_state = NL80211_PLINK_LISTEN; 79 sta->mesh->llid = sta->mesh->plid = sta->mesh->reason = 0; 80 sta->mesh->plink_retries = 0; 81 } 82 83 /* 84 * mesh_set_short_slot_time - enable / disable ERP short slot time. 85 * 86 * The standard indirectly mandates mesh STAs to turn off short slot time by 87 * disallowing advertising this (802.11-2012 8.4.1.4), but that doesn't mean we 88 * can't be sneaky about it. Enable short slot time if all mesh STAs in the 89 * MBSS support ERP rates. 90 * 91 * Returns BSS_CHANGED_ERP_SLOT or 0 for no change. 92 */ 93 static u64 mesh_set_short_slot_time(struct ieee80211_sub_if_data *sdata) 94 { 95 struct ieee80211_local *local = sdata->local; 96 struct ieee80211_supported_band *sband; 97 struct sta_info *sta; 98 u32 erp_rates = 0; 99 u64 changed = 0; 100 int i; 101 bool short_slot = false; 102 103 sband = ieee80211_get_sband(sdata); 104 if (!sband) 105 return changed; 106 107 if (sband->band == NL80211_BAND_5GHZ) { 108 /* (IEEE 802.11-2012 19.4.5) */ 109 short_slot = true; 110 goto out; 111 } else if (sband->band != NL80211_BAND_2GHZ) { 112 goto out; 113 } 114 115 for (i = 0; i < sband->n_bitrates; i++) 116 if (sband->bitrates[i].flags & IEEE80211_RATE_ERP_G) 117 erp_rates |= BIT(i); 118 119 if (!erp_rates) 120 goto out; 121 122 rcu_read_lock(); 123 list_for_each_entry_rcu(sta, &local->sta_list, list) { 124 if (sdata != sta->sdata || 125 sta->mesh->plink_state != NL80211_PLINK_ESTAB) 126 continue; 127 128 short_slot = false; 129 if (erp_rates & sta->sta.deflink.supp_rates[sband->band]) 130 short_slot = true; 131 else 132 break; 133 } 134 rcu_read_unlock(); 135 136 out: 137 if (sdata->vif.bss_conf.use_short_slot != short_slot) { 138 sdata->vif.bss_conf.use_short_slot = short_slot; 139 changed = BSS_CHANGED_ERP_SLOT; 140 mpl_dbg(sdata, "mesh_plink %pM: ERP short slot time %d\n", 141 sdata->vif.addr, short_slot); 142 } 143 return changed; 144 } 145 146 /** 147 * mesh_set_ht_prot_mode - set correct HT protection mode 148 * @sdata: the (mesh) interface to handle 149 * 150 * Section 9.23.3.5 of IEEE 80211-2012 describes the protection rules for HT 151 * mesh STA in a MBSS. Three HT protection modes are supported for now, non-HT 152 * mixed mode, 20MHz-protection and no-protection mode. non-HT mixed mode is 153 * selected if any non-HT peers are present in our MBSS. 20MHz-protection mode 154 * is selected if all peers in our 20/40MHz MBSS support HT and at least one 155 * HT20 peer is present. Otherwise no-protection mode is selected. 156 * 157 * Returns: BSS_CHANGED_HT or 0 for no change 158 */ 159 static u64 mesh_set_ht_prot_mode(struct ieee80211_sub_if_data *sdata) 160 { 161 struct ieee80211_local *local = sdata->local; 162 struct sta_info *sta; 163 u16 ht_opmode; 164 bool non_ht_sta = false, ht20_sta = false; 165 166 switch (sdata->vif.bss_conf.chanreq.oper.width) { 167 case NL80211_CHAN_WIDTH_20_NOHT: 168 case NL80211_CHAN_WIDTH_5: 169 case NL80211_CHAN_WIDTH_10: 170 return 0; 171 default: 172 break; 173 } 174 175 rcu_read_lock(); 176 list_for_each_entry_rcu(sta, &local->sta_list, list) { 177 if (sdata != sta->sdata || 178 sta->mesh->plink_state != NL80211_PLINK_ESTAB) 179 continue; 180 181 if (sta->sta.deflink.bandwidth > IEEE80211_STA_RX_BW_20) 182 continue; 183 184 if (!sta->sta.deflink.ht_cap.ht_supported) { 185 mpl_dbg(sdata, "nonHT sta (%pM) is present\n", 186 sta->sta.addr); 187 non_ht_sta = true; 188 break; 189 } 190 191 mpl_dbg(sdata, "HT20 sta (%pM) is present\n", sta->sta.addr); 192 ht20_sta = true; 193 } 194 rcu_read_unlock(); 195 196 if (non_ht_sta) 197 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED; 198 else if (ht20_sta && 199 sdata->vif.bss_conf.chanreq.oper.width > NL80211_CHAN_WIDTH_20) 200 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_20MHZ; 201 else 202 ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONE; 203 204 if (sdata->vif.bss_conf.ht_operation_mode == ht_opmode) 205 return 0; 206 207 sdata->vif.bss_conf.ht_operation_mode = ht_opmode; 208 sdata->u.mesh.mshcfg.ht_opmode = ht_opmode; 209 mpl_dbg(sdata, "selected new HT protection mode %d\n", ht_opmode); 210 return BSS_CHANGED_HT; 211 } 212 213 static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata, 214 struct sta_info *sta, 215 enum ieee80211_self_protected_actioncode action, 216 u8 *da, u16 llid, u16 plid, u16 reason) 217 { 218 struct ieee80211_local *local = sdata->local; 219 struct sk_buff *skb; 220 struct ieee80211_tx_info *info; 221 struct ieee80211_mgmt *mgmt; 222 bool include_plid = false; 223 u16 peering_proto = 0; 224 u8 *pos, ie_len = 4; 225 u8 ie_len_he_cap, ie_len_eht_cap; 226 int hdr_len = offsetofend(struct ieee80211_mgmt, u.action.u.self_prot); 227 int err = -ENOMEM; 228 229 ie_len_he_cap = ieee80211_ie_len_he_cap(sdata); 230 ie_len_eht_cap = ieee80211_ie_len_eht_cap(sdata); 231 skb = dev_alloc_skb(local->tx_headroom + 232 hdr_len + 233 2 + /* capability info */ 234 2 + /* AID */ 235 2 + 8 + /* supported rates */ 236 2 + (IEEE80211_MAX_SUPP_RATES - 8) + 237 2 + sdata->u.mesh.mesh_id_len + 238 2 + sizeof(struct ieee80211_meshconf_ie) + 239 2 + sizeof(struct ieee80211_ht_cap) + 240 2 + sizeof(struct ieee80211_ht_operation) + 241 2 + sizeof(struct ieee80211_vht_cap) + 242 2 + sizeof(struct ieee80211_vht_operation) + 243 ie_len_he_cap + 244 2 + 1 + sizeof(struct ieee80211_he_operation) + 245 sizeof(struct ieee80211_he_6ghz_oper) + 246 2 + 1 + sizeof(struct ieee80211_he_6ghz_capa) + 247 ie_len_eht_cap + 248 2 + 1 + offsetof(struct ieee80211_eht_operation, optional) + 249 offsetof(struct ieee80211_eht_operation_info, optional) + 250 2 + 8 + /* peering IE */ 251 sdata->u.mesh.ie_len); 252 if (!skb) 253 return err; 254 info = IEEE80211_SKB_CB(skb); 255 skb_reserve(skb, local->tx_headroom); 256 mgmt = skb_put_zero(skb, hdr_len); 257 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT | 258 IEEE80211_STYPE_ACTION); 259 memcpy(mgmt->da, da, ETH_ALEN); 260 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN); 261 memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN); 262 mgmt->u.action.category = WLAN_CATEGORY_SELF_PROTECTED; 263 mgmt->u.action.u.self_prot.action_code = action; 264 265 if (action != WLAN_SP_MESH_PEERING_CLOSE) { 266 struct ieee80211_supported_band *sband; 267 u32 rate_flags, basic_rates; 268 269 sband = ieee80211_get_sband(sdata); 270 if (!sband) { 271 err = -EINVAL; 272 goto free; 273 } 274 275 /* capability info */ 276 pos = skb_put_zero(skb, 2); 277 if (action == WLAN_SP_MESH_PEERING_CONFIRM) { 278 /* AID */ 279 pos = skb_put(skb, 2); 280 put_unaligned_le16(sta->sta.aid, pos); 281 } 282 283 rate_flags = 284 ieee80211_chandef_rate_flags(&sdata->vif.bss_conf.chanreq.oper); 285 basic_rates = sdata->vif.bss_conf.basic_rates; 286 287 if (ieee80211_put_srates_elem(skb, sband, basic_rates, 288 rate_flags, 0, 289 WLAN_EID_SUPP_RATES) || 290 ieee80211_put_srates_elem(skb, sband, basic_rates, 291 rate_flags, 0, 292 WLAN_EID_EXT_SUPP_RATES) || 293 mesh_add_rsn_ie(sdata, skb) || 294 mesh_add_meshid_ie(sdata, skb) || 295 mesh_add_meshconf_ie(sdata, skb)) 296 goto free; 297 } else { /* WLAN_SP_MESH_PEERING_CLOSE */ 298 info->flags |= IEEE80211_TX_CTL_NO_ACK; 299 if (mesh_add_meshid_ie(sdata, skb)) 300 goto free; 301 } 302 303 /* Add Mesh Peering Management element */ 304 switch (action) { 305 case WLAN_SP_MESH_PEERING_OPEN: 306 break; 307 case WLAN_SP_MESH_PEERING_CONFIRM: 308 ie_len += 2; 309 include_plid = true; 310 break; 311 case WLAN_SP_MESH_PEERING_CLOSE: 312 if (plid) { 313 ie_len += 2; 314 include_plid = true; 315 } 316 ie_len += 2; /* reason code */ 317 break; 318 default: 319 err = -EINVAL; 320 goto free; 321 } 322 323 if (WARN_ON(skb_tailroom(skb) < 2 + ie_len)) 324 goto free; 325 326 pos = skb_put(skb, 2 + ie_len); 327 *pos++ = WLAN_EID_PEER_MGMT; 328 *pos++ = ie_len; 329 memcpy(pos, &peering_proto, 2); 330 pos += 2; 331 put_unaligned_le16(llid, pos); 332 pos += 2; 333 if (include_plid) { 334 put_unaligned_le16(plid, pos); 335 pos += 2; 336 } 337 if (action == WLAN_SP_MESH_PEERING_CLOSE) { 338 put_unaligned_le16(reason, pos); 339 pos += 2; 340 } 341 342 if (action != WLAN_SP_MESH_PEERING_CLOSE) { 343 if (mesh_add_ht_cap_ie(sdata, skb) || 344 mesh_add_ht_oper_ie(sdata, skb) || 345 mesh_add_vht_cap_ie(sdata, skb) || 346 mesh_add_vht_oper_ie(sdata, skb) || 347 mesh_add_he_cap_ie(sdata, skb, ie_len_he_cap) || 348 mesh_add_he_oper_ie(sdata, skb) || 349 mesh_add_he_6ghz_cap_ie(sdata, skb) || 350 mesh_add_eht_cap_ie(sdata, skb, ie_len_eht_cap) || 351 mesh_add_eht_oper_ie(sdata, skb)) 352 goto free; 353 } 354 355 if (mesh_add_vendor_ies(sdata, skb)) 356 goto free; 357 358 ieee80211_tx_skb(sdata, skb); 359 return 0; 360 free: 361 kfree_skb(skb); 362 return err; 363 } 364 365 /** 366 * __mesh_plink_deactivate - deactivate mesh peer link 367 * 368 * @sta: mesh peer link to deactivate 369 * 370 * Mesh paths with this peer as next hop should be flushed 371 * by the caller outside of plink_lock. 372 * 373 * Returns: beacon changed flag if the beacon content changed. 374 * 375 * Locking: the caller must hold sta->mesh->plink_lock 376 */ 377 static u64 __mesh_plink_deactivate(struct sta_info *sta) 378 { 379 struct ieee80211_sub_if_data *sdata = sta->sdata; 380 u64 changed = 0; 381 382 lockdep_assert_held(&sta->mesh->plink_lock); 383 384 if (sta->mesh->plink_state == NL80211_PLINK_ESTAB) 385 changed = mesh_plink_dec_estab_count(sdata); 386 sta->mesh->plink_state = NL80211_PLINK_BLOCKED; 387 388 ieee80211_mps_sta_status_update(sta); 389 changed |= ieee80211_mps_set_sta_local_pm(sta, 390 NL80211_MESH_POWER_UNKNOWN); 391 392 return changed; 393 } 394 395 /** 396 * mesh_plink_deactivate - deactivate mesh peer link 397 * 398 * @sta: mesh peer link to deactivate 399 * 400 * All mesh paths with this peer as next hop will be flushed 401 * 402 * Returns: beacon changed flag if the beacon content changed. 403 */ 404 u64 mesh_plink_deactivate(struct sta_info *sta) 405 { 406 struct ieee80211_sub_if_data *sdata = sta->sdata; 407 u64 changed; 408 409 spin_lock_bh(&sta->mesh->plink_lock); 410 changed = __mesh_plink_deactivate(sta); 411 412 if (!sdata->u.mesh.user_mpm) { 413 sta->mesh->reason = WLAN_REASON_MESH_PEER_CANCELED; 414 mesh_plink_frame_tx(sdata, sta, WLAN_SP_MESH_PEERING_CLOSE, 415 sta->sta.addr, sta->mesh->llid, 416 sta->mesh->plid, sta->mesh->reason); 417 } 418 spin_unlock_bh(&sta->mesh->plink_lock); 419 if (!sdata->u.mesh.user_mpm) 420 del_timer_sync(&sta->mesh->plink_timer); 421 mesh_path_flush_by_nexthop(sta); 422 423 /* make sure no readers can access nexthop sta from here on */ 424 synchronize_net(); 425 426 return changed; 427 } 428 429 static void mesh_sta_info_init(struct ieee80211_sub_if_data *sdata, 430 struct sta_info *sta, 431 struct ieee802_11_elems *elems) 432 { 433 struct ieee80211_local *local = sdata->local; 434 struct ieee80211_supported_band *sband; 435 u32 rates, basic_rates = 0, changed = 0; 436 enum ieee80211_sta_rx_bandwidth bw = sta->sta.deflink.bandwidth; 437 438 sband = ieee80211_get_sband(sdata); 439 if (!sband) 440 return; 441 442 rates = ieee80211_sta_get_rates(sdata, elems, sband->band, 443 &basic_rates); 444 445 spin_lock_bh(&sta->mesh->plink_lock); 446 sta->deflink.rx_stats.last_rx = jiffies; 447 448 /* rates and capabilities don't change during peering */ 449 if (sta->mesh->plink_state == NL80211_PLINK_ESTAB && 450 sta->mesh->processed_beacon) 451 goto out; 452 sta->mesh->processed_beacon = true; 453 454 if (sta->sta.deflink.supp_rates[sband->band] != rates) 455 changed |= IEEE80211_RC_SUPP_RATES_CHANGED; 456 sta->sta.deflink.supp_rates[sband->band] = rates; 457 458 if (ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband, 459 elems->ht_cap_elem, 460 &sta->deflink)) 461 changed |= IEEE80211_RC_BW_CHANGED; 462 463 ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband, 464 elems->vht_cap_elem, NULL, 465 &sta->deflink); 466 467 ieee80211_he_cap_ie_to_sta_he_cap(sdata, sband, elems->he_cap, 468 elems->he_cap_len, 469 elems->he_6ghz_capa, 470 &sta->deflink); 471 472 ieee80211_eht_cap_ie_to_sta_eht_cap(sdata, sband, elems->he_cap, 473 elems->he_cap_len, 474 elems->eht_cap, elems->eht_cap_len, 475 &sta->deflink); 476 477 if (bw != sta->sta.deflink.bandwidth) 478 changed |= IEEE80211_RC_BW_CHANGED; 479 480 /* HT peer is operating 20MHz-only */ 481 if (elems->ht_operation && 482 !(elems->ht_operation->ht_param & 483 IEEE80211_HT_PARAM_CHAN_WIDTH_ANY)) { 484 if (sta->sta.deflink.bandwidth != IEEE80211_STA_RX_BW_20) 485 changed |= IEEE80211_RC_BW_CHANGED; 486 sta->sta.deflink.bandwidth = IEEE80211_STA_RX_BW_20; 487 } 488 489 /* FIXME: this check is wrong without SW rate control */ 490 if (!test_sta_flag(sta, WLAN_STA_RATE_CONTROL)) 491 rate_control_rate_init(&sta->deflink); 492 else 493 rate_control_rate_update(local, sband, &sta->deflink, changed); 494 out: 495 spin_unlock_bh(&sta->mesh->plink_lock); 496 } 497 498 static int mesh_allocate_aid(struct ieee80211_sub_if_data *sdata) 499 { 500 struct sta_info *sta; 501 unsigned long *aid_map; 502 int aid; 503 504 aid_map = bitmap_zalloc(IEEE80211_MAX_AID + 1, GFP_KERNEL); 505 if (!aid_map) 506 return -ENOMEM; 507 508 /* reserve aid 0 for mcast indication */ 509 __set_bit(0, aid_map); 510 511 rcu_read_lock(); 512 list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) 513 __set_bit(sta->sta.aid, aid_map); 514 rcu_read_unlock(); 515 516 aid = find_first_zero_bit(aid_map, IEEE80211_MAX_AID + 1); 517 bitmap_free(aid_map); 518 519 if (aid > IEEE80211_MAX_AID) 520 return -ENOBUFS; 521 522 return aid; 523 } 524 525 static struct sta_info * 526 __mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *hw_addr) 527 { 528 struct sta_info *sta; 529 int aid; 530 531 if (sdata->local->num_sta >= MESH_MAX_PLINKS) 532 return NULL; 533 534 aid = mesh_allocate_aid(sdata); 535 if (aid < 0) 536 return NULL; 537 538 sta = sta_info_alloc(sdata, hw_addr, GFP_KERNEL); 539 if (!sta) 540 return NULL; 541 542 sta->mesh->plink_state = NL80211_PLINK_LISTEN; 543 sta->sta.wme = true; 544 sta->sta.aid = aid; 545 546 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH); 547 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC); 548 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED); 549 550 return sta; 551 } 552 553 static struct sta_info * 554 mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *addr, 555 struct ieee802_11_elems *elems, 556 struct ieee80211_rx_status *rx_status) 557 { 558 struct sta_info *sta = NULL; 559 560 /* Userspace handles station allocation */ 561 if (sdata->u.mesh.user_mpm || 562 sdata->u.mesh.security & IEEE80211_MESH_SEC_AUTHED) { 563 if (mesh_peer_accepts_plinks(elems) && 564 mesh_plink_availables(sdata)) { 565 int sig = 0; 566 567 if (ieee80211_hw_check(&sdata->local->hw, SIGNAL_DBM)) 568 sig = rx_status->signal; 569 570 cfg80211_notify_new_peer_candidate(sdata->dev, addr, 571 elems->ie_start, 572 elems->total_len, 573 sig, GFP_KERNEL); 574 } 575 } else 576 sta = __mesh_sta_info_alloc(sdata, addr); 577 578 return sta; 579 } 580 581 /* 582 * mesh_sta_info_get - return mesh sta info entry for @addr. 583 * 584 * @sdata: local meshif 585 * @addr: peer's address 586 * @elems: IEs from beacon or mesh peering frame. 587 * @rx_status: rx status for the frame for signal reporting 588 * 589 * Return existing or newly allocated sta_info under RCU read lock. 590 * (re)initialize with given IEs. 591 */ 592 static struct sta_info * 593 mesh_sta_info_get(struct ieee80211_sub_if_data *sdata, 594 u8 *addr, struct ieee802_11_elems *elems, 595 struct ieee80211_rx_status *rx_status) __acquires(RCU) 596 { 597 struct sta_info *sta = NULL; 598 599 rcu_read_lock(); 600 sta = sta_info_get(sdata, addr); 601 if (sta) { 602 mesh_sta_info_init(sdata, sta, elems); 603 } else { 604 rcu_read_unlock(); 605 /* can't run atomic */ 606 sta = mesh_sta_info_alloc(sdata, addr, elems, rx_status); 607 if (!sta) { 608 rcu_read_lock(); 609 return NULL; 610 } 611 612 mesh_sta_info_init(sdata, sta, elems); 613 614 if (sta_info_insert_rcu(sta)) 615 return NULL; 616 } 617 618 return sta; 619 } 620 621 /* 622 * mesh_neighbour_update - update or initialize new mesh neighbor. 623 * 624 * @sdata: local meshif 625 * @addr: peer's address 626 * @elems: IEs from beacon or mesh peering frame 627 * @rx_status: rx status for the frame for signal reporting 628 * 629 * Initiates peering if appropriate. 630 */ 631 void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata, 632 u8 *hw_addr, 633 struct ieee802_11_elems *elems, 634 struct ieee80211_rx_status *rx_status) 635 { 636 struct sta_info *sta; 637 u64 changed = 0; 638 639 sta = mesh_sta_info_get(sdata, hw_addr, elems, rx_status); 640 if (!sta) 641 goto out; 642 643 sta->mesh->connected_to_gate = elems->mesh_config->meshconf_form & 644 IEEE80211_MESHCONF_FORM_CONNECTED_TO_GATE; 645 646 if (mesh_peer_accepts_plinks(elems) && 647 sta->mesh->plink_state == NL80211_PLINK_LISTEN && 648 sdata->u.mesh.accepting_plinks && 649 sdata->u.mesh.mshcfg.auto_open_plinks && 650 rssi_threshold_check(sdata, sta)) 651 changed = mesh_plink_open(sta); 652 653 ieee80211_mps_frame_release(sta, elems); 654 out: 655 rcu_read_unlock(); 656 ieee80211_mbss_info_change_notify(sdata, changed); 657 } 658 659 void mesh_plink_timer(struct timer_list *t) 660 { 661 struct mesh_sta *mesh = from_timer(mesh, t, plink_timer); 662 struct sta_info *sta; 663 u16 reason = 0; 664 struct ieee80211_sub_if_data *sdata; 665 struct mesh_config *mshcfg; 666 enum ieee80211_self_protected_actioncode action = 0; 667 668 /* 669 * This STA is valid because sta_info_destroy() will 670 * del_timer_sync() this timer after having made sure 671 * it cannot be re-added (by deleting the plink.) 672 */ 673 sta = mesh->plink_sta; 674 675 if (sta->sdata->local->quiescing) 676 return; 677 678 spin_lock_bh(&sta->mesh->plink_lock); 679 680 /* If a timer fires just before a state transition on another CPU, 681 * we may have already extended the timeout and changed state by the 682 * time we've acquired the lock and arrived here. In that case, 683 * skip this timer and wait for the new one. 684 */ 685 if (time_before(jiffies, sta->mesh->plink_timer.expires)) { 686 mpl_dbg(sta->sdata, 687 "Ignoring timer for %pM in state %s (timer adjusted)", 688 sta->sta.addr, mplstates[sta->mesh->plink_state]); 689 spin_unlock_bh(&sta->mesh->plink_lock); 690 return; 691 } 692 693 /* del_timer() and handler may race when entering these states */ 694 if (sta->mesh->plink_state == NL80211_PLINK_LISTEN || 695 sta->mesh->plink_state == NL80211_PLINK_ESTAB) { 696 mpl_dbg(sta->sdata, 697 "Ignoring timer for %pM in state %s (timer deleted)", 698 sta->sta.addr, mplstates[sta->mesh->plink_state]); 699 spin_unlock_bh(&sta->mesh->plink_lock); 700 return; 701 } 702 703 mpl_dbg(sta->sdata, 704 "Mesh plink timer for %pM fired on state %s\n", 705 sta->sta.addr, mplstates[sta->mesh->plink_state]); 706 sdata = sta->sdata; 707 mshcfg = &sdata->u.mesh.mshcfg; 708 709 switch (sta->mesh->plink_state) { 710 case NL80211_PLINK_OPN_RCVD: 711 case NL80211_PLINK_OPN_SNT: 712 /* retry timer */ 713 if (sta->mesh->plink_retries < mshcfg->dot11MeshMaxRetries) { 714 u32 rand; 715 mpl_dbg(sta->sdata, 716 "Mesh plink for %pM (retry, timeout): %d %d\n", 717 sta->sta.addr, sta->mesh->plink_retries, 718 sta->mesh->plink_timeout); 719 get_random_bytes(&rand, sizeof(u32)); 720 sta->mesh->plink_timeout = sta->mesh->plink_timeout + 721 rand % sta->mesh->plink_timeout; 722 ++sta->mesh->plink_retries; 723 mod_plink_timer(sta, sta->mesh->plink_timeout); 724 action = WLAN_SP_MESH_PEERING_OPEN; 725 break; 726 } 727 reason = WLAN_REASON_MESH_MAX_RETRIES; 728 fallthrough; 729 case NL80211_PLINK_CNF_RCVD: 730 /* confirm timer */ 731 if (!reason) 732 reason = WLAN_REASON_MESH_CONFIRM_TIMEOUT; 733 sta->mesh->plink_state = NL80211_PLINK_HOLDING; 734 mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout); 735 action = WLAN_SP_MESH_PEERING_CLOSE; 736 break; 737 case NL80211_PLINK_HOLDING: 738 /* holding timer */ 739 del_timer(&sta->mesh->plink_timer); 740 mesh_plink_fsm_restart(sta); 741 break; 742 default: 743 break; 744 } 745 spin_unlock_bh(&sta->mesh->plink_lock); 746 if (action) 747 mesh_plink_frame_tx(sdata, sta, action, sta->sta.addr, 748 sta->mesh->llid, sta->mesh->plid, reason); 749 } 750 751 static inline void mesh_plink_timer_set(struct sta_info *sta, u32 timeout) 752 { 753 sta->mesh->plink_timeout = timeout; 754 mod_timer(&sta->mesh->plink_timer, jiffies + msecs_to_jiffies(timeout)); 755 } 756 757 static bool llid_in_use(struct ieee80211_sub_if_data *sdata, 758 u16 llid) 759 { 760 struct ieee80211_local *local = sdata->local; 761 bool in_use = false; 762 struct sta_info *sta; 763 764 rcu_read_lock(); 765 list_for_each_entry_rcu(sta, &local->sta_list, list) { 766 if (sdata != sta->sdata) 767 continue; 768 769 if (!memcmp(&sta->mesh->llid, &llid, sizeof(llid))) { 770 in_use = true; 771 break; 772 } 773 } 774 rcu_read_unlock(); 775 776 return in_use; 777 } 778 779 static u16 mesh_get_new_llid(struct ieee80211_sub_if_data *sdata) 780 { 781 u16 llid; 782 783 do { 784 get_random_bytes(&llid, sizeof(llid)); 785 } while (llid_in_use(sdata, llid)); 786 787 return llid; 788 } 789 790 u64 mesh_plink_open(struct sta_info *sta) 791 { 792 struct ieee80211_sub_if_data *sdata = sta->sdata; 793 u64 changed; 794 795 if (!test_sta_flag(sta, WLAN_STA_AUTH)) 796 return 0; 797 798 spin_lock_bh(&sta->mesh->plink_lock); 799 sta->mesh->llid = mesh_get_new_llid(sdata); 800 if (sta->mesh->plink_state != NL80211_PLINK_LISTEN && 801 sta->mesh->plink_state != NL80211_PLINK_BLOCKED) { 802 spin_unlock_bh(&sta->mesh->plink_lock); 803 return 0; 804 } 805 sta->mesh->plink_state = NL80211_PLINK_OPN_SNT; 806 mesh_plink_timer_set(sta, sdata->u.mesh.mshcfg.dot11MeshRetryTimeout); 807 spin_unlock_bh(&sta->mesh->plink_lock); 808 mpl_dbg(sdata, 809 "Mesh plink: starting establishment with %pM\n", 810 sta->sta.addr); 811 812 /* set the non-peer mode to active during peering */ 813 changed = ieee80211_mps_local_status_update(sdata); 814 815 mesh_plink_frame_tx(sdata, sta, WLAN_SP_MESH_PEERING_OPEN, 816 sta->sta.addr, sta->mesh->llid, 0, 0); 817 return changed; 818 } 819 820 u64 mesh_plink_block(struct sta_info *sta) 821 { 822 u64 changed; 823 824 spin_lock_bh(&sta->mesh->plink_lock); 825 changed = __mesh_plink_deactivate(sta); 826 sta->mesh->plink_state = NL80211_PLINK_BLOCKED; 827 spin_unlock_bh(&sta->mesh->plink_lock); 828 mesh_path_flush_by_nexthop(sta); 829 830 return changed; 831 } 832 833 static void mesh_plink_close(struct ieee80211_sub_if_data *sdata, 834 struct sta_info *sta, 835 enum plink_event event) 836 { 837 struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg; 838 u16 reason = (event == CLS_ACPT) ? 839 WLAN_REASON_MESH_CLOSE : WLAN_REASON_MESH_CONFIG; 840 841 sta->mesh->reason = reason; 842 sta->mesh->plink_state = NL80211_PLINK_HOLDING; 843 mod_plink_timer(sta, mshcfg->dot11MeshHoldingTimeout); 844 } 845 846 static u64 mesh_plink_establish(struct ieee80211_sub_if_data *sdata, 847 struct sta_info *sta) 848 { 849 struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg; 850 u64 changed = 0; 851 852 del_timer(&sta->mesh->plink_timer); 853 sta->mesh->plink_state = NL80211_PLINK_ESTAB; 854 changed |= mesh_plink_inc_estab_count(sdata); 855 changed |= mesh_set_ht_prot_mode(sdata); 856 changed |= mesh_set_short_slot_time(sdata); 857 mpl_dbg(sdata, "Mesh plink with %pM ESTABLISHED\n", sta->sta.addr); 858 ieee80211_mps_sta_status_update(sta); 859 changed |= ieee80211_mps_set_sta_local_pm(sta, mshcfg->power_mode); 860 return changed; 861 } 862 863 /** 864 * mesh_plink_fsm - step @sta MPM based on @event 865 * 866 * @sdata: interface 867 * @sta: mesh neighbor 868 * @event: peering event 869 * 870 * Return: changed MBSS flags 871 */ 872 static u64 mesh_plink_fsm(struct ieee80211_sub_if_data *sdata, 873 struct sta_info *sta, enum plink_event event) 874 { 875 struct mesh_config *mshcfg = &sdata->u.mesh.mshcfg; 876 enum ieee80211_self_protected_actioncode action = 0; 877 u64 changed = 0; 878 bool flush = false; 879 880 mpl_dbg(sdata, "peer %pM in state %s got event %s\n", sta->sta.addr, 881 mplstates[sta->mesh->plink_state], mplevents[event]); 882 883 spin_lock_bh(&sta->mesh->plink_lock); 884 switch (sta->mesh->plink_state) { 885 case NL80211_PLINK_LISTEN: 886 switch (event) { 887 case CLS_ACPT: 888 mesh_plink_fsm_restart(sta); 889 break; 890 case OPN_ACPT: 891 sta->mesh->plink_state = NL80211_PLINK_OPN_RCVD; 892 sta->mesh->llid = mesh_get_new_llid(sdata); 893 mesh_plink_timer_set(sta, 894 mshcfg->dot11MeshRetryTimeout); 895 896 /* set the non-peer mode to active during peering */ 897 changed |= ieee80211_mps_local_status_update(sdata); 898 action = WLAN_SP_MESH_PEERING_OPEN; 899 break; 900 default: 901 break; 902 } 903 break; 904 case NL80211_PLINK_OPN_SNT: 905 switch (event) { 906 case OPN_RJCT: 907 case CNF_RJCT: 908 case CLS_ACPT: 909 mesh_plink_close(sdata, sta, event); 910 action = WLAN_SP_MESH_PEERING_CLOSE; 911 break; 912 case OPN_ACPT: 913 /* retry timer is left untouched */ 914 sta->mesh->plink_state = NL80211_PLINK_OPN_RCVD; 915 action = WLAN_SP_MESH_PEERING_CONFIRM; 916 break; 917 case CNF_ACPT: 918 sta->mesh->plink_state = NL80211_PLINK_CNF_RCVD; 919 mod_plink_timer(sta, mshcfg->dot11MeshConfirmTimeout); 920 break; 921 default: 922 break; 923 } 924 break; 925 case NL80211_PLINK_OPN_RCVD: 926 switch (event) { 927 case OPN_RJCT: 928 case CNF_RJCT: 929 case CLS_ACPT: 930 mesh_plink_close(sdata, sta, event); 931 action = WLAN_SP_MESH_PEERING_CLOSE; 932 break; 933 case OPN_ACPT: 934 action = WLAN_SP_MESH_PEERING_CONFIRM; 935 break; 936 case CNF_ACPT: 937 changed |= mesh_plink_establish(sdata, sta); 938 break; 939 default: 940 break; 941 } 942 break; 943 case NL80211_PLINK_CNF_RCVD: 944 switch (event) { 945 case OPN_RJCT: 946 case CNF_RJCT: 947 case CLS_ACPT: 948 mesh_plink_close(sdata, sta, event); 949 action = WLAN_SP_MESH_PEERING_CLOSE; 950 break; 951 case OPN_ACPT: 952 changed |= mesh_plink_establish(sdata, sta); 953 action = WLAN_SP_MESH_PEERING_CONFIRM; 954 break; 955 default: 956 break; 957 } 958 break; 959 case NL80211_PLINK_ESTAB: 960 switch (event) { 961 case CLS_ACPT: 962 changed |= __mesh_plink_deactivate(sta); 963 changed |= mesh_set_ht_prot_mode(sdata); 964 changed |= mesh_set_short_slot_time(sdata); 965 mesh_plink_close(sdata, sta, event); 966 action = WLAN_SP_MESH_PEERING_CLOSE; 967 flush = true; 968 break; 969 case OPN_ACPT: 970 action = WLAN_SP_MESH_PEERING_CONFIRM; 971 break; 972 default: 973 break; 974 } 975 break; 976 case NL80211_PLINK_HOLDING: 977 switch (event) { 978 case CLS_ACPT: 979 del_timer(&sta->mesh->plink_timer); 980 mesh_plink_fsm_restart(sta); 981 break; 982 case OPN_ACPT: 983 case CNF_ACPT: 984 case OPN_RJCT: 985 case CNF_RJCT: 986 action = WLAN_SP_MESH_PEERING_CLOSE; 987 break; 988 default: 989 break; 990 } 991 break; 992 default: 993 /* should not get here, PLINK_BLOCKED is dealt with at the 994 * beginning of the function 995 */ 996 break; 997 } 998 spin_unlock_bh(&sta->mesh->plink_lock); 999 if (flush) 1000 mesh_path_flush_by_nexthop(sta); 1001 if (action) { 1002 mesh_plink_frame_tx(sdata, sta, action, sta->sta.addr, 1003 sta->mesh->llid, sta->mesh->plid, 1004 sta->mesh->reason); 1005 1006 /* also send confirm in open case */ 1007 if (action == WLAN_SP_MESH_PEERING_OPEN) { 1008 mesh_plink_frame_tx(sdata, sta, 1009 WLAN_SP_MESH_PEERING_CONFIRM, 1010 sta->sta.addr, sta->mesh->llid, 1011 sta->mesh->plid, 0); 1012 } 1013 } 1014 1015 return changed; 1016 } 1017 1018 /* 1019 * mesh_plink_get_event - get correct MPM event 1020 * 1021 * @sdata: interface 1022 * @sta: peer, leave NULL if processing a frame from a new suitable peer 1023 * @elems: peering management IEs 1024 * @ftype: frame type 1025 * @llid: peer's peer link ID 1026 * @plid: peer's local link ID 1027 * 1028 * Return: new peering event for @sta, but PLINK_UNDEFINED should be treated as 1029 * an error. 1030 */ 1031 static enum plink_event 1032 mesh_plink_get_event(struct ieee80211_sub_if_data *sdata, 1033 struct sta_info *sta, 1034 struct ieee802_11_elems *elems, 1035 enum ieee80211_self_protected_actioncode ftype, 1036 u16 llid, u16 plid) 1037 { 1038 enum plink_event event = PLINK_UNDEFINED; 1039 u8 ie_len = elems->peering_len; 1040 bool matches_local; 1041 1042 matches_local = (ftype == WLAN_SP_MESH_PEERING_CLOSE || 1043 mesh_matches_local(sdata, elems)); 1044 1045 /* deny open request from non-matching peer */ 1046 if (!matches_local && !sta) { 1047 event = OPN_RJCT; 1048 goto out; 1049 } 1050 1051 if (!sta) { 1052 if (ftype != WLAN_SP_MESH_PEERING_OPEN) { 1053 mpl_dbg(sdata, "Mesh plink: cls or cnf from unknown peer\n"); 1054 goto out; 1055 } 1056 /* ftype == WLAN_SP_MESH_PEERING_OPEN */ 1057 if (!mesh_plink_free_count(sdata)) { 1058 mpl_dbg(sdata, "Mesh plink error: no more free plinks\n"); 1059 goto out; 1060 } 1061 1062 /* new matching peer */ 1063 event = OPN_ACPT; 1064 goto out; 1065 } else { 1066 if (!test_sta_flag(sta, WLAN_STA_AUTH)) { 1067 mpl_dbg(sdata, "Mesh plink: Action frame from non-authed peer\n"); 1068 goto out; 1069 } 1070 if (sta->mesh->plink_state == NL80211_PLINK_BLOCKED) 1071 goto out; 1072 } 1073 1074 switch (ftype) { 1075 case WLAN_SP_MESH_PEERING_OPEN: 1076 if (!matches_local) 1077 event = OPN_RJCT; 1078 else if (!mesh_plink_free_count(sdata) || 1079 (sta->mesh->plid && sta->mesh->plid != plid)) 1080 event = OPN_IGNR; 1081 else 1082 event = OPN_ACPT; 1083 break; 1084 case WLAN_SP_MESH_PEERING_CONFIRM: 1085 if (!matches_local) 1086 event = CNF_RJCT; 1087 else if (!mesh_plink_free_count(sdata) || 1088 sta->mesh->llid != llid || 1089 (sta->mesh->plid && sta->mesh->plid != plid)) 1090 event = CNF_IGNR; 1091 else 1092 event = CNF_ACPT; 1093 break; 1094 case WLAN_SP_MESH_PEERING_CLOSE: 1095 if (sta->mesh->plink_state == NL80211_PLINK_ESTAB) 1096 /* Do not check for llid or plid. This does not 1097 * follow the standard but since multiple plinks 1098 * per sta are not supported, it is necessary in 1099 * order to avoid a livelock when MP A sees an 1100 * establish peer link to MP B but MP B does not 1101 * see it. This can be caused by a timeout in 1102 * B's peer link establishment or B beign 1103 * restarted. 1104 */ 1105 event = CLS_ACPT; 1106 else if (sta->mesh->plid != plid) 1107 event = CLS_IGNR; 1108 else if (ie_len == 8 && sta->mesh->llid != llid) 1109 event = CLS_IGNR; 1110 else 1111 event = CLS_ACPT; 1112 break; 1113 default: 1114 mpl_dbg(sdata, "Mesh plink: unknown frame subtype\n"); 1115 break; 1116 } 1117 1118 out: 1119 return event; 1120 } 1121 1122 static void 1123 mesh_process_plink_frame(struct ieee80211_sub_if_data *sdata, 1124 struct ieee80211_mgmt *mgmt, 1125 struct ieee802_11_elems *elems, 1126 struct ieee80211_rx_status *rx_status) 1127 { 1128 1129 struct sta_info *sta; 1130 enum plink_event event; 1131 enum ieee80211_self_protected_actioncode ftype; 1132 u64 changed = 0; 1133 u8 ie_len = elems->peering_len; 1134 u16 plid, llid = 0; 1135 1136 if (!elems->peering) { 1137 mpl_dbg(sdata, 1138 "Mesh plink: missing necessary peer link ie\n"); 1139 return; 1140 } 1141 1142 if (elems->rsn_len && 1143 sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) { 1144 mpl_dbg(sdata, 1145 "Mesh plink: can't establish link with secure peer\n"); 1146 return; 1147 } 1148 1149 ftype = mgmt->u.action.u.self_prot.action_code; 1150 if ((ftype == WLAN_SP_MESH_PEERING_OPEN && ie_len != 4) || 1151 (ftype == WLAN_SP_MESH_PEERING_CONFIRM && ie_len != 6) || 1152 (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len != 6 1153 && ie_len != 8)) { 1154 mpl_dbg(sdata, 1155 "Mesh plink: incorrect plink ie length %d %d\n", 1156 ftype, ie_len); 1157 return; 1158 } 1159 1160 if (ftype != WLAN_SP_MESH_PEERING_CLOSE && 1161 (!elems->mesh_id || !elems->mesh_config)) { 1162 mpl_dbg(sdata, "Mesh plink: missing necessary ie\n"); 1163 return; 1164 } 1165 /* Note the lines below are correct, the llid in the frame is the plid 1166 * from the point of view of this host. 1167 */ 1168 plid = get_unaligned_le16(PLINK_GET_LLID(elems->peering)); 1169 if (ftype == WLAN_SP_MESH_PEERING_CONFIRM || 1170 (ftype == WLAN_SP_MESH_PEERING_CLOSE && ie_len == 8)) 1171 llid = get_unaligned_le16(PLINK_GET_PLID(elems->peering)); 1172 1173 /* WARNING: Only for sta pointer, is dropped & re-acquired */ 1174 rcu_read_lock(); 1175 1176 sta = sta_info_get(sdata, mgmt->sa); 1177 1178 if (ftype == WLAN_SP_MESH_PEERING_OPEN && 1179 !rssi_threshold_check(sdata, sta)) { 1180 mpl_dbg(sdata, "Mesh plink: %pM does not meet rssi threshold\n", 1181 mgmt->sa); 1182 goto unlock_rcu; 1183 } 1184 1185 /* Now we will figure out the appropriate event... */ 1186 event = mesh_plink_get_event(sdata, sta, elems, ftype, llid, plid); 1187 1188 if (event == OPN_ACPT) { 1189 rcu_read_unlock(); 1190 /* allocate sta entry if necessary and update info */ 1191 sta = mesh_sta_info_get(sdata, mgmt->sa, elems, rx_status); 1192 if (!sta) { 1193 mpl_dbg(sdata, "Mesh plink: failed to init peer!\n"); 1194 goto unlock_rcu; 1195 } 1196 sta->mesh->plid = plid; 1197 } else if (!sta && event == OPN_RJCT) { 1198 mesh_plink_frame_tx(sdata, NULL, WLAN_SP_MESH_PEERING_CLOSE, 1199 mgmt->sa, 0, plid, 1200 WLAN_REASON_MESH_CONFIG); 1201 goto unlock_rcu; 1202 } else if (!sta || event == PLINK_UNDEFINED) { 1203 /* something went wrong */ 1204 goto unlock_rcu; 1205 } 1206 1207 if (event == CNF_ACPT) { 1208 /* 802.11-2012 13.3.7.2 - update plid on CNF if not set */ 1209 if (!sta->mesh->plid) 1210 sta->mesh->plid = plid; 1211 1212 sta->mesh->aid = get_unaligned_le16(PLINK_CNF_AID(mgmt)); 1213 } 1214 1215 changed |= mesh_plink_fsm(sdata, sta, event); 1216 1217 unlock_rcu: 1218 rcu_read_unlock(); 1219 1220 if (changed) 1221 ieee80211_mbss_info_change_notify(sdata, changed); 1222 } 1223 1224 void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, 1225 struct ieee80211_mgmt *mgmt, size_t len, 1226 struct ieee80211_rx_status *rx_status) 1227 { 1228 struct ieee802_11_elems *elems; 1229 size_t baselen; 1230 u8 *baseaddr; 1231 1232 /* need action_code, aux */ 1233 if (len < IEEE80211_MIN_ACTION_SIZE + 3) 1234 return; 1235 1236 if (sdata->u.mesh.user_mpm) 1237 /* userspace must register for these */ 1238 return; 1239 1240 if (is_multicast_ether_addr(mgmt->da)) { 1241 mpl_dbg(sdata, 1242 "Mesh plink: ignore frame from multicast address\n"); 1243 return; 1244 } 1245 1246 baseaddr = mgmt->u.action.u.self_prot.variable; 1247 baselen = (u8 *) mgmt->u.action.u.self_prot.variable - (u8 *) mgmt; 1248 if (mgmt->u.action.u.self_prot.action_code == 1249 WLAN_SP_MESH_PEERING_CONFIRM) { 1250 baseaddr += 4; 1251 baselen += 4; 1252 1253 if (baselen > len) 1254 return; 1255 } 1256 elems = ieee802_11_parse_elems(baseaddr, len - baselen, true, NULL); 1257 if (elems) { 1258 mesh_process_plink_frame(sdata, mgmt, elems, rx_status); 1259 kfree(elems); 1260 } 1261 } 1262