packet/af_packet.c

   1 /*
   2  * INET         An implementation of the TCP/IP protocol suite for the LINUX
   3  *              operating system.  INET is implemented using the  BSD Socket
   4  *              interface as the means of communication with the user level.
   5  *
   6  *              PACKET - implements raw packet sockets.
   7  *
   8  * Authors:     Ross Biro
   9  *              Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  10  *              Alan Cox, <gw4pts@gw4pts.ampr.org>
  11  *
  12  * Fixes:
  13  *              Alan Cox        :       verify_area() now used correctly
  14  *              Alan Cox        :       new skbuff lists, look ma no backlogs!
  15  *              Alan Cox        :       tidied skbuff lists.
  16  *              Alan Cox        :       Now uses generic datagram routines I
  17  *                                      added. Also fixed the peek/read crash
  18  *                                      from all old Linux datagram code.
  19  *              Alan Cox        :       Uses the improved datagram code.
  20  *              Alan Cox        :       Added NULL's for socket options.
  21  *              Alan Cox        :       Re-commented the code.
  22  *              Alan Cox        :       Use new kernel side addressing
  23  *              Rob Janssen     :       Correct MTU usage.
  24  *              Dave Platt      :       Counter leaks caused by incorrect
  25  *                                      interrupt locking and some slightly
  26  *                                      dubious gcc output. Can you read
  27  *                                      compiler: it said _VOLATILE_
  28  *      Richard Kooijman        :       Timestamp fixes.
  29  *              Alan Cox        :       New buffers. Use sk->mac.raw.
  30  *              Alan Cox        :       sendmsg/recvmsg support.
  31  *              Alan Cox        :       Protocol setting support
  32  *      Alexey Kuznetsov        :       Untied from IPv4 stack.
  33  *      Cyrus Durgin            :       Fixed kerneld for kmod.
  34  *      Michal Ostrowski        :       Module initialization cleanup.
  35  *         Ulises Alonso        :       Frame number limit removal and
  36  *                                      packet_set_ring memory leak.
  37  *              Eric Biederman  :       Allow for > 8 byte hardware addresses.
  38  *                                      The convention is that longer addresses
  39  *                                      will simply extend the hardware address
  40  *                                      byte arrays at the end of sockaddr_ll
  41  *                                      and packet_mreq.
  42  *              Johann Baudy    :       Added TX RING.
  43  *              Chetan Loke     :       Implemented TPACKET_V3 block abstraction
  44  *                                      layer.
  45  *                                      Copyright (C) 2011, <lokec@ccs.neu.edu>
  46  *
  47  *
  48  *              This program is free software; you can redistribute it and/or
  49  *              modify it under the terms of the GNU General Public License
  50  *              as published by the Free Software Foundation; either version
  51  *              2 of the License, or (at your option) any later version.
  52  *
  53  */
  54
  55 #include <linux/types.h>
  56 #include <linux/mm.h>
  57 #include <linux/capability.h>
  58 #include <linux/fcntl.h>
  59 #include <linux/socket.h>
  60 #include <linux/in.h>
  61 #include <linux/inet.h>
  62 #include <linux/netdevice.h>
  63 #include <linux/if_packet.h>
  64 #include <linux/wireless.h>
  65 #include <linux/kernel.h>
  66 #include <linux/kmod.h>
  67 #include <linux/slab.h>
  68 #include <linux/vmalloc.h>
  69 #include <net/net_namespace.h>
  70 #include <net/ip.h>
  71 #include <net/protocol.h>
  72 #include <linux/skbuff.h>
  73 #include <net/sock.h>
  74 #include <linux/errno.h>
  75 #include <linux/timer.h>
  76 #include <linux/uaccess.h>
  77 #include <asm/ioctls.h>
  78 #include <asm/page.h>
  79 #include <asm/cacheflush.h>
  80 #include <asm/io.h>
  81 #include <linux/proc_fs.h>
  82 #include <linux/seq_file.h>
  83 #include <linux/poll.h>
  84 #include <linux/module.h>
  85 #include <linux/init.h>
  86 #include <linux/mutex.h>
  87 #include <linux/if_vlan.h>
  88 #include <linux/virtio_net.h>
  89 #include <linux/errqueue.h>
  90 #include <linux/net_tstamp.h>
  91 #include <linux/percpu.h>
  92 #ifdef CONFIG_INET
  93 #include <net/inet_common.h>
  94 #endif
  95 #include <linux/bpf.h>
  96 #include <net/compat.h>
  97
  98 #include "internal.h"
  99
 100 /*
 101    Assumptions:
 102    - if device has no dev->hard_header routine, it adds and removes ll header
 103      inside itself. In this case ll header is invisible outside of device,
 104      but higher levels still should reserve dev->hard_header_len.
 105      Some devices are enough clever to reallocate skb, when header
 106      will not fit to reserved space (tunnel), another ones are silly
 107      (PPP).
 108    - packet socket receives packets with pulled ll header,
 109      so that SOCK_RAW should push it back.
 110
 111 On receive:
 112 -----------
 113
 114 Incoming, dev->hard_header!=NULL
 115    mac_header -> ll header
 116    data       -> data
 117
 118 Outgoing, dev->hard_header!=NULL
 119    mac_header -> ll header
 120    data       -> ll header
 121
 122 Incoming, dev->hard_header==NULL
 123    mac_header -> UNKNOWN position. It is very likely, that it points to ll
 124                  header.  PPP makes it, that is wrong, because introduce
 125                  assymetry between rx and tx paths.
 126    data       -> data
 127
 128 Outgoing, dev->hard_header==NULL
 129    mac_header -> data. ll header is still not built!
 130    data       -> data
 131
 132 Resume
 133   If dev->hard_header==NULL we are unlikely to restore sensible ll header.
 134
 135
 136 On transmit:
 137 ------------
 138
 139 dev->hard_header != NULL
 140    mac_header -> ll header
 141    data       -> ll header
 142
 143 dev->hard_header == NULL (ll header is added by device, we cannot control it)
 144    mac_header -> data
 145    data       -> data
 146
 147    We should set nh.raw on output to correct posistion,
 148    packet classifier depends on it.
 149  */
 150
 151 /* Private packet socket structures. */
 152
 153 /* identical to struct packet_mreq except it has
 154  * a longer address field.
 155  */
 156 struct packet_mreq_max {
 157         int             mr_ifindex;
 158         unsigned short  mr_type;
 159         unsigned short  mr_alen;
 160         unsigned char   mr_address[MAX_ADDR_LEN];
 161 };
 162
 163 union tpacket_uhdr {
 164         struct tpacket_hdr  *h1;
 165         struct tpacket2_hdr *h2;
 166         struct tpacket3_hdr *h3;
 167         void *raw;
 168 };
 169
 170 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
 171                 int closing, int tx_ring);
 172
 173 #define V3_ALIGNMENT    (8)
 174
 175 #define BLK_HDR_LEN     (ALIGN(sizeof(struct tpacket_block_desc), V3_ALIGNMENT))
 176
 177 #define BLK_PLUS_PRIV(sz_of_priv) \
 178         (BLK_HDR_LEN + ALIGN((sz_of_priv), V3_ALIGNMENT))
 179
 180 #define BLOCK_STATUS(x) ((x)->hdr.bh1.block_status)
 181 #define BLOCK_NUM_PKTS(x)       ((x)->hdr.bh1.num_pkts)
 182 #define BLOCK_O2FP(x)           ((x)->hdr.bh1.offset_to_first_pkt)
 183 #define BLOCK_LEN(x)            ((x)->hdr.bh1.blk_len)
 184 #define BLOCK_SNUM(x)           ((x)->hdr.bh1.seq_num)
 185 #define BLOCK_O2PRIV(x) ((x)->offset_to_priv)
 186 #define BLOCK_PRIV(x)           ((void *)((char *)(x) + BLOCK_O2PRIV(x)))
 187
 188 struct packet_sock;
 189 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
 190                        struct packet_type *pt, struct net_device *orig_dev);
 191
 192 static void *packet_previous_frame(struct packet_sock *po,
 193                 struct packet_ring_buffer *rb,
 194                 int status);
 195 static void packet_increment_head(struct packet_ring_buffer *buff);
 196 static int prb_curr_blk_in_use(struct tpacket_block_desc *);
 197 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *,
 198                         struct packet_sock *);
 199 static void prb_retire_current_block(struct tpacket_kbdq_core *,
 200                 struct packet_sock *, unsigned int status);
 201 static int prb_queue_frozen(struct tpacket_kbdq_core *);
 202 static void prb_open_block(struct tpacket_kbdq_core *,
 203                 struct tpacket_block_desc *);
 204 static void prb_retire_rx_blk_timer_expired(unsigned long);
 205 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *);
 206 static void prb_init_blk_timer(struct packet_sock *,
 207                 struct tpacket_kbdq_core *,
 208                 void (*func) (unsigned long));
 209 static void prb_fill_rxhash(struct tpacket_kbdq_core *, struct tpacket3_hdr *);
 210 static void prb_clear_rxhash(struct tpacket_kbdq_core *,
 211                 struct tpacket3_hdr *);
 212 static void prb_fill_vlan_info(struct tpacket_kbdq_core *,
 213                 struct tpacket3_hdr *);
 214 static void packet_flush_mclist(struct sock *sk);
 215 static void packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb);
 216
 217 struct packet_skb_cb {
 218         union {
 219                 struct sockaddr_pkt pkt;
 220                 union {
 221                         /* Trick: alias skb original length with
 222                          * ll.sll_family and ll.protocol in order
 223                          * to save room.
 224                          */
 225                         unsigned int origlen;
 226                         struct sockaddr_ll ll;
 227                 };
 228         } sa;
 229 };
 230
 231 #define vio_le() virtio_legacy_is_little_endian()
 232
 233 #define PACKET_SKB_CB(__skb)    ((struct packet_skb_cb *)((__skb)->cb))
 234
 235 #define GET_PBDQC_FROM_RB(x)    ((struct tpacket_kbdq_core *)(&(x)->prb_bdqc))
 236 #define GET_PBLOCK_DESC(x, bid) \
 237         ((struct tpacket_block_desc *)((x)->pkbdq[(bid)].buffer))
 238 #define GET_CURR_PBLOCK_DESC_FROM_CORE(x)       \
 239         ((struct tpacket_block_desc *)((x)->pkbdq[(x)->kactive_blk_num].buffer))
 240 #define GET_NEXT_PRB_BLK_NUM(x) \
 241         (((x)->kactive_blk_num < ((x)->knum_blocks-1)) ? \
 242         ((x)->kactive_blk_num+1) : 0)
 243
 244 static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
 245 static void __fanout_link(struct sock *sk, struct packet_sock *po);
 246
 247 static int packet_direct_xmit(struct sk_buff *skb)
 248 {
 249         struct net_device *dev = skb->dev;
 250         struct sk_buff *orig_skb = skb;
 251         struct netdev_queue *txq;
 252         int ret = NETDEV_TX_BUSY;
 253
 254         if (unlikely(!netif_running(dev) ||
 255                      !netif_carrier_ok(dev)))
 256                 goto drop;
 257
 258         skb = validate_xmit_skb_list(skb, dev);
 259         if (skb != orig_skb)
 260                 goto drop;
 261
 262         packet_pick_tx_queue(dev, skb);
 263         txq = skb_get_tx_queue(dev, skb);
 264
 265         local_bh_disable();
 266
 267         HARD_TX_LOCK(dev, txq, smp_processor_id());
 268         if (!netif_xmit_frozen_or_drv_stopped(txq))
 269                 ret = netdev_start_xmit(skb, dev, txq, false);
 270         HARD_TX_UNLOCK(dev, txq);
 271
 272         local_bh_enable();
 273
 274         if (!dev_xmit_complete(ret))
 275                 kfree_skb(skb);
 276
 277         return ret;
 278 drop:
 279         atomic_long_inc(&dev->tx_dropped);
 280         kfree_skb_list(skb);
 281         return NET_XMIT_DROP;
 282 }
 283
 284 static struct net_device *packet_cached_dev_get(struct packet_sock *po)
 285 {
 286         struct net_device *dev;
 287
 288         rcu_read_lock();
 289         dev = rcu_dereference(po->cached_dev);
 290         if (likely(dev))
 291                 dev_hold(dev);
 292         rcu_read_unlock();
 293
 294         return dev;
 295 }
 296
 297 static void packet_cached_dev_assign(struct packet_sock *po,
 298                                      struct net_device *dev)
 299 {
 300         rcu_assign_pointer(po->cached_dev, dev);
 301 }
 302
 303 static void packet_cached_dev_reset(struct packet_sock *po)
 304 {
 305         RCU_INIT_POINTER(po->cached_dev, NULL);
 306 }
 307
 308 static bool packet_use_direct_xmit(const struct packet_sock *po)
 309 {
 310         return po->xmit == packet_direct_xmit;
 311 }
 312
 313 static u16 __packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
 314 {
 315         return (u16) raw_smp_processor_id() % dev->real_num_tx_queues;
 316 }
 317
 318 static void packet_pick_tx_queue(struct net_device *dev, struct sk_buff *skb)
 319 {
 320         const struct net_device_ops *ops = dev->netdev_ops;
 321         u16 queue_index;
 322
 323         if (ops->ndo_select_queue) {
 324                 queue_index = ops->ndo_select_queue(dev, skb, NULL,
 325                                                     __packet_pick_tx_queue);
 326                 queue_index = netdev_cap_txqueue(dev, queue_index);
 327         } else {
 328                 queue_index = __packet_pick_tx_queue(dev, skb);
 329         }
 330
 331         skb_set_queue_mapping(skb, queue_index);
 332 }
 333
 334 /* __register_prot_hook must be invoked through register_prot_hook
 335  * or from a context in which asynchronous accesses to the packet
 336  * socket is not possible (packet_create()).
 337  */
 338 static void __register_prot_hook(struct sock *sk)
 339 {
 340         struct packet_sock *po = pkt_sk(sk);
 341
 342         if (!po->running) {
 343                 if (po->fanout)
 344                         __fanout_link(sk, po);
 345                 else
 346                         dev_add_pack(&po->prot_hook);
 347
 348                 sock_hold(sk);
 349                 po->running = 1;
 350         }
 351 }
 352
 353 static void register_prot_hook(struct sock *sk)
 354 {
 355         lockdep_assert_held_once(&pkt_sk(sk)->bind_lock);
 356         __register_prot_hook(sk);
 357 }
 358
 359 /* If the sync parameter is true, we will temporarily drop
 360  * the po->bind_lock and do a synchronize_net to make sure no
 361  * asynchronous packet processing paths still refer to the elements
 362  * of po->prot_hook.  If the sync parameter is false, it is the
 363  * callers responsibility to take care of this.
 364  */
 365 static void __unregister_prot_hook(struct sock *sk, bool sync)
 366 {
 367         struct packet_sock *po = pkt_sk(sk);
 368
 369         lockdep_assert_held_once(&po->bind_lock);
 370
 371         po->running = 0;
 372
 373         if (po->fanout)
 374                 __fanout_unlink(sk, po);
 375         else
 376                 __dev_remove_pack(&po->prot_hook);
 377
 378         __sock_put(sk);
 379
 380         if (sync) {
 381                 spin_unlock(&po->bind_lock);
 382                 synchronize_net();
 383                 spin_lock(&po->bind_lock);
 384         }
 385 }
 386
 387 static void unregister_prot_hook(struct sock *sk, bool sync)
 388 {
 389         struct packet_sock *po = pkt_sk(sk);
 390
 391         if (po->running)
 392                 __unregister_prot_hook(sk, sync);
 393 }
 394
 395 static inline struct page * __pure pgv_to_page(void *addr)
 396 {
 397         if (is_vmalloc_addr(addr))
 398                 return vmalloc_to_page(addr);
 399         return virt_to_page(addr);
 400 }
 401
 402 static void __packet_set_status(struct packet_sock *po, void *frame, int status)
 403 {
 404         union tpacket_uhdr h;
 405
 406         h.raw = frame;
 407         switch (po->tp_version) {
 408         case TPACKET_V1:
 409                 h.h1->tp_status = status;
 410                 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
 411                 break;
 412         case TPACKET_V2:
 413                 h.h2->tp_status = status;
 414                 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
 415                 break;
 416         case TPACKET_V3:
 417                 h.h3->tp_status = status;
 418                 flush_dcache_page(pgv_to_page(&h.h3->tp_status));
 419                 break;
 420         default:
 421                 WARN(1, "TPACKET version not supported.\n");
 422                 BUG();
 423         }
 424
 425         smp_wmb();
 426 }
 427
 428 static int __packet_get_status(struct packet_sock *po, void *frame)
 429 {
 430         union tpacket_uhdr h;
 431
 432         smp_rmb();
 433
 434         h.raw = frame;
 435         switch (po->tp_version) {
 436         case TPACKET_V1:
 437                 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
 438                 return h.h1->tp_status;
 439         case TPACKET_V2:
 440                 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
 441                 return h.h2->tp_status;
 442         case TPACKET_V3:
 443                 flush_dcache_page(pgv_to_page(&h.h3->tp_status));
 444                 return h.h3->tp_status;
 445         default:
 446                 WARN(1, "TPACKET version not supported.\n");
 447                 BUG();
 448                 return 0;
 449         }
 450 }
 451
 452 static __u32 tpacket_get_timestamp(struct sk_buff *skb, struct timespec *ts,
 453                                    unsigned int flags)
 454 {
 455         struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
 456
 457         if (shhwtstamps &&
 458             (flags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
 459             ktime_to_timespec_cond(shhwtstamps->hwtstamp, ts))
 460                 return TP_STATUS_TS_RAW_HARDWARE;
 461
 462         if (ktime_to_timespec_cond(skb->tstamp, ts))
 463                 return TP_STATUS_TS_SOFTWARE;
 464
 465         return 0;
 466 }
 467
 468 static __u32 __packet_set_timestamp(struct packet_sock *po, void *frame,
 469                                     struct sk_buff *skb)
 470 {
 471         union tpacket_uhdr h;
 472         struct timespec ts;
 473         __u32 ts_status;
 474
 475         if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
 476                 return 0;
 477
 478         h.raw = frame;
 479         switch (po->tp_version) {
 480         case TPACKET_V1:
 481                 h.h1->tp_sec = ts.tv_sec;
 482                 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
 483                 break;
 484         case TPACKET_V2:
 485                 h.h2->tp_sec = ts.tv_sec;
 486                 h.h2->tp_nsec = ts.tv_nsec;
 487                 break;
 488         case TPACKET_V3:
 489                 h.h3->tp_sec = ts.tv_sec;
 490                 h.h3->tp_nsec = ts.tv_nsec;
 491                 break;
 492         default:
 493                 WARN(1, "TPACKET version not supported.\n");
 494                 BUG();
 495         }
 496
 497         /* one flush is safe, as both fields always lie on the same cacheline */
 498         flush_dcache_page(pgv_to_page(&h.h1->tp_sec));
 499         smp_wmb();
 500
 501         return ts_status;
 502 }
 503
 504 static void *packet_lookup_frame(struct packet_sock *po,
 505                 struct packet_ring_buffer *rb,
 506                 unsigned int position,
 507                 int status)
 508 {
 509         unsigned int pg_vec_pos, frame_offset;
 510         union tpacket_uhdr h;
 511
 512         pg_vec_pos = position / rb->frames_per_block;
 513         frame_offset = position % rb->frames_per_block;
 514
 515         h.raw = rb->pg_vec[pg_vec_pos].buffer +
 516                 (frame_offset * rb->frame_size);
 517
 518         if (status != __packet_get_status(po, h.raw))
 519                 return NULL;
 520
 521         return h.raw;
 522 }
 523
 524 static void *packet_current_frame(struct packet_sock *po,
 525                 struct packet_ring_buffer *rb,
 526                 int status)
 527 {
 528         return packet_lookup_frame(po, rb, rb->head, status);
 529 }
 530
 531 static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc)
 532 {
 533         del_timer_sync(&pkc->retire_blk_timer);
 534 }
 535
 536 static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
 537                 struct sk_buff_head *rb_queue)
 538 {
 539         struct tpacket_kbdq_core *pkc;
 540
 541         pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
 542
 543         spin_lock_bh(&rb_queue->lock);
 544         pkc->delete_blk_timer = 1;
 545         spin_unlock_bh(&rb_queue->lock);
 546
 547         prb_del_retire_blk_timer(pkc);
 548 }
 549
 550 static void prb_init_blk_timer(struct packet_sock *po,
 551                 struct tpacket_kbdq_core *pkc,
 552                 void (*func) (unsigned long))
 553 {
 554         init_timer(&pkc->retire_blk_timer);
 555         pkc->retire_blk_timer.data = (long)po;
 556         pkc->retire_blk_timer.function = func;
 557         pkc->retire_blk_timer.expires = jiffies;
 558 }
 559
 560 static void prb_setup_retire_blk_timer(struct packet_sock *po)
 561 {
 562         struct tpacket_kbdq_core *pkc;
 563
 564         pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
 565         prb_init_blk_timer(po, pkc, prb_retire_rx_blk_timer_expired);
 566 }
 567
 568 static int prb_calc_retire_blk_tmo(struct packet_sock *po,
 569                                 int blk_size_in_bytes)
 570 {
 571         struct net_device *dev;
 572         unsigned int mbits = 0, msec = 0, div = 0, tmo = 0;
 573         struct ethtool_link_ksettings ecmd;
 574         int err;
 575
 576         rtnl_lock();
 577         dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
 578         if (unlikely(!dev)) {
 579                 rtnl_unlock();
 580                 return DEFAULT_PRB_RETIRE_TOV;
 581         }
 582         err = __ethtool_get_link_ksettings(dev, &ecmd);
 583         rtnl_unlock();
 584         if (!err) {
 585                 /*
 586                  * If the link speed is so slow you don't really
 587                  * need to worry about perf anyways
 588                  */
 589                 if (ecmd.base.speed < SPEED_1000 ||
 590                     ecmd.base.speed == SPEED_UNKNOWN) {
 591                         return DEFAULT_PRB_RETIRE_TOV;
 592                 } else {
 593                         msec = 1;
 594                         div = ecmd.base.speed / 1000;
 595                 }
 596         } else
 597                 return DEFAULT_PRB_RETIRE_TOV;
 598
 599         mbits = (blk_size_in_bytes * 8) / (1024 * 1024);
 600
 601         if (div)
 602                 mbits /= div;
 603
 604         tmo = mbits * msec;
 605
 606         if (div)
 607                 return tmo+1;
 608         return tmo;
 609 }
 610
 611 static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
 612                         union tpacket_req_u *req_u)
 613 {
 614         p1->feature_req_word = req_u->req3.tp_feature_req_word;
 615 }
 616
 617 static void init_prb_bdqc(struct packet_sock *po,
 618                         struct packet_ring_buffer *rb,
 619                         struct pgv *pg_vec,
 620                         union tpacket_req_u *req_u)
 621 {
 622         struct tpacket_kbdq_core *p1 = GET_PBDQC_FROM_RB(rb);
 623         struct tpacket_block_desc *pbd;
 624
 625         memset(p1, 0x0, sizeof(*p1));
 626
 627         p1->knxt_seq_num = 1;
 628         p1->pkbdq = pg_vec;
 629         pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
 630         p1->pkblk_start = pg_vec[0].buffer;
 631         p1->kblk_size = req_u->req3.tp_block_size;
 632         p1->knum_blocks = req_u->req3.tp_block_nr;
 633         p1->hdrlen = po->tp_hdrlen;
 634         p1->version = po->tp_version;
 635         p1->last_kactive_blk_num = 0;
 636         po->stats.stats3.tp_freeze_q_cnt = 0;
 637         if (req_u->req3.tp_retire_blk_tov)
 638                 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
 639         else
 640                 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
 641                                                 req_u->req3.tp_block_size);
 642         p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
 643         p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;
 644
 645         p1->max_frame_len = p1->kblk_size - BLK_PLUS_PRIV(p1->blk_sizeof_priv);
 646         prb_init_ft_ops(p1, req_u);
 647         prb_setup_retire_blk_timer(po);
 648         prb_open_block(p1, pbd);
 649 }
 650
 651 /*  Do NOT update the last_blk_num first.
 652  *  Assumes sk_buff_head lock is held.
 653  */
 654 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
 655 {
 656         mod_timer(&pkc->retire_blk_timer,
 657                         jiffies + pkc->tov_in_jiffies);
 658         pkc->last_kactive_blk_num = pkc->kactive_blk_num;
 659 }
 660
 661 /*
 662  * Timer logic:
 663  * 1) We refresh the timer only when we open a block.
 664  *    By doing this we don't waste cycles refreshing the timer
 665  *        on packet-by-packet basis.
 666  *
 667  * With a 1MB block-size, on a 1Gbps line, it will take
 668  * i) ~8 ms to fill a block + ii) memcpy etc.
 669  * In this cut we are not accounting for the memcpy time.
 670  *
 671  * So, if the user sets the 'tmo' to 10ms then the timer
 672  * will never fire while the block is still getting filled
 673  * (which is what we want). However, the user could choose
 674  * to close a block early and that's fine.
 675  *
 676  * But when the timer does fire, we check whether or not to refresh it.
 677  * Since the tmo granularity is in msecs, it is not too expensive
 678  * to refresh the timer, lets say every '8' msecs.
 679  * Either the user can set the 'tmo' or we can derive it based on
 680  * a) line-speed and b) block-size.
 681  * prb_calc_retire_blk_tmo() calculates the tmo.
 682  *
 683  */
 684 static void prb_retire_rx_blk_timer_expired(unsigned long data)
 685 {
 686         struct packet_sock *po = (struct packet_sock *)data;
 687         struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
 688         unsigned int frozen;
 689         struct tpacket_block_desc *pbd;
 690
 691         spin_lock(&po->sk.sk_receive_queue.lock);
 692
 693         frozen = prb_queue_frozen(pkc);
 694         pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
 695
 696         if (unlikely(pkc->delete_blk_timer))
 697                 goto out;
 698
 699         /* We only need to plug the race when the block is partially filled.
 700          * tpacket_rcv:
 701          *              lock(); increment BLOCK_NUM_PKTS; unlock()
 702          *              copy_bits() is in progress ...
 703          *              timer fires on other cpu:
 704          *              we can't retire the current block because copy_bits
 705          *              is in progress.
 706          *
 707          */
 708         if (BLOCK_NUM_PKTS(pbd)) {
 709                 while (atomic_read(&pkc->blk_fill_in_prog)) {
 710                         /* Waiting for skb_copy_bits to finish... */
 711                         cpu_relax();
 712                 }
 713         }
 714
 715         if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
 716                 if (!frozen) {
 717                         if (!BLOCK_NUM_PKTS(pbd)) {
 718                                 /* An empty block. Just refresh the timer. */
 719                                 goto refresh_timer;
 720                         }
 721                         prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
 722                         if (!prb_dispatch_next_block(pkc, po))
 723                                 goto refresh_timer;
 724                         else
 725                                 goto out;
 726                 } else {
 727                         /* Case 1. Queue was frozen because user-space was
 728                          *         lagging behind.
 729                          */
 730                         if (prb_curr_blk_in_use(pbd)) {
 731                                 /*
 732                                  * Ok, user-space is still behind.
 733                                  * So just refresh the timer.
 734                                  */
 735                                 goto refresh_timer;
 736                         } else {
 737                                /* Case 2. queue was frozen,user-space caught up,
 738                                 * now the link went idle && the timer fired.
 739                                 * We don't have a block to close.So we open this
 740                                 * block and restart the timer.
 741                                 * opening a block thaws the queue,restarts timer
 742                                 * Thawing/timer-refresh is a side effect.
 743                                 */
 744                                 prb_open_block(pkc, pbd);
 745                                 goto out;
 746                         }
 747                 }
 748         }
 749
 750 refresh_timer:
 751         _prb_refresh_rx_retire_blk_timer(pkc);
 752
 753 out:
 754         spin_unlock(&po->sk.sk_receive_queue.lock);
 755 }
 756
 757 static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
 758                 struct tpacket_block_desc *pbd1, __u32 status)
 759 {
 760         /* Flush everything minus the block header */
 761
 762 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
 763         u8 *start, *end;
 764
 765         start = (u8 *)pbd1;
 766
 767         /* Skip the block header(we know header WILL fit in 4K) */
 768         start += PAGE_SIZE;
 769
 770         end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end);
 771         for (; start < end; start += PAGE_SIZE)
 772                 flush_dcache_page(pgv_to_page(start));
 773
 774         smp_wmb();
 775 #endif
 776
 777         /* Now update the block status. */
 778
 779         BLOCK_STATUS(pbd1) = status;
 780
 781         /* Flush the block header */
 782
 783 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
 784         start = (u8 *)pbd1;
 785         flush_dcache_page(pgv_to_page(start));
 786
 787         smp_wmb();
 788 #endif
 789 }
 790
 791 /*
 792  * Side effect:
 793  *
 794  * 1) flush the block
 795  * 2) Increment active_blk_num
 796  *
 797  * Note:We DONT refresh the timer on purpose.
 798  *      Because almost always the next block will be opened.
 799  */
 800 static void prb_close_block(struct tpacket_kbdq_core *pkc1,
 801                 struct tpacket_block_desc *pbd1,
 802                 struct packet_sock *po, unsigned int stat)
 803 {
 804         __u32 status = TP_STATUS_USER | stat;
 805
 806         struct tpacket3_hdr *last_pkt;
 807         struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
 808         struct sock *sk = &po->sk;
 809
 810         if (po->stats.stats3.tp_drops)
 811                 status |= TP_STATUS_LOSING;
 812
 813         last_pkt = (struct tpacket3_hdr *)pkc1->prev;
 814         last_pkt->tp_next_offset = 0;
 815
 816         /* Get the ts of the last pkt */
 817         if (BLOCK_NUM_PKTS(pbd1)) {
 818                 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
 819                 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec;
 820         } else {
 821                 /* Ok, we tmo'd - so get the current time.
 822                  *
 823                  * It shouldn't really happen as we don't close empty
 824                  * blocks. See prb_retire_rx_blk_timer_expired().
 825                  */
 826                 struct timespec ts;
 827                 getnstimeofday(&ts);
 828                 h1->ts_last_pkt.ts_sec = ts.tv_sec;
 829                 h1->ts_last_pkt.ts_nsec = ts.tv_nsec;
 830         }
 831
 832         smp_wmb();
 833
 834         /* Flush the block */
 835         prb_flush_block(pkc1, pbd1, status);
 836
 837         sk->sk_data_ready(sk);
 838
 839         pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
 840 }
 841
 842 static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
 843 {
 844         pkc->reset_pending_on_curr_blk = 0;
 845 }
 846
 847 /*
 848  * Side effect of opening a block:
 849  *
 850  * 1) prb_queue is thawed.
 851  * 2) retire_blk_timer is refreshed.
 852  *
 853  */
 854 static void prb_open_block(struct tpacket_kbdq_core *pkc1,
 855         struct tpacket_block_desc *pbd1)
 856 {
 857         struct timespec ts;
 858         struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
 859
 860         smp_rmb();
 861
 862         /* We could have just memset this but we will lose the
 863          * flexibility of making the priv area sticky
 864          */
 865
 866         BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
 867         BLOCK_NUM_PKTS(pbd1) = 0;
 868         BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
 869
 870         getnstimeofday(&ts);
 871
 872         h1->ts_first_pkt.ts_sec = ts.tv_sec;
 873         h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
 874
 875         pkc1->pkblk_start = (char *)pbd1;
 876         pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
 877
 878         BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
 879         BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;
 880
 881         pbd1->version = pkc1->version;
 882         pkc1->prev = pkc1->nxt_offset;
 883         pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
 884
 885         prb_thaw_queue(pkc1);
 886         _prb_refresh_rx_retire_blk_timer(pkc1);
 887
 888         smp_wmb();
 889 }
 890
 891 /*
 892  * Queue freeze logic:
 893  * 1) Assume tp_block_nr = 8 blocks.
 894  * 2) At time 't0', user opens Rx ring.
 895  * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
 896  * 4) user-space is either sleeping or processing block '0'.
 897  * 5) tpacket_rcv is currently filling block '7', since there is no space left,
 898  *    it will close block-7,loop around and try to fill block '0'.
 899  *    call-flow:
 900  *    __packet_lookup_frame_in_block
 901  *      prb_retire_current_block()
 902  *      prb_dispatch_next_block()
 903  *        |->(BLOCK_STATUS == USER) evaluates to true
 904  *    5.1) Since block-0 is currently in-use, we just freeze the queue.
 905  * 6) Now there are two cases:
 906  *    6.1) Link goes idle right after the queue is frozen.
 907  *         But remember, the last open_block() refreshed the timer.
 908  *         When this timer expires,it will refresh itself so that we can
 909  *         re-open block-0 in near future.
 910  *    6.2) Link is busy and keeps on receiving packets. This is a simple
 911  *         case and __packet_lookup_frame_in_block will check if block-0
 912  *         is free and can now be re-used.
 913  */
 914 static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
 915                                   struct packet_sock *po)
 916 {
 917         pkc->reset_pending_on_curr_blk = 1;
 918         po->stats.stats3.tp_freeze_q_cnt++;
 919 }
 920
 921 #define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT))
 922
 923 /*
 924  * If the next block is free then we will dispatch it
 925  * and return a good offset.
 926  * Else, we will freeze the queue.
 927  * So, caller must check the return value.
 928  */
 929 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
 930                 struct packet_sock *po)
 931 {
 932         struct tpacket_block_desc *pbd;
 933
 934         smp_rmb();
 935
 936         /* 1. Get current block num */
 937         pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
 938
 939         /* 2. If this block is currently in_use then freeze the queue */
 940         if (TP_STATUS_USER & BLOCK_STATUS(pbd)) {
 941                 prb_freeze_queue(pkc, po);
 942                 return NULL;
 943         }
 944
 945         /*
 946          * 3.
 947          * open this block and return the offset where the first packet
 948          * needs to get stored.
 949          */
 950         prb_open_block(pkc, pbd);
 951         return (void *)pkc->nxt_offset;
 952 }
 953
 954 static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
 955                 struct packet_sock *po, unsigned int status)
 956 {
 957         struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
 958
 959         /* retire/close the current block */
 960         if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) {
 961                 /*
 962                  * Plug the case where copy_bits() is in progress on
 963                  * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't
 964                  * have space to copy the pkt in the current block and
 965                  * called prb_retire_current_block()
 966                  *
 967                  * We don't need to worry about the TMO case because
 968                  * the timer-handler already handled this case.
 969                  */
 970                 if (!(status & TP_STATUS_BLK_TMO)) {
 971                         while (atomic_read(&pkc->blk_fill_in_prog)) {
 972                                 /* Waiting for skb_copy_bits to finish... */
 973                                 cpu_relax();
 974                         }
 975                 }
 976                 prb_close_block(pkc, pbd, po, status);
 977                 return;
 978         }
 979 }
 980
 981 static int prb_curr_blk_in_use(struct tpacket_block_desc *pbd)
 982 {
 983         return TP_STATUS_USER & BLOCK_STATUS(pbd);
 984 }
 985
 986 static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
 987 {
 988         return pkc->reset_pending_on_curr_blk;
 989 }
 990
 991 static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
 992         __releases(&pkc->blk_fill_in_prog_lock)
 993 {
 994         struct tpacket_kbdq_core *pkc  = GET_PBDQC_FROM_RB(rb);
 995         atomic_dec(&pkc->blk_fill_in_prog);
 996 }
 997
 998 static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
 999                         struct tpacket3_hdr *ppd)
1000 {
1001         ppd->hv1.tp_rxhash = skb_get_hash(pkc->skb);
1002 }
1003
1004 static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
1005                         struct tpacket3_hdr *ppd)
1006 {
1007         ppd->hv1.tp_rxhash = 0;
1008 }
1009
1010 static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
1011                         struct tpacket3_hdr *ppd)
1012 {
1013         if (skb_vlan_tag_present(pkc->skb)) {
1014                 ppd->hv1.tp_vlan_tci = skb_vlan_tag_get(pkc->skb);
1015                 ppd->hv1.tp_vlan_tpid = ntohs(pkc->skb->vlan_proto);
1016                 ppd->tp_status = TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
1017         } else {
1018                 ppd->hv1.tp_vlan_tci = 0;
1019                 ppd->hv1.tp_vlan_tpid = 0;
1020                 ppd->tp_status = TP_STATUS_AVAILABLE;
1021         }
1022 }
1023
1024 static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
1025                         struct tpacket3_hdr *ppd)
1026 {
1027         ppd->hv1.tp_padding = 0;
1028         prb_fill_vlan_info(pkc, ppd);
1029
1030         if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH)
1031                 prb_fill_rxhash(pkc, ppd);
1032         else
1033                 prb_clear_rxhash(pkc, ppd);
1034 }
1035
1036 static void prb_fill_curr_block(char *curr,
1037                                 struct tpacket_kbdq_core *pkc,
1038                                 struct tpacket_block_desc *pbd,
1039                                 unsigned int len)
1040         __acquires(&pkc->blk_fill_in_prog_lock)
1041 {
1042         struct tpacket3_hdr *ppd;
1043
1044         ppd  = (struct tpacket3_hdr *)curr;
1045         ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len);
1046         pkc->prev = curr;
1047         pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len);
1048         BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len);
1049         BLOCK_NUM_PKTS(pbd) += 1;
1050         atomic_inc(&pkc->blk_fill_in_prog);
1051         prb_run_all_ft_ops(pkc, ppd);
1052 }
1053
1054 /* Assumes caller has the sk->rx_queue.lock */
1055 static void *__packet_lookup_frame_in_block(struct packet_sock *po,
1056                                             struct sk_buff *skb,
1057                                                 int status,
1058                                             unsigned int len
1059                                             )
1060 {
1061         struct tpacket_kbdq_core *pkc;
1062         struct tpacket_block_desc *pbd;
1063         char *curr, *end;
1064
1065         pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
1066         pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1067
1068         /* Queue is frozen when user space is lagging behind */
1069         if (prb_queue_frozen(pkc)) {
1070                 /*
1071                  * Check if that last block which caused the queue to freeze,
1072                  * is still in_use by user-space.
1073                  */
1074                 if (prb_curr_blk_in_use(pbd)) {
1075                         /* Can't record this packet */
1076                         return NULL;
1077                 } else {
1078                         /*
1079                          * Ok, the block was released by user-space.
1080                          * Now let's open that block.
1081                          * opening a block also thaws the queue.
1082                          * Thawing is a side effect.
1083                          */
1084                         prb_open_block(pkc, pbd);
1085                 }
1086         }
1087
1088         smp_mb();
1089         curr = pkc->nxt_offset;
1090         pkc->skb = skb;
1091         end = (char *)pbd + pkc->kblk_size;
1092
1093         /* first try the current block */
1094         if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) {
1095                 prb_fill_curr_block(curr, pkc, pbd, len);
1096                 return (void *)curr;
1097         }
1098
1099         /* Ok, close the current block */
1100         prb_retire_current_block(pkc, po, 0);
1101
1102         /* Now, try to dispatch the next block */
1103         curr = (char *)prb_dispatch_next_block(pkc, po);
1104         if (curr) {
1105                 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1106                 prb_fill_curr_block(curr, pkc, pbd, len);
1107                 return (void *)curr;
1108         }
1109
1110         /*
1111          * No free blocks are available.user_space hasn't caught up yet.
1112          * Queue was just frozen and now this packet will get dropped.
1113          */
1114         return NULL;
1115 }
1116
1117 static void *packet_current_rx_frame(struct packet_sock *po,
1118                                             struct sk_buff *skb,
1119                                             int status, unsigned int len)
1120 {
1121         char *curr = NULL;
1122         switch (po->tp_version) {
1123         case TPACKET_V1:
1124         case TPACKET_V2:
1125                 curr = packet_lookup_frame(po, &po->rx_ring,
1126                                         po->rx_ring.head, status);
1127                 return curr;
1128         case TPACKET_V3:
1129                 return __packet_lookup_frame_in_block(po, skb, status, len);
1130         default:
1131                 WARN(1, "TPACKET version not supported\n");
1132                 BUG();
1133                 return NULL;
1134         }
1135 }
1136
1137 static void *prb_lookup_block(struct packet_sock *po,
1138                                      struct packet_ring_buffer *rb,
1139                                      unsigned int idx,
1140                                      int status)
1141 {
1142         struct tpacket_kbdq_core *pkc  = GET_PBDQC_FROM_RB(rb);
1143         struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx);
1144
1145         if (status != BLOCK_STATUS(pbd))
1146                 return NULL;
1147         return pbd;
1148 }
1149
1150 static int prb_previous_blk_num(struct packet_ring_buffer *rb)
1151 {
1152         unsigned int prev;
1153         if (rb->prb_bdqc.kactive_blk_num)
1154                 prev = rb->prb_bdqc.kactive_blk_num-1;
1155         else
1156                 prev = rb->prb_bdqc.knum_blocks-1;
1157         return prev;
1158 }
1159
1160 /* Assumes caller has held the rx_queue.lock */
1161 static void *__prb_previous_block(struct packet_sock *po,
1162                                          struct packet_ring_buffer *rb,
1163                                          int status)
1164 {
1165         unsigned int previous = prb_previous_blk_num(rb);
1166         return prb_lookup_block(po, rb, previous, status);
1167 }
1168
1169 static void *packet_previous_rx_frame(struct packet_sock *po,
1170                                              struct packet_ring_buffer *rb,
1171                                              int status)
1172 {
1173         if (po->tp_version <= TPACKET_V2)
1174                 return packet_previous_frame(po, rb, status);
1175
1176         return __prb_previous_block(po, rb, status);
1177 }
1178
1179 static void packet_increment_rx_head(struct packet_sock *po,
1180                                             struct packet_ring_buffer *rb)
1181 {
1182         switch (po->tp_version) {
1183         case TPACKET_V1:
1184         case TPACKET_V2:
1185                 return packet_increment_head(rb);
1186         case TPACKET_V3:
1187         default:
1188                 WARN(1, "TPACKET version not supported.\n");
1189                 BUG();
1190                 return;
1191         }
1192 }
1193
1194 static void *packet_previous_frame(struct packet_sock *po,
1195                 struct packet_ring_buffer *rb,
1196                 int status)
1197 {
1198         unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
1199         return packet_lookup_frame(po, rb, previous, status);
1200 }
1201
1202 static void packet_increment_head(struct packet_ring_buffer *buff)
1203 {
1204         buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
1205 }
1206
1207 static void packet_inc_pending(struct packet_ring_buffer *rb)
1208 {
1209         this_cpu_inc(*rb->pending_refcnt);
1210 }
1211
1212 static void packet_dec_pending(struct packet_ring_buffer *rb)
1213 {
1214         this_cpu_dec(*rb->pending_refcnt);
1215 }
1216
1217 static unsigned int packet_read_pending(const struct packet_ring_buffer *rb)
1218 {
1219         unsigned int refcnt = 0;
1220         int cpu;
1221
1222         /* We don't use pending refcount in rx_ring. */
1223         if (rb->pending_refcnt == NULL)
1224                 return 0;
1225
1226         for_each_possible_cpu(cpu)
1227                 refcnt += *per_cpu_ptr(rb->pending_refcnt, cpu);
1228
1229         return refcnt;
1230 }
1231
1232 static int packet_alloc_pending(struct packet_sock *po)
1233 {
1234         po->rx_ring.pending_refcnt = NULL;
1235
1236         po->tx_ring.pending_refcnt = alloc_percpu(unsigned int);
1237         if (unlikely(po->tx_ring.pending_refcnt == NULL))
1238                 return -ENOBUFS;
1239
1240         return 0;
1241 }
1242
1243 static void packet_free_pending(struct packet_sock *po)
1244 {
1245         free_percpu(po->tx_ring.pending_refcnt);
1246 }
1247
1248 #define ROOM_POW_OFF    2
1249 #define ROOM_NONE       0x0
1250 #define ROOM_LOW        0x1
1251 #define ROOM_NORMAL     0x2
1252
1253 static bool __tpacket_has_room(struct packet_sock *po, int pow_off)
1254 {
1255         int idx, len;
1256
1257         len = po->rx_ring.frame_max + 1;
1258         idx = po->rx_ring.head;
1259         if (pow_off)
1260                 idx += len >> pow_off;
1261         if (idx >= len)
1262                 idx -= len;
1263         return packet_lookup_frame(po, &po->rx_ring, idx, TP_STATUS_KERNEL);
1264 }
1265
1266 static bool __tpacket_v3_has_room(struct packet_sock *po, int pow_off)
1267 {
1268         int idx, len;
1269
1270         len = po->rx_ring.prb_bdqc.knum_blocks;
1271         idx = po->rx_ring.prb_bdqc.kactive_blk_num;
1272         if (pow_off)
1273                 idx += len >> pow_off;
1274         if (idx >= len)
1275                 idx -= len;
1276         return prb_lookup_block(po, &po->rx_ring, idx, TP_STATUS_KERNEL);
1277 }
1278
1279 static int __packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1280 {
1281         struct sock *sk = &po->sk;
1282         int ret = ROOM_NONE;
1283
1284         if (po->prot_hook.func != tpacket_rcv) {
1285                 int avail = sk->sk_rcvbuf - atomic_read(&sk->sk_rmem_alloc)
1286                                           - (skb ? skb->truesize : 0);
1287                 if (avail > (sk->sk_rcvbuf >> ROOM_POW_OFF))
1288                         return ROOM_NORMAL;
1289                 else if (avail > 0)
1290                         return ROOM_LOW;
1291                 else
1292                         return ROOM_NONE;
1293         }
1294
1295         if (po->tp_version == TPACKET_V3) {
1296                 if (__tpacket_v3_has_room(po, ROOM_POW_OFF))
1297                         ret = ROOM_NORMAL;
1298                 else if (__tpacket_v3_has_room(po, 0))
1299                         ret = ROOM_LOW;
1300         } else {
1301                 if (__tpacket_has_room(po, ROOM_POW_OFF))
1302                         ret = ROOM_NORMAL;
1303                 else if (__tpacket_has_room(po, 0))
1304                         ret = ROOM_LOW;
1305         }
1306
1307         return ret;
1308 }
1309
1310 static int packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1311 {
1312         int ret;
1313         bool has_room;
1314
1315         spin_lock_bh(&po->sk.sk_receive_queue.lock);
1316         ret = __packet_rcv_has_room(po, skb);
1317         has_room = ret == ROOM_NORMAL;
1318         if (po->pressure == has_room)
1319                 po->pressure = !has_room;
1320         spin_unlock_bh(&po->sk.sk_receive_queue.lock);
1321
1322         return ret;
1323 }
1324
1325 static void packet_sock_destruct(struct sock *sk)
1326 {
1327         skb_queue_purge(&sk->sk_error_queue);
1328
1329         WARN_ON(atomic_read(&sk->sk_rmem_alloc));
1330         WARN_ON(refcount_read(&sk->sk_wmem_alloc));
1331
1332         if (!sock_flag(sk, SOCK_DEAD)) {
1333                 pr_err("Attempt to release alive packet socket: %p\n", sk);
1334                 return;
1335         }
1336
1337         sk_refcnt_debug_dec(sk);
1338 }
1339
1340 static bool fanout_flow_is_huge(struct packet_sock *po, struct sk_buff *skb)
1341 {
1342         u32 *history = po->rollover->history;
1343         u32 victim, rxhash;
1344         int i, count = 0;
1345
1346         rxhash = skb_get_hash(skb);
1347         for (i = 0; i < ROLLOVER_HLEN; i++)
1348                 if (READ_ONCE(history[i]) == rxhash)
1349                         count++;
1350
1351         victim = prandom_u32() % ROLLOVER_HLEN;
1352
1353         /* Avoid dirtying the cache line if possible */
1354         if (READ_ONCE(history[victim]) != rxhash)
1355                 WRITE_ONCE(history[victim], rxhash);
1356
1357         return count > (ROLLOVER_HLEN >> 1);
1358 }
1359
1360 static unsigned int fanout_demux_hash(struct packet_fanout *f,
1361                                       struct sk_buff *skb,
1362                                       unsigned int num)
1363 {
1364         return reciprocal_scale(__skb_get_hash_symmetric(skb), num);
1365 }
1366
1367 static unsigned int fanout_demux_lb(struct packet_fanout *f,
1368                                     struct sk_buff *skb,
1369                                     unsigned int num)
1370 {
1371         unsigned int val = atomic_inc_return(&f->rr_cur);
1372
1373         return val % num;
1374 }
1375
1376 static unsigned int fanout_demux_cpu(struct packet_fanout *f,
1377                                      struct sk_buff *skb,
1378                                      unsigned int num)
1379 {
1380         return smp_processor_id() % num;
1381 }
1382
1383 static unsigned int fanout_demux_rnd(struct packet_fanout *f,
1384                                      struct sk_buff *skb,
1385                                      unsigned int num)
1386 {
1387         return prandom_u32_max(num);
1388 }
1389
1390 static unsigned int fanout_demux_rollover(struct packet_fanout *f,
1391                                           struct sk_buff *skb,
1392                                           unsigned int idx, bool try_self,
1393                                           unsigned int num)
1394 {
1395         struct packet_sock *po, *po_next, *po_skip = NULL;
1396         unsigned int i, j, room = ROOM_NONE;
1397
1398         po = pkt_sk(f->arr[idx]);
1399
1400         if (try_self) {
1401                 room = packet_rcv_has_room(po, skb);
1402                 if (room == ROOM_NORMAL ||
1403                     (room == ROOM_LOW && !fanout_flow_is_huge(po, skb)))
1404                         return idx;
1405                 po_skip = po;
1406         }
1407
1408         i = j = min_t(int, po->rollover->sock, num - 1);
1409         do {
1410                 po_next = pkt_sk(f->arr[i]);
1411                 if (po_next != po_skip && !po_next->pressure &&
1412                     packet_rcv_has_room(po_next, skb) == ROOM_NORMAL) {
1413                         if (i != j)
1414                                 po->rollover->sock = i;
1415                         atomic_long_inc(&po->rollover->num);
1416                         if (room == ROOM_LOW)
1417                                 atomic_long_inc(&po->rollover->num_huge);
1418                         return i;
1419                 }
1420
1421                 if (++i == num)
1422                         i = 0;
1423         } while (i != j);
1424
1425         atomic_long_inc(&po->rollover->num_failed);
1426         return idx;
1427 }
1428
1429 static unsigned int fanout_demux_qm(struct packet_fanout *f,
1430                                     struct sk_buff *skb,
1431                                     unsigned int num)
1432 {
1433         return skb_get_queue_mapping(skb) % num;
1434 }
1435
1436 static unsigned int fanout_demux_bpf(struct packet_fanout *f,
1437                                      struct sk_buff *skb,
1438                                      unsigned int num)
1439 {
1440         struct bpf_prog *prog;
1441         unsigned int ret = 0;
1442
1443         rcu_read_lock();
1444         prog = rcu_dereference(f->bpf_prog);
1445         if (prog)
1446                 ret = bpf_prog_run_clear_cb(prog, skb) % num;
1447         rcu_read_unlock();
1448
1449         return ret;
1450 }
1451
1452 static bool fanout_has_flag(struct packet_fanout *f, u16 flag)
1453 {
1454         return f->flags & (flag >> 8);
1455 }
1456
1457 static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
1458                              struct packet_type *pt, struct net_device *orig_dev)
1459 {
1460         struct packet_fanout *f = pt->af_packet_priv;
1461         unsigned int num = READ_ONCE(f->num_members);
1462         struct net *net = read_pnet(&f->net);
1463         struct packet_sock *po;
1464         unsigned int idx;
1465
1466         if (!net_eq(dev_net(dev), net) || !num) {
1467                 kfree_skb(skb);
1468                 return 0;
1469         }
1470
1471         if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) {
1472                 skb = ip_check_defrag(net, skb, IP_DEFRAG_AF_PACKET);
1473                 if (!skb)
1474                         return 0;
1475         }
1476         switch (f->type) {
1477         case PACKET_FANOUT_HASH:
1478         default:
1479                 idx = fanout_demux_hash(f, skb, num);
1480                 break;
1481         case PACKET_FANOUT_LB:
1482                 idx = fanout_demux_lb(f, skb, num);
1483                 break;
1484         case PACKET_FANOUT_CPU:
1485                 idx = fanout_demux_cpu(f, skb, num);
1486                 break;
1487         case PACKET_FANOUT_RND:
1488                 idx = fanout_demux_rnd(f, skb, num);
1489                 break;
1490         case PACKET_FANOUT_QM:
1491                 idx = fanout_demux_qm(f, skb, num);
1492                 break;
1493         case PACKET_FANOUT_ROLLOVER:
1494                 idx = fanout_demux_rollover(f, skb, 0, false, num);
1495                 break;
1496         case PACKET_FANOUT_CBPF:
1497         case PACKET_FANOUT_EBPF:
1498                 idx = fanout_demux_bpf(f, skb, num);
1499                 break;
1500         }
1501
1502         if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER))
1503                 idx = fanout_demux_rollover(f, skb, idx, true, num);
1504
1505         po = pkt_sk(f->arr[idx]);
1506         return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
1507 }
1508
1509 DEFINE_MUTEX(fanout_mutex);
1510 EXPORT_SYMBOL_GPL(fanout_mutex);
1511 static LIST_HEAD(fanout_list);
1512 static u16 fanout_next_id;
1513
1514 static void __fanout_link(struct sock *sk, struct packet_sock *po)
1515 {
1516         struct packet_fanout *f = po->fanout;
1517
1518         spin_lock(&f->lock);
1519         f->arr[f->num_members] = sk;
1520         smp_wmb();
1521         f->num_members++;
1522         if (f->num_members == 1)
1523                 dev_add_pack(&f->prot_hook);
1524         spin_unlock(&f->lock);
1525 }
1526
1527 static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
1528 {
1529         struct packet_fanout *f = po->fanout;
1530         int i;
1531
1532         spin_lock(&f->lock);
1533         for (i = 0; i < f->num_members; i++) {
1534                 if (f->arr[i] == sk)
1535                         break;
1536         }
1537         BUG_ON(i >= f->num_members);
1538         f->arr[i] = f->arr[f->num_members - 1];
1539         f->num_members--;
1540         if (f->num_members == 0)
1541                 __dev_remove_pack(&f->prot_hook);
1542         spin_unlock(&f->lock);
1543 }
1544
1545 static bool match_fanout_group(struct packet_type *ptype, struct sock *sk)
1546 {
1547         if (sk->sk_family != PF_PACKET)
1548                 return false;
1549
1550         return ptype->af_packet_priv == pkt_sk(sk)->fanout;
1551 }
1552
1553 static void fanout_init_data(struct packet_fanout *f)
1554 {
1555         switch (f->type) {
1556         case PACKET_FANOUT_LB:
1557                 atomic_set(&f->rr_cur, 0);
1558                 break;
1559         case PACKET_FANOUT_CBPF:
1560         case PACKET_FANOUT_EBPF:
1561                 RCU_INIT_POINTER(f->bpf_prog, NULL);
1562                 break;
1563         }
1564 }
1565
1566 static void __fanout_set_data_bpf(struct packet_fanout *f, struct bpf_prog *new)
1567 {
1568         struct bpf_prog *old;
1569
1570         spin_lock(&f->lock);
1571         old = rcu_dereference_protected(f->bpf_prog, lockdep_is_held(&f->lock));
1572         rcu_assign_pointer(f->bpf_prog, new);
1573         spin_unlock(&f->lock);
1574
1575         if (old) {
1576                 synchronize_net();
1577                 bpf_prog_destroy(old);
1578         }
1579 }
1580
1581 static int fanout_set_data_cbpf(struct packet_sock *po, char __user *data,
1582                                 unsigned int len)
1583 {
1584         struct bpf_prog *new;
1585         struct sock_fprog fprog;
1586         int ret;
1587
1588         if (sock_flag(&po->sk, SOCK_FILTER_LOCKED))
1589                 return -EPERM;
1590         if (len != sizeof(fprog))
1591                 return -EINVAL;
1592         if (copy_from_user(&fprog, data, len))
1593                 return -EFAULT;
1594
1595         ret = bpf_prog_create_from_user(&new, &fprog, NULL, false);
1596         if (ret)
1597                 return ret;
1598
1599         __fanout_set_data_bpf(po->fanout, new);
1600         return 0;
1601 }
1602
1603 static int fanout_set_data_ebpf(struct packet_sock *po, char __user *data,
1604                                 unsigned int len)
1605 {
1606         struct bpf_prog *new;
1607         u32 fd;
1608
1609         if (sock_flag(&po->sk, SOCK_FILTER_LOCKED))
1610                 return -EPERM;
1611         if (len != sizeof(fd))
1612                 return -EINVAL;
1613         if (copy_from_user(&fd, data, len))
1614                 return -EFAULT;
1615
1616         new = bpf_prog_get_type(fd, BPF_PROG_TYPE_SOCKET_FILTER);
1617         if (IS_ERR(new))
1618                 return PTR_ERR(new);
1619
1620         __fanout_set_data_bpf(po->fanout, new);
1621         return 0;
1622 }
1623
1624 static int fanout_set_data(struct packet_sock *po, char __user *data,
1625                            unsigned int len)
1626 {
1627         switch (po->fanout->type) {
1628         case PACKET_FANOUT_CBPF:
1629                 return fanout_set_data_cbpf(po, data, len);
1630         case PACKET_FANOUT_EBPF:
1631                 return fanout_set_data_ebpf(po, data, len);
1632         default:
1633                 return -EINVAL;
1634         };
1635 }
1636
1637 static void fanout_release_data(struct packet_fanout *f)
1638 {
1639         switch (f->type) {
1640         case PACKET_FANOUT_CBPF:
1641         case PACKET_FANOUT_EBPF:
1642                 __fanout_set_data_bpf(f, NULL);
1643         };
1644 }
1645
1646 static bool __fanout_id_is_free(struct sock *sk, u16 candidate_id)
1647 {
1648         struct packet_fanout *f;
1649
1650         list_for_each_entry(f, &fanout_list, list) {
1651                 if (f->id == candidate_id &&
1652                     read_pnet(&f->net) == sock_net(sk)) {
1653                         return false;
1654                 }
1655         }
1656         return true;
1657 }
1658
1659 static bool fanout_find_new_id(struct sock *sk, u16 *new_id)
1660 {
1661         u16 id = fanout_next_id;
1662
1663         do {
1664                 if (__fanout_id_is_free(sk, id)) {
1665                         *new_id = id;
1666                         fanout_next_id = id + 1;
1667                         return true;
1668                 }
1669
1670                 id++;
1671         } while (id != fanout_next_id);
1672
1673         return false;
1674 }
1675
1676 static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
1677 {
1678         struct packet_rollover *rollover = NULL;
1679         struct packet_sock *po = pkt_sk(sk);
1680         struct packet_fanout *f, *match;
1681         u8 type = type_flags & 0xff;
1682         u8 flags = type_flags >> 8;
1683         int err;
1684
1685         switch (type) {
1686         case PACKET_FANOUT_ROLLOVER:
1687                 if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)
1688                         return -EINVAL;
1689         case PACKET_FANOUT_HASH:
1690         case PACKET_FANOUT_LB:
1691         case PACKET_FANOUT_CPU:
1692         case PACKET_FANOUT_RND:
1693         case PACKET_FANOUT_QM:
1694         case PACKET_FANOUT_CBPF:
1695         case PACKET_FANOUT_EBPF:
1696                 break;
1697         default:
1698                 return -EINVAL;
1699         }
1700
1701         mutex_lock(&fanout_mutex);
1702
1703         err = -EALREADY;
1704         if (po->fanout)
1705                 goto out;
1706
1707         if (type == PACKET_FANOUT_ROLLOVER ||
1708             (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)) {
1709                 err = -ENOMEM;
1710                 rollover = kzalloc(sizeof(*rollover), GFP_KERNEL);
1711                 if (!rollover)
1712                         goto out;
1713                 atomic_long_set(&rollover->num, 0);
1714                 atomic_long_set(&rollover->num_huge, 0);
1715                 atomic_long_set(&rollover->num_failed, 0);
1716         }
1717
1718         if (type_flags & PACKET_FANOUT_FLAG_UNIQUEID) {
1719                 if (id != 0) {
1720                         err = -EINVAL;
1721                         goto out;
1722                 }
1723                 if (!fanout_find_new_id(sk, &id)) {
1724                         err = -ENOMEM;
1725                         goto out;
1726                 }
1727                 /* ephemeral flag for the first socket in the group: drop it */
1728                 flags &= ~(PACKET_FANOUT_FLAG_UNIQUEID >> 8);
1729         }
1730
1731         match = NULL;
1732         list_for_each_entry(f, &fanout_list, list) {
1733                 if (f->id == id &&
1734                     read_pnet(&f->net) == sock_net(sk)) {
1735                         match = f;
1736                         break;
1737                 }
1738         }
1739         err = -EINVAL;
1740         if (match && match->flags != flags)
1741                 goto out;
1742         if (!match) {
1743                 err = -ENOMEM;
1744                 match = kzalloc(sizeof(*match), GFP_KERNEL);
1745                 if (!match)
1746                         goto out;
1747                 write_pnet(&match->net, sock_net(sk));
1748                 match->id = id;
1749                 match->type = type;
1750                 match->flags = flags;
1751                 INIT_LIST_HEAD(&match->list);
1752                 spin_lock_init(&match->lock);
1753                 refcount_set(&match->sk_ref, 0);
1754                 fanout_init_data(match);
1755                 match->prot_hook.type = po->prot_hook.type;
1756                 match->prot_hook.dev = po->prot_hook.dev;
1757                 match->prot_hook.func = packet_rcv_fanout;
1758                 match->prot_hook.af_packet_priv = match;
1759                 match->prot_hook.af_packet_net = read_pnet(&match->net);
1760                 match->prot_hook.id_match = match_fanout_group;
1761                 list_add(&match->list, &fanout_list);
1762         }
1763         err = -EINVAL;
1764
1765         spin_lock(&po->bind_lock);
1766         if (po->running &&
1767             match->type == type &&
1768             match->prot_hook.type == po->prot_hook.type &&
1769             match->prot_hook.dev == po->prot_hook.dev) {
1770                 err = -ENOSPC;
1771                 if (refcount_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
1772                         __dev_remove_pack(&po->prot_hook);
1773
1774                         /* Paired with packet_setsockopt(PACKET_FANOUT_DATA) */
1775                         WRITE_ONCE(po->fanout, match);
1776
1777                         po->rollover = rollover;
1778                         rollover = NULL;
1779                         refcount_set(&match->sk_ref, refcount_read(&match->sk_ref) + 1);
1780                         __fanout_link(sk, po);
1781                         err = 0;
1782                 }
1783         }
1784         spin_unlock(&po->bind_lock);
1785
1786         if (err && !refcount_read(&match->sk_ref)) {
1787                 list_del(&match->list);
1788                 kfree(match);
1789         }
1790
1791 out:
1792         kfree(rollover);
1793         mutex_unlock(&fanout_mutex);
1794         return err;
1795 }
1796
1797 /* If pkt_sk(sk)->fanout->sk_ref is zero, this function removes
1798  * pkt_sk(sk)->fanout from fanout_list and returns pkt_sk(sk)->fanout.
1799  * It is the responsibility of the caller to call fanout_release_data() and
1800  * free the returned packet_fanout (after synchronize_net())
1801  */
1802 static struct packet_fanout *fanout_release(struct sock *sk)
1803 {
1804         struct packet_sock *po = pkt_sk(sk);
1805         struct packet_fanout *f;
1806
1807         mutex_lock(&fanout_mutex);
1808         f = po->fanout;
1809         if (f) {
1810                 po->fanout = NULL;
1811
1812                 if (refcount_dec_and_test(&f->sk_ref))
1813                         list_del(&f->list);
1814                 else
1815                         f = NULL;
1816         }
1817         mutex_unlock(&fanout_mutex);
1818
1819         return f;
1820 }
1821
1822 static bool packet_extra_vlan_len_allowed(const struct net_device *dev,
1823                                           struct sk_buff *skb)
1824 {
1825         /* Earlier code assumed this would be a VLAN pkt, double-check
1826          * this now that we have the actual packet in hand. We can only
1827          * do this check on Ethernet devices.
1828          */
1829         if (unlikely(dev->type != ARPHRD_ETHER))
1830                 return false;
1831
1832         skb_reset_mac_header(skb);
1833         return likely(eth_hdr(skb)->h_proto == htons(ETH_P_8021Q));
1834 }
1835
1836 static const struct proto_ops packet_ops;
1837
1838 static const struct proto_ops packet_ops_spkt;
1839
1840 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
1841                            struct packet_type *pt, struct net_device *orig_dev)
1842 {
1843         struct sock *sk;
1844         struct sockaddr_pkt *spkt;
1845
1846         /*
1847          *      When we registered the protocol we saved the socket in the data
1848          *      field for just this event.
1849          */
1850
1851         sk = pt->af_packet_priv;
1852
1853         /*
1854          *      Yank back the headers [hope the device set this
1855          *      right or kerboom...]
1856          *
1857          *      Incoming packets have ll header pulled,
1858          *      push it back.
1859          *
1860          *      For outgoing ones skb->data == skb_mac_header(skb)
1861          *      so that this procedure is noop.
1862          */
1863
1864         if (skb->pkt_type == PACKET_LOOPBACK)
1865                 goto out;
1866
1867         if (!net_eq(dev_net(dev), sock_net(sk)))
1868                 goto out;
1869
1870         skb = skb_share_check(skb, GFP_ATOMIC);
1871         if (skb == NULL)
1872                 goto oom;
1873
1874         /* drop any routing info */
1875         skb_dst_drop(skb);
1876
1877         /* drop conntrack reference */
1878         nf_reset(skb);
1879
1880         spkt = &PACKET_SKB_CB(skb)->sa.pkt;
1881
1882         skb_push(skb, skb->data - skb_mac_header(skb));
1883
1884         /*
1885          *      The SOCK_PACKET socket receives _all_ frames.
1886          */
1887
1888         spkt->spkt_family = dev->type;
1889         strlcpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
1890         spkt->spkt_protocol = skb->protocol;
1891
1892         /*
1893          *      Charge the memory to the socket. This is done specifically
1894          *      to prevent sockets using all the memory up.
1895          */
1896
1897         if (sock_queue_rcv_skb(sk, skb) == 0)
1898                 return 0;
1899
1900 out:
1901         kfree_skb(skb);
1902 oom:
1903         return 0;
1904 }
1905
1906
1907 /*
1908  *      Output a raw packet to a device layer. This bypasses all the other
1909  *      protocol layers and you must therefore supply it with a complete frame
1910  */
1911
1912 static int packet_sendmsg_spkt(struct socket *sock, struct msghdr *msg,
1913                                size_t len)
1914 {
1915         struct sock *sk = sock->sk;
1916         DECLARE_SOCKADDR(struct sockaddr_pkt *, saddr, msg->msg_name);
1917         struct sk_buff *skb = NULL;
1918         struct net_device *dev;
1919         struct sockcm_cookie sockc;
1920         __be16 proto = 0;
1921         int err;
1922         int extra_len = 0;
1923
1924         /*
1925          *      Get and verify the address.
1926          */
1927
1928         if (saddr) {
1929                 if (msg->msg_namelen < sizeof(struct sockaddr))
1930                         return -EINVAL;
1931                 if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
1932                         proto = saddr->spkt_protocol;
1933         } else
1934                 return -ENOTCONN;       /* SOCK_PACKET must be sent giving an address */
1935
1936         /*
1937          *      Find the device first to size check it
1938          */
1939
1940         saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0;
1941 retry:
1942         rcu_read_lock();
1943         dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
1944         err = -ENODEV;
1945         if (dev == NULL)
1946                 goto out_unlock;
1947
1948         err = -ENETDOWN;
1949         if (!(dev->flags & IFF_UP))
1950                 goto out_unlock;
1951
1952         /*
1953          * You may not queue a frame bigger than the mtu. This is the lowest level
1954          * raw protocol and you must do your own fragmentation at this level.
1955          */
1956
1957         if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
1958                 if (!netif_supports_nofcs(dev)) {
1959                         err = -EPROTONOSUPPORT;
1960                         goto out_unlock;
1961                 }
1962                 extra_len = 4; /* We're doing our own CRC */
1963         }
1964
1965         err = -EMSGSIZE;
1966         if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len)
1967                 goto out_unlock;
1968
1969         if (!skb) {
1970                 size_t reserved = LL_RESERVED_SPACE(dev);
1971                 int tlen = dev->needed_tailroom;
1972                 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
1973
1974                 rcu_read_unlock();
1975                 skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL);
1976                 if (skb == NULL)
1977                         return -ENOBUFS;
1978                 /* FIXME: Save some space for broken drivers that write a hard
1979                  * header at transmission time by themselves. PPP is the notable
1980                  * one here. This should really be fixed at the driver level.
1981                  */
1982                 skb_reserve(skb, reserved);
1983                 skb_reset_network_header(skb);
1984
1985                 /* Try to align data part correctly */
1986                 if (hhlen) {
1987                         skb->data -= hhlen;
1988                         skb->tail -= hhlen;
1989                         if (len < hhlen)
1990                                 skb_reset_network_header(skb);
1991                 }
1992                 err = memcpy_from_msg(skb_put(skb, len), msg, len);
1993                 if (err)
1994                         goto out_free;
1995                 goto retry;
1996         }
1997
1998         if (!dev_validate_header(dev, skb->data, len)) {
1999                 err = -EINVAL;
2000                 goto out_unlock;
2001         }
2002         if (len > (dev->mtu + dev->hard_header_len + extra_len) &&
2003             !packet_extra_vlan_len_allowed(dev, skb)) {
2004                 err = -EMSGSIZE;
2005                 goto out_unlock;
2006         }
2007
2008         sockc.tsflags = sk->sk_tsflags;
2009         if (msg->msg_controllen) {
2010                 err = sock_cmsg_send(sk, msg, &sockc);
2011                 if (unlikely(err))
2012                         goto out_unlock;
2013         }
2014
2015         skb->protocol = proto;
2016         skb->dev = dev;
2017         skb->priority = sk->sk_priority;
2018         skb->mark = sk->sk_mark;
2019
2020         skb_setup_tx_timestamp(skb, sockc.tsflags);
2021
2022         if (unlikely(extra_len == 4))
2023                 skb->no_fcs = 1;
2024
2025         skb_probe_transport_header(skb, 0);
2026
2027         dev_queue_xmit(skb);
2028         rcu_read_unlock();
2029         return len;
2030
2031 out_unlock:
2032         rcu_read_unlock();
2033 out_free:
2034         kfree_skb(skb);
2035         return err;
2036 }
2037
2038 static unsigned int run_filter(struct sk_buff *skb,
2039                                const struct sock *sk,
2040                                unsigned int res)
2041 {
2042         struct sk_filter *filter;
2043
2044         rcu_read_lock();
2045         filter = rcu_dereference(sk->sk_filter);
2046         if (filter != NULL)
2047                 res = bpf_prog_run_clear_cb(filter->prog, skb);
2048         rcu_read_unlock();
2049
2050         return res;
2051 }
2052
2053 static int packet_rcv_vnet(struct msghdr *msg, const struct sk_buff *skb,
2054                            size_t *len)
2055 {
2056         struct virtio_net_hdr vnet_hdr;
2057
2058         if (*len < sizeof(vnet_hdr))
2059                 return -EINVAL;
2060         *len -= sizeof(vnet_hdr);
2061
2062         if (virtio_net_hdr_from_skb(skb, &vnet_hdr, vio_le(), true, 0))
2063                 return -EINVAL;
2064
2065         return memcpy_to_msg(msg, (void *)&vnet_hdr, sizeof(vnet_hdr));
2066 }
2067
2068 /*
2069  * This function makes lazy skb cloning in hope that most of packets
2070  * are discarded by BPF.
2071  *
2072  * Note tricky part: we DO mangle shared skb! skb->data, skb->len
2073  * and skb->cb are mangled. It works because (and until) packets
2074  * falling here are owned by current CPU. Output packets are cloned
2075  * by dev_queue_xmit_nit(), input packets are processed by net_bh
2076  * sequencially, so that if we return skb to original state on exit,
2077  * we will not harm anyone.
2078  */
2079
2080 static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
2081                       struct packet_type *pt, struct net_device *orig_dev)
2082 {
2083         struct sock *sk;
2084         struct sockaddr_ll *sll;
2085         struct packet_sock *po;
2086         u8 *skb_head = skb->data;
2087         int skb_len = skb->len;
2088         unsigned int snaplen, res;
2089         bool is_drop_n_account = false;
2090
2091         if (skb->pkt_type == PACKET_LOOPBACK)
2092                 goto drop;
2093
2094         sk = pt->af_packet_priv;
2095         po = pkt_sk(sk);
2096
2097         if (!net_eq(dev_net(dev), sock_net(sk)))
2098                 goto drop;
2099
2100         skb->dev = dev;
2101
2102         if (dev->header_ops) {
2103                 /* The device has an explicit notion of ll header,
2104                  * exported to higher levels.
2105                  *
2106                  * Otherwise, the device hides details of its frame
2107                  * structure, so that corresponding packet head is
2108                  * never delivered to user.
2109                  */
2110                 if (sk->sk_type != SOCK_DGRAM)
2111                         skb_push(skb, skb->data - skb_mac_header(skb));
2112                 else if (skb->pkt_type == PACKET_OUTGOING) {
2113                         /* Special case: outgoing packets have ll header at head */
2114                         skb_pull(skb, skb_network_offset(skb));
2115                 }
2116         }
2117
2118         snaplen = skb->len;
2119
2120         res = run_filter(skb, sk, snaplen);
2121         if (!res)
2122                 goto drop_n_restore;
2123         if (snaplen > res)
2124                 snaplen = res;
2125
2126         if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
2127                 goto drop_n_acct;
2128
2129         if (skb_shared(skb)) {
2130                 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
2131                 if (nskb == NULL)
2132                         goto drop_n_acct;
2133
2134                 if (skb_head != skb->data) {
2135                         skb->data = skb_head;
2136                         skb->len = skb_len;
2137                 }
2138                 consume_skb(skb);
2139                 skb = nskb;
2140         }
2141
2142         sock_skb_cb_check_size(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8);
2143
2144         sll = &PACKET_SKB_CB(skb)->sa.ll;
2145         sll->sll_hatype = dev->type;
2146         sll->sll_pkttype = skb->pkt_type;
2147         if (unlikely(po->origdev))
2148                 sll->sll_ifindex = orig_dev->ifindex;
2149         else
2150                 sll->sll_ifindex = dev->ifindex;
2151
2152         sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
2153
2154         /* sll->sll_family and sll->sll_protocol are set in packet_recvmsg().
2155          * Use their space for storing the original skb length.
2156          */
2157         PACKET_SKB_CB(skb)->sa.origlen = skb->len;
2158
2159         if (pskb_trim(skb, snaplen))
2160                 goto drop_n_acct;
2161
2162         skb_set_owner_r(skb, sk);
2163         skb->dev = NULL;
2164         skb_dst_drop(skb);
2165
2166         /* drop conntrack reference */
2167         nf_reset(skb);
2168
2169         spin_lock(&sk->sk_receive_queue.lock);
2170         po->stats.stats1.tp_packets++;
2171         sock_skb_set_dropcount(sk, skb);
2172         __skb_queue_tail(&sk->sk_receive_queue, skb);
2173         spin_unlock(&sk->sk_receive_queue.lock);
2174         sk->sk_data_ready(sk);
2175         return 0;
2176
2177 drop_n_acct:
2178         is_drop_n_account = true;
2179         spin_lock(&sk->sk_receive_queue.lock);
2180         po->stats.stats1.tp_drops++;
2181         atomic_inc(&sk->sk_drops);
2182         spin_unlock(&sk->sk_receive_queue.lock);
2183
2184 drop_n_restore:
2185         if (skb_head != skb->data && skb_shared(skb)) {
2186                 skb->data = skb_head;
2187                 skb->len = skb_len;
2188         }
2189 drop:
2190         if (!is_drop_n_account)
2191                 consume_skb(skb);
2192         else
2193                 kfree_skb(skb);
2194         return 0;
2195 }
2196
2197 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
2198                        struct packet_type *pt, struct net_device *orig_dev)
2199 {
2200         struct sock *sk;
2201         struct packet_sock *po;
2202         struct sockaddr_ll *sll;
2203         union tpacket_uhdr h;
2204         u8 *skb_head = skb->data;
2205         int skb_len = skb->len;
2206         unsigned int snaplen, res;
2207         unsigned long status = TP_STATUS_USER;
2208         unsigned short macoff, hdrlen;
2209         unsigned int netoff;
2210         struct sk_buff *copy_skb = NULL;
2211         struct timespec ts;
2212         __u32 ts_status;
2213         bool is_drop_n_account = false;
2214         unsigned int slot_id = 0;
2215         bool do_vnet = false;
2216
2217         /* struct tpacket{2,3}_hdr is aligned to a multiple of TPACKET_ALIGNMENT.
2218          * We may add members to them until current aligned size without forcing
2219          * userspace to call getsockopt(..., PACKET_HDRLEN, ...).
2220          */
2221         BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h2)) != 32);
2222         BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h3)) != 48);
2223
2224         if (skb->pkt_type == PACKET_LOOPBACK)
2225                 goto drop;
2226
2227         sk = pt->af_packet_priv;
2228         po = pkt_sk(sk);
2229
2230         if (!net_eq(dev_net(dev), sock_net(sk)))
2231                 goto drop;
2232
2233         if (dev->header_ops) {
2234                 if (sk->sk_type != SOCK_DGRAM)
2235                         skb_push(skb, skb->data - skb_mac_header(skb));
2236                 else if (skb->pkt_type == PACKET_OUTGOING) {
2237                         /* Special case: outgoing packets have ll header at head */
2238                         skb_pull(skb, skb_network_offset(skb));
2239                 }
2240         }
2241
2242         snaplen = skb->len;
2243
2244         res = run_filter(skb, sk, snaplen);
2245         if (!res)
2246                 goto drop_n_restore;
2247
2248         if (skb->ip_summed == CHECKSUM_PARTIAL)
2249                 status |= TP_STATUS_CSUMNOTREADY;
2250         else if (skb->pkt_type != PACKET_OUTGOING &&
2251                  skb_csum_unnecessary(skb))
2252                 status |= TP_STATUS_CSUM_VALID;
2253
2254         if (snaplen > res)
2255                 snaplen = res;
2256
2257         if (sk->sk_type == SOCK_DGRAM) {
2258                 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
2259                                   po->tp_reserve;
2260         } else {
2261                 unsigned int maclen = skb_network_offset(skb);
2262                 netoff = TPACKET_ALIGN(po->tp_hdrlen +
2263                                        (maclen < 16 ? 16 : maclen)) +
2264                                        po->tp_reserve;
2265                 if (po->has_vnet_hdr) {
2266                         netoff += sizeof(struct virtio_net_hdr);
2267                         do_vnet = true;
2268                 }
2269                 macoff = netoff - maclen;
2270         }
2271         if (netoff > USHRT_MAX) {
2272                 spin_lock(&sk->sk_receive_queue.lock);
2273                 po->stats.stats1.tp_drops++;
2274                 spin_unlock(&sk->sk_receive_queue.lock);
2275                 goto drop_n_restore;
2276         }
2277         if (po->tp_version <= TPACKET_V2) {
2278                 if (macoff + snaplen > po->rx_ring.frame_size) {
2279                         if (po->copy_thresh &&
2280                             atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
2281                                 if (skb_shared(skb)) {
2282                                         copy_skb = skb_clone(skb, GFP_ATOMIC);
2283                                 } else {
2284                                         copy_skb = skb_get(skb);
2285                                         skb_head = skb->data;
2286                                 }
2287                                 if (copy_skb) {
2288                                         memset(&PACKET_SKB_CB(copy_skb)->sa.ll, 0,
2289                                                sizeof(PACKET_SKB_CB(copy_skb)->sa.ll));
2290                                         skb_set_owner_r(copy_skb, sk);
2291                                 }
2292                         }
2293                         snaplen = po->rx_ring.frame_size - macoff;
2294                         if ((int)snaplen < 0) {
2295                                 snaplen = 0;
2296                                 do_vnet = false;
2297                         }
2298                 }
2299         } else if (unlikely(macoff + snaplen >
2300                             GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len)) {
2301                 u32 nval;
2302
2303                 nval = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len - macoff;
2304                 pr_err_once("tpacket_rcv: packet too big, clamped from %u to %u. macoff=%u\n",
2305                             snaplen, nval, macoff);
2306                 snaplen = nval;
2307                 if (unlikely((int)snaplen < 0)) {
2308                         snaplen = 0;
2309                         macoff = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len;
2310                         do_vnet = false;
2311                 }
2312         }
2313         spin_lock(&sk->sk_receive_queue.lock);
2314         h.raw = packet_current_rx_frame(po, skb,
2315                                         TP_STATUS_KERNEL, (macoff+snaplen));
2316         if (!h.raw)
2317                 goto drop_n_account;
2318
2319         if (po->tp_version <= TPACKET_V2) {
2320                 slot_id = po->rx_ring.head;
2321                 if (test_bit(slot_id, po->rx_ring.rx_owner_map))
2322                         goto drop_n_account;
2323                 __set_bit(slot_id, po->rx_ring.rx_owner_map);
2324         }
2325
2326         if (do_vnet &&
2327             virtio_net_hdr_from_skb(skb, h.raw + macoff -
2328                                     sizeof(struct virtio_net_hdr),
2329                                     vio_le(), true, 0)) {
2330                 if (po->tp_version == TPACKET_V3)
2331                         prb_clear_blk_fill_status(&po->rx_ring);
2332                 goto drop_n_account;
2333         }
2334
2335         if (po->tp_version <= TPACKET_V2) {
2336                 packet_increment_rx_head(po, &po->rx_ring);
2337         /*
2338          * LOSING will be reported till you read the stats,
2339          * because it's COR - Clear On Read.
2340          * Anyways, moving it for V1/V2 only as V3 doesn't need this
2341          * at packet level.
2342          */
2343                 if (po->stats.stats1.tp_drops)
2344                         status |= TP_STATUS_LOSING;
2345         }
2346
2347         po->stats.stats1.tp_packets++;
2348         if (copy_skb) {
2349                 status |= TP_STATUS_COPY;
2350                 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
2351         }
2352         spin_unlock(&sk->sk_receive_queue.lock);
2353
2354         skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
2355
2356         if (!(ts_status = tpacket_get_timestamp(skb, &ts, po->tp_tstamp)))
2357                 getnstimeofday(&ts);
2358
2359         status |= ts_status;
2360
2361         switch (po->tp_version) {
2362         case TPACKET_V1:
2363                 h.h1->tp_len = skb->len;
2364                 h.h1->tp_snaplen = snaplen;
2365                 h.h1->tp_mac = macoff;
2366                 h.h1->tp_net = netoff;
2367                 h.h1->tp_sec = ts.tv_sec;
2368                 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
2369                 hdrlen = sizeof(*h.h1);
2370                 break;
2371         case TPACKET_V2:
2372                 h.h2->tp_len = skb->len;
2373                 h.h2->tp_snaplen = snaplen;
2374                 h.h2->tp_mac = macoff;
2375                 h.h2->tp_net = netoff;
2376                 h.h2->tp_sec = ts.tv_sec;
2377                 h.h2->tp_nsec = ts.tv_nsec;
2378                 if (skb_vlan_tag_present(skb)) {
2379                         h.h2->tp_vlan_tci = skb_vlan_tag_get(skb);
2380                         h.h2->tp_vlan_tpid = ntohs(skb->vlan_proto);
2381                         status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
2382                 } else {
2383                         h.h2->tp_vlan_tci = 0;
2384                         h.h2->tp_vlan_tpid = 0;
2385                 }
2386                 memset(h.h2->tp_padding, 0, sizeof(h.h2->tp_padding));
2387                 hdrlen = sizeof(*h.h2);
2388                 break;
2389         case TPACKET_V3:
2390                 /* tp_nxt_offset,vlan are already populated above.
2391                  * So DONT clear those fields here
2392                  */
2393                 h.h3->tp_status |= status;
2394                 h.h3->tp_len = skb->len;
2395                 h.h3->tp_snaplen = snaplen;
2396                 h.h3->tp_mac = macoff;
2397                 h.h3->tp_net = netoff;
2398                 h.h3->tp_sec  = ts.tv_sec;
2399                 h.h3->tp_nsec = ts.tv_nsec;
2400                 memset(h.h3->tp_padding, 0, sizeof(h.h3->tp_padding));
2401                 hdrlen = sizeof(*h.h3);
2402                 break;
2403         default:
2404                 BUG();
2405         }
2406
2407         sll = h.raw + TPACKET_ALIGN(hdrlen);
2408         sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
2409         sll->sll_family = AF_PACKET;
2410         sll->sll_hatype = dev->type;
2411         sll->sll_protocol = skb->protocol;
2412         sll->sll_pkttype = skb->pkt_type;
2413         if (unlikely(po->origdev))
2414                 sll->sll_ifindex = orig_dev->ifindex;
2415         else
2416                 sll->sll_ifindex = dev->ifindex;
2417
2418         smp_mb();
2419
2420 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
2421         if (po->tp_version <= TPACKET_V2) {
2422                 u8 *start, *end;
2423
2424                 end = (u8 *) PAGE_ALIGN((unsigned long) h.raw +
2425                                         macoff + snaplen);
2426
2427                 for (start = h.raw; start < end; start += PAGE_SIZE)
2428                         flush_dcache_page(pgv_to_page(start));
2429         }
2430         smp_wmb();
2431 #endif
2432
2433         if (po->tp_version <= TPACKET_V2) {
2434                 spin_lock(&sk->sk_receive_queue.lock);
2435                 __packet_set_status(po, h.raw, status);
2436                 __clear_bit(slot_id, po->rx_ring.rx_owner_map);
2437                 spin_unlock(&sk->sk_receive_queue.lock);
2438                 sk->sk_data_ready(sk);
2439         } else if (po->tp_version == TPACKET_V3) {
2440                 prb_clear_blk_fill_status(&po->rx_ring);
2441         }
2442
2443 drop_n_restore:
2444         if (skb_head != skb->data && skb_shared(skb)) {
2445                 skb->data = skb_head;
2446                 skb->len = skb_len;
2447         }
2448 drop:
2449         if (!is_drop_n_account)
2450                 consume_skb(skb);
2451         else
2452                 kfree_skb(skb);
2453         return 0;
2454
2455 drop_n_account:
2456         is_drop_n_account = true;
2457         po->stats.stats1.tp_drops++;
2458         spin_unlock(&sk->sk_receive_queue.lock);
2459
2460         sk->sk_data_ready(sk);
2461         kfree_skb(copy_skb);
2462         goto drop_n_restore;
2463 }
2464
2465 static void tpacket_destruct_skb(struct sk_buff *skb)
2466 {
2467         struct packet_sock *po = pkt_sk(skb->sk);
2468
2469         if (likely(po->tx_ring.pg_vec)) {
2470                 void *ph;
2471                 __u32 ts;
2472
2473                 ph = skb_zcopy_get_nouarg(skb);
2474                 packet_dec_pending(&po->tx_ring);
2475
2476                 ts = __packet_set_timestamp(po, ph, skb);
2477                 __packet_set_status(po, ph, TP_STATUS_AVAILABLE | ts);
2478
2479                 if (!packet_read_pending(&po->tx_ring))
2480                         complete(&po->skb_completion);
2481         }
2482
2483         sock_wfree(skb);
2484 }
2485
2486 static void tpacket_set_protocol(const struct net_device *dev,
2487                                  struct sk_buff *skb)
2488 {
2489         if (dev->type == ARPHRD_ETHER) {
2490                 skb_reset_mac_header(skb);
2491                 skb->protocol = eth_hdr(skb)->h_proto;
2492         }
2493 }
2494
2495 static int __packet_snd_vnet_parse(struct virtio_net_hdr *vnet_hdr, size_t len)
2496 {
2497         if ((vnet_hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
2498             (__virtio16_to_cpu(vio_le(), vnet_hdr->csum_start) +
2499              __virtio16_to_cpu(vio_le(), vnet_hdr->csum_offset) + 2 >
2500               __virtio16_to_cpu(vio_le(), vnet_hdr->hdr_len)))
2501                 vnet_hdr->hdr_len = __cpu_to_virtio16(vio_le(),
2502                          __virtio16_to_cpu(vio_le(), vnet_hdr->csum_start) +
2503                         __virtio16_to_cpu(vio_le(), vnet_hdr->csum_offset) + 2);
2504
2505         if (__virtio16_to_cpu(vio_le(), vnet_hdr->hdr_len) > len)
2506                 return -EINVAL;
2507
2508         return 0;
2509 }
2510
2511 static int packet_snd_vnet_parse(struct msghdr *msg, size_t *len,
2512                                  struct virtio_net_hdr *vnet_hdr)
2513 {
2514         if (*len < sizeof(*vnet_hdr))
2515                 return -EINVAL;
2516         *len -= sizeof(*vnet_hdr);
2517
2518         if (!copy_from_iter_full(vnet_hdr, sizeof(*vnet_hdr), &msg->msg_iter))
2519                 return -EFAULT;
2520
2521         return __packet_snd_vnet_parse(vnet_hdr, *len);
2522 }
2523
2524 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
2525                 void *frame, struct net_device *dev, void *data, int tp_len,
2526                 __be16 proto, unsigned char *addr, int hlen, int copylen,
2527                 const struct sockcm_cookie *sockc)
2528 {
2529         union tpacket_uhdr ph;
2530         int to_write, offset, len, nr_frags, len_max;
2531         struct socket *sock = po->sk.sk_socket;
2532         struct page *page;
2533         int err;
2534
2535         ph.raw = frame;
2536
2537         skb->protocol = proto;
2538         skb->dev = dev;
2539         skb->priority = po->sk.sk_priority;
2540         skb->mark = po->sk.sk_mark;
2541         skb_setup_tx_timestamp(skb, sockc->tsflags);
2542         skb_zcopy_set_nouarg(skb, ph.raw);
2543
2544         skb_reserve(skb, hlen);
2545         skb_reset_network_header(skb);
2546
2547         to_write = tp_len;
2548
2549         if (sock->type == SOCK_DGRAM) {
2550                 err = dev_hard_header(skb, dev, ntohs(proto), addr,
2551                                 NULL, tp_len);
2552                 if (unlikely(err < 0))
2553                         return -EINVAL;
2554         } else if (copylen) {
2555                 int hdrlen = min_t(int, copylen, tp_len);
2556
2557                 skb_push(skb, dev->hard_header_len);
2558                 skb_put(skb, copylen - dev->hard_header_len);
2559                 err = skb_store_bits(skb, 0, data, hdrlen);
2560                 if (unlikely(err))
2561                         return err;
2562                 if (!dev_validate_header(dev, skb->data, hdrlen))
2563                         return -EINVAL;
2564                 if (!skb->protocol)
2565                         tpacket_set_protocol(dev, skb);
2566
2567                 data += hdrlen;
2568                 to_write -= hdrlen;
2569         }
2570
2571         offset = offset_in_page(data);
2572         len_max = PAGE_SIZE - offset;
2573         len = ((to_write > len_max) ? len_max : to_write);
2574
2575         skb->data_len = to_write;
2576         skb->len += to_write;
2577         skb->truesize += to_write;
2578         refcount_add(to_write, &po->sk.sk_wmem_alloc);
2579
2580         while (likely(to_write)) {
2581                 nr_frags = skb_shinfo(skb)->nr_frags;
2582
2583                 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
2584                         pr_err("Packet exceed the number of skb frags(%lu)\n",
2585                                MAX_SKB_FRAGS);
2586                         return -EFAULT;
2587                 }
2588
2589                 page = pgv_to_page(data);
2590                 data += len;
2591                 flush_dcache_page(page);
2592                 get_page(page);
2593                 skb_fill_page_desc(skb, nr_frags, page, offset, len);
2594                 to_write -= len;
2595                 offset = 0;
2596                 len_max = PAGE_SIZE;
2597                 len = ((to_write > len_max) ? len_max : to_write);
2598         }
2599
2600         skb_probe_transport_header(skb, 0);
2601
2602         return tp_len;
2603 }
2604
2605 static int tpacket_parse_header(struct packet_sock *po, void *frame,
2606                                 int size_max, void **data)
2607 {
2608         union tpacket_uhdr ph;
2609         int tp_len, off;
2610
2611         ph.raw = frame;
2612
2613         switch (po->tp_version) {
2614         case TPACKET_V3:
2615                 if (ph.h3->tp_next_offset != 0) {
2616                         pr_warn_once("variable sized slot not supported");
2617                         return -EINVAL;
2618                 }
2619                 tp_len = ph.h3->tp_len;
2620                 break;
2621         case TPACKET_V2:
2622                 tp_len = ph.h2->tp_len;
2623                 break;
2624         default:
2625                 tp_len = ph.h1->tp_len;
2626                 break;
2627         }
2628         if (unlikely(tp_len > size_max)) {
2629                 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
2630                 return -EMSGSIZE;
2631         }
2632
2633         if (unlikely(po->tp_tx_has_off)) {
2634                 int off_min, off_max;
2635
2636                 off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll);
2637                 off_max = po->tx_ring.frame_size - tp_len;
2638                 if (po->sk.sk_type == SOCK_DGRAM) {
2639                         switch (po->tp_version) {
2640                         case TPACKET_V3:
2641                                 off = ph.h3->tp_net;
2642                                 break;
2643                         case TPACKET_V2:
2644                                 off = ph.h2->tp_net;
2645                                 break;
2646                         default:
2647                                 off = ph.h1->tp_net;
2648                                 break;
2649                         }
2650                 } else {
2651                         switch (po->tp_version) {
2652                         case TPACKET_V3:
2653                                 off = ph.h3->tp_mac;
2654                                 break;
2655                         case TPACKET_V2:
2656                                 off = ph.h2->tp_mac;
2657                                 break;
2658                         default:
2659                                 off = ph.h1->tp_mac;
2660                                 break;
2661                         }
2662                 }
2663                 if (unlikely((off < off_min) || (off_max < off)))
2664                         return -EINVAL;
2665         } else {
2666                 off = po->tp_hdrlen - sizeof(struct sockaddr_ll);
2667         }
2668
2669         *data = frame + off;
2670         return tp_len;
2671 }
2672
2673 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
2674 {
2675         struct sk_buff *skb = NULL;
2676         struct net_device *dev;
2677         struct virtio_net_hdr *vnet_hdr = NULL;
2678         struct sockcm_cookie sockc;
2679         __be16 proto;
2680         int err, reserve = 0;
2681         void *ph;
2682         DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2683         bool need_wait = !(msg->msg_flags & MSG_DONTWAIT);
2684         unsigned char *addr = NULL;
2685         int tp_len, size_max;
2686         void *data;
2687         int len_sum = 0;
2688         int status = TP_STATUS_AVAILABLE;
2689         int hlen, tlen, copylen = 0;
2690         long timeo = 0;
2691
2692         mutex_lock(&po->pg_vec_lock);
2693
2694         /* packet_sendmsg() check on tx_ring.pg_vec was lockless,
2695          * we need to confirm it under protection of pg_vec_lock.
2696          */
2697         if (unlikely(!po->tx_ring.pg_vec)) {
2698                 err = -EBUSY;
2699                 goto out;
2700         }
2701         if (likely(saddr == NULL)) {
2702                 dev     = packet_cached_dev_get(po);
2703                 proto   = READ_ONCE(po->num);
2704         } else {
2705                 err = -EINVAL;
2706                 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2707                         goto out;
2708                 if (msg->msg_namelen < (saddr->sll_halen
2709                                         + offsetof(struct sockaddr_ll,
2710                                                 sll_addr)))
2711                         goto out;
2712                 proto   = saddr->sll_protocol;
2713                 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
2714                 if (po->sk.sk_socket->type == SOCK_DGRAM) {
2715                         if (dev && msg->msg_namelen < dev->addr_len +
2716                                    offsetof(struct sockaddr_ll, sll_addr))
2717                                 goto out_put;
2718                         addr = saddr->sll_addr;
2719                 }
2720         }
2721
2722         err = -ENXIO;
2723         if (unlikely(dev == NULL))
2724                 goto out;
2725         err = -ENETDOWN;
2726         if (unlikely(!(dev->flags & IFF_UP)))
2727                 goto out_put;
2728
2729         sockc.tsflags = po->sk.sk_tsflags;
2730         if (msg->msg_controllen) {
2731                 err = sock_cmsg_send(&po->sk, msg, &sockc);
2732                 if (unlikely(err))
2733                         goto out_put;
2734         }
2735
2736         if (po->sk.sk_socket->type == SOCK_RAW)
2737                 reserve = dev->hard_header_len;
2738         size_max = po->tx_ring.frame_size
2739                 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
2740
2741         if ((size_max > dev->mtu + reserve + VLAN_HLEN) && !po->has_vnet_hdr)
2742                 size_max = dev->mtu + reserve + VLAN_HLEN;
2743
2744         reinit_completion(&po->skb_completion);
2745
2746         do {
2747                 ph = packet_current_frame(po, &po->tx_ring,
2748                                           TP_STATUS_SEND_REQUEST);
2749                 if (unlikely(ph == NULL)) {
2750                         if (need_wait && skb) {
2751                                 timeo = sock_sndtimeo(&po->sk, msg->msg_flags & MSG_DONTWAIT);
2752                                 timeo = wait_for_completion_interruptible_timeout(&po->skb_completion, timeo);
2753                                 if (timeo <= 0) {
2754                                         err = !timeo ? -ETIMEDOUT : -ERESTARTSYS;
2755                                         goto out_put;
2756                                 }
2757                         }
2758                         /* check for additional frames */
2759                         continue;
2760                 }
2761
2762                 skb = NULL;
2763                 tp_len = tpacket_parse_header(po, ph, size_max, &data);
2764                 if (tp_len < 0)
2765                         goto tpacket_error;
2766
2767                 status = TP_STATUS_SEND_REQUEST;
2768                 hlen = LL_RESERVED_SPACE(dev);
2769                 tlen = dev->needed_tailroom;
2770                 if (po->has_vnet_hdr) {
2771                         vnet_hdr = data;
2772                         data += sizeof(*vnet_hdr);
2773                         tp_len -= sizeof(*vnet_hdr);
2774                         if (tp_len < 0 ||
2775                             __packet_snd_vnet_parse(vnet_hdr, tp_len)) {
2776                                 tp_len = -EINVAL;
2777                                 goto tpacket_error;
2778                         }
2779                         copylen = __virtio16_to_cpu(vio_le(),
2780                                                     vnet_hdr->hdr_len);
2781                 }
2782                 copylen = max_t(int, copylen, dev->hard_header_len);
2783                 skb = sock_alloc_send_skb(&po->sk,
2784                                 hlen + tlen + sizeof(struct sockaddr_ll) +
2785                                 (copylen - dev->hard_header_len),
2786                                 !need_wait, &err);
2787
2788                 if (unlikely(skb == NULL)) {
2789                         /* we assume the socket was initially writeable ... */
2790                         if (likely(len_sum > 0))
2791                                 err = len_sum;
2792                         goto out_status;
2793                 }
2794                 tp_len = tpacket_fill_skb(po, skb, ph, dev, data, tp_len, proto,
2795                                           addr, hlen, copylen, &sockc);
2796                 if (likely(tp_len >= 0) &&
2797                     tp_len > dev->mtu + reserve &&
2798                     !po->has_vnet_hdr &&
2799                     !packet_extra_vlan_len_allowed(dev, skb))
2800                         tp_len = -EMSGSIZE;
2801
2802                 if (unlikely(tp_len < 0)) {
2803 tpacket_error:
2804                         if (po->tp_loss) {
2805                                 __packet_set_status(po, ph,
2806                                                 TP_STATUS_AVAILABLE);
2807                                 packet_increment_head(&po->tx_ring);
2808                                 kfree_skb(skb);
2809                                 continue;
2810                         } else {
2811                                 status = TP_STATUS_WRONG_FORMAT;
2812                                 err = tp_len;
2813                                 goto out_status;
2814                         }
2815                 }
2816
2817                 if (po->has_vnet_hdr) {
2818                         if (virtio_net_hdr_to_skb(skb, vnet_hdr, vio_le())) {
2819                                 tp_len = -EINVAL;
2820                                 goto tpacket_error;
2821                         }
2822                         virtio_net_hdr_set_proto(skb, vnet_hdr);
2823                 }
2824
2825                 skb->destructor = tpacket_destruct_skb;
2826                 __packet_set_status(po, ph, TP_STATUS_SENDING);
2827                 packet_inc_pending(&po->tx_ring);
2828
2829                 status = TP_STATUS_SEND_REQUEST;
2830                 err = po->xmit(skb);
2831                 if (unlikely(err != 0)) {
2832                         if (err > 0)
2833                                 err = net_xmit_errno(err);
2834                         if (err && __packet_get_status(po, ph) ==
2835                                    TP_STATUS_AVAILABLE) {
2836                                 /* skb was destructed already */
2837                                 skb = NULL;
2838                                 goto out_status;
2839                         }
2840                         /*
2841                          * skb was dropped but not destructed yet;
2842                          * let's treat it like congestion or err < 0
2843                          */
2844                         err = 0;
2845                 }
2846                 packet_increment_head(&po->tx_ring);
2847                 len_sum += tp_len;
2848         } while (likely((ph != NULL) ||
2849                 /* Note: packet_read_pending() might be slow if we have
2850                  * to call it as it's per_cpu variable, but in fast-path
2851                  * we already short-circuit the loop with the first
2852                  * condition, and luckily don't have to go that path
2853                  * anyway.
2854                  */
2855                  (need_wait && packet_read_pending(&po->tx_ring))));
2856
2857         err = len_sum;
2858         goto out_put;
2859
2860 out_status:
2861         __packet_set_status(po, ph, status);
2862         kfree_skb(skb);
2863 out_put:
2864         dev_put(dev);
2865 out:
2866         mutex_unlock(&po->pg_vec_lock);
2867         return err;
2868 }
2869
2870 static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
2871                                         size_t reserve, size_t len,
2872                                         size_t linear, int noblock,
2873                                         int *err)
2874 {
2875         struct sk_buff *skb;
2876
2877         /* Under a page?  Don't bother with paged skb. */
2878         if (prepad + len < PAGE_SIZE || !linear)
2879                 linear = len;
2880
2881         skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
2882                                    err, 0);
2883         if (!skb)
2884                 return NULL;
2885
2886         skb_reserve(skb, reserve);
2887         skb_put(skb, linear);
2888         skb->data_len = len - linear;
2889         skb->len += len - linear;
2890
2891         return skb;
2892 }
2893
2894 static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
2895 {
2896         struct sock *sk = sock->sk;
2897         DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2898         struct sk_buff *skb;
2899         struct net_device *dev;
2900         __be16 proto;
2901         unsigned char *addr = NULL;
2902         int err, reserve = 0;
2903         struct sockcm_cookie sockc;
2904         struct virtio_net_hdr vnet_hdr = { 0 };
2905         int offset = 0;
2906         struct packet_sock *po = pkt_sk(sk);
2907         bool has_vnet_hdr = false;
2908         int hlen, tlen, linear;
2909         int extra_len = 0;
2910
2911         /*
2912          *      Get and verify the address.
2913          */
2914
2915         if (likely(saddr == NULL)) {
2916                 dev     = packet_cached_dev_get(po);
2917                 proto   = READ_ONCE(po->num);
2918         } else {
2919                 err = -EINVAL;
2920                 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2921                         goto out;
2922                 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
2923                         goto out;
2924                 proto   = saddr->sll_protocol;
2925                 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
2926                 if (sock->type == SOCK_DGRAM) {
2927                         if (dev && msg->msg_namelen < dev->addr_len +
2928                                    offsetof(struct sockaddr_ll, sll_addr))
2929                                 goto out_unlock;
2930                         addr = saddr->sll_addr;
2931                 }
2932         }
2933
2934         err = -ENXIO;
2935         if (unlikely(dev == NULL))
2936                 goto out_unlock;
2937         err = -ENETDOWN;
2938         if (unlikely(!(dev->flags & IFF_UP)))
2939                 goto out_unlock;
2940
2941         sockc.tsflags = sk->sk_tsflags;
2942         sockc.mark = sk->sk_mark;
2943         if (msg->msg_controllen) {
2944                 err = sock_cmsg_send(sk, msg, &sockc);
2945                 if (unlikely(err))
2946                         goto out_unlock;
2947         }
2948
2949         if (sock->type == SOCK_RAW)
2950                 reserve = dev->hard_header_len;
2951         if (po->has_vnet_hdr) {
2952                 err = packet_snd_vnet_parse(msg, &len, &vnet_hdr);
2953                 if (err)
2954                         goto out_unlock;
2955                 has_vnet_hdr = true;
2956         }
2957
2958         if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
2959                 if (!netif_supports_nofcs(dev)) {
2960                         err = -EPROTONOSUPPORT;
2961                         goto out_unlock;
2962                 }
2963                 extra_len = 4; /* We're doing our own CRC */
2964         }
2965
2966         err = -EMSGSIZE;
2967         if (!vnet_hdr.gso_type &&
2968             (len > dev->mtu + reserve + VLAN_HLEN + extra_len))
2969                 goto out_unlock;
2970
2971         err = -ENOBUFS;
2972         hlen = LL_RESERVED_SPACE(dev);
2973         tlen = dev->needed_tailroom;
2974         linear = __virtio16_to_cpu(vio_le(), vnet_hdr.hdr_len);
2975         linear = max(linear, min_t(int, len, dev->hard_header_len));
2976         skb = packet_alloc_skb(sk, hlen + tlen, hlen, len, linear,
2977                                msg->msg_flags & MSG_DONTWAIT, &err);
2978         if (skb == NULL)
2979                 goto out_unlock;
2980
2981         skb_reset_network_header(skb);
2982
2983         err = -EINVAL;
2984         if (sock->type == SOCK_DGRAM) {
2985                 offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len);
2986                 if (unlikely(offset < 0))
2987                         goto out_free;
2988         } else if (reserve) {
2989                 skb_reserve(skb, -reserve);
2990                 if (len < reserve)
2991                         skb_reset_network_header(skb);
2992         }
2993
2994         /* Returns -EFAULT on error */
2995         err = skb_copy_datagram_from_iter(skb, offset, &msg->msg_iter, len);
2996         if (err)
2997                 goto out_free;
2998
2999         if (sock->type == SOCK_RAW &&
3000             !dev_validate_header(dev, skb->data, len)) {
3001                 err = -EINVAL;
3002                 goto out_free;
3003         }
3004
3005         skb_setup_tx_timestamp(skb, sockc.tsflags);
3006
3007         if (!vnet_hdr.gso_type && (len > dev->mtu + reserve + extra_len) &&
3008             !packet_extra_vlan_len_allowed(dev, skb)) {
3009                 err = -EMSGSIZE;
3010                 goto out_free;
3011         }
3012
3013         skb->protocol = proto;
3014         skb->dev = dev;
3015         skb->priority = sk->sk_priority;
3016         skb->mark = sockc.mark;
3017
3018         if (has_vnet_hdr) {
3019                 err = virtio_net_hdr_to_skb(skb, &vnet_hdr, vio_le());
3020                 if (err)
3021                         goto out_free;
3022                 len += sizeof(vnet_hdr);
3023                 virtio_net_hdr_set_proto(skb, &vnet_hdr);
3024         }
3025
3026         skb_probe_transport_header(skb, reserve);
3027
3028         if (unlikely(extra_len == 4))
3029                 skb->no_fcs = 1;
3030
3031         err = po->xmit(skb);
3032         if (unlikely(err != 0)) {
3033                 if (err > 0)
3034                         err = net_xmit_errno(err);
3035                 if (err)
3036                         goto out_unlock;
3037         }
3038
3039         dev_put(dev);
3040
3041         return len;
3042
3043 out_free:
3044         kfree_skb(skb);
3045 out_unlock:
3046         if (dev)
3047                 dev_put(dev);
3048 out:
3049         return err;
3050 }
3051
3052 static int packet_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
3053 {
3054         struct sock *sk = sock->sk;
3055         struct packet_sock *po = pkt_sk(sk);
3056
3057         if (po->tx_ring.pg_vec)
3058                 return tpacket_snd(po, msg);
3059         else
3060                 return packet_snd(sock, msg, len);
3061 }
3062
3063 /*
3064  *      Close a PACKET socket. This is fairly simple. We immediately go
3065  *      to 'closed' state and remove our protocol entry in the device list.
3066  */
3067
3068 static int packet_release(struct socket *sock)
3069 {
3070         struct sock *sk = sock->sk;
3071         struct packet_sock *po;
3072         struct packet_fanout *f;
3073         struct net *net;
3074         union tpacket_req_u req_u;
3075
3076         if (!sk)
3077                 return 0;
3078
3079         net = sock_net(sk);
3080         po = pkt_sk(sk);
3081
3082         mutex_lock(&net->packet.sklist_lock);
3083         sk_del_node_init_rcu(sk);
3084         mutex_unlock(&net->packet.sklist_lock);
3085
3086         preempt_disable();
3087         sock_prot_inuse_add(net, sk->sk_prot, -1);
3088         preempt_enable();
3089
3090         spin_lock(&po->bind_lock);
3091         unregister_prot_hook(sk, false);
3092         packet_cached_dev_reset(po);
3093
3094         if (po->prot_hook.dev) {
3095                 dev_put(po->prot_hook.dev);
3096                 po->prot_hook.dev = NULL;
3097         }
3098         spin_unlock(&po->bind_lock);
3099
3100         packet_flush_mclist(sk);
3101
3102         lock_sock(sk);
3103         if (po->rx_ring.pg_vec) {
3104                 memset(&req_u, 0, sizeof(req_u));
3105                 packet_set_ring(sk, &req_u, 1, 0);
3106         }
3107
3108         if (po->tx_ring.pg_vec) {
3109                 memset(&req_u, 0, sizeof(req_u));
3110                 packet_set_ring(sk, &req_u, 1, 1);
3111         }
3112         release_sock(sk);
3113
3114         f = fanout_release(sk);
3115
3116         synchronize_net();
3117
3118         if (f) {
3119                 kfree(po->rollover);
3120                 fanout_release_data(f);
3121                 kfree(f);
3122         }
3123         /*
3124          *      Now the socket is dead. No more input will appear.
3125          */
3126         sock_orphan(sk);
3127         sock->sk = NULL;
3128
3129         /* Purge queues */
3130
3131         skb_queue_purge(&sk->sk_receive_queue);
3132         packet_free_pending(po);
3133         sk_refcnt_debug_release(sk);
3134
3135         sock_put(sk);
3136         return 0;
3137 }
3138
3139 /*
3140  *      Attach a packet hook.
3141  */
3142
3143 static int packet_do_bind(struct sock *sk, const char *name, int ifindex,
3144                           __be16 proto)
3145 {
3146         struct packet_sock *po = pkt_sk(sk);
3147         struct net_device *dev_curr;
3148         __be16 proto_curr;
3149         bool need_rehook;
3150         struct net_device *dev = NULL;
3151         int ret = 0;
3152         bool unlisted = false;
3153
3154         lock_sock(sk);
3155         spin_lock(&po->bind_lock);
3156         rcu_read_lock();
3157
3158         if (po->fanout) {
3159                 ret = -EINVAL;
3160                 goto out_unlock;
3161         }
3162
3163         if (name) {
3164                 dev = dev_get_by_name_rcu(sock_net(sk), name);
3165                 if (!dev) {
3166                         ret = -ENODEV;
3167                         goto out_unlock;
3168                 }
3169         } else if (ifindex) {
3170                 dev = dev_get_by_index_rcu(sock_net(sk), ifindex);
3171                 if (!dev) {
3172                         ret = -ENODEV;
3173                         goto out_unlock;
3174                 }
3175         }
3176
3177         if (dev)
3178                 dev_hold(dev);
3179
3180         proto_curr = po->prot_hook.type;
3181         dev_curr = po->prot_hook.dev;
3182
3183         need_rehook = proto_curr != proto || dev_curr != dev;
3184
3185         if (need_rehook) {
3186                 if (po->running) {
3187                         rcu_read_unlock();
3188                         /* prevents packet_notifier() from calling
3189                          * register_prot_hook()
3190                          */
3191                         WRITE_ONCE(po->num, 0);
3192                         __unregister_prot_hook(sk, true);
3193                         rcu_read_lock();
3194                         dev_curr = po->prot_hook.dev;
3195                         if (dev)
3196                                 unlisted = !dev_get_by_index_rcu(sock_net(sk),
3197                                                                  dev->ifindex);
3198                 }
3199
3200                 BUG_ON(po->running);
3201                 WRITE_ONCE(po->num, proto);
3202                 po->prot_hook.type = proto;
3203
3204                 if (unlikely(unlisted)) {
3205                         dev_put(dev);
3206                         po->prot_hook.dev = NULL;
3207                         WRITE_ONCE(po->ifindex, -1);
3208                         packet_cached_dev_reset(po);
3209                 } else {
3210                         po->prot_hook.dev = dev;
3211                         WRITE_ONCE(po->ifindex, dev ? dev->ifindex : 0);
3212                         packet_cached_dev_assign(po, dev);
3213                 }
3214         }
3215         if (dev_curr)
3216                 dev_put(dev_curr);
3217
3218         if (proto == 0 || !need_rehook)
3219                 goto out_unlock;
3220
3221         if (!unlisted && (!dev || (dev->flags & IFF_UP))) {
3222                 register_prot_hook(sk);
3223         } else {
3224                 sk->sk_err = ENETDOWN;
3225                 if (!sock_flag(sk, SOCK_DEAD))
3226                         sk->sk_error_report(sk);
3227         }
3228
3229 out_unlock:
3230         rcu_read_unlock();
3231         spin_unlock(&po->bind_lock);
3232         release_sock(sk);
3233         return ret;
3234 }
3235
3236 /*
3237  *      Bind a packet socket to a device
3238  */
3239
3240 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
3241                             int addr_len)
3242 {
3243         struct sock *sk = sock->sk;
3244         char name[sizeof(uaddr->sa_data) + 1];
3245
3246         /*
3247          *      Check legality
3248          */
3249
3250         if (addr_len != sizeof(struct sockaddr))
3251                 return -EINVAL;
3252         /* uaddr->sa_data comes from the userspace, it's not guaranteed to be
3253          * zero-terminated.
3254          */
3255         memcpy(name, uaddr->sa_data, sizeof(uaddr->sa_data));
3256         name[sizeof(uaddr->sa_data)] = 0;
3257
3258         return packet_do_bind(sk, name, 0, pkt_sk(sk)->num);
3259 }
3260
3261 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
3262 {
3263         struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
3264         struct sock *sk = sock->sk;
3265
3266         /*
3267          *      Check legality
3268          */
3269
3270         if (addr_len < sizeof(struct sockaddr_ll))
3271                 return -EINVAL;
3272         if (sll->sll_family != AF_PACKET)
3273                 return -EINVAL;
3274
3275         return packet_do_bind(sk, NULL, sll->sll_ifindex,
3276                               sll->sll_protocol ? : pkt_sk(sk)->num);
3277 }
3278
3279 static struct proto packet_proto = {
3280         .name     = "PACKET",
3281         .owner    = THIS_MODULE,
3282         .obj_size = sizeof(struct packet_sock),
3283 };
3284
3285 /*
3286  *      Create a packet of type SOCK_PACKET.
3287  */
3288
3289 static int packet_create(struct net *net, struct socket *sock, int protocol,
3290                          int kern)
3291 {
3292         struct sock *sk;
3293         struct packet_sock *po;
3294         __be16 proto = (__force __be16)protocol; /* weird, but documented */
3295         int err;
3296
3297         if (!ns_capable(net->user_ns, CAP_NET_RAW))
3298                 return -EPERM;
3299         if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
3300             sock->type != SOCK_PACKET)
3301                 return -ESOCKTNOSUPPORT;
3302
3303         sock->state = SS_UNCONNECTED;
3304
3305         err = -ENOBUFS;
3306         sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto, kern);
3307         if (sk == NULL)
3308                 goto out;
3309
3310         sock->ops = &packet_ops;
3311         if (sock->type == SOCK_PACKET)
3312                 sock->ops = &packet_ops_spkt;
3313
3314         sock_init_data(sock, sk);
3315
3316         po = pkt_sk(sk);
3317         init_completion(&po->skb_completion);
3318         sk->sk_family = PF_PACKET;
3319         po->num = proto;
3320         po->xmit = dev_queue_xmit;
3321
3322         err = packet_alloc_pending(po);
3323         if (err)
3324                 goto out2;
3325
3326         packet_cached_dev_reset(po);
3327
3328         sk->sk_destruct = packet_sock_destruct;
3329         sk_refcnt_debug_inc(sk);
3330
3331         /*
3332          *      Attach a protocol block
3333          */
3334
3335         spin_lock_init(&po->bind_lock);
3336         mutex_init(&po->pg_vec_lock);
3337         po->rollover = NULL;
3338         po->prot_hook.func = packet_rcv;
3339
3340         if (sock->type == SOCK_PACKET)
3341                 po->prot_hook.func = packet_rcv_spkt;
3342
3343         po->prot_hook.af_packet_priv = sk;
3344         po->prot_hook.af_packet_net = sock_net(sk);
3345
3346         if (proto) {
3347                 po->prot_hook.type = proto;
3348                 __register_prot_hook(sk);
3349         }
3350
3351         mutex_lock(&net->packet.sklist_lock);
3352         sk_add_node_tail_rcu(sk, &net->packet.sklist);
3353         mutex_unlock(&net->packet.sklist_lock);
3354
3355         preempt_disable();
3356         sock_prot_inuse_add(net, &packet_proto, 1);
3357         preempt_enable();
3358
3359         return 0;
3360 out2:
3361         sk_free(sk);
3362 out:
3363         return err;
3364 }
3365
3366 /*
3367  *      Pull a packet from our receive queue and hand it to the user.
3368  *      If necessary we block.
3369  */
3370
3371 static int packet_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
3372                           int flags)
3373 {
3374         struct sock *sk = sock->sk;
3375         struct sk_buff *skb;
3376         int copied, err;
3377         int vnet_hdr_len = 0;
3378         unsigned int origlen = 0;
3379
3380         err = -EINVAL;
3381         if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
3382                 goto out;
3383
3384 #if 0
3385         /* What error should we return now? EUNATTACH? */
3386         if (pkt_sk(sk)->ifindex < 0)
3387                 return -ENODEV;
3388 #endif
3389
3390         if (flags & MSG_ERRQUEUE) {
3391                 err = sock_recv_errqueue(sk, msg, len,
3392                                          SOL_PACKET, PACKET_TX_TIMESTAMP);
3393                 goto out;
3394         }
3395
3396         /*
3397          *      Call the generic datagram receiver. This handles all sorts
3398          *      of horrible races and re-entrancy so we can forget about it
3399          *      in the protocol layers.
3400          *
3401          *      Now it will return ENETDOWN, if device have just gone down,
3402          *      but then it will block.
3403          */
3404
3405         skb = skb_recv_datagram(sk, flags, flags & MSG_DONTWAIT, &err);
3406
3407         /*
3408          *      An error occurred so return it. Because skb_recv_datagram()
3409          *      handles the blocking we don't see and worry about blocking
3410          *      retries.
3411          */
3412
3413         if (skb == NULL)
3414                 goto out;
3415
3416         if (pkt_sk(sk)->pressure)
3417                 packet_rcv_has_room(pkt_sk(sk), NULL);
3418
3419         if (pkt_sk(sk)->has_vnet_hdr) {
3420                 err = packet_rcv_vnet(msg, skb, &len);
3421                 if (err)
3422                         goto out_free;
3423                 vnet_hdr_len = sizeof(struct virtio_net_hdr);
3424         }
3425
3426         /* You lose any data beyond the buffer you gave. If it worries
3427          * a user program they can ask the device for its MTU
3428          * anyway.
3429          */
3430         copied = skb->len;
3431         if (copied > len) {
3432                 copied = len;
3433                 msg->msg_flags |= MSG_TRUNC;
3434         }
3435
3436         err = skb_copy_datagram_msg(skb, 0, msg, copied);
3437         if (err)
3438                 goto out_free;
3439
3440         if (sock->type != SOCK_PACKET) {
3441                 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
3442
3443                 /* Original length was stored in sockaddr_ll fields */
3444                 origlen = PACKET_SKB_CB(skb)->sa.origlen;
3445                 sll->sll_family = AF_PACKET;
3446                 sll->sll_protocol = skb->protocol;
3447         }
3448
3449         sock_recv_ts_and_drops(msg, sk, skb);
3450
3451         if (msg->msg_name) {
3452                 const size_t max_len = min(sizeof(skb->cb),
3453                                            sizeof(struct sockaddr_storage));
3454                 int copy_len;
3455
3456                 /* If the address length field is there to be filled
3457                  * in, we fill it in now.
3458                  */
3459                 if (sock->type == SOCK_PACKET) {
3460                         __sockaddr_check_size(sizeof(struct sockaddr_pkt));
3461                         msg->msg_namelen = sizeof(struct sockaddr_pkt);
3462                         copy_len = msg->msg_namelen;
3463                 } else {
3464                         struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
3465
3466                         msg->msg_namelen = sll->sll_halen +
3467                                 offsetof(struct sockaddr_ll, sll_addr);
3468                         copy_len = msg->msg_namelen;
3469                         if (msg->msg_namelen < sizeof(struct sockaddr_ll)) {
3470                                 memset(msg->msg_name +
3471                                        offsetof(struct sockaddr_ll, sll_addr),
3472                                        0, sizeof(sll->sll_addr));
3473                                 msg->msg_namelen = sizeof(struct sockaddr_ll);
3474                         }
3475                 }
3476                 if (WARN_ON_ONCE(copy_len > max_len)) {
3477                         copy_len = max_len;
3478                         msg->msg_namelen = copy_len;
3479                 }
3480                 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa, copy_len);
3481         }
3482
3483         if (pkt_sk(sk)->auxdata) {
3484                 struct tpacket_auxdata aux;
3485
3486                 aux.tp_status = TP_STATUS_USER;
3487                 if (skb->ip_summed == CHECKSUM_PARTIAL)
3488                         aux.tp_status |= TP_STATUS_CSUMNOTREADY;
3489                 else if (skb->pkt_type != PACKET_OUTGOING &&
3490                          skb_csum_unnecessary(skb))
3491                         aux.tp_status |= TP_STATUS_CSUM_VALID;
3492
3493                 aux.tp_len = origlen;
3494                 aux.tp_snaplen = skb->len;
3495                 aux.tp_mac = 0;
3496                 aux.tp_net = skb_network_offset(skb);
3497                 if (skb_vlan_tag_present(skb)) {
3498                         aux.tp_vlan_tci = skb_vlan_tag_get(skb);
3499                         aux.tp_vlan_tpid = ntohs(skb->vlan_proto);
3500                         aux.tp_status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
3501                 } else {
3502                         aux.tp_vlan_tci = 0;
3503                         aux.tp_vlan_tpid = 0;
3504                 }
3505                 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
3506         }
3507
3508         /*
3509          *      Free or return the buffer as appropriate. Again this
3510          *      hides all the races and re-entrancy issues from us.
3511          */
3512         err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
3513
3514 out_free:
3515         skb_free_datagram(sk, skb);
3516 out:
3517         return err;
3518 }
3519
3520 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
3521                                int *uaddr_len, int peer)
3522 {
3523         struct net_device *dev;
3524         struct sock *sk = sock->sk;
3525
3526         if (peer)
3527                 return -EOPNOTSUPP;
3528
3529         uaddr->sa_family = AF_PACKET;
3530         memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data));
3531         rcu_read_lock();
3532         dev = dev_get_by_index_rcu(sock_net(sk), READ_ONCE(pkt_sk(sk)->ifindex));
3533         if (dev)
3534                 strlcpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data));
3535         rcu_read_unlock();
3536         *uaddr_len = sizeof(*uaddr);
3537
3538         return 0;
3539 }
3540
3541 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
3542                           int *uaddr_len, int peer)
3543 {
3544         struct net_device *dev;
3545         struct sock *sk = sock->sk;
3546         struct packet_sock *po = pkt_sk(sk);
3547         DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
3548         int ifindex;
3549
3550         if (peer)
3551                 return -EOPNOTSUPP;
3552
3553         ifindex = READ_ONCE(po->ifindex);
3554         sll->sll_family = AF_PACKET;
3555         sll->sll_ifindex = ifindex;
3556         sll->sll_protocol = READ_ONCE(po->num);
3557         sll->sll_pkttype = 0;
3558         rcu_read_lock();
3559         dev = dev_get_by_index_rcu(sock_net(sk), ifindex);
3560         if (dev) {
3561                 sll->sll_hatype = dev->type;
3562                 sll->sll_halen = dev->addr_len;
3563                 memcpy(sll->sll_addr, dev->dev_addr, dev->addr_len);
3564         } else {
3565                 sll->sll_hatype = 0;    /* Bad: we have no ARPHRD_UNSPEC */
3566                 sll->sll_halen = 0;
3567         }
3568         rcu_read_unlock();
3569         *uaddr_len = offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
3570
3571         return 0;
3572 }
3573
3574 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
3575                          int what)
3576 {
3577         switch (i->type) {
3578         case PACKET_MR_MULTICAST:
3579                 if (i->alen != dev->addr_len)
3580                         return -EINVAL;
3581                 if (what > 0)
3582                         return dev_mc_add(dev, i->addr);
3583                 else
3584                         return dev_mc_del(dev, i->addr);
3585                 break;
3586         case PACKET_MR_PROMISC:
3587                 return dev_set_promiscuity(dev, what);
3588         case PACKET_MR_ALLMULTI:
3589                 return dev_set_allmulti(dev, what);
3590         case PACKET_MR_UNICAST:
3591                 if (i->alen != dev->addr_len)
3592                         return -EINVAL;
3593                 if (what > 0)
3594                         return dev_uc_add(dev, i->addr);
3595                 else
3596                         return dev_uc_del(dev, i->addr);
3597                 break;
3598         default:
3599                 break;
3600         }
3601         return 0;
3602 }
3603
3604 static void packet_dev_mclist_delete(struct net_device *dev,
3605                                      struct packet_mclist **mlp)
3606 {
3607         struct packet_mclist *ml;
3608
3609         while ((ml = *mlp) != NULL) {
3610                 if (ml->ifindex == dev->ifindex) {
3611                         packet_dev_mc(dev, ml, -1);
3612                         *mlp = ml->next;
3613                         kfree(ml);
3614                 } else
3615                         mlp = &ml->next;
3616         }
3617 }
3618
3619 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
3620 {
3621         struct packet_sock *po = pkt_sk(sk);
3622         struct packet_mclist *ml, *i;
3623         struct net_device *dev;
3624         int err;
3625
3626         rtnl_lock();
3627
3628         err = -ENODEV;
3629         dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
3630         if (!dev)
3631                 goto done;
3632
3633         err = -EINVAL;
3634         if (mreq->mr_alen > dev->addr_len)
3635                 goto done;
3636
3637         err = -ENOBUFS;
3638         i = kmalloc(sizeof(*i), GFP_KERNEL);
3639         if (i == NULL)
3640                 goto done;
3641
3642         err = 0;
3643         for (ml = po->mclist; ml; ml = ml->next) {
3644                 if (ml->ifindex == mreq->mr_ifindex &&
3645                     ml->type == mreq->mr_type &&
3646                     ml->alen == mreq->mr_alen &&
3647                     memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3648                         ml->count++;
3649                         /* Free the new element ... */
3650                         kfree(i);
3651                         goto done;
3652                 }
3653         }
3654
3655         i->type = mreq->mr_type;
3656         i->ifindex = mreq->mr_ifindex;
3657         i->alen = mreq->mr_alen;
3658         memcpy(i->addr, mreq->mr_address, i->alen);
3659         memset(i->addr + i->alen, 0, sizeof(i->addr) - i->alen);
3660         i->count = 1;
3661         i->next = po->mclist;
3662         po->mclist = i;
3663         err = packet_dev_mc(dev, i, 1);
3664         if (err) {
3665                 po->mclist = i->next;
3666                 kfree(i);
3667         }
3668
3669 done:
3670         rtnl_unlock();
3671         return err;
3672 }
3673
3674 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
3675 {
3676         struct packet_mclist *ml, **mlp;
3677
3678         rtnl_lock();
3679
3680         for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
3681                 if (ml->ifindex == mreq->mr_ifindex &&
3682                     ml->type == mreq->mr_type &&
3683                     ml->alen == mreq->mr_alen &&
3684                     memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3685                         if (--ml->count == 0) {
3686                                 struct net_device *dev;
3687                                 *mlp = ml->next;
3688                                 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3689                                 if (dev)
3690                                         packet_dev_mc(dev, ml, -1);
3691                                 kfree(ml);
3692                         }
3693                         break;
3694                 }
3695         }
3696         rtnl_unlock();
3697         return 0;
3698 }
3699
3700 static void packet_flush_mclist(struct sock *sk)
3701 {
3702         struct packet_sock *po = pkt_sk(sk);
3703         struct packet_mclist *ml;
3704
3705         if (!po->mclist)
3706                 return;
3707
3708         rtnl_lock();
3709         while ((ml = po->mclist) != NULL) {
3710                 struct net_device *dev;
3711
3712                 po->mclist = ml->next;
3713                 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3714                 if (dev != NULL)
3715                         packet_dev_mc(dev, ml, -1);
3716                 kfree(ml);
3717         }
3718         rtnl_unlock();
3719 }
3720
3721 static int
3722 packet_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
3723 {
3724         struct sock *sk = sock->sk;
3725         struct packet_sock *po = pkt_sk(sk);
3726         int ret;
3727
3728         if (level != SOL_PACKET)
3729                 return -ENOPROTOOPT;
3730
3731         switch (optname) {
3732         case PACKET_ADD_MEMBERSHIP:
3733         case PACKET_DROP_MEMBERSHIP:
3734         {
3735                 struct packet_mreq_max mreq;
3736                 int len = optlen;
3737                 memset(&mreq, 0, sizeof(mreq));
3738                 if (len < sizeof(struct packet_mreq))
3739                         return -EINVAL;
3740                 if (len > sizeof(mreq))
3741                         len = sizeof(mreq);
3742                 if (copy_from_user(&mreq, optval, len))
3743                         return -EFAULT;
3744                 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
3745                         return -EINVAL;
3746                 if (optname == PACKET_ADD_MEMBERSHIP)
3747                         ret = packet_mc_add(sk, &mreq);
3748                 else
3749                         ret = packet_mc_drop(sk, &mreq);
3750                 return ret;
3751         }
3752
3753         case PACKET_RX_RING:
3754         case PACKET_TX_RING:
3755         {
3756                 union tpacket_req_u req_u;
3757                 int len;
3758
3759                 lock_sock(sk);
3760                 switch (po->tp_version) {
3761                 case TPACKET_V1:
3762                 case TPACKET_V2:
3763                         len = sizeof(req_u.req);
3764                         break;
3765                 case TPACKET_V3:
3766                 default:
3767                         len = sizeof(req_u.req3);
3768                         break;
3769                 }
3770                 if (optlen < len) {
3771                         ret = -EINVAL;
3772                 } else {
3773                         if (copy_from_user(&req_u.req, optval, len))
3774                                 ret = -EFAULT;
3775                         else
3776                                 ret = packet_set_ring(sk, &req_u, 0,
3777                                                     optname == PACKET_TX_RING);
3778                 }
3779                 release_sock(sk);
3780                 return ret;
3781         }
3782         case PACKET_COPY_THRESH:
3783         {
3784                 int val;
3785
3786                 if (optlen != sizeof(val))
3787                         return -EINVAL;
3788                 if (copy_from_user(&val, optval, sizeof(val)))
3789                         return -EFAULT;
3790
3791                 pkt_sk(sk)->copy_thresh = val;
3792                 return 0;
3793         }
3794         case PACKET_VERSION:
3795         {
3796                 int val;
3797
3798                 if (optlen != sizeof(val))
3799                         return -EINVAL;
3800                 if (copy_from_user(&val, optval, sizeof(val)))
3801                         return -EFAULT;
3802                 switch (val) {
3803                 case TPACKET_V1:
3804                 case TPACKET_V2:
3805                 case TPACKET_V3:
3806                         break;
3807                 default:
3808                         return -EINVAL;
3809                 }
3810                 lock_sock(sk);
3811                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
3812                         ret = -EBUSY;
3813                 } else {
3814                         po->tp_version = val;
3815                         ret = 0;
3816                 }
3817                 release_sock(sk);
3818                 return ret;
3819         }
3820         case PACKET_RESERVE:
3821         {
3822                 unsigned int val;
3823
3824                 if (optlen != sizeof(val))
3825                         return -EINVAL;
3826                 if (copy_from_user(&val, optval, sizeof(val)))
3827                         return -EFAULT;
3828                 if (val > INT_MAX)
3829                         return -EINVAL;
3830                 lock_sock(sk);
3831                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
3832                         ret = -EBUSY;
3833                 } else {
3834                         po->tp_reserve = val;
3835                         ret = 0;
3836                 }
3837                 release_sock(sk);
3838                 return ret;
3839         }
3840         case PACKET_LOSS:
3841         {
3842                 unsigned int val;
3843
3844                 if (optlen != sizeof(val))
3845                         return -EINVAL;
3846                 if (copy_from_user(&val, optval, sizeof(val)))
3847                         return -EFAULT;
3848
3849                 lock_sock(sk);
3850                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
3851                         ret = -EBUSY;
3852                 } else {
3853                         po->tp_loss = !!val;
3854                         ret = 0;
3855                 }
3856                 release_sock(sk);
3857                 return ret;
3858         }
3859         case PACKET_AUXDATA:
3860         {
3861                 int val;
3862
3863                 if (optlen < sizeof(val))
3864                         return -EINVAL;
3865                 if (copy_from_user(&val, optval, sizeof(val)))
3866                         return -EFAULT;
3867
3868                 lock_sock(sk);
3869                 po->auxdata = !!val;
3870                 release_sock(sk);
3871                 return 0;
3872         }
3873         case PACKET_ORIGDEV:
3874         {
3875                 int val;
3876
3877                 if (optlen < sizeof(val))
3878                         return -EINVAL;
3879                 if (copy_from_user(&val, optval, sizeof(val)))
3880                         return -EFAULT;
3881
3882                 lock_sock(sk);
3883                 po->origdev = !!val;
3884                 release_sock(sk);
3885                 return 0;
3886         }
3887         case PACKET_VNET_HDR:
3888         {
3889                 int val;
3890
3891                 if (sock->type != SOCK_RAW)
3892                         return -EINVAL;
3893                 if (optlen < sizeof(val))
3894                         return -EINVAL;
3895                 if (copy_from_user(&val, optval, sizeof(val)))
3896                         return -EFAULT;
3897
3898                 lock_sock(sk);
3899                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
3900                         ret = -EBUSY;
3901                 } else {
3902                         po->has_vnet_hdr = !!val;
3903                         ret = 0;
3904                 }
3905                 release_sock(sk);
3906                 return ret;
3907         }
3908         case PACKET_TIMESTAMP:
3909         {
3910                 int val;
3911
3912                 if (optlen != sizeof(val))
3913                         return -EINVAL;
3914                 if (copy_from_user(&val, optval, sizeof(val)))
3915                         return -EFAULT;
3916
3917                 po->tp_tstamp = val;
3918                 return 0;
3919         }
3920         case PACKET_FANOUT:
3921         {
3922                 int val;
3923
3924                 if (optlen != sizeof(val))
3925                         return -EINVAL;
3926                 if (copy_from_user(&val, optval, sizeof(val)))
3927                         return -EFAULT;
3928
3929                 return fanout_add(sk, val & 0xffff, val >> 16);
3930         }
3931         case PACKET_FANOUT_DATA:
3932         {
3933                 /* Paired with the WRITE_ONCE() in fanout_add() */
3934                 if (!READ_ONCE(po->fanout))
3935                         return -EINVAL;
3936
3937                 return fanout_set_data(po, optval, optlen);
3938         }
3939         case PACKET_TX_HAS_OFF:
3940         {
3941                 unsigned int val;
3942
3943                 if (optlen != sizeof(val))
3944                         return -EINVAL;
3945                 if (copy_from_user(&val, optval, sizeof(val)))
3946                         return -EFAULT;
3947
3948                 lock_sock(sk);
3949                 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
3950                         ret = -EBUSY;
3951                 } else {
3952                         po->tp_tx_has_off = !!val;
3953                         ret = 0;
3954                 }
3955                 release_sock(sk);
3956                 return 0;
3957         }
3958         case PACKET_QDISC_BYPASS:
3959         {
3960                 int val;
3961
3962                 if (optlen != sizeof(val))
3963                         return -EINVAL;
3964                 if (copy_from_user(&val, optval, sizeof(val)))
3965                         return -EFAULT;
3966
3967                 po->xmit = val ? packet_direct_xmit : dev_queue_xmit;
3968                 return 0;
3969         }
3970         default:
3971                 return -ENOPROTOOPT;
3972         }
3973 }
3974
3975 static int packet_getsockopt(struct socket *sock, int level, int optname,
3976                              char __user *optval, int __user *optlen)
3977 {
3978         int len;
3979         int val, lv = sizeof(val);
3980         struct sock *sk = sock->sk;
3981         struct packet_sock *po = pkt_sk(sk);
3982         void *data = &val;
3983         union tpacket_stats_u st;
3984         struct tpacket_rollover_stats rstats;
3985
3986         if (level != SOL_PACKET)
3987                 return -ENOPROTOOPT;
3988
3989         if (get_user(len, optlen))
3990                 return -EFAULT;
3991
3992         if (len < 0)
3993                 return -EINVAL;
3994
3995         switch (optname) {
3996         case PACKET_STATISTICS:
3997                 spin_lock_bh(&sk->sk_receive_queue.lock);
3998                 memcpy(&st, &po->stats, sizeof(st));
3999                 memset(&po->stats, 0, sizeof(po->stats));
4000                 spin_unlock_bh(&sk->sk_receive_queue.lock);
4001
4002                 if (po->tp_version == TPACKET_V3) {
4003                         lv = sizeof(struct tpacket_stats_v3);
4004                         st.stats3.tp_packets += st.stats3.tp_drops;
4005                         data = &st.stats3;
4006                 } else {
4007                         lv = sizeof(struct tpacket_stats);
4008                         st.stats1.tp_packets += st.stats1.tp_drops;
4009                         data = &st.stats1;
4010                 }
4011
4012                 break;
4013         case PACKET_AUXDATA:
4014                 val = po->auxdata;
4015                 break;
4016         case PACKET_ORIGDEV:
4017                 val = po->origdev;
4018                 break;
4019         case PACKET_VNET_HDR:
4020                 val = po->has_vnet_hdr;
4021                 break;
4022         case PACKET_VERSION:
4023                 val = po->tp_version;
4024                 break;
4025         case PACKET_HDRLEN:
4026                 if (len > sizeof(int))
4027                         len = sizeof(int);
4028                 if (len < sizeof(int))
4029                         return -EINVAL;
4030                 if (copy_from_user(&val, optval, len))
4031                         return -EFAULT;
4032                 switch (val) {
4033                 case TPACKET_V1:
4034                         val = sizeof(struct tpacket_hdr);
4035                         break;
4036                 case TPACKET_V2:
4037                         val = sizeof(struct tpacket2_hdr);
4038                         break;
4039                 case TPACKET_V3:
4040                         val = sizeof(struct tpacket3_hdr);
4041                         break;
4042                 default:
4043                         return -EINVAL;
4044                 }
4045                 break;
4046         case PACKET_RESERVE:
4047                 val = po->tp_reserve;
4048                 break;
4049         case PACKET_LOSS:
4050                 val = po->tp_loss;
4051                 break;
4052         case PACKET_TIMESTAMP:
4053                 val = po->tp_tstamp;
4054                 break;
4055         case PACKET_FANOUT:
4056                 val = (po->fanout ?
4057                        ((u32)po->fanout->id |
4058                         ((u32)po->fanout->type << 16) |
4059                         ((u32)po->fanout->flags << 24)) :
4060                        0);
4061                 break;
4062         case PACKET_ROLLOVER_STATS:
4063                 if (!po->rollover)
4064                         return -EINVAL;
4065                 rstats.tp_all = atomic_long_read(&po->rollover->num);
4066                 rstats.tp_huge = atomic_long_read(&po->rollover->num_huge);
4067                 rstats.tp_failed = atomic_long_read(&po->rollover->num_failed);
4068                 data = &rstats;
4069                 lv = sizeof(rstats);
4070                 break;
4071         case PACKET_TX_HAS_OFF:
4072                 val = po->tp_tx_has_off;
4073                 break;
4074         case PACKET_QDISC_BYPASS:
4075                 val = packet_use_direct_xmit(po);
4076                 break;
4077         default:
4078                 return -ENOPROTOOPT;
4079         }
4080
4081         if (len > lv)
4082                 len = lv;
4083         if (put_user(len, optlen))
4084                 return -EFAULT;
4085         if (copy_to_user(optval, data, len))
4086                 return -EFAULT;
4087         return 0;
4088 }
4089
4090
4091 #ifdef CONFIG_COMPAT
4092 static int compat_packet_setsockopt(struct socket *sock, int level, int optname,
4093                                     char __user *optval, unsigned int optlen)
4094 {
4095         struct packet_sock *po = pkt_sk(sock->sk);
4096
4097         if (level != SOL_PACKET)
4098                 return -ENOPROTOOPT;
4099
4100         if (optname == PACKET_FANOUT_DATA &&
4101             po->fanout && po->fanout->type == PACKET_FANOUT_CBPF) {
4102                 optval = (char __user *)get_compat_bpf_fprog(optval);
4103                 if (!optval)
4104                         return -EFAULT;
4105                 optlen = sizeof(struct sock_fprog);
4106         }
4107
4108         return packet_setsockopt(sock, level, optname, optval, optlen);
4109 }
4110 #endif
4111
4112 static int packet_notifier(struct notifier_block *this,
4113                            unsigned long msg, void *ptr)
4114 {
4115         struct sock *sk;
4116         struct net_device *dev = netdev_notifier_info_to_dev(ptr);
4117         struct net *net = dev_net(dev);
4118
4119         rcu_read_lock();
4120         sk_for_each_rcu(sk, &net->packet.sklist) {
4121                 struct packet_sock *po = pkt_sk(sk);
4122
4123                 switch (msg) {
4124                 case NETDEV_UNREGISTER:
4125                         if (po->mclist)
4126                                 packet_dev_mclist_delete(dev, &po->mclist);
4127                         /* fallthrough */
4128
4129                 case NETDEV_DOWN:
4130                         if (dev->ifindex == po->ifindex) {
4131                                 spin_lock(&po->bind_lock);
4132                                 if (po->running) {
4133                                         __unregister_prot_hook(sk, false);
4134                                         sk->sk_err = ENETDOWN;
4135                                         if (!sock_flag(sk, SOCK_DEAD))
4136                                                 sk->sk_error_report(sk);
4137                                 }
4138                                 if (msg == NETDEV_UNREGISTER) {
4139                                         packet_cached_dev_reset(po);
4140                                         WRITE_ONCE(po->ifindex, -1);
4141                                         if (po->prot_hook.dev)
4142                                                 dev_put(po->prot_hook.dev);
4143                                         po->prot_hook.dev = NULL;
4144                                 }
4145                                 spin_unlock(&po->bind_lock);
4146                         }
4147                         break;
4148                 case NETDEV_UP:
4149                         if (dev->ifindex == po->ifindex) {
4150                                 spin_lock(&po->bind_lock);
4151                                 if (po->num)
4152                                         register_prot_hook(sk);
4153                                 spin_unlock(&po->bind_lock);
4154                         }
4155                         break;
4156                 }
4157         }
4158         rcu_read_unlock();
4159         return NOTIFY_DONE;
4160 }
4161
4162
4163 static int packet_ioctl(struct socket *sock, unsigned int cmd,
4164                         unsigned long arg)
4165 {
4166         struct sock *sk = sock->sk;
4167
4168         switch (cmd) {
4169         case SIOCOUTQ:
4170         {
4171                 int amount = sk_wmem_alloc_get(sk);
4172
4173                 return put_user(amount, (int __user *)arg);
4174         }
4175         case SIOCINQ:
4176         {
4177                 struct sk_buff *skb;
4178                 int amount = 0;
4179
4180                 spin_lock_bh(&sk->sk_receive_queue.lock);
4181                 skb = skb_peek(&sk->sk_receive_queue);
4182                 if (skb)
4183                         amount = skb->len;
4184                 spin_unlock_bh(&sk->sk_receive_queue.lock);
4185                 return put_user(amount, (int __user *)arg);
4186         }
4187         case SIOCGSTAMP:
4188                 return sock_get_timestamp(sk, (struct timeval __user *)arg);
4189         case SIOCGSTAMPNS:
4190                 return sock_get_timestampns(sk, (struct timespec __user *)arg);
4191
4192 #ifdef CONFIG_INET
4193         case SIOCADDRT:
4194         case SIOCDELRT:
4195         case SIOCDARP:
4196         case SIOCGARP:
4197         case SIOCSARP:
4198         case SIOCGIFADDR:
4199         case SIOCSIFADDR:
4200         case SIOCGIFBRDADDR:
4201         case SIOCSIFBRDADDR:
4202         case SIOCGIFNETMASK:
4203         case SIOCSIFNETMASK:
4204         case SIOCGIFDSTADDR:
4205         case SIOCSIFDSTADDR:
4206         case SIOCSIFFLAGS:
4207                 return inet_dgram_ops.ioctl(sock, cmd, arg);
4208 #endif
4209
4210         default:
4211                 return -ENOIOCTLCMD;
4212         }
4213         return 0;
4214 }
4215
4216 static unsigned int packet_poll(struct file *file, struct socket *sock,
4217                                 poll_table *wait)
4218 {
4219         struct sock *sk = sock->sk;
4220         struct packet_sock *po = pkt_sk(sk);
4221         unsigned int mask = datagram_poll(file, sock, wait);
4222
4223         spin_lock_bh(&sk->sk_receive_queue.lock);
4224         if (po->rx_ring.pg_vec) {
4225                 if (!packet_previous_rx_frame(po, &po->rx_ring,
4226                         TP_STATUS_KERNEL))
4227                         mask |= POLLIN | POLLRDNORM;
4228         }
4229         if (po->pressure && __packet_rcv_has_room(po, NULL) == ROOM_NORMAL)
4230                 po->pressure = 0;
4231         spin_unlock_bh(&sk->sk_receive_queue.lock);
4232         spin_lock_bh(&sk->sk_write_queue.lock);
4233         if (po->tx_ring.pg_vec) {
4234                 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
4235                         mask |= POLLOUT | POLLWRNORM;
4236         }
4237         spin_unlock_bh(&sk->sk_write_queue.lock);
4238         return mask;
4239 }
4240
4241
4242 /* Dirty? Well, I still did not learn better way to account
4243  * for user mmaps.
4244  */
4245
4246 static void packet_mm_open(struct vm_area_struct *vma)
4247 {
4248         struct file *file = vma->vm_file;
4249         struct socket *sock = file->private_data;
4250         struct sock *sk = sock->sk;
4251
4252         if (sk)
4253                 atomic_inc(&pkt_sk(sk)->mapped);
4254 }
4255
4256 static void packet_mm_close(struct vm_area_struct *vma)
4257 {
4258         struct file *file = vma->vm_file;
4259         struct socket *sock = file->private_data;
4260         struct sock *sk = sock->sk;
4261
4262         if (sk)
4263                 atomic_dec(&pkt_sk(sk)->mapped);
4264 }
4265
4266 static const struct vm_operations_struct packet_mmap_ops = {
4267         .open   =       packet_mm_open,
4268         .close  =       packet_mm_close,
4269 };
4270
4271 static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
4272                         unsigned int len)
4273 {
4274         int i;
4275
4276         for (i = 0; i < len; i++) {
4277                 if (likely(pg_vec[i].buffer)) {
4278                         if (is_vmalloc_addr(pg_vec[i].buffer))
4279                                 vfree(pg_vec[i].buffer);
4280                         else
4281                                 free_pages((unsigned long)pg_vec[i].buffer,
4282                                            order);
4283                         pg_vec[i].buffer = NULL;
4284                 }
4285         }
4286         kfree(pg_vec);
4287 }
4288
4289 static char *alloc_one_pg_vec_page(unsigned long order)
4290 {
4291         char *buffer;
4292         gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
4293                           __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
4294
4295         buffer = (char *) __get_free_pages(gfp_flags, order);
4296         if (buffer)
4297                 return buffer;
4298
4299         /* __get_free_pages failed, fall back to vmalloc */
4300         buffer = vzalloc((1 << order) * PAGE_SIZE);
4301         if (buffer)
4302                 return buffer;
4303
4304         /* vmalloc failed, lets dig into swap here */
4305         gfp_flags &= ~__GFP_NORETRY;
4306         buffer = (char *) __get_free_pages(gfp_flags, order);
4307         if (buffer)
4308                 return buffer;
4309
4310         /* complete and utter failure */
4311         return NULL;
4312 }
4313
4314 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
4315 {
4316         unsigned int block_nr = req->tp_block_nr;
4317         struct pgv *pg_vec;
4318         int i;
4319
4320         pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL | __GFP_NOWARN);
4321         if (unlikely(!pg_vec))
4322                 goto out;
4323
4324         for (i = 0; i < block_nr; i++) {
4325                 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
4326                 if (unlikely(!pg_vec[i].buffer))
4327                         goto out_free_pgvec;
4328         }
4329
4330 out:
4331         return pg_vec;
4332
4333 out_free_pgvec:
4334         free_pg_vec(pg_vec, order, block_nr);
4335         pg_vec = NULL;
4336         goto out;
4337 }
4338
4339 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
4340                 int closing, int tx_ring)
4341 {
4342         struct pgv *pg_vec = NULL;
4343         struct packet_sock *po = pkt_sk(sk);
4344         unsigned long *rx_owner_map = NULL;
4345         int was_running, order = 0;
4346         struct packet_ring_buffer *rb;
4347         struct sk_buff_head *rb_queue;
4348         __be16 num;
4349         int err = -EINVAL;
4350         /* Added to avoid minimal code churn */
4351         struct tpacket_req *req = &req_u->req;
4352
4353         rb = tx_ring ? &po->tx_ring : &po->rx_ring;
4354         rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
4355
4356         err = -EBUSY;
4357         if (!closing) {
4358                 if (atomic_read(&po->mapped))
4359                         goto out;
4360                 if (packet_read_pending(rb))
4361                         goto out;
4362         }
4363
4364         if (req->tp_block_nr) {
4365                 unsigned int min_frame_size;
4366
4367                 /* Sanity tests and some calculations */
4368                 err = -EBUSY;
4369                 if (unlikely(rb->pg_vec))
4370                         goto out;
4371
4372                 switch (po->tp_version) {
4373                 case TPACKET_V1:
4374                         po->tp_hdrlen = TPACKET_HDRLEN;
4375                         break;
4376                 case TPACKET_V2:
4377                         po->tp_hdrlen = TPACKET2_HDRLEN;
4378                         break;
4379                 case TPACKET_V3:
4380                         po->tp_hdrlen = TPACKET3_HDRLEN;
4381                         break;
4382                 }
4383
4384                 err = -EINVAL;
4385                 if (unlikely((int)req->tp_block_size <= 0))
4386                         goto out;
4387                 if (unlikely(!PAGE_ALIGNED(req->tp_block_size)))
4388                         goto out;
4389                 min_frame_size = po->tp_hdrlen + po->tp_reserve;
4390                 if (po->tp_version >= TPACKET_V3 &&
4391                     req->tp_block_size <
4392                     BLK_PLUS_PRIV((u64)req_u->req3.tp_sizeof_priv) + min_frame_size)
4393                         goto out;
4394                 if (unlikely(req->tp_frame_size < min_frame_size))
4395                         goto out;
4396                 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
4397                         goto out;
4398
4399                 rb->frames_per_block = req->tp_block_size / req->tp_frame_size;
4400                 if (unlikely(rb->frames_per_block == 0))
4401                         goto out;
4402                 if (unlikely(rb->frames_per_block > UINT_MAX / req->tp_block_nr))
4403                         goto out;
4404                 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
4405                                         req->tp_frame_nr))
4406                         goto out;
4407
4408                 err = -ENOMEM;
4409                 order = get_order(req->tp_block_size);
4410                 pg_vec = alloc_pg_vec(req, order);
4411                 if (unlikely(!pg_vec))
4412                         goto out;
4413                 switch (po->tp_version) {
4414                 case TPACKET_V3:
4415                         /* Block transmit is not supported yet */
4416                         if (!tx_ring) {
4417                                 init_prb_bdqc(po, rb, pg_vec, req_u);
4418                         } else {
4419                                 struct tpacket_req3 *req3 = &req_u->req3;
4420
4421                                 if (req3->tp_retire_blk_tov ||
4422                                     req3->tp_sizeof_priv ||
4423                                     req3->tp_feature_req_word) {
4424                                         err = -EINVAL;
4425                                         goto out_free_pg_vec;
4426                                 }
4427                         }
4428                         break;
4429                 default:
4430                         if (!tx_ring) {
4431                                 rx_owner_map = bitmap_alloc(req->tp_frame_nr,
4432                                         GFP_KERNEL | __GFP_NOWARN | __GFP_ZERO);
4433                                 if (!rx_owner_map)
4434                                         goto out_free_pg_vec;
4435                         }
4436                         break;
4437                 }
4438         }
4439         /* Done */
4440         else {
4441                 err = -EINVAL;
4442                 if (unlikely(req->tp_frame_nr))
4443                         goto out;
4444         }
4445
4446
4447         /* Detach socket from network */
4448         spin_lock(&po->bind_lock);
4449         was_running = po->running;
4450         num = po->num;
4451         if (was_running) {
4452                 WRITE_ONCE(po->num, 0);
4453                 __unregister_prot_hook(sk, false);
4454         }
4455         spin_unlock(&po->bind_lock);
4456
4457         synchronize_net();
4458
4459         err = -EBUSY;
4460         mutex_lock(&po->pg_vec_lock);
4461         if (closing || atomic_read(&po->mapped) == 0) {
4462                 err = 0;
4463                 spin_lock_bh(&rb_queue->lock);
4464                 swap(rb->pg_vec, pg_vec);
4465                 if (po->tp_version <= TPACKET_V2)
4466                         swap(rb->rx_owner_map, rx_owner_map);
4467                 rb->frame_max = (req->tp_frame_nr - 1);
4468                 rb->head = 0;
4469                 rb->frame_size = req->tp_frame_size;
4470                 spin_unlock_bh(&rb_queue->lock);
4471
4472                 swap(rb->pg_vec_order, order);
4473                 swap(rb->pg_vec_len, req->tp_block_nr);
4474
4475                 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
4476                 po->prot_hook.func = (po->rx_ring.pg_vec) ?
4477                                                 tpacket_rcv : packet_rcv;
4478                 skb_queue_purge(rb_queue);
4479                 if (atomic_read(&po->mapped))
4480                         pr_err("packet_mmap: vma is busy: %d\n",
4481                                atomic_read(&po->mapped));
4482         }
4483         mutex_unlock(&po->pg_vec_lock);
4484
4485         spin_lock(&po->bind_lock);
4486         if (was_running) {
4487                 WRITE_ONCE(po->num, num);
4488                 register_prot_hook(sk);
4489         }
4490         spin_unlock(&po->bind_lock);
4491         if (pg_vec && (po->tp_version > TPACKET_V2)) {
4492                 /* Because we don't support block-based V3 on tx-ring */
4493                 if (!tx_ring)
4494                         prb_shutdown_retire_blk_timer(po, rb_queue);
4495         }
4496
4497 out_free_pg_vec:
4498         if (pg_vec) {
4499                 bitmap_free(rx_owner_map);
4500                 free_pg_vec(pg_vec, order, req->tp_block_nr);
4501         }
4502 out:
4503         return err;
4504 }
4505
4506 static int packet_mmap(struct file *file, struct socket *sock,
4507                 struct vm_area_struct *vma)
4508 {
4509         struct sock *sk = sock->sk;
4510         struct packet_sock *po = pkt_sk(sk);
4511         unsigned long size, expected_size;
4512         struct packet_ring_buffer *rb;
4513         unsigned long start;
4514         int err = -EINVAL;
4515         int i;
4516
4517         if (vma->vm_pgoff)
4518                 return -EINVAL;
4519
4520         mutex_lock(&po->pg_vec_lock);
4521
4522         expected_size = 0;
4523         for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
4524                 if (rb->pg_vec) {
4525                         expected_size += rb->pg_vec_len
4526                                                 * rb->pg_vec_pages
4527                                                 * PAGE_SIZE;
4528                 }
4529         }
4530
4531         if (expected_size == 0)
4532                 goto out;
4533
4534         size = vma->vm_end - vma->vm_start;
4535         if (size != expected_size)
4536                 goto out;
4537
4538         start = vma->vm_start;
4539         for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
4540                 if (rb->pg_vec == NULL)
4541                         continue;
4542
4543                 for (i = 0; i < rb->pg_vec_len; i++) {
4544                         struct page *page;
4545                         void *kaddr = rb->pg_vec[i].buffer;
4546                         int pg_num;
4547
4548                         for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
4549                                 page = pgv_to_page(kaddr);
4550                                 err = vm_insert_page(vma, start, page);
4551                                 if (unlikely(err))
4552                                         goto out;
4553                                 start += PAGE_SIZE;
4554                                 kaddr += PAGE_SIZE;
4555                         }
4556                 }
4557         }
4558
4559         atomic_inc(&po->mapped);
4560         vma->vm_ops = &packet_mmap_ops;
4561         err = 0;
4562
4563 out:
4564         mutex_unlock(&po->pg_vec_lock);
4565         return err;
4566 }
4567
4568 static const struct proto_ops packet_ops_spkt = {
4569         .family =       PF_PACKET,
4570         .owner =        THIS_MODULE,
4571         .release =      packet_release,
4572         .bind =         packet_bind_spkt,
4573         .connect =      sock_no_connect,
4574         .socketpair =   sock_no_socketpair,
4575         .accept =       sock_no_accept,
4576         .getname =      packet_getname_spkt,
4577         .poll =         datagram_poll,
4578         .ioctl =        packet_ioctl,
4579         .listen =       sock_no_listen,
4580         .shutdown =     sock_no_shutdown,
4581         .setsockopt =   sock_no_setsockopt,
4582         .getsockopt =   sock_no_getsockopt,
4583         .sendmsg =      packet_sendmsg_spkt,
4584         .recvmsg =      packet_recvmsg,
4585         .mmap =         sock_no_mmap,
4586         .sendpage =     sock_no_sendpage,
4587 };
4588
4589 static const struct proto_ops packet_ops = {
4590         .family =       PF_PACKET,
4591         .owner =        THIS_MODULE,
4592         .release =      packet_release,
4593         .bind =         packet_bind,
4594         .connect =      sock_no_connect,
4595         .socketpair =   sock_no_socketpair,
4596         .accept =       sock_no_accept,
4597         .getname =      packet_getname,
4598         .poll =         packet_poll,
4599         .ioctl =        packet_ioctl,
4600         .listen =       sock_no_listen,
4601         .shutdown =     sock_no_shutdown,
4602         .setsockopt =   packet_setsockopt,
4603         .getsockopt =   packet_getsockopt,
4604 #ifdef CONFIG_COMPAT
4605         .compat_setsockopt = compat_packet_setsockopt,
4606 #endif
4607         .sendmsg =      packet_sendmsg,
4608         .recvmsg =      packet_recvmsg,
4609         .mmap =         packet_mmap,
4610         .sendpage =     sock_no_sendpage,
4611 };
4612
4613 static const struct net_proto_family packet_family_ops = {
4614         .family =       PF_PACKET,
4615         .create =       packet_create,
4616         .owner  =       THIS_MODULE,
4617 };
4618
4619 static struct notifier_block packet_netdev_notifier = {
4620         .notifier_call =        packet_notifier,
4621 };
4622
4623 #ifdef CONFIG_PROC_FS
4624
4625 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
4626         __acquires(RCU)
4627 {
4628         struct net *net = seq_file_net(seq);
4629
4630         rcu_read_lock();
4631         return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
4632 }
4633
4634 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4635 {
4636         struct net *net = seq_file_net(seq);
4637         return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
4638 }
4639
4640 static void packet_seq_stop(struct seq_file *seq, void *v)
4641         __releases(RCU)
4642 {
4643         rcu_read_unlock();
4644 }
4645
4646 static int packet_seq_show(struct seq_file *seq, void *v)
4647 {
4648         if (v == SEQ_START_TOKEN)
4649                 seq_puts(seq, "sk       RefCnt Type Proto  Iface R Rmem   User   Inode\n");
4650         else {
4651                 struct sock *s = sk_entry(v);
4652                 const struct packet_sock *po = pkt_sk(s);
4653
4654                 seq_printf(seq,
4655                            "%pK %-6d %-4d %04x   %-5d %1d %-6u %-6u %-6lu\n",
4656                            s,
4657                            refcount_read(&s->sk_refcnt),
4658                            s->sk_type,
4659                            ntohs(READ_ONCE(po->num)),
4660                            READ_ONCE(po->ifindex),
4661                            po->running,
4662                            atomic_read(&s->sk_rmem_alloc),
4663                            from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)),
4664                            sock_i_ino(s));
4665         }
4666
4667         return 0;
4668 }
4669
4670 static const struct seq_operations packet_seq_ops = {
4671         .start  = packet_seq_start,
4672         .next   = packet_seq_next,
4673         .stop   = packet_seq_stop,
4674         .show   = packet_seq_show,
4675 };
4676
4677 static int packet_seq_open(struct inode *inode, struct file *file)
4678 {
4679         return seq_open_net(inode, file, &packet_seq_ops,
4680                             sizeof(struct seq_net_private));
4681 }
4682
4683 static const struct file_operations packet_seq_fops = {
4684         .owner          = THIS_MODULE,
4685         .open           = packet_seq_open,
4686         .read           = seq_read,
4687         .llseek         = seq_lseek,
4688         .release        = seq_release_net,
4689 };
4690
4691 #endif
4692
4693 static int __net_init packet_net_init(struct net *net)
4694 {
4695         mutex_init(&net->packet.sklist_lock);
4696         INIT_HLIST_HEAD(&net->packet.sklist);
4697
4698         if (!proc_create("packet", 0, net->proc_net, &packet_seq_fops))
4699                 return -ENOMEM;
4700
4701         return 0;
4702 }
4703
4704 static void __net_exit packet_net_exit(struct net *net)
4705 {
4706         remove_proc_entry("packet", net->proc_net);
4707 }
4708
4709 static struct pernet_operations packet_net_ops = {
4710         .init = packet_net_init,
4711         .exit = packet_net_exit,
4712 };
4713
4714
4715 static void __exit packet_exit(void)
4716 {
4717         unregister_netdevice_notifier(&packet_netdev_notifier);
4718         unregister_pernet_subsys(&packet_net_ops);
4719         sock_unregister(PF_PACKET);
4720         proto_unregister(&packet_proto);
4721 }
4722
4723 static int __init packet_init(void)
4724 {
4725         int rc;
4726
4727         rc = proto_register(&packet_proto, 0);
4728         if (rc)
4729                 goto out;
4730         rc = sock_register(&packet_family_ops);
4731         if (rc)
4732                 goto out_proto;
4733         rc = register_pernet_subsys(&packet_net_ops);
4734         if (rc)
4735                 goto out_sock;
4736         rc = register_netdevice_notifier(&packet_netdev_notifier);
4737         if (rc)
4738                 goto out_pernet;
4739
4740         return 0;
4741
4742 out_pernet:
4743         unregister_pernet_subsys(&packet_net_ops);
4744 out_sock:
4745         sock_unregister(PF_PACKET);
4746 out_proto:
4747         proto_unregister(&packet_proto);
4748 out:
4749         return rc;
4750 }
4751
4752 module_init(packet_init);
4753 module_exit(packet_exit);
4754 MODULE_LICENSE("GPL");
4755 MODULE_ALIAS_NETPROTO(PF_PACKET);