net/batman-adv/send.c

   1 /* Copyright (C) 2007-2016  B.A.T.M.A.N. contributors:
   2  *
   3  * Marek Lindner, Simon Wunderlich
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of version 2 of the GNU General Public
   7  * License as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include "send.h"
  19 #include "main.h"
  20
  21 #include <linux/atomic.h>
  22 #include <linux/byteorder/generic.h>
  23 #include <linux/errno.h>
  24 #include <linux/etherdevice.h>
  25 #include <linux/fs.h>
  26 #include <linux/if.h>
  27 #include <linux/if_ether.h>
  28 #include <linux/jiffies.h>
  29 #include <linux/kernel.h>
  30 #include <linux/kref.h>
  31 #include <linux/list.h>
  32 #include <linux/netdevice.h>
  33 #include <linux/printk.h>
  34 #include <linux/rculist.h>
  35 #include <linux/rcupdate.h>
  36 #include <linux/skbuff.h>
  37 #include <linux/slab.h>
  38 #include <linux/spinlock.h>
  39 #include <linux/stddef.h>
  40 #include <linux/workqueue.h>
  41
  42 #include "distributed-arp-table.h"
  43 #include "fragmentation.h"
  44 #include "gateway_client.h"
  45 #include "hard-interface.h"
  46 #include "log.h"
  47 #include "network-coding.h"
  48 #include "originator.h"
  49 #include "routing.h"
  50 #include "soft-interface.h"
  51 #include "translation-table.h"
  52
  53 static void batadv_send_outstanding_bcast_packet(struct work_struct *work);
  54
  55 /**
  56  * batadv_send_skb_packet - send an already prepared packet
  57  * @skb: the packet to send
  58  * @hard_iface: the interface to use to send the broadcast packet
  59  * @dst_addr: the payload destination
  60  *
  61  * Send out an already prepared packet to the given neighbor or broadcast it
  62  * using the specified interface. Either hard_iface or neigh_node must be not
  63  * NULL.
  64  * If neigh_node is NULL, then the packet is broadcasted using hard_iface,
  65  * otherwise it is sent as unicast to the given neighbor.
  66  *
  67  * Return: NET_TX_DROP in case of error or the result of dev_queue_xmit(skb)
  68  * otherwise
  69  */
  70 int batadv_send_skb_packet(struct sk_buff *skb,
  71                            struct batadv_hard_iface *hard_iface,
  72                            const u8 *dst_addr)
  73 {
  74         struct batadv_priv *bat_priv;
  75         struct ethhdr *ethhdr;
  76         int ret;
  77
  78         bat_priv = netdev_priv(hard_iface->soft_iface);
  79
  80         if (hard_iface->if_status != BATADV_IF_ACTIVE)
  81                 goto send_skb_err;
  82
  83         if (unlikely(!hard_iface->net_dev))
  84                 goto send_skb_err;
  85
  86         if (!(hard_iface->net_dev->flags & IFF_UP)) {
  87                 pr_warn("Interface %s is not up - can't send packet via that interface!\n",
  88                         hard_iface->net_dev->name);
  89                 goto send_skb_err;
  90         }
  91
  92         /* push to the ethernet header. */
  93         if (batadv_skb_head_push(skb, ETH_HLEN) < 0)
  94                 goto send_skb_err;
  95
  96         skb_reset_mac_header(skb);
  97
  98         ethhdr = eth_hdr(skb);
  99         ether_addr_copy(ethhdr->h_source, hard_iface->net_dev->dev_addr);
 100         ether_addr_copy(ethhdr->h_dest, dst_addr);
 101         ethhdr->h_proto = htons(ETH_P_BATMAN);
 102
 103         skb_set_network_header(skb, ETH_HLEN);
 104         skb->protocol = htons(ETH_P_BATMAN);
 105
 106         skb->dev = hard_iface->net_dev;
 107
 108         /* Save a clone of the skb to use when decoding coded packets */
 109         batadv_nc_skb_store_for_decoding(bat_priv, skb);
 110
 111         /* dev_queue_xmit() returns a negative result on error.  However on
 112          * congestion and traffic shaping, it drops and returns NET_XMIT_DROP
 113          * (which is > 0). This will not be treated as an error.
 114          *
 115          * a negative value cannot be returned because it could be interepreted
 116          * as not consumed skb by callers of batadv_send_skb_to_orig.
 117          */
 118         ret = dev_queue_xmit(skb);
 119         if (ret < 0)
 120                 ret = NET_XMIT_DROP;
 121
 122         return ret;
 123 send_skb_err:
 124         kfree_skb(skb);
 125         return NET_XMIT_DROP;
 126 }
 127
 128 int batadv_send_broadcast_skb(struct sk_buff *skb,
 129                               struct batadv_hard_iface *hard_iface)
 130 {
 131         return batadv_send_skb_packet(skb, hard_iface, batadv_broadcast_addr);
 132 }
 133
 134 int batadv_send_unicast_skb(struct sk_buff *skb,
 135                             struct batadv_neigh_node *neigh)
 136 {
 137 #ifdef CONFIG_BATMAN_ADV_BATMAN_V
 138         struct batadv_hardif_neigh_node *hardif_neigh;
 139 #endif
 140         int ret;
 141
 142         ret = batadv_send_skb_packet(skb, neigh->if_incoming, neigh->addr);
 143
 144 #ifdef CONFIG_BATMAN_ADV_BATMAN_V
 145         hardif_neigh = batadv_hardif_neigh_get(neigh->if_incoming, neigh->addr);
 146
 147         if ((hardif_neigh) && (ret != NET_XMIT_DROP))
 148                 hardif_neigh->bat_v.last_unicast_tx = jiffies;
 149
 150         if (hardif_neigh)
 151                 batadv_hardif_neigh_put(hardif_neigh);
 152 #endif
 153
 154         return ret;
 155 }
 156
 157 /**
 158  * batadv_send_skb_to_orig - Lookup next-hop and transmit skb.
 159  * @skb: Packet to be transmitted.
 160  * @orig_node: Final destination of the packet.
 161  * @recv_if: Interface used when receiving the packet (can be NULL).
 162  *
 163  * Looks up the best next-hop towards the passed originator and passes the
 164  * skb on for preparation of MAC header. If the packet originated from this
 165  * host, NULL can be passed as recv_if and no interface alternating is
 166  * attempted.
 167  *
 168  * Return: -1 on failure (and the skb is not consumed), -EINPROGRESS if the
 169  * skb is buffered for later transmit or the NET_XMIT status returned by the
 170  * lower routine if the packet has been passed down.
 171  *
 172  * If the returning value is not -1 the skb has been consumed.
 173  */
 174 int batadv_send_skb_to_orig(struct sk_buff *skb,
 175                             struct batadv_orig_node *orig_node,
 176                             struct batadv_hard_iface *recv_if)
 177 {
 178         struct batadv_priv *bat_priv = orig_node->bat_priv;
 179         struct batadv_neigh_node *neigh_node;
 180         int ret = -1;
 181
 182         /* batadv_find_router() increases neigh_nodes refcount if found. */
 183         neigh_node = batadv_find_router(bat_priv, orig_node, recv_if);
 184         if (!neigh_node)
 185                 goto out;
 186
 187         /* Check if the skb is too large to send in one piece and fragment
 188          * it if needed.
 189          */
 190         if (atomic_read(&bat_priv->fragmentation) &&
 191             skb->len > neigh_node->if_incoming->net_dev->mtu) {
 192                 /* Fragment and send packet. */
 193                 ret = batadv_frag_send_packet(skb, orig_node, neigh_node);
 194
 195                 goto out;
 196         }
 197
 198         /* try to network code the packet, if it is received on an interface
 199          * (i.e. being forwarded). If the packet originates from this node or if
 200          * network coding fails, then send the packet as usual.
 201          */
 202         if (recv_if && batadv_nc_skb_forward(skb, neigh_node))
 203                 ret = -EINPROGRESS;
 204         else
 205                 ret = batadv_send_unicast_skb(skb, neigh_node);
 206
 207 out:
 208         if (neigh_node)
 209                 batadv_neigh_node_put(neigh_node);
 210
 211         return ret;
 212 }
 213
 214 /**
 215  * batadv_send_skb_push_fill_unicast - extend the buffer and initialize the
 216  *  common fields for unicast packets
 217  * @skb: the skb carrying the unicast header to initialize
 218  * @hdr_size: amount of bytes to push at the beginning of the skb
 219  * @orig_node: the destination node
 220  *
 221  * Return: false if the buffer extension was not possible or true otherwise.
 222  */
 223 static bool
 224 batadv_send_skb_push_fill_unicast(struct sk_buff *skb, int hdr_size,
 225                                   struct batadv_orig_node *orig_node)
 226 {
 227         struct batadv_unicast_packet *unicast_packet;
 228         u8 ttvn = (u8)atomic_read(&orig_node->last_ttvn);
 229
 230         if (batadv_skb_head_push(skb, hdr_size) < 0)
 231                 return false;
 232
 233         unicast_packet = (struct batadv_unicast_packet *)skb->data;
 234         unicast_packet->version = BATADV_COMPAT_VERSION;
 235         /* batman packet type: unicast */
 236         unicast_packet->packet_type = BATADV_UNICAST;
 237         /* set unicast ttl */
 238         unicast_packet->ttl = BATADV_TTL;
 239         /* copy the destination for faster routing */
 240         ether_addr_copy(unicast_packet->dest, orig_node->orig);
 241         /* set the destination tt version number */
 242         unicast_packet->ttvn = ttvn;
 243
 244         return true;
 245 }
 246
 247 /**
 248  * batadv_send_skb_prepare_unicast - encapsulate an skb with a unicast header
 249  * @skb: the skb containing the payload to encapsulate
 250  * @orig_node: the destination node
 251  *
 252  * Return: false if the payload could not be encapsulated or true otherwise.
 253  */
 254 static bool batadv_send_skb_prepare_unicast(struct sk_buff *skb,
 255                                             struct batadv_orig_node *orig_node)
 256 {
 257         size_t uni_size = sizeof(struct batadv_unicast_packet);
 258
 259         return batadv_send_skb_push_fill_unicast(skb, uni_size, orig_node);
 260 }
 261
 262 /**
 263  * batadv_send_skb_prepare_unicast_4addr - encapsulate an skb with a
 264  *  unicast 4addr header
 265  * @bat_priv: the bat priv with all the soft interface information
 266  * @skb: the skb containing the payload to encapsulate
 267  * @orig: the destination node
 268  * @packet_subtype: the unicast 4addr packet subtype to use
 269  *
 270  * Return: false if the payload could not be encapsulated or true otherwise.
 271  */
 272 bool batadv_send_skb_prepare_unicast_4addr(struct batadv_priv *bat_priv,
 273                                            struct sk_buff *skb,
 274                                            struct batadv_orig_node *orig,
 275                                            int packet_subtype)
 276 {
 277         struct batadv_hard_iface *primary_if;
 278         struct batadv_unicast_4addr_packet *uc_4addr_packet;
 279         bool ret = false;
 280
 281         primary_if = batadv_primary_if_get_selected(bat_priv);
 282         if (!primary_if)
 283                 goto out;
 284
 285         /* Pull the header space and fill the unicast_packet substructure.
 286          * We can do that because the first member of the uc_4addr_packet
 287          * is of type struct unicast_packet
 288          */
 289         if (!batadv_send_skb_push_fill_unicast(skb, sizeof(*uc_4addr_packet),
 290                                                orig))
 291                 goto out;
 292
 293         uc_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data;
 294         uc_4addr_packet->u.packet_type = BATADV_UNICAST_4ADDR;
 295         ether_addr_copy(uc_4addr_packet->src, primary_if->net_dev->dev_addr);
 296         uc_4addr_packet->subtype = packet_subtype;
 297         uc_4addr_packet->reserved = 0;
 298
 299         ret = true;
 300 out:
 301         if (primary_if)
 302                 batadv_hardif_put(primary_if);
 303         return ret;
 304 }
 305
 306 /**
 307  * batadv_send_skb_unicast - encapsulate and send an skb via unicast
 308  * @bat_priv: the bat priv with all the soft interface information
 309  * @skb: payload to send
 310  * @packet_type: the batman unicast packet type to use
 311  * @packet_subtype: the unicast 4addr packet subtype (only relevant for unicast
 312  *  4addr packets)
 313  * @orig_node: the originator to send the packet to
 314  * @vid: the vid to be used to search the translation table
 315  *
 316  * Wrap the given skb into a batman-adv unicast or unicast-4addr header
 317  * depending on whether BATADV_UNICAST or BATADV_UNICAST_4ADDR was supplied
 318  * as packet_type. Then send this frame to the given orig_node and release a
 319  * reference to this orig_node.
 320  *
 321  * Return: NET_XMIT_DROP in case of error or NET_XMIT_SUCCESS otherwise.
 322  */
 323 int batadv_send_skb_unicast(struct batadv_priv *bat_priv,
 324                             struct sk_buff *skb, int packet_type,
 325                             int packet_subtype,
 326                             struct batadv_orig_node *orig_node,
 327                             unsigned short vid)
 328 {
 329         struct batadv_unicast_packet *unicast_packet;
 330         struct ethhdr *ethhdr;
 331         int res, ret = NET_XMIT_DROP;
 332
 333         if (!orig_node)
 334                 goto out;
 335
 336         switch (packet_type) {
 337         case BATADV_UNICAST:
 338                 if (!batadv_send_skb_prepare_unicast(skb, orig_node))
 339                         goto out;
 340                 break;
 341         case BATADV_UNICAST_4ADDR:
 342                 if (!batadv_send_skb_prepare_unicast_4addr(bat_priv, skb,
 343                                                            orig_node,
 344                                                            packet_subtype))
 345                         goto out;
 346                 break;
 347         default:
 348                 /* this function supports UNICAST and UNICAST_4ADDR only. It
 349                  * should never be invoked with any other packet type
 350                  */
 351                 goto out;
 352         }
 353
 354         /* skb->data might have been reallocated by
 355          * batadv_send_skb_prepare_unicast{,_4addr}()
 356          */
 357         ethhdr = eth_hdr(skb);
 358         unicast_packet = (struct batadv_unicast_packet *)skb->data;
 359
 360         /* inform the destination node that we are still missing a correct route
 361          * for this client. The destination will receive this packet and will
 362          * try to reroute it because the ttvn contained in the header is less
 363          * than the current one
 364          */
 365         if (batadv_tt_global_client_is_roaming(bat_priv, ethhdr->h_dest, vid))
 366                 unicast_packet->ttvn = unicast_packet->ttvn - 1;
 367
 368         res = batadv_send_skb_to_orig(skb, orig_node, NULL);
 369         if (res != -1)
 370                 ret = NET_XMIT_SUCCESS;
 371
 372 out:
 373         if (orig_node)
 374                 batadv_orig_node_put(orig_node);
 375         if (ret == NET_XMIT_DROP)
 376                 kfree_skb(skb);
 377         return ret;
 378 }
 379
 380 /**
 381  * batadv_send_skb_via_tt_generic - send an skb via TT lookup
 382  * @bat_priv: the bat priv with all the soft interface information
 383  * @skb: payload to send
 384  * @packet_type: the batman unicast packet type to use
 385  * @packet_subtype: the unicast 4addr packet subtype (only relevant for unicast
 386  *  4addr packets)
 387  * @dst_hint: can be used to override the destination contained in the skb
 388  * @vid: the vid to be used to search the translation table
 389  *
 390  * Look up the recipient node for the destination address in the ethernet
 391  * header via the translation table. Wrap the given skb into a batman-adv
 392  * unicast or unicast-4addr header depending on whether BATADV_UNICAST or
 393  * BATADV_UNICAST_4ADDR was supplied as packet_type. Then send this frame
 394  * to the according destination node.
 395  *
 396  * Return: NET_XMIT_DROP in case of error or NET_XMIT_SUCCESS otherwise.
 397  */
 398 int batadv_send_skb_via_tt_generic(struct batadv_priv *bat_priv,
 399                                    struct sk_buff *skb, int packet_type,
 400                                    int packet_subtype, u8 *dst_hint,
 401                                    unsigned short vid)
 402 {
 403         struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
 404         struct batadv_orig_node *orig_node;
 405         u8 *src, *dst;
 406
 407         src = ethhdr->h_source;
 408         dst = ethhdr->h_dest;
 409
 410         /* if we got an hint! let's send the packet to this client (if any) */
 411         if (dst_hint) {
 412                 src = NULL;
 413                 dst = dst_hint;
 414         }
 415         orig_node = batadv_transtable_search(bat_priv, src, dst, vid);
 416
 417         return batadv_send_skb_unicast(bat_priv, skb, packet_type,
 418                                        packet_subtype, orig_node, vid);
 419 }
 420
 421 /**
 422  * batadv_send_skb_via_gw - send an skb via gateway lookup
 423  * @bat_priv: the bat priv with all the soft interface information
 424  * @skb: payload to send
 425  * @vid: the vid to be used to search the translation table
 426  *
 427  * Look up the currently selected gateway. Wrap the given skb into a batman-adv
 428  * unicast header and send this frame to this gateway node.
 429  *
 430  * Return: NET_XMIT_DROP in case of error or NET_XMIT_SUCCESS otherwise.
 431  */
 432 int batadv_send_skb_via_gw(struct batadv_priv *bat_priv, struct sk_buff *skb,
 433                            unsigned short vid)
 434 {
 435         struct batadv_orig_node *orig_node;
 436
 437         orig_node = batadv_gw_get_selected_orig(bat_priv);
 438         return batadv_send_skb_unicast(bat_priv, skb, BATADV_UNICAST_4ADDR,
 439                                        BATADV_P_DATA, orig_node, vid);
 440 }
 441
 442 void batadv_forw_packet_free(struct batadv_forw_packet *forw_packet)
 443 {
 444         kfree_skb(forw_packet->skb);
 445         if (forw_packet->if_incoming)
 446                 batadv_hardif_put(forw_packet->if_incoming);
 447         if (forw_packet->if_outgoing)
 448                 batadv_hardif_put(forw_packet->if_outgoing);
 449         kfree(forw_packet);
 450 }
 451
 452 static void
 453 _batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv,
 454                                  struct batadv_forw_packet *forw_packet,
 455                                  unsigned long send_time)
 456 {
 457         /* add new packet to packet list */
 458         spin_lock_bh(&bat_priv->forw_bcast_list_lock);
 459         hlist_add_head(&forw_packet->list, &bat_priv->forw_bcast_list);
 460         spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
 461
 462         /* start timer for this packet */
 463         queue_delayed_work(batadv_event_workqueue, &forw_packet->delayed_work,
 464                            send_time);
 465 }
 466
 467 /**
 468  * batadv_add_bcast_packet_to_list - queue broadcast packet for multiple sends
 469  * @bat_priv: the bat priv with all the soft interface information
 470  * @skb: broadcast packet to add
 471  * @delay: number of jiffies to wait before sending
 472  *
 473  * add a broadcast packet to the queue and setup timers. broadcast packets
 474  * are sent multiple times to increase probability for being received.
 475  *
 476  * The skb is not consumed, so the caller should make sure that the
 477  * skb is freed.
 478  *
 479  * Return: NETDEV_TX_OK on success and NETDEV_TX_BUSY on errors.
 480  */
 481 int batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv,
 482                                     const struct sk_buff *skb,
 483                                     unsigned long delay)
 484 {
 485         struct batadv_hard_iface *primary_if = NULL;
 486         struct batadv_forw_packet *forw_packet;
 487         struct batadv_bcast_packet *bcast_packet;
 488         struct sk_buff *newskb;
 489
 490         if (!batadv_atomic_dec_not_zero(&bat_priv->bcast_queue_left)) {
 491                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 492                            "bcast packet queue full\n");
 493                 goto out;
 494         }
 495
 496         primary_if = batadv_primary_if_get_selected(bat_priv);
 497         if (!primary_if)
 498                 goto out_and_inc;
 499
 500         forw_packet = kmalloc(sizeof(*forw_packet), GFP_ATOMIC);
 501
 502         if (!forw_packet)
 503                 goto out_and_inc;
 504
 505         newskb = skb_copy(skb, GFP_ATOMIC);
 506         if (!newskb)
 507                 goto packet_free;
 508
 509         /* as we have a copy now, it is safe to decrease the TTL */
 510         bcast_packet = (struct batadv_bcast_packet *)newskb->data;
 511         bcast_packet->ttl--;
 512
 513         skb_reset_mac_header(newskb);
 514
 515         forw_packet->skb = newskb;
 516         forw_packet->if_incoming = primary_if;
 517         forw_packet->if_outgoing = NULL;
 518
 519         /* how often did we send the bcast packet ? */
 520         forw_packet->num_packets = 0;
 521
 522         INIT_DELAYED_WORK(&forw_packet->delayed_work,
 523                           batadv_send_outstanding_bcast_packet);
 524
 525         _batadv_add_bcast_packet_to_list(bat_priv, forw_packet, delay);
 526         return NETDEV_TX_OK;
 527
 528 packet_free:
 529         kfree(forw_packet);
 530 out_and_inc:
 531         atomic_inc(&bat_priv->bcast_queue_left);
 532 out:
 533         if (primary_if)
 534                 batadv_hardif_put(primary_if);
 535         return NETDEV_TX_BUSY;
 536 }
 537
 538 static void batadv_send_outstanding_bcast_packet(struct work_struct *work)
 539 {
 540         struct batadv_hard_iface *hard_iface;
 541         struct delayed_work *delayed_work;
 542         struct batadv_forw_packet *forw_packet;
 543         struct sk_buff *skb1;
 544         struct net_device *soft_iface;
 545         struct batadv_priv *bat_priv;
 546
 547         delayed_work = to_delayed_work(work);
 548         forw_packet = container_of(delayed_work, struct batadv_forw_packet,
 549                                    delayed_work);
 550         soft_iface = forw_packet->if_incoming->soft_iface;
 551         bat_priv = netdev_priv(soft_iface);
 552
 553         spin_lock_bh(&bat_priv->forw_bcast_list_lock);
 554         hlist_del(&forw_packet->list);
 555         spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
 556
 557         if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING)
 558                 goto out;
 559
 560         if (batadv_dat_drop_broadcast_packet(bat_priv, forw_packet))
 561                 goto out;
 562
 563         /* rebroadcast packet */
 564         rcu_read_lock();
 565         list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
 566                 if (hard_iface->soft_iface != soft_iface)
 567                         continue;
 568
 569                 if (forw_packet->num_packets >= hard_iface->num_bcasts)
 570                         continue;
 571
 572                 if (!kref_get_unless_zero(&hard_iface->refcount))
 573                         continue;
 574
 575                 /* send a copy of the saved skb */
 576                 skb1 = skb_clone(forw_packet->skb, GFP_ATOMIC);
 577                 if (skb1)
 578                         batadv_send_broadcast_skb(skb1, hard_iface);
 579
 580                 batadv_hardif_put(hard_iface);
 581         }
 582         rcu_read_unlock();
 583
 584         forw_packet->num_packets++;
 585
 586         /* if we still have some more bcasts to send */
 587         if (forw_packet->num_packets < BATADV_NUM_BCASTS_MAX) {
 588                 _batadv_add_bcast_packet_to_list(bat_priv, forw_packet,
 589                                                  msecs_to_jiffies(5));
 590                 return;
 591         }
 592
 593 out:
 594         batadv_forw_packet_free(forw_packet);
 595         atomic_inc(&bat_priv->bcast_queue_left);
 596 }
 597
 598 void
 599 batadv_purge_outstanding_packets(struct batadv_priv *bat_priv,
 600                                  const struct batadv_hard_iface *hard_iface)
 601 {
 602         struct batadv_forw_packet *forw_packet;
 603         struct hlist_node *safe_tmp_node;
 604         bool pending;
 605
 606         if (hard_iface)
 607                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 608                            "purge_outstanding_packets(): %s\n",
 609                            hard_iface->net_dev->name);
 610         else
 611                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 612                            "purge_outstanding_packets()\n");
 613
 614         /* free bcast list */
 615         spin_lock_bh(&bat_priv->forw_bcast_list_lock);
 616         hlist_for_each_entry_safe(forw_packet, safe_tmp_node,
 617                                   &bat_priv->forw_bcast_list, list) {
 618                 /* if purge_outstanding_packets() was called with an argument
 619                  * we delete only packets belonging to the given interface
 620                  */
 621                 if ((hard_iface) &&
 622                     (forw_packet->if_incoming != hard_iface) &&
 623                     (forw_packet->if_outgoing != hard_iface))
 624                         continue;
 625
 626                 spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
 627
 628                 /* batadv_send_outstanding_bcast_packet() will lock the list to
 629                  * delete the item from the list
 630                  */
 631                 pending = cancel_delayed_work_sync(&forw_packet->delayed_work);
 632                 spin_lock_bh(&bat_priv->forw_bcast_list_lock);
 633
 634                 if (pending) {
 635                         hlist_del(&forw_packet->list);
 636                         if (!forw_packet->own)
 637                                 atomic_inc(&bat_priv->bcast_queue_left);
 638
 639                         batadv_forw_packet_free(forw_packet);
 640                 }
 641         }
 642         spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
 643
 644         /* free batman packet list */
 645         spin_lock_bh(&bat_priv->forw_bat_list_lock);
 646         hlist_for_each_entry_safe(forw_packet, safe_tmp_node,
 647                                   &bat_priv->forw_bat_list, list) {
 648                 /* if purge_outstanding_packets() was called with an argument
 649                  * we delete only packets belonging to the given interface
 650                  */
 651                 if ((hard_iface) &&
 652                     (forw_packet->if_incoming != hard_iface) &&
 653                     (forw_packet->if_outgoing != hard_iface))
 654                         continue;
 655
 656                 spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 657
 658                 /* send_outstanding_bat_packet() will lock the list to
 659                  * delete the item from the list
 660                  */
 661                 pending = cancel_delayed_work_sync(&forw_packet->delayed_work);
 662                 spin_lock_bh(&bat_priv->forw_bat_list_lock);
 663
 664                 if (pending) {
 665                         hlist_del(&forw_packet->list);
 666                         if (!forw_packet->own)
 667                                 atomic_inc(&bat_priv->batman_queue_left);
 668
 669                         batadv_forw_packet_free(forw_packet);
 670                 }
 671         }
 672         spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 673 }