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TOMOYO Linux Cross Reference
Linux/net/batman-adv/routing.c

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  1 // SPDX-License-Identifier: GPL-2.0
  2 /* Copyright (C) 2007-2019  B.A.T.M.A.N. contributors:
  3  *
  4  * Marek Lindner, Simon Wunderlich
  5  */
  6 
  7 #include "routing.h"
  8 #include "main.h"
  9 
 10 #include <linux/atomic.h>
 11 #include <linux/byteorder/generic.h>
 12 #include <linux/compiler.h>
 13 #include <linux/errno.h>
 14 #include <linux/etherdevice.h>
 15 #include <linux/if_ether.h>
 16 #include <linux/jiffies.h>
 17 #include <linux/kref.h>
 18 #include <linux/netdevice.h>
 19 #include <linux/printk.h>
 20 #include <linux/rculist.h>
 21 #include <linux/rcupdate.h>
 22 #include <linux/skbuff.h>
 23 #include <linux/spinlock.h>
 24 #include <linux/stddef.h>
 25 #include <uapi/linux/batadv_packet.h>
 26 
 27 #include "bitarray.h"
 28 #include "bridge_loop_avoidance.h"
 29 #include "distributed-arp-table.h"
 30 #include "fragmentation.h"
 31 #include "hard-interface.h"
 32 #include "icmp_socket.h"
 33 #include "log.h"
 34 #include "network-coding.h"
 35 #include "originator.h"
 36 #include "send.h"
 37 #include "soft-interface.h"
 38 #include "tp_meter.h"
 39 #include "translation-table.h"
 40 #include "tvlv.h"
 41 
 42 static int batadv_route_unicast_packet(struct sk_buff *skb,
 43                                        struct batadv_hard_iface *recv_if);
 44 
 45 /**
 46  * _batadv_update_route() - set the router for this originator
 47  * @bat_priv: the bat priv with all the soft interface information
 48  * @orig_node: orig node which is to be configured
 49  * @recv_if: the receive interface for which this route is set
 50  * @neigh_node: neighbor which should be the next router
 51  *
 52  * This function does not perform any error checks
 53  */
 54 static void _batadv_update_route(struct batadv_priv *bat_priv,
 55                                  struct batadv_orig_node *orig_node,
 56                                  struct batadv_hard_iface *recv_if,
 57                                  struct batadv_neigh_node *neigh_node)
 58 {
 59         struct batadv_orig_ifinfo *orig_ifinfo;
 60         struct batadv_neigh_node *curr_router;
 61 
 62         orig_ifinfo = batadv_orig_ifinfo_get(orig_node, recv_if);
 63         if (!orig_ifinfo)
 64                 return;
 65 
 66         spin_lock_bh(&orig_node->neigh_list_lock);
 67         /* curr_router used earlier may not be the current orig_ifinfo->router
 68          * anymore because it was dereferenced outside of the neigh_list_lock
 69          * protected region. After the new best neighbor has replace the current
 70          * best neighbor the reference counter needs to decrease. Consequently,
 71          * the code needs to ensure the curr_router variable contains a pointer
 72          * to the replaced best neighbor.
 73          */
 74         curr_router = rcu_dereference_protected(orig_ifinfo->router, true);
 75 
 76         /* increase refcount of new best neighbor */
 77         if (neigh_node)
 78                 kref_get(&neigh_node->refcount);
 79 
 80         rcu_assign_pointer(orig_ifinfo->router, neigh_node);
 81         spin_unlock_bh(&orig_node->neigh_list_lock);
 82         batadv_orig_ifinfo_put(orig_ifinfo);
 83 
 84         /* route deleted */
 85         if (curr_router && !neigh_node) {
 86                 batadv_dbg(BATADV_DBG_ROUTES, bat_priv,
 87                            "Deleting route towards: %pM\n", orig_node->orig);
 88                 batadv_tt_global_del_orig(bat_priv, orig_node, -1,
 89                                           "Deleted route towards originator");
 90 
 91         /* route added */
 92         } else if (!curr_router && neigh_node) {
 93                 batadv_dbg(BATADV_DBG_ROUTES, bat_priv,
 94                            "Adding route towards: %pM (via %pM)\n",
 95                            orig_node->orig, neigh_node->addr);
 96         /* route changed */
 97         } else if (neigh_node && curr_router) {
 98                 batadv_dbg(BATADV_DBG_ROUTES, bat_priv,
 99                            "Changing route towards: %pM (now via %pM - was via %pM)\n",
100                            orig_node->orig, neigh_node->addr,
101                            curr_router->addr);
102         }
103 
104         /* decrease refcount of previous best neighbor */
105         if (curr_router)
106                 batadv_neigh_node_put(curr_router);
107 }
108 
109 /**
110  * batadv_update_route() - set the router for this originator
111  * @bat_priv: the bat priv with all the soft interface information
112  * @orig_node: orig node which is to be configured
113  * @recv_if: the receive interface for which this route is set
114  * @neigh_node: neighbor which should be the next router
115  */
116 void batadv_update_route(struct batadv_priv *bat_priv,
117                          struct batadv_orig_node *orig_node,
118                          struct batadv_hard_iface *recv_if,
119                          struct batadv_neigh_node *neigh_node)
120 {
121         struct batadv_neigh_node *router = NULL;
122 
123         if (!orig_node)
124                 goto out;
125 
126         router = batadv_orig_router_get(orig_node, recv_if);
127 
128         if (router != neigh_node)
129                 _batadv_update_route(bat_priv, orig_node, recv_if, neigh_node);
130 
131 out:
132         if (router)
133                 batadv_neigh_node_put(router);
134 }
135 
136 /**
137  * batadv_window_protected() - checks whether the host restarted and is in the
138  *  protection time.
139  * @bat_priv: the bat priv with all the soft interface information
140  * @seq_num_diff: difference between the current/received sequence number and
141  *  the last sequence number
142  * @seq_old_max_diff: maximum age of sequence number not considered as restart
143  * @last_reset: jiffies timestamp of the last reset, will be updated when reset
144  *  is detected
145  * @protection_started: is set to true if the protection window was started,
146  *   doesn't change otherwise.
147  *
148  * Return:
149  *  false if the packet is to be accepted.
150  *  true if the packet is to be ignored.
151  */
152 bool batadv_window_protected(struct batadv_priv *bat_priv, s32 seq_num_diff,
153                              s32 seq_old_max_diff, unsigned long *last_reset,
154                              bool *protection_started)
155 {
156         if (seq_num_diff <= -seq_old_max_diff ||
157             seq_num_diff >= BATADV_EXPECTED_SEQNO_RANGE) {
158                 if (!batadv_has_timed_out(*last_reset,
159                                           BATADV_RESET_PROTECTION_MS))
160                         return true;
161 
162                 *last_reset = jiffies;
163                 if (protection_started)
164                         *protection_started = true;
165                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
166                            "old packet received, start protection\n");
167         }
168 
169         return false;
170 }
171 
172 /**
173  * batadv_check_management_packet() - Check preconditions for management packets
174  * @skb: incoming packet buffer
175  * @hard_iface: incoming hard interface
176  * @header_len: minimal header length of packet type
177  *
178  * Return: true when management preconditions are met, false otherwise
179  */
180 bool batadv_check_management_packet(struct sk_buff *skb,
181                                     struct batadv_hard_iface *hard_iface,
182                                     int header_len)
183 {
184         struct ethhdr *ethhdr;
185 
186         /* drop packet if it has not necessary minimum size */
187         if (unlikely(!pskb_may_pull(skb, header_len)))
188                 return false;
189 
190         ethhdr = eth_hdr(skb);
191 
192         /* packet with broadcast indication but unicast recipient */
193         if (!is_broadcast_ether_addr(ethhdr->h_dest))
194                 return false;
195 
196         /* packet with invalid sender address */
197         if (!is_valid_ether_addr(ethhdr->h_source))
198                 return false;
199 
200         /* create a copy of the skb, if needed, to modify it. */
201         if (skb_cow(skb, 0) < 0)
202                 return false;
203 
204         /* keep skb linear */
205         if (skb_linearize(skb) < 0)
206                 return false;
207 
208         return true;
209 }
210 
211 /**
212  * batadv_recv_my_icmp_packet() - receive an icmp packet locally
213  * @bat_priv: the bat priv with all the soft interface information
214  * @skb: icmp packet to process
215  *
216  * Return: NET_RX_SUCCESS if the packet has been consumed or NET_RX_DROP
217  * otherwise.
218  */
219 static int batadv_recv_my_icmp_packet(struct batadv_priv *bat_priv,
220                                       struct sk_buff *skb)
221 {
222         struct batadv_hard_iface *primary_if = NULL;
223         struct batadv_orig_node *orig_node = NULL;
224         struct batadv_icmp_header *icmph;
225         int res, ret = NET_RX_DROP;
226 
227         icmph = (struct batadv_icmp_header *)skb->data;
228 
229         switch (icmph->msg_type) {
230         case BATADV_ECHO_REPLY:
231         case BATADV_DESTINATION_UNREACHABLE:
232         case BATADV_TTL_EXCEEDED:
233                 /* receive the packet */
234                 if (skb_linearize(skb) < 0)
235                         break;
236 
237                 batadv_socket_receive_packet(icmph, skb->len);
238                 break;
239         case BATADV_ECHO_REQUEST:
240                 /* answer echo request (ping) */
241                 primary_if = batadv_primary_if_get_selected(bat_priv);
242                 if (!primary_if)
243                         goto out;
244 
245                 /* get routing information */
246                 orig_node = batadv_orig_hash_find(bat_priv, icmph->orig);
247                 if (!orig_node)
248                         goto out;
249 
250                 /* create a copy of the skb, if needed, to modify it. */
251                 if (skb_cow(skb, ETH_HLEN) < 0)
252                         goto out;
253 
254                 icmph = (struct batadv_icmp_header *)skb->data;
255 
256                 ether_addr_copy(icmph->dst, icmph->orig);
257                 ether_addr_copy(icmph->orig, primary_if->net_dev->dev_addr);
258                 icmph->msg_type = BATADV_ECHO_REPLY;
259                 icmph->ttl = BATADV_TTL;
260 
261                 res = batadv_send_skb_to_orig(skb, orig_node, NULL);
262                 if (res == NET_XMIT_SUCCESS)
263                         ret = NET_RX_SUCCESS;
264 
265                 /* skb was consumed */
266                 skb = NULL;
267                 break;
268         case BATADV_TP:
269                 if (!pskb_may_pull(skb, sizeof(struct batadv_icmp_tp_packet)))
270                         goto out;
271 
272                 batadv_tp_meter_recv(bat_priv, skb);
273                 ret = NET_RX_SUCCESS;
274                 /* skb was consumed */
275                 skb = NULL;
276                 goto out;
277         default:
278                 /* drop unknown type */
279                 goto out;
280         }
281 out:
282         if (primary_if)
283                 batadv_hardif_put(primary_if);
284         if (orig_node)
285                 batadv_orig_node_put(orig_node);
286 
287         kfree_skb(skb);
288 
289         return ret;
290 }
291 
292 static int batadv_recv_icmp_ttl_exceeded(struct batadv_priv *bat_priv,
293                                          struct sk_buff *skb)
294 {
295         struct batadv_hard_iface *primary_if = NULL;
296         struct batadv_orig_node *orig_node = NULL;
297         struct batadv_icmp_packet *icmp_packet;
298         int res, ret = NET_RX_DROP;
299 
300         icmp_packet = (struct batadv_icmp_packet *)skb->data;
301 
302         /* send TTL exceeded if packet is an echo request (traceroute) */
303         if (icmp_packet->msg_type != BATADV_ECHO_REQUEST) {
304                 pr_debug("Warning - can't forward icmp packet from %pM to %pM: ttl exceeded\n",
305                          icmp_packet->orig, icmp_packet->dst);
306                 goto out;
307         }
308 
309         primary_if = batadv_primary_if_get_selected(bat_priv);
310         if (!primary_if)
311                 goto out;
312 
313         /* get routing information */
314         orig_node = batadv_orig_hash_find(bat_priv, icmp_packet->orig);
315         if (!orig_node)
316                 goto out;
317 
318         /* create a copy of the skb, if needed, to modify it. */
319         if (skb_cow(skb, ETH_HLEN) < 0)
320                 goto out;
321 
322         icmp_packet = (struct batadv_icmp_packet *)skb->data;
323 
324         ether_addr_copy(icmp_packet->dst, icmp_packet->orig);
325         ether_addr_copy(icmp_packet->orig, primary_if->net_dev->dev_addr);
326         icmp_packet->msg_type = BATADV_TTL_EXCEEDED;
327         icmp_packet->ttl = BATADV_TTL;
328 
329         res = batadv_send_skb_to_orig(skb, orig_node, NULL);
330         if (res == NET_RX_SUCCESS)
331                 ret = NET_XMIT_SUCCESS;
332 
333         /* skb was consumed */
334         skb = NULL;
335 
336 out:
337         if (primary_if)
338                 batadv_hardif_put(primary_if);
339         if (orig_node)
340                 batadv_orig_node_put(orig_node);
341 
342         kfree_skb(skb);
343 
344         return ret;
345 }
346 
347 /**
348  * batadv_recv_icmp_packet() - Process incoming icmp packet
349  * @skb: incoming packet buffer
350  * @recv_if: incoming hard interface
351  *
352  * Return: NET_RX_SUCCESS on success or NET_RX_DROP in case of failure
353  */
354 int batadv_recv_icmp_packet(struct sk_buff *skb,
355                             struct batadv_hard_iface *recv_if)
356 {
357         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
358         struct batadv_icmp_header *icmph;
359         struct batadv_icmp_packet_rr *icmp_packet_rr;
360         struct ethhdr *ethhdr;
361         struct batadv_orig_node *orig_node = NULL;
362         int hdr_size = sizeof(struct batadv_icmp_header);
363         int res, ret = NET_RX_DROP;
364 
365         /* drop packet if it has not necessary minimum size */
366         if (unlikely(!pskb_may_pull(skb, hdr_size)))
367                 goto free_skb;
368 
369         ethhdr = eth_hdr(skb);
370 
371         /* packet with unicast indication but non-unicast recipient */
372         if (!is_valid_ether_addr(ethhdr->h_dest))
373                 goto free_skb;
374 
375         /* packet with broadcast/multicast sender address */
376         if (is_multicast_ether_addr(ethhdr->h_source))
377                 goto free_skb;
378 
379         /* not for me */
380         if (!batadv_is_my_mac(bat_priv, ethhdr->h_dest))
381                 goto free_skb;
382 
383         icmph = (struct batadv_icmp_header *)skb->data;
384 
385         /* add record route information if not full */
386         if ((icmph->msg_type == BATADV_ECHO_REPLY ||
387              icmph->msg_type == BATADV_ECHO_REQUEST) &&
388             skb->len >= sizeof(struct batadv_icmp_packet_rr)) {
389                 if (skb_linearize(skb) < 0)
390                         goto free_skb;
391 
392                 /* create a copy of the skb, if needed, to modify it. */
393                 if (skb_cow(skb, ETH_HLEN) < 0)
394                         goto free_skb;
395 
396                 ethhdr = eth_hdr(skb);
397                 icmph = (struct batadv_icmp_header *)skb->data;
398                 icmp_packet_rr = (struct batadv_icmp_packet_rr *)icmph;
399                 if (icmp_packet_rr->rr_cur >= BATADV_RR_LEN)
400                         goto free_skb;
401 
402                 ether_addr_copy(icmp_packet_rr->rr[icmp_packet_rr->rr_cur],
403                                 ethhdr->h_dest);
404                 icmp_packet_rr->rr_cur++;
405         }
406 
407         /* packet for me */
408         if (batadv_is_my_mac(bat_priv, icmph->dst))
409                 return batadv_recv_my_icmp_packet(bat_priv, skb);
410 
411         /* TTL exceeded */
412         if (icmph->ttl < 2)
413                 return batadv_recv_icmp_ttl_exceeded(bat_priv, skb);
414 
415         /* get routing information */
416         orig_node = batadv_orig_hash_find(bat_priv, icmph->dst);
417         if (!orig_node)
418                 goto free_skb;
419 
420         /* create a copy of the skb, if needed, to modify it. */
421         if (skb_cow(skb, ETH_HLEN) < 0)
422                 goto put_orig_node;
423 
424         icmph = (struct batadv_icmp_header *)skb->data;
425 
426         /* decrement ttl */
427         icmph->ttl--;
428 
429         /* route it */
430         res = batadv_send_skb_to_orig(skb, orig_node, recv_if);
431         if (res == NET_XMIT_SUCCESS)
432                 ret = NET_RX_SUCCESS;
433 
434         /* skb was consumed */
435         skb = NULL;
436 
437 put_orig_node:
438         if (orig_node)
439                 batadv_orig_node_put(orig_node);
440 free_skb:
441         kfree_skb(skb);
442 
443         return ret;
444 }
445 
446 /**
447  * batadv_check_unicast_packet() - Check for malformed unicast packets
448  * @bat_priv: the bat priv with all the soft interface information
449  * @skb: packet to check
450  * @hdr_size: size of header to pull
451  *
452  * Check for short header and bad addresses in given packet.
453  *
454  * Return: negative value when check fails and 0 otherwise. The negative value
455  * depends on the reason: -ENODATA for bad header, -EBADR for broadcast
456  * destination or source, and -EREMOTE for non-local (other host) destination.
457  */
458 static int batadv_check_unicast_packet(struct batadv_priv *bat_priv,
459                                        struct sk_buff *skb, int hdr_size)
460 {
461         struct ethhdr *ethhdr;
462 
463         /* drop packet if it has not necessary minimum size */
464         if (unlikely(!pskb_may_pull(skb, hdr_size)))
465                 return -ENODATA;
466 
467         ethhdr = eth_hdr(skb);
468 
469         /* packet with unicast indication but non-unicast recipient */
470         if (!is_valid_ether_addr(ethhdr->h_dest))
471                 return -EBADR;
472 
473         /* packet with broadcast/multicast sender address */
474         if (is_multicast_ether_addr(ethhdr->h_source))
475                 return -EBADR;
476 
477         /* not for me */
478         if (!batadv_is_my_mac(bat_priv, ethhdr->h_dest))
479                 return -EREMOTE;
480 
481         return 0;
482 }
483 
484 /**
485  * batadv_last_bonding_get() - Get last_bonding_candidate of orig_node
486  * @orig_node: originator node whose last bonding candidate should be retrieved
487  *
488  * Return: last bonding candidate of router or NULL if not found
489  *
490  * The object is returned with refcounter increased by 1.
491  */
492 static struct batadv_orig_ifinfo *
493 batadv_last_bonding_get(struct batadv_orig_node *orig_node)
494 {
495         struct batadv_orig_ifinfo *last_bonding_candidate;
496 
497         spin_lock_bh(&orig_node->neigh_list_lock);
498         last_bonding_candidate = orig_node->last_bonding_candidate;
499 
500         if (last_bonding_candidate)
501                 kref_get(&last_bonding_candidate->refcount);
502         spin_unlock_bh(&orig_node->neigh_list_lock);
503 
504         return last_bonding_candidate;
505 }
506 
507 /**
508  * batadv_last_bonding_replace() - Replace last_bonding_candidate of orig_node
509  * @orig_node: originator node whose bonding candidates should be replaced
510  * @new_candidate: new bonding candidate or NULL
511  */
512 static void
513 batadv_last_bonding_replace(struct batadv_orig_node *orig_node,
514                             struct batadv_orig_ifinfo *new_candidate)
515 {
516         struct batadv_orig_ifinfo *old_candidate;
517 
518         spin_lock_bh(&orig_node->neigh_list_lock);
519         old_candidate = orig_node->last_bonding_candidate;
520 
521         if (new_candidate)
522                 kref_get(&new_candidate->refcount);
523         orig_node->last_bonding_candidate = new_candidate;
524         spin_unlock_bh(&orig_node->neigh_list_lock);
525 
526         if (old_candidate)
527                 batadv_orig_ifinfo_put(old_candidate);
528 }
529 
530 /**
531  * batadv_find_router() - find a suitable router for this originator
532  * @bat_priv: the bat priv with all the soft interface information
533  * @orig_node: the destination node
534  * @recv_if: pointer to interface this packet was received on
535  *
536  * Return: the router which should be used for this orig_node on
537  * this interface, or NULL if not available.
538  */
539 struct batadv_neigh_node *
540 batadv_find_router(struct batadv_priv *bat_priv,
541                    struct batadv_orig_node *orig_node,
542                    struct batadv_hard_iface *recv_if)
543 {
544         struct batadv_algo_ops *bao = bat_priv->algo_ops;
545         struct batadv_neigh_node *first_candidate_router = NULL;
546         struct batadv_neigh_node *next_candidate_router = NULL;
547         struct batadv_neigh_node *router, *cand_router = NULL;
548         struct batadv_neigh_node *last_cand_router = NULL;
549         struct batadv_orig_ifinfo *cand, *first_candidate = NULL;
550         struct batadv_orig_ifinfo *next_candidate = NULL;
551         struct batadv_orig_ifinfo *last_candidate;
552         bool last_candidate_found = false;
553 
554         if (!orig_node)
555                 return NULL;
556 
557         router = batadv_orig_router_get(orig_node, recv_if);
558 
559         if (!router)
560                 return router;
561 
562         /* only consider bonding for recv_if == BATADV_IF_DEFAULT (first hop)
563          * and if activated.
564          */
565         if (!(recv_if == BATADV_IF_DEFAULT && atomic_read(&bat_priv->bonding)))
566                 return router;
567 
568         /* bonding: loop through the list of possible routers found
569          * for the various outgoing interfaces and find a candidate after
570          * the last chosen bonding candidate (next_candidate). If no such
571          * router is found, use the first candidate found (the previously
572          * chosen bonding candidate might have been the last one in the list).
573          * If this can't be found either, return the previously chosen
574          * router - obviously there are no other candidates.
575          */
576         rcu_read_lock();
577         last_candidate = batadv_last_bonding_get(orig_node);
578         if (last_candidate)
579                 last_cand_router = rcu_dereference(last_candidate->router);
580 
581         hlist_for_each_entry_rcu(cand, &orig_node->ifinfo_list, list) {
582                 /* acquire some structures and references ... */
583                 if (!kref_get_unless_zero(&cand->refcount))
584                         continue;
585 
586                 cand_router = rcu_dereference(cand->router);
587                 if (!cand_router)
588                         goto next;
589 
590                 if (!kref_get_unless_zero(&cand_router->refcount)) {
591                         cand_router = NULL;
592                         goto next;
593                 }
594 
595                 /* alternative candidate should be good enough to be
596                  * considered
597                  */
598                 if (!bao->neigh.is_similar_or_better(cand_router,
599                                                      cand->if_outgoing, router,
600                                                      recv_if))
601                         goto next;
602 
603                 /* don't use the same router twice */
604                 if (last_cand_router == cand_router)
605                         goto next;
606 
607                 /* mark the first possible candidate */
608                 if (!first_candidate) {
609                         kref_get(&cand_router->refcount);
610                         kref_get(&cand->refcount);
611                         first_candidate = cand;
612                         first_candidate_router = cand_router;
613                 }
614 
615                 /* check if the loop has already passed the previously selected
616                  * candidate ... this function should select the next candidate
617                  * AFTER the previously used bonding candidate.
618                  */
619                 if (!last_candidate || last_candidate_found) {
620                         next_candidate = cand;
621                         next_candidate_router = cand_router;
622                         break;
623                 }
624 
625                 if (last_candidate == cand)
626                         last_candidate_found = true;
627 next:
628                 /* free references */
629                 if (cand_router) {
630                         batadv_neigh_node_put(cand_router);
631                         cand_router = NULL;
632                 }
633                 batadv_orig_ifinfo_put(cand);
634         }
635         rcu_read_unlock();
636 
637         /* After finding candidates, handle the three cases:
638          * 1) there is a next candidate, use that
639          * 2) there is no next candidate, use the first of the list
640          * 3) there is no candidate at all, return the default router
641          */
642         if (next_candidate) {
643                 batadv_neigh_node_put(router);
644 
645                 kref_get(&next_candidate_router->refcount);
646                 router = next_candidate_router;
647                 batadv_last_bonding_replace(orig_node, next_candidate);
648         } else if (first_candidate) {
649                 batadv_neigh_node_put(router);
650 
651                 kref_get(&first_candidate_router->refcount);
652                 router = first_candidate_router;
653                 batadv_last_bonding_replace(orig_node, first_candidate);
654         } else {
655                 batadv_last_bonding_replace(orig_node, NULL);
656         }
657 
658         /* cleanup of candidates */
659         if (first_candidate) {
660                 batadv_neigh_node_put(first_candidate_router);
661                 batadv_orig_ifinfo_put(first_candidate);
662         }
663 
664         if (next_candidate) {
665                 batadv_neigh_node_put(next_candidate_router);
666                 batadv_orig_ifinfo_put(next_candidate);
667         }
668 
669         if (last_candidate)
670                 batadv_orig_ifinfo_put(last_candidate);
671 
672         return router;
673 }
674 
675 static int batadv_route_unicast_packet(struct sk_buff *skb,
676                                        struct batadv_hard_iface *recv_if)
677 {
678         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
679         struct batadv_orig_node *orig_node = NULL;
680         struct batadv_unicast_packet *unicast_packet;
681         struct ethhdr *ethhdr = eth_hdr(skb);
682         int res, hdr_len, ret = NET_RX_DROP;
683         unsigned int len;
684 
685         unicast_packet = (struct batadv_unicast_packet *)skb->data;
686 
687         /* TTL exceeded */
688         if (unicast_packet->ttl < 2) {
689                 pr_debug("Warning - can't forward unicast packet from %pM to %pM: ttl exceeded\n",
690                          ethhdr->h_source, unicast_packet->dest);
691                 goto free_skb;
692         }
693 
694         /* get routing information */
695         orig_node = batadv_orig_hash_find(bat_priv, unicast_packet->dest);
696 
697         if (!orig_node)
698                 goto free_skb;
699 
700         /* create a copy of the skb, if needed, to modify it. */
701         if (skb_cow(skb, ETH_HLEN) < 0)
702                 goto put_orig_node;
703 
704         /* decrement ttl */
705         unicast_packet = (struct batadv_unicast_packet *)skb->data;
706         unicast_packet->ttl--;
707 
708         switch (unicast_packet->packet_type) {
709         case BATADV_UNICAST_4ADDR:
710                 hdr_len = sizeof(struct batadv_unicast_4addr_packet);
711                 break;
712         case BATADV_UNICAST:
713                 hdr_len = sizeof(struct batadv_unicast_packet);
714                 break;
715         default:
716                 /* other packet types not supported - yet */
717                 hdr_len = -1;
718                 break;
719         }
720 
721         if (hdr_len > 0)
722                 batadv_skb_set_priority(skb, hdr_len);
723 
724         len = skb->len;
725         res = batadv_send_skb_to_orig(skb, orig_node, recv_if);
726 
727         /* translate transmit result into receive result */
728         if (res == NET_XMIT_SUCCESS) {
729                 ret = NET_RX_SUCCESS;
730                 /* skb was transmitted and consumed */
731                 batadv_inc_counter(bat_priv, BATADV_CNT_FORWARD);
732                 batadv_add_counter(bat_priv, BATADV_CNT_FORWARD_BYTES,
733                                    len + ETH_HLEN);
734         }
735 
736         /* skb was consumed */
737         skb = NULL;
738 
739 put_orig_node:
740         batadv_orig_node_put(orig_node);
741 free_skb:
742         kfree_skb(skb);
743 
744         return ret;
745 }
746 
747 /**
748  * batadv_reroute_unicast_packet() - update the unicast header for re-routing
749  * @bat_priv: the bat priv with all the soft interface information
750  * @skb: unicast packet to process
751  * @unicast_packet: the unicast header to be updated
752  * @dst_addr: the payload destination
753  * @vid: VLAN identifier
754  *
755  * Search the translation table for dst_addr and update the unicast header with
756  * the new corresponding information (originator address where the destination
757  * client currently is and its known TTVN)
758  *
759  * Return: true if the packet header has been updated, false otherwise
760  */
761 static bool
762 batadv_reroute_unicast_packet(struct batadv_priv *bat_priv, struct sk_buff *skb,
763                               struct batadv_unicast_packet *unicast_packet,
764                               u8 *dst_addr, unsigned short vid)
765 {
766         struct batadv_orig_node *orig_node = NULL;
767         struct batadv_hard_iface *primary_if = NULL;
768         bool ret = false;
769         u8 *orig_addr, orig_ttvn;
770 
771         if (batadv_is_my_client(bat_priv, dst_addr, vid)) {
772                 primary_if = batadv_primary_if_get_selected(bat_priv);
773                 if (!primary_if)
774                         goto out;
775                 orig_addr = primary_if->net_dev->dev_addr;
776                 orig_ttvn = (u8)atomic_read(&bat_priv->tt.vn);
777         } else {
778                 orig_node = batadv_transtable_search(bat_priv, NULL, dst_addr,
779                                                      vid);
780                 if (!orig_node)
781                         goto out;
782 
783                 if (batadv_compare_eth(orig_node->orig, unicast_packet->dest))
784                         goto out;
785 
786                 orig_addr = orig_node->orig;
787                 orig_ttvn = (u8)atomic_read(&orig_node->last_ttvn);
788         }
789 
790         /* update the packet header */
791         skb_postpull_rcsum(skb, unicast_packet, sizeof(*unicast_packet));
792         ether_addr_copy(unicast_packet->dest, orig_addr);
793         unicast_packet->ttvn = orig_ttvn;
794         skb_postpush_rcsum(skb, unicast_packet, sizeof(*unicast_packet));
795 
796         ret = true;
797 out:
798         if (primary_if)
799                 batadv_hardif_put(primary_if);
800         if (orig_node)
801                 batadv_orig_node_put(orig_node);
802 
803         return ret;
804 }
805 
806 static bool batadv_check_unicast_ttvn(struct batadv_priv *bat_priv,
807                                       struct sk_buff *skb, int hdr_len)
808 {
809         struct batadv_unicast_packet *unicast_packet;
810         struct batadv_hard_iface *primary_if;
811         struct batadv_orig_node *orig_node;
812         u8 curr_ttvn, old_ttvn;
813         struct ethhdr *ethhdr;
814         unsigned short vid;
815         int is_old_ttvn;
816 
817         /* check if there is enough data before accessing it */
818         if (!pskb_may_pull(skb, hdr_len + ETH_HLEN))
819                 return false;
820 
821         /* create a copy of the skb (in case of for re-routing) to modify it. */
822         if (skb_cow(skb, sizeof(*unicast_packet)) < 0)
823                 return false;
824 
825         unicast_packet = (struct batadv_unicast_packet *)skb->data;
826         vid = batadv_get_vid(skb, hdr_len);
827         ethhdr = (struct ethhdr *)(skb->data + hdr_len);
828 
829         /* check if the destination client was served by this node and it is now
830          * roaming. In this case, it means that the node has got a ROAM_ADV
831          * message and that it knows the new destination in the mesh to re-route
832          * the packet to
833          */
834         if (batadv_tt_local_client_is_roaming(bat_priv, ethhdr->h_dest, vid)) {
835                 if (batadv_reroute_unicast_packet(bat_priv, skb, unicast_packet,
836                                                   ethhdr->h_dest, vid))
837                         batadv_dbg_ratelimited(BATADV_DBG_TT,
838                                                bat_priv,
839                                                "Rerouting unicast packet to %pM (dst=%pM): Local Roaming\n",
840                                                unicast_packet->dest,
841                                                ethhdr->h_dest);
842                 /* at this point the mesh destination should have been
843                  * substituted with the originator address found in the global
844                  * table. If not, let the packet go untouched anyway because
845                  * there is nothing the node can do
846                  */
847                 return true;
848         }
849 
850         /* retrieve the TTVN known by this node for the packet destination. This
851          * value is used later to check if the node which sent (or re-routed
852          * last time) the packet had an updated information or not
853          */
854         curr_ttvn = (u8)atomic_read(&bat_priv->tt.vn);
855         if (!batadv_is_my_mac(bat_priv, unicast_packet->dest)) {
856                 orig_node = batadv_orig_hash_find(bat_priv,
857                                                   unicast_packet->dest);
858                 /* if it is not possible to find the orig_node representing the
859                  * destination, the packet can immediately be dropped as it will
860                  * not be possible to deliver it
861                  */
862                 if (!orig_node)
863                         return false;
864 
865                 curr_ttvn = (u8)atomic_read(&orig_node->last_ttvn);
866                 batadv_orig_node_put(orig_node);
867         }
868 
869         /* check if the TTVN contained in the packet is fresher than what the
870          * node knows
871          */
872         is_old_ttvn = batadv_seq_before(unicast_packet->ttvn, curr_ttvn);
873         if (!is_old_ttvn)
874                 return true;
875 
876         old_ttvn = unicast_packet->ttvn;
877         /* the packet was forged based on outdated network information. Its
878          * destination can possibly be updated and forwarded towards the new
879          * target host
880          */
881         if (batadv_reroute_unicast_packet(bat_priv, skb, unicast_packet,
882                                           ethhdr->h_dest, vid)) {
883                 batadv_dbg_ratelimited(BATADV_DBG_TT, bat_priv,
884                                        "Rerouting unicast packet to %pM (dst=%pM): TTVN mismatch old_ttvn=%u new_ttvn=%u\n",
885                                        unicast_packet->dest, ethhdr->h_dest,
886                                        old_ttvn, curr_ttvn);
887                 return true;
888         }
889 
890         /* the packet has not been re-routed: either the destination is
891          * currently served by this node or there is no destination at all and
892          * it is possible to drop the packet
893          */
894         if (!batadv_is_my_client(bat_priv, ethhdr->h_dest, vid))
895                 return false;
896 
897         /* update the header in order to let the packet be delivered to this
898          * node's soft interface
899          */
900         primary_if = batadv_primary_if_get_selected(bat_priv);
901         if (!primary_if)
902                 return false;
903 
904         /* update the packet header */
905         skb_postpull_rcsum(skb, unicast_packet, sizeof(*unicast_packet));
906         ether_addr_copy(unicast_packet->dest, primary_if->net_dev->dev_addr);
907         unicast_packet->ttvn = curr_ttvn;
908         skb_postpush_rcsum(skb, unicast_packet, sizeof(*unicast_packet));
909 
910         batadv_hardif_put(primary_if);
911 
912         return true;
913 }
914 
915 /**
916  * batadv_recv_unhandled_unicast_packet() - receive and process packets which
917  *      are in the unicast number space but not yet known to the implementation
918  * @skb: unicast tvlv packet to process
919  * @recv_if: pointer to interface this packet was received on
920  *
921  * Return: NET_RX_SUCCESS if the packet has been consumed or NET_RX_DROP
922  * otherwise.
923  */
924 int batadv_recv_unhandled_unicast_packet(struct sk_buff *skb,
925                                          struct batadv_hard_iface *recv_if)
926 {
927         struct batadv_unicast_packet *unicast_packet;
928         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
929         int check, hdr_size = sizeof(*unicast_packet);
930 
931         check = batadv_check_unicast_packet(bat_priv, skb, hdr_size);
932         if (check < 0)
933                 goto free_skb;
934 
935         /* we don't know about this type, drop it. */
936         unicast_packet = (struct batadv_unicast_packet *)skb->data;
937         if (batadv_is_my_mac(bat_priv, unicast_packet->dest))
938                 goto free_skb;
939 
940         return batadv_route_unicast_packet(skb, recv_if);
941 
942 free_skb:
943         kfree_skb(skb);
944         return NET_RX_DROP;
945 }
946 
947 /**
948  * batadv_recv_unicast_packet() - Process incoming unicast packet
949  * @skb: incoming packet buffer
950  * @recv_if: incoming hard interface
951  *
952  * Return: NET_RX_SUCCESS on success or NET_RX_DROP in case of failure
953  */
954 int batadv_recv_unicast_packet(struct sk_buff *skb,
955                                struct batadv_hard_iface *recv_if)
956 {
957         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
958         struct batadv_unicast_packet *unicast_packet;
959         struct batadv_unicast_4addr_packet *unicast_4addr_packet;
960         u8 *orig_addr, *orig_addr_gw;
961         struct batadv_orig_node *orig_node = NULL, *orig_node_gw = NULL;
962         int check, hdr_size = sizeof(*unicast_packet);
963         enum batadv_subtype subtype;
964         int ret = NET_RX_DROP;
965         bool is4addr, is_gw;
966 
967         unicast_packet = (struct batadv_unicast_packet *)skb->data;
968         is4addr = unicast_packet->packet_type == BATADV_UNICAST_4ADDR;
969         /* the caller function should have already pulled 2 bytes */
970         if (is4addr)
971                 hdr_size = sizeof(*unicast_4addr_packet);
972 
973         /* function returns -EREMOTE for promiscuous packets */
974         check = batadv_check_unicast_packet(bat_priv, skb, hdr_size);
975 
976         /* Even though the packet is not for us, we might save it to use for
977          * decoding a later received coded packet
978          */
979         if (check == -EREMOTE)
980                 batadv_nc_skb_store_sniffed_unicast(bat_priv, skb);
981 
982         if (check < 0)
983                 goto free_skb;
984         if (!batadv_check_unicast_ttvn(bat_priv, skb, hdr_size))
985                 goto free_skb;
986 
987         unicast_packet = (struct batadv_unicast_packet *)skb->data;
988 
989         /* packet for me */
990         if (batadv_is_my_mac(bat_priv, unicast_packet->dest)) {
991                 /* If this is a unicast packet from another backgone gw,
992                  * drop it.
993                  */
994                 orig_addr_gw = eth_hdr(skb)->h_source;
995                 orig_node_gw = batadv_orig_hash_find(bat_priv, orig_addr_gw);
996                 if (orig_node_gw) {
997                         is_gw = batadv_bla_is_backbone_gw(skb, orig_node_gw,
998                                                           hdr_size);
999                         batadv_orig_node_put(orig_node_gw);
1000                         if (is_gw) {
1001                                 batadv_dbg(BATADV_DBG_BLA, bat_priv,
1002                                            "%s(): Dropped unicast pkt received from another backbone gw %pM.\n",
1003                                            __func__, orig_addr_gw);
1004                                 goto free_skb;
1005                         }
1006                 }
1007 
1008                 if (is4addr) {
1009                         unicast_4addr_packet =
1010                                 (struct batadv_unicast_4addr_packet *)skb->data;
1011                         subtype = unicast_4addr_packet->subtype;
1012                         batadv_dat_inc_counter(bat_priv, subtype);
1013 
1014                         /* Only payload data should be considered for speedy
1015                          * join. For example, DAT also uses unicast 4addr
1016                          * types, but those packets should not be considered
1017                          * for speedy join, since the clients do not actually
1018                          * reside at the sending originator.
1019                          */
1020                         if (subtype == BATADV_P_DATA) {
1021                                 orig_addr = unicast_4addr_packet->src;
1022                                 orig_node = batadv_orig_hash_find(bat_priv,
1023                                                                   orig_addr);
1024                         }
1025                 }
1026 
1027                 if (batadv_dat_snoop_incoming_arp_request(bat_priv, skb,
1028                                                           hdr_size))
1029                         goto rx_success;
1030                 if (batadv_dat_snoop_incoming_arp_reply(bat_priv, skb,
1031                                                         hdr_size))
1032                         goto rx_success;
1033 
1034                 batadv_dat_snoop_incoming_dhcp_ack(bat_priv, skb, hdr_size);
1035 
1036                 batadv_interface_rx(recv_if->soft_iface, skb, hdr_size,
1037                                     orig_node);
1038 
1039 rx_success:
1040                 if (orig_node)
1041                         batadv_orig_node_put(orig_node);
1042 
1043                 return NET_RX_SUCCESS;
1044         }
1045 
1046         ret = batadv_route_unicast_packet(skb, recv_if);
1047         /* skb was consumed */
1048         skb = NULL;
1049 
1050 free_skb:
1051         kfree_skb(skb);
1052 
1053         return ret;
1054 }
1055 
1056 /**
1057  * batadv_recv_unicast_tvlv() - receive and process unicast tvlv packets
1058  * @skb: unicast tvlv packet to process
1059  * @recv_if: pointer to interface this packet was received on
1060  *
1061  * Return: NET_RX_SUCCESS if the packet has been consumed or NET_RX_DROP
1062  * otherwise.
1063  */
1064 int batadv_recv_unicast_tvlv(struct sk_buff *skb,
1065                              struct batadv_hard_iface *recv_if)
1066 {
1067         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1068         struct batadv_unicast_tvlv_packet *unicast_tvlv_packet;
1069         unsigned char *tvlv_buff;
1070         u16 tvlv_buff_len;
1071         int hdr_size = sizeof(*unicast_tvlv_packet);
1072         int ret = NET_RX_DROP;
1073 
1074         if (batadv_check_unicast_packet(bat_priv, skb, hdr_size) < 0)
1075                 goto free_skb;
1076 
1077         /* the header is likely to be modified while forwarding */
1078         if (skb_cow(skb, hdr_size) < 0)
1079                 goto free_skb;
1080 
1081         /* packet needs to be linearized to access the tvlv content */
1082         if (skb_linearize(skb) < 0)
1083                 goto free_skb;
1084 
1085         unicast_tvlv_packet = (struct batadv_unicast_tvlv_packet *)skb->data;
1086 
1087         tvlv_buff = (unsigned char *)(skb->data + hdr_size);
1088         tvlv_buff_len = ntohs(unicast_tvlv_packet->tvlv_len);
1089 
1090         if (tvlv_buff_len > skb->len - hdr_size)
1091                 goto free_skb;
1092 
1093         ret = batadv_tvlv_containers_process(bat_priv, false, NULL,
1094                                              unicast_tvlv_packet->src,
1095                                              unicast_tvlv_packet->dst,
1096                                              tvlv_buff, tvlv_buff_len);
1097 
1098         if (ret != NET_RX_SUCCESS) {
1099                 ret = batadv_route_unicast_packet(skb, recv_if);
1100                 /* skb was consumed */
1101                 skb = NULL;
1102         }
1103 
1104 free_skb:
1105         kfree_skb(skb);
1106 
1107         return ret;
1108 }
1109 
1110 /**
1111  * batadv_recv_frag_packet() - process received fragment
1112  * @skb: the received fragment
1113  * @recv_if: interface that the skb is received on
1114  *
1115  * This function does one of the three following things: 1) Forward fragment, if
1116  * the assembled packet will exceed our MTU; 2) Buffer fragment, if we till
1117  * lack further fragments; 3) Merge fragments, if we have all needed parts.
1118  *
1119  * Return: NET_RX_DROP if the skb is not consumed, NET_RX_SUCCESS otherwise.
1120  */
1121 int batadv_recv_frag_packet(struct sk_buff *skb,
1122                             struct batadv_hard_iface *recv_if)
1123 {
1124         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1125         struct batadv_orig_node *orig_node_src = NULL;
1126         struct batadv_frag_packet *frag_packet;
1127         int ret = NET_RX_DROP;
1128 
1129         if (batadv_check_unicast_packet(bat_priv, skb,
1130                                         sizeof(*frag_packet)) < 0)
1131                 goto free_skb;
1132 
1133         frag_packet = (struct batadv_frag_packet *)skb->data;
1134         orig_node_src = batadv_orig_hash_find(bat_priv, frag_packet->orig);
1135         if (!orig_node_src)
1136                 goto free_skb;
1137 
1138         skb->priority = frag_packet->priority + 256;
1139 
1140         /* Route the fragment if it is not for us and too big to be merged. */
1141         if (!batadv_is_my_mac(bat_priv, frag_packet->dest) &&
1142             batadv_frag_skb_fwd(skb, recv_if, orig_node_src)) {
1143                 /* skb was consumed */
1144                 skb = NULL;
1145                 ret = NET_RX_SUCCESS;
1146                 goto put_orig_node;
1147         }
1148 
1149         batadv_inc_counter(bat_priv, BATADV_CNT_FRAG_RX);
1150         batadv_add_counter(bat_priv, BATADV_CNT_FRAG_RX_BYTES, skb->len);
1151 
1152         /* Add fragment to buffer and merge if possible. */
1153         if (!batadv_frag_skb_buffer(&skb, orig_node_src))
1154                 goto put_orig_node;
1155 
1156         /* Deliver merged packet to the appropriate handler, if it was
1157          * merged
1158          */
1159         if (skb) {
1160                 batadv_batman_skb_recv(skb, recv_if->net_dev,
1161                                        &recv_if->batman_adv_ptype, NULL);
1162                 /* skb was consumed */
1163                 skb = NULL;
1164         }
1165 
1166         ret = NET_RX_SUCCESS;
1167 
1168 put_orig_node:
1169         batadv_orig_node_put(orig_node_src);
1170 free_skb:
1171         kfree_skb(skb);
1172 
1173         return ret;
1174 }
1175 
1176 /**
1177  * batadv_recv_bcast_packet() - Process incoming broadcast packet
1178  * @skb: incoming packet buffer
1179  * @recv_if: incoming hard interface
1180  *
1181  * Return: NET_RX_SUCCESS on success or NET_RX_DROP in case of failure
1182  */
1183 int batadv_recv_bcast_packet(struct sk_buff *skb,
1184                              struct batadv_hard_iface *recv_if)
1185 {
1186         struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
1187         struct batadv_orig_node *orig_node = NULL;
1188         struct batadv_bcast_packet *bcast_packet;
1189         struct ethhdr *ethhdr;
1190         int hdr_size = sizeof(*bcast_packet);
1191         int ret = NET_RX_DROP;
1192         s32 seq_diff;
1193         u32 seqno;
1194 
1195         /* drop packet if it has not necessary minimum size */
1196         if (unlikely(!pskb_may_pull(skb, hdr_size)))
1197                 goto free_skb;
1198 
1199         ethhdr = eth_hdr(skb);
1200 
1201         /* packet with broadcast indication but unicast recipient */
1202         if (!is_broadcast_ether_addr(ethhdr->h_dest))
1203                 goto free_skb;
1204 
1205         /* packet with broadcast/multicast sender address */
1206         if (is_multicast_ether_addr(ethhdr->h_source))
1207                 goto free_skb;
1208 
1209         /* ignore broadcasts sent by myself */
1210         if (batadv_is_my_mac(bat_priv, ethhdr->h_source))
1211                 goto free_skb;
1212 
1213         bcast_packet = (struct batadv_bcast_packet *)skb->data;
1214 
1215         /* ignore broadcasts originated by myself */
1216         if (batadv_is_my_mac(bat_priv, bcast_packet->orig))
1217                 goto free_skb;
1218 
1219         if (bcast_packet->ttl < 2)
1220                 goto free_skb;
1221 
1222         orig_node = batadv_orig_hash_find(bat_priv, bcast_packet->orig);
1223 
1224         if (!orig_node)
1225                 goto free_skb;
1226 
1227         spin_lock_bh(&orig_node->bcast_seqno_lock);
1228 
1229         seqno = ntohl(bcast_packet->seqno);
1230         /* check whether the packet is a duplicate */
1231         if (batadv_test_bit(orig_node->bcast_bits, orig_node->last_bcast_seqno,
1232                             seqno))
1233                 goto spin_unlock;
1234 
1235         seq_diff = seqno - orig_node->last_bcast_seqno;
1236 
1237         /* check whether the packet is old and the host just restarted. */
1238         if (batadv_window_protected(bat_priv, seq_diff,
1239                                     BATADV_BCAST_MAX_AGE,
1240                                     &orig_node->bcast_seqno_reset, NULL))
1241                 goto spin_unlock;
1242 
1243         /* mark broadcast in flood history, update window position
1244          * if required.
1245          */
1246         if (batadv_bit_get_packet(bat_priv, orig_node->bcast_bits, seq_diff, 1))
1247                 orig_node->last_bcast_seqno = seqno;
1248 
1249         spin_unlock_bh(&orig_node->bcast_seqno_lock);
1250 
1251         /* check whether this has been sent by another originator before */
1252         if (batadv_bla_check_bcast_duplist(bat_priv, skb))
1253                 goto free_skb;
1254 
1255         batadv_skb_set_priority(skb, sizeof(struct batadv_bcast_packet));
1256 
1257         /* rebroadcast packet */
1258         batadv_add_bcast_packet_to_list(bat_priv, skb, 1, false);
1259 
1260         /* don't hand the broadcast up if it is from an originator
1261          * from the same backbone.
1262          */
1263         if (batadv_bla_is_backbone_gw(skb, orig_node, hdr_size))
1264                 goto free_skb;
1265 
1266         if (batadv_dat_snoop_incoming_arp_request(bat_priv, skb, hdr_size))
1267                 goto rx_success;
1268         if (batadv_dat_snoop_incoming_arp_reply(bat_priv, skb, hdr_size))
1269                 goto rx_success;
1270 
1271         batadv_dat_snoop_incoming_dhcp_ack(bat_priv, skb, hdr_size);
1272 
1273         /* broadcast for me */
1274         batadv_interface_rx(recv_if->soft_iface, skb, hdr_size, orig_node);
1275 
1276 rx_success:
1277         ret = NET_RX_SUCCESS;
1278         goto out;
1279 
1280 spin_unlock:
1281         spin_unlock_bh(&orig_node->bcast_seqno_lock);
1282 free_skb:
1283         kfree_skb(skb);
1284 out:
1285         if (orig_node)
1286                 batadv_orig_node_put(orig_node);
1287         return ret;
1288 }
1289 

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