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wifi: mac80211: switch airtime fairness back to deficit round-robin scheduling
[linux-block.git] / net / ipv4 / udp.c
CommitLineData
2874c5fd 1// SPDX-License-Identifier: GPL-2.0-or-later
1da177e4
LT		 2/*
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.
6 *
7 * The User Datagram Protocol (UDP).
8 *
02c30a84 9 * Authors: Ross Biro
1da177e4
LT		 10 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
11 * Arnt Gulbrandsen, <agulbra@nvg.unit.no>
113aa838 12 * Alan Cox, <alan@lxorguk.ukuu.org.uk>
1da177e4
LT		 13 * Hirokazu Takahashi, <taka@valinux.co.jp>
14 *
15 * Fixes:
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
e905a9ed
YH		 22 * Alan Cox : Tidied select() semantics.
23 * Alan Cox : udp_err() fixed properly, also now
1da177e4
LT		 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
29 * does NOT close.
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
e905a9ed 58 * for connect.
1da177e4
LT		 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
65 * datagrams.
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
342f0234 72 * James Chapman : Add L2TP encapsulation type.
1da177e4 73 */
e905a9ed 74
afd46503
JP		 75#define pr_fmt(fmt) "UDP: " fmt
76
aef2feda 77#include <linux/bpf-cgroup.h>
7c0f6ba6 78#include <linux/uaccess.h>
1da177e4 79#include <asm/ioctls.h>
57c8a661 80#include <linux/memblock.h>
8203efb3 81#include <linux/highmem.h>
1da177e4
LT		 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>
14c85021 87#include <linux/igmp.h>
6e540309 88#include <linux/inetdevice.h>
1da177e4
LT		 89#include <linux/in.h>
90#include <linux/errno.h>
91#include <linux/timer.h>
92#include <linux/mm.h>
1da177e4 93#include <linux/inet.h>
1da177e4 94#include <linux/netdevice.h>
5a0e3ad6 95#include <linux/slab.h>
c752f073 96#include <net/tcp_states.h>
1da177e4
LT		 97#include <linux/skbuff.h>
98#include <linux/proc_fs.h>
99#include <linux/seq_file.h>
457c4cbc 100#include <net/net_namespace.h>
1da177e4 101#include <net/icmp.h>
421b3885 102#include <net/inet_hashtables.h>
e7cc0824 103#include <net/ip_tunnels.h>
1da177e4 104#include <net/route.h>
1da177e4
LT		 105#include <net/checksum.h>
106#include <net/xfrm.h>
296f7ea7 107#include <trace/events/udp.h>
447167bf 108#include <linux/static_key.h>
951cf368 109#include <linux/btf_ids.h>
22911fc5 110#include <trace/events/skb.h>
076bb0c8 111#include <net/busy_poll.h>
ba4e58ec 112#include "udp_impl.h"
e32ea7e7 113#include <net/sock_reuseport.h>
217375a0 114#include <net/addrconf.h>
60fb9567 115#include <net/udp_tunnel.h>
0146dca7
SD		 116#if IS_ENABLED(CONFIG_IPV6)
117#include <net/ipv6_stubs.h>
118#endif
1da177e4 119
f86dcc5a 120struct udp_table udp_table __read_mostly;
645ca708 121EXPORT_SYMBOL(udp_table);
1da177e4 122
8d987e5c 123long sysctl_udp_mem[3] __read_mostly;
95766fff 124EXPORT_SYMBOL(sysctl_udp_mem);
c482c568 125
91b6d325 126atomic_long_t udp_memory_allocated ____cacheline_aligned_in_smp;
95766fff 127EXPORT_SYMBOL(udp_memory_allocated);
0defbb0a
ED		 128DEFINE_PER_CPU(int, udp_memory_per_cpu_fw_alloc);
129EXPORT_PER_CPU_SYMBOL_GPL(udp_memory_per_cpu_fw_alloc);
95766fff 130
f86dcc5a
ED		 131#define MAX_UDP_PORTS 65536
132#define PORTS_PER_CHAIN (MAX_UDP_PORTS / UDP_HTABLE_SIZE_MIN)
98322f22 133
f24d43c0 134static int udp_lib_lport_inuse(struct net *net, __u16 num,
645ca708 135 const struct udp_hslot *hslot,
98322f22 136 unsigned long *bitmap,
fe38d2a1 137 struct sock *sk, unsigned int log)
1da177e4 138{
f24d43c0 139 struct sock *sk2;
ba418fa3 140 kuid_t uid = sock_i_uid(sk);
25030a7f 141
ca065d0c 142 sk_for_each(sk2, &hslot->head) {
9d4fb27d
JP		 143 if (net_eq(sock_net(sk2), net) &&
144 sk2 != sk &&
d4cada4a 145 (bitmap || udp_sk(sk2)->udp_port_hash == num) &&
9d4fb27d
JP		 146 (!sk2->sk_reuse || !sk->sk_reuse) &&
147 (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if ||
148 sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
fe38d2a1 149 inet_rcv_saddr_equal(sk, sk2, true)) {
df560056
EG		 150 if (sk2->sk_reuseport && sk->sk_reuseport &&
151 !rcu_access_pointer(sk->sk_reuseport_cb) &&
152 uid_eq(uid, sock_i_uid(sk2))) {
153 if (!bitmap)
154 return 0;
155 } else {
156 if (!bitmap)
157 return 1;
158 __set_bit(udp_sk(sk2)->udp_port_hash >> log,
159 bitmap);
160 }
98322f22 161 }
4243cdc2 162 }
25030a7f
GR		 163 return 0;
164}
165
30fff923
ED		 166/*
167 * Note: we still hold spinlock of primary hash chain, so no other writer
168 * can insert/delete a socket with local_port == num
169 */
170static int udp_lib_lport_inuse2(struct net *net, __u16 num,
4243cdc2 171 struct udp_hslot *hslot2,
fe38d2a1 172 struct sock *sk)
30fff923
ED		 173{
174 struct sock *sk2;
ba418fa3 175 kuid_t uid = sock_i_uid(sk);
30fff923
ED		 176 int res = 0;
177
178 spin_lock(&hslot2->lock);
ca065d0c 179 udp_portaddr_for_each_entry(sk2, &hslot2->head) {
9d4fb27d
JP		 180 if (net_eq(sock_net(sk2), net) &&
181 sk2 != sk &&
182 (udp_sk(sk2)->udp_port_hash == num) &&
183 (!sk2->sk_reuse || !sk->sk_reuse) &&
184 (!sk2->sk_bound_dev_if || !sk->sk_bound_dev_if ||
185 sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
fe38d2a1 186 inet_rcv_saddr_equal(sk, sk2, true)) {
df560056
EG		 187 if (sk2->sk_reuseport && sk->sk_reuseport &&
188 !rcu_access_pointer(sk->sk_reuseport_cb) &&
189 uid_eq(uid, sock_i_uid(sk2))) {
190 res = 0;
191 } else {
192 res = 1;
193 }
30fff923
ED		 194 break;
195 }
4243cdc2 196 }
30fff923
ED		 197 spin_unlock(&hslot2->lock);
198 return res;
199}
200
fe38d2a1 201static int udp_reuseport_add_sock(struct sock *sk, struct udp_hslot *hslot)
e32ea7e7
CG		 202{
203 struct net *net = sock_net(sk);
e32ea7e7
CG		 204 kuid_t uid = sock_i_uid(sk);
205 struct sock *sk2;
206
ca065d0c 207 sk_for_each(sk2, &hslot->head) {
e32ea7e7
CG		 208 if (net_eq(sock_net(sk2), net) &&
209 sk2 != sk &&
210 sk2->sk_family == sk->sk_family &&
211 ipv6_only_sock(sk2) == ipv6_only_sock(sk) &&
212 (udp_sk(sk2)->udp_port_hash == udp_sk(sk)->udp_port_hash) &&
213 (sk2->sk_bound_dev_if == sk->sk_bound_dev_if) &&
214 sk2->sk_reuseport && uid_eq(uid, sock_i_uid(sk2)) &&
fe38d2a1 215 inet_rcv_saddr_equal(sk, sk2, false)) {
2dbb9b9e
MKL		 216 return reuseport_add_sock(sk, sk2,
217 inet_rcv_saddr_any(sk));
e32ea7e7
CG		 218 }
219 }
220
2dbb9b9e 221 return reuseport_alloc(sk, inet_rcv_saddr_any(sk));
e32ea7e7
CG		 222}
223
25030a7f 224/**
6ba5a3c5 225 * udp_lib_get_port - UDP/-Lite port lookup for IPv4 and IPv6
25030a7f
GR		 226 *
227 * @sk: socket struct in question
228 * @snum: port number to look up
25985edc 229 * @hash2_nulladdr: AF-dependent hash value in secondary hash chains,
30fff923 230 * with NULL address
25030a7f 231 */
6ba5a3c5 232int udp_lib_get_port(struct sock *sk, unsigned short snum,
30fff923 233 unsigned int hash2_nulladdr)
25030a7f 234{
512615b6 235 struct udp_hslot *hslot, *hslot2;
645ca708 236 struct udp_table *udptable = sk->sk_prot->h.udp_table;
25030a7f 237 int error = 1;
3b1e0a65 238 struct net *net = sock_net(sk);
1da177e4 239
32c1da70 240 if (!snum) {
9088c560 241 int low, high, remaining;
95c96174 242 unsigned int rand;
98322f22
ED		 243 unsigned short first, last;
244 DECLARE_BITMAP(bitmap, PORTS_PER_CHAIN);
32c1da70 245
0bbf87d8 246 inet_get_local_port_range(net, &low, &high);
a25de534 247 remaining = (high - low) + 1;
227b60f5 248
63862b5b 249 rand = prandom_u32();
8fc54f68 250 first = reciprocal_scale(rand, remaining) + low;
98322f22
ED		 251 /*
252 * force rand to be an odd multiple of UDP_HTABLE_SIZE
253 */
f86dcc5a 254 rand = (rand | 1) * (udptable->mask + 1);
5781b235
ED		 255 last = first + udptable->mask + 1;
256 do {
f86dcc5a 257 hslot = udp_hashslot(udptable, net, first);
98322f22 258 bitmap_zero(bitmap, PORTS_PER_CHAIN);
645ca708 259 spin_lock_bh(&hslot->lock);
98322f22 260 udp_lib_lport_inuse(net, snum, hslot, bitmap, sk,
fe38d2a1 261 udptable->log);
98322f22
ED		 262
263 snum = first;
264 /*
265 * Iterate on all possible values of snum for this hash.
266 * Using steps of an odd multiple of UDP_HTABLE_SIZE
267 * give us randomization and full range coverage.
268 */
9088c560 269 do {
98322f22 270 if (low <= snum && snum <= high &&
e3826f1e 271 !test_bit(snum >> udptable->log, bitmap) &&
122ff243 272 !inet_is_local_reserved_port(net, snum))
98322f22
ED		 273 goto found;
274 snum += rand;
275 } while (snum != first);
276 spin_unlock_bh(&hslot->lock);
df560056 277 cond_resched();
5781b235 278 } while (++first != last);
98322f22 279 goto fail;
645ca708 280 } else {
f86dcc5a 281 hslot = udp_hashslot(udptable, net, snum);
645ca708 282 spin_lock_bh(&hslot->lock);
30fff923
ED		 283 if (hslot->count > 10) {
284 int exist;
285 unsigned int slot2 = udp_sk(sk)->udp_portaddr_hash ^ snum;
286
287 slot2 &= udptable->mask;
288 hash2_nulladdr &= udptable->mask;
289
290 hslot2 = udp_hashslot2(udptable, slot2);
291 if (hslot->count < hslot2->count)
292 goto scan_primary_hash;
293
fe38d2a1 294 exist = udp_lib_lport_inuse2(net, snum, hslot2, sk);
30fff923
ED		 295 if (!exist && (hash2_nulladdr != slot2)) {
296 hslot2 = udp_hashslot2(udptable, hash2_nulladdr);
297 exist = udp_lib_lport_inuse2(net, snum, hslot2,
fe38d2a1 298 sk);
30fff923
ED		 299 }
300 if (exist)
301 goto fail_unlock;
302 else
303 goto found;
304 }
305scan_primary_hash:
fe38d2a1 306 if (udp_lib_lport_inuse(net, snum, hslot, NULL, sk, 0))
645ca708
ED		 307 goto fail_unlock;
308 }
98322f22 309found:
c720c7e8 310 inet_sk(sk)->inet_num = snum;
d4cada4a
ED		 311 udp_sk(sk)->udp_port_hash = snum;
312 udp_sk(sk)->udp_portaddr_hash ^= snum;
1da177e4 313 if (sk_unhashed(sk)) {
e32ea7e7 314 if (sk->sk_reuseport &&
fe38d2a1 315 udp_reuseport_add_sock(sk, hslot)) {
e32ea7e7
CG		 316 inet_sk(sk)->inet_num = 0;
317 udp_sk(sk)->udp_port_hash = 0;
318 udp_sk(sk)->udp_portaddr_hash ^= snum;
319 goto fail_unlock;
320 }
321
ca065d0c 322 sk_add_node_rcu(sk, &hslot->head);
fdcc8aa9 323 hslot->count++;
c29a0bc4 324 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
512615b6
ED		 325
326 hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash);
327 spin_lock(&hslot2->lock);
d894ba18 328 if (IS_ENABLED(CONFIG_IPV6) && sk->sk_reuseport &&
1602f49b
DM		 329 sk->sk_family == AF_INET6)
330 hlist_add_tail_rcu(&udp_sk(sk)->udp_portaddr_node,
331 &hslot2->head);
d894ba18 332 else
1602f49b
DM		 333 hlist_add_head_rcu(&udp_sk(sk)->udp_portaddr_node,
334 &hslot2->head);
512615b6
ED		 335 hslot2->count++;
336 spin_unlock(&hslot2->lock);
1da177e4 337 }
ca065d0c 338 sock_set_flag(sk, SOCK_RCU_FREE);
25030a7f 339 error = 0;
645ca708
ED		 340fail_unlock:
341 spin_unlock_bh(&hslot->lock);
1da177e4 342fail:
25030a7f
GR		 343 return error;
344}
c482c568 345EXPORT_SYMBOL(udp_lib_get_port);
25030a7f 346
6ba5a3c5 347int udp_v4_get_port(struct sock *sk, unsigned short snum)
db8dac20 348{
30fff923 349 unsigned int hash2_nulladdr =
f0b1e64c 350 ipv4_portaddr_hash(sock_net(sk), htonl(INADDR_ANY), snum);
30fff923 351 unsigned int hash2_partial =
f0b1e64c 352 ipv4_portaddr_hash(sock_net(sk), inet_sk(sk)->inet_rcv_saddr, 0);
30fff923 353
d4cada4a 354 /* precompute partial secondary hash */
30fff923 355 udp_sk(sk)->udp_portaddr_hash = hash2_partial;
fe38d2a1 356 return udp_lib_get_port(sk, snum, hash2_nulladdr);
db8dac20
DM		 357}
358
d1e37288
SX		 359static int compute_score(struct sock *sk, struct net *net,
360 __be32 saddr, __be16 sport,
fb74c277 361 __be32 daddr, unsigned short hnum,
73545373 362 int dif, int sdif)
645ca708 363{
60c04aec
JP		 364 int score;
365 struct inet_sock *inet;
6da5b0f0 366 bool dev_match;
645ca708 367
60c04aec
JP		 368 if (!net_eq(sock_net(sk), net) ||
369 udp_sk(sk)->udp_port_hash != hnum ||
370 ipv6_only_sock(sk))
371 return -1;
645ca708 372
4cdeeee9
PO		 373 if (sk->sk_rcv_saddr != daddr)
374 return -1;
60c04aec 375
4cdeeee9 376 score = (sk->sk_family == PF_INET) ? 2 : 1;
60c04aec 377
4cdeeee9 378 inet = inet_sk(sk);
60c04aec
JP		 379 if (inet->inet_daddr) {
380 if (inet->inet_daddr != saddr)
381 return -1;
382 score += 4;
383 }
384
385 if (inet->inet_dport) {
386 if (inet->inet_dport != sport)
387 return -1;
388 score += 4;
389 }
390
6da5b0f0
MM		 391 dev_match = udp_sk_bound_dev_eq(net, sk->sk_bound_dev_if,
392 dif, sdif);
393 if (!dev_match)
394 return -1;
8d6c414c
MM		 395 if (sk->sk_bound_dev_if)
396 score += 4;
fb74c277 397
7170a977 398 if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id())
70da268b 399 score++;
645ca708
ED		 400 return score;
401}
402
6eada011
ED		 403static u32 udp_ehashfn(const struct net *net, const __be32 laddr,
404 const __u16 lport, const __be32 faddr,
405 const __be16 fport)
65cd8033 406{
1bbdceef
HFS		 407 static u32 udp_ehash_secret __read_mostly;
408
409 net_get_random_once(&udp_ehash_secret, sizeof(udp_ehash_secret));
410
65cd8033 411 return __inet_ehashfn(laddr, lport, faddr, fport,
1bbdceef 412 udp_ehash_secret + net_hash_mix(net));
65cd8033
HFS		 413}
414
a57066b1
DM		 415static struct sock *lookup_reuseport(struct net *net, struct sock *sk,
416 struct sk_buff *skb,
417 __be32 saddr, __be16 sport,
418 __be32 daddr, unsigned short hnum)
7629c73a
JS		 419{
420 struct sock *reuse_sk = NULL;
421 u32 hash;
422
423 if (sk->sk_reuseport && sk->sk_state != TCP_ESTABLISHED) {
424 hash = udp_ehashfn(net, daddr, hnum, saddr, sport);
425 reuse_sk = reuseport_select_sock(sk, hash, skb,
426 sizeof(struct udphdr));
7629c73a
JS		 427 }
428 return reuse_sk;
429}
430
d1e37288 431/* called with rcu_read_lock() */
5051ebd2 432static struct sock *udp4_lib_lookup2(struct net *net,
fb74c277
DA		 433 __be32 saddr, __be16 sport,
434 __be32 daddr, unsigned int hnum,
73545373 435 int dif, int sdif,
fb74c277
DA		 436 struct udp_hslot *hslot2,
437 struct sk_buff *skb)
5051ebd2
ED		 438{
439 struct sock *sk, *result;
e94a62f5 440 int score, badness;
5051ebd2 441
5051ebd2 442 result = NULL;
ba418fa3 443 badness = 0;
ca065d0c 444 udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
d1e37288 445 score = compute_score(sk, net, saddr, sport,
73545373 446 daddr, hnum, dif, sdif);
5051ebd2 447 if (score > badness) {
7629c73a
JS		 448 result = lookup_reuseport(net, sk, skb,
449 saddr, sport, daddr, hnum);
a57066b1
DM		 450 /* Fall back to scoring if group has connections */
451 if (result && !reuseport_has_conns(sk, false))
7629c73a
JS		 452 return result;
453
a57066b1 454 result = result ? : sk;
ca065d0c 455 badness = score;
5051ebd2
ED		 456 }
457 }
5051ebd2
ED		 458 return result;
459}
460
a57066b1
DM		 461static struct sock *udp4_lookup_run_bpf(struct net *net,
462 struct udp_table *udptable,
463 struct sk_buff *skb,
464 __be32 saddr, __be16 sport,
f8931565 465 __be32 daddr, u16 hnum, const int dif)
72f7e944
JS		 466{
467 struct sock *sk, *reuse_sk;
468 bool no_reuseport;
469
470 if (udptable != &udp_table)
471 return NULL; /* only UDP is supported */
472
f8931565
MP		 473 no_reuseport = bpf_sk_lookup_run_v4(net, IPPROTO_UDP, saddr, sport,
474 daddr, hnum, dif, &sk);
72f7e944
JS		 475 if (no_reuseport || IS_ERR_OR_NULL(sk))
476 return sk;
477
478 reuse_sk = lookup_reuseport(net, sk, skb, saddr, sport, daddr, hnum);
c64c9c28 479 if (reuse_sk)
72f7e944
JS		 480 sk = reuse_sk;
481 return sk;
482}
483
db8dac20
DM		 484/* UDP is nearly always wildcards out the wazoo, it makes no sense to try
485 * harder than this. -DaveM
486 */
fce82338 487struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr,
fb74c277
DA		 488 __be16 sport, __be32 daddr, __be16 dport, int dif,
489 int sdif, struct udp_table *udptable, struct sk_buff *skb)
db8dac20 490{
db8dac20 491 unsigned short hnum = ntohs(dport);
4cdeeee9
PO		 492 unsigned int hash2, slot2;
493 struct udp_hslot *hslot2;
72f7e944 494 struct sock *result, *sk;
645ca708 495
4cdeeee9
PO		 496 hash2 = ipv4_portaddr_hash(net, daddr, hnum);
497 slot2 = hash2 & udptable->mask;
498 hslot2 = &udptable->hash2[slot2];
499
72f7e944 500 /* Lookup connected or non-wildcard socket */
4cdeeee9
PO		 501 result = udp4_lib_lookup2(net, saddr, sport,
502 daddr, hnum, dif, sdif,
73545373 503 hslot2, skb);
72f7e944
JS		 504 if (!IS_ERR_OR_NULL(result) && result->sk_state == TCP_ESTABLISHED)
505 goto done;
506
507 /* Lookup redirect from BPF */
508 if (static_branch_unlikely(&bpf_sk_lookup_enabled)) {
509 sk = udp4_lookup_run_bpf(net, udptable, skb,
f8931565 510 saddr, sport, daddr, hnum, dif);
72f7e944
JS		 511 if (sk) {
512 result = sk;
513 goto done;
514 }
db8dac20 515 }
72f7e944
JS		 516
517 /* Got non-wildcard socket or error on first lookup */
518 if (result)
519 goto done;
520
521 /* Lookup wildcard sockets */
522 hash2 = ipv4_portaddr_hash(net, htonl(INADDR_ANY), hnum);
523 slot2 = hash2 & udptable->mask;
524 hslot2 = &udptable->hash2[slot2];
525
526 result = udp4_lib_lookup2(net, saddr, sport,
527 htonl(INADDR_ANY), hnum, dif, sdif,
528 hslot2, skb);
529done:
88e235b8 530 if (IS_ERR(result))
4cdeeee9 531 return NULL;
db8dac20
DM		 532 return result;
533}
fce82338 534EXPORT_SYMBOL_GPL(__udp4_lib_lookup);
db8dac20 535
607c4aaf
KK		 536static inline struct sock *__udp4_lib_lookup_skb(struct sk_buff *skb,
537 __be16 sport, __be16 dport,
645ca708 538 struct udp_table *udptable)
607c4aaf
KK		 539{
540 const struct iphdr *iph = ip_hdr(skb);
541
ed7cbbce 542 return __udp4_lib_lookup(dev_net(skb->dev), iph->saddr, sport,
8afdd99a 543 iph->daddr, dport, inet_iif(skb),
fb74c277 544 inet_sdif(skb), udptable, skb);
607c4aaf
KK		 545}
546
7b58e63e 547struct sock *udp4_lib_lookup_skb(const struct sk_buff *skb,
63058308
TH		 548 __be16 sport, __be16 dport)
549{
257a525f
MKL		 550 const struct iphdr *iph = ip_hdr(skb);
551
552 return __udp4_lib_lookup(dev_net(skb->dev), iph->saddr, sport,
553 iph->daddr, dport, inet_iif(skb),
554 inet_sdif(skb), &udp_table, NULL);
63058308 555}
63058308 556
ca065d0c
ED		 557/* Must be called under rcu_read_lock().
558 * Does increment socket refcount.
559 */
6e86000c 560#if IS_ENABLED(CONFIG_NF_TPROXY_IPV4) || IS_ENABLED(CONFIG_NF_SOCKET_IPV4)
bcd41303
KK		 561struct sock *udp4_lib_lookup(struct net *net, __be32 saddr, __be16 sport,
562 __be32 daddr, __be16 dport, int dif)
563{
ca065d0c
ED		 564 struct sock *sk;
565
566 sk = __udp4_lib_lookup(net, saddr, sport, daddr, dport,
fb74c277 567 dif, 0, &udp_table, NULL);
41c6d650 568 if (sk && !refcount_inc_not_zero(&sk->sk_refcnt))
ca065d0c
ED		 569 sk = NULL;
570 return sk;
bcd41303
KK		 571}
572EXPORT_SYMBOL_GPL(udp4_lib_lookup);
ca065d0c 573#endif
bcd41303 574
421b3885
SB		 575static inline bool __udp_is_mcast_sock(struct net *net, struct sock *sk,
576 __be16 loc_port, __be32 loc_addr,
577 __be16 rmt_port, __be32 rmt_addr,
fb74c277 578 int dif, int sdif, unsigned short hnum)
421b3885
SB		 579{
580 struct inet_sock *inet = inet_sk(sk);
581
582 if (!net_eq(sock_net(sk), net) ||
583 udp_sk(sk)->udp_port_hash != hnum ||
584 (inet->inet_daddr && inet->inet_daddr != rmt_addr) ||
585 (inet->inet_dport != rmt_port && inet->inet_dport) ||
586 (inet->inet_rcv_saddr && inet->inet_rcv_saddr != loc_addr) ||
587 ipv6_only_sock(sk) ||
82ba25c6 588 !udp_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif))
421b3885 589 return false;
60d9b031 590 if (!ip_mc_sf_allow(sk, loc_addr, rmt_addr, dif, sdif))
421b3885
SB		 591 return false;
592 return true;
593}
594
a36e185e
SB		 595DEFINE_STATIC_KEY_FALSE(udp_encap_needed_key);
596void udp_encap_enable(void)
597{
9c480601 598 static_branch_inc(&udp_encap_needed_key);
a36e185e
SB		 599}
600EXPORT_SYMBOL(udp_encap_enable);
601
a4a600dd
XL		 602void udp_encap_disable(void)
603{
604 static_branch_dec(&udp_encap_needed_key);
605}
606EXPORT_SYMBOL(udp_encap_disable);
607
e7cc0824
SB		 608/* Handler for tunnels with arbitrary destination ports: no socket lookup, go
609 * through error handlers in encapsulations looking for a match.
610 */
611static int __udp4_lib_err_encap_no_sk(struct sk_buff *skb, u32 info)
612{
613 int i;
614
615 for (i = 0; i < MAX_IPTUN_ENCAP_OPS; i++) {
616 int (*handler)(struct sk_buff *skb, u32 info);
92b95364 617 const struct ip_tunnel_encap_ops *encap;
e7cc0824 618
92b95364
PA		 619 encap = rcu_dereference(iptun_encaps[i]);
620 if (!encap)
e7cc0824 621 continue;
92b95364 622 handler = encap->err_handler;
e7cc0824
SB		 623 if (handler && !handler(skb, info))
624 return 0;
625 }
626
627 return -ENOENT;
628}
629
a36e185e
SB		 630/* Try to match ICMP errors to UDP tunnels by looking up a socket without
631 * reversing source and destination port: this will match tunnels that force the
632 * same destination port on both endpoints (e.g. VXLAN, GENEVE). Note that
633 * lwtunnels might actually break this assumption by being configured with
634 * different destination ports on endpoints, in this case we won't be able to
635 * trace ICMP messages back to them.
636 *
e7cc0824
SB		 637 * If this doesn't match any socket, probe tunnels with arbitrary destination
638 * ports (e.g. FoU, GUE): there, the receiving socket is useless, as the port
639 * we've sent packets to won't necessarily match the local destination port.
640 *
a36e185e
SB		 641 * Then ask the tunnel implementation to match the error against a valid
642 * association.
643 *
e7cc0824
SB		 644 * Return an error if we can't find a match, the socket if we need further
645 * processing, zero otherwise.
a36e185e
SB		 646 */
647static struct sock *__udp4_lib_err_encap(struct net *net,
648 const struct iphdr *iph,
649 struct udphdr *uh,
650 struct udp_table *udptable,
9bfce73c 651 struct sock *sk,
e7cc0824 652 struct sk_buff *skb, u32 info)
a36e185e 653{
9bfce73c 654 int (*lookup)(struct sock *sk, struct sk_buff *skb);
a36e185e 655 int network_offset, transport_offset;
9bfce73c 656 struct udp_sock *up;
a36e185e 657
a36e185e
SB		 658 network_offset = skb_network_offset(skb);
659 transport_offset = skb_transport_offset(skb);
660
661 /* Network header needs to point to the outer IPv4 header inside ICMP */
662 skb_reset_network_header(skb);
663
664 /* Transport header needs to point to the UDP header */
665 skb_set_transport_header(skb, iph->ihl << 2);
666
9bfce73c
VF		 667 if (sk) {
668 up = udp_sk(sk);
669
670 lookup = READ_ONCE(up->encap_err_lookup);
671 if (lookup && lookup(sk, skb))
672 sk = NULL;
673
674 goto out;
675 }
676
e7cc0824
SB		 677 sk = __udp4_lib_lookup(net, iph->daddr, uh->source,
678 iph->saddr, uh->dest, skb->dev->ifindex, 0,
679 udptable, NULL);
680 if (sk) {
9bfce73c 681 up = udp_sk(sk);
e7cc0824
SB		 682
683 lookup = READ_ONCE(up->encap_err_lookup);
684 if (!lookup || lookup(sk, skb))
685 sk = NULL;
686 }
687
9bfce73c 688out:
e7cc0824
SB		 689 if (!sk)
690 sk = ERR_PTR(__udp4_lib_err_encap_no_sk(skb, info));
a36e185e
SB		 691
692 skb_set_transport_header(skb, transport_offset);
693 skb_set_network_header(skb, network_offset);
694
695 return sk;
696}
697
db8dac20
DM		 698/*
699 * This routine is called by the ICMP module when it gets some
700 * sort of error condition. If err < 0 then the socket should
701 * be closed and the error returned to the user. If err > 0
702 * it's just the icmp type << 8 | icmp code.
703 * Header points to the ip header of the error packet. We move
704 * on past this. Then (as it used to claim before adjustment)
705 * header points to the first 8 bytes of the udp header. We need
706 * to find the appropriate port.
707 */
708
32bbd879 709int __udp4_lib_err(struct sk_buff *skb, u32 info, struct udp_table *udptable)
db8dac20
DM		 710{
711 struct inet_sock *inet;
b71d1d42 712 const struct iphdr *iph = (const struct iphdr *)skb->data;
c482c568 713 struct udphdr *uh = (struct udphdr *)(skb->data+(iph->ihl<<2));
db8dac20
DM		 714 const int type = icmp_hdr(skb)->type;
715 const int code = icmp_hdr(skb)->code;
a36e185e 716 bool tunnel = false;
db8dac20
DM		 717 struct sock *sk;
718 int harderr;
719 int err;
fd54d716 720 struct net *net = dev_net(skb->dev);
db8dac20 721
fd54d716 722 sk = __udp4_lib_lookup(net, iph->daddr, uh->dest,
f64bf6b8
MM		 723 iph->saddr, uh->source, skb->dev->ifindex,
724 inet_sdif(skb), udptable, NULL);
9bfce73c 725
d26796ae 726 if (!sk || udp_sk(sk)->encap_type) {
a36e185e 727 /* No socket for error: try tunnels before discarding */
e7cc0824 728 if (static_branch_unlikely(&udp_encap_needed_key)) {
9bfce73c 729 sk = __udp4_lib_err_encap(net, iph, uh, udptable, sk, skb,
e7cc0824
SB		 730 info);
731 if (!sk)
732 return 0;
9bfce73c
VF		 733 } else
734 sk = ERR_PTR(-ENOENT);
a36e185e 735
e7cc0824 736 if (IS_ERR(sk)) {
a36e185e 737 __ICMP_INC_STATS(net, ICMP_MIB_INERRORS);
e7cc0824 738 return PTR_ERR(sk);
a36e185e 739 }
e7cc0824 740
a36e185e 741 tunnel = true;
db8dac20
DM		 742 }
743
744 err = 0;
745 harderr = 0;
746 inet = inet_sk(sk);
747
748 switch (type) {
749 default:
750 case ICMP_TIME_EXCEEDED:
751 err = EHOSTUNREACH;
752 break;
753 case ICMP_SOURCE_QUENCH:
754 goto out;
755 case ICMP_PARAMETERPROB:
756 err = EPROTO;
757 harderr = 1;
758 break;
759 case ICMP_DEST_UNREACH:
760 if (code == ICMP_FRAG_NEEDED) { /* Path MTU discovery */
36393395 761 ipv4_sk_update_pmtu(skb, sk, info);
db8dac20
DM		 762 if (inet->pmtudisc != IP_PMTUDISC_DONT) {
763 err = EMSGSIZE;
764 harderr = 1;
765 break;
766 }
767 goto out;
768 }
769 err = EHOSTUNREACH;
770 if (code <= NR_ICMP_UNREACH) {
771 harderr = icmp_err_convert[code].fatal;
772 err = icmp_err_convert[code].errno;
773 }
774 break;
55be7a9c
DM		 775 case ICMP_REDIRECT:
776 ipv4_sk_redirect(skb, sk);
1a462d18 777 goto out;
db8dac20
DM		 778 }
779
780 /*
781 * RFC1122: OK. Passes ICMP errors back to application, as per
782 * 4.1.3.3.
783 */
a36e185e
SB		 784 if (tunnel) {
785 /* ...not for tunnels though: we don't have a sending socket */
786 goto out;
787 }
db8dac20
DM		 788 if (!inet->recverr) {
789 if (!harderr || sk->sk_state != TCP_ESTABLISHED)
790 goto out;
b1faf566 791 } else
c482c568 792 ip_icmp_error(sk, skb, err, uh->dest, info, (u8 *)(uh+1));
b1faf566 793
db8dac20 794 sk->sk_err = err;
e3ae2365 795 sk_error_report(sk);
db8dac20 796out:
32bbd879 797 return 0;
db8dac20
DM		 798}
799
32bbd879 800int udp_err(struct sk_buff *skb, u32 info)
db8dac20 801{
32bbd879 802 return __udp4_lib_err(skb, info, &udp_table);
db8dac20
DM		 803}
804
805/*
806 * Throw away all pending data and cancel the corking. Socket is locked.
807 */
36d926b9 808void udp_flush_pending_frames(struct sock *sk)
db8dac20
DM		 809{
810 struct udp_sock *up = udp_sk(sk);
811
812 if (up->pending) {
813 up->len = 0;
814 up->pending = 0;
815 ip_flush_pending_frames(sk);
816 }
817}
36d926b9 818EXPORT_SYMBOL(udp_flush_pending_frames);
db8dac20
DM		 819
820/**
f6b9664f 821 * udp4_hwcsum - handle outgoing HW checksumming
db8dac20
DM		 822 * @skb: sk_buff containing the filled-in UDP header
823 * (checksum field must be zeroed out)
f6b9664f
HX		 824 * @src: source IP address
825 * @dst: destination IP address
db8dac20 826 */
c26bf4a5 827void udp4_hwcsum(struct sk_buff *skb, __be32 src, __be32 dst)
db8dac20 828{
db8dac20 829 struct udphdr *uh = udp_hdr(skb);
f6b9664f
HX		 830 int offset = skb_transport_offset(skb);
831 int len = skb->len - offset;
832 int hlen = len;
db8dac20
DM		 833 __wsum csum = 0;
834
ebbe495f 835 if (!skb_has_frag_list(skb)) {
db8dac20
DM		 836 /*
837 * Only one fragment on the socket.
838 */
839 skb->csum_start = skb_transport_header(skb) - skb->head;
840 skb->csum_offset = offsetof(struct udphdr, check);
f6b9664f
HX		 841 uh->check = ~csum_tcpudp_magic(src, dst, len,
842 IPPROTO_UDP, 0);
db8dac20 843 } else {
ebbe495f
WC		 844 struct sk_buff *frags;
845
db8dac20
DM		 846 /*
847 * HW-checksum won't work as there are two or more
848 * fragments on the socket so that all csums of sk_buffs
849 * should be together
850 */
ebbe495f 851 skb_walk_frags(skb, frags) {
f6b9664f
HX		 852 csum = csum_add(csum, frags->csum);
853 hlen -= frags->len;
ebbe495f 854 }
db8dac20 855
f6b9664f 856 csum = skb_checksum(skb, offset, hlen, csum);
db8dac20
DM		 857 skb->ip_summed = CHECKSUM_NONE;
858
db8dac20
DM		 859 uh->check = csum_tcpudp_magic(src, dst, len, IPPROTO_UDP, csum);
860 if (uh->check == 0)
861 uh->check = CSUM_MANGLED_0;
862 }
863}
c26bf4a5 864EXPORT_SYMBOL_GPL(udp4_hwcsum);
db8dac20 865
af5fcba7
TH		 866/* Function to set UDP checksum for an IPv4 UDP packet. This is intended
867 * for the simple case like when setting the checksum for a UDP tunnel.
868 */
869void udp_set_csum(bool nocheck, struct sk_buff *skb,
870 __be32 saddr, __be32 daddr, int len)
871{
872 struct udphdr *uh = udp_hdr(skb);
873
179bc67f 874 if (nocheck) {
af5fcba7 875 uh->check = 0;
179bc67f 876 } else if (skb_is_gso(skb)) {
af5fcba7 877 uh->check = ~udp_v4_check(len, saddr, daddr, 0);
179bc67f
EC		 878 } else if (skb->ip_summed == CHECKSUM_PARTIAL) {
879 uh->check = 0;
880 uh->check = udp_v4_check(len, saddr, daddr, lco_csum(skb));
881 if (uh->check == 0)
882 uh->check = CSUM_MANGLED_0;
d75f1306 883 } else {
af5fcba7
TH		 884 skb->ip_summed = CHECKSUM_PARTIAL;
885 skb->csum_start = skb_transport_header(skb) - skb->head;
886 skb->csum_offset = offsetof(struct udphdr, check);
887 uh->check = ~udp_v4_check(len, saddr, daddr, 0);
af5fcba7
TH		 888 }
889}
890EXPORT_SYMBOL(udp_set_csum);
891
bec1f6f6
WB		 892static int udp_send_skb(struct sk_buff *skb, struct flowi4 *fl4,
893 struct inet_cork *cork)
db8dac20 894{
f6b9664f 895 struct sock *sk = skb->sk;
db8dac20 896 struct inet_sock *inet = inet_sk(sk);
db8dac20 897 struct udphdr *uh;
cffb8f61 898 int err;
db8dac20 899 int is_udplite = IS_UDPLITE(sk);
f6b9664f
HX		 900 int offset = skb_transport_offset(skb);
901 int len = skb->len - offset;
4094871d 902 int datalen = len - sizeof(*uh);
db8dac20
DM		 903 __wsum csum = 0;
904
db8dac20
DM		 905 /*
906 * Create a UDP header
907 */
908 uh = udp_hdr(skb);
f6b9664f 909 uh->source = inet->inet_sport;
79ab0531 910 uh->dest = fl4->fl4_dport;
f6b9664f 911 uh->len = htons(len);
db8dac20
DM		 912 uh->check = 0;
913
bec1f6f6
WB		 914 if (cork->gso_size) {
915 const int hlen = skb_network_header_len(skb) +
916 sizeof(struct udphdr);
917
0f149c9f
WB		 918 if (hlen + cork->gso_size > cork->fragsize) {
919 kfree_skb(skb);
bec1f6f6 920 return -EINVAL;
0f149c9f 921 }
158390e4 922 if (datalen > cork->gso_size * UDP_MAX_SEGMENTS) {
0f149c9f 923 kfree_skb(skb);
bec1f6f6 924 return -EINVAL;
0f149c9f
WB		 925 }
926 if (sk->sk_no_check_tx) {
927 kfree_skb(skb);
a8c744a8 928 return -EINVAL;
0f149c9f 929 }
ff06342c 930 if (skb->ip_summed != CHECKSUM_PARTIAL || is_udplite ||
0f149c9f
WB		 931 dst_xfrm(skb_dst(skb))) {
932 kfree_skb(skb);
bec1f6f6 933 return -EIO;
0f149c9f 934 }
bec1f6f6 935
4094871d
JH		 936 if (datalen > cork->gso_size) {
937 skb_shinfo(skb)->gso_size = cork->gso_size;
938 skb_shinfo(skb)->gso_type = SKB_GSO_UDP_L4;
939 skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(datalen,
940 cork->gso_size);
941 }
a8c744a8 942 goto csum_partial;
bec1f6f6
WB		 943 }
944
db8dac20 945 if (is_udplite) /* UDP-Lite */
f6b9664f 946 csum = udplite_csum(skb);
db8dac20 947
ab2fb7e3 948 else if (sk->sk_no_check_tx) { /* UDP csum off */
db8dac20
DM		 949
950 skb->ip_summed = CHECKSUM_NONE;
951 goto send;
952
953 } else if (skb->ip_summed == CHECKSUM_PARTIAL) { /* UDP hardware csum */
a8c744a8 954csum_partial:
db8dac20 955
79ab0531 956 udp4_hwcsum(skb, fl4->saddr, fl4->daddr);
db8dac20
DM		 957 goto send;
958
f6b9664f
HX		 959 } else
960 csum = udp_csum(skb);
db8dac20
DM		 961
962 /* add protocol-dependent pseudo-header */
79ab0531 963 uh->check = csum_tcpudp_magic(fl4->saddr, fl4->daddr, len,
c482c568 964 sk->sk_protocol, csum);
db8dac20
DM		 965 if (uh->check == 0)
966 uh->check = CSUM_MANGLED_0;
967
968send:
b5ec8eea 969 err = ip_send_skb(sock_net(sk), skb);
6ce9e7b5
ED		 970 if (err) {
971 if (err == -ENOBUFS && !inet->recverr) {
6aef70a8
ED		 972 UDP_INC_STATS(sock_net(sk),
973 UDP_MIB_SNDBUFERRORS, is_udplite);
6ce9e7b5
ED		 974 err = 0;
975 }
976 } else
6aef70a8
ED		 977 UDP_INC_STATS(sock_net(sk),
978 UDP_MIB_OUTDATAGRAMS, is_udplite);
f6b9664f
HX		 979 return err;
980}
981
982/*
983 * Push out all pending data as one UDP datagram. Socket is locked.
984 */
8822b64a 985int udp_push_pending_frames(struct sock *sk)
f6b9664f
HX		 986{
987 struct udp_sock *up = udp_sk(sk);
988 struct inet_sock *inet = inet_sk(sk);
b6f21b26 989 struct flowi4 *fl4 = &inet->cork.fl.u.ip4;
f6b9664f
HX		 990 struct sk_buff *skb;
991 int err = 0;
992
77968b78 993 skb = ip_finish_skb(sk, fl4);
f6b9664f
HX		 994 if (!skb)
995 goto out;
996
bec1f6f6 997 err = udp_send_skb(skb, fl4, &inet->cork.base);
f6b9664f 998
db8dac20
DM		 999out:
1000 up->len = 0;
1001 up->pending = 0;
db8dac20
DM		 1002 return err;
1003}
8822b64a 1004EXPORT_SYMBOL(udp_push_pending_frames);
db8dac20 1005
2e8de857
WB		 1006static int __udp_cmsg_send(struct cmsghdr *cmsg, u16 *gso_size)
1007{
1008 switch (cmsg->cmsg_type) {
1009 case UDP_SEGMENT:
1010 if (cmsg->cmsg_len != CMSG_LEN(sizeof(__u16)))
1011 return -EINVAL;
1012 *gso_size = *(__u16 *)CMSG_DATA(cmsg);
1013 return 0;
1014 default:
1015 return -EINVAL;
1016 }
1017}
1018
1019int udp_cmsg_send(struct sock *sk, struct msghdr *msg, u16 *gso_size)
1020{
1021 struct cmsghdr *cmsg;
1022 bool need_ip = false;
1023 int err;
1024
1025 for_each_cmsghdr(cmsg, msg) {
1026 if (!CMSG_OK(msg, cmsg))
1027 return -EINVAL;
1028
1029 if (cmsg->cmsg_level != SOL_UDP) {
1030 need_ip = true;
1031 continue;
1032 }
1033
1034 err = __udp_cmsg_send(cmsg, gso_size);
1035 if (err)
1036 return err;
1037 }
1038
1039 return need_ip;
1040}
1041EXPORT_SYMBOL_GPL(udp_cmsg_send);
1042
1b784140 1043int udp_sendmsg(struct sock *sk, struct msghdr *msg, size_t len)
db8dac20
DM		 1044{
1045 struct inet_sock *inet = inet_sk(sk);
1046 struct udp_sock *up = udp_sk(sk);
1cedee13 1047 DECLARE_SOCKADDR(struct sockaddr_in *, usin, msg->msg_name);
e474995f 1048 struct flowi4 fl4_stack;
b6f21b26 1049 struct flowi4 *fl4;
db8dac20
DM		 1050 int ulen = len;
1051 struct ipcm_cookie ipc;
1052 struct rtable *rt = NULL;
1053 int free = 0;
1054 int connected = 0;
1055 __be32 daddr, faddr, saddr;
1056 __be16 dport;
1057 u8 tos;
1058 int err, is_udplite = IS_UDPLITE(sk);
a9f59707 1059 int corkreq = READ_ONCE(up->corkflag) || msg->msg_flags&MSG_MORE;
db8dac20 1060 int (*getfrag)(void *, char *, int, int, int, struct sk_buff *);
903ab86d 1061 struct sk_buff *skb;
f6d8bd05 1062 struct ip_options_data opt_copy;
db8dac20
DM		 1063
1064 if (len > 0xFFFF)
1065 return -EMSGSIZE;
1066
1067 /*
1068 * Check the flags.
1069 */
1070
c482c568 1071 if (msg->msg_flags & MSG_OOB) /* Mirror BSD error message compatibility */
db8dac20
DM		 1072 return -EOPNOTSUPP;
1073
903ab86d
HX		 1074 getfrag = is_udplite ? udplite_getfrag : ip_generic_getfrag;
1075
f5fca608 1076 fl4 = &inet->cork.fl.u.ip4;
db8dac20
DM		 1077 if (up->pending) {
1078 /*
1079 * There are pending frames.
1080 * The socket lock must be held while it's corked.
1081 */
1082 lock_sock(sk);
1083 if (likely(up->pending)) {
1084 if (unlikely(up->pending != AF_INET)) {
1085 release_sock(sk);
1086 return -EINVAL;
1087 }
1088 goto do_append_data;
1089 }
1090 release_sock(sk);
1091 }
1092 ulen += sizeof(struct udphdr);
1093
1094 /*
1095 * Get and verify the address.
1096 */
1cedee13 1097 if (usin) {
db8dac20
DM		 1098 if (msg->msg_namelen < sizeof(*usin))
1099 return -EINVAL;
1100 if (usin->sin_family != AF_INET) {
1101 if (usin->sin_family != AF_UNSPEC)
1102 return -EAFNOSUPPORT;
1103 }
1104
1105 daddr = usin->sin_addr.s_addr;
1106 dport = usin->sin_port;
1107 if (dport == 0)
1108 return -EINVAL;
1109 } else {
1110 if (sk->sk_state != TCP_ESTABLISHED)
1111 return -EDESTADDRREQ;
c720c7e8
ED		 1112 daddr = inet->inet_daddr;
1113 dport = inet->inet_dport;
db8dac20
DM		 1114 /* Open fast path for connected socket.
1115 Route will not be used, if at least one option is set.
1116 */
1117 connected = 1;
1118 }
db8dac20 1119
35178206 1120 ipcm_init_sk(&ipc, inet);
18a419ba 1121 ipc.gso_size = READ_ONCE(up->gso_size);
bf84a010 1122
db8dac20 1123 if (msg->msg_controllen) {
2e8de857
WB		 1124 err = udp_cmsg_send(sk, msg, &ipc.gso_size);
1125 if (err > 0)
1126 err = ip_cmsg_send(sk, msg, &ipc,
1127 sk->sk_family == AF_INET6);
1128 if (unlikely(err < 0)) {
91948309 1129 kfree(ipc.opt);
db8dac20 1130 return err;
91948309 1131 }
db8dac20
DM		 1132 if (ipc.opt)
1133 free = 1;
1134 connected = 0;
1135 }
f6d8bd05
ED		 1136 if (!ipc.opt) {
1137 struct ip_options_rcu *inet_opt;
1138
1139 rcu_read_lock();
1140 inet_opt = rcu_dereference(inet->inet_opt);
1141 if (inet_opt) {
1142 memcpy(&opt_copy, inet_opt,
1143 sizeof(*inet_opt) + inet_opt->opt.optlen);
1144 ipc.opt = &opt_copy.opt;
1145 }
1146 rcu_read_unlock();
1147 }
db8dac20 1148
6fc88c35 1149 if (cgroup_bpf_enabled(CGROUP_UDP4_SENDMSG) && !connected) {
1cedee13
AI		 1150 err = BPF_CGROUP_RUN_PROG_UDP4_SENDMSG_LOCK(sk,
1151 (struct sockaddr *)usin, &ipc.addr);
1152 if (err)
1153 goto out_free;
1154 if (usin) {
1155 if (usin->sin_port == 0) {
1156 /* BPF program set invalid port. Reject it. */
1157 err = -EINVAL;
1158 goto out_free;
1159 }
1160 daddr = usin->sin_addr.s_addr;
1161 dport = usin->sin_port;
1162 }
1163 }
1164
db8dac20
DM		 1165 saddr = ipc.addr;
1166 ipc.addr = faddr = daddr;
1167
f6d8bd05 1168 if (ipc.opt && ipc.opt->opt.srr) {
1b97013b
AI		 1169 if (!daddr) {
1170 err = -EINVAL;
1171 goto out_free;
1172 }
f6d8bd05 1173 faddr = ipc.opt->opt.faddr;
db8dac20
DM		 1174 connected = 0;
1175 }
aa661581 1176 tos = get_rttos(&ipc, inet);
db8dac20
DM		 1177 if (sock_flag(sk, SOCK_LOCALROUTE) ||
1178 (msg->msg_flags & MSG_DONTROUTE) ||
f6d8bd05 1179 (ipc.opt && ipc.opt->opt.is_strictroute)) {
db8dac20
DM		 1180 tos |= RTO_ONLINK;
1181 connected = 0;
1182 }
1183
1184 if (ipv4_is_multicast(daddr)) {
854da991 1185 if (!ipc.oif || netif_index_is_l3_master(sock_net(sk), ipc.oif))
db8dac20
DM		 1186 ipc.oif = inet->mc_index;
1187 if (!saddr)
1188 saddr = inet->mc_addr;
1189 connected = 0;
9515a2e0 1190 } else if (!ipc.oif) {
76e21053 1191 ipc.oif = inet->uc_index;
9515a2e0
DA		 1192 } else if (ipv4_is_lbcast(daddr) && inet->uc_index) {
1193 /* oif is set, packet is to local broadcast and
2bdcc73c 1194 * uc_index is set. oif is most likely set
9515a2e0
DA		 1195 * by sk_bound_dev_if. If uc_index != oif check if the
1196 * oif is an L3 master and uc_index is an L3 slave.
1197 * If so, we want to allow the send using the uc_index.
1198 */
1199 if (ipc.oif != inet->uc_index &&
1200 ipc.oif == l3mdev_master_ifindex_by_index(sock_net(sk),
1201 inet->uc_index)) {
1202 ipc.oif = inet->uc_index;
1203 }
1204 }
db8dac20
DM		 1205
1206 if (connected)
c482c568 1207 rt = (struct rtable *)sk_dst_check(sk, 0);
db8dac20 1208
51456b29 1209 if (!rt) {
84a3aa00 1210 struct net *net = sock_net(sk);
9a24abfa 1211 __u8 flow_flags = inet_sk_flowi_flags(sk);
84a3aa00 1212
e474995f 1213 fl4 = &fl4_stack;
9a24abfa 1214
c6af0c22 1215 flowi4_init_output(fl4, ipc.oif, ipc.sockc.mark, tos,
c0951cbc 1216 RT_SCOPE_UNIVERSE, sk->sk_protocol,
9a24abfa 1217 flow_flags,
e2d118a1
LC		 1218 faddr, saddr, dport, inet->inet_sport,
1219 sk->sk_uid);
c0951cbc 1220
3df98d79 1221 security_sk_classify_flow(sk, flowi4_to_flowi_common(fl4));
e474995f 1222 rt = ip_route_output_flow(net, fl4, sk);
b23dd4fe
DM		 1223 if (IS_ERR(rt)) {
1224 err = PTR_ERR(rt);
06dc94b1 1225 rt = NULL;
db8dac20 1226 if (err == -ENETUNREACH)
f1d8cba6 1227 IP_INC_STATS(net, IPSTATS_MIB_OUTNOROUTES);
db8dac20
DM		 1228 goto out;
1229 }
1230
1231 err = -EACCES;
1232 if ((rt->rt_flags & RTCF_BROADCAST) &&
1233 !sock_flag(sk, SOCK_BROADCAST))
1234 goto out;
1235 if (connected)
d8d1f30b 1236 sk_dst_set(sk, dst_clone(&rt->dst));
db8dac20
DM		 1237 }
1238
1239 if (msg->msg_flags&MSG_CONFIRM)
1240 goto do_confirm;
1241back_from_confirm:
1242
e474995f 1243 saddr = fl4->saddr;
db8dac20 1244 if (!ipc.addr)
e474995f 1245 daddr = ipc.addr = fl4->daddr;
db8dac20 1246
903ab86d
HX		 1247 /* Lockless fast path for the non-corking case. */
1248 if (!corkreq) {
1cd7884d
WB		 1249 struct inet_cork cork;
1250
f69e6d13 1251 skb = ip_make_skb(sk, fl4, getfrag, msg, ulen,
903ab86d 1252 sizeof(struct udphdr), &ipc, &rt,
1cd7884d 1253 &cork, msg->msg_flags);
903ab86d 1254 err = PTR_ERR(skb);
50c3a487 1255 if (!IS_ERR_OR_NULL(skb))
bec1f6f6 1256 err = udp_send_skb(skb, fl4, &cork);
903ab86d
HX		 1257 goto out;
1258 }
1259
db8dac20
DM		 1260 lock_sock(sk);
1261 if (unlikely(up->pending)) {
1262 /* The socket is already corked while preparing it. */
1263 /* ... which is an evident application bug. --ANK */
1264 release_sock(sk);
1265
197df02c 1266 net_dbg_ratelimited("socket already corked\n");
db8dac20
DM		 1267 err = -EINVAL;
1268 goto out;
1269 }
1270 /*
1271 * Now cork the socket to pend data.
1272 */
b6f21b26
DM		 1273 fl4 = &inet->cork.fl.u.ip4;
1274 fl4->daddr = daddr;
1275 fl4->saddr = saddr;
9cce96df
DM		 1276 fl4->fl4_dport = dport;
1277 fl4->fl4_sport = inet->inet_sport;
db8dac20
DM		 1278 up->pending = AF_INET;
1279
1280do_append_data:
1281 up->len += ulen;
f69e6d13 1282 err = ip_append_data(sk, fl4, getfrag, msg, ulen,
f5fca608
DM		 1283 sizeof(struct udphdr), &ipc, &rt,
1284 corkreq ? msg->msg_flags|MSG_MORE : msg->msg_flags);
db8dac20
DM		 1285 if (err)
1286 udp_flush_pending_frames(sk);
1287 else if (!corkreq)
1288 err = udp_push_pending_frames(sk);
1289 else if (unlikely(skb_queue_empty(&sk->sk_write_queue)))
1290 up->pending = 0;
1291 release_sock(sk);
1292
1293out:
1294 ip_rt_put(rt);
1b97013b 1295out_free:
db8dac20
DM		 1296 if (free)
1297 kfree(ipc.opt);
1298 if (!err)
1299 return len;
1300 /*
1301 * ENOBUFS = no kernel mem, SOCK_NOSPACE = no sndbuf space. Reporting
1302 * ENOBUFS might not be good (it's not tunable per se), but otherwise
1303 * we don't have a good statistic (IpOutDiscards but it can be too many
1304 * things). We could add another new stat but at least for now that
1305 * seems like overkill.
1306 */
1307 if (err == -ENOBUFS || test_bit(SOCK_NOSPACE, &sk->sk_socket->flags)) {
6aef70a8
ED		 1308 UDP_INC_STATS(sock_net(sk),
1309 UDP_MIB_SNDBUFERRORS, is_udplite);
db8dac20
DM		 1310 }
1311 return err;
1312
1313do_confirm:
0dec879f
JA		 1314 if (msg->msg_flags & MSG_PROBE)
1315 dst_confirm_neigh(&rt->dst, &fl4->daddr);
db8dac20
DM		 1316 if (!(msg->msg_flags&MSG_PROBE) || len)
1317 goto back_from_confirm;
1318 err = 0;
1319 goto out;
1320}
c482c568 1321EXPORT_SYMBOL(udp_sendmsg);
db8dac20
DM		 1322
1323int udp_sendpage(struct sock *sk, struct page *page, int offset,
1324 size_t size, int flags)
1325{
f5fca608 1326 struct inet_sock *inet = inet_sk(sk);
db8dac20
DM		 1327 struct udp_sock *up = udp_sk(sk);
1328 int ret;
1329
d3f7d56a
SL		 1330 if (flags & MSG_SENDPAGE_NOTLAST)
1331 flags |= MSG_MORE;
1332
db8dac20
DM		 1333 if (!up->pending) {
1334 struct msghdr msg = { .msg_flags = flags|MSG_MORE };
1335
1336 /* Call udp_sendmsg to specify destination address which
1337 * sendpage interface can't pass.
1338 * This will succeed only when the socket is connected.
1339 */
1b784140 1340 ret = udp_sendmsg(sk, &msg, 0);
db8dac20
DM		 1341 if (ret < 0)
1342 return ret;
1343 }
1344
1345 lock_sock(sk);
1346
1347 if (unlikely(!up->pending)) {
1348 release_sock(sk);
1349
197df02c 1350 net_dbg_ratelimited("cork failed\n");
db8dac20
DM		 1351 return -EINVAL;
1352 }
1353
f5fca608
DM		 1354 ret = ip_append_page(sk, &inet->cork.fl.u.ip4,
1355 page, offset, size, flags);
db8dac20
DM		 1356 if (ret == -EOPNOTSUPP) {
1357 release_sock(sk);
1358 return sock_no_sendpage(sk->sk_socket, page, offset,
1359 size, flags);
1360 }
1361 if (ret < 0) {
1362 udp_flush_pending_frames(sk);
1363 goto out;
1364 }
1365
1366 up->len += size;
a9f59707 1367 if (!(READ_ONCE(up->corkflag) || (flags&MSG_MORE)))
db8dac20
DM		 1368 ret = udp_push_pending_frames(sk);
1369 if (!ret)
1370 ret = size;
1371out:
1372 release_sock(sk);
1373 return ret;
1374}
1375
dce4551c
PA		 1376#define UDP_SKB_IS_STATELESS 0x80000000
1377
677bf08c
FW		 1378/* all head states (dst, sk, nf conntrack) except skb extensions are
1379 * cleared by udp_rcv().
1380 *
1381 * We need to preserve secpath, if present, to eventually process
1382 * IP_CMSG_PASSSEC at recvmsg() time.
1383 *
1384 * Other extensions can be cleared.
1385 */
1386static bool udp_try_make_stateless(struct sk_buff *skb)
1387{
1388 if (!skb_has_extensions(skb))
1389 return true;
1390
1391 if (!secpath_exists(skb)) {
1392 skb_ext_reset(skb);
1393 return true;
1394 }
1395
1396 return false;
1397}
1398
b65ac446
PA		 1399static void udp_set_dev_scratch(struct sk_buff *skb)
1400{
dce4551c 1401 struct udp_dev_scratch *scratch = udp_skb_scratch(skb);
b65ac446
PA		 1402
1403 BUILD_BUG_ON(sizeof(struct udp_dev_scratch) > sizeof(long));
dce4551c
PA		 1404 scratch->_tsize_state = skb->truesize;
1405#if BITS_PER_LONG == 64
b65ac446
PA		 1406 scratch->len = skb->len;
1407 scratch->csum_unnecessary = !!skb_csum_unnecessary(skb);
1408 scratch->is_linear = !skb_is_nonlinear(skb);
dce4551c 1409#endif
677bf08c 1410 if (udp_try_make_stateless(skb))
dce4551c 1411 scratch->_tsize_state |= UDP_SKB_IS_STATELESS;
b65ac446
PA		 1412}
1413
a793183c
ED		 1414static void udp_skb_csum_unnecessary_set(struct sk_buff *skb)
1415{
1416 /* We come here after udp_lib_checksum_complete() returned 0.
1417 * This means that __skb_checksum_complete() might have
1418 * set skb->csum_valid to 1.
1419 * On 64bit platforms, we can set csum_unnecessary
1420 * to true, but only if the skb is not shared.
1421 */
1422#if BITS_PER_LONG == 64
1423 if (!skb_shared(skb))
1424 udp_skb_scratch(skb)->csum_unnecessary = true;
1425#endif
1426}
1427
b65ac446
PA		 1428static int udp_skb_truesize(struct sk_buff *skb)
1429{
dce4551c 1430 return udp_skb_scratch(skb)->_tsize_state & ~UDP_SKB_IS_STATELESS;
b65ac446
PA		 1431}
1432
dce4551c 1433static bool udp_skb_has_head_state(struct sk_buff *skb)
b65ac446 1434{
dce4551c 1435 return !(udp_skb_scratch(skb)->_tsize_state & UDP_SKB_IS_STATELESS);
b65ac446 1436}
b65ac446 1437
7c13f97f 1438/* fully reclaim rmem/fwd memory allocated for skb */
6dfb4367
PA		 1439static void udp_rmem_release(struct sock *sk, int size, int partial,
1440 bool rx_queue_lock_held)
f970bd9e 1441{
6b229cf7 1442 struct udp_sock *up = udp_sk(sk);
2276f58a 1443 struct sk_buff_head *sk_queue;
f970bd9e
PA		 1444 int amt;
1445
6b229cf7
ED		 1446 if (likely(partial)) {
1447 up->forward_deficit += size;
1448 size = up->forward_deficit;
d39ca259
PA		 1449 if (size < (sk->sk_rcvbuf >> 2) &&
1450 !skb_queue_empty(&up->reader_queue))
6b229cf7
ED		 1451 return;
1452 } else {
1453 size += up->forward_deficit;
1454 }
1455 up->forward_deficit = 0;
1456
6dfb4367
PA		 1457 /* acquire the sk_receive_queue for fwd allocated memory scheduling,
1458 * if the called don't held it already
1459 */
2276f58a 1460 sk_queue = &sk->sk_receive_queue;
6dfb4367
PA		 1461 if (!rx_queue_lock_held)
1462 spin_lock(&sk_queue->lock);
1463
2276f58a 1464
f970bd9e 1465 sk->sk_forward_alloc += size;
100fdd1f 1466 amt = (sk->sk_forward_alloc - partial) & ~(PAGE_SIZE - 1);
f970bd9e 1467 sk->sk_forward_alloc -= amt;
f970bd9e
PA		 1468
1469 if (amt)
100fdd1f 1470 __sk_mem_reduce_allocated(sk, amt >> PAGE_SHIFT);
02ab0d13
ED		 1471
1472 atomic_sub(size, &sk->sk_rmem_alloc);
2276f58a
PA		 1473
1474 /* this can save us from acquiring the rx queue lock on next receive */
1475 skb_queue_splice_tail_init(sk_queue, &up->reader_queue);
1476
6dfb4367
PA		 1477 if (!rx_queue_lock_held)
1478 spin_unlock(&sk_queue->lock);
f970bd9e
PA		 1479}
1480
2276f58a 1481/* Note: called with reader_queue.lock held.
c84d9490
ED		 1482 * Instead of using skb->truesize here, find a copy of it in skb->dev_scratch
1483 * This avoids a cache line miss while receive_queue lock is held.
1484 * Look at __udp_enqueue_schedule_skb() to find where this copy is done.
1485 */
7c13f97f 1486void udp_skb_destructor(struct sock *sk, struct sk_buff *skb)
f970bd9e 1487{
b65ac446
PA		 1488 prefetch(&skb->data);
1489 udp_rmem_release(sk, udp_skb_truesize(skb), 1, false);
f970bd9e 1490}
7c13f97f 1491EXPORT_SYMBOL(udp_skb_destructor);
f970bd9e 1492
6dfb4367 1493/* as above, but the caller held the rx queue lock, too */
64f5102d 1494static void udp_skb_dtor_locked(struct sock *sk, struct sk_buff *skb)
6dfb4367 1495{
b65ac446
PA		 1496 prefetch(&skb->data);
1497 udp_rmem_release(sk, udp_skb_truesize(skb), 1, true);
6dfb4367
PA		 1498}
1499
4b272750
ED		 1500/* Idea of busylocks is to let producers grab an extra spinlock
1501 * to relieve pressure on the receive_queue spinlock shared by consumer.
1502 * Under flood, this means that only one producer can be in line
1503 * trying to acquire the receive_queue spinlock.
1504 * These busylock can be allocated on a per cpu manner, instead of a
1505 * per socket one (that would consume a cache line per socket)
1506 */
1507static int udp_busylocks_log __read_mostly;
1508static spinlock_t *udp_busylocks __read_mostly;
1509
1510static spinlock_t *busylock_acquire(void *ptr)
1511{
1512 spinlock_t *busy;
1513
1514 busy = udp_busylocks + hash_ptr(ptr, udp_busylocks_log);
1515 spin_lock(busy);
1516 return busy;
1517}
1518
1519static void busylock_release(spinlock_t *busy)
1520{
1521 if (busy)
1522 spin_unlock(busy);
1523}
1524
f970bd9e
PA		 1525int __udp_enqueue_schedule_skb(struct sock *sk, struct sk_buff *skb)
1526{
1527 struct sk_buff_head *list = &sk->sk_receive_queue;
1528 int rmem, delta, amt, err = -ENOMEM;
4b272750 1529 spinlock_t *busy = NULL;
c8c8b127 1530 int size;
f970bd9e
PA		 1531
1532 /* try to avoid the costly atomic add/sub pair when the receive
1533 * queue is full; always allow at least a packet
1534 */
1535 rmem = atomic_read(&sk->sk_rmem_alloc);
363dc73a 1536 if (rmem > sk->sk_rcvbuf)
f970bd9e
PA		 1537 goto drop;
1538
c8c8b127
ED		 1539 /* Under mem pressure, it might be helpful to help udp_recvmsg()
1540 * having linear skbs :
1541 * - Reduce memory overhead and thus increase receive queue capacity
1542 * - Less cache line misses at copyout() time
1543 * - Less work at consume_skb() (less alien page frag freeing)
1544 */
4b272750 1545 if (rmem > (sk->sk_rcvbuf >> 1)) {
c8c8b127 1546 skb_condense(skb);
4b272750
ED		 1547
1548 busy = busylock_acquire(sk);
1549 }
c8c8b127 1550 size = skb->truesize;
b65ac446 1551 udp_set_dev_scratch(skb);
c8c8b127 1552
f970bd9e
PA		 1553 /* we drop only if the receive buf is full and the receive
1554 * queue contains some other skb
1555 */
1556 rmem = atomic_add_return(size, &sk->sk_rmem_alloc);
feed8a4f 1557 if (rmem > (size + (unsigned int)sk->sk_rcvbuf))
f970bd9e
PA		 1558 goto uncharge_drop;
1559
1560 spin_lock(&list->lock);
1561 if (size >= sk->sk_forward_alloc) {
1562 amt = sk_mem_pages(size);
100fdd1f 1563 delta = amt << PAGE_SHIFT;
f970bd9e
PA		 1564 if (!__sk_mem_raise_allocated(sk, delta, amt, SK_MEM_RECV)) {
1565 err = -ENOBUFS;
1566 spin_unlock(&list->lock);
1567 goto uncharge_drop;
1568 }
1569
1570 sk->sk_forward_alloc += delta;
1571 }
1572
1573 sk->sk_forward_alloc -= size;
1574
7c13f97f
PA		 1575 /* no need to setup a destructor, we will explicitly release the
1576 * forward allocated memory on dequeue
1577 */
f970bd9e
PA		 1578 sock_skb_set_dropcount(sk, skb);
1579
1580 __skb_queue_tail(list, skb);
1581 spin_unlock(&list->lock);
1582
1583 if (!sock_flag(sk, SOCK_DEAD))
1584 sk->sk_data_ready(sk);
1585
4b272750 1586 busylock_release(busy);
f970bd9e
PA		 1587 return 0;
1588
1589uncharge_drop:
1590 atomic_sub(skb->truesize, &sk->sk_rmem_alloc);
1591
1592drop:
1593 atomic_inc(&sk->sk_drops);
4b272750 1594 busylock_release(busy);
f970bd9e
PA		 1595 return err;
1596}
1597EXPORT_SYMBOL_GPL(__udp_enqueue_schedule_skb);
1598
c915fe13 1599void udp_destruct_sock(struct sock *sk)
f970bd9e
PA		 1600{
1601 /* reclaim completely the forward allocated memory */
2276f58a 1602 struct udp_sock *up = udp_sk(sk);
7c13f97f
PA		 1603 unsigned int total = 0;
1604 struct sk_buff *skb;
1605
2276f58a
PA		 1606 skb_queue_splice_tail_init(&sk->sk_receive_queue, &up->reader_queue);
1607 while ((skb = __skb_dequeue(&up->reader_queue)) != NULL) {
7c13f97f
PA		 1608 total += skb->truesize;
1609 kfree_skb(skb);
1610 }
6dfb4367 1611 udp_rmem_release(sk, total, 0, true);
7c13f97f 1612
f970bd9e
PA		 1613 inet_sock_destruct(sk);
1614}
c915fe13 1615EXPORT_SYMBOL_GPL(udp_destruct_sock);
f970bd9e
PA		 1616
1617int udp_init_sock(struct sock *sk)
1618{
2276f58a 1619 skb_queue_head_init(&udp_sk(sk)->reader_queue);
f970bd9e
PA		 1620 sk->sk_destruct = udp_destruct_sock;
1621 return 0;
1622}
1623EXPORT_SYMBOL_GPL(udp_init_sock);
1624
1625void skb_consume_udp(struct sock *sk, struct sk_buff *skb, int len)
1626{
1627 if (unlikely(READ_ONCE(sk->sk_peek_off) >= 0)) {
1628 bool slow = lock_sock_fast(sk);
1629
1630 sk_peek_offset_bwd(sk, len);
1631 unlock_sock_fast(sk, slow);
1632 }
0a463c78 1633
ca2c1418
PA		 1634 if (!skb_unref(skb))
1635 return;
1636
dce4551c
PA		 1637 /* In the more common cases we cleared the head states previously,
1638 * see __udp_queue_rcv_skb().
0ddf3fb2 1639 */
dce4551c 1640 if (unlikely(udp_skb_has_head_state(skb)))
0ddf3fb2 1641 skb_release_head_state(skb);
ca2c1418 1642 __consume_stateless_skb(skb);
f970bd9e
PA		 1643}
1644EXPORT_SYMBOL_GPL(skb_consume_udp);
1645
2276f58a
PA		 1646static struct sk_buff *__first_packet_length(struct sock *sk,
1647 struct sk_buff_head *rcvq,
1648 int *total)
1649{
1650 struct sk_buff *skb;
1651
9bd780f5
PA		 1652 while ((skb = skb_peek(rcvq)) != NULL) {
1653 if (udp_lib_checksum_complete(skb)) {
1654 __UDP_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS,
1655 IS_UDPLITE(sk));
1656 __UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS,
1657 IS_UDPLITE(sk));
1658 atomic_inc(&sk->sk_drops);
1659 __skb_unlink(skb, rcvq);
1660 *total += skb->truesize;
1661 kfree_skb(skb);
1662 } else {
a793183c 1663 udp_skb_csum_unnecessary_set(skb);
9bd780f5
PA		 1664 break;
1665 }
2276f58a
PA		 1666 }
1667 return skb;
1668}
1669
85584672
ED		 1670/**
1671 * first_packet_length - return length of first packet in receive queue
1672 * @sk: socket
1673 *
1674 * Drops all bad checksum frames, until a valid one is found.
e83c6744 1675 * Returns the length of found skb, or -1 if none is found.
85584672 1676 */
e83c6744 1677static int first_packet_length(struct sock *sk)
85584672 1678{
2276f58a
PA		 1679 struct sk_buff_head *rcvq = &udp_sk(sk)->reader_queue;
1680 struct sk_buff_head *sk_queue = &sk->sk_receive_queue;
85584672 1681 struct sk_buff *skb;
7c13f97f 1682 int total = 0;
e83c6744 1683 int res;
85584672 1684
85584672 1685 spin_lock_bh(&rcvq->lock);
2276f58a 1686 skb = __first_packet_length(sk, rcvq, &total);
137a0dbe 1687 if (!skb && !skb_queue_empty_lockless(sk_queue)) {
2276f58a
PA		 1688 spin_lock(&sk_queue->lock);
1689 skb_queue_splice_tail_init(sk_queue, rcvq);
1690 spin_unlock(&sk_queue->lock);
1691
1692 skb = __first_packet_length(sk, rcvq, &total);
85584672 1693 }
e83c6744 1694 res = skb ? skb->len : -1;
7c13f97f 1695 if (total)
6dfb4367 1696 udp_rmem_release(sk, total, 1, false);
85584672 1697 spin_unlock_bh(&rcvq->lock);
85584672
ED		 1698 return res;
1699}
1700
1da177e4
LT		 1701/*
1702 * IOCTL requests applicable to the UDP protocol
1703 */
e905a9ed 1704
1da177e4
LT		 1705int udp_ioctl(struct sock *sk, int cmd, unsigned long arg)
1706{
6516c655
SH		 1707 switch (cmd) {
1708 case SIOCOUTQ:
1da177e4 1709 {
31e6d363
ED		 1710 int amount = sk_wmem_alloc_get(sk);
1711
6516c655
SH		 1712 return put_user(amount, (int __user *)arg);
1713 }
1da177e4 1714
6516c655
SH		 1715 case SIOCINQ:
1716 {
e83c6744 1717 int amount = max_t(int, 0, first_packet_length(sk));
6516c655 1718
6516c655
SH		 1719 return put_user(amount, (int __user *)arg);
1720 }
1da177e4 1721
6516c655
SH		 1722 default:
1723 return -ENOIOCTLCMD;
1da177e4 1724 }
6516c655
SH		 1725
1726 return 0;
1da177e4 1727}
c482c568 1728EXPORT_SYMBOL(udp_ioctl);
1da177e4 1729
2276f58a 1730struct sk_buff *__skb_recv_udp(struct sock *sk, unsigned int flags,
ec095263 1731 int *off, int *err)
2276f58a
PA		 1732{
1733 struct sk_buff_head *sk_queue = &sk->sk_receive_queue;
1734 struct sk_buff_head *queue;
1735 struct sk_buff *last;
1736 long timeo;
1737 int error;
1738
1739 queue = &udp_sk(sk)->reader_queue;
2276f58a
PA		 1740 timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
1741 do {
1742 struct sk_buff *skb;
1743
1744 error = sock_error(sk);
1745 if (error)
1746 break;
1747
1748 error = -EAGAIN;
2276f58a 1749 do {
2276f58a 1750 spin_lock_bh(&queue->lock);
e427cad6
PA		 1751 skb = __skb_try_recv_from_queue(sk, queue, flags, off,
1752 err, &last);
2276f58a 1753 if (skb) {
e427cad6
PA		 1754 if (!(flags & MSG_PEEK))
1755 udp_skb_destructor(sk, skb);
2276f58a 1756 spin_unlock_bh(&queue->lock);
2276f58a
PA		 1757 return skb;
1758 }
1759
137a0dbe 1760 if (skb_queue_empty_lockless(sk_queue)) {
2276f58a
PA		 1761 spin_unlock_bh(&queue->lock);
1762 goto busy_check;
1763 }
1764
6dfb4367
PA		 1765 /* refill the reader queue and walk it again
1766 * keep both queues locked to avoid re-acquiring
1767 * the sk_receive_queue lock if fwd memory scheduling
1768 * is needed.
1769 */
2276f58a
PA		 1770 spin_lock(&sk_queue->lock);
1771 skb_queue_splice_tail_init(sk_queue, queue);
2276f58a 1772
e427cad6
PA		 1773 skb = __skb_try_recv_from_queue(sk, queue, flags, off,
1774 err, &last);
1775 if (skb && !(flags & MSG_PEEK))
1776 udp_skb_dtor_locked(sk, skb);
6dfb4367 1777 spin_unlock(&sk_queue->lock);
2276f58a 1778 spin_unlock_bh(&queue->lock);
de321ed3 1779 if (skb)
2276f58a 1780 return skb;
2276f58a
PA		 1781
1782busy_check:
1783 if (!sk_can_busy_loop(sk))
1784 break;
1785
1786 sk_busy_loop(sk, flags & MSG_DONTWAIT);
137a0dbe 1787 } while (!skb_queue_empty_lockless(sk_queue));
2276f58a
PA		 1788
1789 /* sk_queue is empty, reader_queue may contain peeked packets */
1790 } while (timeo &&
b50b0580
SD		 1791 !__skb_wait_for_more_packets(sk, &sk->sk_receive_queue,
1792 &error, &timeo,
2276f58a
PA		 1793 (struct sk_buff *)sk_queue));
1794
1795 *err = error;
1796 return NULL;
1797}
7e823644 1798EXPORT_SYMBOL(__skb_recv_udp);
2276f58a 1799
d7f57118
CW		 1800int udp_read_sock(struct sock *sk, read_descriptor_t *desc,
1801 sk_read_actor_t recv_actor)
1802{
1803 int copied = 0;
1804
1805 while (1) {
1806 struct sk_buff *skb;
1807 int err, used;
1808
ec095263 1809 skb = skb_recv_udp(sk, MSG_DONTWAIT, &err);
d7f57118
CW		 1810 if (!skb)
1811 return err;
099f896f
CW		 1812
1813 if (udp_lib_checksum_complete(skb)) {
1814 __UDP_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS,
1815 IS_UDPLITE(sk));
1816 __UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS,
1817 IS_UDPLITE(sk));
1818 atomic_inc(&sk->sk_drops);
1819 kfree_skb(skb);
1820 continue;
1821 }
1822
d7f57118
CW		 1823 used = recv_actor(desc, skb, 0, skb->len);
1824 if (used <= 0) {
1825 if (!copied)
1826 copied = used;
e00a5c33 1827 kfree_skb(skb);
d7f57118
CW		 1828 break;
1829 } else if (used <= skb->len) {
1830 copied += used;
1831 }
1832
e00a5c33 1833 kfree_skb(skb);
d7f57118
CW		 1834 if (!desc->count)
1835 break;
1836 }
1837
1838 return copied;
1839}
1840EXPORT_SYMBOL(udp_read_sock);
1841
db8dac20
DM		 1842/*
1843 * This should be easy, if there is something there we
1844 * return it, otherwise we block.
1845 */
1846
ec095263
OH		 1847int udp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int flags,
1848 int *addr_len)
db8dac20
DM		 1849{
1850 struct inet_sock *inet = inet_sk(sk);
342dfc30 1851 DECLARE_SOCKADDR(struct sockaddr_in *, sin, msg->msg_name);
db8dac20 1852 struct sk_buff *skb;
59c2cdae 1853 unsigned int ulen, copied;
fd69c399 1854 int off, err, peeking = flags & MSG_PEEK;
db8dac20 1855 int is_udplite = IS_UDPLITE(sk);
197c949e 1856 bool checksum_valid = false;
db8dac20 1857
db8dac20 1858 if (flags & MSG_ERRQUEUE)
85fbaa75 1859 return ip_recv_error(sk, msg, len, addr_len);
db8dac20
DM		 1860
1861try_again:
a0917e0b 1862 off = sk_peek_offset(sk, flags);
ec095263 1863 skb = __skb_recv_udp(sk, flags, &off, &err);
db8dac20 1864 if (!skb)
627d2d6b 1865 return err;
db8dac20 1866
b65ac446 1867 ulen = udp_skb_len(skb);
59c2cdae 1868 copied = len;
627d2d6b 1869 if (copied > ulen - off)
1870 copied = ulen - off;
59c2cdae 1871 else if (copied < ulen)
db8dac20
DM		 1872 msg->msg_flags |= MSG_TRUNC;
1873
1874 /*
1875 * If checksum is needed at all, try to do it while copying the
1876 * data. If the data is truncated, or if we only want a partial
1877 * coverage checksum (UDP-Lite), do it before the copy.
1878 */
1879
d21dbdfe
ED		 1880 if (copied < ulen || peeking ||
1881 (is_udplite && UDP_SKB_CB(skb)->partial_cov)) {
b65ac446
PA		 1882 checksum_valid = udp_skb_csum_unnecessary(skb) ||
1883 !__udp_lib_checksum_complete(skb);
197c949e 1884 if (!checksum_valid)
db8dac20
DM		 1885 goto csum_copy_err;
1886 }
1887
b65ac446
PA		 1888 if (checksum_valid || udp_skb_csum_unnecessary(skb)) {
1889 if (udp_skb_is_linear(skb))
1890 err = copy_linear_skb(skb, copied, off, &msg->msg_iter);
1891 else
1892 err = skb_copy_datagram_msg(skb, off, msg, copied);
1893 } else {
627d2d6b 1894 err = skb_copy_and_csum_datagram_msg(skb, off, msg);
db8dac20
DM		 1895
1896 if (err == -EINVAL)
1897 goto csum_copy_err;
1898 }
1899
22911fc5 1900 if (unlikely(err)) {
fd69c399 1901 if (!peeking) {
979402b1 1902 atomic_inc(&sk->sk_drops);
6aef70a8
ED		 1903 UDP_INC_STATS(sock_net(sk),
1904 UDP_MIB_INERRORS, is_udplite);
979402b1 1905 }
850cbadd 1906 kfree_skb(skb);
627d2d6b 1907 return err;
22911fc5 1908 }
db8dac20 1909
fd69c399 1910 if (!peeking)
6aef70a8
ED		 1911 UDP_INC_STATS(sock_net(sk),
1912 UDP_MIB_INDATAGRAMS, is_udplite);
db8dac20 1913
6fd1d51c 1914 sock_recv_cmsgs(msg, sk, skb);
db8dac20
DM		 1915
1916 /* Copy the address. */
c482c568 1917 if (sin) {
db8dac20
DM		 1918 sin->sin_family = AF_INET;
1919 sin->sin_port = udp_hdr(skb)->source;
1920 sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
1921 memset(sin->sin_zero, 0, sizeof(sin->sin_zero));
bceaa902 1922 *addr_len = sizeof(*sin);
983695fa 1923
a9ed15da
SF		 1924 BPF_CGROUP_RUN_PROG_UDP4_RECVMSG_LOCK(sk,
1925 (struct sockaddr *)sin);
db8dac20 1926 }
bcd1665e
PA		 1927
1928 if (udp_sk(sk)->gro_enabled)
1929 udp_cmsg_recv(msg, sk, skb);
1930
db8dac20 1931 if (inet->cmsg_flags)
ad959036 1932 ip_cmsg_recv_offset(msg, sk, skb, sizeof(struct udphdr), off);
db8dac20 1933
59c2cdae 1934 err = copied;
db8dac20
DM		 1935 if (flags & MSG_TRUNC)
1936 err = ulen;
1937
850cbadd 1938 skb_consume_udp(sk, skb, peeking ? -err : err);
db8dac20
DM		 1939 return err;
1940
1941csum_copy_err:
2276f58a
PA		 1942 if (!__sk_queue_drop_skb(sk, &udp_sk(sk)->reader_queue, skb, flags,
1943 udp_skb_destructor)) {
6aef70a8
ED		 1944 UDP_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
1945 UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
6a5dc9e5 1946 }
850cbadd 1947 kfree_skb(skb);
db8dac20 1948
beb39db5
ED		 1949 /* starting over for a new packet, but check if we need to yield */
1950 cond_resched();
9cfaa8de 1951 msg->msg_flags &= ~MSG_TRUNC;
db8dac20
DM		 1952 goto try_again;
1953}
1954
d74bad4e
AI		 1955int udp_pre_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
1956{
1957 /* This check is replicated from __ip4_datagram_connect() and
1958 * intended to prevent BPF program called below from accessing bytes
1959 * that are out of the bound specified by user in addr_len.
1960 */
1961 if (addr_len < sizeof(struct sockaddr_in))
1962 return -EINVAL;
1963
1964 return BPF_CGROUP_RUN_PROG_INET4_CONNECT_LOCK(sk, uaddr);
1965}
1966EXPORT_SYMBOL(udp_pre_connect);
1967
286c72de 1968int __udp_disconnect(struct sock *sk, int flags)
1da177e4
LT		 1969{
1970 struct inet_sock *inet = inet_sk(sk);
1971 /*
1972 * 1003.1g - break association.
1973 */
e905a9ed 1974
1da177e4 1975 sk->sk_state = TCP_CLOSE;
c720c7e8
ED		 1976 inet->inet_daddr = 0;
1977 inet->inet_dport = 0;
bdeab991 1978 sock_rps_reset_rxhash(sk);
1da177e4 1979 sk->sk_bound_dev_if = 0;
303d0403 1980 if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK)) {
1da177e4 1981 inet_reset_saddr(sk);
303d0403
WB		 1982 if (sk->sk_prot->rehash &&
1983 (sk->sk_userlocks & SOCK_BINDPORT_LOCK))
1984 sk->sk_prot->rehash(sk);
1985 }
1da177e4
LT		 1986
1987 if (!(sk->sk_userlocks & SOCK_BINDPORT_LOCK)) {
1988 sk->sk_prot->unhash(sk);
c720c7e8 1989 inet->inet_sport = 0;
1da177e4
LT		 1990 }
1991 sk_dst_reset(sk);
1992 return 0;
1993}
286c72de
ED		 1994EXPORT_SYMBOL(__udp_disconnect);
1995
1996int udp_disconnect(struct sock *sk, int flags)
1997{
1998 lock_sock(sk);
1999 __udp_disconnect(sk, flags);
2000 release_sock(sk);
2001 return 0;
2002}
c482c568 2003EXPORT_SYMBOL(udp_disconnect);
1da177e4 2004
645ca708
ED		 2005void udp_lib_unhash(struct sock *sk)
2006{
723b4610
ED		 2007 if (sk_hashed(sk)) {
2008 struct udp_table *udptable = sk->sk_prot->h.udp_table;
512615b6
ED		 2009 struct udp_hslot *hslot, *hslot2;
2010
2011 hslot = udp_hashslot(udptable, sock_net(sk),
2012 udp_sk(sk)->udp_port_hash);
2013 hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash);
645ca708 2014
723b4610 2015 spin_lock_bh(&hslot->lock);
e32ea7e7
CG		 2016 if (rcu_access_pointer(sk->sk_reuseport_cb))
2017 reuseport_detach_sock(sk);
ca065d0c 2018 if (sk_del_node_init_rcu(sk)) {
fdcc8aa9 2019 hslot->count--;
c720c7e8 2020 inet_sk(sk)->inet_num = 0;
723b4610 2021 sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1);
512615b6
ED		 2022
2023 spin_lock(&hslot2->lock);
ca065d0c 2024 hlist_del_init_rcu(&udp_sk(sk)->udp_portaddr_node);
512615b6
ED		 2025 hslot2->count--;
2026 spin_unlock(&hslot2->lock);
723b4610
ED		 2027 }
2028 spin_unlock_bh(&hslot->lock);
645ca708 2029 }
645ca708
ED		 2030}
2031EXPORT_SYMBOL(udp_lib_unhash);
2032
719f8358
ED		 2033/*
2034 * inet_rcv_saddr was changed, we must rehash secondary hash
2035 */
2036void udp_lib_rehash(struct sock *sk, u16 newhash)
2037{
2038 if (sk_hashed(sk)) {
2039 struct udp_table *udptable = sk->sk_prot->h.udp_table;
2040 struct udp_hslot *hslot, *hslot2, *nhslot2;
2041
2042 hslot2 = udp_hashslot2(udptable, udp_sk(sk)->udp_portaddr_hash);
2043 nhslot2 = udp_hashslot2(udptable, newhash);
2044 udp_sk(sk)->udp_portaddr_hash = newhash;
e32ea7e7
CG		 2045
2046 if (hslot2 != nhslot2 ||
2047 rcu_access_pointer(sk->sk_reuseport_cb)) {
719f8358
ED		 2048 hslot = udp_hashslot(udptable, sock_net(sk),
2049 udp_sk(sk)->udp_port_hash);
2050 /* we must lock primary chain too */
2051 spin_lock_bh(&hslot->lock);
e32ea7e7
CG		 2052 if (rcu_access_pointer(sk->sk_reuseport_cb))
2053 reuseport_detach_sock(sk);
2054
2055 if (hslot2 != nhslot2) {
2056 spin_lock(&hslot2->lock);
ca065d0c 2057 hlist_del_init_rcu(&udp_sk(sk)->udp_portaddr_node);
e32ea7e7
CG		 2058 hslot2->count--;
2059 spin_unlock(&hslot2->lock);
2060
2061 spin_lock(&nhslot2->lock);
ca065d0c 2062 hlist_add_head_rcu(&udp_sk(sk)->udp_portaddr_node,
e32ea7e7
CG		 2063 &nhslot2->head);
2064 nhslot2->count++;
2065 spin_unlock(&nhslot2->lock);
2066 }
719f8358
ED		 2067
2068 spin_unlock_bh(&hslot->lock);
2069 }
2070 }
2071}
2072EXPORT_SYMBOL(udp_lib_rehash);
2073
8f6b5392 2074void udp_v4_rehash(struct sock *sk)
719f8358 2075{
f0b1e64c 2076 u16 new_hash = ipv4_portaddr_hash(sock_net(sk),
719f8358
ED		 2077 inet_sk(sk)->inet_rcv_saddr,
2078 inet_sk(sk)->inet_num);
2079 udp_lib_rehash(sk, new_hash);
2080}
2081
a3f96c47 2082static int __udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
93821778 2083{
fec5e652 2084 int rc;
766e9037 2085
005ec974 2086 if (inet_sk(sk)->inet_daddr) {
bdeab991 2087 sock_rps_save_rxhash(sk, skb);
005ec974 2088 sk_mark_napi_id(sk, skb);
2c8c56e1 2089 sk_incoming_cpu_update(sk);
e68b6e50
ED		 2090 } else {
2091 sk_mark_napi_id_once(sk, skb);
005ec974 2092 }
fec5e652 2093
850cbadd 2094 rc = __udp_enqueue_schedule_skb(sk, skb);
766e9037
ED		 2095 if (rc < 0) {
2096 int is_udplite = IS_UDPLITE(sk);
08d4c037 2097 int drop_reason;
93821778 2098
93821778 2099 /* Note that an ENOMEM error is charged twice */
08d4c037 2100 if (rc == -ENOMEM) {
e61da9e2 2101 UDP_INC_STATS(sock_net(sk), UDP_MIB_RCVBUFERRORS,
02c22347 2102 is_udplite);
08d4c037
MD		 2103 drop_reason = SKB_DROP_REASON_SOCKET_RCVBUFF;
2104 } else {
a3ce2b10
MD		 2105 UDP_INC_STATS(sock_net(sk), UDP_MIB_MEMERRORS,
2106 is_udplite);
08d4c037
MD		 2107 drop_reason = SKB_DROP_REASON_PROTO_MEM;
2108 }
e61da9e2 2109 UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
08d4c037 2110 kfree_skb_reason(skb, drop_reason);
296f7ea7 2111 trace_udp_fail_queue_rcv_skb(rc, sk);
766e9037 2112 return -1;
93821778
HX		 2113 }
2114
2115 return 0;
93821778
HX		 2116}
2117
db8dac20
DM		 2118/* returns:
2119 * -1: error
2120 * 0: success
2121 * >0: "udp encap" protocol resubmission
2122 *
2123 * Note that in the success and error cases, the skb is assumed to
2124 * have either been requeued or freed.
2125 */
cf329aa4 2126static int udp_queue_rcv_one_skb(struct sock *sk, struct sk_buff *skb)
db8dac20 2127{
1379a92d 2128 int drop_reason = SKB_DROP_REASON_NOT_SPECIFIED;
db8dac20 2129 struct udp_sock *up = udp_sk(sk);
db8dac20
DM		 2130 int is_udplite = IS_UDPLITE(sk);
2131
2132 /*
2133 * Charge it to the socket, dropping if the queue is full.
2134 */
1379a92d
MD		 2135 if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb)) {
2136 drop_reason = SKB_DROP_REASON_XFRM_POLICY;
db8dac20 2137 goto drop;
1379a92d 2138 }
895b5c9f 2139 nf_reset_ct(skb);
db8dac20 2140
88ab3108 2141 if (static_branch_unlikely(&udp_encap_needed_key) && up->encap_type) {
0ad92ad0
ED		 2142 int (*encap_rcv)(struct sock *sk, struct sk_buff *skb);
2143
db8dac20
DM		 2144 /*
2145 * This is an encapsulation socket so pass the skb to
2146 * the socket's udp_encap_rcv() hook. Otherwise, just
2147 * fall through and pass this up the UDP socket.
2148 * up->encap_rcv() returns the following value:
2149 * =0 if skb was successfully passed to the encap
2150 * handler or was discarded by it.
2151 * >0 if skb should be passed on to UDP.
2152 * <0 if skb should be resubmitted as proto -N
2153 */
2154
2155 /* if we're overly short, let UDP handle it */
6aa7de05 2156 encap_rcv = READ_ONCE(up->encap_rcv);
e5aed006 2157 if (encap_rcv) {
db8dac20
DM		 2158 int ret;
2159
0a80966b
TH		 2160 /* Verify checksum before giving to encap */
2161 if (udp_lib_checksum_complete(skb))
2162 goto csum_error;
2163
0ad92ad0 2164 ret = encap_rcv(sk, skb);
db8dac20 2165 if (ret <= 0) {
02c22347
ED		 2166 __UDP_INC_STATS(sock_net(sk),
2167 UDP_MIB_INDATAGRAMS,
2168 is_udplite);
db8dac20
DM		 2169 return -ret;
2170 }
2171 }
2172
2173 /* FALLTHROUGH -- it's a UDP Packet */
2174 }
2175
2176 /*
2177 * UDP-Lite specific tests, ignored on UDP sockets
2178 */
b0a42277 2179 if ((up->pcflag & UDPLITE_RECV_CC) && UDP_SKB_CB(skb)->partial_cov) {
db8dac20
DM		 2180
2181 /*
2182 * MIB statistics other than incrementing the error count are
2183 * disabled for the following two types of errors: these depend
2184 * on the application settings, not on the functioning of the
2185 * protocol stack as such.
2186 *
2187 * RFC 3828 here recommends (sec 3.3): "There should also be a
2188 * way ... to ... at least let the receiving application block
2189 * delivery of packets with coverage values less than a value
2190 * provided by the application."
2191 */
2192 if (up->pcrlen == 0) { /* full coverage was set */
ba7a46f1
JP		 2193 net_dbg_ratelimited("UDPLite: partial coverage %d while full coverage %d requested\n",
2194 UDP_SKB_CB(skb)->cscov, skb->len);
db8dac20
DM		 2195 goto drop;
2196 }
2197 /* The next case involves violating the min. coverage requested
2198 * by the receiver. This is subtle: if receiver wants x and x is
2199 * greater than the buffersize/MTU then receiver will complain
2200 * that it wants x while sender emits packets of smaller size y.
2201 * Therefore the above ...()->partial_cov statement is essential.
2202 */
2203 if (UDP_SKB_CB(skb)->cscov < up->pcrlen) {
ba7a46f1
JP		 2204 net_dbg_ratelimited("UDPLite: coverage %d too small, need min %d\n",
2205 UDP_SKB_CB(skb)->cscov, up->pcrlen);
db8dac20
DM		 2206 goto drop;
2207 }
2208 }
2209
dd99e425 2210 prefetch(&sk->sk_rmem_alloc);
ce25d66a
ED		 2211 if (rcu_access_pointer(sk->sk_filter) &&
2212 udp_lib_checksum_complete(skb))
e6afc8ac 2213 goto csum_error;
ce25d66a 2214
1379a92d
MD		 2215 if (sk_filter_trim_cap(sk, skb, sizeof(struct udphdr))) {
2216 drop_reason = SKB_DROP_REASON_SOCKET_FILTER;
a6127697 2217 goto drop;
1379a92d 2218 }
db8dac20 2219
e6afc8ac 2220 udp_csum_pull_header(skb);
db8dac20 2221
fbf8866d 2222 ipv4_pktinfo_prepare(sk, skb);
850cbadd 2223 return __udp_queue_rcv_skb(sk, skb);
db8dac20 2224
6a5dc9e5 2225csum_error:
1379a92d 2226 drop_reason = SKB_DROP_REASON_UDP_CSUM;
02c22347 2227 __UDP_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, is_udplite);
db8dac20 2228drop:
02c22347 2229 __UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, is_udplite);
8edf19c2 2230 atomic_inc(&sk->sk_drops);
1379a92d 2231 kfree_skb_reason(skb, drop_reason);
db8dac20
DM		 2232 return -1;
2233}
2234
cf329aa4
PA		 2235static int udp_queue_rcv_skb(struct sock *sk, struct sk_buff *skb)
2236{
2237 struct sk_buff *next, *segs;
2238 int ret;
2239
2240 if (likely(!udp_unexpected_gso(sk, skb)))
2241 return udp_queue_rcv_one_skb(sk, skb);
2242
a08e7fd9 2243 BUILD_BUG_ON(sizeof(struct udp_skb_cb) > SKB_GSO_CB_OFFSET);
cf329aa4
PA		 2244 __skb_push(skb, -skb_mac_offset(skb));
2245 segs = udp_rcv_segment(sk, skb, true);
1a186c14 2246 skb_list_walk_safe(segs, skb, next) {
cf329aa4 2247 __skb_pull(skb, skb_transport_offset(skb));
000ac44d
PA		 2248
2249 udp_post_segment_fix_csum(skb);
cf329aa4
PA		 2250 ret = udp_queue_rcv_one_skb(sk, skb);
2251 if (ret > 0)
10c678bd 2252 ip_protocol_deliver_rcu(dev_net(skb->dev), skb, ret);
cf329aa4
PA		 2253 }
2254 return 0;
2255}
2256
97502231 2257/* For TCP sockets, sk_rx_dst is protected by socket lock
e47eb5df 2258 * For UDP, we use xchg() to guard against concurrent changes.
97502231 2259 */
64f0f5d1 2260bool udp_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst)
421b3885 2261{
97502231
ED		 2262 struct dst_entry *old;
2263
d24406c8 2264 if (dst_hold_safe(dst)) {
8f905c0e 2265 old = xchg((__force struct dst_entry **)&sk->sk_rx_dst, dst);
d24406c8 2266 dst_release(old);
64f0f5d1 2267 return old != dst;
d24406c8 2268 }
64f0f5d1 2269 return false;
421b3885 2270}
c9f2c1ae 2271EXPORT_SYMBOL(udp_sk_rx_dst_set);
421b3885 2272
db8dac20
DM		 2273/*
2274 * Multicasts and broadcasts go to each listener.
2275 *
1240d137 2276 * Note: called only from the BH handler context.
db8dac20 2277 */
e3163493 2278static int __udp4_lib_mcast_deliver(struct net *net, struct sk_buff *skb,
db8dac20
DM		 2279 struct udphdr *uh,
2280 __be32 saddr, __be32 daddr,
36cbb245
RJ		 2281 struct udp_table *udptable,
2282 int proto)
db8dac20 2283{
ca065d0c 2284 struct sock *sk, *first = NULL;
5cf3d461
DH		 2285 unsigned short hnum = ntohs(uh->dest);
2286 struct udp_hslot *hslot = udp_hashslot(udptable, net, hnum);
2dc41cff 2287 unsigned int hash2 = 0, hash2_any = 0, use_hash2 = (hslot->count > 10);
ca065d0c
ED		 2288 unsigned int offset = offsetof(typeof(*sk), sk_node);
2289 int dif = skb->dev->ifindex;
fb74c277 2290 int sdif = inet_sdif(skb);
ca065d0c
ED		 2291 struct hlist_node *node;
2292 struct sk_buff *nskb;
2dc41cff
DH		 2293
2294 if (use_hash2) {
f0b1e64c 2295 hash2_any = ipv4_portaddr_hash(net, htonl(INADDR_ANY), hnum) &
73e2d5e3 2296 udptable->mask;
f0b1e64c 2297 hash2 = ipv4_portaddr_hash(net, daddr, hnum) & udptable->mask;
2dc41cff 2298start_lookup:
73e2d5e3 2299 hslot = &udptable->hash2[hash2];
2dc41cff
DH		 2300 offset = offsetof(typeof(*sk), __sk_common.skc_portaddr_node);
2301 }
db8dac20 2302
ca065d0c
ED		 2303 sk_for_each_entry_offset_rcu(sk, node, &hslot->head, offset) {
2304 if (!__udp_is_mcast_sock(net, sk, uh->dest, daddr,
fb74c277 2305 uh->source, saddr, dif, sdif, hnum))
ca065d0c
ED		 2306 continue;
2307
2308 if (!first) {
2309 first = sk;
2310 continue;
1240d137 2311 }
ca065d0c 2312 nskb = skb_clone(skb, GFP_ATOMIC);
1240d137 2313
ca065d0c
ED		 2314 if (unlikely(!nskb)) {
2315 atomic_inc(&sk->sk_drops);
02c22347
ED		 2316 __UDP_INC_STATS(net, UDP_MIB_RCVBUFERRORS,
2317 IS_UDPLITE(sk));
2318 __UDP_INC_STATS(net, UDP_MIB_INERRORS,
2319 IS_UDPLITE(sk));
ca065d0c
ED		 2320 continue;
2321 }
2322 if (udp_queue_rcv_skb(sk, nskb) > 0)
2323 consume_skb(nskb);
2324 }
1240d137 2325
2dc41cff
DH		 2326 /* Also lookup *:port if we are using hash2 and haven't done so yet. */
2327 if (use_hash2 && hash2 != hash2_any) {
2328 hash2 = hash2_any;
2329 goto start_lookup;
2330 }
2331
ca065d0c
ED		 2332 if (first) {
2333 if (udp_queue_rcv_skb(first, skb) > 0)
2334 consume_skb(skb);
1240d137 2335 } else {
ca065d0c 2336 kfree_skb(skb);
02c22347
ED		 2337 __UDP_INC_STATS(net, UDP_MIB_IGNOREDMULTI,
2338 proto == IPPROTO_UDPLITE);
1240d137 2339 }
db8dac20
DM		 2340 return 0;
2341}
2342
2343/* Initialize UDP checksum. If exited with zero value (success),
2344 * CHECKSUM_UNNECESSARY means, that no more checks are required.
666a3d6e 2345 * Otherwise, csum completion requires checksumming packet body,
db8dac20
DM		 2346 * including udp header and folding it to skb->csum.
2347 */
2348static inline int udp4_csum_init(struct sk_buff *skb, struct udphdr *uh,
2349 int proto)
2350{
db8dac20
DM		 2351 int err;
2352
2353 UDP_SKB_CB(skb)->partial_cov = 0;
2354 UDP_SKB_CB(skb)->cscov = skb->len;
2355
2356 if (proto == IPPROTO_UDPLITE) {
2357 err = udplite_checksum_init(skb, uh);
2358 if (err)
2359 return err;
15f35d49
AK		 2360
2361 if (UDP_SKB_CB(skb)->partial_cov) {
2362 skb->csum = inet_compute_pseudo(skb, proto);
2363 return 0;
2364 }
db8dac20
DM		 2365 }
2366
b46d9f62
HFS		 2367 /* Note, we are only interested in != 0 or == 0, thus the
2368 * force to int.
2369 */
db4f1be3
ST		 2370 err = (__force int)skb_checksum_init_zero_check(skb, proto, uh->check,
2371 inet_compute_pseudo);
2372 if (err)
2373 return err;
2374
2375 if (skb->ip_summed == CHECKSUM_COMPLETE && !skb->csum_valid) {
2376 /* If SW calculated the value, we know it's bad */
2377 if (skb->csum_complete_sw)
2378 return 1;
2379
2380 /* HW says the value is bad. Let's validate that.
2381 * skb->csum is no longer the full packet checksum,
2382 * so don't treat it as such.
2383 */
2384 skb_checksum_complete_unset(skb);
2385 }
2386
2387 return 0;
db8dac20
DM		 2388}
2389
2b5a9217
PA		 2390/* wrapper for udp_queue_rcv_skb tacking care of csum conversion and
2391 * return code conversion for ip layer consumption
2392 */
2393static int udp_unicast_rcv_skb(struct sock *sk, struct sk_buff *skb,
2394 struct udphdr *uh)
2395{
2396 int ret;
2397
2398 if (inet_get_convert_csum(sk) && uh->check && !IS_UDPLITE(sk))
e4aa33ad 2399 skb_checksum_try_convert(skb, IPPROTO_UDP, inet_compute_pseudo);
2b5a9217
PA		 2400
2401 ret = udp_queue_rcv_skb(sk, skb);
2402
2403 /* a return value > 0 means to resubmit the input, but
2404 * it wants the return to be -protocol, or 0
2405 */
2406 if (ret > 0)
2407 return -ret;
2408 return 0;
2409}
2410
db8dac20
DM		 2411/*
2412 * All we need to do is get the socket, and then do a checksum.
2413 */
2414
645ca708 2415int __udp4_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
db8dac20
DM		 2416 int proto)
2417{
2418 struct sock *sk;
7b5e56f9 2419 struct udphdr *uh;
db8dac20 2420 unsigned short ulen;
adf30907 2421 struct rtable *rt = skb_rtable(skb);
2783ef23 2422 __be32 saddr, daddr;
0283328e 2423 struct net *net = dev_net(skb->dev);
71489e21 2424 bool refcounted;
1c7fab70
MD		 2425 int drop_reason;
2426
2427 drop_reason = SKB_DROP_REASON_NOT_SPECIFIED;
db8dac20
DM		 2428
2429 /*
2430 * Validate the packet.
2431 */
2432 if (!pskb_may_pull(skb, sizeof(struct udphdr)))
2433 goto drop; /* No space for header. */
2434
7b5e56f9 2435 uh = udp_hdr(skb);
db8dac20 2436 ulen = ntohs(uh->len);
ccc2d97c
BM		 2437 saddr = ip_hdr(skb)->saddr;
2438 daddr = ip_hdr(skb)->daddr;
2439
db8dac20
DM		 2440 if (ulen > skb->len)
2441 goto short_packet;
2442
2443 if (proto == IPPROTO_UDP) {
2444 /* UDP validates ulen. */
2445 if (ulen < sizeof(*uh) || pskb_trim_rcsum(skb, ulen))
2446 goto short_packet;
2447 uh = udp_hdr(skb);
2448 }
2449
2450 if (udp4_csum_init(skb, uh, proto))
2451 goto csum_error;
2452
71489e21 2453 sk = skb_steal_sock(skb, &refcounted);
8afdd99a 2454 if (sk) {
97502231 2455 struct dst_entry *dst = skb_dst(skb);
421b3885 2456 int ret;
421b3885 2457
8f905c0e 2458 if (unlikely(rcu_dereference(sk->sk_rx_dst) != dst))
97502231 2459 udp_sk_rx_dst_set(sk, dst);
db8dac20 2460
2b5a9217 2461 ret = udp_unicast_rcv_skb(sk, skb, uh);
71489e21
JS		 2462 if (refcounted)
2463 sock_put(sk);
2b5a9217 2464 return ret;
421b3885 2465 }
db8dac20 2466
c18450a5
FF		 2467 if (rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST))
2468 return __udp4_lib_mcast_deliver(net, skb, uh,
36cbb245 2469 saddr, daddr, udptable, proto);
c18450a5
FF		 2470
2471 sk = __udp4_lib_lookup_skb(skb, uh->source, uh->dest, udptable);
2b5a9217
PA		 2472 if (sk)
2473 return udp_unicast_rcv_skb(sk, skb, uh);
db8dac20
DM		 2474
2475 if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
2476 goto drop;
895b5c9f 2477 nf_reset_ct(skb);
db8dac20
DM		 2478
2479 /* No socket. Drop packet silently, if checksum is wrong */
2480 if (udp_lib_checksum_complete(skb))
2481 goto csum_error;
2482
1c7fab70 2483 drop_reason = SKB_DROP_REASON_NO_SOCKET;
02c22347 2484 __UDP_INC_STATS(net, UDP_MIB_NOPORTS, proto == IPPROTO_UDPLITE);
db8dac20
DM		 2485 icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
2486
2487 /*
2488 * Hmm. We got an UDP packet to a port to which we
2489 * don't wanna listen. Ignore it.
2490 */
1c7fab70 2491 kfree_skb_reason(skb, drop_reason);
db8dac20
DM		 2492 return 0;
2493
2494short_packet:
1c7fab70 2495 drop_reason = SKB_DROP_REASON_PKT_TOO_SMALL;
ba7a46f1
JP		 2496 net_dbg_ratelimited("UDP%s: short packet: From %pI4:%u %d/%d to %pI4:%u\n",
2497 proto == IPPROTO_UDPLITE ? "Lite" : "",
2498 &saddr, ntohs(uh->source),
2499 ulen, skb->len,
2500 &daddr, ntohs(uh->dest));
db8dac20
DM		 2501 goto drop;
2502
2503csum_error:
2504 /*
2505 * RFC1122: OK. Discards the bad packet silently (as far as
2506 * the network is concerned, anyway) as per 4.1.3.4 (MUST).
2507 */
1c7fab70 2508 drop_reason = SKB_DROP_REASON_UDP_CSUM;
ba7a46f1
JP		 2509 net_dbg_ratelimited("UDP%s: bad checksum. From %pI4:%u to %pI4:%u ulen %d\n",
2510 proto == IPPROTO_UDPLITE ? "Lite" : "",
2511 &saddr, ntohs(uh->source), &daddr, ntohs(uh->dest),
2512 ulen);
02c22347 2513 __UDP_INC_STATS(net, UDP_MIB_CSUMERRORS, proto == IPPROTO_UDPLITE);
db8dac20 2514drop:
02c22347 2515 __UDP_INC_STATS(net, UDP_MIB_INERRORS, proto == IPPROTO_UDPLITE);
1c7fab70 2516 kfree_skb_reason(skb, drop_reason);
db8dac20
DM		 2517 return 0;
2518}
2519
421b3885
SB		 2520/* We can only early demux multicast if there is a single matching socket.
2521 * If more than one socket found returns NULL
2522 */
2523static struct sock *__udp4_lib_mcast_demux_lookup(struct net *net,
2524 __be16 loc_port, __be32 loc_addr,
2525 __be16 rmt_port, __be32 rmt_addr,
fb74c277 2526 int dif, int sdif)
421b3885
SB		 2527{
2528 struct sock *sk, *result;
421b3885 2529 unsigned short hnum = ntohs(loc_port);
ca065d0c 2530 unsigned int slot = udp_hashfn(net, hnum, udp_table.mask);
421b3885
SB		 2531 struct udp_hslot *hslot = &udp_table.hash[slot];
2532
63c6f81c
ED		 2533 /* Do not bother scanning a too big list */
2534 if (hslot->count > 10)
2535 return NULL;
2536
421b3885 2537 result = NULL;
ca065d0c
ED		 2538 sk_for_each_rcu(sk, &hslot->head) {
2539 if (__udp_is_mcast_sock(net, sk, loc_port, loc_addr,
fb74c277 2540 rmt_port, rmt_addr, dif, sdif, hnum)) {
ca065d0c
ED		 2541 if (result)
2542 return NULL;
421b3885 2543 result = sk;
421b3885
SB		 2544 }
2545 }
ca065d0c 2546
421b3885
SB		 2547 return result;
2548}
2549
2550/* For unicast we should only early demux connected sockets or we can
2551 * break forwarding setups. The chains here can be long so only check
2552 * if the first socket is an exact match and if not move on.
2553 */
2554static struct sock *__udp4_lib_demux_lookup(struct net *net,
2555 __be16 loc_port, __be32 loc_addr,
2556 __be16 rmt_port, __be32 rmt_addr,
3fa6f616 2557 int dif, int sdif)
421b3885 2558{
421b3885 2559 unsigned short hnum = ntohs(loc_port);
f0b1e64c 2560 unsigned int hash2 = ipv4_portaddr_hash(net, loc_addr, hnum);
421b3885
SB		 2561 unsigned int slot2 = hash2 & udp_table.mask;
2562 struct udp_hslot *hslot2 = &udp_table.hash2[slot2];
c7228317 2563 INET_ADDR_COOKIE(acookie, rmt_addr, loc_addr);
421b3885 2564 const __portpair ports = INET_COMBINED_PORTS(rmt_port, hnum);
ca065d0c 2565 struct sock *sk;
421b3885 2566
ca065d0c 2567 udp_portaddr_for_each_entry_rcu(sk, &hslot2->head) {
eda090c3 2568 if (inet_match(net, sk, acookie, ports, dif, sdif))
ca065d0c 2569 return sk;
421b3885
SB		 2570 /* Only check first socket in chain */
2571 break;
2572 }
ca065d0c 2573 return NULL;
421b3885
SB		 2574}
2575
7487449c 2576int udp_v4_early_demux(struct sk_buff *skb)
421b3885 2577{
610438b7 2578 struct net *net = dev_net(skb->dev);
bc044e8d 2579 struct in_device *in_dev = NULL;
610438b7
ED		 2580 const struct iphdr *iph;
2581 const struct udphdr *uh;
ca065d0c 2582 struct sock *sk = NULL;
421b3885 2583 struct dst_entry *dst;
421b3885 2584 int dif = skb->dev->ifindex;
fb74c277 2585 int sdif = inet_sdif(skb);
6e540309 2586 int ours;
421b3885
SB		 2587
2588 /* validate the packet */
2589 if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct udphdr)))
7487449c 2590 return 0;
421b3885 2591
610438b7
ED		 2592 iph = ip_hdr(skb);
2593 uh = udp_hdr(skb);
2594
996b44fc 2595 if (skb->pkt_type == PACKET_MULTICAST) {
bc044e8d 2596 in_dev = __in_dev_get_rcu(skb->dev);
6e540309
SB		 2597
2598 if (!in_dev)
7487449c 2599 return 0;
6e540309 2600
996b44fc
PA		 2601 ours = ip_check_mc_rcu(in_dev, iph->daddr, iph->saddr,
2602 iph->protocol);
2603 if (!ours)
2604 return 0;
ad0ea198 2605
421b3885 2606 sk = __udp4_lib_mcast_demux_lookup(net, uh->dest, iph->daddr,
fb74c277
DA		 2607 uh->source, iph->saddr,
2608 dif, sdif);
6e540309 2609 } else if (skb->pkt_type == PACKET_HOST) {
421b3885 2610 sk = __udp4_lib_demux_lookup(net, uh->dest, iph->daddr,
3fa6f616 2611 uh->source, iph->saddr, dif, sdif);
6e540309 2612 }
421b3885 2613
41c6d650 2614 if (!sk || !refcount_inc_not_zero(&sk->sk_refcnt))
7487449c 2615 return 0;
421b3885
SB		 2616
2617 skb->sk = sk;
82eabd9e 2618 skb->destructor = sock_efree;
8f905c0e 2619 dst = rcu_dereference(sk->sk_rx_dst);
421b3885
SB		 2620
2621 if (dst)
2622 dst = dst_check(dst, 0);
10e2eb87 2623 if (dst) {
bc044e8d
PA		 2624 u32 itag = 0;
2625
d24406c8
WW		 2626 /* set noref for now.
2627 * any place which wants to hold dst has to call
2628 * dst_hold_safe()
2629 */
2630 skb_dst_set_noref(skb, dst);
bc044e8d
PA		 2631
2632 /* for unconnected multicast sockets we need to validate
2633 * the source on each packet
2634 */
2635 if (!inet_sk(sk)->inet_daddr && in_dev)
2636 return ip_mc_validate_source(skb, iph->daddr,
8d2b51b0
GN		 2637 iph->saddr,
2638 iph->tos & IPTOS_RT_MASK,
bc044e8d 2639 skb->dev, in_dev, &itag);
10e2eb87 2640 }
7487449c 2641 return 0;
421b3885
SB		 2642}
2643
db8dac20
DM		 2644int udp_rcv(struct sk_buff *skb)
2645{
645ca708 2646 return __udp4_lib_rcv(skb, &udp_table, IPPROTO_UDP);
db8dac20
DM		 2647}
2648
7d06b2e0 2649void udp_destroy_sock(struct sock *sk)
db8dac20 2650{
44046a59 2651 struct udp_sock *up = udp_sk(sk);
8a74ad60 2652 bool slow = lock_sock_fast(sk);
a8b897c7
PA		 2653
2654 /* protects from races with udp_abort() */
2655 sock_set_flag(sk, SOCK_DEAD);
db8dac20 2656 udp_flush_pending_frames(sk);
8a74ad60 2657 unlock_sock_fast(sk, slow);
60fb9567
PA		 2658 if (static_branch_unlikely(&udp_encap_needed_key)) {
2659 if (up->encap_type) {
2660 void (*encap_destroy)(struct sock *sk);
2661 encap_destroy = READ_ONCE(up->encap_destroy);
2662 if (encap_destroy)
2663 encap_destroy(sk);
2664 }
2665 if (up->encap_enabled)
9c480601 2666 static_branch_dec(&udp_encap_needed_key);
44046a59 2667 }
db8dac20
DM		 2668}
2669
1da177e4
LT		 2670/*
2671 * Socket option code for UDP
2672 */
4c0a6cb0 2673int udp_lib_setsockopt(struct sock *sk, int level, int optname,
91ac1cca 2674 sockptr_t optval, unsigned int optlen,
4c0a6cb0 2675 int (*push_pending_frames)(struct sock *))
1da177e4
LT		 2676{
2677 struct udp_sock *up = udp_sk(sk);
1c19448c 2678 int val, valbool;
1da177e4 2679 int err = 0;
b2bf1e26 2680 int is_udplite = IS_UDPLITE(sk);
1da177e4 2681
c482c568 2682 if (optlen < sizeof(int))
1da177e4
LT		 2683 return -EINVAL;
2684
91ac1cca 2685 if (copy_from_sockptr(&val, optval, sizeof(val)))
1da177e4
LT		 2686 return -EFAULT;
2687
1c19448c
TH		 2688 valbool = val ? 1 : 0;
2689
6516c655 2690 switch (optname) {
1da177e4
LT		 2691 case UDP_CORK:
2692 if (val != 0) {
a9f59707 2693 WRITE_ONCE(up->corkflag, 1);
1da177e4 2694 } else {
a9f59707 2695 WRITE_ONCE(up->corkflag, 0);
1da177e4 2696 lock_sock(sk);
4243cdc2 2697 push_pending_frames(sk);
1da177e4
LT		 2698 release_sock(sk);
2699 }
2700 break;
e905a9ed 2701
1da177e4
LT		 2702 case UDP_ENCAP:
2703 switch (val) {
2704 case 0:
fd1ac07f 2705#ifdef CONFIG_XFRM
1da177e4
LT		 2706 case UDP_ENCAP_ESPINUDP:
2707 case UDP_ENCAP_ESPINUDP_NON_IKE:
0146dca7
SD		 2708#if IS_ENABLED(CONFIG_IPV6)
2709 if (sk->sk_family == AF_INET6)
2710 up->encap_rcv = ipv6_stub->xfrm6_udp_encap_rcv;
2711 else
2712#endif
2713 up->encap_rcv = xfrm4_udp_encap_rcv;
fd1ac07f 2714#endif
a8eceea8 2715 fallthrough;
342f0234 2716 case UDP_ENCAP_L2TPINUDP:
1da177e4 2717 up->encap_type = val;
60fb9567
PA		 2718 lock_sock(sk);
2719 udp_tunnel_encap_enable(sk->sk_socket);
2720 release_sock(sk);
1da177e4
LT		 2721 break;
2722 default:
2723 err = -ENOPROTOOPT;
2724 break;
2725 }
2726 break;
2727
1c19448c
TH		 2728 case UDP_NO_CHECK6_TX:
2729 up->no_check6_tx = valbool;
2730 break;
2731
2732 case UDP_NO_CHECK6_RX:
2733 up->no_check6_rx = valbool;
2734 break;
2735
bec1f6f6
WB		 2736 case UDP_SEGMENT:
2737 if (val < 0 || val > USHRT_MAX)
2738 return -EINVAL;
18a419ba 2739 WRITE_ONCE(up->gso_size, val);
bec1f6f6
WB		 2740 break;
2741
e20cf8d3
PA		 2742 case UDP_GRO:
2743 lock_sock(sk);
78352f73
PA		 2744
2745 /* when enabling GRO, accept the related GSO packet type */
e20cf8d3
PA		 2746 if (valbool)
2747 udp_tunnel_encap_enable(sk->sk_socket);
2748 up->gro_enabled = valbool;
78352f73 2749 up->accept_udp_l4 = valbool;
e20cf8d3
PA		 2750 release_sock(sk);
2751 break;
2752
ba4e58ec
GR		 2753 /*
2754 * UDP-Lite's partial checksum coverage (RFC 3828).
2755 */
2756 /* The sender sets actual checksum coverage length via this option.
2757 * The case coverage > packet length is handled by send module. */
2758 case UDPLITE_SEND_CSCOV:
b2bf1e26 2759 if (!is_udplite) /* Disable the option on UDP sockets */
ba4e58ec
GR		 2760 return -ENOPROTOOPT;
2761 if (val != 0 && val < 8) /* Illegal coverage: use default (8) */
2762 val = 8;
4be929be
AD		 2763 else if (val > USHRT_MAX)
2764 val = USHRT_MAX;
ba4e58ec
GR		 2765 up->pcslen = val;
2766 up->pcflag |= UDPLITE_SEND_CC;
2767 break;
2768
e905a9ed
YH		 2769 /* The receiver specifies a minimum checksum coverage value. To make
2770 * sense, this should be set to at least 8 (as done below). If zero is
ba4e58ec
GR		 2771 * used, this again means full checksum coverage. */
2772 case UDPLITE_RECV_CSCOV:
b2bf1e26 2773 if (!is_udplite) /* Disable the option on UDP sockets */
ba4e58ec
GR		 2774 return -ENOPROTOOPT;
2775 if (val != 0 && val < 8) /* Avoid silly minimal values. */
2776 val = 8;
4be929be
AD		 2777 else if (val > USHRT_MAX)
2778 val = USHRT_MAX;
ba4e58ec
GR		 2779 up->pcrlen = val;
2780 up->pcflag |= UDPLITE_RECV_CC;
2781 break;
2782
1da177e4
LT		 2783 default:
2784 err = -ENOPROTOOPT;
2785 break;
6516c655 2786 }
1da177e4
LT		 2787
2788 return err;
2789}
c482c568 2790EXPORT_SYMBOL(udp_lib_setsockopt);
1da177e4 2791
a7b75c5a
CH		 2792int udp_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval,
2793 unsigned int optlen)
db8dac20
DM		 2794{
2795 if (level == SOL_UDP || level == SOL_UDPLITE)
91ac1cca 2796 return udp_lib_setsockopt(sk, level, optname,
a7b75c5a 2797 optval, optlen,
db8dac20
DM		 2798 udp_push_pending_frames);
2799 return ip_setsockopt(sk, level, optname, optval, optlen);
2800}
2801
4c0a6cb0
GR		 2802int udp_lib_getsockopt(struct sock *sk, int level, int optname,
2803 char __user *optval, int __user *optlen)
1da177e4
LT		 2804{
2805 struct udp_sock *up = udp_sk(sk);
2806 int val, len;
2807
c482c568 2808 if (get_user(len, optlen))
1da177e4
LT		 2809 return -EFAULT;
2810
2811 len = min_t(unsigned int, len, sizeof(int));
e905a9ed 2812
6516c655 2813 if (len < 0)
1da177e4
LT		 2814 return -EINVAL;
2815
6516c655 2816 switch (optname) {
1da177e4 2817 case UDP_CORK:
a9f59707 2818 val = READ_ONCE(up->corkflag);
1da177e4
LT		 2819 break;
2820
2821 case UDP_ENCAP:
2822 val = up->encap_type;
2823 break;
2824
1c19448c
TH		 2825 case UDP_NO_CHECK6_TX:
2826 val = up->no_check6_tx;
2827 break;
2828
2829 case UDP_NO_CHECK6_RX:
2830 val = up->no_check6_rx;
2831 break;
2832
bec1f6f6 2833 case UDP_SEGMENT:
18a419ba 2834 val = READ_ONCE(up->gso_size);
bec1f6f6
WB		 2835 break;
2836
98184612
NM		 2837 case UDP_GRO:
2838 val = up->gro_enabled;
2839 break;
2840
ba4e58ec
GR		 2841 /* The following two cannot be changed on UDP sockets, the return is
2842 * always 0 (which corresponds to the full checksum coverage of UDP). */
2843 case UDPLITE_SEND_CSCOV:
2844 val = up->pcslen;
2845 break;
2846
2847 case UDPLITE_RECV_CSCOV:
2848 val = up->pcrlen;
2849 break;
2850
1da177e4
LT		 2851 default:
2852 return -ENOPROTOOPT;
6516c655 2853 }
1da177e4 2854
6516c655 2855 if (put_user(len, optlen))
e905a9ed 2856 return -EFAULT;
c482c568 2857 if (copy_to_user(optval, &val, len))
1da177e4 2858 return -EFAULT;
e905a9ed 2859 return 0;
1da177e4 2860}
c482c568 2861EXPORT_SYMBOL(udp_lib_getsockopt);
1da177e4 2862
db8dac20
DM		 2863int udp_getsockopt(struct sock *sk, int level, int optname,
2864 char __user *optval, int __user *optlen)
2865{
2866 if (level == SOL_UDP || level == SOL_UDPLITE)
2867 return udp_lib_getsockopt(sk, level, optname, optval, optlen);
2868 return ip_getsockopt(sk, level, optname, optval, optlen);
2869}
2870
1da177e4
LT		 2871/**
2872 * udp_poll - wait for a UDP event.
3628e3cb
AL		 2873 * @file: - file struct
2874 * @sock: - socket
2875 * @wait: - poll table
1da177e4 2876 *
e905a9ed 2877 * This is same as datagram poll, except for the special case of
1da177e4
LT		 2878 * blocking sockets. If application is using a blocking fd
2879 * and a packet with checksum error is in the queue;
2880 * then it could get return from select indicating data available
2881 * but then block when reading it. Add special case code
2882 * to work around these arguably broken applications.
2883 */
a11e1d43 2884__poll_t udp_poll(struct file *file, struct socket *sock, poll_table *wait)
1da177e4 2885{
a11e1d43 2886 __poll_t mask = datagram_poll(file, sock, wait);
1da177e4 2887 struct sock *sk = sock->sk;
ba4e58ec 2888
3ef7cf57 2889 if (!skb_queue_empty_lockless(&udp_sk(sk)->reader_queue))
a9a08845 2890 mask |= EPOLLIN | EPOLLRDNORM;
2276f58a 2891
1da177e4 2892 /* Check for false positives due to checksum errors */
a11e1d43 2893 if ((mask & EPOLLRDNORM) && !(file->f_flags & O_NONBLOCK) &&
e83c6744 2894 !(sk->sk_shutdown & RCV_SHUTDOWN) && first_packet_length(sk) == -1)
a9a08845 2895 mask &= ~(EPOLLIN | EPOLLRDNORM);
1da177e4 2896
af493388
CW		 2897 /* psock ingress_msg queue should not contain any bad checksum frames */
2898 if (sk_is_readable(sk))
2899 mask |= EPOLLIN | EPOLLRDNORM;
1da177e4 2900 return mask;
e905a9ed 2901
1da177e4 2902}
a11e1d43 2903EXPORT_SYMBOL(udp_poll);
1da177e4 2904
5d77dca8
DA		 2905int udp_abort(struct sock *sk, int err)
2906{
2907 lock_sock(sk);
2908
a8b897c7
PA		 2909 /* udp{v6}_destroy_sock() sets it under the sk lock, avoid racing
2910 * with close()
2911 */
2912 if (sock_flag(sk, SOCK_DEAD))
2913 goto out;
2914
5d77dca8 2915 sk->sk_err = err;
e3ae2365 2916 sk_error_report(sk);
286c72de 2917 __udp_disconnect(sk, 0);
5d77dca8 2918
a8b897c7 2919out:
5d77dca8
DA		 2920 release_sock(sk);
2921
2922 return 0;
2923}
2924EXPORT_SYMBOL_GPL(udp_abort);
2925
db8dac20 2926struct proto udp_prot = {
1e802951
TZ		 2927 .name = "UDP",
2928 .owner = THIS_MODULE,
2929 .close = udp_lib_close,
d74bad4e 2930 .pre_connect = udp_pre_connect,
1e802951
TZ		 2931 .connect = ip4_datagram_connect,
2932 .disconnect = udp_disconnect,
2933 .ioctl = udp_ioctl,
2934 .init = udp_init_sock,
2935 .destroy = udp_destroy_sock,
2936 .setsockopt = udp_setsockopt,
2937 .getsockopt = udp_getsockopt,
2938 .sendmsg = udp_sendmsg,
2939 .recvmsg = udp_recvmsg,
2940 .sendpage = udp_sendpage,
2941 .release_cb = ip4_datagram_release_cb,
2942 .hash = udp_lib_hash,
2943 .unhash = udp_lib_unhash,
2944 .rehash = udp_v4_rehash,
2945 .get_port = udp_v4_get_port,
91a760b2 2946 .put_port = udp_lib_unhash,
8a59f9d1
CW		 2947#ifdef CONFIG_BPF_SYSCALL
2948 .psock_update_sk_prot = udp_bpf_update_proto,
2949#endif
1e802951 2950 .memory_allocated = &udp_memory_allocated,
0defbb0a
ED		 2951 .per_cpu_fw_alloc = &udp_memory_per_cpu_fw_alloc,
2952
1e802951
TZ		 2953 .sysctl_mem = sysctl_udp_mem,
2954 .sysctl_wmem_offset = offsetof(struct net, ipv4.sysctl_udp_wmem_min),
2955 .sysctl_rmem_offset = offsetof(struct net, ipv4.sysctl_udp_rmem_min),
2956 .obj_size = sizeof(struct udp_sock),
2957 .h.udp_table = &udp_table,
1e802951 2958 .diag_destroy = udp_abort,
db8dac20 2959};
c482c568 2960EXPORT_SYMBOL(udp_prot);
1da177e4
LT		 2961
2962/* ------------------------------------------------------------------------ */
2963#ifdef CONFIG_PROC_FS
2964
645ca708 2965static struct sock *udp_get_first(struct seq_file *seq, int start)
1da177e4
LT		 2966{
2967 struct sock *sk;
9e8ca27a 2968 struct udp_seq_afinfo *afinfo;
1da177e4 2969 struct udp_iter_state *state = seq->private;
6f191efe 2970 struct net *net = seq_file_net(seq);
1da177e4 2971
9e8ca27a
YS		 2972 if (state->bpf_seq_afinfo)
2973 afinfo = state->bpf_seq_afinfo;
2974 else
359745d7 2975 afinfo = pde_data(file_inode(seq->file));
9e8ca27a 2976
a3d2599b 2977 for (state->bucket = start; state->bucket <= afinfo->udp_table->mask;
f86dcc5a 2978 ++state->bucket) {
a3d2599b 2979 struct udp_hslot *hslot = &afinfo->udp_table->hash[state->bucket];
f86dcc5a 2980
ca065d0c 2981 if (hlist_empty(&hslot->head))
f86dcc5a
ED		 2982 continue;
2983
645ca708 2984 spin_lock_bh(&hslot->lock);
ca065d0c 2985 sk_for_each(sk, &hslot->head) {
878628fb 2986 if (!net_eq(sock_net(sk), net))
a91275ef 2987 continue;
9e8ca27a
YS		 2988 if (afinfo->family == AF_UNSPEC ||
2989 sk->sk_family == afinfo->family)
1da177e4
LT		 2990 goto found;
2991 }
645ca708 2992 spin_unlock_bh(&hslot->lock);
1da177e4
LT		 2993 }
2994 sk = NULL;
2995found:
2996 return sk;
2997}
2998
2999static struct sock *udp_get_next(struct seq_file *seq, struct sock *sk)
3000{
9e8ca27a 3001 struct udp_seq_afinfo *afinfo;
1da177e4 3002 struct udp_iter_state *state = seq->private;
6f191efe 3003 struct net *net = seq_file_net(seq);
1da177e4 3004
9e8ca27a
YS		 3005 if (state->bpf_seq_afinfo)
3006 afinfo = state->bpf_seq_afinfo;
3007 else
359745d7 3008 afinfo = pde_data(file_inode(seq->file));
9e8ca27a 3009
1da177e4 3010 do {
ca065d0c 3011 sk = sk_next(sk);
9e8ca27a
YS		 3012 } while (sk && (!net_eq(sock_net(sk), net) ||
3013 (afinfo->family != AF_UNSPEC &&
3014 sk->sk_family != afinfo->family)));
1da177e4 3015
645ca708 3016 if (!sk) {
a3d2599b
CH		 3017 if (state->bucket <= afinfo->udp_table->mask)
3018 spin_unlock_bh(&afinfo->udp_table->hash[state->bucket].lock);
645ca708 3019 return udp_get_first(seq, state->bucket + 1);
1da177e4
LT		 3020 }
3021 return sk;
3022}
3023
3024static struct sock *udp_get_idx(struct seq_file *seq, loff_t pos)
3025{
645ca708 3026 struct sock *sk = udp_get_first(seq, 0);
1da177e4
LT		 3027
3028 if (sk)
6516c655 3029 while (pos && (sk = udp_get_next(seq, sk)) != NULL)
1da177e4
LT		 3030 --pos;
3031 return pos ? NULL : sk;
3032}
3033
a3d2599b 3034void *udp_seq_start(struct seq_file *seq, loff_t *pos)
1da177e4 3035{
30842f29 3036 struct udp_iter_state *state = seq->private;
f86dcc5a 3037 state->bucket = MAX_UDP_PORTS;
30842f29 3038
b50660f1 3039 return *pos ? udp_get_idx(seq, *pos-1) : SEQ_START_TOKEN;
1da177e4 3040}
a3d2599b 3041EXPORT_SYMBOL(udp_seq_start);
1da177e4 3042
a3d2599b 3043void *udp_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1da177e4
LT		 3044{
3045 struct sock *sk;
3046
b50660f1 3047 if (v == SEQ_START_TOKEN)
1da177e4
LT		 3048 sk = udp_get_idx(seq, 0);
3049 else
3050 sk = udp_get_next(seq, v);
3051
3052 ++*pos;
3053 return sk;
3054}
a3d2599b 3055EXPORT_SYMBOL(udp_seq_next);
1da177e4 3056
a3d2599b 3057void udp_seq_stop(struct seq_file *seq, void *v)
1da177e4 3058{
9e8ca27a 3059 struct udp_seq_afinfo *afinfo;
645ca708
ED		 3060 struct udp_iter_state *state = seq->private;
3061
9e8ca27a
YS		 3062 if (state->bpf_seq_afinfo)
3063 afinfo = state->bpf_seq_afinfo;
3064 else
359745d7 3065 afinfo = pde_data(file_inode(seq->file));
9e8ca27a 3066
a3d2599b
CH		 3067 if (state->bucket <= afinfo->udp_table->mask)
3068 spin_unlock_bh(&afinfo->udp_table->hash[state->bucket].lock);
1da177e4 3069}
a3d2599b 3070EXPORT_SYMBOL(udp_seq_stop);
db8dac20
DM		 3071
3072/* ------------------------------------------------------------------------ */
5e659e4c 3073static void udp4_format_sock(struct sock *sp, struct seq_file *f,
652586df 3074 int bucket)
db8dac20
DM		 3075{
3076 struct inet_sock *inet = inet_sk(sp);
c720c7e8
ED		 3077 __be32 dest = inet->inet_daddr;
3078 __be32 src = inet->inet_rcv_saddr;
3079 __u16 destp = ntohs(inet->inet_dport);
3080 __u16 srcp = ntohs(inet->inet_sport);
db8dac20 3081
f86dcc5a 3082 seq_printf(f, "%5d: %08X:%04X %08X:%04X"
ea9a0379 3083 " %02X %08X:%08X %02X:%08lX %08X %5u %8d %lu %d %pK %u",
db8dac20 3084 bucket, src, srcp, dest, destp, sp->sk_state,
31e6d363 3085 sk_wmem_alloc_get(sp),
6c206b20 3086 udp_rqueue_get(sp),
a7cb5a49
EB		 3087 0, 0L, 0,
3088 from_kuid_munged(seq_user_ns(f), sock_i_uid(sp)),
3089 0, sock_i_ino(sp),
41c6d650 3090 refcount_read(&sp->sk_refcnt), sp,
652586df 3091 atomic_read(&sp->sk_drops));
db8dac20
DM		 3092}
3093
3094int udp4_seq_show(struct seq_file *seq, void *v)
3095{
652586df 3096 seq_setwidth(seq, 127);
db8dac20 3097 if (v == SEQ_START_TOKEN)
6c25449e 3098 seq_puts(seq, " sl local_address rem_address st tx_queue "
db8dac20 3099 "rx_queue tr tm->when retrnsmt uid timeout "
cb61cb9b 3100 "inode ref pointer drops");
db8dac20 3101 else {
db8dac20
DM		 3102 struct udp_iter_state *state = seq->private;
3103
652586df 3104 udp4_format_sock(v, seq, state->bucket);
db8dac20 3105 }
652586df 3106 seq_pad(seq, '\n');
db8dac20
DM		 3107 return 0;
3108}
3109
5788b3a0
YS		 3110#ifdef CONFIG_BPF_SYSCALL
3111struct bpf_iter__udp {
3112 __bpf_md_ptr(struct bpf_iter_meta *, meta);
3113 __bpf_md_ptr(struct udp_sock *, udp_sk);
3114 uid_t uid __aligned(8);
3115 int bucket __aligned(8);
3116};
3117
3118static int udp_prog_seq_show(struct bpf_prog *prog, struct bpf_iter_meta *meta,
3119 struct udp_sock *udp_sk, uid_t uid, int bucket)
3120{
3121 struct bpf_iter__udp ctx;
3122
3123 meta->seq_num--; /* skip SEQ_START_TOKEN */
3124 ctx.meta = meta;
3125 ctx.udp_sk = udp_sk;
3126 ctx.uid = uid;
3127 ctx.bucket = bucket;
3128 return bpf_iter_run_prog(prog, &ctx);
3129}
3130
3131static int bpf_iter_udp_seq_show(struct seq_file *seq, void *v)
3132{
3133 struct udp_iter_state *state = seq->private;
3134 struct bpf_iter_meta meta;
3135 struct bpf_prog *prog;
3136 struct sock *sk = v;
3137 uid_t uid;
3138
3139 if (v == SEQ_START_TOKEN)
3140 return 0;
3141
3142 uid = from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk));
3143 meta.seq = seq;
3144 prog = bpf_iter_get_info(&meta, false);
3145 return udp_prog_seq_show(prog, &meta, v, uid, state->bucket);
3146}
3147
3148static void bpf_iter_udp_seq_stop(struct seq_file *seq, void *v)
3149{
3150 struct bpf_iter_meta meta;
3151 struct bpf_prog *prog;
3152
3153 if (!v) {
3154 meta.seq = seq;
3155 prog = bpf_iter_get_info(&meta, true);
3156 if (prog)
3157 (void)udp_prog_seq_show(prog, &meta, v, 0, 0);
3158 }
3159
3160 udp_seq_stop(seq, v);
3161}
3162
3163static const struct seq_operations bpf_iter_udp_seq_ops = {
3164 .start = udp_seq_start,
3165 .next = udp_seq_next,
3166 .stop = bpf_iter_udp_seq_stop,
3167 .show = bpf_iter_udp_seq_show,
3168};
3169#endif
3170
c3506372 3171const struct seq_operations udp_seq_ops = {
a3d2599b
CH		 3172 .start = udp_seq_start,
3173 .next = udp_seq_next,
3174 .stop = udp_seq_stop,
3175 .show = udp4_seq_show,
3176};
c3506372 3177EXPORT_SYMBOL(udp_seq_ops);
73cb88ec 3178
db8dac20 3179static struct udp_seq_afinfo udp4_seq_afinfo = {
db8dac20 3180 .family = AF_INET,
645ca708 3181 .udp_table = &udp_table,
db8dac20
DM		 3182};
3183
2c8c1e72 3184static int __net_init udp4_proc_init_net(struct net *net)
15439feb 3185{
c3506372
CH		 3186 if (!proc_create_net_data("udp", 0444, net->proc_net, &udp_seq_ops,
3187 sizeof(struct udp_iter_state), &udp4_seq_afinfo))
a3d2599b
CH		 3188 return -ENOMEM;
3189 return 0;
15439feb
PE		 3190}
3191
2c8c1e72 3192static void __net_exit udp4_proc_exit_net(struct net *net)
15439feb 3193{
a3d2599b 3194 remove_proc_entry("udp", net->proc_net);
15439feb
PE		 3195}
3196
3197static struct pernet_operations udp4_net_ops = {
3198 .init = udp4_proc_init_net,
3199 .exit = udp4_proc_exit_net,
3200};
3201
db8dac20
DM		 3202int __init udp4_proc_init(void)
3203{
15439feb 3204 return register_pernet_subsys(&udp4_net_ops);
db8dac20
DM		 3205}
3206
3207void udp4_proc_exit(void)
3208{
15439feb 3209 unregister_pernet_subsys(&udp4_net_ops);
db8dac20 3210}
1da177e4
LT		 3211#endif /* CONFIG_PROC_FS */
3212
f86dcc5a
ED		 3213static __initdata unsigned long uhash_entries;
3214static int __init set_uhash_entries(char *str)
645ca708 3215{
413c27d8
EZ		 3216 ssize_t ret;
3217
f86dcc5a
ED		 3218 if (!str)
3219 return 0;
413c27d8
EZ		 3220
3221 ret = kstrtoul(str, 0, &uhash_entries);
3222 if (ret)
3223 return 0;
3224
f86dcc5a
ED		 3225 if (uhash_entries && uhash_entries < UDP_HTABLE_SIZE_MIN)
3226 uhash_entries = UDP_HTABLE_SIZE_MIN;
3227 return 1;
3228}
3229__setup("uhash_entries=", set_uhash_entries);
645ca708 3230
f86dcc5a
ED		 3231void __init udp_table_init(struct udp_table *table, const char *name)
3232{
3233 unsigned int i;
3234
31fe62b9
TB		 3235 table->hash = alloc_large_system_hash(name,
3236 2 * sizeof(struct udp_hslot),
3237 uhash_entries,
3238 21, /* one slot per 2 MB */
3239 0,
3240 &table->log,
3241 &table->mask,
3242 UDP_HTABLE_SIZE_MIN,
3243 64 * 1024);
3244
512615b6 3245 table->hash2 = table->hash + (table->mask + 1);
f86dcc5a 3246 for (i = 0; i <= table->mask; i++) {
ca065d0c 3247 INIT_HLIST_HEAD(&table->hash[i].head);
fdcc8aa9 3248 table->hash[i].count = 0;
645ca708
ED		 3249 spin_lock_init(&table->hash[i].lock);
3250 }
512615b6 3251 for (i = 0; i <= table->mask; i++) {
ca065d0c 3252 INIT_HLIST_HEAD(&table->hash2[i].head);
512615b6
ED		 3253 table->hash2[i].count = 0;
3254 spin_lock_init(&table->hash2[i].lock);
3255 }
645ca708
ED		 3256}
3257
723b8e46
TH		 3258u32 udp_flow_hashrnd(void)
3259{
3260 static u32 hashrnd __read_mostly;
3261
3262 net_get_random_once(&hashrnd, sizeof(hashrnd));
3263
3264 return hashrnd;
3265}
3266EXPORT_SYMBOL(udp_flow_hashrnd);
3267
1e802951
TZ		 3268static void __udp_sysctl_init(struct net *net)
3269{
100fdd1f
ED		 3270 net->ipv4.sysctl_udp_rmem_min = PAGE_SIZE;
3271 net->ipv4.sysctl_udp_wmem_min = PAGE_SIZE;
1e802951
TZ		 3272
3273#ifdef CONFIG_NET_L3_MASTER_DEV
3274 net->ipv4.sysctl_udp_l3mdev_accept = 0;
3275#endif
3276}
3277
3278static int __net_init udp_sysctl_init(struct net *net)
3279{
3280 __udp_sysctl_init(net);
3281 return 0;
3282}
3283
3284static struct pernet_operations __net_initdata udp_sysctl_ops = {
fc18999e 3285 .init = udp_sysctl_init,
1e802951
TZ		 3286};
3287
5788b3a0
YS		 3288#if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS)
3289DEFINE_BPF_ITER_FUNC(udp, struct bpf_iter_meta *meta,
3290 struct udp_sock *udp_sk, uid_t uid, int bucket)
3291
f9c79272 3292static int bpf_iter_init_udp(void *priv_data, struct bpf_iter_aux_info *aux)
5788b3a0
YS		 3293{
3294 struct udp_iter_state *st = priv_data;
3295 struct udp_seq_afinfo *afinfo;
3296 int ret;
3297
3298 afinfo = kmalloc(sizeof(*afinfo), GFP_USER | __GFP_NOWARN);
3299 if (!afinfo)
3300 return -ENOMEM;
3301
3302 afinfo->family = AF_UNSPEC;
3303 afinfo->udp_table = &udp_table;
3304 st->bpf_seq_afinfo = afinfo;
f9c79272 3305 ret = bpf_iter_init_seq_net(priv_data, aux);
5788b3a0
YS		 3306 if (ret)
3307 kfree(afinfo);
3308 return ret;
3309}
3310
3311static void bpf_iter_fini_udp(void *priv_data)
3312{
3313 struct udp_iter_state *st = priv_data;
3314
3315 kfree(st->bpf_seq_afinfo);
3316 bpf_iter_fini_seq_net(priv_data);
3317}
3318
14fc6bd6 3319static const struct bpf_iter_seq_info udp_seq_info = {
5788b3a0
YS		 3320 .seq_ops = &bpf_iter_udp_seq_ops,
3321 .init_seq_private = bpf_iter_init_udp,
3322 .fini_seq_private = bpf_iter_fini_udp,
3323 .seq_priv_size = sizeof(struct udp_iter_state),
14fc6bd6
YS		 3324};
3325
3326static struct bpf_iter_reg udp_reg_info = {
3327 .target = "udp",
5788b3a0
YS		 3328 .ctx_arg_info_size = 1,
3329 .ctx_arg_info = {
3330 { offsetof(struct bpf_iter__udp, udp_sk),
3331 PTR_TO_BTF_ID_OR_NULL },
3332 },
14fc6bd6 3333 .seq_info = &udp_seq_info,
5788b3a0
YS		 3334};
3335
3336static void __init bpf_iter_register(void)
3337{
951cf368 3338 udp_reg_info.ctx_arg_info[0].btf_id = btf_sock_ids[BTF_SOCK_TYPE_UDP];
5788b3a0
YS		 3339 if (bpf_iter_reg_target(&udp_reg_info))
3340 pr_warn("Warning: could not register bpf iterator udp\n");
3341}
3342#endif
3343
95766fff
HA		 3344void __init udp_init(void)
3345{
f03d78db 3346 unsigned long limit;
4b272750 3347 unsigned int i;
95766fff 3348
f86dcc5a 3349 udp_table_init(&udp_table, "UDP");
f03d78db 3350 limit = nr_free_buffer_pages() / 8;
95766fff
HA		 3351 limit = max(limit, 128UL);
3352 sysctl_udp_mem[0] = limit / 4 * 3;
3353 sysctl_udp_mem[1] = limit;
3354 sysctl_udp_mem[2] = sysctl_udp_mem[0] * 2;
3355
1e802951 3356 __udp_sysctl_init(&init_net);
4b272750
ED		 3357
3358 /* 16 spinlocks per cpu */
3359 udp_busylocks_log = ilog2(nr_cpu_ids) + 4;
3360 udp_busylocks = kmalloc(sizeof(spinlock_t) << udp_busylocks_log,
3361 GFP_KERNEL);
3362 if (!udp_busylocks)
3363 panic("UDP: failed to alloc udp_busylocks\n");
3364 for (i = 0; i < (1U << udp_busylocks_log); i++)
3365 spin_lock_init(udp_busylocks + i);
1e802951
TZ		 3366
3367 if (register_pernet_subsys(&udp_sysctl_ops))
3368 panic("UDP: failed to init sysctl parameters.\n");
5788b3a0
YS		 3369
3370#if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_PROC_FS)
3371 bpf_iter_register();
3372#endif
95766fff 3373}
Linux 6.x block layer and io_uring tree(s)