1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * INET An implementation of the TCP/IP protocol suite for the LINUX
4 * operating system. INET is implemented using the BSD Socket
5 * interface as the means of communication with the user level.
7 * PACKET - implements raw packet sockets.
10 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
11 * Alan Cox, <gw4pts@gw4pts.ampr.org>
14 * Alan Cox : verify_area() now used correctly
15 * Alan Cox : new skbuff lists, look ma no backlogs!
16 * Alan Cox : tidied skbuff lists.
17 * Alan Cox : Now uses generic datagram routines I
18 * added. Also fixed the peek/read crash
19 * from all old Linux datagram code.
20 * Alan Cox : Uses the improved datagram code.
21 * Alan Cox : Added NULL's for socket options.
22 * Alan Cox : Re-commented the code.
23 * Alan Cox : Use new kernel side addressing
24 * Rob Janssen : Correct MTU usage.
25 * Dave Platt : Counter leaks caused by incorrect
26 * interrupt locking and some slightly
27 * dubious gcc output. Can you read
28 * compiler: it said _VOLATILE_
29 * Richard Kooijman : Timestamp fixes.
30 * Alan Cox : New buffers. Use sk->mac.raw.
31 * Alan Cox : sendmsg/recvmsg support.
32 * Alan Cox : Protocol setting support
33 * Alexey Kuznetsov : Untied from IPv4 stack.
34 * Cyrus Durgin : Fixed kerneld for kmod.
35 * Michal Ostrowski : Module initialization cleanup.
36 * Ulises Alonso : Frame number limit removal and
37 * packet_set_ring memory leak.
38 * Eric Biederman : Allow for > 8 byte hardware addresses.
39 * The convention is that longer addresses
40 * will simply extend the hardware address
41 * byte arrays at the end of sockaddr_ll
43 * Johann Baudy : Added TX RING.
44 * Chetan Loke : Implemented TPACKET_V3 block abstraction
46 * Copyright (C) 2011, <lokec@ccs.neu.edu>
49 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
51 #include <linux/ethtool.h>
52 #include <linux/filter.h>
53 #include <linux/types.h>
55 #include <linux/capability.h>
56 #include <linux/fcntl.h>
57 #include <linux/socket.h>
59 #include <linux/inet.h>
60 #include <linux/netdevice.h>
61 #include <linux/if_packet.h>
62 #include <linux/wireless.h>
63 #include <linux/kernel.h>
64 #include <linux/kmod.h>
65 #include <linux/slab.h>
66 #include <linux/vmalloc.h>
67 #include <net/net_namespace.h>
69 #include <net/protocol.h>
70 #include <linux/skbuff.h>
72 #include <linux/errno.h>
73 #include <linux/timer.h>
74 #include <linux/uaccess.h>
75 #include <asm/ioctls.h>
77 #include <asm/cacheflush.h>
79 #include <linux/proc_fs.h>
80 #include <linux/seq_file.h>
81 #include <linux/poll.h>
82 #include <linux/module.h>
83 #include <linux/init.h>
84 #include <linux/mutex.h>
85 #include <linux/if_vlan.h>
86 #include <linux/virtio_net.h>
87 #include <linux/errqueue.h>
88 #include <linux/net_tstamp.h>
89 #include <linux/percpu.h>
91 #include <net/inet_common.h>
93 #include <linux/bpf.h>
94 #include <net/compat.h>
95 #include <linux/netfilter_netdev.h>
101 - If the device has no dev->header_ops->create, there is no LL header
102 visible above the device. In this case, its hard_header_len should be 0.
103 The device may prepend its own header internally. In this case, its
104 needed_headroom should be set to the space needed for it to add its
106 For example, a WiFi driver pretending to be an Ethernet driver should
107 set its hard_header_len to be the Ethernet header length, and set its
108 needed_headroom to be (the real WiFi header length - the fake Ethernet
110 - packet socket receives packets with pulled ll header,
111 so that SOCK_RAW should push it back.
116 Incoming, dev_has_header(dev) == true
117 mac_header -> ll header
120 Outgoing, dev_has_header(dev) == true
121 mac_header -> ll header
124 Incoming, dev_has_header(dev) == false
126 However drivers often make it point to the ll header.
127 This is incorrect because the ll header should be invisible to us.
130 Outgoing, dev_has_header(dev) == false
131 mac_header -> data. ll header is invisible to us.
135 If dev_has_header(dev) == false we are unable to restore the ll header,
136 because it is invisible to us.
142 dev_has_header(dev) == true
143 mac_header -> ll header
146 dev_has_header(dev) == false (ll header is invisible to us)
150 We should set network_header on output to the correct position,
151 packet classifier depends on it.
154 /* Private packet socket structures. */
156 /* identical to struct packet_mreq except it has
157 * a longer address field.
159 struct packet_mreq_max {
161 unsigned short mr_type;
162 unsigned short mr_alen;
163 unsigned char mr_address[MAX_ADDR_LEN];
167 struct tpacket_hdr *h1;
168 struct tpacket2_hdr *h2;
169 struct tpacket3_hdr *h3;
173 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
174 int closing, int tx_ring);
176 #define V3_ALIGNMENT (8)
178 #define BLK_HDR_LEN (ALIGN(sizeof(struct tpacket_block_desc), V3_ALIGNMENT))
180 #define BLK_PLUS_PRIV(sz_of_priv) \
181 (BLK_HDR_LEN + ALIGN((sz_of_priv), V3_ALIGNMENT))
183 #define BLOCK_STATUS(x) ((x)->hdr.bh1.block_status)
184 #define BLOCK_NUM_PKTS(x) ((x)->hdr.bh1.num_pkts)
185 #define BLOCK_O2FP(x) ((x)->hdr.bh1.offset_to_first_pkt)
186 #define BLOCK_LEN(x) ((x)->hdr.bh1.blk_len)
187 #define BLOCK_SNUM(x) ((x)->hdr.bh1.seq_num)
188 #define BLOCK_O2PRIV(x) ((x)->offset_to_priv)
191 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
192 struct packet_type *pt, struct net_device *orig_dev);
194 static void *packet_previous_frame(struct packet_sock *po,
195 struct packet_ring_buffer *rb,
197 static void packet_increment_head(struct packet_ring_buffer *buff);
198 static int prb_curr_blk_in_use(struct tpacket_block_desc *);
199 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *,
200 struct packet_sock *);
201 static void prb_retire_current_block(struct tpacket_kbdq_core *,
202 struct packet_sock *, unsigned int status);
203 static int prb_queue_frozen(struct tpacket_kbdq_core *);
204 static void prb_open_block(struct tpacket_kbdq_core *,
205 struct tpacket_block_desc *);
206 static void prb_retire_rx_blk_timer_expired(struct timer_list *);
207 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *);
208 static void prb_fill_rxhash(struct tpacket_kbdq_core *, struct tpacket3_hdr *);
209 static void prb_clear_rxhash(struct tpacket_kbdq_core *,
210 struct tpacket3_hdr *);
211 static void prb_fill_vlan_info(struct tpacket_kbdq_core *,
212 struct tpacket3_hdr *);
213 static void packet_flush_mclist(struct sock *sk);
214 static u16 packet_pick_tx_queue(struct sk_buff *skb);
216 struct packet_skb_cb {
218 struct sockaddr_pkt pkt;
220 /* Trick: alias skb original length with
221 * ll.sll_family and ll.protocol in order
224 unsigned int origlen;
225 struct sockaddr_ll ll;
230 #define vio_le() virtio_legacy_is_little_endian()
232 #define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
234 #define GET_PBDQC_FROM_RB(x) ((struct tpacket_kbdq_core *)(&(x)->prb_bdqc))
235 #define GET_PBLOCK_DESC(x, bid) \
236 ((struct tpacket_block_desc *)((x)->pkbdq[(bid)].buffer))
237 #define GET_CURR_PBLOCK_DESC_FROM_CORE(x) \
238 ((struct tpacket_block_desc *)((x)->pkbdq[(x)->kactive_blk_num].buffer))
239 #define GET_NEXT_PRB_BLK_NUM(x) \
240 (((x)->kactive_blk_num < ((x)->knum_blocks-1)) ? \
241 ((x)->kactive_blk_num+1) : 0)
243 static void __fanout_unlink(struct sock *sk, struct packet_sock *po);
244 static void __fanout_link(struct sock *sk, struct packet_sock *po);
246 #ifdef CONFIG_NETFILTER_EGRESS
247 static noinline struct sk_buff *nf_hook_direct_egress(struct sk_buff *skb)
249 struct sk_buff *next, *head = NULL, *tail;
253 for (; skb != NULL; skb = next) {
255 skb_mark_not_on_list(skb);
257 if (!nf_hook_egress(skb, &rc, skb->dev))
273 static int packet_xmit(const struct packet_sock *po, struct sk_buff *skb)
275 if (!packet_sock_flag(po, PACKET_SOCK_QDISC_BYPASS))
276 return dev_queue_xmit(skb);
278 #ifdef CONFIG_NETFILTER_EGRESS
279 if (nf_hook_egress_active()) {
280 skb = nf_hook_direct_egress(skb);
282 return NET_XMIT_DROP;
285 return dev_direct_xmit(skb, packet_pick_tx_queue(skb));
288 static struct net_device *packet_cached_dev_get(struct packet_sock *po)
290 struct net_device *dev;
293 dev = rcu_dereference(po->cached_dev);
300 static void packet_cached_dev_assign(struct packet_sock *po,
301 struct net_device *dev)
303 rcu_assign_pointer(po->cached_dev, dev);
306 static void packet_cached_dev_reset(struct packet_sock *po)
308 RCU_INIT_POINTER(po->cached_dev, NULL);
311 static u16 packet_pick_tx_queue(struct sk_buff *skb)
313 struct net_device *dev = skb->dev;
314 const struct net_device_ops *ops = dev->netdev_ops;
315 int cpu = raw_smp_processor_id();
319 skb->sender_cpu = cpu + 1;
321 skb_record_rx_queue(skb, cpu % dev->real_num_tx_queues);
322 if (ops->ndo_select_queue) {
323 queue_index = ops->ndo_select_queue(dev, skb, NULL);
324 queue_index = netdev_cap_txqueue(dev, queue_index);
326 queue_index = netdev_pick_tx(dev, skb, NULL);
332 /* __register_prot_hook must be invoked through register_prot_hook
333 * or from a context in which asynchronous accesses to the packet
334 * socket is not possible (packet_create()).
336 static void __register_prot_hook(struct sock *sk)
338 struct packet_sock *po = pkt_sk(sk);
340 if (!packet_sock_flag(po, PACKET_SOCK_RUNNING)) {
342 __fanout_link(sk, po);
344 dev_add_pack(&po->prot_hook);
347 packet_sock_flag_set(po, PACKET_SOCK_RUNNING, 1);
351 static void register_prot_hook(struct sock *sk)
353 lockdep_assert_held_once(&pkt_sk(sk)->bind_lock);
354 __register_prot_hook(sk);
357 /* If the sync parameter is true, we will temporarily drop
358 * the po->bind_lock and do a synchronize_net to make sure no
359 * asynchronous packet processing paths still refer to the elements
360 * of po->prot_hook. If the sync parameter is false, it is the
361 * callers responsibility to take care of this.
363 static void __unregister_prot_hook(struct sock *sk, bool sync)
365 struct packet_sock *po = pkt_sk(sk);
367 lockdep_assert_held_once(&po->bind_lock);
369 packet_sock_flag_set(po, PACKET_SOCK_RUNNING, 0);
372 __fanout_unlink(sk, po);
374 __dev_remove_pack(&po->prot_hook);
379 spin_unlock(&po->bind_lock);
381 spin_lock(&po->bind_lock);
385 static void unregister_prot_hook(struct sock *sk, bool sync)
387 struct packet_sock *po = pkt_sk(sk);
389 if (packet_sock_flag(po, PACKET_SOCK_RUNNING))
390 __unregister_prot_hook(sk, sync);
393 static inline struct page * __pure pgv_to_page(void *addr)
395 if (is_vmalloc_addr(addr))
396 return vmalloc_to_page(addr);
397 return virt_to_page(addr);
400 static void __packet_set_status(struct packet_sock *po, void *frame, int status)
402 union tpacket_uhdr h;
404 /* WRITE_ONCE() are paired with READ_ONCE() in __packet_get_status */
407 switch (po->tp_version) {
409 WRITE_ONCE(h.h1->tp_status, status);
410 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
413 WRITE_ONCE(h.h2->tp_status, status);
414 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
417 WRITE_ONCE(h.h3->tp_status, status);
418 flush_dcache_page(pgv_to_page(&h.h3->tp_status));
421 WARN(1, "TPACKET version not supported.\n");
428 static int __packet_get_status(const struct packet_sock *po, void *frame)
430 union tpacket_uhdr h;
434 /* READ_ONCE() are paired with WRITE_ONCE() in __packet_set_status */
437 switch (po->tp_version) {
439 flush_dcache_page(pgv_to_page(&h.h1->tp_status));
440 return READ_ONCE(h.h1->tp_status);
442 flush_dcache_page(pgv_to_page(&h.h2->tp_status));
443 return READ_ONCE(h.h2->tp_status);
445 flush_dcache_page(pgv_to_page(&h.h3->tp_status));
446 return READ_ONCE(h.h3->tp_status);
448 WARN(1, "TPACKET version not supported.\n");
454 static __u32 tpacket_get_timestamp(struct sk_buff *skb, struct timespec64 *ts,
457 struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
460 (flags & SOF_TIMESTAMPING_RAW_HARDWARE) &&
461 ktime_to_timespec64_cond(shhwtstamps->hwtstamp, ts))
462 return TP_STATUS_TS_RAW_HARDWARE;
464 if ((flags & SOF_TIMESTAMPING_SOFTWARE) &&
465 ktime_to_timespec64_cond(skb_tstamp(skb), ts))
466 return TP_STATUS_TS_SOFTWARE;
471 static __u32 __packet_set_timestamp(struct packet_sock *po, void *frame,
474 union tpacket_uhdr h;
475 struct timespec64 ts;
478 if (!(ts_status = tpacket_get_timestamp(skb, &ts, READ_ONCE(po->tp_tstamp))))
483 * versions 1 through 3 overflow the timestamps in y2106, since they
484 * all store the seconds in a 32-bit unsigned integer.
485 * If we create a version 4, that should have a 64-bit timestamp,
486 * either 64-bit seconds + 32-bit nanoseconds, or just 64-bit
489 switch (po->tp_version) {
491 h.h1->tp_sec = ts.tv_sec;
492 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
495 h.h2->tp_sec = ts.tv_sec;
496 h.h2->tp_nsec = ts.tv_nsec;
499 h.h3->tp_sec = ts.tv_sec;
500 h.h3->tp_nsec = ts.tv_nsec;
503 WARN(1, "TPACKET version not supported.\n");
507 /* one flush is safe, as both fields always lie on the same cacheline */
508 flush_dcache_page(pgv_to_page(&h.h1->tp_sec));
514 static void *packet_lookup_frame(const struct packet_sock *po,
515 const struct packet_ring_buffer *rb,
516 unsigned int position,
519 unsigned int pg_vec_pos, frame_offset;
520 union tpacket_uhdr h;
522 pg_vec_pos = position / rb->frames_per_block;
523 frame_offset = position % rb->frames_per_block;
525 h.raw = rb->pg_vec[pg_vec_pos].buffer +
526 (frame_offset * rb->frame_size);
528 if (status != __packet_get_status(po, h.raw))
534 static void *packet_current_frame(struct packet_sock *po,
535 struct packet_ring_buffer *rb,
538 return packet_lookup_frame(po, rb, rb->head, status);
541 static void prb_del_retire_blk_timer(struct tpacket_kbdq_core *pkc)
543 del_timer_sync(&pkc->retire_blk_timer);
546 static void prb_shutdown_retire_blk_timer(struct packet_sock *po,
547 struct sk_buff_head *rb_queue)
549 struct tpacket_kbdq_core *pkc;
551 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
553 spin_lock_bh(&rb_queue->lock);
554 pkc->delete_blk_timer = 1;
555 spin_unlock_bh(&rb_queue->lock);
557 prb_del_retire_blk_timer(pkc);
560 static void prb_setup_retire_blk_timer(struct packet_sock *po)
562 struct tpacket_kbdq_core *pkc;
564 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
565 timer_setup(&pkc->retire_blk_timer, prb_retire_rx_blk_timer_expired,
567 pkc->retire_blk_timer.expires = jiffies;
570 static int prb_calc_retire_blk_tmo(struct packet_sock *po,
571 int blk_size_in_bytes)
573 struct net_device *dev;
574 unsigned int mbits, div;
575 struct ethtool_link_ksettings ecmd;
579 dev = __dev_get_by_index(sock_net(&po->sk), po->ifindex);
580 if (unlikely(!dev)) {
582 return DEFAULT_PRB_RETIRE_TOV;
584 err = __ethtool_get_link_ksettings(dev, &ecmd);
587 return DEFAULT_PRB_RETIRE_TOV;
589 /* If the link speed is so slow you don't really
590 * need to worry about perf anyways
592 if (ecmd.base.speed < SPEED_1000 ||
593 ecmd.base.speed == SPEED_UNKNOWN)
594 return DEFAULT_PRB_RETIRE_TOV;
596 div = ecmd.base.speed / 1000;
597 mbits = (blk_size_in_bytes * 8) / (1024 * 1024);
607 static void prb_init_ft_ops(struct tpacket_kbdq_core *p1,
608 union tpacket_req_u *req_u)
610 p1->feature_req_word = req_u->req3.tp_feature_req_word;
613 static void init_prb_bdqc(struct packet_sock *po,
614 struct packet_ring_buffer *rb,
616 union tpacket_req_u *req_u)
618 struct tpacket_kbdq_core *p1 = GET_PBDQC_FROM_RB(rb);
619 struct tpacket_block_desc *pbd;
621 memset(p1, 0x0, sizeof(*p1));
623 p1->knxt_seq_num = 1;
625 pbd = (struct tpacket_block_desc *)pg_vec[0].buffer;
626 p1->pkblk_start = pg_vec[0].buffer;
627 p1->kblk_size = req_u->req3.tp_block_size;
628 p1->knum_blocks = req_u->req3.tp_block_nr;
629 p1->hdrlen = po->tp_hdrlen;
630 p1->version = po->tp_version;
631 p1->last_kactive_blk_num = 0;
632 po->stats.stats3.tp_freeze_q_cnt = 0;
633 if (req_u->req3.tp_retire_blk_tov)
634 p1->retire_blk_tov = req_u->req3.tp_retire_blk_tov;
636 p1->retire_blk_tov = prb_calc_retire_blk_tmo(po,
637 req_u->req3.tp_block_size);
638 p1->tov_in_jiffies = msecs_to_jiffies(p1->retire_blk_tov);
639 p1->blk_sizeof_priv = req_u->req3.tp_sizeof_priv;
640 rwlock_init(&p1->blk_fill_in_prog_lock);
642 p1->max_frame_len = p1->kblk_size - BLK_PLUS_PRIV(p1->blk_sizeof_priv);
643 prb_init_ft_ops(p1, req_u);
644 prb_setup_retire_blk_timer(po);
645 prb_open_block(p1, pbd);
648 /* Do NOT update the last_blk_num first.
649 * Assumes sk_buff_head lock is held.
651 static void _prb_refresh_rx_retire_blk_timer(struct tpacket_kbdq_core *pkc)
653 mod_timer(&pkc->retire_blk_timer,
654 jiffies + pkc->tov_in_jiffies);
655 pkc->last_kactive_blk_num = pkc->kactive_blk_num;
660 * 1) We refresh the timer only when we open a block.
661 * By doing this we don't waste cycles refreshing the timer
662 * on packet-by-packet basis.
664 * With a 1MB block-size, on a 1Gbps line, it will take
665 * i) ~8 ms to fill a block + ii) memcpy etc.
666 * In this cut we are not accounting for the memcpy time.
668 * So, if the user sets the 'tmo' to 10ms then the timer
669 * will never fire while the block is still getting filled
670 * (which is what we want). However, the user could choose
671 * to close a block early and that's fine.
673 * But when the timer does fire, we check whether or not to refresh it.
674 * Since the tmo granularity is in msecs, it is not too expensive
675 * to refresh the timer, lets say every '8' msecs.
676 * Either the user can set the 'tmo' or we can derive it based on
677 * a) line-speed and b) block-size.
678 * prb_calc_retire_blk_tmo() calculates the tmo.
681 static void prb_retire_rx_blk_timer_expired(struct timer_list *t)
683 struct packet_sock *po =
684 from_timer(po, t, rx_ring.prb_bdqc.retire_blk_timer);
685 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
687 struct tpacket_block_desc *pbd;
689 spin_lock(&po->sk.sk_receive_queue.lock);
691 frozen = prb_queue_frozen(pkc);
692 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
694 if (unlikely(pkc->delete_blk_timer))
697 /* We only need to plug the race when the block is partially filled.
699 * lock(); increment BLOCK_NUM_PKTS; unlock()
700 * copy_bits() is in progress ...
701 * timer fires on other cpu:
702 * we can't retire the current block because copy_bits
706 if (BLOCK_NUM_PKTS(pbd)) {
707 /* Waiting for skb_copy_bits to finish... */
708 write_lock(&pkc->blk_fill_in_prog_lock);
709 write_unlock(&pkc->blk_fill_in_prog_lock);
712 if (pkc->last_kactive_blk_num == pkc->kactive_blk_num) {
714 if (!BLOCK_NUM_PKTS(pbd)) {
715 /* An empty block. Just refresh the timer. */
718 prb_retire_current_block(pkc, po, TP_STATUS_BLK_TMO);
719 if (!prb_dispatch_next_block(pkc, po))
724 /* Case 1. Queue was frozen because user-space was
727 if (prb_curr_blk_in_use(pbd)) {
729 * Ok, user-space is still behind.
730 * So just refresh the timer.
734 /* Case 2. queue was frozen,user-space caught up,
735 * now the link went idle && the timer fired.
736 * We don't have a block to close.So we open this
737 * block and restart the timer.
738 * opening a block thaws the queue,restarts timer
739 * Thawing/timer-refresh is a side effect.
741 prb_open_block(pkc, pbd);
748 _prb_refresh_rx_retire_blk_timer(pkc);
751 spin_unlock(&po->sk.sk_receive_queue.lock);
754 static void prb_flush_block(struct tpacket_kbdq_core *pkc1,
755 struct tpacket_block_desc *pbd1, __u32 status)
757 /* Flush everything minus the block header */
759 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
764 /* Skip the block header(we know header WILL fit in 4K) */
767 end = (u8 *)PAGE_ALIGN((unsigned long)pkc1->pkblk_end);
768 for (; start < end; start += PAGE_SIZE)
769 flush_dcache_page(pgv_to_page(start));
774 /* Now update the block status. */
776 BLOCK_STATUS(pbd1) = status;
778 /* Flush the block header */
780 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
782 flush_dcache_page(pgv_to_page(start));
792 * 2) Increment active_blk_num
794 * Note:We DONT refresh the timer on purpose.
795 * Because almost always the next block will be opened.
797 static void prb_close_block(struct tpacket_kbdq_core *pkc1,
798 struct tpacket_block_desc *pbd1,
799 struct packet_sock *po, unsigned int stat)
801 __u32 status = TP_STATUS_USER | stat;
803 struct tpacket3_hdr *last_pkt;
804 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
805 struct sock *sk = &po->sk;
807 if (atomic_read(&po->tp_drops))
808 status |= TP_STATUS_LOSING;
810 last_pkt = (struct tpacket3_hdr *)pkc1->prev;
811 last_pkt->tp_next_offset = 0;
813 /* Get the ts of the last pkt */
814 if (BLOCK_NUM_PKTS(pbd1)) {
815 h1->ts_last_pkt.ts_sec = last_pkt->tp_sec;
816 h1->ts_last_pkt.ts_nsec = last_pkt->tp_nsec;
818 /* Ok, we tmo'd - so get the current time.
820 * It shouldn't really happen as we don't close empty
821 * blocks. See prb_retire_rx_blk_timer_expired().
823 struct timespec64 ts;
824 ktime_get_real_ts64(&ts);
825 h1->ts_last_pkt.ts_sec = ts.tv_sec;
826 h1->ts_last_pkt.ts_nsec = ts.tv_nsec;
831 /* Flush the block */
832 prb_flush_block(pkc1, pbd1, status);
834 sk->sk_data_ready(sk);
836 pkc1->kactive_blk_num = GET_NEXT_PRB_BLK_NUM(pkc1);
839 static void prb_thaw_queue(struct tpacket_kbdq_core *pkc)
841 pkc->reset_pending_on_curr_blk = 0;
845 * Side effect of opening a block:
847 * 1) prb_queue is thawed.
848 * 2) retire_blk_timer is refreshed.
851 static void prb_open_block(struct tpacket_kbdq_core *pkc1,
852 struct tpacket_block_desc *pbd1)
854 struct timespec64 ts;
855 struct tpacket_hdr_v1 *h1 = &pbd1->hdr.bh1;
859 /* We could have just memset this but we will lose the
860 * flexibility of making the priv area sticky
863 BLOCK_SNUM(pbd1) = pkc1->knxt_seq_num++;
864 BLOCK_NUM_PKTS(pbd1) = 0;
865 BLOCK_LEN(pbd1) = BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
867 ktime_get_real_ts64(&ts);
869 h1->ts_first_pkt.ts_sec = ts.tv_sec;
870 h1->ts_first_pkt.ts_nsec = ts.tv_nsec;
872 pkc1->pkblk_start = (char *)pbd1;
873 pkc1->nxt_offset = pkc1->pkblk_start + BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
875 BLOCK_O2FP(pbd1) = (__u32)BLK_PLUS_PRIV(pkc1->blk_sizeof_priv);
876 BLOCK_O2PRIV(pbd1) = BLK_HDR_LEN;
878 pbd1->version = pkc1->version;
879 pkc1->prev = pkc1->nxt_offset;
880 pkc1->pkblk_end = pkc1->pkblk_start + pkc1->kblk_size;
882 prb_thaw_queue(pkc1);
883 _prb_refresh_rx_retire_blk_timer(pkc1);
889 * Queue freeze logic:
890 * 1) Assume tp_block_nr = 8 blocks.
891 * 2) At time 't0', user opens Rx ring.
892 * 3) Some time past 't0', kernel starts filling blocks starting from 0 .. 7
893 * 4) user-space is either sleeping or processing block '0'.
894 * 5) tpacket_rcv is currently filling block '7', since there is no space left,
895 * it will close block-7,loop around and try to fill block '0'.
897 * __packet_lookup_frame_in_block
898 * prb_retire_current_block()
899 * prb_dispatch_next_block()
900 * |->(BLOCK_STATUS == USER) evaluates to true
901 * 5.1) Since block-0 is currently in-use, we just freeze the queue.
902 * 6) Now there are two cases:
903 * 6.1) Link goes idle right after the queue is frozen.
904 * But remember, the last open_block() refreshed the timer.
905 * When this timer expires,it will refresh itself so that we can
906 * re-open block-0 in near future.
907 * 6.2) Link is busy and keeps on receiving packets. This is a simple
908 * case and __packet_lookup_frame_in_block will check if block-0
909 * is free and can now be re-used.
911 static void prb_freeze_queue(struct tpacket_kbdq_core *pkc,
912 struct packet_sock *po)
914 pkc->reset_pending_on_curr_blk = 1;
915 po->stats.stats3.tp_freeze_q_cnt++;
918 #define TOTAL_PKT_LEN_INCL_ALIGN(length) (ALIGN((length), V3_ALIGNMENT))
921 * If the next block is free then we will dispatch it
922 * and return a good offset.
923 * Else, we will freeze the queue.
924 * So, caller must check the return value.
926 static void *prb_dispatch_next_block(struct tpacket_kbdq_core *pkc,
927 struct packet_sock *po)
929 struct tpacket_block_desc *pbd;
933 /* 1. Get current block num */
934 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
936 /* 2. If this block is currently in_use then freeze the queue */
937 if (TP_STATUS_USER & BLOCK_STATUS(pbd)) {
938 prb_freeze_queue(pkc, po);
944 * open this block and return the offset where the first packet
945 * needs to get stored.
947 prb_open_block(pkc, pbd);
948 return (void *)pkc->nxt_offset;
951 static void prb_retire_current_block(struct tpacket_kbdq_core *pkc,
952 struct packet_sock *po, unsigned int status)
954 struct tpacket_block_desc *pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
956 /* retire/close the current block */
957 if (likely(TP_STATUS_KERNEL == BLOCK_STATUS(pbd))) {
959 * Plug the case where copy_bits() is in progress on
960 * cpu-0 and tpacket_rcv() got invoked on cpu-1, didn't
961 * have space to copy the pkt in the current block and
962 * called prb_retire_current_block()
964 * We don't need to worry about the TMO case because
965 * the timer-handler already handled this case.
967 if (!(status & TP_STATUS_BLK_TMO)) {
968 /* Waiting for skb_copy_bits to finish... */
969 write_lock(&pkc->blk_fill_in_prog_lock);
970 write_unlock(&pkc->blk_fill_in_prog_lock);
972 prb_close_block(pkc, pbd, po, status);
977 static int prb_curr_blk_in_use(struct tpacket_block_desc *pbd)
979 return TP_STATUS_USER & BLOCK_STATUS(pbd);
982 static int prb_queue_frozen(struct tpacket_kbdq_core *pkc)
984 return pkc->reset_pending_on_curr_blk;
987 static void prb_clear_blk_fill_status(struct packet_ring_buffer *rb)
988 __releases(&pkc->blk_fill_in_prog_lock)
990 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
992 read_unlock(&pkc->blk_fill_in_prog_lock);
995 static void prb_fill_rxhash(struct tpacket_kbdq_core *pkc,
996 struct tpacket3_hdr *ppd)
998 ppd->hv1.tp_rxhash = skb_get_hash(pkc->skb);
1001 static void prb_clear_rxhash(struct tpacket_kbdq_core *pkc,
1002 struct tpacket3_hdr *ppd)
1004 ppd->hv1.tp_rxhash = 0;
1007 static void prb_fill_vlan_info(struct tpacket_kbdq_core *pkc,
1008 struct tpacket3_hdr *ppd)
1010 if (skb_vlan_tag_present(pkc->skb)) {
1011 ppd->hv1.tp_vlan_tci = skb_vlan_tag_get(pkc->skb);
1012 ppd->hv1.tp_vlan_tpid = ntohs(pkc->skb->vlan_proto);
1013 ppd->tp_status = TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
1015 ppd->hv1.tp_vlan_tci = 0;
1016 ppd->hv1.tp_vlan_tpid = 0;
1017 ppd->tp_status = TP_STATUS_AVAILABLE;
1021 static void prb_run_all_ft_ops(struct tpacket_kbdq_core *pkc,
1022 struct tpacket3_hdr *ppd)
1024 ppd->hv1.tp_padding = 0;
1025 prb_fill_vlan_info(pkc, ppd);
1027 if (pkc->feature_req_word & TP_FT_REQ_FILL_RXHASH)
1028 prb_fill_rxhash(pkc, ppd);
1030 prb_clear_rxhash(pkc, ppd);
1033 static void prb_fill_curr_block(char *curr,
1034 struct tpacket_kbdq_core *pkc,
1035 struct tpacket_block_desc *pbd,
1037 __acquires(&pkc->blk_fill_in_prog_lock)
1039 struct tpacket3_hdr *ppd;
1041 ppd = (struct tpacket3_hdr *)curr;
1042 ppd->tp_next_offset = TOTAL_PKT_LEN_INCL_ALIGN(len);
1044 pkc->nxt_offset += TOTAL_PKT_LEN_INCL_ALIGN(len);
1045 BLOCK_LEN(pbd) += TOTAL_PKT_LEN_INCL_ALIGN(len);
1046 BLOCK_NUM_PKTS(pbd) += 1;
1047 read_lock(&pkc->blk_fill_in_prog_lock);
1048 prb_run_all_ft_ops(pkc, ppd);
1051 /* Assumes caller has the sk->rx_queue.lock */
1052 static void *__packet_lookup_frame_in_block(struct packet_sock *po,
1053 struct sk_buff *skb,
1057 struct tpacket_kbdq_core *pkc;
1058 struct tpacket_block_desc *pbd;
1061 pkc = GET_PBDQC_FROM_RB(&po->rx_ring);
1062 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1064 /* Queue is frozen when user space is lagging behind */
1065 if (prb_queue_frozen(pkc)) {
1067 * Check if that last block which caused the queue to freeze,
1068 * is still in_use by user-space.
1070 if (prb_curr_blk_in_use(pbd)) {
1071 /* Can't record this packet */
1075 * Ok, the block was released by user-space.
1076 * Now let's open that block.
1077 * opening a block also thaws the queue.
1078 * Thawing is a side effect.
1080 prb_open_block(pkc, pbd);
1085 curr = pkc->nxt_offset;
1087 end = (char *)pbd + pkc->kblk_size;
1089 /* first try the current block */
1090 if (curr+TOTAL_PKT_LEN_INCL_ALIGN(len) < end) {
1091 prb_fill_curr_block(curr, pkc, pbd, len);
1092 return (void *)curr;
1095 /* Ok, close the current block */
1096 prb_retire_current_block(pkc, po, 0);
1098 /* Now, try to dispatch the next block */
1099 curr = (char *)prb_dispatch_next_block(pkc, po);
1101 pbd = GET_CURR_PBLOCK_DESC_FROM_CORE(pkc);
1102 prb_fill_curr_block(curr, pkc, pbd, len);
1103 return (void *)curr;
1107 * No free blocks are available.user_space hasn't caught up yet.
1108 * Queue was just frozen and now this packet will get dropped.
1113 static void *packet_current_rx_frame(struct packet_sock *po,
1114 struct sk_buff *skb,
1115 int status, unsigned int len)
1118 switch (po->tp_version) {
1121 curr = packet_lookup_frame(po, &po->rx_ring,
1122 po->rx_ring.head, status);
1125 return __packet_lookup_frame_in_block(po, skb, len);
1127 WARN(1, "TPACKET version not supported\n");
1133 static void *prb_lookup_block(const struct packet_sock *po,
1134 const struct packet_ring_buffer *rb,
1138 struct tpacket_kbdq_core *pkc = GET_PBDQC_FROM_RB(rb);
1139 struct tpacket_block_desc *pbd = GET_PBLOCK_DESC(pkc, idx);
1141 if (status != BLOCK_STATUS(pbd))
1146 static int prb_previous_blk_num(struct packet_ring_buffer *rb)
1149 if (rb->prb_bdqc.kactive_blk_num)
1150 prev = rb->prb_bdqc.kactive_blk_num-1;
1152 prev = rb->prb_bdqc.knum_blocks-1;
1156 /* Assumes caller has held the rx_queue.lock */
1157 static void *__prb_previous_block(struct packet_sock *po,
1158 struct packet_ring_buffer *rb,
1161 unsigned int previous = prb_previous_blk_num(rb);
1162 return prb_lookup_block(po, rb, previous, status);
1165 static void *packet_previous_rx_frame(struct packet_sock *po,
1166 struct packet_ring_buffer *rb,
1169 if (po->tp_version <= TPACKET_V2)
1170 return packet_previous_frame(po, rb, status);
1172 return __prb_previous_block(po, rb, status);
1175 static void packet_increment_rx_head(struct packet_sock *po,
1176 struct packet_ring_buffer *rb)
1178 switch (po->tp_version) {
1181 return packet_increment_head(rb);
1184 WARN(1, "TPACKET version not supported.\n");
1190 static void *packet_previous_frame(struct packet_sock *po,
1191 struct packet_ring_buffer *rb,
1194 unsigned int previous = rb->head ? rb->head - 1 : rb->frame_max;
1195 return packet_lookup_frame(po, rb, previous, status);
1198 static void packet_increment_head(struct packet_ring_buffer *buff)
1200 buff->head = buff->head != buff->frame_max ? buff->head+1 : 0;
1203 static void packet_inc_pending(struct packet_ring_buffer *rb)
1205 this_cpu_inc(*rb->pending_refcnt);
1208 static void packet_dec_pending(struct packet_ring_buffer *rb)
1210 this_cpu_dec(*rb->pending_refcnt);
1213 static unsigned int packet_read_pending(const struct packet_ring_buffer *rb)
1215 unsigned int refcnt = 0;
1218 /* We don't use pending refcount in rx_ring. */
1219 if (rb->pending_refcnt == NULL)
1222 for_each_possible_cpu(cpu)
1223 refcnt += *per_cpu_ptr(rb->pending_refcnt, cpu);
1228 static int packet_alloc_pending(struct packet_sock *po)
1230 po->rx_ring.pending_refcnt = NULL;
1232 po->tx_ring.pending_refcnt = alloc_percpu(unsigned int);
1233 if (unlikely(po->tx_ring.pending_refcnt == NULL))
1239 static void packet_free_pending(struct packet_sock *po)
1241 free_percpu(po->tx_ring.pending_refcnt);
1244 #define ROOM_POW_OFF 2
1245 #define ROOM_NONE 0x0
1246 #define ROOM_LOW 0x1
1247 #define ROOM_NORMAL 0x2
1249 static bool __tpacket_has_room(const struct packet_sock *po, int pow_off)
1253 len = READ_ONCE(po->rx_ring.frame_max) + 1;
1254 idx = READ_ONCE(po->rx_ring.head);
1256 idx += len >> pow_off;
1259 return packet_lookup_frame(po, &po->rx_ring, idx, TP_STATUS_KERNEL);
1262 static bool __tpacket_v3_has_room(const struct packet_sock *po, int pow_off)
1266 len = READ_ONCE(po->rx_ring.prb_bdqc.knum_blocks);
1267 idx = READ_ONCE(po->rx_ring.prb_bdqc.kactive_blk_num);
1269 idx += len >> pow_off;
1272 return prb_lookup_block(po, &po->rx_ring, idx, TP_STATUS_KERNEL);
1275 static int __packet_rcv_has_room(const struct packet_sock *po,
1276 const struct sk_buff *skb)
1278 const struct sock *sk = &po->sk;
1279 int ret = ROOM_NONE;
1281 if (po->prot_hook.func != tpacket_rcv) {
1282 int rcvbuf = READ_ONCE(sk->sk_rcvbuf);
1283 int avail = rcvbuf - atomic_read(&sk->sk_rmem_alloc)
1284 - (skb ? skb->truesize : 0);
1286 if (avail > (rcvbuf >> ROOM_POW_OFF))
1294 if (po->tp_version == TPACKET_V3) {
1295 if (__tpacket_v3_has_room(po, ROOM_POW_OFF))
1297 else if (__tpacket_v3_has_room(po, 0))
1300 if (__tpacket_has_room(po, ROOM_POW_OFF))
1302 else if (__tpacket_has_room(po, 0))
1309 static int packet_rcv_has_room(struct packet_sock *po, struct sk_buff *skb)
1314 ret = __packet_rcv_has_room(po, skb);
1315 pressure = ret != ROOM_NORMAL;
1317 if (packet_sock_flag(po, PACKET_SOCK_PRESSURE) != pressure)
1318 packet_sock_flag_set(po, PACKET_SOCK_PRESSURE, pressure);
1323 static void packet_rcv_try_clear_pressure(struct packet_sock *po)
1325 if (packet_sock_flag(po, PACKET_SOCK_PRESSURE) &&
1326 __packet_rcv_has_room(po, NULL) == ROOM_NORMAL)
1327 packet_sock_flag_set(po, PACKET_SOCK_PRESSURE, false);
1330 static void packet_sock_destruct(struct sock *sk)
1332 skb_queue_purge(&sk->sk_error_queue);
1334 WARN_ON(atomic_read(&sk->sk_rmem_alloc));
1335 WARN_ON(refcount_read(&sk->sk_wmem_alloc));
1337 if (!sock_flag(sk, SOCK_DEAD)) {
1338 pr_err("Attempt to release alive packet socket: %p\n", sk);
1343 static bool fanout_flow_is_huge(struct packet_sock *po, struct sk_buff *skb)
1345 u32 *history = po->rollover->history;
1349 rxhash = skb_get_hash(skb);
1350 for (i = 0; i < ROLLOVER_HLEN; i++)
1351 if (READ_ONCE(history[i]) == rxhash)
1354 victim = get_random_u32_below(ROLLOVER_HLEN);
1356 /* Avoid dirtying the cache line if possible */
1357 if (READ_ONCE(history[victim]) != rxhash)
1358 WRITE_ONCE(history[victim], rxhash);
1360 return count > (ROLLOVER_HLEN >> 1);
1363 static unsigned int fanout_demux_hash(struct packet_fanout *f,
1364 struct sk_buff *skb,
1367 return reciprocal_scale(__skb_get_hash_symmetric(skb), num);
1370 static unsigned int fanout_demux_lb(struct packet_fanout *f,
1371 struct sk_buff *skb,
1374 unsigned int val = atomic_inc_return(&f->rr_cur);
1379 static unsigned int fanout_demux_cpu(struct packet_fanout *f,
1380 struct sk_buff *skb,
1383 return smp_processor_id() % num;
1386 static unsigned int fanout_demux_rnd(struct packet_fanout *f,
1387 struct sk_buff *skb,
1390 return get_random_u32_below(num);
1393 static unsigned int fanout_demux_rollover(struct packet_fanout *f,
1394 struct sk_buff *skb,
1395 unsigned int idx, bool try_self,
1398 struct packet_sock *po, *po_next, *po_skip = NULL;
1399 unsigned int i, j, room = ROOM_NONE;
1401 po = pkt_sk(rcu_dereference(f->arr[idx]));
1404 room = packet_rcv_has_room(po, skb);
1405 if (room == ROOM_NORMAL ||
1406 (room == ROOM_LOW && !fanout_flow_is_huge(po, skb)))
1411 i = j = min_t(int, po->rollover->sock, num - 1);
1413 po_next = pkt_sk(rcu_dereference(f->arr[i]));
1414 if (po_next != po_skip &&
1415 !packet_sock_flag(po_next, PACKET_SOCK_PRESSURE) &&
1416 packet_rcv_has_room(po_next, skb) == ROOM_NORMAL) {
1418 po->rollover->sock = i;
1419 atomic_long_inc(&po->rollover->num);
1420 if (room == ROOM_LOW)
1421 atomic_long_inc(&po->rollover->num_huge);
1429 atomic_long_inc(&po->rollover->num_failed);
1433 static unsigned int fanout_demux_qm(struct packet_fanout *f,
1434 struct sk_buff *skb,
1437 return skb_get_queue_mapping(skb) % num;
1440 static unsigned int fanout_demux_bpf(struct packet_fanout *f,
1441 struct sk_buff *skb,
1444 struct bpf_prog *prog;
1445 unsigned int ret = 0;
1448 prog = rcu_dereference(f->bpf_prog);
1450 ret = bpf_prog_run_clear_cb(prog, skb) % num;
1456 static bool fanout_has_flag(struct packet_fanout *f, u16 flag)
1458 return f->flags & (flag >> 8);
1461 static int packet_rcv_fanout(struct sk_buff *skb, struct net_device *dev,
1462 struct packet_type *pt, struct net_device *orig_dev)
1464 struct packet_fanout *f = pt->af_packet_priv;
1465 unsigned int num = READ_ONCE(f->num_members);
1466 struct net *net = read_pnet(&f->net);
1467 struct packet_sock *po;
1470 if (!net_eq(dev_net(dev), net) || !num) {
1475 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_DEFRAG)) {
1476 skb = ip_check_defrag(net, skb, IP_DEFRAG_AF_PACKET);
1481 case PACKET_FANOUT_HASH:
1483 idx = fanout_demux_hash(f, skb, num);
1485 case PACKET_FANOUT_LB:
1486 idx = fanout_demux_lb(f, skb, num);
1488 case PACKET_FANOUT_CPU:
1489 idx = fanout_demux_cpu(f, skb, num);
1491 case PACKET_FANOUT_RND:
1492 idx = fanout_demux_rnd(f, skb, num);
1494 case PACKET_FANOUT_QM:
1495 idx = fanout_demux_qm(f, skb, num);
1497 case PACKET_FANOUT_ROLLOVER:
1498 idx = fanout_demux_rollover(f, skb, 0, false, num);
1500 case PACKET_FANOUT_CBPF:
1501 case PACKET_FANOUT_EBPF:
1502 idx = fanout_demux_bpf(f, skb, num);
1506 if (fanout_has_flag(f, PACKET_FANOUT_FLAG_ROLLOVER))
1507 idx = fanout_demux_rollover(f, skb, idx, true, num);
1509 po = pkt_sk(rcu_dereference(f->arr[idx]));
1510 return po->prot_hook.func(skb, dev, &po->prot_hook, orig_dev);
1513 DEFINE_MUTEX(fanout_mutex);
1514 EXPORT_SYMBOL_GPL(fanout_mutex);
1515 static LIST_HEAD(fanout_list);
1516 static u16 fanout_next_id;
1518 static void __fanout_link(struct sock *sk, struct packet_sock *po)
1520 struct packet_fanout *f = po->fanout;
1522 spin_lock(&f->lock);
1523 rcu_assign_pointer(f->arr[f->num_members], sk);
1526 if (f->num_members == 1)
1527 dev_add_pack(&f->prot_hook);
1528 spin_unlock(&f->lock);
1531 static void __fanout_unlink(struct sock *sk, struct packet_sock *po)
1533 struct packet_fanout *f = po->fanout;
1536 spin_lock(&f->lock);
1537 for (i = 0; i < f->num_members; i++) {
1538 if (rcu_dereference_protected(f->arr[i],
1539 lockdep_is_held(&f->lock)) == sk)
1542 BUG_ON(i >= f->num_members);
1543 rcu_assign_pointer(f->arr[i],
1544 rcu_dereference_protected(f->arr[f->num_members - 1],
1545 lockdep_is_held(&f->lock)));
1547 if (f->num_members == 0)
1548 __dev_remove_pack(&f->prot_hook);
1549 spin_unlock(&f->lock);
1552 static bool match_fanout_group(struct packet_type *ptype, struct sock *sk)
1554 if (sk->sk_family != PF_PACKET)
1557 return ptype->af_packet_priv == pkt_sk(sk)->fanout;
1560 static void fanout_init_data(struct packet_fanout *f)
1563 case PACKET_FANOUT_LB:
1564 atomic_set(&f->rr_cur, 0);
1566 case PACKET_FANOUT_CBPF:
1567 case PACKET_FANOUT_EBPF:
1568 RCU_INIT_POINTER(f->bpf_prog, NULL);
1573 static void __fanout_set_data_bpf(struct packet_fanout *f, struct bpf_prog *new)
1575 struct bpf_prog *old;
1577 spin_lock(&f->lock);
1578 old = rcu_dereference_protected(f->bpf_prog, lockdep_is_held(&f->lock));
1579 rcu_assign_pointer(f->bpf_prog, new);
1580 spin_unlock(&f->lock);
1584 bpf_prog_destroy(old);
1588 static int fanout_set_data_cbpf(struct packet_sock *po, sockptr_t data,
1591 struct bpf_prog *new;
1592 struct sock_fprog fprog;
1595 if (sock_flag(&po->sk, SOCK_FILTER_LOCKED))
1598 ret = copy_bpf_fprog_from_user(&fprog, data, len);
1602 ret = bpf_prog_create_from_user(&new, &fprog, NULL, false);
1606 __fanout_set_data_bpf(po->fanout, new);
1610 static int fanout_set_data_ebpf(struct packet_sock *po, sockptr_t data,
1613 struct bpf_prog *new;
1616 if (sock_flag(&po->sk, SOCK_FILTER_LOCKED))
1618 if (len != sizeof(fd))
1620 if (copy_from_sockptr(&fd, data, len))
1623 new = bpf_prog_get_type(fd, BPF_PROG_TYPE_SOCKET_FILTER);
1625 return PTR_ERR(new);
1627 __fanout_set_data_bpf(po->fanout, new);
1631 static int fanout_set_data(struct packet_sock *po, sockptr_t data,
1634 switch (po->fanout->type) {
1635 case PACKET_FANOUT_CBPF:
1636 return fanout_set_data_cbpf(po, data, len);
1637 case PACKET_FANOUT_EBPF:
1638 return fanout_set_data_ebpf(po, data, len);
1644 static void fanout_release_data(struct packet_fanout *f)
1647 case PACKET_FANOUT_CBPF:
1648 case PACKET_FANOUT_EBPF:
1649 __fanout_set_data_bpf(f, NULL);
1653 static bool __fanout_id_is_free(struct sock *sk, u16 candidate_id)
1655 struct packet_fanout *f;
1657 list_for_each_entry(f, &fanout_list, list) {
1658 if (f->id == candidate_id &&
1659 read_pnet(&f->net) == sock_net(sk)) {
1666 static bool fanout_find_new_id(struct sock *sk, u16 *new_id)
1668 u16 id = fanout_next_id;
1671 if (__fanout_id_is_free(sk, id)) {
1673 fanout_next_id = id + 1;
1678 } while (id != fanout_next_id);
1683 static int fanout_add(struct sock *sk, struct fanout_args *args)
1685 struct packet_rollover *rollover = NULL;
1686 struct packet_sock *po = pkt_sk(sk);
1687 u16 type_flags = args->type_flags;
1688 struct packet_fanout *f, *match;
1689 u8 type = type_flags & 0xff;
1690 u8 flags = type_flags >> 8;
1695 case PACKET_FANOUT_ROLLOVER:
1696 if (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)
1699 case PACKET_FANOUT_HASH:
1700 case PACKET_FANOUT_LB:
1701 case PACKET_FANOUT_CPU:
1702 case PACKET_FANOUT_RND:
1703 case PACKET_FANOUT_QM:
1704 case PACKET_FANOUT_CBPF:
1705 case PACKET_FANOUT_EBPF:
1711 mutex_lock(&fanout_mutex);
1717 if (type == PACKET_FANOUT_ROLLOVER ||
1718 (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)) {
1720 rollover = kzalloc(sizeof(*rollover), GFP_KERNEL);
1723 atomic_long_set(&rollover->num, 0);
1724 atomic_long_set(&rollover->num_huge, 0);
1725 atomic_long_set(&rollover->num_failed, 0);
1728 if (type_flags & PACKET_FANOUT_FLAG_UNIQUEID) {
1733 if (!fanout_find_new_id(sk, &id)) {
1737 /* ephemeral flag for the first socket in the group: drop it */
1738 flags &= ~(PACKET_FANOUT_FLAG_UNIQUEID >> 8);
1742 list_for_each_entry(f, &fanout_list, list) {
1744 read_pnet(&f->net) == sock_net(sk)) {
1751 if (match->flags != flags)
1753 if (args->max_num_members &&
1754 args->max_num_members != match->max_num_members)
1757 if (args->max_num_members > PACKET_FANOUT_MAX)
1759 if (!args->max_num_members)
1760 /* legacy PACKET_FANOUT_MAX */
1761 args->max_num_members = 256;
1763 match = kvzalloc(struct_size(match, arr, args->max_num_members),
1767 write_pnet(&match->net, sock_net(sk));
1770 match->flags = flags;
1771 INIT_LIST_HEAD(&match->list);
1772 spin_lock_init(&match->lock);
1773 refcount_set(&match->sk_ref, 0);
1774 fanout_init_data(match);
1775 match->prot_hook.type = po->prot_hook.type;
1776 match->prot_hook.dev = po->prot_hook.dev;
1777 match->prot_hook.func = packet_rcv_fanout;
1778 match->prot_hook.af_packet_priv = match;
1779 match->prot_hook.af_packet_net = read_pnet(&match->net);
1780 match->prot_hook.id_match = match_fanout_group;
1781 match->max_num_members = args->max_num_members;
1782 match->prot_hook.ignore_outgoing = type_flags & PACKET_FANOUT_FLAG_IGNORE_OUTGOING;
1783 list_add(&match->list, &fanout_list);
1787 spin_lock(&po->bind_lock);
1788 if (packet_sock_flag(po, PACKET_SOCK_RUNNING) &&
1789 match->type == type &&
1790 match->prot_hook.type == po->prot_hook.type &&
1791 match->prot_hook.dev == po->prot_hook.dev) {
1793 if (refcount_read(&match->sk_ref) < match->max_num_members) {
1794 __dev_remove_pack(&po->prot_hook);
1796 /* Paired with packet_setsockopt(PACKET_FANOUT_DATA) */
1797 WRITE_ONCE(po->fanout, match);
1799 po->rollover = rollover;
1801 refcount_set(&match->sk_ref, refcount_read(&match->sk_ref) + 1);
1802 __fanout_link(sk, po);
1806 spin_unlock(&po->bind_lock);
1808 if (err && !refcount_read(&match->sk_ref)) {
1809 list_del(&match->list);
1815 mutex_unlock(&fanout_mutex);
1819 /* If pkt_sk(sk)->fanout->sk_ref is zero, this function removes
1820 * pkt_sk(sk)->fanout from fanout_list and returns pkt_sk(sk)->fanout.
1821 * It is the responsibility of the caller to call fanout_release_data() and
1822 * free the returned packet_fanout (after synchronize_net())
1824 static struct packet_fanout *fanout_release(struct sock *sk)
1826 struct packet_sock *po = pkt_sk(sk);
1827 struct packet_fanout *f;
1829 mutex_lock(&fanout_mutex);
1834 if (refcount_dec_and_test(&f->sk_ref))
1839 mutex_unlock(&fanout_mutex);
1844 static bool packet_extra_vlan_len_allowed(const struct net_device *dev,
1845 struct sk_buff *skb)
1847 /* Earlier code assumed this would be a VLAN pkt, double-check
1848 * this now that we have the actual packet in hand. We can only
1849 * do this check on Ethernet devices.
1851 if (unlikely(dev->type != ARPHRD_ETHER))
1854 skb_reset_mac_header(skb);
1855 return likely(eth_hdr(skb)->h_proto == htons(ETH_P_8021Q));
1858 static const struct proto_ops packet_ops;
1860 static const struct proto_ops packet_ops_spkt;
1862 static int packet_rcv_spkt(struct sk_buff *skb, struct net_device *dev,
1863 struct packet_type *pt, struct net_device *orig_dev)
1866 struct sockaddr_pkt *spkt;
1869 * When we registered the protocol we saved the socket in the data
1870 * field for just this event.
1873 sk = pt->af_packet_priv;
1876 * Yank back the headers [hope the device set this
1877 * right or kerboom...]
1879 * Incoming packets have ll header pulled,
1882 * For outgoing ones skb->data == skb_mac_header(skb)
1883 * so that this procedure is noop.
1886 if (skb->pkt_type == PACKET_LOOPBACK)
1889 if (!net_eq(dev_net(dev), sock_net(sk)))
1892 skb = skb_share_check(skb, GFP_ATOMIC);
1896 /* drop any routing info */
1899 /* drop conntrack reference */
1902 spkt = &PACKET_SKB_CB(skb)->sa.pkt;
1904 skb_push(skb, skb->data - skb_mac_header(skb));
1907 * The SOCK_PACKET socket receives _all_ frames.
1910 spkt->spkt_family = dev->type;
1911 strscpy(spkt->spkt_device, dev->name, sizeof(spkt->spkt_device));
1912 spkt->spkt_protocol = skb->protocol;
1915 * Charge the memory to the socket. This is done specifically
1916 * to prevent sockets using all the memory up.
1919 if (sock_queue_rcv_skb(sk, skb) == 0)
1928 static void packet_parse_headers(struct sk_buff *skb, struct socket *sock)
1932 if ((!skb->protocol || skb->protocol == htons(ETH_P_ALL)) &&
1933 sock->type == SOCK_RAW) {
1934 skb_reset_mac_header(skb);
1935 skb->protocol = dev_parse_header_protocol(skb);
1938 /* Move network header to the right position for VLAN tagged packets */
1939 if (likely(skb->dev->type == ARPHRD_ETHER) &&
1940 eth_type_vlan(skb->protocol) &&
1941 vlan_get_protocol_and_depth(skb, skb->protocol, &depth) != 0)
1942 skb_set_network_header(skb, depth);
1944 skb_probe_transport_header(skb);
1948 * Output a raw packet to a device layer. This bypasses all the other
1949 * protocol layers and you must therefore supply it with a complete frame
1952 static int packet_sendmsg_spkt(struct socket *sock, struct msghdr *msg,
1955 struct sock *sk = sock->sk;
1956 DECLARE_SOCKADDR(struct sockaddr_pkt *, saddr, msg->msg_name);
1957 struct sk_buff *skb = NULL;
1958 struct net_device *dev;
1959 struct sockcm_cookie sockc;
1965 * Get and verify the address.
1969 if (msg->msg_namelen < sizeof(struct sockaddr))
1971 if (msg->msg_namelen == sizeof(struct sockaddr_pkt))
1972 proto = saddr->spkt_protocol;
1974 return -ENOTCONN; /* SOCK_PACKET must be sent giving an address */
1977 * Find the device first to size check it
1980 saddr->spkt_device[sizeof(saddr->spkt_device) - 1] = 0;
1983 dev = dev_get_by_name_rcu(sock_net(sk), saddr->spkt_device);
1989 if (!(dev->flags & IFF_UP))
1993 * You may not queue a frame bigger than the mtu. This is the lowest level
1994 * raw protocol and you must do your own fragmentation at this level.
1997 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
1998 if (!netif_supports_nofcs(dev)) {
1999 err = -EPROTONOSUPPORT;
2002 extra_len = 4; /* We're doing our own CRC */
2006 if (len > dev->mtu + dev->hard_header_len + VLAN_HLEN + extra_len)
2010 size_t reserved = LL_RESERVED_SPACE(dev);
2011 int tlen = dev->needed_tailroom;
2012 unsigned int hhlen = dev->header_ops ? dev->hard_header_len : 0;
2015 skb = sock_wmalloc(sk, len + reserved + tlen, 0, GFP_KERNEL);
2018 /* FIXME: Save some space for broken drivers that write a hard
2019 * header at transmission time by themselves. PPP is the notable
2020 * one here. This should really be fixed at the driver level.
2022 skb_reserve(skb, reserved);
2023 skb_reset_network_header(skb);
2025 /* Try to align data part correctly */
2030 skb_reset_network_header(skb);
2032 err = memcpy_from_msg(skb_put(skb, len), msg, len);
2038 if (!dev_validate_header(dev, skb->data, len) || !skb->len) {
2042 if (len > (dev->mtu + dev->hard_header_len + extra_len) &&
2043 !packet_extra_vlan_len_allowed(dev, skb)) {
2048 sockcm_init(&sockc, sk);
2049 if (msg->msg_controllen) {
2050 err = sock_cmsg_send(sk, msg, &sockc);
2055 skb->protocol = proto;
2057 skb->priority = READ_ONCE(sk->sk_priority);
2058 skb->mark = READ_ONCE(sk->sk_mark);
2059 skb->tstamp = sockc.transmit_time;
2061 skb_setup_tx_timestamp(skb, sockc.tsflags);
2063 if (unlikely(extra_len == 4))
2066 packet_parse_headers(skb, sock);
2068 dev_queue_xmit(skb);
2079 static unsigned int run_filter(struct sk_buff *skb,
2080 const struct sock *sk,
2083 struct sk_filter *filter;
2086 filter = rcu_dereference(sk->sk_filter);
2088 res = bpf_prog_run_clear_cb(filter->prog, skb);
2094 static int packet_rcv_vnet(struct msghdr *msg, const struct sk_buff *skb,
2095 size_t *len, int vnet_hdr_sz)
2097 struct virtio_net_hdr_mrg_rxbuf vnet_hdr = { .num_buffers = 0 };
2099 if (*len < vnet_hdr_sz)
2101 *len -= vnet_hdr_sz;
2103 if (virtio_net_hdr_from_skb(skb, (struct virtio_net_hdr *)&vnet_hdr, vio_le(), true, 0))
2106 return memcpy_to_msg(msg, (void *)&vnet_hdr, vnet_hdr_sz);
2110 * This function makes lazy skb cloning in hope that most of packets
2111 * are discarded by BPF.
2113 * Note tricky part: we DO mangle shared skb! skb->data, skb->len
2114 * and skb->cb are mangled. It works because (and until) packets
2115 * falling here are owned by current CPU. Output packets are cloned
2116 * by dev_queue_xmit_nit(), input packets are processed by net_bh
2117 * sequentially, so that if we return skb to original state on exit,
2118 * we will not harm anyone.
2121 static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
2122 struct packet_type *pt, struct net_device *orig_dev)
2124 enum skb_drop_reason drop_reason = SKB_CONSUMED;
2126 struct sockaddr_ll *sll;
2127 struct packet_sock *po;
2128 u8 *skb_head = skb->data;
2129 int skb_len = skb->len;
2130 unsigned int snaplen, res;
2132 if (skb->pkt_type == PACKET_LOOPBACK)
2135 sk = pt->af_packet_priv;
2138 if (!net_eq(dev_net(dev), sock_net(sk)))
2143 if (dev_has_header(dev)) {
2144 /* The device has an explicit notion of ll header,
2145 * exported to higher levels.
2147 * Otherwise, the device hides details of its frame
2148 * structure, so that corresponding packet head is
2149 * never delivered to user.
2151 if (sk->sk_type != SOCK_DGRAM)
2152 skb_push(skb, skb->data - skb_mac_header(skb));
2153 else if (skb->pkt_type == PACKET_OUTGOING) {
2154 /* Special case: outgoing packets have ll header at head */
2155 skb_pull(skb, skb_network_offset(skb));
2161 res = run_filter(skb, sk, snaplen);
2163 goto drop_n_restore;
2167 if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf)
2170 if (skb_shared(skb)) {
2171 struct sk_buff *nskb = skb_clone(skb, GFP_ATOMIC);
2175 if (skb_head != skb->data) {
2176 skb->data = skb_head;
2183 sock_skb_cb_check_size(sizeof(*PACKET_SKB_CB(skb)) + MAX_ADDR_LEN - 8);
2185 sll = &PACKET_SKB_CB(skb)->sa.ll;
2186 sll->sll_hatype = dev->type;
2187 sll->sll_pkttype = skb->pkt_type;
2188 if (unlikely(packet_sock_flag(po, PACKET_SOCK_ORIGDEV)))
2189 sll->sll_ifindex = orig_dev->ifindex;
2191 sll->sll_ifindex = dev->ifindex;
2193 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
2195 /* sll->sll_family and sll->sll_protocol are set in packet_recvmsg().
2196 * Use their space for storing the original skb length.
2198 PACKET_SKB_CB(skb)->sa.origlen = skb->len;
2200 if (pskb_trim(skb, snaplen))
2203 skb_set_owner_r(skb, sk);
2207 /* drop conntrack reference */
2210 spin_lock(&sk->sk_receive_queue.lock);
2211 po->stats.stats1.tp_packets++;
2212 sock_skb_set_dropcount(sk, skb);
2213 skb_clear_delivery_time(skb);
2214 __skb_queue_tail(&sk->sk_receive_queue, skb);
2215 spin_unlock(&sk->sk_receive_queue.lock);
2216 sk->sk_data_ready(sk);
2220 atomic_inc(&po->tp_drops);
2221 atomic_inc(&sk->sk_drops);
2222 drop_reason = SKB_DROP_REASON_PACKET_SOCK_ERROR;
2225 if (skb_head != skb->data && skb_shared(skb)) {
2226 skb->data = skb_head;
2230 kfree_skb_reason(skb, drop_reason);
2234 static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev,
2235 struct packet_type *pt, struct net_device *orig_dev)
2237 enum skb_drop_reason drop_reason = SKB_CONSUMED;
2239 struct packet_sock *po;
2240 struct sockaddr_ll *sll;
2241 union tpacket_uhdr h;
2242 u8 *skb_head = skb->data;
2243 int skb_len = skb->len;
2244 unsigned int snaplen, res;
2245 unsigned long status = TP_STATUS_USER;
2246 unsigned short macoff, hdrlen;
2247 unsigned int netoff;
2248 struct sk_buff *copy_skb = NULL;
2249 struct timespec64 ts;
2251 unsigned int slot_id = 0;
2252 int vnet_hdr_sz = 0;
2254 /* struct tpacket{2,3}_hdr is aligned to a multiple of TPACKET_ALIGNMENT.
2255 * We may add members to them until current aligned size without forcing
2256 * userspace to call getsockopt(..., PACKET_HDRLEN, ...).
2258 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h2)) != 32);
2259 BUILD_BUG_ON(TPACKET_ALIGN(sizeof(*h.h3)) != 48);
2261 if (skb->pkt_type == PACKET_LOOPBACK)
2264 sk = pt->af_packet_priv;
2267 if (!net_eq(dev_net(dev), sock_net(sk)))
2270 if (dev_has_header(dev)) {
2271 if (sk->sk_type != SOCK_DGRAM)
2272 skb_push(skb, skb->data - skb_mac_header(skb));
2273 else if (skb->pkt_type == PACKET_OUTGOING) {
2274 /* Special case: outgoing packets have ll header at head */
2275 skb_pull(skb, skb_network_offset(skb));
2281 res = run_filter(skb, sk, snaplen);
2283 goto drop_n_restore;
2285 /* If we are flooded, just give up */
2286 if (__packet_rcv_has_room(po, skb) == ROOM_NONE) {
2287 atomic_inc(&po->tp_drops);
2288 goto drop_n_restore;
2291 if (skb->ip_summed == CHECKSUM_PARTIAL)
2292 status |= TP_STATUS_CSUMNOTREADY;
2293 else if (skb->pkt_type != PACKET_OUTGOING &&
2294 skb_csum_unnecessary(skb))
2295 status |= TP_STATUS_CSUM_VALID;
2296 if (skb_is_gso(skb) && skb_is_gso_tcp(skb))
2297 status |= TP_STATUS_GSO_TCP;
2302 if (sk->sk_type == SOCK_DGRAM) {
2303 macoff = netoff = TPACKET_ALIGN(po->tp_hdrlen) + 16 +
2306 unsigned int maclen = skb_network_offset(skb);
2307 netoff = TPACKET_ALIGN(po->tp_hdrlen +
2308 (maclen < 16 ? 16 : maclen)) +
2310 vnet_hdr_sz = READ_ONCE(po->vnet_hdr_sz);
2312 netoff += vnet_hdr_sz;
2313 macoff = netoff - maclen;
2315 if (netoff > USHRT_MAX) {
2316 atomic_inc(&po->tp_drops);
2317 goto drop_n_restore;
2319 if (po->tp_version <= TPACKET_V2) {
2320 if (macoff + snaplen > po->rx_ring.frame_size) {
2321 if (po->copy_thresh &&
2322 atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf) {
2323 if (skb_shared(skb)) {
2324 copy_skb = skb_clone(skb, GFP_ATOMIC);
2326 copy_skb = skb_get(skb);
2327 skb_head = skb->data;
2330 memset(&PACKET_SKB_CB(copy_skb)->sa.ll, 0,
2331 sizeof(PACKET_SKB_CB(copy_skb)->sa.ll));
2332 skb_set_owner_r(copy_skb, sk);
2335 snaplen = po->rx_ring.frame_size - macoff;
2336 if ((int)snaplen < 0) {
2341 } else if (unlikely(macoff + snaplen >
2342 GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len)) {
2345 nval = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len - macoff;
2346 pr_err_once("tpacket_rcv: packet too big, clamped from %u to %u. macoff=%u\n",
2347 snaplen, nval, macoff);
2349 if (unlikely((int)snaplen < 0)) {
2351 macoff = GET_PBDQC_FROM_RB(&po->rx_ring)->max_frame_len;
2355 spin_lock(&sk->sk_receive_queue.lock);
2356 h.raw = packet_current_rx_frame(po, skb,
2357 TP_STATUS_KERNEL, (macoff+snaplen));
2359 goto drop_n_account;
2361 if (po->tp_version <= TPACKET_V2) {
2362 slot_id = po->rx_ring.head;
2363 if (test_bit(slot_id, po->rx_ring.rx_owner_map))
2364 goto drop_n_account;
2365 __set_bit(slot_id, po->rx_ring.rx_owner_map);
2369 virtio_net_hdr_from_skb(skb, h.raw + macoff -
2370 sizeof(struct virtio_net_hdr),
2371 vio_le(), true, 0)) {
2372 if (po->tp_version == TPACKET_V3)
2373 prb_clear_blk_fill_status(&po->rx_ring);
2374 goto drop_n_account;
2377 if (po->tp_version <= TPACKET_V2) {
2378 packet_increment_rx_head(po, &po->rx_ring);
2380 * LOSING will be reported till you read the stats,
2381 * because it's COR - Clear On Read.
2382 * Anyways, moving it for V1/V2 only as V3 doesn't need this
2385 if (atomic_read(&po->tp_drops))
2386 status |= TP_STATUS_LOSING;
2389 po->stats.stats1.tp_packets++;
2391 status |= TP_STATUS_COPY;
2392 skb_clear_delivery_time(copy_skb);
2393 __skb_queue_tail(&sk->sk_receive_queue, copy_skb);
2395 spin_unlock(&sk->sk_receive_queue.lock);
2397 skb_copy_bits(skb, 0, h.raw + macoff, snaplen);
2399 /* Always timestamp; prefer an existing software timestamp taken
2400 * closer to the time of capture.
2402 ts_status = tpacket_get_timestamp(skb, &ts,
2403 READ_ONCE(po->tp_tstamp) |
2404 SOF_TIMESTAMPING_SOFTWARE);
2406 ktime_get_real_ts64(&ts);
2408 status |= ts_status;
2410 switch (po->tp_version) {
2412 h.h1->tp_len = skb->len;
2413 h.h1->tp_snaplen = snaplen;
2414 h.h1->tp_mac = macoff;
2415 h.h1->tp_net = netoff;
2416 h.h1->tp_sec = ts.tv_sec;
2417 h.h1->tp_usec = ts.tv_nsec / NSEC_PER_USEC;
2418 hdrlen = sizeof(*h.h1);
2421 h.h2->tp_len = skb->len;
2422 h.h2->tp_snaplen = snaplen;
2423 h.h2->tp_mac = macoff;
2424 h.h2->tp_net = netoff;
2425 h.h2->tp_sec = ts.tv_sec;
2426 h.h2->tp_nsec = ts.tv_nsec;
2427 if (skb_vlan_tag_present(skb)) {
2428 h.h2->tp_vlan_tci = skb_vlan_tag_get(skb);
2429 h.h2->tp_vlan_tpid = ntohs(skb->vlan_proto);
2430 status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
2432 h.h2->tp_vlan_tci = 0;
2433 h.h2->tp_vlan_tpid = 0;
2435 memset(h.h2->tp_padding, 0, sizeof(h.h2->tp_padding));
2436 hdrlen = sizeof(*h.h2);
2439 /* tp_nxt_offset,vlan are already populated above.
2440 * So DONT clear those fields here
2442 h.h3->tp_status |= status;
2443 h.h3->tp_len = skb->len;
2444 h.h3->tp_snaplen = snaplen;
2445 h.h3->tp_mac = macoff;
2446 h.h3->tp_net = netoff;
2447 h.h3->tp_sec = ts.tv_sec;
2448 h.h3->tp_nsec = ts.tv_nsec;
2449 memset(h.h3->tp_padding, 0, sizeof(h.h3->tp_padding));
2450 hdrlen = sizeof(*h.h3);
2456 sll = h.raw + TPACKET_ALIGN(hdrlen);
2457 sll->sll_halen = dev_parse_header(skb, sll->sll_addr);
2458 sll->sll_family = AF_PACKET;
2459 sll->sll_hatype = dev->type;
2460 sll->sll_protocol = skb->protocol;
2461 sll->sll_pkttype = skb->pkt_type;
2462 if (unlikely(packet_sock_flag(po, PACKET_SOCK_ORIGDEV)))
2463 sll->sll_ifindex = orig_dev->ifindex;
2465 sll->sll_ifindex = dev->ifindex;
2469 #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE == 1
2470 if (po->tp_version <= TPACKET_V2) {
2473 end = (u8 *) PAGE_ALIGN((unsigned long) h.raw +
2476 for (start = h.raw; start < end; start += PAGE_SIZE)
2477 flush_dcache_page(pgv_to_page(start));
2482 if (po->tp_version <= TPACKET_V2) {
2483 spin_lock(&sk->sk_receive_queue.lock);
2484 __packet_set_status(po, h.raw, status);
2485 __clear_bit(slot_id, po->rx_ring.rx_owner_map);
2486 spin_unlock(&sk->sk_receive_queue.lock);
2487 sk->sk_data_ready(sk);
2488 } else if (po->tp_version == TPACKET_V3) {
2489 prb_clear_blk_fill_status(&po->rx_ring);
2493 if (skb_head != skb->data && skb_shared(skb)) {
2494 skb->data = skb_head;
2498 kfree_skb_reason(skb, drop_reason);
2502 spin_unlock(&sk->sk_receive_queue.lock);
2503 atomic_inc(&po->tp_drops);
2504 drop_reason = SKB_DROP_REASON_PACKET_SOCK_ERROR;
2506 sk->sk_data_ready(sk);
2507 kfree_skb_reason(copy_skb, drop_reason);
2508 goto drop_n_restore;
2511 static void tpacket_destruct_skb(struct sk_buff *skb)
2513 struct packet_sock *po = pkt_sk(skb->sk);
2515 if (likely(po->tx_ring.pg_vec)) {
2519 ph = skb_zcopy_get_nouarg(skb);
2520 packet_dec_pending(&po->tx_ring);
2522 ts = __packet_set_timestamp(po, ph, skb);
2523 __packet_set_status(po, ph, TP_STATUS_AVAILABLE | ts);
2525 if (!packet_read_pending(&po->tx_ring))
2526 complete(&po->skb_completion);
2532 static int __packet_snd_vnet_parse(struct virtio_net_hdr *vnet_hdr, size_t len)
2534 if ((vnet_hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
2535 (__virtio16_to_cpu(vio_le(), vnet_hdr->csum_start) +
2536 __virtio16_to_cpu(vio_le(), vnet_hdr->csum_offset) + 2 >
2537 __virtio16_to_cpu(vio_le(), vnet_hdr->hdr_len)))
2538 vnet_hdr->hdr_len = __cpu_to_virtio16(vio_le(),
2539 __virtio16_to_cpu(vio_le(), vnet_hdr->csum_start) +
2540 __virtio16_to_cpu(vio_le(), vnet_hdr->csum_offset) + 2);
2542 if (__virtio16_to_cpu(vio_le(), vnet_hdr->hdr_len) > len)
2548 static int packet_snd_vnet_parse(struct msghdr *msg, size_t *len,
2549 struct virtio_net_hdr *vnet_hdr, int vnet_hdr_sz)
2553 if (*len < vnet_hdr_sz)
2555 *len -= vnet_hdr_sz;
2557 if (!copy_from_iter_full(vnet_hdr, sizeof(*vnet_hdr), &msg->msg_iter))
2560 ret = __packet_snd_vnet_parse(vnet_hdr, *len);
2564 /* move iter to point to the start of mac header */
2565 if (vnet_hdr_sz != sizeof(struct virtio_net_hdr))
2566 iov_iter_advance(&msg->msg_iter, vnet_hdr_sz - sizeof(struct virtio_net_hdr));
2571 static int tpacket_fill_skb(struct packet_sock *po, struct sk_buff *skb,
2572 void *frame, struct net_device *dev, void *data, int tp_len,
2573 __be16 proto, unsigned char *addr, int hlen, int copylen,
2574 const struct sockcm_cookie *sockc)
2576 union tpacket_uhdr ph;
2577 int to_write, offset, len, nr_frags, len_max;
2578 struct socket *sock = po->sk.sk_socket;
2584 skb->protocol = proto;
2586 skb->priority = READ_ONCE(po->sk.sk_priority);
2587 skb->mark = READ_ONCE(po->sk.sk_mark);
2588 skb->tstamp = sockc->transmit_time;
2589 skb_setup_tx_timestamp(skb, sockc->tsflags);
2590 skb_zcopy_set_nouarg(skb, ph.raw);
2592 skb_reserve(skb, hlen);
2593 skb_reset_network_header(skb);
2597 if (sock->type == SOCK_DGRAM) {
2598 err = dev_hard_header(skb, dev, ntohs(proto), addr,
2600 if (unlikely(err < 0))
2602 } else if (copylen) {
2603 int hdrlen = min_t(int, copylen, tp_len);
2605 skb_push(skb, dev->hard_header_len);
2606 skb_put(skb, copylen - dev->hard_header_len);
2607 err = skb_store_bits(skb, 0, data, hdrlen);
2610 if (!dev_validate_header(dev, skb->data, hdrlen))
2617 offset = offset_in_page(data);
2618 len_max = PAGE_SIZE - offset;
2619 len = ((to_write > len_max) ? len_max : to_write);
2621 skb->data_len = to_write;
2622 skb->len += to_write;
2623 skb->truesize += to_write;
2624 refcount_add(to_write, &po->sk.sk_wmem_alloc);
2626 while (likely(to_write)) {
2627 nr_frags = skb_shinfo(skb)->nr_frags;
2629 if (unlikely(nr_frags >= MAX_SKB_FRAGS)) {
2630 pr_err("Packet exceed the number of skb frags(%u)\n",
2631 (unsigned int)MAX_SKB_FRAGS);
2635 page = pgv_to_page(data);
2637 flush_dcache_page(page);
2639 skb_fill_page_desc(skb, nr_frags, page, offset, len);
2642 len_max = PAGE_SIZE;
2643 len = ((to_write > len_max) ? len_max : to_write);
2646 packet_parse_headers(skb, sock);
2651 static int tpacket_parse_header(struct packet_sock *po, void *frame,
2652 int size_max, void **data)
2654 union tpacket_uhdr ph;
2659 switch (po->tp_version) {
2661 if (ph.h3->tp_next_offset != 0) {
2662 pr_warn_once("variable sized slot not supported");
2665 tp_len = ph.h3->tp_len;
2668 tp_len = ph.h2->tp_len;
2671 tp_len = ph.h1->tp_len;
2674 if (unlikely(tp_len > size_max)) {
2675 pr_err("packet size is too long (%d > %d)\n", tp_len, size_max);
2679 if (unlikely(packet_sock_flag(po, PACKET_SOCK_TX_HAS_OFF))) {
2680 int off_min, off_max;
2682 off_min = po->tp_hdrlen - sizeof(struct sockaddr_ll);
2683 off_max = po->tx_ring.frame_size - tp_len;
2684 if (po->sk.sk_type == SOCK_DGRAM) {
2685 switch (po->tp_version) {
2687 off = ph.h3->tp_net;
2690 off = ph.h2->tp_net;
2693 off = ph.h1->tp_net;
2697 switch (po->tp_version) {
2699 off = ph.h3->tp_mac;
2702 off = ph.h2->tp_mac;
2705 off = ph.h1->tp_mac;
2709 if (unlikely((off < off_min) || (off_max < off)))
2712 off = po->tp_hdrlen - sizeof(struct sockaddr_ll);
2715 *data = frame + off;
2719 static int tpacket_snd(struct packet_sock *po, struct msghdr *msg)
2721 struct sk_buff *skb = NULL;
2722 struct net_device *dev;
2723 struct virtio_net_hdr *vnet_hdr = NULL;
2724 struct sockcm_cookie sockc;
2726 int err, reserve = 0;
2728 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2729 bool need_wait = !(msg->msg_flags & MSG_DONTWAIT);
2730 int vnet_hdr_sz = READ_ONCE(po->vnet_hdr_sz);
2731 unsigned char *addr = NULL;
2732 int tp_len, size_max;
2735 int status = TP_STATUS_AVAILABLE;
2736 int hlen, tlen, copylen = 0;
2739 mutex_lock(&po->pg_vec_lock);
2741 /* packet_sendmsg() check on tx_ring.pg_vec was lockless,
2742 * we need to confirm it under protection of pg_vec_lock.
2744 if (unlikely(!po->tx_ring.pg_vec)) {
2748 if (likely(saddr == NULL)) {
2749 dev = packet_cached_dev_get(po);
2750 proto = READ_ONCE(po->num);
2753 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2755 if (msg->msg_namelen < (saddr->sll_halen
2756 + offsetof(struct sockaddr_ll,
2759 proto = saddr->sll_protocol;
2760 dev = dev_get_by_index(sock_net(&po->sk), saddr->sll_ifindex);
2761 if (po->sk.sk_socket->type == SOCK_DGRAM) {
2762 if (dev && msg->msg_namelen < dev->addr_len +
2763 offsetof(struct sockaddr_ll, sll_addr))
2765 addr = saddr->sll_addr;
2770 if (unlikely(dev == NULL))
2773 if (unlikely(!(dev->flags & IFF_UP)))
2776 sockcm_init(&sockc, &po->sk);
2777 if (msg->msg_controllen) {
2778 err = sock_cmsg_send(&po->sk, msg, &sockc);
2783 if (po->sk.sk_socket->type == SOCK_RAW)
2784 reserve = dev->hard_header_len;
2785 size_max = po->tx_ring.frame_size
2786 - (po->tp_hdrlen - sizeof(struct sockaddr_ll));
2788 if ((size_max > dev->mtu + reserve + VLAN_HLEN) && !vnet_hdr_sz)
2789 size_max = dev->mtu + reserve + VLAN_HLEN;
2791 reinit_completion(&po->skb_completion);
2794 ph = packet_current_frame(po, &po->tx_ring,
2795 TP_STATUS_SEND_REQUEST);
2796 if (unlikely(ph == NULL)) {
2797 if (need_wait && skb) {
2798 timeo = sock_sndtimeo(&po->sk, msg->msg_flags & MSG_DONTWAIT);
2799 timeo = wait_for_completion_interruptible_timeout(&po->skb_completion, timeo);
2801 err = !timeo ? -ETIMEDOUT : -ERESTARTSYS;
2805 /* check for additional frames */
2810 tp_len = tpacket_parse_header(po, ph, size_max, &data);
2814 status = TP_STATUS_SEND_REQUEST;
2815 hlen = LL_RESERVED_SPACE(dev);
2816 tlen = dev->needed_tailroom;
2819 data += vnet_hdr_sz;
2820 tp_len -= vnet_hdr_sz;
2822 __packet_snd_vnet_parse(vnet_hdr, tp_len)) {
2826 copylen = __virtio16_to_cpu(vio_le(),
2829 copylen = max_t(int, copylen, dev->hard_header_len);
2830 skb = sock_alloc_send_skb(&po->sk,
2831 hlen + tlen + sizeof(struct sockaddr_ll) +
2832 (copylen - dev->hard_header_len),
2835 if (unlikely(skb == NULL)) {
2836 /* we assume the socket was initially writeable ... */
2837 if (likely(len_sum > 0))
2841 tp_len = tpacket_fill_skb(po, skb, ph, dev, data, tp_len, proto,
2842 addr, hlen, copylen, &sockc);
2843 if (likely(tp_len >= 0) &&
2844 tp_len > dev->mtu + reserve &&
2846 !packet_extra_vlan_len_allowed(dev, skb))
2849 if (unlikely(tp_len < 0)) {
2851 if (packet_sock_flag(po, PACKET_SOCK_TP_LOSS)) {
2852 __packet_set_status(po, ph,
2853 TP_STATUS_AVAILABLE);
2854 packet_increment_head(&po->tx_ring);
2858 status = TP_STATUS_WRONG_FORMAT;
2865 if (virtio_net_hdr_to_skb(skb, vnet_hdr, vio_le())) {
2869 virtio_net_hdr_set_proto(skb, vnet_hdr);
2872 skb->destructor = tpacket_destruct_skb;
2873 __packet_set_status(po, ph, TP_STATUS_SENDING);
2874 packet_inc_pending(&po->tx_ring);
2876 status = TP_STATUS_SEND_REQUEST;
2877 err = packet_xmit(po, skb);
2878 if (unlikely(err != 0)) {
2880 err = net_xmit_errno(err);
2881 if (err && __packet_get_status(po, ph) ==
2882 TP_STATUS_AVAILABLE) {
2883 /* skb was destructed already */
2888 * skb was dropped but not destructed yet;
2889 * let's treat it like congestion or err < 0
2893 packet_increment_head(&po->tx_ring);
2895 } while (likely((ph != NULL) ||
2896 /* Note: packet_read_pending() might be slow if we have
2897 * to call it as it's per_cpu variable, but in fast-path
2898 * we already short-circuit the loop with the first
2899 * condition, and luckily don't have to go that path
2902 (need_wait && packet_read_pending(&po->tx_ring))));
2908 __packet_set_status(po, ph, status);
2913 mutex_unlock(&po->pg_vec_lock);
2917 static struct sk_buff *packet_alloc_skb(struct sock *sk, size_t prepad,
2918 size_t reserve, size_t len,
2919 size_t linear, int noblock,
2922 struct sk_buff *skb;
2924 /* Under a page? Don't bother with paged skb. */
2925 if (prepad + len < PAGE_SIZE || !linear)
2928 if (len - linear > MAX_SKB_FRAGS * (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER))
2929 linear = len - MAX_SKB_FRAGS * (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER);
2930 skb = sock_alloc_send_pskb(sk, prepad + linear, len - linear, noblock,
2931 err, PAGE_ALLOC_COSTLY_ORDER);
2935 skb_reserve(skb, reserve);
2936 skb_put(skb, linear);
2937 skb->data_len = len - linear;
2938 skb->len += len - linear;
2943 static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
2945 struct sock *sk = sock->sk;
2946 DECLARE_SOCKADDR(struct sockaddr_ll *, saddr, msg->msg_name);
2947 struct sk_buff *skb;
2948 struct net_device *dev;
2950 unsigned char *addr = NULL;
2951 int err, reserve = 0;
2952 struct sockcm_cookie sockc;
2953 struct virtio_net_hdr vnet_hdr = { 0 };
2955 struct packet_sock *po = pkt_sk(sk);
2956 int vnet_hdr_sz = READ_ONCE(po->vnet_hdr_sz);
2957 int hlen, tlen, linear;
2961 * Get and verify the address.
2964 if (likely(saddr == NULL)) {
2965 dev = packet_cached_dev_get(po);
2966 proto = READ_ONCE(po->num);
2969 if (msg->msg_namelen < sizeof(struct sockaddr_ll))
2971 if (msg->msg_namelen < (saddr->sll_halen + offsetof(struct sockaddr_ll, sll_addr)))
2973 proto = saddr->sll_protocol;
2974 dev = dev_get_by_index(sock_net(sk), saddr->sll_ifindex);
2975 if (sock->type == SOCK_DGRAM) {
2976 if (dev && msg->msg_namelen < dev->addr_len +
2977 offsetof(struct sockaddr_ll, sll_addr))
2979 addr = saddr->sll_addr;
2984 if (unlikely(dev == NULL))
2987 if (unlikely(!(dev->flags & IFF_UP)))
2990 sockcm_init(&sockc, sk);
2991 sockc.mark = READ_ONCE(sk->sk_mark);
2992 if (msg->msg_controllen) {
2993 err = sock_cmsg_send(sk, msg, &sockc);
2998 if (sock->type == SOCK_RAW)
2999 reserve = dev->hard_header_len;
3001 err = packet_snd_vnet_parse(msg, &len, &vnet_hdr, vnet_hdr_sz);
3006 if (unlikely(sock_flag(sk, SOCK_NOFCS))) {
3007 if (!netif_supports_nofcs(dev)) {
3008 err = -EPROTONOSUPPORT;
3011 extra_len = 4; /* We're doing our own CRC */
3015 if (!vnet_hdr.gso_type &&
3016 (len > dev->mtu + reserve + VLAN_HLEN + extra_len))
3020 hlen = LL_RESERVED_SPACE(dev);
3021 tlen = dev->needed_tailroom;
3022 linear = __virtio16_to_cpu(vio_le(), vnet_hdr.hdr_len);
3023 linear = max(linear, min_t(int, len, dev->hard_header_len));
3024 skb = packet_alloc_skb(sk, hlen + tlen, hlen, len, linear,
3025 msg->msg_flags & MSG_DONTWAIT, &err);
3029 skb_reset_network_header(skb);
3032 if (sock->type == SOCK_DGRAM) {
3033 offset = dev_hard_header(skb, dev, ntohs(proto), addr, NULL, len);
3034 if (unlikely(offset < 0))
3036 } else if (reserve) {
3037 skb_reserve(skb, -reserve);
3038 if (len < reserve + sizeof(struct ipv6hdr) &&
3039 dev->min_header_len != dev->hard_header_len)
3040 skb_reset_network_header(skb);
3043 /* Returns -EFAULT on error */
3044 err = skb_copy_datagram_from_iter(skb, offset, &msg->msg_iter, len);
3048 if ((sock->type == SOCK_RAW &&
3049 !dev_validate_header(dev, skb->data, len)) || !skb->len) {
3054 skb_setup_tx_timestamp(skb, sockc.tsflags);
3056 if (!vnet_hdr.gso_type && (len > dev->mtu + reserve + extra_len) &&
3057 !packet_extra_vlan_len_allowed(dev, skb)) {
3062 skb->protocol = proto;
3064 skb->priority = READ_ONCE(sk->sk_priority);
3065 skb->mark = sockc.mark;
3066 skb->tstamp = sockc.transmit_time;
3068 if (unlikely(extra_len == 4))
3071 packet_parse_headers(skb, sock);
3074 err = virtio_net_hdr_to_skb(skb, &vnet_hdr, vio_le());
3078 virtio_net_hdr_set_proto(skb, &vnet_hdr);
3081 err = packet_xmit(po, skb);
3083 if (unlikely(err != 0)) {
3085 err = net_xmit_errno(err);
3102 static int packet_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
3104 struct sock *sk = sock->sk;
3105 struct packet_sock *po = pkt_sk(sk);
3107 /* Reading tx_ring.pg_vec without holding pg_vec_lock is racy.
3108 * tpacket_snd() will redo the check safely.
3110 if (data_race(po->tx_ring.pg_vec))
3111 return tpacket_snd(po, msg);
3113 return packet_snd(sock, msg, len);
3117 * Close a PACKET socket. This is fairly simple. We immediately go
3118 * to 'closed' state and remove our protocol entry in the device list.
3121 static int packet_release(struct socket *sock)
3123 struct sock *sk = sock->sk;
3124 struct packet_sock *po;
3125 struct packet_fanout *f;
3127 union tpacket_req_u req_u;
3135 mutex_lock(&net->packet.sklist_lock);
3136 sk_del_node_init_rcu(sk);
3137 mutex_unlock(&net->packet.sklist_lock);
3139 sock_prot_inuse_add(net, sk->sk_prot, -1);
3141 spin_lock(&po->bind_lock);
3142 unregister_prot_hook(sk, false);
3143 packet_cached_dev_reset(po);
3145 if (po->prot_hook.dev) {
3146 netdev_put(po->prot_hook.dev, &po->prot_hook.dev_tracker);
3147 po->prot_hook.dev = NULL;
3149 spin_unlock(&po->bind_lock);
3151 packet_flush_mclist(sk);
3154 if (po->rx_ring.pg_vec) {
3155 memset(&req_u, 0, sizeof(req_u));
3156 packet_set_ring(sk, &req_u, 1, 0);
3159 if (po->tx_ring.pg_vec) {
3160 memset(&req_u, 0, sizeof(req_u));
3161 packet_set_ring(sk, &req_u, 1, 1);
3165 f = fanout_release(sk);
3169 kfree(po->rollover);
3171 fanout_release_data(f);
3175 * Now the socket is dead. No more input will appear.
3182 skb_queue_purge(&sk->sk_receive_queue);
3183 packet_free_pending(po);
3190 * Attach a packet hook.
3193 static int packet_do_bind(struct sock *sk, const char *name, int ifindex,
3196 struct packet_sock *po = pkt_sk(sk);
3197 struct net_device *dev = NULL;
3198 bool unlisted = false;
3203 spin_lock(&po->bind_lock);
3215 dev = dev_get_by_name_rcu(sock_net(sk), name);
3220 } else if (ifindex) {
3221 dev = dev_get_by_index_rcu(sock_net(sk), ifindex);
3228 need_rehook = po->prot_hook.type != proto || po->prot_hook.dev != dev;
3232 if (packet_sock_flag(po, PACKET_SOCK_RUNNING)) {
3234 /* prevents packet_notifier() from calling
3235 * register_prot_hook()
3237 WRITE_ONCE(po->num, 0);
3238 __unregister_prot_hook(sk, true);
3241 unlisted = !dev_get_by_index_rcu(sock_net(sk),
3245 BUG_ON(packet_sock_flag(po, PACKET_SOCK_RUNNING));
3246 WRITE_ONCE(po->num, proto);
3247 po->prot_hook.type = proto;
3249 netdev_put(po->prot_hook.dev, &po->prot_hook.dev_tracker);
3251 if (unlikely(unlisted)) {
3252 po->prot_hook.dev = NULL;
3253 WRITE_ONCE(po->ifindex, -1);
3254 packet_cached_dev_reset(po);
3256 netdev_hold(dev, &po->prot_hook.dev_tracker,
3258 po->prot_hook.dev = dev;
3259 WRITE_ONCE(po->ifindex, dev ? dev->ifindex : 0);
3260 packet_cached_dev_assign(po, dev);
3265 if (proto == 0 || !need_rehook)
3268 if (!unlisted && (!dev || (dev->flags & IFF_UP))) {
3269 register_prot_hook(sk);
3271 sk->sk_err = ENETDOWN;
3272 if (!sock_flag(sk, SOCK_DEAD))
3273 sk_error_report(sk);
3278 spin_unlock(&po->bind_lock);
3284 * Bind a packet socket to a device
3287 static int packet_bind_spkt(struct socket *sock, struct sockaddr *uaddr,
3290 struct sock *sk = sock->sk;
3291 char name[sizeof(uaddr->sa_data_min) + 1];
3297 if (addr_len != sizeof(struct sockaddr))
3299 /* uaddr->sa_data comes from the userspace, it's not guaranteed to be
3302 memcpy(name, uaddr->sa_data, sizeof(uaddr->sa_data_min));
3303 name[sizeof(uaddr->sa_data_min)] = 0;
3305 return packet_do_bind(sk, name, 0, 0);
3308 static int packet_bind(struct socket *sock, struct sockaddr *uaddr, int addr_len)
3310 struct sockaddr_ll *sll = (struct sockaddr_ll *)uaddr;
3311 struct sock *sk = sock->sk;
3317 if (addr_len < sizeof(struct sockaddr_ll))
3319 if (sll->sll_family != AF_PACKET)
3322 return packet_do_bind(sk, NULL, sll->sll_ifindex, sll->sll_protocol);
3325 static struct proto packet_proto = {
3327 .owner = THIS_MODULE,
3328 .obj_size = sizeof(struct packet_sock),
3332 * Create a packet of type SOCK_PACKET.
3335 static int packet_create(struct net *net, struct socket *sock, int protocol,
3339 struct packet_sock *po;
3340 __be16 proto = (__force __be16)protocol; /* weird, but documented */
3343 if (!ns_capable(net->user_ns, CAP_NET_RAW))
3345 if (sock->type != SOCK_DGRAM && sock->type != SOCK_RAW &&
3346 sock->type != SOCK_PACKET)
3347 return -ESOCKTNOSUPPORT;
3349 sock->state = SS_UNCONNECTED;
3352 sk = sk_alloc(net, PF_PACKET, GFP_KERNEL, &packet_proto, kern);
3356 sock->ops = &packet_ops;
3357 if (sock->type == SOCK_PACKET)
3358 sock->ops = &packet_ops_spkt;
3360 sock_init_data(sock, sk);
3363 init_completion(&po->skb_completion);
3364 sk->sk_family = PF_PACKET;
3367 err = packet_alloc_pending(po);
3371 packet_cached_dev_reset(po);
3373 sk->sk_destruct = packet_sock_destruct;
3376 * Attach a protocol block
3379 spin_lock_init(&po->bind_lock);
3380 mutex_init(&po->pg_vec_lock);
3381 po->rollover = NULL;
3382 po->prot_hook.func = packet_rcv;
3384 if (sock->type == SOCK_PACKET)
3385 po->prot_hook.func = packet_rcv_spkt;
3387 po->prot_hook.af_packet_priv = sk;
3388 po->prot_hook.af_packet_net = sock_net(sk);
3391 po->prot_hook.type = proto;
3392 __register_prot_hook(sk);
3395 mutex_lock(&net->packet.sklist_lock);
3396 sk_add_node_tail_rcu(sk, &net->packet.sklist);
3397 mutex_unlock(&net->packet.sklist_lock);
3399 sock_prot_inuse_add(net, &packet_proto, 1);
3409 * Pull a packet from our receive queue and hand it to the user.
3410 * If necessary we block.
3413 static int packet_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
3416 struct sock *sk = sock->sk;
3417 struct sk_buff *skb;
3419 int vnet_hdr_len = READ_ONCE(pkt_sk(sk)->vnet_hdr_sz);
3420 unsigned int origlen = 0;
3423 if (flags & ~(MSG_PEEK|MSG_DONTWAIT|MSG_TRUNC|MSG_CMSG_COMPAT|MSG_ERRQUEUE))
3427 /* What error should we return now? EUNATTACH? */
3428 if (pkt_sk(sk)->ifindex < 0)
3432 if (flags & MSG_ERRQUEUE) {
3433 err = sock_recv_errqueue(sk, msg, len,
3434 SOL_PACKET, PACKET_TX_TIMESTAMP);
3439 * Call the generic datagram receiver. This handles all sorts
3440 * of horrible races and re-entrancy so we can forget about it
3441 * in the protocol layers.
3443 * Now it will return ENETDOWN, if device have just gone down,
3444 * but then it will block.
3447 skb = skb_recv_datagram(sk, flags, &err);
3450 * An error occurred so return it. Because skb_recv_datagram()
3451 * handles the blocking we don't see and worry about blocking
3458 packet_rcv_try_clear_pressure(pkt_sk(sk));
3461 err = packet_rcv_vnet(msg, skb, &len, vnet_hdr_len);
3466 /* You lose any data beyond the buffer you gave. If it worries
3467 * a user program they can ask the device for its MTU
3473 msg->msg_flags |= MSG_TRUNC;
3476 err = skb_copy_datagram_msg(skb, 0, msg, copied);
3480 if (sock->type != SOCK_PACKET) {
3481 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
3483 /* Original length was stored in sockaddr_ll fields */
3484 origlen = PACKET_SKB_CB(skb)->sa.origlen;
3485 sll->sll_family = AF_PACKET;
3486 sll->sll_protocol = skb->protocol;
3489 sock_recv_cmsgs(msg, sk, skb);
3491 if (msg->msg_name) {
3492 const size_t max_len = min(sizeof(skb->cb),
3493 sizeof(struct sockaddr_storage));
3496 /* If the address length field is there to be filled
3497 * in, we fill it in now.
3499 if (sock->type == SOCK_PACKET) {
3500 __sockaddr_check_size(sizeof(struct sockaddr_pkt));
3501 msg->msg_namelen = sizeof(struct sockaddr_pkt);
3502 copy_len = msg->msg_namelen;
3504 struct sockaddr_ll *sll = &PACKET_SKB_CB(skb)->sa.ll;
3506 msg->msg_namelen = sll->sll_halen +
3507 offsetof(struct sockaddr_ll, sll_addr);
3508 copy_len = msg->msg_namelen;
3509 if (msg->msg_namelen < sizeof(struct sockaddr_ll)) {
3510 memset(msg->msg_name +
3511 offsetof(struct sockaddr_ll, sll_addr),
3512 0, sizeof(sll->sll_addr));
3513 msg->msg_namelen = sizeof(struct sockaddr_ll);
3516 if (WARN_ON_ONCE(copy_len > max_len)) {
3518 msg->msg_namelen = copy_len;
3520 memcpy(msg->msg_name, &PACKET_SKB_CB(skb)->sa, copy_len);
3523 if (packet_sock_flag(pkt_sk(sk), PACKET_SOCK_AUXDATA)) {
3524 struct tpacket_auxdata aux;
3526 aux.tp_status = TP_STATUS_USER;
3527 if (skb->ip_summed == CHECKSUM_PARTIAL)
3528 aux.tp_status |= TP_STATUS_CSUMNOTREADY;
3529 else if (skb->pkt_type != PACKET_OUTGOING &&
3530 skb_csum_unnecessary(skb))
3531 aux.tp_status |= TP_STATUS_CSUM_VALID;
3532 if (skb_is_gso(skb) && skb_is_gso_tcp(skb))
3533 aux.tp_status |= TP_STATUS_GSO_TCP;
3535 aux.tp_len = origlen;
3536 aux.tp_snaplen = skb->len;
3538 aux.tp_net = skb_network_offset(skb);
3539 if (skb_vlan_tag_present(skb)) {
3540 aux.tp_vlan_tci = skb_vlan_tag_get(skb);
3541 aux.tp_vlan_tpid = ntohs(skb->vlan_proto);
3542 aux.tp_status |= TP_STATUS_VLAN_VALID | TP_STATUS_VLAN_TPID_VALID;
3544 aux.tp_vlan_tci = 0;
3545 aux.tp_vlan_tpid = 0;
3547 put_cmsg(msg, SOL_PACKET, PACKET_AUXDATA, sizeof(aux), &aux);
3551 * Free or return the buffer as appropriate. Again this
3552 * hides all the races and re-entrancy issues from us.
3554 err = vnet_hdr_len + ((flags&MSG_TRUNC) ? skb->len : copied);
3557 skb_free_datagram(sk, skb);
3562 static int packet_getname_spkt(struct socket *sock, struct sockaddr *uaddr,
3565 struct net_device *dev;
3566 struct sock *sk = sock->sk;
3571 uaddr->sa_family = AF_PACKET;
3572 memset(uaddr->sa_data, 0, sizeof(uaddr->sa_data_min));
3574 dev = dev_get_by_index_rcu(sock_net(sk), READ_ONCE(pkt_sk(sk)->ifindex));
3576 strscpy(uaddr->sa_data, dev->name, sizeof(uaddr->sa_data_min));
3579 return sizeof(*uaddr);
3582 static int packet_getname(struct socket *sock, struct sockaddr *uaddr,
3585 struct net_device *dev;
3586 struct sock *sk = sock->sk;
3587 struct packet_sock *po = pkt_sk(sk);
3588 DECLARE_SOCKADDR(struct sockaddr_ll *, sll, uaddr);
3594 ifindex = READ_ONCE(po->ifindex);
3595 sll->sll_family = AF_PACKET;
3596 sll->sll_ifindex = ifindex;
3597 sll->sll_protocol = READ_ONCE(po->num);
3598 sll->sll_pkttype = 0;
3600 dev = dev_get_by_index_rcu(sock_net(sk), ifindex);
3602 sll->sll_hatype = dev->type;
3603 sll->sll_halen = dev->addr_len;
3605 /* Let __fortify_memcpy_chk() know the actual buffer size. */
3606 memcpy(((struct sockaddr_storage *)sll)->__data +
3607 offsetof(struct sockaddr_ll, sll_addr) -
3608 offsetofend(struct sockaddr_ll, sll_family),
3609 dev->dev_addr, dev->addr_len);
3611 sll->sll_hatype = 0; /* Bad: we have no ARPHRD_UNSPEC */
3616 return offsetof(struct sockaddr_ll, sll_addr) + sll->sll_halen;
3619 static int packet_dev_mc(struct net_device *dev, struct packet_mclist *i,
3623 case PACKET_MR_MULTICAST:
3624 if (i->alen != dev->addr_len)
3627 return dev_mc_add(dev, i->addr);
3629 return dev_mc_del(dev, i->addr);
3631 case PACKET_MR_PROMISC:
3632 return dev_set_promiscuity(dev, what);
3633 case PACKET_MR_ALLMULTI:
3634 return dev_set_allmulti(dev, what);
3635 case PACKET_MR_UNICAST:
3636 if (i->alen != dev->addr_len)
3639 return dev_uc_add(dev, i->addr);
3641 return dev_uc_del(dev, i->addr);
3649 static void packet_dev_mclist_delete(struct net_device *dev,
3650 struct packet_mclist **mlp)
3652 struct packet_mclist *ml;
3654 while ((ml = *mlp) != NULL) {
3655 if (ml->ifindex == dev->ifindex) {
3656 packet_dev_mc(dev, ml, -1);
3664 static int packet_mc_add(struct sock *sk, struct packet_mreq_max *mreq)
3666 struct packet_sock *po = pkt_sk(sk);
3667 struct packet_mclist *ml, *i;
3668 struct net_device *dev;
3674 dev = __dev_get_by_index(sock_net(sk), mreq->mr_ifindex);
3679 if (mreq->mr_alen > dev->addr_len)
3683 i = kmalloc(sizeof(*i), GFP_KERNEL);
3688 for (ml = po->mclist; ml; ml = ml->next) {
3689 if (ml->ifindex == mreq->mr_ifindex &&
3690 ml->type == mreq->mr_type &&
3691 ml->alen == mreq->mr_alen &&
3692 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3694 /* Free the new element ... */
3700 i->type = mreq->mr_type;
3701 i->ifindex = mreq->mr_ifindex;
3702 i->alen = mreq->mr_alen;
3703 memcpy(i->addr, mreq->mr_address, i->alen);
3704 memset(i->addr + i->alen, 0, sizeof(i->addr) - i->alen);
3706 i->next = po->mclist;
3708 err = packet_dev_mc(dev, i, 1);
3710 po->mclist = i->next;
3719 static int packet_mc_drop(struct sock *sk, struct packet_mreq_max *mreq)
3721 struct packet_mclist *ml, **mlp;
3725 for (mlp = &pkt_sk(sk)->mclist; (ml = *mlp) != NULL; mlp = &ml->next) {
3726 if (ml->ifindex == mreq->mr_ifindex &&
3727 ml->type == mreq->mr_type &&
3728 ml->alen == mreq->mr_alen &&
3729 memcmp(ml->addr, mreq->mr_address, ml->alen) == 0) {
3730 if (--ml->count == 0) {
3731 struct net_device *dev;
3733 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3735 packet_dev_mc(dev, ml, -1);
3745 static void packet_flush_mclist(struct sock *sk)
3747 struct packet_sock *po = pkt_sk(sk);
3748 struct packet_mclist *ml;
3754 while ((ml = po->mclist) != NULL) {
3755 struct net_device *dev;
3757 po->mclist = ml->next;
3758 dev = __dev_get_by_index(sock_net(sk), ml->ifindex);
3760 packet_dev_mc(dev, ml, -1);
3767 packet_setsockopt(struct socket *sock, int level, int optname, sockptr_t optval,
3768 unsigned int optlen)
3770 struct sock *sk = sock->sk;
3771 struct packet_sock *po = pkt_sk(sk);
3774 if (level != SOL_PACKET)
3775 return -ENOPROTOOPT;
3778 case PACKET_ADD_MEMBERSHIP:
3779 case PACKET_DROP_MEMBERSHIP:
3781 struct packet_mreq_max mreq;
3783 memset(&mreq, 0, sizeof(mreq));
3784 if (len < sizeof(struct packet_mreq))
3786 if (len > sizeof(mreq))
3788 if (copy_from_sockptr(&mreq, optval, len))
3790 if (len < (mreq.mr_alen + offsetof(struct packet_mreq, mr_address)))
3792 if (optname == PACKET_ADD_MEMBERSHIP)
3793 ret = packet_mc_add(sk, &mreq);
3795 ret = packet_mc_drop(sk, &mreq);
3799 case PACKET_RX_RING:
3800 case PACKET_TX_RING:
3802 union tpacket_req_u req_u;
3806 switch (po->tp_version) {
3809 len = sizeof(req_u.req);
3813 len = sizeof(req_u.req3);
3819 if (copy_from_sockptr(&req_u.req, optval, len))
3822 ret = packet_set_ring(sk, &req_u, 0,
3823 optname == PACKET_TX_RING);
3828 case PACKET_COPY_THRESH:
3832 if (optlen != sizeof(val))
3834 if (copy_from_sockptr(&val, optval, sizeof(val)))
3837 pkt_sk(sk)->copy_thresh = val;
3840 case PACKET_VERSION:
3844 if (optlen != sizeof(val))
3846 if (copy_from_sockptr(&val, optval, sizeof(val)))
3857 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
3860 po->tp_version = val;
3866 case PACKET_RESERVE:
3870 if (optlen != sizeof(val))
3872 if (copy_from_sockptr(&val, optval, sizeof(val)))
3877 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
3880 po->tp_reserve = val;
3890 if (optlen != sizeof(val))
3892 if (copy_from_sockptr(&val, optval, sizeof(val)))
3896 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
3899 packet_sock_flag_set(po, PACKET_SOCK_TP_LOSS, val);
3905 case PACKET_AUXDATA:
3909 if (optlen < sizeof(val))
3911 if (copy_from_sockptr(&val, optval, sizeof(val)))
3914 packet_sock_flag_set(po, PACKET_SOCK_AUXDATA, val);
3917 case PACKET_ORIGDEV:
3921 if (optlen < sizeof(val))
3923 if (copy_from_sockptr(&val, optval, sizeof(val)))
3926 packet_sock_flag_set(po, PACKET_SOCK_ORIGDEV, val);
3929 case PACKET_VNET_HDR:
3930 case PACKET_VNET_HDR_SZ:
3934 if (sock->type != SOCK_RAW)
3936 if (optlen < sizeof(val))
3938 if (copy_from_sockptr(&val, optval, sizeof(val)))
3941 if (optname == PACKET_VNET_HDR_SZ) {
3942 if (val && val != sizeof(struct virtio_net_hdr) &&
3943 val != sizeof(struct virtio_net_hdr_mrg_rxbuf))
3947 hdr_len = val ? sizeof(struct virtio_net_hdr) : 0;
3950 if (po->rx_ring.pg_vec || po->tx_ring.pg_vec) {
3953 WRITE_ONCE(po->vnet_hdr_sz, hdr_len);
3959 case PACKET_TIMESTAMP:
3963 if (optlen != sizeof(val))
3965 if (copy_from_sockptr(&val, optval, sizeof(val)))
3968 WRITE_ONCE(po->tp_tstamp, val);
3973 struct fanout_args args = { 0 };
3975 if (optlen != sizeof(int) && optlen != sizeof(args))
3977 if (copy_from_sockptr(&args, optval, optlen))
3980 return fanout_add(sk, &args);
3982 case PACKET_FANOUT_DATA:
3984 /* Paired with the WRITE_ONCE() in fanout_add() */
3985 if (!READ_ONCE(po->fanout))
3988 return fanout_set_data(po, optval, optlen);
3990 case PACKET_IGNORE_OUTGOING:
3994 if (optlen != sizeof(val))
3996 if (copy_from_sockptr(&val, optval, sizeof(val)))
3998 if (val < 0 || val > 1)
4001 WRITE_ONCE(po->prot_hook.ignore_outgoing, !!val);
4004 case PACKET_TX_HAS_OFF:
4008 if (optlen != sizeof(val))
4010 if (copy_from_sockptr(&val, optval, sizeof(val)))
4014 if (!po->rx_ring.pg_vec && !po->tx_ring.pg_vec)
4015 packet_sock_flag_set(po, PACKET_SOCK_TX_HAS_OFF, val);
4020 case PACKET_QDISC_BYPASS:
4024 if (optlen != sizeof(val))
4026 if (copy_from_sockptr(&val, optval, sizeof(val)))
4029 packet_sock_flag_set(po, PACKET_SOCK_QDISC_BYPASS, val);
4033 return -ENOPROTOOPT;
4037 static int packet_getsockopt(struct socket *sock, int level, int optname,
4038 char __user *optval, int __user *optlen)
4041 int val, lv = sizeof(val);
4042 struct sock *sk = sock->sk;
4043 struct packet_sock *po = pkt_sk(sk);
4045 union tpacket_stats_u st;
4046 struct tpacket_rollover_stats rstats;
4049 if (level != SOL_PACKET)
4050 return -ENOPROTOOPT;
4052 if (get_user(len, optlen))
4059 case PACKET_STATISTICS:
4060 spin_lock_bh(&sk->sk_receive_queue.lock);
4061 memcpy(&st, &po->stats, sizeof(st));
4062 memset(&po->stats, 0, sizeof(po->stats));
4063 spin_unlock_bh(&sk->sk_receive_queue.lock);
4064 drops = atomic_xchg(&po->tp_drops, 0);
4066 if (po->tp_version == TPACKET_V3) {
4067 lv = sizeof(struct tpacket_stats_v3);
4068 st.stats3.tp_drops = drops;
4069 st.stats3.tp_packets += drops;
4072 lv = sizeof(struct tpacket_stats);
4073 st.stats1.tp_drops = drops;
4074 st.stats1.tp_packets += drops;
4079 case PACKET_AUXDATA:
4080 val = packet_sock_flag(po, PACKET_SOCK_AUXDATA);
4082 case PACKET_ORIGDEV:
4083 val = packet_sock_flag(po, PACKET_SOCK_ORIGDEV);
4085 case PACKET_VNET_HDR:
4086 val = !!READ_ONCE(po->vnet_hdr_sz);
4088 case PACKET_VNET_HDR_SZ:
4089 val = READ_ONCE(po->vnet_hdr_sz);
4091 case PACKET_VERSION:
4092 val = po->tp_version;
4095 if (len > sizeof(int))
4097 if (len < sizeof(int))
4099 if (copy_from_user(&val, optval, len))
4103 val = sizeof(struct tpacket_hdr);
4106 val = sizeof(struct tpacket2_hdr);
4109 val = sizeof(struct tpacket3_hdr);
4115 case PACKET_RESERVE:
4116 val = po->tp_reserve;
4119 val = packet_sock_flag(po, PACKET_SOCK_TP_LOSS);
4121 case PACKET_TIMESTAMP:
4122 val = READ_ONCE(po->tp_tstamp);
4126 ((u32)po->fanout->id |
4127 ((u32)po->fanout->type << 16) |
4128 ((u32)po->fanout->flags << 24)) :
4131 case PACKET_IGNORE_OUTGOING:
4132 val = READ_ONCE(po->prot_hook.ignore_outgoing);
4134 case PACKET_ROLLOVER_STATS:
4137 rstats.tp_all = atomic_long_read(&po->rollover->num);
4138 rstats.tp_huge = atomic_long_read(&po->rollover->num_huge);
4139 rstats.tp_failed = atomic_long_read(&po->rollover->num_failed);
4141 lv = sizeof(rstats);
4143 case PACKET_TX_HAS_OFF:
4144 val = packet_sock_flag(po, PACKET_SOCK_TX_HAS_OFF);
4146 case PACKET_QDISC_BYPASS:
4147 val = packet_sock_flag(po, PACKET_SOCK_QDISC_BYPASS);
4150 return -ENOPROTOOPT;
4155 if (put_user(len, optlen))
4157 if (copy_to_user(optval, data, len))
4162 static int packet_notifier(struct notifier_block *this,
4163 unsigned long msg, void *ptr)
4166 struct net_device *dev = netdev_notifier_info_to_dev(ptr);
4167 struct net *net = dev_net(dev);
4170 sk_for_each_rcu(sk, &net->packet.sklist) {
4171 struct packet_sock *po = pkt_sk(sk);
4174 case NETDEV_UNREGISTER:
4176 packet_dev_mclist_delete(dev, &po->mclist);
4180 if (dev->ifindex == po->ifindex) {
4181 spin_lock(&po->bind_lock);
4182 if (packet_sock_flag(po, PACKET_SOCK_RUNNING)) {
4183 __unregister_prot_hook(sk, false);
4184 sk->sk_err = ENETDOWN;
4185 if (!sock_flag(sk, SOCK_DEAD))
4186 sk_error_report(sk);
4188 if (msg == NETDEV_UNREGISTER) {
4189 packet_cached_dev_reset(po);
4190 WRITE_ONCE(po->ifindex, -1);
4191 netdev_put(po->prot_hook.dev,
4192 &po->prot_hook.dev_tracker);
4193 po->prot_hook.dev = NULL;
4195 spin_unlock(&po->bind_lock);
4199 if (dev->ifindex == po->ifindex) {
4200 spin_lock(&po->bind_lock);
4202 register_prot_hook(sk);
4203 spin_unlock(&po->bind_lock);
4213 static int packet_ioctl(struct socket *sock, unsigned int cmd,
4216 struct sock *sk = sock->sk;
4221 int amount = sk_wmem_alloc_get(sk);
4223 return put_user(amount, (int __user *)arg);
4227 struct sk_buff *skb;
4230 spin_lock_bh(&sk->sk_receive_queue.lock);
4231 skb = skb_peek(&sk->sk_receive_queue);
4234 spin_unlock_bh(&sk->sk_receive_queue.lock);
4235 return put_user(amount, (int __user *)arg);
4245 case SIOCGIFBRDADDR:
4246 case SIOCSIFBRDADDR:
4247 case SIOCGIFNETMASK:
4248 case SIOCSIFNETMASK:
4249 case SIOCGIFDSTADDR:
4250 case SIOCSIFDSTADDR:
4252 return inet_dgram_ops.ioctl(sock, cmd, arg);
4256 return -ENOIOCTLCMD;
4261 static __poll_t packet_poll(struct file *file, struct socket *sock,
4264 struct sock *sk = sock->sk;
4265 struct packet_sock *po = pkt_sk(sk);
4266 __poll_t mask = datagram_poll(file, sock, wait);
4268 spin_lock_bh(&sk->sk_receive_queue.lock);
4269 if (po->rx_ring.pg_vec) {
4270 if (!packet_previous_rx_frame(po, &po->rx_ring,
4272 mask |= EPOLLIN | EPOLLRDNORM;
4274 packet_rcv_try_clear_pressure(po);
4275 spin_unlock_bh(&sk->sk_receive_queue.lock);
4276 spin_lock_bh(&sk->sk_write_queue.lock);
4277 if (po->tx_ring.pg_vec) {
4278 if (packet_current_frame(po, &po->tx_ring, TP_STATUS_AVAILABLE))
4279 mask |= EPOLLOUT | EPOLLWRNORM;
4281 spin_unlock_bh(&sk->sk_write_queue.lock);
4286 /* Dirty? Well, I still did not learn better way to account
4290 static void packet_mm_open(struct vm_area_struct *vma)
4292 struct file *file = vma->vm_file;
4293 struct socket *sock = file->private_data;
4294 struct sock *sk = sock->sk;
4297 atomic_long_inc(&pkt_sk(sk)->mapped);
4300 static void packet_mm_close(struct vm_area_struct *vma)
4302 struct file *file = vma->vm_file;
4303 struct socket *sock = file->private_data;
4304 struct sock *sk = sock->sk;
4307 atomic_long_dec(&pkt_sk(sk)->mapped);
4310 static const struct vm_operations_struct packet_mmap_ops = {
4311 .open = packet_mm_open,
4312 .close = packet_mm_close,
4315 static void free_pg_vec(struct pgv *pg_vec, unsigned int order,
4320 for (i = 0; i < len; i++) {
4321 if (likely(pg_vec[i].buffer)) {
4322 if (is_vmalloc_addr(pg_vec[i].buffer))
4323 vfree(pg_vec[i].buffer);
4325 free_pages((unsigned long)pg_vec[i].buffer,
4327 pg_vec[i].buffer = NULL;
4333 static char *alloc_one_pg_vec_page(unsigned long order)
4336 gfp_t gfp_flags = GFP_KERNEL | __GFP_COMP |
4337 __GFP_ZERO | __GFP_NOWARN | __GFP_NORETRY;
4339 buffer = (char *) __get_free_pages(gfp_flags, order);
4343 /* __get_free_pages failed, fall back to vmalloc */
4344 buffer = vzalloc(array_size((1 << order), PAGE_SIZE));
4348 /* vmalloc failed, lets dig into swap here */
4349 gfp_flags &= ~__GFP_NORETRY;
4350 buffer = (char *) __get_free_pages(gfp_flags, order);
4354 /* complete and utter failure */
4358 static struct pgv *alloc_pg_vec(struct tpacket_req *req, int order)
4360 unsigned int block_nr = req->tp_block_nr;
4364 pg_vec = kcalloc(block_nr, sizeof(struct pgv), GFP_KERNEL | __GFP_NOWARN);
4365 if (unlikely(!pg_vec))
4368 for (i = 0; i < block_nr; i++) {
4369 pg_vec[i].buffer = alloc_one_pg_vec_page(order);
4370 if (unlikely(!pg_vec[i].buffer))
4371 goto out_free_pgvec;
4378 free_pg_vec(pg_vec, order, block_nr);
4383 static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
4384 int closing, int tx_ring)
4386 struct pgv *pg_vec = NULL;
4387 struct packet_sock *po = pkt_sk(sk);
4388 unsigned long *rx_owner_map = NULL;
4389 int was_running, order = 0;
4390 struct packet_ring_buffer *rb;
4391 struct sk_buff_head *rb_queue;
4394 /* Added to avoid minimal code churn */
4395 struct tpacket_req *req = &req_u->req;
4397 rb = tx_ring ? &po->tx_ring : &po->rx_ring;
4398 rb_queue = tx_ring ? &sk->sk_write_queue : &sk->sk_receive_queue;
4402 if (atomic_long_read(&po->mapped))
4404 if (packet_read_pending(rb))
4408 if (req->tp_block_nr) {
4409 unsigned int min_frame_size;
4411 /* Sanity tests and some calculations */
4413 if (unlikely(rb->pg_vec))
4416 switch (po->tp_version) {
4418 po->tp_hdrlen = TPACKET_HDRLEN;
4421 po->tp_hdrlen = TPACKET2_HDRLEN;
4424 po->tp_hdrlen = TPACKET3_HDRLEN;
4429 if (unlikely((int)req->tp_block_size <= 0))
4431 if (unlikely(!PAGE_ALIGNED(req->tp_block_size)))
4433 min_frame_size = po->tp_hdrlen + po->tp_reserve;
4434 if (po->tp_version >= TPACKET_V3 &&
4435 req->tp_block_size <
4436 BLK_PLUS_PRIV((u64)req_u->req3.tp_sizeof_priv) + min_frame_size)
4438 if (unlikely(req->tp_frame_size < min_frame_size))
4440 if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
4443 rb->frames_per_block = req->tp_block_size / req->tp_frame_size;
4444 if (unlikely(rb->frames_per_block == 0))
4446 if (unlikely(rb->frames_per_block > UINT_MAX / req->tp_block_nr))
4448 if (unlikely((rb->frames_per_block * req->tp_block_nr) !=
4453 order = get_order(req->tp_block_size);
4454 pg_vec = alloc_pg_vec(req, order);
4455 if (unlikely(!pg_vec))
4457 switch (po->tp_version) {
4459 /* Block transmit is not supported yet */
4461 init_prb_bdqc(po, rb, pg_vec, req_u);
4463 struct tpacket_req3 *req3 = &req_u->req3;
4465 if (req3->tp_retire_blk_tov ||
4466 req3->tp_sizeof_priv ||
4467 req3->tp_feature_req_word) {
4469 goto out_free_pg_vec;
4475 rx_owner_map = bitmap_alloc(req->tp_frame_nr,
4476 GFP_KERNEL | __GFP_NOWARN | __GFP_ZERO);
4478 goto out_free_pg_vec;
4486 if (unlikely(req->tp_frame_nr))
4491 /* Detach socket from network */
4492 spin_lock(&po->bind_lock);
4493 was_running = packet_sock_flag(po, PACKET_SOCK_RUNNING);
4496 WRITE_ONCE(po->num, 0);
4497 __unregister_prot_hook(sk, false);
4499 spin_unlock(&po->bind_lock);
4504 mutex_lock(&po->pg_vec_lock);
4505 if (closing || atomic_long_read(&po->mapped) == 0) {
4507 spin_lock_bh(&rb_queue->lock);
4508 swap(rb->pg_vec, pg_vec);
4509 if (po->tp_version <= TPACKET_V2)
4510 swap(rb->rx_owner_map, rx_owner_map);
4511 rb->frame_max = (req->tp_frame_nr - 1);
4513 rb->frame_size = req->tp_frame_size;
4514 spin_unlock_bh(&rb_queue->lock);
4516 swap(rb->pg_vec_order, order);
4517 swap(rb->pg_vec_len, req->tp_block_nr);
4519 rb->pg_vec_pages = req->tp_block_size/PAGE_SIZE;
4520 po->prot_hook.func = (po->rx_ring.pg_vec) ?
4521 tpacket_rcv : packet_rcv;
4522 skb_queue_purge(rb_queue);
4523 if (atomic_long_read(&po->mapped))
4524 pr_err("packet_mmap: vma is busy: %ld\n",
4525 atomic_long_read(&po->mapped));
4527 mutex_unlock(&po->pg_vec_lock);
4529 spin_lock(&po->bind_lock);
4531 WRITE_ONCE(po->num, num);
4532 register_prot_hook(sk);
4534 spin_unlock(&po->bind_lock);
4535 if (pg_vec && (po->tp_version > TPACKET_V2)) {
4536 /* Because we don't support block-based V3 on tx-ring */
4538 prb_shutdown_retire_blk_timer(po, rb_queue);
4543 bitmap_free(rx_owner_map);
4544 free_pg_vec(pg_vec, order, req->tp_block_nr);
4550 static int packet_mmap(struct file *file, struct socket *sock,
4551 struct vm_area_struct *vma)
4553 struct sock *sk = sock->sk;
4554 struct packet_sock *po = pkt_sk(sk);
4555 unsigned long size, expected_size;
4556 struct packet_ring_buffer *rb;
4557 unsigned long start;
4564 mutex_lock(&po->pg_vec_lock);
4567 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
4569 expected_size += rb->pg_vec_len
4575 if (expected_size == 0)
4578 size = vma->vm_end - vma->vm_start;
4579 if (size != expected_size)
4582 start = vma->vm_start;
4583 for (rb = &po->rx_ring; rb <= &po->tx_ring; rb++) {
4584 if (rb->pg_vec == NULL)
4587 for (i = 0; i < rb->pg_vec_len; i++) {
4589 void *kaddr = rb->pg_vec[i].buffer;
4592 for (pg_num = 0; pg_num < rb->pg_vec_pages; pg_num++) {
4593 page = pgv_to_page(kaddr);
4594 err = vm_insert_page(vma, start, page);
4603 atomic_long_inc(&po->mapped);
4604 vma->vm_ops = &packet_mmap_ops;
4608 mutex_unlock(&po->pg_vec_lock);
4612 static const struct proto_ops packet_ops_spkt = {
4613 .family = PF_PACKET,
4614 .owner = THIS_MODULE,
4615 .release = packet_release,
4616 .bind = packet_bind_spkt,
4617 .connect = sock_no_connect,
4618 .socketpair = sock_no_socketpair,
4619 .accept = sock_no_accept,
4620 .getname = packet_getname_spkt,
4621 .poll = datagram_poll,
4622 .ioctl = packet_ioctl,
4623 .gettstamp = sock_gettstamp,
4624 .listen = sock_no_listen,
4625 .shutdown = sock_no_shutdown,
4626 .sendmsg = packet_sendmsg_spkt,
4627 .recvmsg = packet_recvmsg,
4628 .mmap = sock_no_mmap,
4631 static const struct proto_ops packet_ops = {
4632 .family = PF_PACKET,
4633 .owner = THIS_MODULE,
4634 .release = packet_release,
4635 .bind = packet_bind,
4636 .connect = sock_no_connect,
4637 .socketpair = sock_no_socketpair,
4638 .accept = sock_no_accept,
4639 .getname = packet_getname,
4640 .poll = packet_poll,
4641 .ioctl = packet_ioctl,
4642 .gettstamp = sock_gettstamp,
4643 .listen = sock_no_listen,
4644 .shutdown = sock_no_shutdown,
4645 .setsockopt = packet_setsockopt,
4646 .getsockopt = packet_getsockopt,
4647 .sendmsg = packet_sendmsg,
4648 .recvmsg = packet_recvmsg,
4649 .mmap = packet_mmap,
4652 static const struct net_proto_family packet_family_ops = {
4653 .family = PF_PACKET,
4654 .create = packet_create,
4655 .owner = THIS_MODULE,
4658 static struct notifier_block packet_netdev_notifier = {
4659 .notifier_call = packet_notifier,
4662 #ifdef CONFIG_PROC_FS
4664 static void *packet_seq_start(struct seq_file *seq, loff_t *pos)
4667 struct net *net = seq_file_net(seq);
4670 return seq_hlist_start_head_rcu(&net->packet.sklist, *pos);
4673 static void *packet_seq_next(struct seq_file *seq, void *v, loff_t *pos)
4675 struct net *net = seq_file_net(seq);
4676 return seq_hlist_next_rcu(v, &net->packet.sklist, pos);
4679 static void packet_seq_stop(struct seq_file *seq, void *v)
4685 static int packet_seq_show(struct seq_file *seq, void *v)
4687 if (v == SEQ_START_TOKEN)
4689 "%*sRefCnt Type Proto Iface R Rmem User Inode\n",
4690 IS_ENABLED(CONFIG_64BIT) ? -17 : -9, "sk");
4692 struct sock *s = sk_entry(v);
4693 const struct packet_sock *po = pkt_sk(s);
4696 "%pK %-6d %-4d %04x %-5d %1d %-6u %-6u %-6lu\n",
4698 refcount_read(&s->sk_refcnt),
4700 ntohs(READ_ONCE(po->num)),
4701 READ_ONCE(po->ifindex),
4702 packet_sock_flag(po, PACKET_SOCK_RUNNING),
4703 atomic_read(&s->sk_rmem_alloc),
4704 from_kuid_munged(seq_user_ns(seq), sock_i_uid(s)),
4711 static const struct seq_operations packet_seq_ops = {
4712 .start = packet_seq_start,
4713 .next = packet_seq_next,
4714 .stop = packet_seq_stop,
4715 .show = packet_seq_show,
4719 static int __net_init packet_net_init(struct net *net)
4721 mutex_init(&net->packet.sklist_lock);
4722 INIT_HLIST_HEAD(&net->packet.sklist);
4724 #ifdef CONFIG_PROC_FS
4725 if (!proc_create_net("packet", 0, net->proc_net, &packet_seq_ops,
4726 sizeof(struct seq_net_private)))
4728 #endif /* CONFIG_PROC_FS */
4733 static void __net_exit packet_net_exit(struct net *net)
4735 remove_proc_entry("packet", net->proc_net);
4736 WARN_ON_ONCE(!hlist_empty(&net->packet.sklist));
4739 static struct pernet_operations packet_net_ops = {
4740 .init = packet_net_init,
4741 .exit = packet_net_exit,
4745 static void __exit packet_exit(void)
4747 sock_unregister(PF_PACKET);
4748 proto_unregister(&packet_proto);
4749 unregister_netdevice_notifier(&packet_netdev_notifier);
4750 unregister_pernet_subsys(&packet_net_ops);
4753 static int __init packet_init(void)
4757 rc = register_pernet_subsys(&packet_net_ops);
4760 rc = register_netdevice_notifier(&packet_netdev_notifier);
4763 rc = proto_register(&packet_proto, 0);
4766 rc = sock_register(&packet_family_ops);
4773 proto_unregister(&packet_proto);
4775 unregister_netdevice_notifier(&packet_netdev_notifier);
4777 unregister_pernet_subsys(&packet_net_ops);
4782 module_init(packet_init);
4783 module_exit(packet_exit);
4784 MODULE_DESCRIPTION("Packet socket support (AF_PACKET)");
4785 MODULE_LICENSE("GPL");
4786 MODULE_ALIAS_NETPROTO(PF_PACKET);