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 * The User Datagram Protocol (UDP).
10 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
11 * Arnt Gulbrandsen, <agulbra@nvg.unit.no>
12 * Alan Cox, <alan@lxorguk.ukuu.org.uk>
13 * Hirokazu Takahashi, <taka@valinux.co.jp>
16 * Alan Cox : verify_area() calls
17 * Alan Cox : stopped close while in use off icmp
18 * messages. Not a fix but a botch that
19 * for udp at least is 'valid'.
20 * Alan Cox : Fixed icmp handling properly
21 * Alan Cox : Correct error for oversized datagrams
22 * Alan Cox : Tidied select() semantics.
23 * Alan Cox : udp_err() fixed properly, also now
24 * select and read wake correctly on errors
25 * Alan Cox : udp_send verify_area moved to avoid mem leak
26 * Alan Cox : UDP can count its memory
27 * Alan Cox : send to an unknown connection causes
28 * an ECONNREFUSED off the icmp, but
30 * Alan Cox : Switched to new sk_buff handlers. No more backlog!
31 * Alan Cox : Using generic datagram code. Even smaller and the PEEK
32 * bug no longer crashes it.
33 * Fred Van Kempen : Net2e support for sk->broadcast.
34 * Alan Cox : Uses skb_free_datagram
35 * Alan Cox : Added get/set sockopt support.
36 * Alan Cox : Broadcasting without option set returns EACCES.
37 * Alan Cox : No wakeup calls. Instead we now use the callbacks.
38 * Alan Cox : Use ip_tos and ip_ttl
39 * Alan Cox : SNMP Mibs
40 * Alan Cox : MSG_DONTROUTE, and 0.0.0.0 support.
41 * Matt Dillon : UDP length checks.
42 * Alan Cox : Smarter af_inet used properly.
43 * Alan Cox : Use new kernel side addressing.
44 * Alan Cox : Incorrect return on truncated datagram receive.
45 * Arnt Gulbrandsen : New udp_send and stuff
46 * Alan Cox : Cache last socket
47 * Alan Cox : Route cache
48 * Jon Peatfield : Minor efficiency fix to sendto().
49 * Mike Shaver : RFC1122 checks.
50 * Alan Cox : Nonblocking error fix.
51 * Willy Konynenberg : Transparent proxying support.
52 * Mike McLagan : Routing by source
53 * David S. Miller : New socket lookup architecture.
54 * Last socket cache retained as it
55 * does have a high hit rate.
56 * Olaf Kirch : Don't linearise iovec on sendmsg.
57 * Andi Kleen : Some cleanups, cache destination entry
59 * Vitaly E. Lavrov : Transparent proxy revived after year coma.
60 * Melvin Smith : Check msg_name not msg_namelen in sendto(),
61 * return ENOTCONN for unconnected sockets (POSIX)
62 * Janos Farkas : don't deliver multi/broadcasts to a different
63 * bound-to-device socket
64 * Hirokazu Takahashi : HW checksumming for outgoing UDP
66 * Hirokazu Takahashi : sendfile() on UDP works now.
67 * Arnaldo C. Melo : convert /proc/net/udp to seq_file
68 * YOSHIFUJI Hideaki @USAGI and: Support IPV6_V6ONLY socket option, which
69 * Alexey Kuznetsov: allow both IPv4 and IPv6 sockets to bind
70 * a single port at the same time.
71 * Derek Atkins <derek@ihtfp.com>: Add Encapulation Support
72 * James Chapman : Add L2TP encapsulation type.
75 #define pr_fmt(fmt) "UDP: " fmt
77 #include <linux/uaccess.h>
78 #include <asm/ioctls.h>
79 #include <linux/memblock.h>
80 #include <linux/highmem.h>
81 #include <linux/swap.h>
82 #include <linux/types.h>
83 #include <linux/fcntl.h>
84 #include <linux/module.h>
85 #include <linux/socket.h>
86 #include <linux/sockios.h>
87 #include <linux/igmp.h>
88 #include <linux/inetdevice.h>
90 #include <linux/errno.h>
91 #include <linux/timer.h>
93 #include <linux/inet.h>
94 #include <linux/netdevice.h>
95 #include <linux/slab.h>
96 #include <net/tcp_states.h>
97 #include <linux/skbuff.h>
98 #include <linux/proc_fs.h>
99 #include <linux/seq_file.h>
100 #include <net/net_namespace.h>
101 #include <net/icmp.h>
102 #include <net/inet_hashtables.h>
103 #include <net/ip_tunnels.h>
104 #include <net/route.h>
105 #include <net/checksum.h>
106 #include <net/xfrm.h>
107 #include <trace/events/udp.h>
108 #include <linux/static_key.h>
109 #include <trace/events/skb.h>
110 #include <net/busy_poll.h>
111 #include "udp_impl.h"
112 #include <net/sock_reuseport.h>
113 #include <net/addrconf.h>
114 #include <net/udp_tunnel.h>
116 struct udp_table udp_table __read_mostly
;
117 EXPORT_SYMBOL(udp_table
);
119 long sysctl_udp_mem
[3] __read_mostly
;
120 EXPORT_SYMBOL(sysctl_udp_mem
);
122 atomic_long_t udp_memory_allocated
;
123 EXPORT_SYMBOL(udp_memory_allocated
);
125 #define MAX_UDP_PORTS 65536
126 #define PORTS_PER_CHAIN (MAX_UDP_PORTS / UDP_HTABLE_SIZE_MIN)
128 static int udp_lib_lport_inuse(struct net
*net
, __u16 num
,
129 const struct udp_hslot
*hslot
,
130 unsigned long *bitmap
,
131 struct sock
*sk
, unsigned int log
)
134 kuid_t uid
= sock_i_uid(sk
);
136 sk_for_each(sk2
, &hslot
->head
) {
137 if (net_eq(sock_net(sk2
), net
) &&
139 (bitmap
|| udp_sk(sk2
)->udp_port_hash
== num
) &&
140 (!sk2
->sk_reuse
|| !sk
->sk_reuse
) &&
141 (!sk2
->sk_bound_dev_if
|| !sk
->sk_bound_dev_if
||
142 sk2
->sk_bound_dev_if
== sk
->sk_bound_dev_if
) &&
143 inet_rcv_saddr_equal(sk
, sk2
, true)) {
144 if (sk2
->sk_reuseport
&& sk
->sk_reuseport
&&
145 !rcu_access_pointer(sk
->sk_reuseport_cb
) &&
146 uid_eq(uid
, sock_i_uid(sk2
))) {
152 __set_bit(udp_sk(sk2
)->udp_port_hash
>> log
,
161 * Note: we still hold spinlock of primary hash chain, so no other writer
162 * can insert/delete a socket with local_port == num
164 static int udp_lib_lport_inuse2(struct net
*net
, __u16 num
,
165 struct udp_hslot
*hslot2
,
169 kuid_t uid
= sock_i_uid(sk
);
172 spin_lock(&hslot2
->lock
);
173 udp_portaddr_for_each_entry(sk2
, &hslot2
->head
) {
174 if (net_eq(sock_net(sk2
), net
) &&
176 (udp_sk(sk2
)->udp_port_hash
== num
) &&
177 (!sk2
->sk_reuse
|| !sk
->sk_reuse
) &&
178 (!sk2
->sk_bound_dev_if
|| !sk
->sk_bound_dev_if
||
179 sk2
->sk_bound_dev_if
== sk
->sk_bound_dev_if
) &&
180 inet_rcv_saddr_equal(sk
, sk2
, true)) {
181 if (sk2
->sk_reuseport
&& sk
->sk_reuseport
&&
182 !rcu_access_pointer(sk
->sk_reuseport_cb
) &&
183 uid_eq(uid
, sock_i_uid(sk2
))) {
191 spin_unlock(&hslot2
->lock
);
195 static int udp_reuseport_add_sock(struct sock
*sk
, struct udp_hslot
*hslot
)
197 struct net
*net
= sock_net(sk
);
198 kuid_t uid
= sock_i_uid(sk
);
201 sk_for_each(sk2
, &hslot
->head
) {
202 if (net_eq(sock_net(sk2
), net
) &&
204 sk2
->sk_family
== sk
->sk_family
&&
205 ipv6_only_sock(sk2
) == ipv6_only_sock(sk
) &&
206 (udp_sk(sk2
)->udp_port_hash
== udp_sk(sk
)->udp_port_hash
) &&
207 (sk2
->sk_bound_dev_if
== sk
->sk_bound_dev_if
) &&
208 sk2
->sk_reuseport
&& uid_eq(uid
, sock_i_uid(sk2
)) &&
209 inet_rcv_saddr_equal(sk
, sk2
, false)) {
210 return reuseport_add_sock(sk
, sk2
,
211 inet_rcv_saddr_any(sk
));
215 return reuseport_alloc(sk
, inet_rcv_saddr_any(sk
));
219 * udp_lib_get_port - UDP/-Lite port lookup for IPv4 and IPv6
221 * @sk: socket struct in question
222 * @snum: port number to look up
223 * @hash2_nulladdr: AF-dependent hash value in secondary hash chains,
226 int udp_lib_get_port(struct sock
*sk
, unsigned short snum
,
227 unsigned int hash2_nulladdr
)
229 struct udp_hslot
*hslot
, *hslot2
;
230 struct udp_table
*udptable
= sk
->sk_prot
->h
.udp_table
;
232 struct net
*net
= sock_net(sk
);
235 int low
, high
, remaining
;
237 unsigned short first
, last
;
238 DECLARE_BITMAP(bitmap
, PORTS_PER_CHAIN
);
240 inet_get_local_port_range(net
, &low
, &high
);
241 remaining
= (high
- low
) + 1;
243 rand
= prandom_u32();
244 first
= reciprocal_scale(rand
, remaining
) + low
;
246 * force rand to be an odd multiple of UDP_HTABLE_SIZE
248 rand
= (rand
| 1) * (udptable
->mask
+ 1);
249 last
= first
+ udptable
->mask
+ 1;
251 hslot
= udp_hashslot(udptable
, net
, first
);
252 bitmap_zero(bitmap
, PORTS_PER_CHAIN
);
253 spin_lock_bh(&hslot
->lock
);
254 udp_lib_lport_inuse(net
, snum
, hslot
, bitmap
, sk
,
259 * Iterate on all possible values of snum for this hash.
260 * Using steps of an odd multiple of UDP_HTABLE_SIZE
261 * give us randomization and full range coverage.
264 if (low
<= snum
&& snum
<= high
&&
265 !test_bit(snum
>> udptable
->log
, bitmap
) &&
266 !inet_is_local_reserved_port(net
, snum
))
269 } while (snum
!= first
);
270 spin_unlock_bh(&hslot
->lock
);
272 } while (++first
!= last
);
275 hslot
= udp_hashslot(udptable
, net
, snum
);
276 spin_lock_bh(&hslot
->lock
);
277 if (hslot
->count
> 10) {
279 unsigned int slot2
= udp_sk(sk
)->udp_portaddr_hash
^ snum
;
281 slot2
&= udptable
->mask
;
282 hash2_nulladdr
&= udptable
->mask
;
284 hslot2
= udp_hashslot2(udptable
, slot2
);
285 if (hslot
->count
< hslot2
->count
)
286 goto scan_primary_hash
;
288 exist
= udp_lib_lport_inuse2(net
, snum
, hslot2
, sk
);
289 if (!exist
&& (hash2_nulladdr
!= slot2
)) {
290 hslot2
= udp_hashslot2(udptable
, hash2_nulladdr
);
291 exist
= udp_lib_lport_inuse2(net
, snum
, hslot2
,
300 if (udp_lib_lport_inuse(net
, snum
, hslot
, NULL
, sk
, 0))
304 inet_sk(sk
)->inet_num
= snum
;
305 udp_sk(sk
)->udp_port_hash
= snum
;
306 udp_sk(sk
)->udp_portaddr_hash
^= snum
;
307 if (sk_unhashed(sk
)) {
308 if (sk
->sk_reuseport
&&
309 udp_reuseport_add_sock(sk
, hslot
)) {
310 inet_sk(sk
)->inet_num
= 0;
311 udp_sk(sk
)->udp_port_hash
= 0;
312 udp_sk(sk
)->udp_portaddr_hash
^= snum
;
316 sk_add_node_rcu(sk
, &hslot
->head
);
318 sock_prot_inuse_add(sock_net(sk
), sk
->sk_prot
, 1);
320 hslot2
= udp_hashslot2(udptable
, udp_sk(sk
)->udp_portaddr_hash
);
321 spin_lock(&hslot2
->lock
);
322 if (IS_ENABLED(CONFIG_IPV6
) && sk
->sk_reuseport
&&
323 sk
->sk_family
== AF_INET6
)
324 hlist_add_tail_rcu(&udp_sk(sk
)->udp_portaddr_node
,
327 hlist_add_head_rcu(&udp_sk(sk
)->udp_portaddr_node
,
330 spin_unlock(&hslot2
->lock
);
332 sock_set_flag(sk
, SOCK_RCU_FREE
);
335 spin_unlock_bh(&hslot
->lock
);
339 EXPORT_SYMBOL(udp_lib_get_port
);
341 int udp_v4_get_port(struct sock
*sk
, unsigned short snum
)
343 unsigned int hash2_nulladdr
=
344 ipv4_portaddr_hash(sock_net(sk
), htonl(INADDR_ANY
), snum
);
345 unsigned int hash2_partial
=
346 ipv4_portaddr_hash(sock_net(sk
), inet_sk(sk
)->inet_rcv_saddr
, 0);
348 /* precompute partial secondary hash */
349 udp_sk(sk
)->udp_portaddr_hash
= hash2_partial
;
350 return udp_lib_get_port(sk
, snum
, hash2_nulladdr
);
353 static int compute_score(struct sock
*sk
, struct net
*net
,
354 __be32 saddr
, __be16 sport
,
355 __be32 daddr
, unsigned short hnum
,
359 struct inet_sock
*inet
;
362 if (!net_eq(sock_net(sk
), net
) ||
363 udp_sk(sk
)->udp_port_hash
!= hnum
||
367 if (sk
->sk_rcv_saddr
!= daddr
)
370 score
= (sk
->sk_family
== PF_INET
) ? 2 : 1;
373 if (inet
->inet_daddr
) {
374 if (inet
->inet_daddr
!= saddr
)
379 if (inet
->inet_dport
) {
380 if (inet
->inet_dport
!= sport
)
385 dev_match
= udp_sk_bound_dev_eq(net
, sk
->sk_bound_dev_if
,
391 if (sk
->sk_incoming_cpu
== raw_smp_processor_id())
396 static u32
udp_ehashfn(const struct net
*net
, const __be32 laddr
,
397 const __u16 lport
, const __be32 faddr
,
400 static u32 udp_ehash_secret __read_mostly
;
402 net_get_random_once(&udp_ehash_secret
, sizeof(udp_ehash_secret
));
404 return __inet_ehashfn(laddr
, lport
, faddr
, fport
,
405 udp_ehash_secret
+ net_hash_mix(net
));
408 /* called with rcu_read_lock() */
409 static struct sock
*udp4_lib_lookup2(struct net
*net
,
410 __be32 saddr
, __be16 sport
,
411 __be32 daddr
, unsigned int hnum
,
413 struct udp_hslot
*hslot2
,
416 struct sock
*sk
, *result
;
422 udp_portaddr_for_each_entry_rcu(sk
, &hslot2
->head
) {
423 score
= compute_score(sk
, net
, saddr
, sport
,
424 daddr
, hnum
, dif
, sdif
);
425 if (score
> badness
) {
426 if (sk
->sk_reuseport
) {
427 hash
= udp_ehashfn(net
, daddr
, hnum
,
429 result
= reuseport_select_sock(sk
, hash
, skb
,
430 sizeof(struct udphdr
));
441 /* UDP is nearly always wildcards out the wazoo, it makes no sense to try
442 * harder than this. -DaveM
444 struct sock
*__udp4_lib_lookup(struct net
*net
, __be32 saddr
,
445 __be16 sport
, __be32 daddr
, __be16 dport
, int dif
,
446 int sdif
, struct udp_table
*udptable
, struct sk_buff
*skb
)
449 unsigned short hnum
= ntohs(dport
);
450 unsigned int hash2
, slot2
;
451 struct udp_hslot
*hslot2
;
453 hash2
= ipv4_portaddr_hash(net
, daddr
, hnum
);
454 slot2
= hash2
& udptable
->mask
;
455 hslot2
= &udptable
->hash2
[slot2
];
457 result
= udp4_lib_lookup2(net
, saddr
, sport
,
458 daddr
, hnum
, dif
, sdif
,
461 hash2
= ipv4_portaddr_hash(net
, htonl(INADDR_ANY
), hnum
);
462 slot2
= hash2
& udptable
->mask
;
463 hslot2
= &udptable
->hash2
[slot2
];
465 result
= udp4_lib_lookup2(net
, saddr
, sport
,
466 htonl(INADDR_ANY
), hnum
, dif
, sdif
,
473 EXPORT_SYMBOL_GPL(__udp4_lib_lookup
);
475 static inline struct sock
*__udp4_lib_lookup_skb(struct sk_buff
*skb
,
476 __be16 sport
, __be16 dport
,
477 struct udp_table
*udptable
)
479 const struct iphdr
*iph
= ip_hdr(skb
);
481 return __udp4_lib_lookup(dev_net(skb
->dev
), iph
->saddr
, sport
,
482 iph
->daddr
, dport
, inet_iif(skb
),
483 inet_sdif(skb
), udptable
, skb
);
486 struct sock
*udp4_lib_lookup_skb(struct sk_buff
*skb
,
487 __be16 sport
, __be16 dport
)
489 const struct iphdr
*iph
= ip_hdr(skb
);
491 return __udp4_lib_lookup(dev_net(skb
->dev
), iph
->saddr
, sport
,
492 iph
->daddr
, dport
, inet_iif(skb
),
493 inet_sdif(skb
), &udp_table
, NULL
);
495 EXPORT_SYMBOL_GPL(udp4_lib_lookup_skb
);
497 /* Must be called under rcu_read_lock().
498 * Does increment socket refcount.
500 #if IS_ENABLED(CONFIG_NF_TPROXY_IPV4) || IS_ENABLED(CONFIG_NF_SOCKET_IPV4)
501 struct sock
*udp4_lib_lookup(struct net
*net
, __be32 saddr
, __be16 sport
,
502 __be32 daddr
, __be16 dport
, int dif
)
506 sk
= __udp4_lib_lookup(net
, saddr
, sport
, daddr
, dport
,
507 dif
, 0, &udp_table
, NULL
);
508 if (sk
&& !refcount_inc_not_zero(&sk
->sk_refcnt
))
512 EXPORT_SYMBOL_GPL(udp4_lib_lookup
);
515 static inline bool __udp_is_mcast_sock(struct net
*net
, struct sock
*sk
,
516 __be16 loc_port
, __be32 loc_addr
,
517 __be16 rmt_port
, __be32 rmt_addr
,
518 int dif
, int sdif
, unsigned short hnum
)
520 struct inet_sock
*inet
= inet_sk(sk
);
522 if (!net_eq(sock_net(sk
), net
) ||
523 udp_sk(sk
)->udp_port_hash
!= hnum
||
524 (inet
->inet_daddr
&& inet
->inet_daddr
!= rmt_addr
) ||
525 (inet
->inet_dport
!= rmt_port
&& inet
->inet_dport
) ||
526 (inet
->inet_rcv_saddr
&& inet
->inet_rcv_saddr
!= loc_addr
) ||
527 ipv6_only_sock(sk
) ||
528 !udp_sk_bound_dev_eq(net
, sk
->sk_bound_dev_if
, dif
, sdif
))
530 if (!ip_mc_sf_allow(sk
, loc_addr
, rmt_addr
, dif
, sdif
))
535 DEFINE_STATIC_KEY_FALSE(udp_encap_needed_key
);
536 void udp_encap_enable(void)
538 static_branch_inc(&udp_encap_needed_key
);
540 EXPORT_SYMBOL(udp_encap_enable
);
542 /* Handler for tunnels with arbitrary destination ports: no socket lookup, go
543 * through error handlers in encapsulations looking for a match.
545 static int __udp4_lib_err_encap_no_sk(struct sk_buff
*skb
, u32 info
)
549 for (i
= 0; i
< MAX_IPTUN_ENCAP_OPS
; i
++) {
550 int (*handler
)(struct sk_buff
*skb
, u32 info
);
551 const struct ip_tunnel_encap_ops
*encap
;
553 encap
= rcu_dereference(iptun_encaps
[i
]);
556 handler
= encap
->err_handler
;
557 if (handler
&& !handler(skb
, info
))
564 /* Try to match ICMP errors to UDP tunnels by looking up a socket without
565 * reversing source and destination port: this will match tunnels that force the
566 * same destination port on both endpoints (e.g. VXLAN, GENEVE). Note that
567 * lwtunnels might actually break this assumption by being configured with
568 * different destination ports on endpoints, in this case we won't be able to
569 * trace ICMP messages back to them.
571 * If this doesn't match any socket, probe tunnels with arbitrary destination
572 * ports (e.g. FoU, GUE): there, the receiving socket is useless, as the port
573 * we've sent packets to won't necessarily match the local destination port.
575 * Then ask the tunnel implementation to match the error against a valid
578 * Return an error if we can't find a match, the socket if we need further
579 * processing, zero otherwise.
581 static struct sock
*__udp4_lib_err_encap(struct net
*net
,
582 const struct iphdr
*iph
,
584 struct udp_table
*udptable
,
585 struct sk_buff
*skb
, u32 info
)
587 int network_offset
, transport_offset
;
590 network_offset
= skb_network_offset(skb
);
591 transport_offset
= skb_transport_offset(skb
);
593 /* Network header needs to point to the outer IPv4 header inside ICMP */
594 skb_reset_network_header(skb
);
596 /* Transport header needs to point to the UDP header */
597 skb_set_transport_header(skb
, iph
->ihl
<< 2);
599 sk
= __udp4_lib_lookup(net
, iph
->daddr
, uh
->source
,
600 iph
->saddr
, uh
->dest
, skb
->dev
->ifindex
, 0,
603 int (*lookup
)(struct sock
*sk
, struct sk_buff
*skb
);
604 struct udp_sock
*up
= udp_sk(sk
);
606 lookup
= READ_ONCE(up
->encap_err_lookup
);
607 if (!lookup
|| lookup(sk
, skb
))
612 sk
= ERR_PTR(__udp4_lib_err_encap_no_sk(skb
, info
));
614 skb_set_transport_header(skb
, transport_offset
);
615 skb_set_network_header(skb
, network_offset
);
621 * This routine is called by the ICMP module when it gets some
622 * sort of error condition. If err < 0 then the socket should
623 * be closed and the error returned to the user. If err > 0
624 * it's just the icmp type << 8 | icmp code.
625 * Header points to the ip header of the error packet. We move
626 * on past this. Then (as it used to claim before adjustment)
627 * header points to the first 8 bytes of the udp header. We need
628 * to find the appropriate port.
631 int __udp4_lib_err(struct sk_buff
*skb
, u32 info
, struct udp_table
*udptable
)
633 struct inet_sock
*inet
;
634 const struct iphdr
*iph
= (const struct iphdr
*)skb
->data
;
635 struct udphdr
*uh
= (struct udphdr
*)(skb
->data
+(iph
->ihl
<<2));
636 const int type
= icmp_hdr(skb
)->type
;
637 const int code
= icmp_hdr(skb
)->code
;
642 struct net
*net
= dev_net(skb
->dev
);
644 sk
= __udp4_lib_lookup(net
, iph
->daddr
, uh
->dest
,
645 iph
->saddr
, uh
->source
, skb
->dev
->ifindex
,
646 inet_sdif(skb
), udptable
, NULL
);
648 /* No socket for error: try tunnels before discarding */
649 sk
= ERR_PTR(-ENOENT
);
650 if (static_branch_unlikely(&udp_encap_needed_key
)) {
651 sk
= __udp4_lib_err_encap(net
, iph
, uh
, udptable
, skb
,
658 __ICMP_INC_STATS(net
, ICMP_MIB_INERRORS
);
671 case ICMP_TIME_EXCEEDED
:
674 case ICMP_SOURCE_QUENCH
:
676 case ICMP_PARAMETERPROB
:
680 case ICMP_DEST_UNREACH
:
681 if (code
== ICMP_FRAG_NEEDED
) { /* Path MTU discovery */
682 ipv4_sk_update_pmtu(skb
, sk
, info
);
683 if (inet
->pmtudisc
!= IP_PMTUDISC_DONT
) {
691 if (code
<= NR_ICMP_UNREACH
) {
692 harderr
= icmp_err_convert
[code
].fatal
;
693 err
= icmp_err_convert
[code
].errno
;
697 ipv4_sk_redirect(skb
, sk
);
702 * RFC1122: OK. Passes ICMP errors back to application, as per
706 /* ...not for tunnels though: we don't have a sending socket */
709 if (!inet
->recverr
) {
710 if (!harderr
|| sk
->sk_state
!= TCP_ESTABLISHED
)
713 ip_icmp_error(sk
, skb
, err
, uh
->dest
, info
, (u8
*)(uh
+1));
716 sk
->sk_error_report(sk
);
721 int udp_err(struct sk_buff
*skb
, u32 info
)
723 return __udp4_lib_err(skb
, info
, &udp_table
);
727 * Throw away all pending data and cancel the corking. Socket is locked.
729 void udp_flush_pending_frames(struct sock
*sk
)
731 struct udp_sock
*up
= udp_sk(sk
);
736 ip_flush_pending_frames(sk
);
739 EXPORT_SYMBOL(udp_flush_pending_frames
);
742 * udp4_hwcsum - handle outgoing HW checksumming
743 * @skb: sk_buff containing the filled-in UDP header
744 * (checksum field must be zeroed out)
745 * @src: source IP address
746 * @dst: destination IP address
748 void udp4_hwcsum(struct sk_buff
*skb
, __be32 src
, __be32 dst
)
750 struct udphdr
*uh
= udp_hdr(skb
);
751 int offset
= skb_transport_offset(skb
);
752 int len
= skb
->len
- offset
;
756 if (!skb_has_frag_list(skb
)) {
758 * Only one fragment on the socket.
760 skb
->csum_start
= skb_transport_header(skb
) - skb
->head
;
761 skb
->csum_offset
= offsetof(struct udphdr
, check
);
762 uh
->check
= ~csum_tcpudp_magic(src
, dst
, len
,
765 struct sk_buff
*frags
;
768 * HW-checksum won't work as there are two or more
769 * fragments on the socket so that all csums of sk_buffs
772 skb_walk_frags(skb
, frags
) {
773 csum
= csum_add(csum
, frags
->csum
);
777 csum
= skb_checksum(skb
, offset
, hlen
, csum
);
778 skb
->ip_summed
= CHECKSUM_NONE
;
780 uh
->check
= csum_tcpudp_magic(src
, dst
, len
, IPPROTO_UDP
, csum
);
782 uh
->check
= CSUM_MANGLED_0
;
785 EXPORT_SYMBOL_GPL(udp4_hwcsum
);
787 /* Function to set UDP checksum for an IPv4 UDP packet. This is intended
788 * for the simple case like when setting the checksum for a UDP tunnel.
790 void udp_set_csum(bool nocheck
, struct sk_buff
*skb
,
791 __be32 saddr
, __be32 daddr
, int len
)
793 struct udphdr
*uh
= udp_hdr(skb
);
797 } else if (skb_is_gso(skb
)) {
798 uh
->check
= ~udp_v4_check(len
, saddr
, daddr
, 0);
799 } else if (skb
->ip_summed
== CHECKSUM_PARTIAL
) {
801 uh
->check
= udp_v4_check(len
, saddr
, daddr
, lco_csum(skb
));
803 uh
->check
= CSUM_MANGLED_0
;
805 skb
->ip_summed
= CHECKSUM_PARTIAL
;
806 skb
->csum_start
= skb_transport_header(skb
) - skb
->head
;
807 skb
->csum_offset
= offsetof(struct udphdr
, check
);
808 uh
->check
= ~udp_v4_check(len
, saddr
, daddr
, 0);
811 EXPORT_SYMBOL(udp_set_csum
);
813 static int udp_send_skb(struct sk_buff
*skb
, struct flowi4
*fl4
,
814 struct inet_cork
*cork
)
816 struct sock
*sk
= skb
->sk
;
817 struct inet_sock
*inet
= inet_sk(sk
);
820 int is_udplite
= IS_UDPLITE(sk
);
821 int offset
= skb_transport_offset(skb
);
822 int len
= skb
->len
- offset
;
826 * Create a UDP header
829 uh
->source
= inet
->inet_sport
;
830 uh
->dest
= fl4
->fl4_dport
;
831 uh
->len
= htons(len
);
834 if (cork
->gso_size
) {
835 const int hlen
= skb_network_header_len(skb
) +
836 sizeof(struct udphdr
);
838 if (hlen
+ cork
->gso_size
> cork
->fragsize
) {
842 if (skb
->len
> cork
->gso_size
* UDP_MAX_SEGMENTS
) {
846 if (sk
->sk_no_check_tx
) {
850 if (skb
->ip_summed
!= CHECKSUM_PARTIAL
|| is_udplite
||
851 dst_xfrm(skb_dst(skb
))) {
856 skb_shinfo(skb
)->gso_size
= cork
->gso_size
;
857 skb_shinfo(skb
)->gso_type
= SKB_GSO_UDP_L4
;
858 skb_shinfo(skb
)->gso_segs
= DIV_ROUND_UP(len
- sizeof(uh
),
863 if (is_udplite
) /* UDP-Lite */
864 csum
= udplite_csum(skb
);
866 else if (sk
->sk_no_check_tx
) { /* UDP csum off */
868 skb
->ip_summed
= CHECKSUM_NONE
;
871 } else if (skb
->ip_summed
== CHECKSUM_PARTIAL
) { /* UDP hardware csum */
874 udp4_hwcsum(skb
, fl4
->saddr
, fl4
->daddr
);
878 csum
= udp_csum(skb
);
880 /* add protocol-dependent pseudo-header */
881 uh
->check
= csum_tcpudp_magic(fl4
->saddr
, fl4
->daddr
, len
,
882 sk
->sk_protocol
, csum
);
884 uh
->check
= CSUM_MANGLED_0
;
887 err
= ip_send_skb(sock_net(sk
), skb
);
889 if (err
== -ENOBUFS
&& !inet
->recverr
) {
890 UDP_INC_STATS(sock_net(sk
),
891 UDP_MIB_SNDBUFERRORS
, is_udplite
);
895 UDP_INC_STATS(sock_net(sk
),
896 UDP_MIB_OUTDATAGRAMS
, is_udplite
);
901 * Push out all pending data as one UDP datagram. Socket is locked.
903 int udp_push_pending_frames(struct sock
*sk
)
905 struct udp_sock
*up
= udp_sk(sk
);
906 struct inet_sock
*inet
= inet_sk(sk
);
907 struct flowi4
*fl4
= &inet
->cork
.fl
.u
.ip4
;
911 skb
= ip_finish_skb(sk
, fl4
);
915 err
= udp_send_skb(skb
, fl4
, &inet
->cork
.base
);
922 EXPORT_SYMBOL(udp_push_pending_frames
);
924 static int __udp_cmsg_send(struct cmsghdr
*cmsg
, u16
*gso_size
)
926 switch (cmsg
->cmsg_type
) {
928 if (cmsg
->cmsg_len
!= CMSG_LEN(sizeof(__u16
)))
930 *gso_size
= *(__u16
*)CMSG_DATA(cmsg
);
937 int udp_cmsg_send(struct sock
*sk
, struct msghdr
*msg
, u16
*gso_size
)
939 struct cmsghdr
*cmsg
;
940 bool need_ip
= false;
943 for_each_cmsghdr(cmsg
, msg
) {
944 if (!CMSG_OK(msg
, cmsg
))
947 if (cmsg
->cmsg_level
!= SOL_UDP
) {
952 err
= __udp_cmsg_send(cmsg
, gso_size
);
959 EXPORT_SYMBOL_GPL(udp_cmsg_send
);
961 int udp_sendmsg(struct sock
*sk
, struct msghdr
*msg
, size_t len
)
963 struct inet_sock
*inet
= inet_sk(sk
);
964 struct udp_sock
*up
= udp_sk(sk
);
965 DECLARE_SOCKADDR(struct sockaddr_in
*, usin
, msg
->msg_name
);
966 struct flowi4 fl4_stack
;
969 struct ipcm_cookie ipc
;
970 struct rtable
*rt
= NULL
;
973 __be32 daddr
, faddr
, saddr
;
976 int err
, is_udplite
= IS_UDPLITE(sk
);
977 int corkreq
= up
->corkflag
|| msg
->msg_flags
&MSG_MORE
;
978 int (*getfrag
)(void *, char *, int, int, int, struct sk_buff
*);
980 struct ip_options_data opt_copy
;
989 if (msg
->msg_flags
& MSG_OOB
) /* Mirror BSD error message compatibility */
992 getfrag
= is_udplite
? udplite_getfrag
: ip_generic_getfrag
;
994 fl4
= &inet
->cork
.fl
.u
.ip4
;
997 * There are pending frames.
998 * The socket lock must be held while it's corked.
1001 if (likely(up
->pending
)) {
1002 if (unlikely(up
->pending
!= AF_INET
)) {
1006 goto do_append_data
;
1010 ulen
+= sizeof(struct udphdr
);
1013 * Get and verify the address.
1016 if (msg
->msg_namelen
< sizeof(*usin
))
1018 if (usin
->sin_family
!= AF_INET
) {
1019 if (usin
->sin_family
!= AF_UNSPEC
)
1020 return -EAFNOSUPPORT
;
1023 daddr
= usin
->sin_addr
.s_addr
;
1024 dport
= usin
->sin_port
;
1028 if (sk
->sk_state
!= TCP_ESTABLISHED
)
1029 return -EDESTADDRREQ
;
1030 daddr
= inet
->inet_daddr
;
1031 dport
= inet
->inet_dport
;
1032 /* Open fast path for connected socket.
1033 Route will not be used, if at least one option is set.
1038 ipcm_init_sk(&ipc
, inet
);
1039 ipc
.gso_size
= up
->gso_size
;
1041 if (msg
->msg_controllen
) {
1042 err
= udp_cmsg_send(sk
, msg
, &ipc
.gso_size
);
1044 err
= ip_cmsg_send(sk
, msg
, &ipc
,
1045 sk
->sk_family
== AF_INET6
);
1046 if (unlikely(err
< 0)) {
1055 struct ip_options_rcu
*inet_opt
;
1058 inet_opt
= rcu_dereference(inet
->inet_opt
);
1060 memcpy(&opt_copy
, inet_opt
,
1061 sizeof(*inet_opt
) + inet_opt
->opt
.optlen
);
1062 ipc
.opt
= &opt_copy
.opt
;
1067 if (cgroup_bpf_enabled
&& !connected
) {
1068 err
= BPF_CGROUP_RUN_PROG_UDP4_SENDMSG_LOCK(sk
,
1069 (struct sockaddr
*)usin
, &ipc
.addr
);
1073 if (usin
->sin_port
== 0) {
1074 /* BPF program set invalid port. Reject it. */
1078 daddr
= usin
->sin_addr
.s_addr
;
1079 dport
= usin
->sin_port
;
1084 ipc
.addr
= faddr
= daddr
;
1086 if (ipc
.opt
&& ipc
.opt
->opt
.srr
) {
1091 faddr
= ipc
.opt
->opt
.faddr
;
1094 tos
= get_rttos(&ipc
, inet
);
1095 if (sock_flag(sk
, SOCK_LOCALROUTE
) ||
1096 (msg
->msg_flags
& MSG_DONTROUTE
) ||
1097 (ipc
.opt
&& ipc
.opt
->opt
.is_strictroute
)) {
1102 if (ipv4_is_multicast(daddr
)) {
1103 if (!ipc
.oif
|| netif_index_is_l3_master(sock_net(sk
), ipc
.oif
))
1104 ipc
.oif
= inet
->mc_index
;
1106 saddr
= inet
->mc_addr
;
1108 } else if (!ipc
.oif
) {
1109 ipc
.oif
= inet
->uc_index
;
1110 } else if (ipv4_is_lbcast(daddr
) && inet
->uc_index
) {
1111 /* oif is set, packet is to local broadcast and
1112 * and uc_index is set. oif is most likely set
1113 * by sk_bound_dev_if. If uc_index != oif check if the
1114 * oif is an L3 master and uc_index is an L3 slave.
1115 * If so, we want to allow the send using the uc_index.
1117 if (ipc
.oif
!= inet
->uc_index
&&
1118 ipc
.oif
== l3mdev_master_ifindex_by_index(sock_net(sk
),
1120 ipc
.oif
= inet
->uc_index
;
1125 rt
= (struct rtable
*)sk_dst_check(sk
, 0);
1128 struct net
*net
= sock_net(sk
);
1129 __u8 flow_flags
= inet_sk_flowi_flags(sk
);
1133 flowi4_init_output(fl4
, ipc
.oif
, sk
->sk_mark
, tos
,
1134 RT_SCOPE_UNIVERSE
, sk
->sk_protocol
,
1136 faddr
, saddr
, dport
, inet
->inet_sport
,
1139 security_sk_classify_flow(sk
, flowi4_to_flowi(fl4
));
1140 rt
= ip_route_output_flow(net
, fl4
, sk
);
1144 if (err
== -ENETUNREACH
)
1145 IP_INC_STATS(net
, IPSTATS_MIB_OUTNOROUTES
);
1150 if ((rt
->rt_flags
& RTCF_BROADCAST
) &&
1151 !sock_flag(sk
, SOCK_BROADCAST
))
1154 sk_dst_set(sk
, dst_clone(&rt
->dst
));
1157 if (msg
->msg_flags
&MSG_CONFIRM
)
1163 daddr
= ipc
.addr
= fl4
->daddr
;
1165 /* Lockless fast path for the non-corking case. */
1167 struct inet_cork cork
;
1169 skb
= ip_make_skb(sk
, fl4
, getfrag
, msg
, ulen
,
1170 sizeof(struct udphdr
), &ipc
, &rt
,
1171 &cork
, msg
->msg_flags
);
1173 if (!IS_ERR_OR_NULL(skb
))
1174 err
= udp_send_skb(skb
, fl4
, &cork
);
1179 if (unlikely(up
->pending
)) {
1180 /* The socket is already corked while preparing it. */
1181 /* ... which is an evident application bug. --ANK */
1184 net_dbg_ratelimited("socket already corked\n");
1189 * Now cork the socket to pend data.
1191 fl4
= &inet
->cork
.fl
.u
.ip4
;
1194 fl4
->fl4_dport
= dport
;
1195 fl4
->fl4_sport
= inet
->inet_sport
;
1196 up
->pending
= AF_INET
;
1200 err
= ip_append_data(sk
, fl4
, getfrag
, msg
, ulen
,
1201 sizeof(struct udphdr
), &ipc
, &rt
,
1202 corkreq
? msg
->msg_flags
|MSG_MORE
: msg
->msg_flags
);
1204 udp_flush_pending_frames(sk
);
1206 err
= udp_push_pending_frames(sk
);
1207 else if (unlikely(skb_queue_empty(&sk
->sk_write_queue
)))
1219 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting
1220 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1221 * we don't have a good statistic (IpOutDiscards but it can be too many
1222 * things). We could add another new stat but at least for now that
1223 * seems like overkill.
1225 if (err
== -ENOBUFS
|| test_bit(SOCK_NOSPACE
, &sk
->sk_socket
->flags
)) {
1226 UDP_INC_STATS(sock_net(sk
),
1227 UDP_MIB_SNDBUFERRORS
, is_udplite
);
1232 if (msg
->msg_flags
& MSG_PROBE
)
1233 dst_confirm_neigh(&rt
->dst
, &fl4
->daddr
);
1234 if (!(msg
->msg_flags
&MSG_PROBE
) || len
)
1235 goto back_from_confirm
;
1239 EXPORT_SYMBOL(udp_sendmsg
);
1241 int udp_sendpage(struct sock
*sk
, struct page
*page
, int offset
,
1242 size_t size
, int flags
)
1244 struct inet_sock
*inet
= inet_sk(sk
);
1245 struct udp_sock
*up
= udp_sk(sk
);
1248 if (flags
& MSG_SENDPAGE_NOTLAST
)
1252 struct msghdr msg
= { .msg_flags
= flags
|MSG_MORE
};
1254 /* Call udp_sendmsg to specify destination address which
1255 * sendpage interface can't pass.
1256 * This will succeed only when the socket is connected.
1258 ret
= udp_sendmsg(sk
, &msg
, 0);
1265 if (unlikely(!up
->pending
)) {
1268 net_dbg_ratelimited("cork failed\n");
1272 ret
= ip_append_page(sk
, &inet
->cork
.fl
.u
.ip4
,
1273 page
, offset
, size
, flags
);
1274 if (ret
== -EOPNOTSUPP
) {
1276 return sock_no_sendpage(sk
->sk_socket
, page
, offset
,
1280 udp_flush_pending_frames(sk
);
1285 if (!(up
->corkflag
|| (flags
&MSG_MORE
)))
1286 ret
= udp_push_pending_frames(sk
);
1294 #define UDP_SKB_IS_STATELESS 0x80000000
1296 static void udp_set_dev_scratch(struct sk_buff
*skb
)
1298 struct udp_dev_scratch
*scratch
= udp_skb_scratch(skb
);
1300 BUILD_BUG_ON(sizeof(struct udp_dev_scratch
) > sizeof(long));
1301 scratch
->_tsize_state
= skb
->truesize
;
1302 #if BITS_PER_LONG == 64
1303 scratch
->len
= skb
->len
;
1304 scratch
->csum_unnecessary
= !!skb_csum_unnecessary(skb
);
1305 scratch
->is_linear
= !skb_is_nonlinear(skb
);
1307 /* all head states execept sp (dst, sk, nf) are always cleared by
1308 * udp_rcv() and we need to preserve secpath, if present, to eventually
1309 * process IP_CMSG_PASSSEC at recvmsg() time
1311 if (likely(!skb_sec_path(skb
)))
1312 scratch
->_tsize_state
|= UDP_SKB_IS_STATELESS
;
1315 static int udp_skb_truesize(struct sk_buff
*skb
)
1317 return udp_skb_scratch(skb
)->_tsize_state
& ~UDP_SKB_IS_STATELESS
;
1320 static bool udp_skb_has_head_state(struct sk_buff
*skb
)
1322 return !(udp_skb_scratch(skb
)->_tsize_state
& UDP_SKB_IS_STATELESS
);
1325 /* fully reclaim rmem/fwd memory allocated for skb */
1326 static void udp_rmem_release(struct sock
*sk
, int size
, int partial
,
1327 bool rx_queue_lock_held
)
1329 struct udp_sock
*up
= udp_sk(sk
);
1330 struct sk_buff_head
*sk_queue
;
1333 if (likely(partial
)) {
1334 up
->forward_deficit
+= size
;
1335 size
= up
->forward_deficit
;
1336 if (size
< (sk
->sk_rcvbuf
>> 2))
1339 size
+= up
->forward_deficit
;
1341 up
->forward_deficit
= 0;
1343 /* acquire the sk_receive_queue for fwd allocated memory scheduling,
1344 * if the called don't held it already
1346 sk_queue
= &sk
->sk_receive_queue
;
1347 if (!rx_queue_lock_held
)
1348 spin_lock(&sk_queue
->lock
);
1351 sk
->sk_forward_alloc
+= size
;
1352 amt
= (sk
->sk_forward_alloc
- partial
) & ~(SK_MEM_QUANTUM
- 1);
1353 sk
->sk_forward_alloc
-= amt
;
1356 __sk_mem_reduce_allocated(sk
, amt
>> SK_MEM_QUANTUM_SHIFT
);
1358 atomic_sub(size
, &sk
->sk_rmem_alloc
);
1360 /* this can save us from acquiring the rx queue lock on next receive */
1361 skb_queue_splice_tail_init(sk_queue
, &up
->reader_queue
);
1363 if (!rx_queue_lock_held
)
1364 spin_unlock(&sk_queue
->lock
);
1367 /* Note: called with reader_queue.lock held.
1368 * Instead of using skb->truesize here, find a copy of it in skb->dev_scratch
1369 * This avoids a cache line miss while receive_queue lock is held.
1370 * Look at __udp_enqueue_schedule_skb() to find where this copy is done.
1372 void udp_skb_destructor(struct sock
*sk
, struct sk_buff
*skb
)
1374 prefetch(&skb
->data
);
1375 udp_rmem_release(sk
, udp_skb_truesize(skb
), 1, false);
1377 EXPORT_SYMBOL(udp_skb_destructor
);
1379 /* as above, but the caller held the rx queue lock, too */
1380 static void udp_skb_dtor_locked(struct sock
*sk
, struct sk_buff
*skb
)
1382 prefetch(&skb
->data
);
1383 udp_rmem_release(sk
, udp_skb_truesize(skb
), 1, true);
1386 /* Idea of busylocks is to let producers grab an extra spinlock
1387 * to relieve pressure on the receive_queue spinlock shared by consumer.
1388 * Under flood, this means that only one producer can be in line
1389 * trying to acquire the receive_queue spinlock.
1390 * These busylock can be allocated on a per cpu manner, instead of a
1391 * per socket one (that would consume a cache line per socket)
1393 static int udp_busylocks_log __read_mostly
;
1394 static spinlock_t
*udp_busylocks __read_mostly
;
1396 static spinlock_t
*busylock_acquire(void *ptr
)
1400 busy
= udp_busylocks
+ hash_ptr(ptr
, udp_busylocks_log
);
1405 static void busylock_release(spinlock_t
*busy
)
1411 int __udp_enqueue_schedule_skb(struct sock
*sk
, struct sk_buff
*skb
)
1413 struct sk_buff_head
*list
= &sk
->sk_receive_queue
;
1414 int rmem
, delta
, amt
, err
= -ENOMEM
;
1415 spinlock_t
*busy
= NULL
;
1418 /* try to avoid the costly atomic add/sub pair when the receive
1419 * queue is full; always allow at least a packet
1421 rmem
= atomic_read(&sk
->sk_rmem_alloc
);
1422 if (rmem
> sk
->sk_rcvbuf
)
1425 /* Under mem pressure, it might be helpful to help udp_recvmsg()
1426 * having linear skbs :
1427 * - Reduce memory overhead and thus increase receive queue capacity
1428 * - Less cache line misses at copyout() time
1429 * - Less work at consume_skb() (less alien page frag freeing)
1431 if (rmem
> (sk
->sk_rcvbuf
>> 1)) {
1434 busy
= busylock_acquire(sk
);
1436 size
= skb
->truesize
;
1437 udp_set_dev_scratch(skb
);
1439 /* we drop only if the receive buf is full and the receive
1440 * queue contains some other skb
1442 rmem
= atomic_add_return(size
, &sk
->sk_rmem_alloc
);
1443 if (rmem
> (size
+ sk
->sk_rcvbuf
))
1446 spin_lock(&list
->lock
);
1447 if (size
>= sk
->sk_forward_alloc
) {
1448 amt
= sk_mem_pages(size
);
1449 delta
= amt
<< SK_MEM_QUANTUM_SHIFT
;
1450 if (!__sk_mem_raise_allocated(sk
, delta
, amt
, SK_MEM_RECV
)) {
1452 spin_unlock(&list
->lock
);
1456 sk
->sk_forward_alloc
+= delta
;
1459 sk
->sk_forward_alloc
-= size
;
1461 /* no need to setup a destructor, we will explicitly release the
1462 * forward allocated memory on dequeue
1464 sock_skb_set_dropcount(sk
, skb
);
1466 __skb_queue_tail(list
, skb
);
1467 spin_unlock(&list
->lock
);
1469 if (!sock_flag(sk
, SOCK_DEAD
))
1470 sk
->sk_data_ready(sk
);
1472 busylock_release(busy
);
1476 atomic_sub(skb
->truesize
, &sk
->sk_rmem_alloc
);
1479 atomic_inc(&sk
->sk_drops
);
1480 busylock_release(busy
);
1483 EXPORT_SYMBOL_GPL(__udp_enqueue_schedule_skb
);
1485 void udp_destruct_sock(struct sock
*sk
)
1487 /* reclaim completely the forward allocated memory */
1488 struct udp_sock
*up
= udp_sk(sk
);
1489 unsigned int total
= 0;
1490 struct sk_buff
*skb
;
1492 skb_queue_splice_tail_init(&sk
->sk_receive_queue
, &up
->reader_queue
);
1493 while ((skb
= __skb_dequeue(&up
->reader_queue
)) != NULL
) {
1494 total
+= skb
->truesize
;
1497 udp_rmem_release(sk
, total
, 0, true);
1499 inet_sock_destruct(sk
);
1501 EXPORT_SYMBOL_GPL(udp_destruct_sock
);
1503 int udp_init_sock(struct sock
*sk
)
1505 skb_queue_head_init(&udp_sk(sk
)->reader_queue
);
1506 sk
->sk_destruct
= udp_destruct_sock
;
1509 EXPORT_SYMBOL_GPL(udp_init_sock
);
1511 void skb_consume_udp(struct sock
*sk
, struct sk_buff
*skb
, int len
)
1513 if (unlikely(READ_ONCE(sk
->sk_peek_off
) >= 0)) {
1514 bool slow
= lock_sock_fast(sk
);
1516 sk_peek_offset_bwd(sk
, len
);
1517 unlock_sock_fast(sk
, slow
);
1520 if (!skb_unref(skb
))
1523 /* In the more common cases we cleared the head states previously,
1524 * see __udp_queue_rcv_skb().
1526 if (unlikely(udp_skb_has_head_state(skb
)))
1527 skb_release_head_state(skb
);
1528 __consume_stateless_skb(skb
);
1530 EXPORT_SYMBOL_GPL(skb_consume_udp
);
1532 static struct sk_buff
*__first_packet_length(struct sock
*sk
,
1533 struct sk_buff_head
*rcvq
,
1536 struct sk_buff
*skb
;
1538 while ((skb
= skb_peek(rcvq
)) != NULL
) {
1539 if (udp_lib_checksum_complete(skb
)) {
1540 __UDP_INC_STATS(sock_net(sk
), UDP_MIB_CSUMERRORS
,
1542 __UDP_INC_STATS(sock_net(sk
), UDP_MIB_INERRORS
,
1544 atomic_inc(&sk
->sk_drops
);
1545 __skb_unlink(skb
, rcvq
);
1546 *total
+= skb
->truesize
;
1549 /* the csum related bits could be changed, refresh
1552 udp_set_dev_scratch(skb
);
1560 * first_packet_length - return length of first packet in receive queue
1563 * Drops all bad checksum frames, until a valid one is found.
1564 * Returns the length of found skb, or -1 if none is found.
1566 static int first_packet_length(struct sock
*sk
)
1568 struct sk_buff_head
*rcvq
= &udp_sk(sk
)->reader_queue
;
1569 struct sk_buff_head
*sk_queue
= &sk
->sk_receive_queue
;
1570 struct sk_buff
*skb
;
1574 spin_lock_bh(&rcvq
->lock
);
1575 skb
= __first_packet_length(sk
, rcvq
, &total
);
1576 if (!skb
&& !skb_queue_empty(sk_queue
)) {
1577 spin_lock(&sk_queue
->lock
);
1578 skb_queue_splice_tail_init(sk_queue
, rcvq
);
1579 spin_unlock(&sk_queue
->lock
);
1581 skb
= __first_packet_length(sk
, rcvq
, &total
);
1583 res
= skb
? skb
->len
: -1;
1585 udp_rmem_release(sk
, total
, 1, false);
1586 spin_unlock_bh(&rcvq
->lock
);
1591 * IOCTL requests applicable to the UDP protocol
1594 int udp_ioctl(struct sock
*sk
, int cmd
, unsigned long arg
)
1599 int amount
= sk_wmem_alloc_get(sk
);
1601 return put_user(amount
, (int __user
*)arg
);
1606 int amount
= max_t(int, 0, first_packet_length(sk
));
1608 return put_user(amount
, (int __user
*)arg
);
1612 return -ENOIOCTLCMD
;
1617 EXPORT_SYMBOL(udp_ioctl
);
1619 struct sk_buff
*__skb_recv_udp(struct sock
*sk
, unsigned int flags
,
1620 int noblock
, int *off
, int *err
)
1622 struct sk_buff_head
*sk_queue
= &sk
->sk_receive_queue
;
1623 struct sk_buff_head
*queue
;
1624 struct sk_buff
*last
;
1628 queue
= &udp_sk(sk
)->reader_queue
;
1629 flags
|= noblock
? MSG_DONTWAIT
: 0;
1630 timeo
= sock_rcvtimeo(sk
, flags
& MSG_DONTWAIT
);
1632 struct sk_buff
*skb
;
1634 error
= sock_error(sk
);
1640 spin_lock_bh(&queue
->lock
);
1641 skb
= __skb_try_recv_from_queue(sk
, queue
, flags
,
1645 spin_unlock_bh(&queue
->lock
);
1649 if (skb_queue_empty(sk_queue
)) {
1650 spin_unlock_bh(&queue
->lock
);
1654 /* refill the reader queue and walk it again
1655 * keep both queues locked to avoid re-acquiring
1656 * the sk_receive_queue lock if fwd memory scheduling
1659 spin_lock(&sk_queue
->lock
);
1660 skb_queue_splice_tail_init(sk_queue
, queue
);
1662 skb
= __skb_try_recv_from_queue(sk
, queue
, flags
,
1663 udp_skb_dtor_locked
,
1665 spin_unlock(&sk_queue
->lock
);
1666 spin_unlock_bh(&queue
->lock
);
1671 if (!sk_can_busy_loop(sk
))
1674 sk_busy_loop(sk
, flags
& MSG_DONTWAIT
);
1675 } while (!skb_queue_empty(sk_queue
));
1677 /* sk_queue is empty, reader_queue may contain peeked packets */
1679 !__skb_wait_for_more_packets(sk
, &error
, &timeo
,
1680 (struct sk_buff
*)sk_queue
));
1685 EXPORT_SYMBOL(__skb_recv_udp
);
1688 * This should be easy, if there is something there we
1689 * return it, otherwise we block.
1692 int udp_recvmsg(struct sock
*sk
, struct msghdr
*msg
, size_t len
, int noblock
,
1693 int flags
, int *addr_len
)
1695 struct inet_sock
*inet
= inet_sk(sk
);
1696 DECLARE_SOCKADDR(struct sockaddr_in
*, sin
, msg
->msg_name
);
1697 struct sk_buff
*skb
;
1698 unsigned int ulen
, copied
;
1699 int off
, err
, peeking
= flags
& MSG_PEEK
;
1700 int is_udplite
= IS_UDPLITE(sk
);
1701 bool checksum_valid
= false;
1703 if (flags
& MSG_ERRQUEUE
)
1704 return ip_recv_error(sk
, msg
, len
, addr_len
);
1707 off
= sk_peek_offset(sk
, flags
);
1708 skb
= __skb_recv_udp(sk
, flags
, noblock
, &off
, &err
);
1712 ulen
= udp_skb_len(skb
);
1714 if (copied
> ulen
- off
)
1715 copied
= ulen
- off
;
1716 else if (copied
< ulen
)
1717 msg
->msg_flags
|= MSG_TRUNC
;
1720 * If checksum is needed at all, try to do it while copying the
1721 * data. If the data is truncated, or if we only want a partial
1722 * coverage checksum (UDP-Lite), do it before the copy.
1725 if (copied
< ulen
|| peeking
||
1726 (is_udplite
&& UDP_SKB_CB(skb
)->partial_cov
)) {
1727 checksum_valid
= udp_skb_csum_unnecessary(skb
) ||
1728 !__udp_lib_checksum_complete(skb
);
1729 if (!checksum_valid
)
1733 if (checksum_valid
|| udp_skb_csum_unnecessary(skb
)) {
1734 if (udp_skb_is_linear(skb
))
1735 err
= copy_linear_skb(skb
, copied
, off
, &msg
->msg_iter
);
1737 err
= skb_copy_datagram_msg(skb
, off
, msg
, copied
);
1739 err
= skb_copy_and_csum_datagram_msg(skb
, off
, msg
);
1745 if (unlikely(err
)) {
1747 atomic_inc(&sk
->sk_drops
);
1748 UDP_INC_STATS(sock_net(sk
),
1749 UDP_MIB_INERRORS
, is_udplite
);
1756 UDP_INC_STATS(sock_net(sk
),
1757 UDP_MIB_INDATAGRAMS
, is_udplite
);
1759 sock_recv_ts_and_drops(msg
, sk
, skb
);
1761 /* Copy the address. */
1763 sin
->sin_family
= AF_INET
;
1764 sin
->sin_port
= udp_hdr(skb
)->source
;
1765 sin
->sin_addr
.s_addr
= ip_hdr(skb
)->saddr
;
1766 memset(sin
->sin_zero
, 0, sizeof(sin
->sin_zero
));
1767 *addr_len
= sizeof(*sin
);
1769 if (cgroup_bpf_enabled
)
1770 BPF_CGROUP_RUN_PROG_UDP4_RECVMSG_LOCK(sk
,
1771 (struct sockaddr
*)sin
);
1774 if (udp_sk(sk
)->gro_enabled
)
1775 udp_cmsg_recv(msg
, sk
, skb
);
1777 if (inet
->cmsg_flags
)
1778 ip_cmsg_recv_offset(msg
, sk
, skb
, sizeof(struct udphdr
), off
);
1781 if (flags
& MSG_TRUNC
)
1784 skb_consume_udp(sk
, skb
, peeking
? -err
: err
);
1788 if (!__sk_queue_drop_skb(sk
, &udp_sk(sk
)->reader_queue
, skb
, flags
,
1789 udp_skb_destructor
)) {
1790 UDP_INC_STATS(sock_net(sk
), UDP_MIB_CSUMERRORS
, is_udplite
);
1791 UDP_INC_STATS(sock_net(sk
), UDP_MIB_INERRORS
, is_udplite
);
1795 /* starting over for a new packet, but check if we need to yield */
1797 msg
->msg_flags
&= ~MSG_TRUNC
;
1801 int udp_pre_connect(struct sock
*sk
, struct sockaddr
*uaddr
, int addr_len
)
1803 /* This check is replicated from __ip4_datagram_connect() and
1804 * intended to prevent BPF program called below from accessing bytes
1805 * that are out of the bound specified by user in addr_len.
1807 if (addr_len
< sizeof(struct sockaddr_in
))
1810 return BPF_CGROUP_RUN_PROG_INET4_CONNECT_LOCK(sk
, uaddr
);
1812 EXPORT_SYMBOL(udp_pre_connect
);
1814 int __udp_disconnect(struct sock
*sk
, int flags
)
1816 struct inet_sock
*inet
= inet_sk(sk
);
1818 * 1003.1g - break association.
1821 sk
->sk_state
= TCP_CLOSE
;
1822 inet
->inet_daddr
= 0;
1823 inet
->inet_dport
= 0;
1824 sock_rps_reset_rxhash(sk
);
1825 sk
->sk_bound_dev_if
= 0;
1826 if (!(sk
->sk_userlocks
& SOCK_BINDADDR_LOCK
))
1827 inet_reset_saddr(sk
);
1829 if (!(sk
->sk_userlocks
& SOCK_BINDPORT_LOCK
)) {
1830 sk
->sk_prot
->unhash(sk
);
1831 inet
->inet_sport
= 0;
1836 EXPORT_SYMBOL(__udp_disconnect
);
1838 int udp_disconnect(struct sock
*sk
, int flags
)
1841 __udp_disconnect(sk
, flags
);
1845 EXPORT_SYMBOL(udp_disconnect
);
1847 void udp_lib_unhash(struct sock
*sk
)
1849 if (sk_hashed(sk
)) {
1850 struct udp_table
*udptable
= sk
->sk_prot
->h
.udp_table
;
1851 struct udp_hslot
*hslot
, *hslot2
;
1853 hslot
= udp_hashslot(udptable
, sock_net(sk
),
1854 udp_sk(sk
)->udp_port_hash
);
1855 hslot2
= udp_hashslot2(udptable
, udp_sk(sk
)->udp_portaddr_hash
);
1857 spin_lock_bh(&hslot
->lock
);
1858 if (rcu_access_pointer(sk
->sk_reuseport_cb
))
1859 reuseport_detach_sock(sk
);
1860 if (sk_del_node_init_rcu(sk
)) {
1862 inet_sk(sk
)->inet_num
= 0;
1863 sock_prot_inuse_add(sock_net(sk
), sk
->sk_prot
, -1);
1865 spin_lock(&hslot2
->lock
);
1866 hlist_del_init_rcu(&udp_sk(sk
)->udp_portaddr_node
);
1868 spin_unlock(&hslot2
->lock
);
1870 spin_unlock_bh(&hslot
->lock
);
1873 EXPORT_SYMBOL(udp_lib_unhash
);
1876 * inet_rcv_saddr was changed, we must rehash secondary hash
1878 void udp_lib_rehash(struct sock
*sk
, u16 newhash
)
1880 if (sk_hashed(sk
)) {
1881 struct udp_table
*udptable
= sk
->sk_prot
->h
.udp_table
;
1882 struct udp_hslot
*hslot
, *hslot2
, *nhslot2
;
1884 hslot2
= udp_hashslot2(udptable
, udp_sk(sk
)->udp_portaddr_hash
);
1885 nhslot2
= udp_hashslot2(udptable
, newhash
);
1886 udp_sk(sk
)->udp_portaddr_hash
= newhash
;
1888 if (hslot2
!= nhslot2
||
1889 rcu_access_pointer(sk
->sk_reuseport_cb
)) {
1890 hslot
= udp_hashslot(udptable
, sock_net(sk
),
1891 udp_sk(sk
)->udp_port_hash
);
1892 /* we must lock primary chain too */
1893 spin_lock_bh(&hslot
->lock
);
1894 if (rcu_access_pointer(sk
->sk_reuseport_cb
))
1895 reuseport_detach_sock(sk
);
1897 if (hslot2
!= nhslot2
) {
1898 spin_lock(&hslot2
->lock
);
1899 hlist_del_init_rcu(&udp_sk(sk
)->udp_portaddr_node
);
1901 spin_unlock(&hslot2
->lock
);
1903 spin_lock(&nhslot2
->lock
);
1904 hlist_add_head_rcu(&udp_sk(sk
)->udp_portaddr_node
,
1907 spin_unlock(&nhslot2
->lock
);
1910 spin_unlock_bh(&hslot
->lock
);
1914 EXPORT_SYMBOL(udp_lib_rehash
);
1916 void udp_v4_rehash(struct sock
*sk
)
1918 u16 new_hash
= ipv4_portaddr_hash(sock_net(sk
),
1919 inet_sk(sk
)->inet_rcv_saddr
,
1920 inet_sk(sk
)->inet_num
);
1921 udp_lib_rehash(sk
, new_hash
);
1924 static int __udp_queue_rcv_skb(struct sock
*sk
, struct sk_buff
*skb
)
1928 if (inet_sk(sk
)->inet_daddr
) {
1929 sock_rps_save_rxhash(sk
, skb
);
1930 sk_mark_napi_id(sk
, skb
);
1931 sk_incoming_cpu_update(sk
);
1933 sk_mark_napi_id_once(sk
, skb
);
1936 rc
= __udp_enqueue_schedule_skb(sk
, skb
);
1938 int is_udplite
= IS_UDPLITE(sk
);
1940 /* Note that an ENOMEM error is charged twice */
1942 UDP_INC_STATS(sock_net(sk
), UDP_MIB_RCVBUFERRORS
,
1944 UDP_INC_STATS(sock_net(sk
), UDP_MIB_INERRORS
, is_udplite
);
1946 trace_udp_fail_queue_rcv_skb(rc
, sk
);
1956 * >0: "udp encap" protocol resubmission
1958 * Note that in the success and error cases, the skb is assumed to
1959 * have either been requeued or freed.
1961 static int udp_queue_rcv_one_skb(struct sock
*sk
, struct sk_buff
*skb
)
1963 struct udp_sock
*up
= udp_sk(sk
);
1964 int is_udplite
= IS_UDPLITE(sk
);
1967 * Charge it to the socket, dropping if the queue is full.
1969 if (!xfrm4_policy_check(sk
, XFRM_POLICY_IN
, skb
))
1973 if (static_branch_unlikely(&udp_encap_needed_key
) && up
->encap_type
) {
1974 int (*encap_rcv
)(struct sock
*sk
, struct sk_buff
*skb
);
1977 * This is an encapsulation socket so pass the skb to
1978 * the socket's udp_encap_rcv() hook. Otherwise, just
1979 * fall through and pass this up the UDP socket.
1980 * up->encap_rcv() returns the following value:
1981 * =0 if skb was successfully passed to the encap
1982 * handler or was discarded by it.
1983 * >0 if skb should be passed on to UDP.
1984 * <0 if skb should be resubmitted as proto -N
1987 /* if we're overly short, let UDP handle it */
1988 encap_rcv
= READ_ONCE(up
->encap_rcv
);
1992 /* Verify checksum before giving to encap */
1993 if (udp_lib_checksum_complete(skb
))
1996 ret
= encap_rcv(sk
, skb
);
1998 __UDP_INC_STATS(sock_net(sk
),
1999 UDP_MIB_INDATAGRAMS
,
2005 /* FALLTHROUGH -- it's a UDP Packet */
2009 * UDP-Lite specific tests, ignored on UDP sockets
2011 if ((is_udplite
& UDPLITE_RECV_CC
) && UDP_SKB_CB(skb
)->partial_cov
) {
2014 * MIB statistics other than incrementing the error count are
2015 * disabled for the following two types of errors: these depend
2016 * on the application settings, not on the functioning of the
2017 * protocol stack as such.
2019 * RFC 3828 here recommends (sec 3.3): "There should also be a
2020 * way ... to ... at least let the receiving application block
2021 * delivery of packets with coverage values less than a value
2022 * provided by the application."
2024 if (up
->pcrlen
== 0) { /* full coverage was set */
2025 net_dbg_ratelimited("UDPLite: partial coverage %d while full coverage %d requested\n",
2026 UDP_SKB_CB(skb
)->cscov
, skb
->len
);
2029 /* The next case involves violating the min. coverage requested
2030 * by the receiver. This is subtle: if receiver wants x and x is
2031 * greater than the buffersize/MTU then receiver will complain
2032 * that it wants x while sender emits packets of smaller size y.
2033 * Therefore the above ...()->partial_cov statement is essential.
2035 if (UDP_SKB_CB(skb
)->cscov
< up
->pcrlen
) {
2036 net_dbg_ratelimited("UDPLite: coverage %d too small, need min %d\n",
2037 UDP_SKB_CB(skb
)->cscov
, up
->pcrlen
);
2042 prefetch(&sk
->sk_rmem_alloc
);
2043 if (rcu_access_pointer(sk
->sk_filter
) &&
2044 udp_lib_checksum_complete(skb
))
2047 if (sk_filter_trim_cap(sk
, skb
, sizeof(struct udphdr
)))
2050 udp_csum_pull_header(skb
);
2052 ipv4_pktinfo_prepare(sk
, skb
);
2053 return __udp_queue_rcv_skb(sk
, skb
);
2056 __UDP_INC_STATS(sock_net(sk
), UDP_MIB_CSUMERRORS
, is_udplite
);
2058 __UDP_INC_STATS(sock_net(sk
), UDP_MIB_INERRORS
, is_udplite
);
2059 atomic_inc(&sk
->sk_drops
);
2064 static int udp_queue_rcv_skb(struct sock
*sk
, struct sk_buff
*skb
)
2066 struct sk_buff
*next
, *segs
;
2069 if (likely(!udp_unexpected_gso(sk
, skb
)))
2070 return udp_queue_rcv_one_skb(sk
, skb
);
2072 BUILD_BUG_ON(sizeof(struct udp_skb_cb
) > SKB_SGO_CB_OFFSET
);
2073 __skb_push(skb
, -skb_mac_offset(skb
));
2074 segs
= udp_rcv_segment(sk
, skb
, true);
2075 for (skb
= segs
; skb
; skb
= next
) {
2077 __skb_pull(skb
, skb_transport_offset(skb
));
2078 ret
= udp_queue_rcv_one_skb(sk
, skb
);
2080 ip_protocol_deliver_rcu(dev_net(skb
->dev
), skb
, -ret
);
2085 /* For TCP sockets, sk_rx_dst is protected by socket lock
2086 * For UDP, we use xchg() to guard against concurrent changes.
2088 bool udp_sk_rx_dst_set(struct sock
*sk
, struct dst_entry
*dst
)
2090 struct dst_entry
*old
;
2092 if (dst_hold_safe(dst
)) {
2093 old
= xchg(&sk
->sk_rx_dst
, dst
);
2099 EXPORT_SYMBOL(udp_sk_rx_dst_set
);
2102 * Multicasts and broadcasts go to each listener.
2104 * Note: called only from the BH handler context.
2106 static int __udp4_lib_mcast_deliver(struct net
*net
, struct sk_buff
*skb
,
2108 __be32 saddr
, __be32 daddr
,
2109 struct udp_table
*udptable
,
2112 struct sock
*sk
, *first
= NULL
;
2113 unsigned short hnum
= ntohs(uh
->dest
);
2114 struct udp_hslot
*hslot
= udp_hashslot(udptable
, net
, hnum
);
2115 unsigned int hash2
= 0, hash2_any
= 0, use_hash2
= (hslot
->count
> 10);
2116 unsigned int offset
= offsetof(typeof(*sk
), sk_node
);
2117 int dif
= skb
->dev
->ifindex
;
2118 int sdif
= inet_sdif(skb
);
2119 struct hlist_node
*node
;
2120 struct sk_buff
*nskb
;
2123 hash2_any
= ipv4_portaddr_hash(net
, htonl(INADDR_ANY
), hnum
) &
2125 hash2
= ipv4_portaddr_hash(net
, daddr
, hnum
) & udptable
->mask
;
2127 hslot
= &udptable
->hash2
[hash2
];
2128 offset
= offsetof(typeof(*sk
), __sk_common
.skc_portaddr_node
);
2131 sk_for_each_entry_offset_rcu(sk
, node
, &hslot
->head
, offset
) {
2132 if (!__udp_is_mcast_sock(net
, sk
, uh
->dest
, daddr
,
2133 uh
->source
, saddr
, dif
, sdif
, hnum
))
2140 nskb
= skb_clone(skb
, GFP_ATOMIC
);
2142 if (unlikely(!nskb
)) {
2143 atomic_inc(&sk
->sk_drops
);
2144 __UDP_INC_STATS(net
, UDP_MIB_RCVBUFERRORS
,
2146 __UDP_INC_STATS(net
, UDP_MIB_INERRORS
,
2150 if (udp_queue_rcv_skb(sk
, nskb
) > 0)
2154 /* Also lookup *:port if we are using hash2 and haven't done so yet. */
2155 if (use_hash2
&& hash2
!= hash2_any
) {
2161 if (udp_queue_rcv_skb(first
, skb
) > 0)
2165 __UDP_INC_STATS(net
, UDP_MIB_IGNOREDMULTI
,
2166 proto
== IPPROTO_UDPLITE
);
2171 /* Initialize UDP checksum. If exited with zero value (success),
2172 * CHECKSUM_UNNECESSARY means, that no more checks are required.
2173 * Otherwise, csum completion requires checksumming packet body,
2174 * including udp header and folding it to skb->csum.
2176 static inline int udp4_csum_init(struct sk_buff
*skb
, struct udphdr
*uh
,
2181 UDP_SKB_CB(skb
)->partial_cov
= 0;
2182 UDP_SKB_CB(skb
)->cscov
= skb
->len
;
2184 if (proto
== IPPROTO_UDPLITE
) {
2185 err
= udplite_checksum_init(skb
, uh
);
2189 if (UDP_SKB_CB(skb
)->partial_cov
) {
2190 skb
->csum
= inet_compute_pseudo(skb
, proto
);
2195 /* Note, we are only interested in != 0 or == 0, thus the
2198 err
= (__force
int)skb_checksum_init_zero_check(skb
, proto
, uh
->check
,
2199 inet_compute_pseudo
);
2203 if (skb
->ip_summed
== CHECKSUM_COMPLETE
&& !skb
->csum_valid
) {
2204 /* If SW calculated the value, we know it's bad */
2205 if (skb
->csum_complete_sw
)
2208 /* HW says the value is bad. Let's validate that.
2209 * skb->csum is no longer the full packet checksum,
2210 * so don't treat it as such.
2212 skb_checksum_complete_unset(skb
);
2218 /* wrapper for udp_queue_rcv_skb tacking care of csum conversion and
2219 * return code conversion for ip layer consumption
2221 static int udp_unicast_rcv_skb(struct sock
*sk
, struct sk_buff
*skb
,
2226 if (inet_get_convert_csum(sk
) && uh
->check
&& !IS_UDPLITE(sk
))
2227 skb_checksum_try_convert(skb
, IPPROTO_UDP
, inet_compute_pseudo
);
2229 ret
= udp_queue_rcv_skb(sk
, skb
);
2231 /* a return value > 0 means to resubmit the input, but
2232 * it wants the return to be -protocol, or 0
2240 * All we need to do is get the socket, and then do a checksum.
2243 int __udp4_lib_rcv(struct sk_buff
*skb
, struct udp_table
*udptable
,
2248 unsigned short ulen
;
2249 struct rtable
*rt
= skb_rtable(skb
);
2250 __be32 saddr
, daddr
;
2251 struct net
*net
= dev_net(skb
->dev
);
2254 * Validate the packet.
2256 if (!pskb_may_pull(skb
, sizeof(struct udphdr
)))
2257 goto drop
; /* No space for header. */
2260 ulen
= ntohs(uh
->len
);
2261 saddr
= ip_hdr(skb
)->saddr
;
2262 daddr
= ip_hdr(skb
)->daddr
;
2264 if (ulen
> skb
->len
)
2267 if (proto
== IPPROTO_UDP
) {
2268 /* UDP validates ulen. */
2269 if (ulen
< sizeof(*uh
) || pskb_trim_rcsum(skb
, ulen
))
2274 if (udp4_csum_init(skb
, uh
, proto
))
2277 sk
= skb_steal_sock(skb
);
2279 struct dst_entry
*dst
= skb_dst(skb
);
2282 if (unlikely(sk
->sk_rx_dst
!= dst
))
2283 udp_sk_rx_dst_set(sk
, dst
);
2285 ret
= udp_unicast_rcv_skb(sk
, skb
, uh
);
2290 if (rt
->rt_flags
& (RTCF_BROADCAST
|RTCF_MULTICAST
))
2291 return __udp4_lib_mcast_deliver(net
, skb
, uh
,
2292 saddr
, daddr
, udptable
, proto
);
2294 sk
= __udp4_lib_lookup_skb(skb
, uh
->source
, uh
->dest
, udptable
);
2296 return udp_unicast_rcv_skb(sk
, skb
, uh
);
2298 if (!xfrm4_policy_check(NULL
, XFRM_POLICY_IN
, skb
))
2302 /* No socket. Drop packet silently, if checksum is wrong */
2303 if (udp_lib_checksum_complete(skb
))
2306 __UDP_INC_STATS(net
, UDP_MIB_NOPORTS
, proto
== IPPROTO_UDPLITE
);
2307 icmp_send(skb
, ICMP_DEST_UNREACH
, ICMP_PORT_UNREACH
, 0);
2310 * Hmm. We got an UDP packet to a port to which we
2311 * don't wanna listen. Ignore it.
2317 net_dbg_ratelimited("UDP%s: short packet: From %pI4:%u %d/%d to %pI4:%u\n",
2318 proto
== IPPROTO_UDPLITE
? "Lite" : "",
2319 &saddr
, ntohs(uh
->source
),
2321 &daddr
, ntohs(uh
->dest
));
2326 * RFC1122: OK. Discards the bad packet silently (as far as
2327 * the network is concerned, anyway) as per 4.1.3.4 (MUST).
2329 net_dbg_ratelimited("UDP%s: bad checksum. From %pI4:%u to %pI4:%u ulen %d\n",
2330 proto
== IPPROTO_UDPLITE
? "Lite" : "",
2331 &saddr
, ntohs(uh
->source
), &daddr
, ntohs(uh
->dest
),
2333 __UDP_INC_STATS(net
, UDP_MIB_CSUMERRORS
, proto
== IPPROTO_UDPLITE
);
2335 __UDP_INC_STATS(net
, UDP_MIB_INERRORS
, proto
== IPPROTO_UDPLITE
);
2340 /* We can only early demux multicast if there is a single matching socket.
2341 * If more than one socket found returns NULL
2343 static struct sock
*__udp4_lib_mcast_demux_lookup(struct net
*net
,
2344 __be16 loc_port
, __be32 loc_addr
,
2345 __be16 rmt_port
, __be32 rmt_addr
,
2348 struct sock
*sk
, *result
;
2349 unsigned short hnum
= ntohs(loc_port
);
2350 unsigned int slot
= udp_hashfn(net
, hnum
, udp_table
.mask
);
2351 struct udp_hslot
*hslot
= &udp_table
.hash
[slot
];
2353 /* Do not bother scanning a too big list */
2354 if (hslot
->count
> 10)
2358 sk_for_each_rcu(sk
, &hslot
->head
) {
2359 if (__udp_is_mcast_sock(net
, sk
, loc_port
, loc_addr
,
2360 rmt_port
, rmt_addr
, dif
, sdif
, hnum
)) {
2370 /* For unicast we should only early demux connected sockets or we can
2371 * break forwarding setups. The chains here can be long so only check
2372 * if the first socket is an exact match and if not move on.
2374 static struct sock
*__udp4_lib_demux_lookup(struct net
*net
,
2375 __be16 loc_port
, __be32 loc_addr
,
2376 __be16 rmt_port
, __be32 rmt_addr
,
2379 unsigned short hnum
= ntohs(loc_port
);
2380 unsigned int hash2
= ipv4_portaddr_hash(net
, loc_addr
, hnum
);
2381 unsigned int slot2
= hash2
& udp_table
.mask
;
2382 struct udp_hslot
*hslot2
= &udp_table
.hash2
[slot2
];
2383 INET_ADDR_COOKIE(acookie
, rmt_addr
, loc_addr
);
2384 const __portpair ports
= INET_COMBINED_PORTS(rmt_port
, hnum
);
2387 udp_portaddr_for_each_entry_rcu(sk
, &hslot2
->head
) {
2388 if (INET_MATCH(sk
, net
, acookie
, rmt_addr
,
2389 loc_addr
, ports
, dif
, sdif
))
2391 /* Only check first socket in chain */
2397 int udp_v4_early_demux(struct sk_buff
*skb
)
2399 struct net
*net
= dev_net(skb
->dev
);
2400 struct in_device
*in_dev
= NULL
;
2401 const struct iphdr
*iph
;
2402 const struct udphdr
*uh
;
2403 struct sock
*sk
= NULL
;
2404 struct dst_entry
*dst
;
2405 int dif
= skb
->dev
->ifindex
;
2406 int sdif
= inet_sdif(skb
);
2409 /* validate the packet */
2410 if (!pskb_may_pull(skb
, skb_transport_offset(skb
) + sizeof(struct udphdr
)))
2416 if (skb
->pkt_type
== PACKET_MULTICAST
) {
2417 in_dev
= __in_dev_get_rcu(skb
->dev
);
2422 ours
= ip_check_mc_rcu(in_dev
, iph
->daddr
, iph
->saddr
,
2427 sk
= __udp4_lib_mcast_demux_lookup(net
, uh
->dest
, iph
->daddr
,
2428 uh
->source
, iph
->saddr
,
2430 } else if (skb
->pkt_type
== PACKET_HOST
) {
2431 sk
= __udp4_lib_demux_lookup(net
, uh
->dest
, iph
->daddr
,
2432 uh
->source
, iph
->saddr
, dif
, sdif
);
2435 if (!sk
|| !refcount_inc_not_zero(&sk
->sk_refcnt
))
2439 skb
->destructor
= sock_efree
;
2440 dst
= READ_ONCE(sk
->sk_rx_dst
);
2443 dst
= dst_check(dst
, 0);
2447 /* set noref for now.
2448 * any place which wants to hold dst has to call
2451 skb_dst_set_noref(skb
, dst
);
2453 /* for unconnected multicast sockets we need to validate
2454 * the source on each packet
2456 if (!inet_sk(sk
)->inet_daddr
&& in_dev
)
2457 return ip_mc_validate_source(skb
, iph
->daddr
,
2458 iph
->saddr
, iph
->tos
,
2459 skb
->dev
, in_dev
, &itag
);
2464 int udp_rcv(struct sk_buff
*skb
)
2466 return __udp4_lib_rcv(skb
, &udp_table
, IPPROTO_UDP
);
2469 void udp_destroy_sock(struct sock
*sk
)
2471 struct udp_sock
*up
= udp_sk(sk
);
2472 bool slow
= lock_sock_fast(sk
);
2473 udp_flush_pending_frames(sk
);
2474 unlock_sock_fast(sk
, slow
);
2475 if (static_branch_unlikely(&udp_encap_needed_key
)) {
2476 if (up
->encap_type
) {
2477 void (*encap_destroy
)(struct sock
*sk
);
2478 encap_destroy
= READ_ONCE(up
->encap_destroy
);
2482 if (up
->encap_enabled
)
2483 static_branch_dec(&udp_encap_needed_key
);
2488 * Socket option code for UDP
2490 int udp_lib_setsockopt(struct sock
*sk
, int level
, int optname
,
2491 char __user
*optval
, unsigned int optlen
,
2492 int (*push_pending_frames
)(struct sock
*))
2494 struct udp_sock
*up
= udp_sk(sk
);
2497 int is_udplite
= IS_UDPLITE(sk
);
2499 if (optlen
< sizeof(int))
2502 if (get_user(val
, (int __user
*)optval
))
2505 valbool
= val
? 1 : 0;
2514 push_pending_frames(sk
);
2522 case UDP_ENCAP_ESPINUDP
:
2523 case UDP_ENCAP_ESPINUDP_NON_IKE
:
2524 up
->encap_rcv
= xfrm4_udp_encap_rcv
;
2526 case UDP_ENCAP_L2TPINUDP
:
2527 up
->encap_type
= val
;
2529 udp_tunnel_encap_enable(sk
->sk_socket
);
2538 case UDP_NO_CHECK6_TX
:
2539 up
->no_check6_tx
= valbool
;
2542 case UDP_NO_CHECK6_RX
:
2543 up
->no_check6_rx
= valbool
;
2547 if (val
< 0 || val
> USHRT_MAX
)
2555 udp_tunnel_encap_enable(sk
->sk_socket
);
2556 up
->gro_enabled
= valbool
;
2561 * UDP-Lite's partial checksum coverage (RFC 3828).
2563 /* The sender sets actual checksum coverage length via this option.
2564 * The case coverage > packet length is handled by send module. */
2565 case UDPLITE_SEND_CSCOV
:
2566 if (!is_udplite
) /* Disable the option on UDP sockets */
2567 return -ENOPROTOOPT
;
2568 if (val
!= 0 && val
< 8) /* Illegal coverage: use default (8) */
2570 else if (val
> USHRT_MAX
)
2573 up
->pcflag
|= UDPLITE_SEND_CC
;
2576 /* The receiver specifies a minimum checksum coverage value. To make
2577 * sense, this should be set to at least 8 (as done below). If zero is
2578 * used, this again means full checksum coverage. */
2579 case UDPLITE_RECV_CSCOV
:
2580 if (!is_udplite
) /* Disable the option on UDP sockets */
2581 return -ENOPROTOOPT
;
2582 if (val
!= 0 && val
< 8) /* Avoid silly minimal values. */
2584 else if (val
> USHRT_MAX
)
2587 up
->pcflag
|= UDPLITE_RECV_CC
;
2597 EXPORT_SYMBOL(udp_lib_setsockopt
);
2599 int udp_setsockopt(struct sock
*sk
, int level
, int optname
,
2600 char __user
*optval
, unsigned int optlen
)
2602 if (level
== SOL_UDP
|| level
== SOL_UDPLITE
)
2603 return udp_lib_setsockopt(sk
, level
, optname
, optval
, optlen
,
2604 udp_push_pending_frames
);
2605 return ip_setsockopt(sk
, level
, optname
, optval
, optlen
);
2608 #ifdef CONFIG_COMPAT
2609 int compat_udp_setsockopt(struct sock
*sk
, int level
, int optname
,
2610 char __user
*optval
, unsigned int optlen
)
2612 if (level
== SOL_UDP
|| level
== SOL_UDPLITE
)
2613 return udp_lib_setsockopt(sk
, level
, optname
, optval
, optlen
,
2614 udp_push_pending_frames
);
2615 return compat_ip_setsockopt(sk
, level
, optname
, optval
, optlen
);
2619 int udp_lib_getsockopt(struct sock
*sk
, int level
, int optname
,
2620 char __user
*optval
, int __user
*optlen
)
2622 struct udp_sock
*up
= udp_sk(sk
);
2625 if (get_user(len
, optlen
))
2628 len
= min_t(unsigned int, len
, sizeof(int));
2639 val
= up
->encap_type
;
2642 case UDP_NO_CHECK6_TX
:
2643 val
= up
->no_check6_tx
;
2646 case UDP_NO_CHECK6_RX
:
2647 val
= up
->no_check6_rx
;
2654 /* The following two cannot be changed on UDP sockets, the return is
2655 * always 0 (which corresponds to the full checksum coverage of UDP). */
2656 case UDPLITE_SEND_CSCOV
:
2660 case UDPLITE_RECV_CSCOV
:
2665 return -ENOPROTOOPT
;
2668 if (put_user(len
, optlen
))
2670 if (copy_to_user(optval
, &val
, len
))
2674 EXPORT_SYMBOL(udp_lib_getsockopt
);
2676 int udp_getsockopt(struct sock
*sk
, int level
, int optname
,
2677 char __user
*optval
, int __user
*optlen
)
2679 if (level
== SOL_UDP
|| level
== SOL_UDPLITE
)
2680 return udp_lib_getsockopt(sk
, level
, optname
, optval
, optlen
);
2681 return ip_getsockopt(sk
, level
, optname
, optval
, optlen
);
2684 #ifdef CONFIG_COMPAT
2685 int compat_udp_getsockopt(struct sock
*sk
, int level
, int optname
,
2686 char __user
*optval
, int __user
*optlen
)
2688 if (level
== SOL_UDP
|| level
== SOL_UDPLITE
)
2689 return udp_lib_getsockopt(sk
, level
, optname
, optval
, optlen
);
2690 return compat_ip_getsockopt(sk
, level
, optname
, optval
, optlen
);
2694 * udp_poll - wait for a UDP event.
2695 * @file - file struct
2697 * @wait - poll table
2699 * This is same as datagram poll, except for the special case of
2700 * blocking sockets. If application is using a blocking fd
2701 * and a packet with checksum error is in the queue;
2702 * then it could get return from select indicating data available
2703 * but then block when reading it. Add special case code
2704 * to work around these arguably broken applications.
2706 __poll_t
udp_poll(struct file
*file
, struct socket
*sock
, poll_table
*wait
)
2708 __poll_t mask
= datagram_poll(file
, sock
, wait
);
2709 struct sock
*sk
= sock
->sk
;
2711 if (!skb_queue_empty(&udp_sk(sk
)->reader_queue
))
2712 mask
|= EPOLLIN
| EPOLLRDNORM
;
2714 /* Check for false positives due to checksum errors */
2715 if ((mask
& EPOLLRDNORM
) && !(file
->f_flags
& O_NONBLOCK
) &&
2716 !(sk
->sk_shutdown
& RCV_SHUTDOWN
) && first_packet_length(sk
) == -1)
2717 mask
&= ~(EPOLLIN
| EPOLLRDNORM
);
2722 EXPORT_SYMBOL(udp_poll
);
2724 int udp_abort(struct sock
*sk
, int err
)
2729 sk
->sk_error_report(sk
);
2730 __udp_disconnect(sk
, 0);
2736 EXPORT_SYMBOL_GPL(udp_abort
);
2738 struct proto udp_prot
= {
2740 .owner
= THIS_MODULE
,
2741 .close
= udp_lib_close
,
2742 .pre_connect
= udp_pre_connect
,
2743 .connect
= ip4_datagram_connect
,
2744 .disconnect
= udp_disconnect
,
2746 .init
= udp_init_sock
,
2747 .destroy
= udp_destroy_sock
,
2748 .setsockopt
= udp_setsockopt
,
2749 .getsockopt
= udp_getsockopt
,
2750 .sendmsg
= udp_sendmsg
,
2751 .recvmsg
= udp_recvmsg
,
2752 .sendpage
= udp_sendpage
,
2753 .release_cb
= ip4_datagram_release_cb
,
2754 .hash
= udp_lib_hash
,
2755 .unhash
= udp_lib_unhash
,
2756 .rehash
= udp_v4_rehash
,
2757 .get_port
= udp_v4_get_port
,
2758 .memory_allocated
= &udp_memory_allocated
,
2759 .sysctl_mem
= sysctl_udp_mem
,
2760 .sysctl_wmem_offset
= offsetof(struct net
, ipv4
.sysctl_udp_wmem_min
),
2761 .sysctl_rmem_offset
= offsetof(struct net
, ipv4
.sysctl_udp_rmem_min
),
2762 .obj_size
= sizeof(struct udp_sock
),
2763 .h
.udp_table
= &udp_table
,
2764 #ifdef CONFIG_COMPAT
2765 .compat_setsockopt
= compat_udp_setsockopt
,
2766 .compat_getsockopt
= compat_udp_getsockopt
,
2768 .diag_destroy
= udp_abort
,
2770 EXPORT_SYMBOL(udp_prot
);
2772 /* ------------------------------------------------------------------------ */
2773 #ifdef CONFIG_PROC_FS
2775 static struct sock
*udp_get_first(struct seq_file
*seq
, int start
)
2778 struct udp_seq_afinfo
*afinfo
= PDE_DATA(file_inode(seq
->file
));
2779 struct udp_iter_state
*state
= seq
->private;
2780 struct net
*net
= seq_file_net(seq
);
2782 for (state
->bucket
= start
; state
->bucket
<= afinfo
->udp_table
->mask
;
2784 struct udp_hslot
*hslot
= &afinfo
->udp_table
->hash
[state
->bucket
];
2786 if (hlist_empty(&hslot
->head
))
2789 spin_lock_bh(&hslot
->lock
);
2790 sk_for_each(sk
, &hslot
->head
) {
2791 if (!net_eq(sock_net(sk
), net
))
2793 if (sk
->sk_family
== afinfo
->family
)
2796 spin_unlock_bh(&hslot
->lock
);
2803 static struct sock
*udp_get_next(struct seq_file
*seq
, struct sock
*sk
)
2805 struct udp_seq_afinfo
*afinfo
= PDE_DATA(file_inode(seq
->file
));
2806 struct udp_iter_state
*state
= seq
->private;
2807 struct net
*net
= seq_file_net(seq
);
2811 } while (sk
&& (!net_eq(sock_net(sk
), net
) || sk
->sk_family
!= afinfo
->family
));
2814 if (state
->bucket
<= afinfo
->udp_table
->mask
)
2815 spin_unlock_bh(&afinfo
->udp_table
->hash
[state
->bucket
].lock
);
2816 return udp_get_first(seq
, state
->bucket
+ 1);
2821 static struct sock
*udp_get_idx(struct seq_file
*seq
, loff_t pos
)
2823 struct sock
*sk
= udp_get_first(seq
, 0);
2826 while (pos
&& (sk
= udp_get_next(seq
, sk
)) != NULL
)
2828 return pos
? NULL
: sk
;
2831 void *udp_seq_start(struct seq_file
*seq
, loff_t
*pos
)
2833 struct udp_iter_state
*state
= seq
->private;
2834 state
->bucket
= MAX_UDP_PORTS
;
2836 return *pos
? udp_get_idx(seq
, *pos
-1) : SEQ_START_TOKEN
;
2838 EXPORT_SYMBOL(udp_seq_start
);
2840 void *udp_seq_next(struct seq_file
*seq
, void *v
, loff_t
*pos
)
2844 if (v
== SEQ_START_TOKEN
)
2845 sk
= udp_get_idx(seq
, 0);
2847 sk
= udp_get_next(seq
, v
);
2852 EXPORT_SYMBOL(udp_seq_next
);
2854 void udp_seq_stop(struct seq_file
*seq
, void *v
)
2856 struct udp_seq_afinfo
*afinfo
= PDE_DATA(file_inode(seq
->file
));
2857 struct udp_iter_state
*state
= seq
->private;
2859 if (state
->bucket
<= afinfo
->udp_table
->mask
)
2860 spin_unlock_bh(&afinfo
->udp_table
->hash
[state
->bucket
].lock
);
2862 EXPORT_SYMBOL(udp_seq_stop
);
2864 /* ------------------------------------------------------------------------ */
2865 static void udp4_format_sock(struct sock
*sp
, struct seq_file
*f
,
2868 struct inet_sock
*inet
= inet_sk(sp
);
2869 __be32 dest
= inet
->inet_daddr
;
2870 __be32 src
= inet
->inet_rcv_saddr
;
2871 __u16 destp
= ntohs(inet
->inet_dport
);
2872 __u16 srcp
= ntohs(inet
->inet_sport
);
2874 seq_printf(f
, "%5d: %08X:%04X %08X:%04X"
2875 " %02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %u",
2876 bucket
, src
, srcp
, dest
, destp
, sp
->sk_state
,
2877 sk_wmem_alloc_get(sp
),
2880 from_kuid_munged(seq_user_ns(f
), sock_i_uid(sp
)),
2882 refcount_read(&sp
->sk_refcnt
), sp
,
2883 atomic_read(&sp
->sk_drops
));
2886 int udp4_seq_show(struct seq_file
*seq
, void *v
)
2888 seq_setwidth(seq
, 127);
2889 if (v
== SEQ_START_TOKEN
)
2890 seq_puts(seq
, " sl local_address rem_address st tx_queue "
2891 "rx_queue tr tm->when retrnsmt uid timeout "
2892 "inode ref pointer drops");
2894 struct udp_iter_state
*state
= seq
->private;
2896 udp4_format_sock(v
, seq
, state
->bucket
);
2902 const struct seq_operations udp_seq_ops
= {
2903 .start
= udp_seq_start
,
2904 .next
= udp_seq_next
,
2905 .stop
= udp_seq_stop
,
2906 .show
= udp4_seq_show
,
2908 EXPORT_SYMBOL(udp_seq_ops
);
2910 static struct udp_seq_afinfo udp4_seq_afinfo
= {
2912 .udp_table
= &udp_table
,
2915 static int __net_init
udp4_proc_init_net(struct net
*net
)
2917 if (!proc_create_net_data("udp", 0444, net
->proc_net
, &udp_seq_ops
,
2918 sizeof(struct udp_iter_state
), &udp4_seq_afinfo
))
2923 static void __net_exit
udp4_proc_exit_net(struct net
*net
)
2925 remove_proc_entry("udp", net
->proc_net
);
2928 static struct pernet_operations udp4_net_ops
= {
2929 .init
= udp4_proc_init_net
,
2930 .exit
= udp4_proc_exit_net
,
2933 int __init
udp4_proc_init(void)
2935 return register_pernet_subsys(&udp4_net_ops
);
2938 void udp4_proc_exit(void)
2940 unregister_pernet_subsys(&udp4_net_ops
);
2942 #endif /* CONFIG_PROC_FS */
2944 static __initdata
unsigned long uhash_entries
;
2945 static int __init
set_uhash_entries(char *str
)
2952 ret
= kstrtoul(str
, 0, &uhash_entries
);
2956 if (uhash_entries
&& uhash_entries
< UDP_HTABLE_SIZE_MIN
)
2957 uhash_entries
= UDP_HTABLE_SIZE_MIN
;
2960 __setup("uhash_entries=", set_uhash_entries
);
2962 void __init
udp_table_init(struct udp_table
*table
, const char *name
)
2966 table
->hash
= alloc_large_system_hash(name
,
2967 2 * sizeof(struct udp_hslot
),
2969 21, /* one slot per 2 MB */
2973 UDP_HTABLE_SIZE_MIN
,
2976 table
->hash2
= table
->hash
+ (table
->mask
+ 1);
2977 for (i
= 0; i
<= table
->mask
; i
++) {
2978 INIT_HLIST_HEAD(&table
->hash
[i
].head
);
2979 table
->hash
[i
].count
= 0;
2980 spin_lock_init(&table
->hash
[i
].lock
);
2982 for (i
= 0; i
<= table
->mask
; i
++) {
2983 INIT_HLIST_HEAD(&table
->hash2
[i
].head
);
2984 table
->hash2
[i
].count
= 0;
2985 spin_lock_init(&table
->hash2
[i
].lock
);
2989 u32
udp_flow_hashrnd(void)
2991 static u32 hashrnd __read_mostly
;
2993 net_get_random_once(&hashrnd
, sizeof(hashrnd
));
2997 EXPORT_SYMBOL(udp_flow_hashrnd
);
2999 static void __udp_sysctl_init(struct net
*net
)
3001 net
->ipv4
.sysctl_udp_rmem_min
= SK_MEM_QUANTUM
;
3002 net
->ipv4
.sysctl_udp_wmem_min
= SK_MEM_QUANTUM
;
3004 #ifdef CONFIG_NET_L3_MASTER_DEV
3005 net
->ipv4
.sysctl_udp_l3mdev_accept
= 0;
3009 static int __net_init
udp_sysctl_init(struct net
*net
)
3011 __udp_sysctl_init(net
);
3015 static struct pernet_operations __net_initdata udp_sysctl_ops
= {
3016 .init
= udp_sysctl_init
,
3019 void __init
udp_init(void)
3021 unsigned long limit
;
3024 udp_table_init(&udp_table
, "UDP");
3025 limit
= nr_free_buffer_pages() / 8;
3026 limit
= max(limit
, 128UL);
3027 sysctl_udp_mem
[0] = limit
/ 4 * 3;
3028 sysctl_udp_mem
[1] = limit
;
3029 sysctl_udp_mem
[2] = sysctl_udp_mem
[0] * 2;
3031 __udp_sysctl_init(&init_net
);
3033 /* 16 spinlocks per cpu */
3034 udp_busylocks_log
= ilog2(nr_cpu_ids
) + 4;
3035 udp_busylocks
= kmalloc(sizeof(spinlock_t
) << udp_busylocks_log
,
3038 panic("UDP: failed to alloc udp_busylocks\n");
3039 for (i
= 0; i
< (1U << udp_busylocks_log
); i
++)
3040 spin_lock_init(udp_busylocks
+ i
);
3042 if (register_pernet_subsys(&udp_sysctl_ops
))
3043 panic("UDP: failed to init sysctl parameters.\n");