blob: 8781a92ea4b6e4ee9ceeb763dae01970e7f4438a [file] [log] [blame]
Thomas Gleixner2874c5f2019-05-27 08:55:01 +02001// SPDX-License-Identifier: GPL-2.0-or-later
Linus Torvalds1da177e2005-04-16 15:20:36 -07002/*
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 * Implementation of the Transmission Control Protocol(TCP).
8 *
Jesper Juhl02c30a82005-05-05 16:16:16 -07009 * Authors: Ross Biro
Linus Torvalds1da177e2005-04-16 15:20:36 -070010 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
11 * Mark Evans, <evansmp@uhura.aston.ac.uk>
12 * Corey Minyard <wf-rch!minyard@relay.EU.net>
13 * Florian La Roche, <flla@stud.uni-sb.de>
14 * Charles Hedrick, <hedrick@klinzhai.rutgers.edu>
15 * Linus Torvalds, <torvalds@cs.helsinki.fi>
16 * Alan Cox, <gw4pts@gw4pts.ampr.org>
17 * Matthew Dillon, <dillon@apollo.west.oic.com>
18 * Arnt Gulbrandsen, <agulbra@nvg.unit.no>
19 * Jorge Cwik, <jorge@laser.satlink.net>
20 *
21 * Fixes:
22 * Alan Cox : Numerous verify_area() calls
23 * Alan Cox : Set the ACK bit on a reset
24 * Alan Cox : Stopped it crashing if it closed while
25 * sk->inuse=1 and was trying to connect
26 * (tcp_err()).
27 * Alan Cox : All icmp error handling was broken
28 * pointers passed where wrong and the
29 * socket was looked up backwards. Nobody
30 * tested any icmp error code obviously.
31 * Alan Cox : tcp_err() now handled properly. It
32 * wakes people on errors. poll
33 * behaves and the icmp error race
34 * has gone by moving it into sock.c
35 * Alan Cox : tcp_send_reset() fixed to work for
36 * everything not just packets for
37 * unknown sockets.
38 * Alan Cox : tcp option processing.
39 * Alan Cox : Reset tweaked (still not 100%) [Had
40 * syn rule wrong]
41 * Herp Rosmanith : More reset fixes
42 * Alan Cox : No longer acks invalid rst frames.
43 * Acking any kind of RST is right out.
44 * Alan Cox : Sets an ignore me flag on an rst
45 * receive otherwise odd bits of prattle
46 * escape still
47 * Alan Cox : Fixed another acking RST frame bug.
48 * Should stop LAN workplace lockups.
49 * Alan Cox : Some tidyups using the new skb list
50 * facilities
51 * Alan Cox : sk->keepopen now seems to work
52 * Alan Cox : Pulls options out correctly on accepts
53 * Alan Cox : Fixed assorted sk->rqueue->next errors
54 * Alan Cox : PSH doesn't end a TCP read. Switched a
55 * bit to skb ops.
56 * Alan Cox : Tidied tcp_data to avoid a potential
57 * nasty.
58 * Alan Cox : Added some better commenting, as the
59 * tcp is hard to follow
60 * Alan Cox : Removed incorrect check for 20 * psh
61 * Michael O'Reilly : ack < copied bug fix.
62 * Johannes Stille : Misc tcp fixes (not all in yet).
63 * Alan Cox : FIN with no memory -> CRASH
64 * Alan Cox : Added socket option proto entries.
65 * Also added awareness of them to accept.
66 * Alan Cox : Added TCP options (SOL_TCP)
67 * Alan Cox : Switched wakeup calls to callbacks,
68 * so the kernel can layer network
69 * sockets.
70 * Alan Cox : Use ip_tos/ip_ttl settings.
71 * Alan Cox : Handle FIN (more) properly (we hope).
72 * Alan Cox : RST frames sent on unsynchronised
73 * state ack error.
74 * Alan Cox : Put in missing check for SYN bit.
75 * Alan Cox : Added tcp_select_window() aka NET2E
76 * window non shrink trick.
77 * Alan Cox : Added a couple of small NET2E timer
78 * fixes
79 * Charles Hedrick : TCP fixes
80 * Toomas Tamm : TCP window fixes
81 * Alan Cox : Small URG fix to rlogin ^C ack fight
82 * Charles Hedrick : Rewrote most of it to actually work
83 * Linus : Rewrote tcp_read() and URG handling
84 * completely
85 * Gerhard Koerting: Fixed some missing timer handling
86 * Matthew Dillon : Reworked TCP machine states as per RFC
87 * Gerhard Koerting: PC/TCP workarounds
88 * Adam Caldwell : Assorted timer/timing errors
89 * Matthew Dillon : Fixed another RST bug
90 * Alan Cox : Move to kernel side addressing changes.
91 * Alan Cox : Beginning work on TCP fastpathing
92 * (not yet usable)
93 * Arnt Gulbrandsen: Turbocharged tcp_check() routine.
94 * Alan Cox : TCP fast path debugging
95 * Alan Cox : Window clamping
96 * Michael Riepe : Bug in tcp_check()
97 * Matt Dillon : More TCP improvements and RST bug fixes
98 * Matt Dillon : Yet more small nasties remove from the
99 * TCP code (Be very nice to this man if
100 * tcp finally works 100%) 8)
101 * Alan Cox : BSD accept semantics.
102 * Alan Cox : Reset on closedown bug.
103 * Peter De Schrijver : ENOTCONN check missing in tcp_sendto().
104 * Michael Pall : Handle poll() after URG properly in
105 * all cases.
106 * Michael Pall : Undo the last fix in tcp_read_urg()
107 * (multi URG PUSH broke rlogin).
108 * Michael Pall : Fix the multi URG PUSH problem in
109 * tcp_readable(), poll() after URG
110 * works now.
111 * Michael Pall : recv(...,MSG_OOB) never blocks in the
112 * BSD api.
113 * Alan Cox : Changed the semantics of sk->socket to
114 * fix a race and a signal problem with
115 * accept() and async I/O.
116 * Alan Cox : Relaxed the rules on tcp_sendto().
117 * Yury Shevchuk : Really fixed accept() blocking problem.
118 * Craig I. Hagan : Allow for BSD compatible TIME_WAIT for
119 * clients/servers which listen in on
120 * fixed ports.
121 * Alan Cox : Cleaned the above up and shrank it to
122 * a sensible code size.
123 * Alan Cox : Self connect lockup fix.
124 * Alan Cox : No connect to multicast.
125 * Ross Biro : Close unaccepted children on master
126 * socket close.
127 * Alan Cox : Reset tracing code.
128 * Alan Cox : Spurious resets on shutdown.
129 * Alan Cox : Giant 15 minute/60 second timer error
130 * Alan Cox : Small whoops in polling before an
131 * accept.
132 * Alan Cox : Kept the state trace facility since
133 * it's handy for debugging.
134 * Alan Cox : More reset handler fixes.
135 * Alan Cox : Started rewriting the code based on
136 * the RFC's for other useful protocol
137 * references see: Comer, KA9Q NOS, and
138 * for a reference on the difference
139 * between specifications and how BSD
140 * works see the 4.4lite source.
141 * A.N.Kuznetsov : Don't time wait on completion of tidy
142 * close.
143 * Linus Torvalds : Fin/Shutdown & copied_seq changes.
144 * Linus Torvalds : Fixed BSD port reuse to work first syn
145 * Alan Cox : Reimplemented timers as per the RFC
146 * and using multiple timers for sanity.
147 * Alan Cox : Small bug fixes, and a lot of new
148 * comments.
149 * Alan Cox : Fixed dual reader crash by locking
150 * the buffers (much like datagram.c)
151 * Alan Cox : Fixed stuck sockets in probe. A probe
152 * now gets fed up of retrying without
153 * (even a no space) answer.
154 * Alan Cox : Extracted closing code better
155 * Alan Cox : Fixed the closing state machine to
156 * resemble the RFC.
157 * Alan Cox : More 'per spec' fixes.
158 * Jorge Cwik : Even faster checksumming.
159 * Alan Cox : tcp_data() doesn't ack illegal PSH
160 * only frames. At least one pc tcp stack
161 * generates them.
162 * Alan Cox : Cache last socket.
163 * Alan Cox : Per route irtt.
164 * Matt Day : poll()->select() match BSD precisely on error
165 * Alan Cox : New buffers
166 * Marc Tamsky : Various sk->prot->retransmits and
167 * sk->retransmits misupdating fixed.
168 * Fixed tcp_write_timeout: stuck close,
169 * and TCP syn retries gets used now.
170 * Mark Yarvis : In tcp_read_wakeup(), don't send an
171 * ack if state is TCP_CLOSED.
172 * Alan Cox : Look up device on a retransmit - routes may
173 * change. Doesn't yet cope with MSS shrink right
174 * but it's a start!
175 * Marc Tamsky : Closing in closing fixes.
176 * Mike Shaver : RFC1122 verifications.
177 * Alan Cox : rcv_saddr errors.
178 * Alan Cox : Block double connect().
179 * Alan Cox : Small hooks for enSKIP.
180 * Alexey Kuznetsov: Path MTU discovery.
181 * Alan Cox : Support soft errors.
182 * Alan Cox : Fix MTU discovery pathological case
183 * when the remote claims no mtu!
184 * Marc Tamsky : TCP_CLOSE fix.
185 * Colin (G3TNE) : Send a reset on syn ack replies in
186 * window but wrong (fixes NT lpd problems)
187 * Pedro Roque : Better TCP window handling, delayed ack.
188 * Joerg Reuter : No modification of locked buffers in
189 * tcp_do_retransmit()
190 * Eric Schenk : Changed receiver side silly window
191 * avoidance algorithm to BSD style
192 * algorithm. This doubles throughput
193 * against machines running Solaris,
194 * and seems to result in general
195 * improvement.
196 * Stefan Magdalinski : adjusted tcp_readable() to fix FIONREAD
197 * Willy Konynenberg : Transparent proxying support.
198 * Mike McLagan : Routing by source
199 * Keith Owens : Do proper merging with partial SKB's in
200 * tcp_do_sendmsg to avoid burstiness.
201 * Eric Schenk : Fix fast close down bug with
202 * shutdown() followed by close().
203 * Andi Kleen : Make poll agree with SIGIO
204 * Salvatore Sanfilippo : Support SO_LINGER with linger == 1 and
205 * lingertime == 0 (RFC 793 ABORT Call)
206 * Hirokazu Takahashi : Use copy_from_user() instead of
207 * csum_and_copy_from_user() if possible.
208 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209 * Description of States:
210 *
211 * TCP_SYN_SENT sent a connection request, waiting for ack
212 *
213 * TCP_SYN_RECV received a connection request, sent ack,
214 * waiting for final ack in three-way handshake.
215 *
216 * TCP_ESTABLISHED connection established
217 *
218 * TCP_FIN_WAIT1 our side has shutdown, waiting to complete
219 * transmission of remaining buffered data
220 *
221 * TCP_FIN_WAIT2 all buffered data sent, waiting for remote
222 * to shutdown
223 *
224 * TCP_CLOSING both sides have shutdown but we still have
225 * data we have to finish sending
226 *
227 * TCP_TIME_WAIT timeout to catch resent junk before entering
228 * closed, can only be entered from FIN_WAIT2
229 * or CLOSING. Required because the other end
230 * may not have gotten our last ACK causing it
231 * to retransmit the data packet (which we ignore)
232 *
233 * TCP_CLOSE_WAIT remote side has shutdown and is waiting for
234 * us to finish writing our data and to shutdown
235 * (we have to close() to move on to LAST_ACK)
236 *
237 * TCP_LAST_ACK out side has shutdown after remote has
238 * shutdown. There may still be data in our
239 * buffer that we have to finish sending
240 *
241 * TCP_CLOSE socket is finished
242 */
243
Joe Perchesafd465032012-03-12 07:03:32 +0000244#define pr_fmt(fmt) "TCP: " fmt
245
Herbert Xucf80e0e2016-01-24 21:20:23 +0800246#include <crypto/hash.h>
Ilpo Järvinen172589c2007-08-28 15:50:33 -0700247#include <linux/kernel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248#include <linux/module.h>
249#include <linux/types.h>
250#include <linux/fcntl.h>
251#include <linux/poll.h>
Eric Dumazet6e9250f2015-04-28 16:23:49 -0700252#include <linux/inet_diag.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253#include <linux/init.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254#include <linux/fs.h>
Jens Axboe9c55e012007-11-06 23:30:13 -0800255#include <linux/skbuff.h>
Andrew Morton81b23b42008-07-03 03:22:02 -0700256#include <linux/scatterlist.h>
Jens Axboe9c55e012007-11-06 23:30:13 -0800257#include <linux/splice.h>
258#include <linux/net.h>
259#include <linux/socket.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700260#include <linux/random.h>
Mike Rapoport57c8a662018-10-30 15:09:49 -0700261#include <linux/memblock.h>
Miquel van Smoorenburg57413eb2008-06-27 17:23:57 -0700262#include <linux/highmem.h>
263#include <linux/swap.h>
David S. Millerb8059ea2006-03-25 01:36:56 -0800264#include <linux/cache.h>
Herbert Xuf4c50d92006-06-22 03:02:40 -0700265#include <linux/err.h>
William Allen Simpsonda5c78c2009-12-02 18:12:09 +0000266#include <linux/time.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +0900267#include <linux/slab.h>
Mike Maloney98aaa912017-08-22 17:08:48 -0400268#include <linux/errqueue.h>
Ursula Braun60e2a772017-10-25 11:01:45 +0200269#include <linux/static_key.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700270
271#include <net/icmp.h>
Yuchung Chengcf60af02012-07-19 06:43:09 +0000272#include <net/inet_common.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700273#include <net/tcp.h>
274#include <net/xfrm.h>
275#include <net/ip.h>
Jens Axboe9c55e012007-11-06 23:30:13 -0800276#include <net/sock.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277
Linus Torvalds7c0f6ba2016-12-24 11:46:01 -0800278#include <linux/uaccess.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700279#include <asm/ioctls.h>
Eliezer Tamir076bb0c2013-07-10 17:13:17 +0300280#include <net/busy_poll.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -0700281
Eric Dumazetdd24c002008-11-25 21:17:14 -0800282struct percpu_counter tcp_orphan_count;
Arnaldo Carvalho de Melo0a5578c2005-08-09 20:11:41 -0700283EXPORT_SYMBOL_GPL(tcp_orphan_count);
284
Eric W. Biedermana4fe34b2013-10-19 16:25:36 -0700285long sysctl_tcp_mem[3] __read_mostly;
Eric W. Biedermana4fe34b2013-10-19 16:25:36 -0700286EXPORT_SYMBOL(sysctl_tcp_mem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287
Eric Dumazet8d987e52010-11-09 23:24:26 +0000288atomic_long_t tcp_memory_allocated; /* Current allocated memory. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289EXPORT_SYMBOL(tcp_memory_allocated);
Eric Dumazet17483762008-11-25 21:16:35 -0800290
Ursula Braun60e2a772017-10-25 11:01:45 +0200291#if IS_ENABLED(CONFIG_SMC)
292DEFINE_STATIC_KEY_FALSE(tcp_have_smc);
293EXPORT_SYMBOL(tcp_have_smc);
294#endif
295
Eric Dumazet17483762008-11-25 21:16:35 -0800296/*
297 * Current number of TCP sockets.
298 */
299struct percpu_counter tcp_sockets_allocated;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700300EXPORT_SYMBOL(tcp_sockets_allocated);
301
302/*
Jens Axboe9c55e012007-11-06 23:30:13 -0800303 * TCP splice context
304 */
305struct tcp_splice_state {
306 struct pipe_inode_info *pipe;
307 size_t len;
308 unsigned int flags;
309};
310
311/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700312 * Pressure flag: try to collapse.
313 * Technical note: it is used by multiple contexts non atomically.
Hideo Aoki3ab224b2007-12-31 00:11:19 -0800314 * All the __sk_mem_schedule() is of this nature: accounting
Linus Torvalds1da177e2005-04-16 15:20:36 -0700315 * is strict, actions are advisory and have some latency.
316 */
Eric Dumazet06044752017-06-07 13:29:12 -0700317unsigned long tcp_memory_pressure __read_mostly;
318EXPORT_SYMBOL_GPL(tcp_memory_pressure);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319
Eric Dumazet2e05fcae2019-06-15 13:19:55 -0700320DEFINE_STATIC_KEY_FALSE(tcp_rx_skb_cache_key);
321EXPORT_SYMBOL(tcp_rx_skb_cache_key);
322
323DEFINE_STATIC_KEY_FALSE(tcp_tx_skb_cache_key);
324
Pavel Emelyanov5c52ba12008-07-16 20:28:10 -0700325void tcp_enter_memory_pressure(struct sock *sk)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326{
Eric Dumazet06044752017-06-07 13:29:12 -0700327 unsigned long val;
328
Eric Dumazet1f142c12019-10-09 15:10:15 -0700329 if (READ_ONCE(tcp_memory_pressure))
Eric Dumazet06044752017-06-07 13:29:12 -0700330 return;
331 val = jiffies;
332
333 if (!val)
334 val--;
335 if (!cmpxchg(&tcp_memory_pressure, 0, val))
Pavel Emelyanov4e673442008-07-16 20:30:14 -0700336 NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMEMORYPRESSURES);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700337}
Eric Dumazet06044752017-06-07 13:29:12 -0700338EXPORT_SYMBOL_GPL(tcp_enter_memory_pressure);
339
340void tcp_leave_memory_pressure(struct sock *sk)
341{
342 unsigned long val;
343
Eric Dumazet1f142c12019-10-09 15:10:15 -0700344 if (!READ_ONCE(tcp_memory_pressure))
Eric Dumazet06044752017-06-07 13:29:12 -0700345 return;
346 val = xchg(&tcp_memory_pressure, 0);
347 if (val)
348 NET_ADD_STATS(sock_net(sk), LINUX_MIB_TCPMEMORYPRESSURESCHRONO,
349 jiffies_to_msecs(jiffies - val));
350}
351EXPORT_SYMBOL_GPL(tcp_leave_memory_pressure);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700352
Julian Anastasovb103cf32009-10-19 10:10:40 +0000353/* Convert seconds to retransmits based on initial and max timeout */
354static u8 secs_to_retrans(int seconds, int timeout, int rto_max)
355{
356 u8 res = 0;
357
358 if (seconds > 0) {
359 int period = timeout;
360
361 res = 1;
362 while (seconds > period && res < 255) {
363 res++;
364 timeout <<= 1;
365 if (timeout > rto_max)
366 timeout = rto_max;
367 period += timeout;
368 }
369 }
370 return res;
371}
372
373/* Convert retransmits to seconds based on initial and max timeout */
374static int retrans_to_secs(u8 retrans, int timeout, int rto_max)
375{
376 int period = 0;
377
378 if (retrans > 0) {
379 period = timeout;
380 while (--retrans) {
381 timeout <<= 1;
382 if (timeout > rto_max)
383 timeout = rto_max;
384 period += timeout;
385 }
386 }
387 return period;
388}
389
Wei Wang02635982017-07-28 10:28:20 -0700390static u64 tcp_compute_delivery_rate(const struct tcp_sock *tp)
391{
392 u32 rate = READ_ONCE(tp->rate_delivered);
393 u32 intv = READ_ONCE(tp->rate_interval_us);
394 u64 rate64 = 0;
395
396 if (rate && intv) {
397 rate64 = (u64)rate * tp->mss_cache * USEC_PER_SEC;
398 do_div(rate64, intv);
399 }
400 return rate64;
401}
402
Neal Cardwell900f65d2012-04-19 09:55:21 +0000403/* Address-family independent initialization for a tcp_sock.
404 *
405 * NOTE: A lot of things set to zero explicitly by call to
406 * sk_alloc() so need not be done here.
407 */
408void tcp_init_sock(struct sock *sk)
409{
410 struct inet_connection_sock *icsk = inet_csk(sk);
411 struct tcp_sock *tp = tcp_sk(sk);
412
Yaogong Wang9f5afea2016-09-07 14:49:28 -0700413 tp->out_of_order_queue = RB_ROOT;
Eric Dumazet75c119a2017-10-05 22:21:27 -0700414 sk->tcp_rtx_queue = RB_ROOT;
Neal Cardwell900f65d2012-04-19 09:55:21 +0000415 tcp_init_xmit_timers(sk);
Eric Dumazet46d3cea2012-07-11 05:50:31 +0000416 INIT_LIST_HEAD(&tp->tsq_node);
Eric Dumazete2080072017-10-04 12:59:58 -0700417 INIT_LIST_HEAD(&tp->tsorted_sent_queue);
Neal Cardwell900f65d2012-04-19 09:55:21 +0000418
419 icsk->icsk_rto = TCP_TIMEOUT_INIT;
Eric Dumazet740b0f12014-02-26 14:02:48 -0800420 tp->mdev_us = jiffies_to_usecs(TCP_TIMEOUT_INIT);
Eric Dumazetac9517f2017-05-16 14:00:13 -0700421 minmax_reset(&tp->rtt_min, tcp_jiffies32, ~0U);
Neal Cardwell900f65d2012-04-19 09:55:21 +0000422
423 /* So many TCP implementations out there (incorrectly) count the
424 * initial SYN frame in their delayed-ACK and congestion control
425 * algorithms that we must have the following bandaid to talk
426 * efficiently to them. -DaveM
427 */
428 tp->snd_cwnd = TCP_INIT_CWND;
429
Soheil Hassas Yeganehd7722e82016-09-19 23:39:15 -0400430 /* There's a bubble in the pipe until at least the first ACK. */
431 tp->app_limited = ~0U;
432
Neal Cardwell900f65d2012-04-19 09:55:21 +0000433 /* See draft-stevens-tcpca-spec-01 for discussion of the
434 * initialization of these values.
435 */
436 tp->snd_ssthresh = TCP_INFINITE_SSTHRESH;
437 tp->snd_cwnd_clamp = ~0;
438 tp->mss_cache = TCP_MSS_DEFAULT;
439
Nikolay Borisov1043e252016-02-03 09:46:52 +0200440 tp->reordering = sock_net(sk)->ipv4.sysctl_tcp_reordering;
Florian Westphal55d86942014-09-26 22:37:32 +0200441 tcp_assign_congestion_control(sk);
Neal Cardwell900f65d2012-04-19 09:55:21 +0000442
Andrey Vaginceaa1fe2013-02-11 05:50:17 +0000443 tp->tsoffset = 0;
Priyaranjan Jha1f255692017-11-03 16:38:48 -0700444 tp->rack.reo_wnd_steps = 1;
Andrey Vaginceaa1fe2013-02-11 05:50:17 +0000445
Neal Cardwell900f65d2012-04-19 09:55:21 +0000446 sk->sk_state = TCP_CLOSE;
447
448 sk->sk_write_space = sk_stream_write_space;
449 sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);
450
451 icsk->icsk_sync_mss = tcp_sync_mss;
452
Eric Dumazet356d1832017-11-07 00:29:28 -0800453 sk->sk_sndbuf = sock_net(sk)->ipv4.sysctl_tcp_wmem[1];
454 sk->sk_rcvbuf = sock_net(sk)->ipv4.sysctl_tcp_rmem[1];
Neal Cardwell900f65d2012-04-19 09:55:21 +0000455
Neal Cardwell900f65d2012-04-19 09:55:21 +0000456 sk_sockets_allocated_inc(sk);
Eric Dumazet0a6b2a12018-02-19 11:56:47 -0800457 sk->sk_route_forced_caps = NETIF_F_GSO;
Neal Cardwell900f65d2012-04-19 09:55:21 +0000458}
459EXPORT_SYMBOL(tcp_init_sock);
460
Eric Dumazet4e8cc222017-10-05 22:21:23 -0700461static void tcp_tx_timestamp(struct sock *sk, u16 tsflags)
Willem de Bruijn4ed2d762014-08-04 22:11:49 -0400462{
Eric Dumazet4e8cc222017-10-05 22:21:23 -0700463 struct sk_buff *skb = tcp_write_queue_tail(sk);
464
Soheil Hassas Yeganehad02c4f2017-01-04 11:19:34 -0500465 if (tsflags && skb) {
Willem de Bruijnf066e2b2014-08-06 15:09:44 -0400466 struct skb_shared_info *shinfo = skb_shinfo(skb);
Soheil Hassas Yeganeh6b084922016-04-02 23:08:08 -0400467 struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
Willem de Bruijn4ed2d762014-08-04 22:11:49 -0400468
Soheil Hassas Yeganehc14ac942016-04-02 23:08:12 -0400469 sock_tx_timestamp(sk, tsflags, &shinfo->tx_flags);
Soheil Hassas Yeganeh0a2cf202016-04-27 23:39:01 -0400470 if (tsflags & SOF_TIMESTAMPING_TX_ACK)
471 tcb->txstamp_ack = 1;
472 if (tsflags & SOF_TIMESTAMPING_TX_RECORD_MASK)
Willem de Bruijnf066e2b2014-08-06 15:09:44 -0400473 shinfo->tskey = TCP_SKB_CB(skb)->seq + skb->len - 1;
474 }
Willem de Bruijn4ed2d762014-08-04 22:11:49 -0400475}
476
John Fastabend8934ce22018-03-28 12:49:15 -0700477static inline bool tcp_stream_is_readable(const struct tcp_sock *tp,
478 int target, struct sock *sk)
479{
480 return (tp->rcv_nxt - tp->copied_seq >= target) ||
481 (sk->sk_prot->stream_memory_read ?
482 sk->sk_prot->stream_memory_read(sk) : false);
483}
484
Linus Torvalds1da177e2005-04-16 15:20:36 -0700485/*
Linus Torvaldsa11e1d42018-06-28 09:43:44 -0700486 * Wait for a TCP event.
487 *
488 * Note that we don't need to lock the socket, as the upper poll layers
489 * take care of normal races (between the test and the event) and we don't
490 * go look at any of the socket buffers directly.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700491 */
Linus Torvaldsa11e1d42018-06-28 09:43:44 -0700492__poll_t tcp_poll(struct file *file, struct socket *sock, poll_table *wait)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700493{
Linus Torvaldsa11e1d42018-06-28 09:43:44 -0700494 __poll_t mask;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700495 struct sock *sk = sock->sk;
Eric Dumazetcf533ea2011-10-21 05:22:42 -0400496 const struct tcp_sock *tp = tcp_sk(sk);
Eric Dumazet00fd38d2015-11-12 08:43:18 -0800497 int state;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700498
Karsten Graul89ab0662018-10-23 13:40:39 +0200499 sock_poll_wait(file, sock, wait);
Linus Torvaldsa11e1d42018-06-28 09:43:44 -0700500
Yafang Shao986ffdf2017-12-20 11:12:52 +0800501 state = inet_sk_state_load(sk);
Eric Dumazet00fd38d2015-11-12 08:43:18 -0800502 if (state == TCP_LISTEN)
Arnaldo Carvalho de Melodc40c7b2005-08-23 21:52:58 -0700503 return inet_csk_listen_poll(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700504
Linus Torvaldsa11e1d42018-06-28 09:43:44 -0700505 /* Socket is not locked. We are protected from async events
506 * by poll logic and correct handling of state changes
507 * made by other threads is impossible in any case.
508 */
509
510 mask = 0;
511
Linus Torvalds1da177e2005-04-16 15:20:36 -0700512 /*
Linus Torvaldsa9a08842018-02-11 14:34:03 -0800513 * EPOLLHUP is certainly not done right. But poll() doesn't
Linus Torvalds1da177e2005-04-16 15:20:36 -0700514 * have a notion of HUP in just one direction, and for a
515 * socket the read side is more interesting.
516 *
Linus Torvaldsa9a08842018-02-11 14:34:03 -0800517 * Some poll() documentation says that EPOLLHUP is incompatible
518 * with the EPOLLOUT/POLLWR flags, so somebody should check this
Linus Torvalds1da177e2005-04-16 15:20:36 -0700519 * all. But careful, it tends to be safer to return too many
520 * bits than too few, and you can easily break real applications
521 * if you don't tell them that something has hung up!
522 *
523 * Check-me.
524 *
Linus Torvaldsa9a08842018-02-11 14:34:03 -0800525 * Check number 1. EPOLLHUP is _UNMASKABLE_ event (see UNIX98 and
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526 * our fs/select.c). It means that after we received EOF,
527 * poll always returns immediately, making impossible poll() on write()
Linus Torvaldsa9a08842018-02-11 14:34:03 -0800528 * in state CLOSE_WAIT. One solution is evident --- to set EPOLLHUP
Linus Torvalds1da177e2005-04-16 15:20:36 -0700529 * if and only if shutdown has been made in both directions.
530 * Actually, it is interesting to look how Solaris and DUX
Linus Torvaldsa9a08842018-02-11 14:34:03 -0800531 * solve this dilemma. I would prefer, if EPOLLHUP were maskable,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700532 * then we could set it on SND_SHUTDOWN. BTW examples given
533 * in Stevens' books assume exactly this behaviour, it explains
Linus Torvaldsa9a08842018-02-11 14:34:03 -0800534 * why EPOLLHUP is incompatible with EPOLLOUT. --ANK
Linus Torvalds1da177e2005-04-16 15:20:36 -0700535 *
536 * NOTE. Check for TCP_CLOSE is added. The goal is to prevent
537 * blocking on fresh not-connected or disconnected socket. --ANK
538 */
Eric Dumazet00fd38d2015-11-12 08:43:18 -0800539 if (sk->sk_shutdown == SHUTDOWN_MASK || state == TCP_CLOSE)
Linus Torvaldsa9a08842018-02-11 14:34:03 -0800540 mask |= EPOLLHUP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700541 if (sk->sk_shutdown & RCV_SHUTDOWN)
Linus Torvaldsa9a08842018-02-11 14:34:03 -0800542 mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700543
Jerry Chu83368862012-08-31 12:29:12 +0000544 /* Connected or passive Fast Open socket? */
Eric Dumazet00fd38d2015-11-12 08:43:18 -0800545 if (state != TCP_SYN_SENT &&
546 (state != TCP_SYN_RECV || tp->fastopen_rsk)) {
David S. Millerc7004482008-10-06 10:43:54 -0700547 int target = sock_rcvlowat(sk, 0, INT_MAX);
548
549 if (tp->urg_seq == tp->copied_seq &&
550 !sock_flag(sk, SOCK_URGINLINE) &&
551 tp->urg_data)
Alexandra Kossovskyb634f872010-03-18 20:29:24 -0700552 target++;
David S. Millerc7004482008-10-06 10:43:54 -0700553
John Fastabend8934ce22018-03-28 12:49:15 -0700554 if (tcp_stream_is_readable(tp, target, sk))
Linus Torvaldsa9a08842018-02-11 14:34:03 -0800555 mask |= EPOLLIN | EPOLLRDNORM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556
557 if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
Eric Dumazet64dc6132013-07-22 20:26:31 -0700558 if (sk_stream_is_writeable(sk)) {
Linus Torvaldsa9a08842018-02-11 14:34:03 -0800559 mask |= EPOLLOUT | EPOLLWRNORM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560 } else { /* send SIGIO later */
Eric Dumazet9cd3e072015-11-29 20:03:10 -0800561 sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700562 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
563
564 /* Race breaker. If space is freed after
565 * wspace test but before the flags are set,
jbaron@akamai.com3c715122015-04-20 20:05:07 +0000566 * IO signal will be lost. Memory barrier
567 * pairs with the input side.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700568 */
jbaron@akamai.com3c715122015-04-20 20:05:07 +0000569 smp_mb__after_atomic();
Eric Dumazet64dc6132013-07-22 20:26:31 -0700570 if (sk_stream_is_writeable(sk))
Linus Torvaldsa9a08842018-02-11 14:34:03 -0800571 mask |= EPOLLOUT | EPOLLWRNORM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700572 }
KOSAKI Motohirod84ba632010-08-24 16:05:48 +0000573 } else
Linus Torvaldsa9a08842018-02-11 14:34:03 -0800574 mask |= EPOLLOUT | EPOLLWRNORM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700575
576 if (tp->urg_data & TCP_URG_VALID)
Linus Torvaldsa9a08842018-02-11 14:34:03 -0800577 mask |= EPOLLPRI;
Davide Carattid68be712017-04-26 19:07:35 +0200578 } else if (state == TCP_SYN_SENT && inet_sk(sk)->defer_connect) {
Wei Wang19f6d3f2017-01-23 10:59:22 -0800579 /* Active TCP fastopen socket with defer_connect
Linus Torvaldsa9a08842018-02-11 14:34:03 -0800580 * Return EPOLLOUT so application can call write()
Wei Wang19f6d3f2017-01-23 10:59:22 -0800581 * in order for kernel to generate SYN+data
582 */
Linus Torvaldsa9a08842018-02-11 14:34:03 -0800583 mask |= EPOLLOUT | EPOLLWRNORM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584 }
Tom Marshalla4d25802010-09-20 15:42:05 -0700585 /* This barrier is coupled with smp_wmb() in tcp_reset() */
586 smp_rmb();
Willem de Bruijn4ed2d762014-08-04 22:11:49 -0400587 if (sk->sk_err || !skb_queue_empty(&sk->sk_error_queue))
Linus Torvaldsa9a08842018-02-11 14:34:03 -0800588 mask |= EPOLLERR;
Tom Marshalla4d25802010-09-20 15:42:05 -0700589
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590 return mask;
591}
Linus Torvaldsa11e1d42018-06-28 09:43:44 -0700592EXPORT_SYMBOL(tcp_poll);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700593
594int tcp_ioctl(struct sock *sk, int cmd, unsigned long arg)
595{
596 struct tcp_sock *tp = tcp_sk(sk);
597 int answ;
Eric Dumazet0e71c552012-10-21 20:06:56 +0000598 bool slow;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700599
600 switch (cmd) {
601 case SIOCINQ:
602 if (sk->sk_state == TCP_LISTEN)
603 return -EINVAL;
604
Eric Dumazet0e71c552012-10-21 20:06:56 +0000605 slow = lock_sock_fast(sk);
Tom Herbert473bd232016-03-07 14:11:05 -0800606 answ = tcp_inq(sk);
Eric Dumazet0e71c552012-10-21 20:06:56 +0000607 unlock_sock_fast(sk, slow);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700608 break;
609 case SIOCATMARK:
610 answ = tp->urg_data && tp->urg_seq == tp->copied_seq;
611 break;
612 case SIOCOUTQ:
613 if (sk->sk_state == TCP_LISTEN)
614 return -EINVAL;
615
616 if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV))
617 answ = 0;
618 else
619 answ = tp->write_seq - tp->snd_una;
620 break;
Mario Schuknecht2f4e1b32011-03-09 14:08:09 -0800621 case SIOCOUTQNSD:
622 if (sk->sk_state == TCP_LISTEN)
623 return -EINVAL;
624
625 if ((1 << sk->sk_state) & (TCPF_SYN_SENT | TCPF_SYN_RECV))
626 answ = 0;
627 else
628 answ = tp->write_seq - tp->snd_nxt;
629 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700630 default:
631 return -ENOIOCTLCMD;
Stephen Hemminger3ff50b72007-04-20 17:09:22 -0700632 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700633
634 return put_user(answ, (int __user *)arg);
635}
Eric Dumazet4bc2f182010-07-09 21:22:10 +0000636EXPORT_SYMBOL(tcp_ioctl);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700637
Linus Torvalds1da177e2005-04-16 15:20:36 -0700638static inline void tcp_mark_push(struct tcp_sock *tp, struct sk_buff *skb)
639{
Eric Dumazet4de075e2011-09-27 13:25:05 -0400640 TCP_SKB_CB(skb)->tcp_flags |= TCPHDR_PSH;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700641 tp->pushed_seq = tp->write_seq;
642}
643
Eric Dumazeta2a385d2012-05-16 23:15:34 +0000644static inline bool forced_push(const struct tcp_sock *tp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700645{
646 return after(tp->write_seq, tp->pushed_seq + (tp->max_window >> 1));
647}
648
Eric Dumazetf4a775d2014-09-22 16:29:32 -0700649static void skb_entail(struct sock *sk, struct sk_buff *skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700650{
Ilpo Järvinen9e412ba2007-04-20 22:18:02 -0700651 struct tcp_sock *tp = tcp_sk(sk);
Arnaldo Carvalho de Melo352d4802006-11-17 19:59:12 -0200652 struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
653
654 skb->csum = 0;
655 tcb->seq = tcb->end_seq = tp->write_seq;
Eric Dumazet4de075e2011-09-27 13:25:05 -0400656 tcb->tcp_flags = TCPHDR_ACK;
Arnaldo Carvalho de Melo352d4802006-11-17 19:59:12 -0200657 tcb->sacked = 0;
Eric Dumazetf4a775d2014-09-22 16:29:32 -0700658 __skb_header_release(skb);
David S. Millerfe067e82007-03-07 12:12:44 -0800659 tcp_add_write_queue_tail(sk, skb);
Hideo Aoki3ab224b2007-12-31 00:11:19 -0800660 sk->sk_wmem_queued += skb->truesize;
661 sk_mem_charge(sk, skb->truesize);
David S. Miller89ebd192005-08-23 10:13:06 -0700662 if (tp->nonagle & TCP_NAGLE_PUSH)
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +0900663 tp->nonagle &= ~TCP_NAGLE_PUSH;
Eric Dumazet6f021c62015-08-21 12:30:00 -0700664
665 tcp_slow_start_after_idle_check(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666}
667
Krishna Kumarafeca342009-12-10 07:16:52 +0000668static inline void tcp_mark_urg(struct tcp_sock *tp, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700669{
Ilpo Järvinen33f5f572008-10-07 14:43:06 -0700670 if (flags & MSG_OOB)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700671 tp->snd_up = tp->write_seq;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700672}
673
Eric Dumazetf54b3112013-12-05 22:36:05 -0800674/* If a not yet filled skb is pushed, do not send it if
Eric Dumazeta181ceb2013-12-17 09:58:30 -0800675 * we have data packets in Qdisc or NIC queues :
Eric Dumazetf54b3112013-12-05 22:36:05 -0800676 * Because TX completion will happen shortly, it gives a chance
677 * to coalesce future sendmsg() payload into this skb, without
678 * need for a timer, and with no latency trade off.
679 * As packets containing data payload have a bigger truesize
Eric Dumazeta181ceb2013-12-17 09:58:30 -0800680 * than pure acks (dataless) packets, the last checks prevent
681 * autocorking if we only have an ACK in Qdisc/NIC queues,
682 * or if TX completion was delayed after we processed ACK packet.
Eric Dumazetf54b3112013-12-05 22:36:05 -0800683 */
684static bool tcp_should_autocork(struct sock *sk, struct sk_buff *skb,
685 int size_goal)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686{
Eric Dumazetf54b3112013-12-05 22:36:05 -0800687 return skb->len < size_goal &&
Eric Dumazet790f00e2017-10-27 07:47:29 -0700688 sock_net(sk)->ipv4.sysctl_tcp_autocorking &&
Eric Dumazet114f39f2018-05-02 20:25:13 -0700689 !tcp_rtx_queue_empty(sk) &&
Reshetova, Elena14afee42017-06-30 13:08:00 +0300690 refcount_read(&sk->sk_wmem_alloc) > skb->truesize;
Eric Dumazetf54b3112013-12-05 22:36:05 -0800691}
Krishna Kumarafeca342009-12-10 07:16:52 +0000692
Eric Dumazetf54b3112013-12-05 22:36:05 -0800693static void tcp_push(struct sock *sk, int flags, int mss_now,
694 int nonagle, int size_goal)
695{
696 struct tcp_sock *tp = tcp_sk(sk);
697 struct sk_buff *skb;
Krishna Kumarafeca342009-12-10 07:16:52 +0000698
Eric Dumazetf54b3112013-12-05 22:36:05 -0800699 skb = tcp_write_queue_tail(sk);
Eric Dumazet75c119a2017-10-05 22:21:27 -0700700 if (!skb)
701 return;
Eric Dumazetf54b3112013-12-05 22:36:05 -0800702 if (!(flags & MSG_MORE) || forced_push(tp))
703 tcp_mark_push(tp, skb);
704
705 tcp_mark_urg(tp, flags);
706
707 if (tcp_should_autocork(sk, skb, size_goal)) {
708
709 /* avoid atomic op if TSQ_THROTTLED bit is already set */
Eric Dumazet7aa54702016-12-03 11:14:57 -0800710 if (!test_bit(TSQ_THROTTLED, &sk->sk_tsq_flags)) {
Eric Dumazetf54b3112013-12-05 22:36:05 -0800711 NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPAUTOCORKING);
Eric Dumazet7aa54702016-12-03 11:14:57 -0800712 set_bit(TSQ_THROTTLED, &sk->sk_tsq_flags);
Eric Dumazetf54b3112013-12-05 22:36:05 -0800713 }
Eric Dumazeta181ceb2013-12-17 09:58:30 -0800714 /* It is possible TX completion already happened
715 * before we set TSQ_THROTTLED.
716 */
Reshetova, Elena14afee42017-06-30 13:08:00 +0300717 if (refcount_read(&sk->sk_wmem_alloc) > skb->truesize)
Eric Dumazeta181ceb2013-12-17 09:58:30 -0800718 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700719 }
Eric Dumazetf54b3112013-12-05 22:36:05 -0800720
721 if (flags & MSG_MORE)
722 nonagle = TCP_NAGLE_CORK;
723
724 __tcp_push_pending_frames(sk, mss_now, nonagle);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700725}
726
Adrian Bunk6ff77512007-11-06 23:32:26 -0800727static int tcp_splice_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
728 unsigned int offset, size_t len)
Jens Axboe9c55e012007-11-06 23:30:13 -0800729{
730 struct tcp_splice_state *tss = rd_desc->arg.data;
Willy Tarreau33966dd02009-01-13 16:04:36 -0800731 int ret;
Jens Axboe9c55e012007-11-06 23:30:13 -0800732
Hannes Frederic Sowaa60e3cc2015-05-21 17:00:00 +0200733 ret = skb_splice_bits(skb, skb->sk, offset, tss->pipe,
Al Viro25869262016-09-17 21:02:10 -0400734 min(rd_desc->count, len), tss->flags);
Willy Tarreau33966dd02009-01-13 16:04:36 -0800735 if (ret > 0)
736 rd_desc->count -= ret;
737 return ret;
Jens Axboe9c55e012007-11-06 23:30:13 -0800738}
739
740static int __tcp_splice_read(struct sock *sk, struct tcp_splice_state *tss)
741{
742 /* Store TCP splice context information in read_descriptor_t. */
743 read_descriptor_t rd_desc = {
744 .arg.data = tss,
Willy Tarreau33966dd02009-01-13 16:04:36 -0800745 .count = tss->len,
Jens Axboe9c55e012007-11-06 23:30:13 -0800746 };
747
748 return tcp_read_sock(sk, &rd_desc, tcp_splice_data_recv);
749}
750
751/**
752 * tcp_splice_read - splice data from TCP socket to a pipe
753 * @sock: socket to splice from
754 * @ppos: position (not valid)
755 * @pipe: pipe to splice to
756 * @len: number of bytes to splice
757 * @flags: splice modifier flags
758 *
759 * Description:
760 * Will read pages from given socket and fill them into a pipe.
761 *
762 **/
763ssize_t tcp_splice_read(struct socket *sock, loff_t *ppos,
764 struct pipe_inode_info *pipe, size_t len,
765 unsigned int flags)
766{
767 struct sock *sk = sock->sk;
768 struct tcp_splice_state tss = {
769 .pipe = pipe,
770 .len = len,
771 .flags = flags,
772 };
773 long timeo;
774 ssize_t spliced;
775 int ret;
776
Changli Gao3a047bf2010-07-12 21:00:12 +0000777 sock_rps_record_flow(sk);
Jens Axboe9c55e012007-11-06 23:30:13 -0800778 /*
779 * We can't seek on a socket input
780 */
781 if (unlikely(*ppos))
782 return -ESPIPE;
783
784 ret = spliced = 0;
785
786 lock_sock(sk);
787
Eric Dumazet42324c62009-10-01 15:26:00 -0700788 timeo = sock_rcvtimeo(sk, sock->file->f_flags & O_NONBLOCK);
Jens Axboe9c55e012007-11-06 23:30:13 -0800789 while (tss.len) {
790 ret = __tcp_splice_read(sk, &tss);
791 if (ret < 0)
792 break;
793 else if (!ret) {
794 if (spliced)
795 break;
Jens Axboe9c55e012007-11-06 23:30:13 -0800796 if (sock_flag(sk, SOCK_DONE))
797 break;
798 if (sk->sk_err) {
799 ret = sock_error(sk);
800 break;
801 }
802 if (sk->sk_shutdown & RCV_SHUTDOWN)
803 break;
804 if (sk->sk_state == TCP_CLOSE) {
805 /*
806 * This occurs when user tries to read
807 * from never connected socket.
808 */
Eric Dumazetc47078d2018-07-07 23:15:56 -0700809 ret = -ENOTCONN;
Jens Axboe9c55e012007-11-06 23:30:13 -0800810 break;
811 }
812 if (!timeo) {
813 ret = -EAGAIN;
814 break;
815 }
Eric Dumazetccf7abb2017-02-03 14:59:38 -0800816 /* if __tcp_splice_read() got nothing while we have
817 * an skb in receive queue, we do not want to loop.
818 * This might happen with URG data.
819 */
820 if (!skb_queue_empty(&sk->sk_receive_queue))
821 break;
Sabrina Dubrocadfbafc92015-07-24 18:19:25 +0200822 sk_wait_data(sk, &timeo, NULL);
Jens Axboe9c55e012007-11-06 23:30:13 -0800823 if (signal_pending(current)) {
824 ret = sock_intr_errno(timeo);
825 break;
826 }
827 continue;
828 }
829 tss.len -= ret;
830 spliced += ret;
831
Willy Tarreau33966dd02009-01-13 16:04:36 -0800832 if (!timeo)
833 break;
Jens Axboe9c55e012007-11-06 23:30:13 -0800834 release_sock(sk);
835 lock_sock(sk);
836
837 if (sk->sk_err || sk->sk_state == TCP_CLOSE ||
Willy Tarreau33966dd02009-01-13 16:04:36 -0800838 (sk->sk_shutdown & RCV_SHUTDOWN) ||
Jens Axboe9c55e012007-11-06 23:30:13 -0800839 signal_pending(current))
840 break;
841 }
842
843 release_sock(sk);
844
845 if (spliced)
846 return spliced;
847
848 return ret;
849}
Eric Dumazet4bc2f182010-07-09 21:22:10 +0000850EXPORT_SYMBOL(tcp_splice_read);
Jens Axboe9c55e012007-11-06 23:30:13 -0800851
Eric Dumazeteb934472015-05-19 13:26:55 -0700852struct sk_buff *sk_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp,
853 bool force_schedule)
Pavel Emelyanovf561d0f2007-11-29 20:28:50 +1100854{
855 struct sk_buff *skb;
856
Eric Dumazet4f661542019-03-26 08:34:55 -0700857 if (likely(!size)) {
858 skb = sk->sk_tx_skb_cache;
Eric Dumazet858f5012019-05-15 09:10:15 -0700859 if (skb) {
Eric Dumazetd7cc399e2019-04-19 16:02:03 -0700860 skb->truesize = SKB_TRUESIZE(skb_end_offset(skb));
Eric Dumazet472c2e02019-03-22 08:56:39 -0700861 sk->sk_tx_skb_cache = NULL;
862 pskb_trim(skb, 0);
863 INIT_LIST_HEAD(&skb->tcp_tsorted_anchor);
Eric Dumazeteb70a1a2019-03-29 12:46:17 -0700864 skb_shinfo(skb)->tx_flags = 0;
865 memset(TCP_SKB_CB(skb), 0, sizeof(struct tcp_skb_cb));
Eric Dumazet472c2e02019-03-22 08:56:39 -0700866 return skb;
867 }
868 }
Pavel Emelyanovf561d0f2007-11-29 20:28:50 +1100869 /* The TCP header must be at least 32-bit aligned. */
870 size = ALIGN(size, 4);
871
Eric Dumazet8e4d9802015-05-15 12:39:28 -0700872 if (unlikely(tcp_under_memory_pressure(sk)))
873 sk_mem_reclaim_partial(sk);
874
Pavel Emelyanovf561d0f2007-11-29 20:28:50 +1100875 skb = alloc_skb_fclone(size + sk->sk_prot->max_header, gfp);
Eric Dumazet8e4d9802015-05-15 12:39:28 -0700876 if (likely(skb)) {
Eric Dumazeteb934472015-05-19 13:26:55 -0700877 bool mem_scheduled;
Eric Dumazet8e4d9802015-05-15 12:39:28 -0700878
Eric Dumazeteb934472015-05-19 13:26:55 -0700879 if (force_schedule) {
880 mem_scheduled = true;
Eric Dumazet8e4d9802015-05-15 12:39:28 -0700881 sk_forced_mem_schedule(sk, skb->truesize);
882 } else {
Eric Dumazeteb934472015-05-19 13:26:55 -0700883 mem_scheduled = sk_wmem_schedule(sk, skb->truesize);
Eric Dumazet8e4d9802015-05-15 12:39:28 -0700884 }
Eric Dumazeteb934472015-05-19 13:26:55 -0700885 if (likely(mem_scheduled)) {
Eric Dumazeta21d4572012-04-10 20:30:48 +0000886 skb_reserve(skb, sk->sk_prot->max_header);
Pavel Emelyanovf561d0f2007-11-29 20:28:50 +1100887 /*
888 * Make sure that we have exactly size bytes
889 * available to the caller, no more, no less.
890 */
Eric Dumazet16fad692013-03-14 05:40:32 +0000891 skb->reserved_tailroom = skb->end - skb->tail - size;
Eric Dumazete2080072017-10-04 12:59:58 -0700892 INIT_LIST_HEAD(&skb->tcp_tsorted_anchor);
Pavel Emelyanovf561d0f2007-11-29 20:28:50 +1100893 return skb;
894 }
895 __kfree_skb(skb);
896 } else {
Pavel Emelyanov5c52ba12008-07-16 20:28:10 -0700897 sk->sk_prot->enter_memory_pressure(sk);
Pavel Emelyanovf561d0f2007-11-29 20:28:50 +1100898 sk_stream_moderate_sndbuf(sk);
899 }
900 return NULL;
901}
902
Ilpo Järvinen0c54b852009-03-14 14:23:05 +0000903static unsigned int tcp_xmit_size_goal(struct sock *sk, u32 mss_now,
904 int large_allowed)
905{
906 struct tcp_sock *tp = tcp_sk(sk);
Eric Dumazet6c09fa02015-03-05 08:03:06 -0800907 u32 new_size_goal, size_goal;
Ilpo Järvinen0c54b852009-03-14 14:23:05 +0000908
Eric Dumazet74d4a8f2018-02-19 11:56:48 -0800909 if (!large_allowed)
Eric Dumazet605ad7f2014-12-07 12:22:18 -0800910 return mss_now;
Ilpo Järvinen0c54b852009-03-14 14:23:05 +0000911
Eric Dumazet6c09fa02015-03-05 08:03:06 -0800912 /* Note : tcp_tso_autosize() will eventually split this later */
913 new_size_goal = sk->sk_gso_max_size - 1 - MAX_TCP_HEADER;
Eric Dumazet605ad7f2014-12-07 12:22:18 -0800914 new_size_goal = tcp_bound_to_half_wnd(tp, new_size_goal);
Eric Dumazet95bd09e2013-08-27 05:46:32 -0700915
Eric Dumazet605ad7f2014-12-07 12:22:18 -0800916 /* We try hard to avoid divides here */
917 size_goal = tp->gso_segs * mss_now;
918 if (unlikely(new_size_goal < size_goal ||
919 new_size_goal >= size_goal + mss_now)) {
920 tp->gso_segs = min_t(u16, new_size_goal / mss_now,
921 sk->sk_gso_max_segs);
922 size_goal = tp->gso_segs * mss_now;
Ilpo Järvinen0c54b852009-03-14 14:23:05 +0000923 }
924
Eric Dumazet605ad7f2014-12-07 12:22:18 -0800925 return max(size_goal, mss_now);
Ilpo Järvinen0c54b852009-03-14 14:23:05 +0000926}
927
928static int tcp_send_mss(struct sock *sk, int *size_goal, int flags)
929{
930 int mss_now;
931
932 mss_now = tcp_current_mss(sk);
933 *size_goal = tcp_xmit_size_goal(sk, mss_now, !(flags & MSG_OOB));
934
935 return mss_now;
936}
937
Eric Dumazetfdfc5c82019-08-26 09:19:15 -0700938/* In some cases, both sendpage() and sendmsg() could have added
939 * an skb to the write queue, but failed adding payload on it.
940 * We need to remove it to consume less memory, but more
941 * importantly be able to generate EPOLLOUT for Edge Trigger epoll()
942 * users.
943 */
944static void tcp_remove_empty_skb(struct sock *sk, struct sk_buff *skb)
945{
946 if (skb && !skb->len) {
947 tcp_unlink_write_queue(skb, sk);
948 if (tcp_write_queue_empty(sk))
949 tcp_chrono_stop(sk, TCP_CHRONO_BUSY);
950 sk_wmem_free_skb(sk, skb);
951 }
952}
953
Dave Watsone3b56162017-06-14 11:37:26 -0700954ssize_t do_tcp_sendpages(struct sock *sk, struct page *page, int offset,
955 size_t size, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700956{
957 struct tcp_sock *tp = tcp_sk(sk);
David S. Millerc1b4a7e2005-07-05 15:24:38 -0700958 int mss_now, size_goal;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700959 int err;
960 ssize_t copied;
961 long timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
962
Vasily Averina10674b2019-03-06 14:10:22 +0300963 if (IS_ENABLED(CONFIG_DEBUG_VM) &&
964 WARN_ONCE(PageSlab(page), "page must not be a Slab one"))
965 return -EINVAL;
966
Jerry Chu83368862012-08-31 12:29:12 +0000967 /* Wait for a connection to finish. One exception is TCP Fast Open
968 * (passive side) where data is allowed to be sent before a connection
969 * is fully established.
970 */
971 if (((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) &&
972 !tcp_passive_fastopen(sk)) {
Yuvaraja Mariappan686a5622015-10-06 10:53:29 -0700973 err = sk_stream_wait_connect(sk, &timeo);
974 if (err != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700975 goto out_err;
Jerry Chu83368862012-08-31 12:29:12 +0000976 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700977
Eric Dumazet9cd3e072015-11-29 20:03:10 -0800978 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700979
Ilpo Järvinen0c54b852009-03-14 14:23:05 +0000980 mss_now = tcp_send_mss(sk, &size_goal, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700981 copied = 0;
982
983 err = -EPIPE;
984 if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
Ilpo Järvinen0d6a7752009-02-28 04:44:41 +0000985 goto out_err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700986
Eric Dumazet64022d02012-12-01 13:07:02 +0000987 while (size > 0) {
David S. Millerfe067e82007-03-07 12:12:44 -0800988 struct sk_buff *skb = tcp_write_queue_tail(sk);
Eric Dumazet38ba0a62012-04-23 17:48:27 +0000989 int copy, i;
Eric Dumazet38ba0a62012-04-23 17:48:27 +0000990 bool can_coalesce;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700991
Eric Dumazet75c119a2017-10-05 22:21:27 -0700992 if (!skb || (copy = size_goal - skb->len) <= 0 ||
Martin KaFai Lauc134ecb2016-04-25 14:44:48 -0700993 !tcp_skb_can_collapse_to(skb)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700994new_segment:
995 if (!sk_stream_memory_free(sk))
996 goto wait_for_sndbuf;
997
Eric Dumazeteb934472015-05-19 13:26:55 -0700998 skb = sk_stream_alloc_skb(sk, 0, sk->sk_allocation,
Eric Dumazet75c119a2017-10-05 22:21:27 -0700999 tcp_rtx_and_write_queues_empty(sk));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001000 if (!skb)
1001 goto wait_for_memory;
1002
Jakub Kicinski41477662019-08-07 17:03:59 -07001003#ifdef CONFIG_TLS_DEVICE
1004 skb->decrypted = !!(flags & MSG_SENDPAGE_DECRYPTED);
1005#endif
Ilpo Järvinen9e412ba2007-04-20 22:18:02 -07001006 skb_entail(sk, skb);
David S. Millerc1b4a7e2005-07-05 15:24:38 -07001007 copy = size_goal;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001008 }
1009
1010 if (copy > size)
1011 copy = size;
1012
1013 i = skb_shinfo(skb)->nr_frags;
1014 can_coalesce = skb_can_coalesce(skb, i, page, offset);
Hans Westgaard Ry5f74f82e2016-02-03 09:26:57 +01001015 if (!can_coalesce && i >= sysctl_max_skb_frags) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001016 tcp_mark_push(tp, skb);
1017 goto new_segment;
1018 }
Hideo Aoki3ab224b2007-12-31 00:11:19 -08001019 if (!sk_wmem_schedule(sk, copy))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001020 goto wait_for_memory;
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09001021
Linus Torvalds1da177e2005-04-16 15:20:36 -07001022 if (can_coalesce) {
Eric Dumazet9e903e02011-10-18 21:00:24 +00001023 skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001024 } else {
1025 get_page(page);
1026 skb_fill_page_desc(skb, i, page, offset, copy);
1027 }
John Fastabend312fc2b2018-03-18 12:57:00 -07001028
1029 if (!(flags & MSG_NO_SHARED_FRAGS))
1030 skb_shinfo(skb)->tx_flags |= SKBTX_SHARED_FRAG;
Eric Dumazetcef401d2013-01-25 20:34:37 +00001031
Linus Torvalds1da177e2005-04-16 15:20:36 -07001032 skb->len += copy;
1033 skb->data_len += copy;
1034 skb->truesize += copy;
1035 sk->sk_wmem_queued += copy;
Hideo Aoki3ab224b2007-12-31 00:11:19 -08001036 sk_mem_charge(sk, copy);
Patrick McHardy84fa7932006-08-29 16:44:56 -07001037 skb->ip_summed = CHECKSUM_PARTIAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001038 tp->write_seq += copy;
1039 TCP_SKB_CB(skb)->end_seq += copy;
Eric Dumazetcd7d8492014-09-24 04:11:22 -07001040 tcp_skb_pcount_set(skb, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001041
1042 if (!copied)
Eric Dumazet4de075e2011-09-27 13:25:05 -04001043 TCP_SKB_CB(skb)->tcp_flags &= ~TCPHDR_PSH;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001044
1045 copied += copy;
Eric Dumazet64022d02012-12-01 13:07:02 +00001046 offset += copy;
Yuvaraja Mariappan686a5622015-10-06 10:53:29 -07001047 size -= copy;
Soheil Hassas Yeganehad02c4f2017-01-04 11:19:34 -05001048 if (!size)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001049 goto out;
1050
Herbert Xu69d15062008-03-22 15:47:05 -07001051 if (skb->len < size_goal || (flags & MSG_OOB))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001052 continue;
1053
1054 if (forced_push(tp)) {
1055 tcp_mark_push(tp, skb);
Ilpo Järvinen9e412ba2007-04-20 22:18:02 -07001056 __tcp_push_pending_frames(sk, mss_now, TCP_NAGLE_PUSH);
David S. Millerfe067e82007-03-07 12:12:44 -08001057 } else if (skb == tcp_send_head(sk))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001058 tcp_push_one(sk, mss_now);
1059 continue;
1060
1061wait_for_sndbuf:
1062 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1063wait_for_memory:
Eric Dumazetf54b3112013-12-05 22:36:05 -08001064 tcp_push(sk, flags & ~MSG_MORE, mss_now,
1065 TCP_NAGLE_PUSH, size_goal);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001066
Yuvaraja Mariappan686a5622015-10-06 10:53:29 -07001067 err = sk_stream_wait_memory(sk, &timeo);
1068 if (err != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001069 goto do_error;
1070
Ilpo Järvinen0c54b852009-03-14 14:23:05 +00001071 mss_now = tcp_send_mss(sk, &size_goal, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001072 }
1073
1074out:
Soheil Hassas Yeganehad02c4f2017-01-04 11:19:34 -05001075 if (copied) {
Eric Dumazet4e8cc222017-10-05 22:21:23 -07001076 tcp_tx_timestamp(sk, sk->sk_tsflags);
Soheil Hassas Yeganehad02c4f2017-01-04 11:19:34 -05001077 if (!(flags & MSG_SENDPAGE_NOTLAST))
1078 tcp_push(sk, flags, mss_now, tp->nonagle, size_goal);
1079 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001080 return copied;
1081
1082do_error:
Eric Dumazetfdfc5c82019-08-26 09:19:15 -07001083 tcp_remove_empty_skb(sk, tcp_write_queue_tail(sk));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001084 if (copied)
1085 goto out;
1086out_err:
Jason Baronce5ec442015-05-20 15:52:53 +00001087 /* make sure we wake any epoll edge trigger waiter */
Francis Yanb0f71bd2016-11-27 23:07:16 -08001088 if (unlikely(skb_queue_len(&sk->sk_write_queue) == 0 &&
1089 err == -EAGAIN)) {
Jason Baronce5ec442015-05-20 15:52:53 +00001090 sk->sk_write_space(sk);
Francis Yanb0f71bd2016-11-27 23:07:16 -08001091 tcp_chrono_stop(sk, TCP_CHRONO_SNDBUF_LIMITED);
1092 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001093 return sk_stream_error(sk, flags, err);
1094}
Dave Watsone3b56162017-06-14 11:37:26 -07001095EXPORT_SYMBOL_GPL(do_tcp_sendpages);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001096
Tom Herbert306b13e2017-07-28 16:22:41 -07001097int tcp_sendpage_locked(struct sock *sk, struct page *page, int offset,
1098 size_t size, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001099{
Eric Dumazetdead7cd2018-02-19 11:56:49 -08001100 if (!(sk->sk_route_caps & NETIF_F_SG))
Eric Dumazetbd9dfc52017-08-25 06:27:05 -07001101 return sock_no_sendpage_locked(sk, page, offset, size, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001102
Soheil Hassas Yeganehd7722e82016-09-19 23:39:15 -04001103 tcp_rate_check_app_limited(sk); /* is sending application-limited? */
1104
Tom Herbert306b13e2017-07-28 16:22:41 -07001105 return do_tcp_sendpages(sk, page, offset, size, flags);
1106}
David S. Miller774c4672017-08-16 15:40:44 -07001107EXPORT_SYMBOL_GPL(tcp_sendpage_locked);
Tom Herbert306b13e2017-07-28 16:22:41 -07001108
1109int tcp_sendpage(struct sock *sk, struct page *page, int offset,
1110 size_t size, int flags)
1111{
1112 int ret;
1113
1114 lock_sock(sk);
1115 ret = tcp_sendpage_locked(sk, page, offset, size, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001116 release_sock(sk);
Tom Herbert306b13e2017-07-28 16:22:41 -07001117
1118 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001119}
Eric Dumazet4bc2f182010-07-09 21:22:10 +00001120EXPORT_SYMBOL(tcp_sendpage);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001121
Yuchung Chengcf60af02012-07-19 06:43:09 +00001122void tcp_free_fastopen_req(struct tcp_sock *tp)
1123{
Ian Morris00db4122015-04-03 09:17:27 +01001124 if (tp->fastopen_req) {
Yuchung Chengcf60af02012-07-19 06:43:09 +00001125 kfree(tp->fastopen_req);
1126 tp->fastopen_req = NULL;
1127 }
1128}
1129
Eric Dumazetf5ddcbb2014-02-20 10:09:18 -08001130static int tcp_sendmsg_fastopen(struct sock *sk, struct msghdr *msg,
Willem de Bruijnf859a442019-01-25 11:17:23 -05001131 int *copied, size_t size,
1132 struct ubuf_info *uarg)
Yuchung Chengcf60af02012-07-19 06:43:09 +00001133{
1134 struct tcp_sock *tp = tcp_sk(sk);
Wei Wang19f6d3f2017-01-23 10:59:22 -08001135 struct inet_sock *inet = inet_sk(sk);
Wei Wangba615f62017-05-24 09:59:31 -07001136 struct sockaddr *uaddr = msg->msg_name;
Yuchung Chengcf60af02012-07-19 06:43:09 +00001137 int err, flags;
1138
Haishuang Yane1cfcbe2017-09-27 11:35:40 +08001139 if (!(sock_net(sk)->ipv4.sysctl_tcp_fastopen & TFO_CLIENT_ENABLE) ||
Wei Wangba615f62017-05-24 09:59:31 -07001140 (uaddr && msg->msg_namelen >= sizeof(uaddr->sa_family) &&
1141 uaddr->sa_family == AF_UNSPEC))
Yuchung Chengcf60af02012-07-19 06:43:09 +00001142 return -EOPNOTSUPP;
Ian Morris00db4122015-04-03 09:17:27 +01001143 if (tp->fastopen_req)
Yuchung Chengcf60af02012-07-19 06:43:09 +00001144 return -EALREADY; /* Another Fast Open is in progress */
1145
1146 tp->fastopen_req = kzalloc(sizeof(struct tcp_fastopen_request),
1147 sk->sk_allocation);
Ian Morris51456b22015-04-03 09:17:26 +01001148 if (unlikely(!tp->fastopen_req))
Yuchung Chengcf60af02012-07-19 06:43:09 +00001149 return -ENOBUFS;
1150 tp->fastopen_req->data = msg;
Eric Dumazetf5ddcbb2014-02-20 10:09:18 -08001151 tp->fastopen_req->size = size;
Willem de Bruijnf859a442019-01-25 11:17:23 -05001152 tp->fastopen_req->uarg = uarg;
Yuchung Chengcf60af02012-07-19 06:43:09 +00001153
Wei Wang19f6d3f2017-01-23 10:59:22 -08001154 if (inet->defer_connect) {
1155 err = tcp_connect(sk);
1156 /* Same failure procedure as in tcp_v4/6_connect */
1157 if (err) {
1158 tcp_set_state(sk, TCP_CLOSE);
1159 inet->inet_dport = 0;
1160 sk->sk_route_caps = 0;
1161 }
1162 }
Yuchung Chengcf60af02012-07-19 06:43:09 +00001163 flags = (msg->msg_flags & MSG_DONTWAIT) ? O_NONBLOCK : 0;
Wei Wangba615f62017-05-24 09:59:31 -07001164 err = __inet_stream_connect(sk->sk_socket, uaddr,
Willy Tarreau3979ad72017-01-25 14:42:46 +01001165 msg->msg_namelen, flags, 1);
Wei Wang7db92362017-03-01 13:29:48 -08001166 /* fastopen_req could already be freed in __inet_stream_connect
1167 * if the connection times out or gets rst
1168 */
1169 if (tp->fastopen_req) {
1170 *copied = tp->fastopen_req->copied;
1171 tcp_free_fastopen_req(tp);
1172 inet->defer_connect = 0;
1173 }
Yuchung Chengcf60af02012-07-19 06:43:09 +00001174 return err;
1175}
1176
Tom Herbert306b13e2017-07-28 16:22:41 -07001177int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001178{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001179 struct tcp_sock *tp = tcp_sk(sk);
Willem de Bruijnf214f912017-08-03 16:29:44 -04001180 struct ubuf_info *uarg = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001181 struct sk_buff *skb;
Soheil Hassas Yeganehc14ac942016-04-02 23:08:12 -04001182 struct sockcm_cookie sockc;
Al Viro57be5bd2014-11-28 13:40:20 -05001183 int flags, err, copied = 0;
1184 int mss_now = 0, size_goal, copied_syn = 0;
Eric Dumazet1a9914882019-08-09 05:04:47 -07001185 int process_backlog = 0;
Eric Dumazet74d4a8f2018-02-19 11:56:48 -08001186 bool zc = false;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001187 long timeo;
1188
Linus Torvalds1da177e2005-04-16 15:20:36 -07001189 flags = msg->msg_flags;
Willem de Bruijnf214f912017-08-03 16:29:44 -04001190
Vincent Whitchurch5cf4a852018-09-06 15:54:59 +02001191 if (flags & MSG_ZEROCOPY && size && sock_flag(sk, SOCK_ZEROCOPY)) {
Eric Dumazet75c119a2017-10-05 22:21:27 -07001192 skb = tcp_write_queue_tail(sk);
Willem de Bruijnf214f912017-08-03 16:29:44 -04001193 uarg = sock_zerocopy_realloc(sk, size, skb_zcopy(skb));
1194 if (!uarg) {
1195 err = -ENOBUFS;
1196 goto out_err;
1197 }
1198
Eric Dumazetdead7cd2018-02-19 11:56:49 -08001199 zc = sk->sk_route_caps & NETIF_F_SG;
Willem de Bruijn02583ad2017-12-22 19:00:19 -05001200 if (!zc)
Willem de Bruijnf214f912017-08-03 16:29:44 -04001201 uarg->zerocopy = 0;
1202 }
1203
Yuchung Cheng16ae6aa2018-04-25 11:33:08 -07001204 if (unlikely(flags & MSG_FASTOPEN || inet_sk(sk)->defer_connect) &&
1205 !tp->repair) {
Willem de Bruijnf859a442019-01-25 11:17:23 -05001206 err = tcp_sendmsg_fastopen(sk, msg, &copied_syn, size, uarg);
Yuchung Chengcf60af02012-07-19 06:43:09 +00001207 if (err == -EINPROGRESS && copied_syn > 0)
1208 goto out;
1209 else if (err)
1210 goto out_err;
Yuchung Chengcf60af02012-07-19 06:43:09 +00001211 }
1212
Linus Torvalds1da177e2005-04-16 15:20:36 -07001213 timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
1214
Soheil Hassas Yeganehd7722e82016-09-19 23:39:15 -04001215 tcp_rate_check_app_limited(sk); /* is sending application-limited? */
1216
Jerry Chu83368862012-08-31 12:29:12 +00001217 /* Wait for a connection to finish. One exception is TCP Fast Open
1218 * (passive side) where data is allowed to be sent before a connection
1219 * is fully established.
1220 */
1221 if (((1 << sk->sk_state) & ~(TCPF_ESTABLISHED | TCPF_CLOSE_WAIT)) &&
1222 !tcp_passive_fastopen(sk)) {
Yuvaraja Mariappan686a5622015-10-06 10:53:29 -07001223 err = sk_stream_wait_connect(sk, &timeo);
1224 if (err != 0)
Yuchung Chengcf60af02012-07-19 06:43:09 +00001225 goto do_error;
Jerry Chu83368862012-08-31 12:29:12 +00001226 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001227
Pavel Emelyanovc0e88ff2012-04-19 03:41:01 +00001228 if (unlikely(tp->repair)) {
1229 if (tp->repair_queue == TCP_RECV_QUEUE) {
1230 copied = tcp_send_rcvq(sk, msg, size);
Christoph Paasch5924f172014-06-28 18:26:37 +02001231 goto out_nopush;
Pavel Emelyanovc0e88ff2012-04-19 03:41:01 +00001232 }
1233
1234 err = -EINVAL;
1235 if (tp->repair_queue == TCP_NO_QUEUE)
1236 goto out_err;
1237
1238 /* 'common' sending to sendq */
1239 }
1240
Willem de Bruijn657a0662018-07-06 10:12:56 -04001241 sockcm_init(&sockc, sk);
Soheil Hassas Yeganehc14ac942016-04-02 23:08:12 -04001242 if (msg->msg_controllen) {
1243 err = sock_cmsg_send(sk, msg, &sockc);
1244 if (unlikely(err)) {
1245 err = -EINVAL;
1246 goto out_err;
1247 }
1248 }
1249
Linus Torvalds1da177e2005-04-16 15:20:36 -07001250 /* This should be in poll */
Eric Dumazet9cd3e072015-11-29 20:03:10 -08001251 sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001252
Linus Torvalds1da177e2005-04-16 15:20:36 -07001253 /* Ok commence sending. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001254 copied = 0;
1255
Eric Dumazetd41a69f2016-04-29 14:16:53 -07001256restart:
1257 mss_now = tcp_send_mss(sk, &size_goal, flags);
1258
Linus Torvalds1da177e2005-04-16 15:20:36 -07001259 err = -EPIPE;
1260 if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
Eric Dumazet79d86652016-11-02 14:41:50 -07001261 goto do_error;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001262
Al Viro01e97e62014-12-15 21:39:31 -05001263 while (msg_data_left(msg)) {
Al Viro57be5bd2014-11-28 13:40:20 -05001264 int copy = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001265
Al Viro57be5bd2014-11-28 13:40:20 -05001266 skb = tcp_write_queue_tail(sk);
Eric Dumazet65ec6092018-02-19 11:56:50 -08001267 if (skb)
1268 copy = size_goal - skb->len;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001269
Martin KaFai Lauc134ecb2016-04-25 14:44:48 -07001270 if (copy <= 0 || !tcp_skb_can_collapse_to(skb)) {
Eric Dumazet3613b3d2016-09-15 09:33:02 -07001271 bool first_skb;
1272
Linus Torvalds1da177e2005-04-16 15:20:36 -07001273new_segment:
Al Viro57be5bd2014-11-28 13:40:20 -05001274 if (!sk_stream_memory_free(sk))
1275 goto wait_for_sndbuf;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001276
Eric Dumazet1a9914882019-08-09 05:04:47 -07001277 if (unlikely(process_backlog >= 16)) {
1278 process_backlog = 0;
1279 if (sk_flush_backlog(sk))
1280 goto restart;
Eric Dumazetd4011232016-05-02 21:49:25 -07001281 }
Eric Dumazet75c119a2017-10-05 22:21:27 -07001282 first_skb = tcp_rtx_and_write_queues_empty(sk);
Eric Dumazet472c2e02019-03-22 08:56:39 -07001283 skb = sk_stream_alloc_skb(sk, 0, sk->sk_allocation,
Eric Dumazet3613b3d2016-09-15 09:33:02 -07001284 first_skb);
Al Viro57be5bd2014-11-28 13:40:20 -05001285 if (!skb)
1286 goto wait_for_memory;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001287
Eric Dumazet1a9914882019-08-09 05:04:47 -07001288 process_backlog++;
Eric Dumazetdead7cd2018-02-19 11:56:49 -08001289 skb->ip_summed = CHECKSUM_PARTIAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001290
Al Viro57be5bd2014-11-28 13:40:20 -05001291 skb_entail(sk, skb);
1292 copy = size_goal;
Andrey Vagin9d186ca2014-08-13 16:03:10 +04001293
Al Viro57be5bd2014-11-28 13:40:20 -05001294 /* All packets are restored as if they have
Eric Dumazetd3edd062018-09-21 08:51:50 -07001295 * already been sent. skb_mstamp_ns isn't set to
Al Viro57be5bd2014-11-28 13:40:20 -05001296 * avoid wrong rtt estimation.
1297 */
1298 if (tp->repair)
1299 TCP_SKB_CB(skb)->sacked |= TCPCB_REPAIRED;
1300 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001301
Al Viro57be5bd2014-11-28 13:40:20 -05001302 /* Try to append data to the end of skb. */
Al Viro01e97e62014-12-15 21:39:31 -05001303 if (copy > msg_data_left(msg))
1304 copy = msg_data_left(msg);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001305
Al Viro57be5bd2014-11-28 13:40:20 -05001306 /* Where to copy to? */
Willem de Bruijn02583ad2017-12-22 19:00:19 -05001307 if (skb_availroom(skb) > 0 && !zc) {
Al Viro57be5bd2014-11-28 13:40:20 -05001308 /* We have some space in skb head. Superb! */
1309 copy = min_t(int, copy, skb_availroom(skb));
1310 err = skb_add_data_nocache(sk, skb, &msg->msg_iter, copy);
1311 if (err)
1312 goto do_fault;
Willem de Bruijn02583ad2017-12-22 19:00:19 -05001313 } else if (!zc) {
Al Viro57be5bd2014-11-28 13:40:20 -05001314 bool merge = true;
1315 int i = skb_shinfo(skb)->nr_frags;
1316 struct page_frag *pfrag = sk_page_frag(sk);
Eric Dumazet761965e2011-12-04 07:05:17 +00001317
Al Viro57be5bd2014-11-28 13:40:20 -05001318 if (!sk_page_frag_refill(sk, pfrag))
1319 goto wait_for_memory;
Eric Dumazet761965e2011-12-04 07:05:17 +00001320
Al Viro57be5bd2014-11-28 13:40:20 -05001321 if (!skb_can_coalesce(skb, i, pfrag->page,
1322 pfrag->offset)) {
Eric Dumazet74d4a8f2018-02-19 11:56:48 -08001323 if (i >= sysctl_max_skb_frags) {
Al Viro57be5bd2014-11-28 13:40:20 -05001324 tcp_mark_push(tp, skb);
1325 goto new_segment;
Eric Dumazet5640f762012-09-23 23:04:42 +00001326 }
Al Viro57be5bd2014-11-28 13:40:20 -05001327 merge = false;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001328 }
1329
Al Viro57be5bd2014-11-28 13:40:20 -05001330 copy = min_t(int, copy, pfrag->size - pfrag->offset);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001331
Al Viro57be5bd2014-11-28 13:40:20 -05001332 if (!sk_wmem_schedule(sk, copy))
1333 goto wait_for_memory;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001334
Al Viro57be5bd2014-11-28 13:40:20 -05001335 err = skb_copy_to_page_nocache(sk, &msg->msg_iter, skb,
1336 pfrag->page,
1337 pfrag->offset,
1338 copy);
1339 if (err)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001340 goto do_error;
1341
Al Viro57be5bd2014-11-28 13:40:20 -05001342 /* Update the skb. */
1343 if (merge) {
1344 skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy);
1345 } else {
1346 skb_fill_page_desc(skb, i, pfrag->page,
1347 pfrag->offset, copy);
Eric Dumazet4e33e342017-02-17 09:11:42 -08001348 page_ref_inc(pfrag->page);
Al Viro57be5bd2014-11-28 13:40:20 -05001349 }
1350 pfrag->offset += copy;
Willem de Bruijnf214f912017-08-03 16:29:44 -04001351 } else {
1352 err = skb_zerocopy_iter_stream(sk, skb, msg, copy, uarg);
Willem de Bruijn111856c2017-12-22 19:00:18 -05001353 if (err == -EMSGSIZE || err == -EEXIST) {
1354 tcp_mark_push(tp, skb);
Willem de Bruijnf214f912017-08-03 16:29:44 -04001355 goto new_segment;
Willem de Bruijn111856c2017-12-22 19:00:18 -05001356 }
Willem de Bruijnf214f912017-08-03 16:29:44 -04001357 if (err < 0)
1358 goto do_error;
1359 copy = err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001360 }
Al Viro57be5bd2014-11-28 13:40:20 -05001361
1362 if (!copied)
1363 TCP_SKB_CB(skb)->tcp_flags &= ~TCPHDR_PSH;
1364
1365 tp->write_seq += copy;
1366 TCP_SKB_CB(skb)->end_seq += copy;
1367 tcp_skb_pcount_set(skb, 0);
1368
1369 copied += copy;
Al Viro01e97e62014-12-15 21:39:31 -05001370 if (!msg_data_left(msg)) {
Martin KaFai Lauc134ecb2016-04-25 14:44:48 -07001371 if (unlikely(flags & MSG_EOR))
1372 TCP_SKB_CB(skb)->eor = 1;
Al Viro57be5bd2014-11-28 13:40:20 -05001373 goto out;
1374 }
1375
Eric Dumazet65ec6092018-02-19 11:56:50 -08001376 if (skb->len < size_goal || (flags & MSG_OOB) || unlikely(tp->repair))
Al Viro57be5bd2014-11-28 13:40:20 -05001377 continue;
1378
1379 if (forced_push(tp)) {
1380 tcp_mark_push(tp, skb);
1381 __tcp_push_pending_frames(sk, mss_now, TCP_NAGLE_PUSH);
1382 } else if (skb == tcp_send_head(sk))
1383 tcp_push_one(sk, mss_now);
1384 continue;
1385
1386wait_for_sndbuf:
1387 set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1388wait_for_memory:
1389 if (copied)
1390 tcp_push(sk, flags & ~MSG_MORE, mss_now,
1391 TCP_NAGLE_PUSH, size_goal);
1392
Yuvaraja Mariappan686a5622015-10-06 10:53:29 -07001393 err = sk_stream_wait_memory(sk, &timeo);
1394 if (err != 0)
Al Viro57be5bd2014-11-28 13:40:20 -05001395 goto do_error;
1396
1397 mss_now = tcp_send_mss(sk, &size_goal, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001398 }
1399
1400out:
Soheil Hassas Yeganehad02c4f2017-01-04 11:19:34 -05001401 if (copied) {
Eric Dumazet4e8cc222017-10-05 22:21:23 -07001402 tcp_tx_timestamp(sk, sockc.tsflags);
Eric Dumazetf54b3112013-12-05 22:36:05 -08001403 tcp_push(sk, flags, mss_now, tp->nonagle, size_goal);
Soheil Hassas Yeganehad02c4f2017-01-04 11:19:34 -05001404 }
Christoph Paasch5924f172014-06-28 18:26:37 +02001405out_nopush:
Willem de Bruijnf214f912017-08-03 16:29:44 -04001406 sock_zerocopy_put(uarg);
Yuchung Chengcf60af02012-07-19 06:43:09 +00001407 return copied + copied_syn;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001408
Linus Torvalds1da177e2005-04-16 15:20:36 -07001409do_error:
Eric Dumazetfdfc5c82019-08-26 09:19:15 -07001410 skb = tcp_write_queue_tail(sk);
1411do_fault:
1412 tcp_remove_empty_skb(sk, skb);
1413
Yuchung Chengcf60af02012-07-19 06:43:09 +00001414 if (copied + copied_syn)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001415 goto out;
1416out_err:
Willem de Bruijn52900d22018-11-30 15:32:40 -05001417 sock_zerocopy_put_abort(uarg, true);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001418 err = sk_stream_error(sk, flags, err);
Jason Baronce5ec442015-05-20 15:52:53 +00001419 /* make sure we wake any epoll edge trigger waiter */
Francis Yanb0f71bd2016-11-27 23:07:16 -08001420 if (unlikely(skb_queue_len(&sk->sk_write_queue) == 0 &&
1421 err == -EAGAIN)) {
Jason Baronce5ec442015-05-20 15:52:53 +00001422 sk->sk_write_space(sk);
Francis Yanb0f71bd2016-11-27 23:07:16 -08001423 tcp_chrono_stop(sk, TCP_CHRONO_SNDBUF_LIMITED);
1424 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001425 return err;
1426}
David S. Miller774c4672017-08-16 15:40:44 -07001427EXPORT_SYMBOL_GPL(tcp_sendmsg_locked);
Tom Herbert306b13e2017-07-28 16:22:41 -07001428
1429int tcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
1430{
1431 int ret;
1432
1433 lock_sock(sk);
1434 ret = tcp_sendmsg_locked(sk, msg, size);
1435 release_sock(sk);
1436
1437 return ret;
1438}
Eric Dumazet4bc2f182010-07-09 21:22:10 +00001439EXPORT_SYMBOL(tcp_sendmsg);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001440
1441/*
1442 * Handle reading urgent data. BSD has very simple semantics for
1443 * this, no blocking and very strange errors 8)
1444 */
1445
Rami Rosen377f0a02009-03-31 14:43:17 -07001446static int tcp_recv_urg(struct sock *sk, struct msghdr *msg, int len, int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001447{
1448 struct tcp_sock *tp = tcp_sk(sk);
1449
1450 /* No URG data to read. */
1451 if (sock_flag(sk, SOCK_URGINLINE) || !tp->urg_data ||
1452 tp->urg_data == TCP_URG_READ)
1453 return -EINVAL; /* Yes this is right ! */
1454
1455 if (sk->sk_state == TCP_CLOSE && !sock_flag(sk, SOCK_DONE))
1456 return -ENOTCONN;
1457
1458 if (tp->urg_data & TCP_URG_VALID) {
1459 int err = 0;
1460 char c = tp->urg_data;
1461
1462 if (!(flags & MSG_PEEK))
1463 tp->urg_data = TCP_URG_READ;
1464
1465 /* Read urgent data. */
1466 msg->msg_flags |= MSG_OOB;
1467
1468 if (len > 0) {
1469 if (!(flags & MSG_TRUNC))
Al Viro7eab8d92014-04-06 21:51:23 -04001470 err = memcpy_to_msg(msg, &c, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001471 len = 1;
1472 } else
1473 msg->msg_flags |= MSG_TRUNC;
1474
1475 return err ? -EFAULT : len;
1476 }
1477
1478 if (sk->sk_state == TCP_CLOSE || (sk->sk_shutdown & RCV_SHUTDOWN))
1479 return 0;
1480
1481 /* Fixed the recv(..., MSG_OOB) behaviour. BSD docs and
1482 * the available implementations agree in this case:
1483 * this call should never block, independent of the
1484 * blocking state of the socket.
1485 * Mike <pall@rz.uni-karlsruhe.de>
1486 */
1487 return -EAGAIN;
1488}
1489
Pavel Emelyanovc0e88ff2012-04-19 03:41:01 +00001490static int tcp_peek_sndq(struct sock *sk, struct msghdr *msg, int len)
1491{
1492 struct sk_buff *skb;
1493 int copied = 0, err = 0;
1494
1495 /* XXX -- need to support SO_PEEK_OFF */
1496
Eric Dumazet75c119a2017-10-05 22:21:27 -07001497 skb_rbtree_walk(skb, &sk->tcp_rtx_queue) {
1498 err = skb_copy_datagram_msg(skb, 0, msg, skb->len);
1499 if (err)
1500 return err;
1501 copied += skb->len;
1502 }
1503
Pavel Emelyanovc0e88ff2012-04-19 03:41:01 +00001504 skb_queue_walk(&sk->sk_write_queue, skb) {
David S. Miller51f3d022014-11-05 16:46:40 -05001505 err = skb_copy_datagram_msg(skb, 0, msg, skb->len);
Pavel Emelyanovc0e88ff2012-04-19 03:41:01 +00001506 if (err)
1507 break;
1508
1509 copied += skb->len;
1510 }
1511
1512 return err ?: copied;
1513}
1514
Linus Torvalds1da177e2005-04-16 15:20:36 -07001515/* Clean up the receive buffer for full frames taken by the user,
1516 * then send an ACK if necessary. COPIED is the number of bytes
1517 * tcp_recvmsg has given to the user so far, it speeds up the
1518 * calculation of whether or not we must ACK for the sake of
1519 * a window update.
1520 */
Dan Williams3f334072013-12-30 17:12:07 -08001521static void tcp_cleanup_rbuf(struct sock *sk, int copied)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001522{
1523 struct tcp_sock *tp = tcp_sk(sk);
Eric Dumazeta2a385d2012-05-16 23:15:34 +00001524 bool time_to_ack = false;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001525
Linus Torvalds1da177e2005-04-16 15:20:36 -07001526 struct sk_buff *skb = skb_peek(&sk->sk_receive_queue);
1527
Ilpo Järvinend792c102009-11-13 13:56:33 -08001528 WARN(skb && !before(tp->copied_seq, TCP_SKB_CB(skb)->end_seq),
Joe Perches2af6fd82010-10-30 11:08:53 +00001529 "cleanup rbuf bug: copied %X seq %X rcvnxt %X\n",
Ilpo Järvinend792c102009-11-13 13:56:33 -08001530 tp->copied_seq, TCP_SKB_CB(skb)->end_seq, tp->rcv_nxt);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001531
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07001532 if (inet_csk_ack_scheduled(sk)) {
1533 const struct inet_connection_sock *icsk = inet_csk(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001534 /* Delayed ACKs frequently hit locked sockets during bulk
1535 * receive. */
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07001536 if (icsk->icsk_ack.blocked ||
Linus Torvalds1da177e2005-04-16 15:20:36 -07001537 /* Once-per-two-segments ACK was not sent by tcp_input.c */
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07001538 tp->rcv_nxt - tp->rcv_wup > icsk->icsk_ack.rcv_mss ||
Linus Torvalds1da177e2005-04-16 15:20:36 -07001539 /*
1540 * If this read emptied read buffer, we send ACK, if
1541 * connection is not bidirectional, user drained
1542 * receive buffer and there was a small segment
1543 * in queue.
1544 */
Alexey Kuznetsov1ef96962006-09-19 12:52:50 -07001545 (copied > 0 &&
1546 ((icsk->icsk_ack.pending & ICSK_ACK_PUSHED2) ||
1547 ((icsk->icsk_ack.pending & ICSK_ACK_PUSHED) &&
Wei Wang31954cd2019-01-25 10:53:19 -08001548 !inet_csk_in_pingpong_mode(sk))) &&
Alexey Kuznetsov1ef96962006-09-19 12:52:50 -07001549 !atomic_read(&sk->sk_rmem_alloc)))
Eric Dumazeta2a385d2012-05-16 23:15:34 +00001550 time_to_ack = true;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001551 }
1552
1553 /* We send an ACK if we can now advertise a non-zero window
1554 * which has been raised "significantly".
1555 *
1556 * Even if window raised up to infinity, do not send window open ACK
1557 * in states, where we will not receive more. It is useless.
1558 */
1559 if (copied > 0 && !time_to_ack && !(sk->sk_shutdown & RCV_SHUTDOWN)) {
1560 __u32 rcv_window_now = tcp_receive_window(tp);
1561
1562 /* Optimize, __tcp_select_window() is not cheap. */
1563 if (2*rcv_window_now <= tp->window_clamp) {
1564 __u32 new_window = __tcp_select_window(sk);
1565
1566 /* Send ACK now, if this read freed lots of space
1567 * in our buffer. Certainly, new_window is new window.
1568 * We can advertise it now, if it is not less than current one.
1569 * "Lots" means "at least twice" here.
1570 */
1571 if (new_window && new_window >= 2 * rcv_window_now)
Eric Dumazeta2a385d2012-05-16 23:15:34 +00001572 time_to_ack = true;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001573 }
1574 }
1575 if (time_to_ack)
1576 tcp_send_ack(sk);
1577}
1578
Eric Dumazetf26845b2013-01-09 20:59:09 +00001579static struct sk_buff *tcp_recv_skb(struct sock *sk, u32 seq, u32 *off)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001580{
1581 struct sk_buff *skb;
1582 u32 offset;
1583
Eric Dumazetf26845b2013-01-09 20:59:09 +00001584 while ((skb = skb_peek(&sk->sk_receive_queue)) != NULL) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001585 offset = seq - TCP_SKB_CB(skb)->seq;
Eric Dumazet9d691532016-02-01 21:03:08 -08001586 if (unlikely(TCP_SKB_CB(skb)->tcp_flags & TCPHDR_SYN)) {
1587 pr_err_once("%s: found a SYN, please report !\n", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001588 offset--;
Eric Dumazet9d691532016-02-01 21:03:08 -08001589 }
Eric Dumazete11ecdd2014-09-15 04:19:51 -07001590 if (offset < skb->len || (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001591 *off = offset;
1592 return skb;
1593 }
Eric Dumazetf26845b2013-01-09 20:59:09 +00001594 /* This looks weird, but this can happen if TCP collapsing
1595 * splitted a fat GRO packet, while we released socket lock
1596 * in skb_splice_bits()
1597 */
Dan Williams7bced392013-12-30 12:37:29 -08001598 sk_eat_skb(sk, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001599 }
1600 return NULL;
1601}
1602
1603/*
1604 * This routine provides an alternative to tcp_recvmsg() for routines
1605 * that would like to handle copying from skbuffs directly in 'sendfile'
1606 * fashion.
1607 * Note:
1608 * - It is assumed that the socket was locked by the caller.
1609 * - The routine does not block.
1610 * - At present, there is no support for reading OOB data
1611 * or for 'peeking' the socket using this routine
1612 * (although both would be easy to implement).
1613 */
1614int tcp_read_sock(struct sock *sk, read_descriptor_t *desc,
1615 sk_read_actor_t recv_actor)
1616{
1617 struct sk_buff *skb;
1618 struct tcp_sock *tp = tcp_sk(sk);
1619 u32 seq = tp->copied_seq;
1620 u32 offset;
1621 int copied = 0;
1622
1623 if (sk->sk_state == TCP_LISTEN)
1624 return -ENOTCONN;
1625 while ((skb = tcp_recv_skb(sk, seq, &offset)) != NULL) {
1626 if (offset < skb->len) {
Octavian Purdila374e7b52008-07-03 03:31:21 -07001627 int used;
1628 size_t len;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001629
1630 len = skb->len - offset;
1631 /* Stop reading if we hit a patch of urgent data */
1632 if (tp->urg_data) {
1633 u32 urg_offset = tp->urg_seq - seq;
1634 if (urg_offset < len)
1635 len = urg_offset;
1636 if (!len)
1637 break;
1638 }
1639 used = recv_actor(desc, skb, offset, len);
Eric Dumazetff905b12013-01-10 07:06:10 +00001640 if (used <= 0) {
Jens Axboeddb61a52007-06-23 23:07:50 -07001641 if (!copied)
1642 copied = used;
1643 break;
1644 } else if (used <= len) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001645 seq += used;
1646 copied += used;
1647 offset += used;
1648 }
Willy Tarreau02275a22012-12-02 11:49:27 +00001649 /* If recv_actor drops the lock (e.g. TCP splice
Octavian Purdila293ad602008-06-04 15:45:58 -07001650 * receive) the skb pointer might be invalid when
1651 * getting here: tcp_collapse might have deleted it
1652 * while aggregating skbs from the socket queue.
1653 */
Willy Tarreau02275a22012-12-02 11:49:27 +00001654 skb = tcp_recv_skb(sk, seq - 1, &offset);
1655 if (!skb)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001656 break;
Willy Tarreau02275a22012-12-02 11:49:27 +00001657 /* TCP coalescing might have appended data to the skb.
1658 * Try to splice more frags
1659 */
1660 if (offset + 1 != skb->len)
1661 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001662 }
Eric Dumazete11ecdd2014-09-15 04:19:51 -07001663 if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) {
Dan Williams7bced392013-12-30 12:37:29 -08001664 sk_eat_skb(sk, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001665 ++seq;
1666 break;
1667 }
Dan Williams7bced392013-12-30 12:37:29 -08001668 sk_eat_skb(sk, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001669 if (!desc->count)
1670 break;
Steven J. Magnanibaff42a2010-03-30 13:56:01 -07001671 tp->copied_seq = seq;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001672 }
1673 tp->copied_seq = seq;
1674
1675 tcp_rcv_space_adjust(sk);
1676
1677 /* Clean up data we have read: This will do ACK frames. */
Eric Dumazetf26845b2013-01-09 20:59:09 +00001678 if (copied > 0) {
1679 tcp_recv_skb(sk, seq, &offset);
Chris Leech0e4b4992006-05-23 18:00:16 -07001680 tcp_cleanup_rbuf(sk, copied);
Eric Dumazetf26845b2013-01-09 20:59:09 +00001681 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001682 return copied;
1683}
Eric Dumazet4bc2f182010-07-09 21:22:10 +00001684EXPORT_SYMBOL(tcp_read_sock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001685
Tom Herbert32035582016-08-28 14:43:18 -07001686int tcp_peek_len(struct socket *sock)
1687{
1688 return tcp_inq(sock->sk);
1689}
1690EXPORT_SYMBOL(tcp_peek_len);
1691
Eric Dumazetd1361842018-04-16 10:33:35 -07001692/* Make sure sk_rcvbuf is big enough to satisfy SO_RCVLOWAT hint */
1693int tcp_set_rcvlowat(struct sock *sk, int val)
1694{
Soheil Hassas Yeganeh867f8162018-06-08 22:47:10 -04001695 int cap;
1696
1697 if (sk->sk_userlocks & SOCK_RCVBUF_LOCK)
1698 cap = sk->sk_rcvbuf >> 1;
1699 else
1700 cap = sock_net(sk)->ipv4.sysctl_tcp_rmem[2] >> 1;
1701 val = min(val, cap);
Eric Dumazeteac66402019-10-09 15:32:35 -07001702 WRITE_ONCE(sk->sk_rcvlowat, val ? : 1);
Eric Dumazet03f45c82018-04-16 10:33:37 -07001703
1704 /* Check if we need to signal EPOLLIN right now */
1705 tcp_data_ready(sk);
1706
Eric Dumazetd1361842018-04-16 10:33:35 -07001707 if (sk->sk_userlocks & SOCK_RCVBUF_LOCK)
1708 return 0;
1709
Eric Dumazetd1361842018-04-16 10:33:35 -07001710 val <<= 1;
Eric Dumazetd1361842018-04-16 10:33:35 -07001711 if (val > sk->sk_rcvbuf) {
1712 sk->sk_rcvbuf = val;
1713 tcp_sk(sk)->window_clamp = tcp_win_from_space(sk, val);
1714 }
1715 return 0;
1716}
1717EXPORT_SYMBOL(tcp_set_rcvlowat);
1718
Eric Dumazet05255b82018-04-27 08:58:08 -07001719#ifdef CONFIG_MMU
1720static const struct vm_operations_struct tcp_vm_ops = {
1721};
1722
Eric Dumazet93ab6cc2018-04-16 10:33:38 -07001723int tcp_mmap(struct file *file, struct socket *sock,
1724 struct vm_area_struct *vma)
1725{
Eric Dumazet05255b82018-04-27 08:58:08 -07001726 if (vma->vm_flags & (VM_WRITE | VM_EXEC))
1727 return -EPERM;
1728 vma->vm_flags &= ~(VM_MAYWRITE | VM_MAYEXEC);
1729
1730 /* Instruct vm_insert_page() to not down_read(mmap_sem) */
1731 vma->vm_flags |= VM_MIXEDMAP;
1732
1733 vma->vm_ops = &tcp_vm_ops;
1734 return 0;
1735}
1736EXPORT_SYMBOL(tcp_mmap);
1737
1738static int tcp_zerocopy_receive(struct sock *sk,
1739 struct tcp_zerocopy_receive *zc)
1740{
1741 unsigned long address = (unsigned long)zc->address;
1742 const skb_frag_t *frags = NULL;
1743 u32 length = 0, seq, offset;
1744 struct vm_area_struct *vma;
1745 struct sk_buff *skb = NULL;
Eric Dumazet93ab6cc2018-04-16 10:33:38 -07001746 struct tcp_sock *tp;
Soheil Hassas Yeganeh8f2b0292018-09-26 16:57:03 -04001747 int inq;
Eric Dumazet93ab6cc2018-04-16 10:33:38 -07001748 int ret;
1749
Eric Dumazet05255b82018-04-27 08:58:08 -07001750 if (address & (PAGE_SIZE - 1) || address != zc->address)
Eric Dumazet93ab6cc2018-04-16 10:33:38 -07001751 return -EINVAL;
1752
Eric Dumazet93ab6cc2018-04-16 10:33:38 -07001753 if (sk->sk_state == TCP_LISTEN)
Eric Dumazet05255b82018-04-27 08:58:08 -07001754 return -ENOTCONN;
Eric Dumazet93ab6cc2018-04-16 10:33:38 -07001755
1756 sock_rps_record_flow(sk);
1757
Eric Dumazet05255b82018-04-27 08:58:08 -07001758 down_read(&current->mm->mmap_sem);
1759
1760 ret = -EINVAL;
1761 vma = find_vma(current->mm, address);
1762 if (!vma || vma->vm_start > address || vma->vm_ops != &tcp_vm_ops)
Eric Dumazet93ab6cc2018-04-16 10:33:38 -07001763 goto out;
Eric Dumazet05255b82018-04-27 08:58:08 -07001764 zc->length = min_t(unsigned long, zc->length, vma->vm_end - address);
1765
Eric Dumazet93ab6cc2018-04-16 10:33:38 -07001766 tp = tcp_sk(sk);
1767 seq = tp->copied_seq;
Soheil Hassas Yeganeh8f2b0292018-09-26 16:57:03 -04001768 inq = tcp_inq(sk);
1769 zc->length = min_t(u32, zc->length, inq);
Eric Dumazet05255b82018-04-27 08:58:08 -07001770 zc->length &= ~(PAGE_SIZE - 1);
Soheil Hassas Yeganeh8f2b0292018-09-26 16:57:03 -04001771 if (zc->length) {
1772 zap_page_range(vma, address, zc->length);
1773 zc->recv_skip_hint = 0;
1774 } else {
1775 zc->recv_skip_hint = inq;
1776 }
Eric Dumazet05255b82018-04-27 08:58:08 -07001777 ret = 0;
1778 while (length + PAGE_SIZE <= zc->length) {
1779 if (zc->recv_skip_hint < PAGE_SIZE) {
1780 if (skb) {
1781 skb = skb->next;
1782 offset = seq - TCP_SKB_CB(skb)->seq;
1783 } else {
1784 skb = tcp_recv_skb(sk, seq, &offset);
1785 }
1786
1787 zc->recv_skip_hint = skb->len - offset;
1788 offset -= skb_headlen(skb);
1789 if ((int)offset < 0 || skb_has_frag_list(skb))
1790 break;
1791 frags = skb_shinfo(skb)->frags;
1792 while (offset) {
Matthew Wilcox (Oracle)d8e18a52019-07-22 20:08:26 -07001793 if (skb_frag_size(frags) > offset)
Eric Dumazet05255b82018-04-27 08:58:08 -07001794 goto out;
Matthew Wilcox (Oracle)d8e18a52019-07-22 20:08:26 -07001795 offset -= skb_frag_size(frags);
Eric Dumazet05255b82018-04-27 08:58:08 -07001796 frags++;
1797 }
1798 }
Jonathan Lemonb54c9d52019-07-30 07:40:33 -07001799 if (skb_frag_size(frags) != PAGE_SIZE || skb_frag_off(frags)) {
Soheil Hassas Yeganeh789762c2018-09-26 16:57:04 -04001800 int remaining = zc->recv_skip_hint;
1801
Eric Dumazet3afb0962019-10-02 20:19:59 -07001802 while (remaining && (skb_frag_size(frags) != PAGE_SIZE ||
Jonathan Lemonb54c9d52019-07-30 07:40:33 -07001803 skb_frag_off(frags))) {
Eric Dumazet3afb0962019-10-02 20:19:59 -07001804 remaining -= skb_frag_size(frags);
Soheil Hassas Yeganeh789762c2018-09-26 16:57:04 -04001805 frags++;
1806 }
1807 zc->recv_skip_hint -= remaining;
Eric Dumazet05255b82018-04-27 08:58:08 -07001808 break;
Soheil Hassas Yeganeh789762c2018-09-26 16:57:04 -04001809 }
Eric Dumazet05255b82018-04-27 08:58:08 -07001810 ret = vm_insert_page(vma, address + length,
1811 skb_frag_page(frags));
1812 if (ret)
1813 break;
1814 length += PAGE_SIZE;
1815 seq += PAGE_SIZE;
1816 zc->recv_skip_hint -= PAGE_SIZE;
Eric Dumazet93ab6cc2018-04-16 10:33:38 -07001817 frags++;
1818 }
Eric Dumazet93ab6cc2018-04-16 10:33:38 -07001819out:
Eric Dumazet05255b82018-04-27 08:58:08 -07001820 up_read(&current->mm->mmap_sem);
1821 if (length) {
1822 tp->copied_seq = seq;
1823 tcp_rcv_space_adjust(sk);
1824
1825 /* Clean up data we have read: This will do ACK frames. */
1826 tcp_recv_skb(sk, seq, &offset);
1827 tcp_cleanup_rbuf(sk, length);
1828 ret = 0;
1829 if (length == zc->length)
1830 zc->recv_skip_hint = 0;
1831 } else {
1832 if (!zc->recv_skip_hint && sock_flag(sk, SOCK_DONE))
1833 ret = -EIO;
1834 }
1835 zc->length = length;
Eric Dumazet93ab6cc2018-04-16 10:33:38 -07001836 return ret;
1837}
Eric Dumazet05255b82018-04-27 08:58:08 -07001838#endif
Eric Dumazet93ab6cc2018-04-16 10:33:38 -07001839
Mike Maloney98aaa912017-08-22 17:08:48 -04001840static void tcp_update_recv_tstamps(struct sk_buff *skb,
Deepa Dinamani97184752019-02-02 07:34:51 -08001841 struct scm_timestamping_internal *tss)
Mike Maloney98aaa912017-08-22 17:08:48 -04001842{
1843 if (skb->tstamp)
Deepa Dinamani97184752019-02-02 07:34:51 -08001844 tss->ts[0] = ktime_to_timespec64(skb->tstamp);
Mike Maloney98aaa912017-08-22 17:08:48 -04001845 else
Deepa Dinamani97184752019-02-02 07:34:51 -08001846 tss->ts[0] = (struct timespec64) {0};
Mike Maloney98aaa912017-08-22 17:08:48 -04001847
1848 if (skb_hwtstamps(skb)->hwtstamp)
Deepa Dinamani97184752019-02-02 07:34:51 -08001849 tss->ts[2] = ktime_to_timespec64(skb_hwtstamps(skb)->hwtstamp);
Mike Maloney98aaa912017-08-22 17:08:48 -04001850 else
Deepa Dinamani97184752019-02-02 07:34:51 -08001851 tss->ts[2] = (struct timespec64) {0};
Mike Maloney98aaa912017-08-22 17:08:48 -04001852}
1853
1854/* Similar to __sock_recv_timestamp, but does not require an skb */
Wei Yongjun809a79e2018-01-10 07:43:15 +00001855static void tcp_recv_timestamp(struct msghdr *msg, const struct sock *sk,
Deepa Dinamani97184752019-02-02 07:34:51 -08001856 struct scm_timestamping_internal *tss)
Mike Maloney98aaa912017-08-22 17:08:48 -04001857{
Deepa Dinamani887feae2019-02-02 07:34:50 -08001858 int new_tstamp = sock_flag(sk, SOCK_TSTAMP_NEW);
Mike Maloney98aaa912017-08-22 17:08:48 -04001859 bool has_timestamping = false;
1860
1861 if (tss->ts[0].tv_sec || tss->ts[0].tv_nsec) {
1862 if (sock_flag(sk, SOCK_RCVTSTAMP)) {
1863 if (sock_flag(sk, SOCK_RCVTSTAMPNS)) {
Deepa Dinamani887feae2019-02-02 07:34:50 -08001864 if (new_tstamp) {
1865 struct __kernel_timespec kts = {tss->ts[0].tv_sec, tss->ts[0].tv_nsec};
Mike Maloney98aaa912017-08-22 17:08:48 -04001866
Deepa Dinamani887feae2019-02-02 07:34:50 -08001867 put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMPNS_NEW,
1868 sizeof(kts), &kts);
1869 } else {
Deepa Dinamani97184752019-02-02 07:34:51 -08001870 struct timespec ts_old = timespec64_to_timespec(tss->ts[0]);
1871
Deepa Dinamani887feae2019-02-02 07:34:50 -08001872 put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMPNS_OLD,
Deepa Dinamani97184752019-02-02 07:34:51 -08001873 sizeof(ts_old), &ts_old);
Deepa Dinamani887feae2019-02-02 07:34:50 -08001874 }
1875 } else {
1876 if (new_tstamp) {
1877 struct __kernel_sock_timeval stv;
1878
1879 stv.tv_sec = tss->ts[0].tv_sec;
1880 stv.tv_usec = tss->ts[0].tv_nsec / 1000;
1881 put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMP_NEW,
1882 sizeof(stv), &stv);
1883 } else {
1884 struct __kernel_old_timeval tv;
1885
1886 tv.tv_sec = tss->ts[0].tv_sec;
1887 tv.tv_usec = tss->ts[0].tv_nsec / 1000;
1888 put_cmsg(msg, SOL_SOCKET, SO_TIMESTAMP_OLD,
1889 sizeof(tv), &tv);
1890 }
Mike Maloney98aaa912017-08-22 17:08:48 -04001891 }
1892 }
1893
1894 if (sk->sk_tsflags & SOF_TIMESTAMPING_SOFTWARE)
1895 has_timestamping = true;
1896 else
Deepa Dinamani97184752019-02-02 07:34:51 -08001897 tss->ts[0] = (struct timespec64) {0};
Mike Maloney98aaa912017-08-22 17:08:48 -04001898 }
1899
1900 if (tss->ts[2].tv_sec || tss->ts[2].tv_nsec) {
1901 if (sk->sk_tsflags & SOF_TIMESTAMPING_RAW_HARDWARE)
1902 has_timestamping = true;
1903 else
Deepa Dinamani97184752019-02-02 07:34:51 -08001904 tss->ts[2] = (struct timespec64) {0};
Mike Maloney98aaa912017-08-22 17:08:48 -04001905 }
1906
1907 if (has_timestamping) {
Deepa Dinamani97184752019-02-02 07:34:51 -08001908 tss->ts[1] = (struct timespec64) {0};
1909 if (sock_flag(sk, SOCK_TSTAMP_NEW))
1910 put_cmsg_scm_timestamping64(msg, tss);
1911 else
1912 put_cmsg_scm_timestamping(msg, tss);
Mike Maloney98aaa912017-08-22 17:08:48 -04001913 }
1914}
1915
Soheil Hassas Yeganehb75eba72018-05-01 15:39:15 -04001916static int tcp_inq_hint(struct sock *sk)
1917{
1918 const struct tcp_sock *tp = tcp_sk(sk);
1919 u32 copied_seq = READ_ONCE(tp->copied_seq);
1920 u32 rcv_nxt = READ_ONCE(tp->rcv_nxt);
1921 int inq;
1922
1923 inq = rcv_nxt - copied_seq;
1924 if (unlikely(inq < 0 || copied_seq != READ_ONCE(tp->copied_seq))) {
1925 lock_sock(sk);
1926 inq = tp->rcv_nxt - tp->copied_seq;
1927 release_sock(sk);
1928 }
Soheil Hassas Yeganeh6466e712019-03-06 13:01:36 -05001929 /* After receiving a FIN, tell the user-space to continue reading
1930 * by returning a non-zero inq.
1931 */
1932 if (inq == 0 && sock_flag(sk, SOCK_DONE))
1933 inq = 1;
Soheil Hassas Yeganehb75eba72018-05-01 15:39:15 -04001934 return inq;
1935}
1936
Linus Torvalds1da177e2005-04-16 15:20:36 -07001937/*
1938 * This routine copies from a sock struct into the user buffer.
1939 *
1940 * Technical note: in 2.3 we work on _locked_ socket, so that
1941 * tricks with *seq access order and skb->users are not required.
1942 * Probably, code can be easily improved even more.
1943 */
1944
Ying Xue1b784142015-03-02 15:37:48 +08001945int tcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int nonblock,
1946 int flags, int *addr_len)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001947{
1948 struct tcp_sock *tp = tcp_sk(sk);
1949 int copied = 0;
1950 u32 peek_seq;
1951 u32 *seq;
1952 unsigned long used;
Soheil Hassas Yeganehb75eba72018-05-01 15:39:15 -04001953 int err, inq;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001954 int target; /* Read at least this many bytes */
1955 long timeo;
Sabrina Dubrocadfbafc92015-07-24 18:19:25 +02001956 struct sk_buff *skb, *last;
Ilpo Järvinen77527312009-05-10 20:32:34 +00001957 u32 urg_hole = 0;
Deepa Dinamani97184752019-02-02 07:34:51 -08001958 struct scm_timestamping_internal tss;
Mike Maloney98aaa912017-08-22 17:08:48 -04001959 bool has_tss = false;
Soheil Hassas Yeganehb75eba72018-05-01 15:39:15 -04001960 bool has_cmsg;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001961
Willem de Bruijn4ed2d762014-08-04 22:11:49 -04001962 if (unlikely(flags & MSG_ERRQUEUE))
Willem de Bruijnf4713a32014-11-26 14:53:02 -05001963 return inet_recv_error(sk, msg, len, addr_len);
Willem de Bruijn4ed2d762014-08-04 22:11:49 -04001964
Eliezer Tamircbf55002013-07-08 16:20:34 +03001965 if (sk_can_busy_loop(sk) && skb_queue_empty(&sk->sk_receive_queue) &&
1966 (sk->sk_state == TCP_ESTABLISHED))
1967 sk_busy_loop(sk, nonblock);
Eliezer Tamird30e3832013-06-10 11:40:10 +03001968
Linus Torvalds1da177e2005-04-16 15:20:36 -07001969 lock_sock(sk);
1970
Linus Torvalds1da177e2005-04-16 15:20:36 -07001971 err = -ENOTCONN;
1972 if (sk->sk_state == TCP_LISTEN)
1973 goto out;
1974
Soheil Hassas Yeganehb75eba72018-05-01 15:39:15 -04001975 has_cmsg = tp->recvmsg_inq;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001976 timeo = sock_rcvtimeo(sk, nonblock);
1977
1978 /* Urgent data needs to be handled specially. */
1979 if (flags & MSG_OOB)
1980 goto recv_urg;
1981
Pavel Emelyanovc0e88ff2012-04-19 03:41:01 +00001982 if (unlikely(tp->repair)) {
1983 err = -EPERM;
1984 if (!(flags & MSG_PEEK))
1985 goto out;
1986
1987 if (tp->repair_queue == TCP_SEND_QUEUE)
1988 goto recv_sndq;
1989
1990 err = -EINVAL;
1991 if (tp->repair_queue == TCP_NO_QUEUE)
1992 goto out;
1993
1994 /* 'common' recv queue MSG_PEEK-ing */
1995 }
1996
Linus Torvalds1da177e2005-04-16 15:20:36 -07001997 seq = &tp->copied_seq;
1998 if (flags & MSG_PEEK) {
1999 peek_seq = tp->copied_seq;
2000 seq = &peek_seq;
2001 }
2002
2003 target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
2004
2005 do {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002006 u32 offset;
2007
2008 /* Are we at urgent data? Stop if we have read anything or have SIGURG pending. */
2009 if (tp->urg_data && tp->urg_seq == *seq) {
2010 if (copied)
2011 break;
2012 if (signal_pending(current)) {
2013 copied = timeo ? sock_intr_errno(timeo) : -EAGAIN;
2014 break;
2015 }
2016 }
2017
2018 /* Next get a buffer. */
2019
Sabrina Dubrocadfbafc92015-07-24 18:19:25 +02002020 last = skb_peek_tail(&sk->sk_receive_queue);
David S. Miller91521942009-05-28 21:35:47 -07002021 skb_queue_walk(&sk->sk_receive_queue, skb) {
Sabrina Dubrocadfbafc92015-07-24 18:19:25 +02002022 last = skb;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002023 /* Now that we have two receive queues this
2024 * shouldn't happen.
2025 */
Ilpo Järvinend792c102009-11-13 13:56:33 -08002026 if (WARN(before(*seq, TCP_SKB_CB(skb)->seq),
Randy Dunlape56b8ce2018-07-17 18:27:45 -07002027 "TCP recvmsg seq # bug: copied %X, seq %X, rcvnxt %X, fl %X\n",
Joe Perches2af6fd82010-10-30 11:08:53 +00002028 *seq, TCP_SKB_CB(skb)->seq, tp->rcv_nxt,
2029 flags))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002030 break;
Ilpo Järvinend792c102009-11-13 13:56:33 -08002031
Linus Torvalds1da177e2005-04-16 15:20:36 -07002032 offset = *seq - TCP_SKB_CB(skb)->seq;
Eric Dumazet9d691532016-02-01 21:03:08 -08002033 if (unlikely(TCP_SKB_CB(skb)->tcp_flags & TCPHDR_SYN)) {
2034 pr_err_once("%s: found a SYN, please report !\n", __func__);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002035 offset--;
Eric Dumazet9d691532016-02-01 21:03:08 -08002036 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002037 if (offset < skb->len)
2038 goto found_ok_skb;
Eric Dumazete11ecdd2014-09-15 04:19:51 -07002039 if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002040 goto found_fin_ok;
Joe Perches2af6fd82010-10-30 11:08:53 +00002041 WARN(!(flags & MSG_PEEK),
Randy Dunlape56b8ce2018-07-17 18:27:45 -07002042 "TCP recvmsg seq # bug 2: copied %X, seq %X, rcvnxt %X, fl %X\n",
Joe Perches2af6fd82010-10-30 11:08:53 +00002043 *seq, TCP_SKB_CB(skb)->seq, tp->rcv_nxt, flags);
David S. Miller91521942009-05-28 21:35:47 -07002044 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002045
2046 /* Well, if we have backlog, try to process it now yet. */
2047
2048 if (copied >= target && !sk->sk_backlog.tail)
2049 break;
2050
2051 if (copied) {
2052 if (sk->sk_err ||
2053 sk->sk_state == TCP_CLOSE ||
2054 (sk->sk_shutdown & RCV_SHUTDOWN) ||
2055 !timeo ||
David S. Miller518a09e2008-11-05 03:36:01 -08002056 signal_pending(current))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002057 break;
2058 } else {
2059 if (sock_flag(sk, SOCK_DONE))
2060 break;
2061
2062 if (sk->sk_err) {
2063 copied = sock_error(sk);
2064 break;
2065 }
2066
2067 if (sk->sk_shutdown & RCV_SHUTDOWN)
2068 break;
2069
2070 if (sk->sk_state == TCP_CLOSE) {
Eric Dumazetc47078d2018-07-07 23:15:56 -07002071 /* This occurs when user tries to read
2072 * from never connected socket.
2073 */
2074 copied = -ENOTCONN;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002075 break;
2076 }
2077
2078 if (!timeo) {
2079 copied = -EAGAIN;
2080 break;
2081 }
2082
2083 if (signal_pending(current)) {
2084 copied = sock_intr_errno(timeo);
2085 break;
2086 }
2087 }
2088
Chris Leech0e4b4992006-05-23 18:00:16 -07002089 tcp_cleanup_rbuf(sk, copied);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002090
Linus Torvalds1da177e2005-04-16 15:20:36 -07002091 if (copied >= target) {
2092 /* Do not sleep, just process backlog. */
2093 release_sock(sk);
2094 lock_sock(sk);
Sabrina Dubrocadfbafc92015-07-24 18:19:25 +02002095 } else {
2096 sk_wait_data(sk, &timeo, last);
2097 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002098
Ilpo Järvinen77527312009-05-10 20:32:34 +00002099 if ((flags & MSG_PEEK) &&
2100 (peek_seq - copied - urg_hole != tp->copied_seq)) {
Joe Perchese87cc472012-05-13 21:56:26 +00002101 net_dbg_ratelimited("TCP(%s:%d): Application bug, race in MSG_PEEK\n",
2102 current->comm,
2103 task_pid_nr(current));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002104 peek_seq = tp->copied_seq;
2105 }
2106 continue;
2107
Pedro Tammelafdb8b292018-12-06 10:45:28 -02002108found_ok_skb:
Linus Torvalds1da177e2005-04-16 15:20:36 -07002109 /* Ok so how much can we use? */
2110 used = skb->len - offset;
2111 if (len < used)
2112 used = len;
2113
2114 /* Do we have urgent data here? */
2115 if (tp->urg_data) {
2116 u32 urg_offset = tp->urg_seq - *seq;
2117 if (urg_offset < used) {
2118 if (!urg_offset) {
2119 if (!sock_flag(sk, SOCK_URGINLINE)) {
2120 ++*seq;
Ilpo Järvinen77527312009-05-10 20:32:34 +00002121 urg_hole++;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002122 offset++;
2123 used--;
2124 if (!used)
2125 goto skip_copy;
2126 }
2127 } else
2128 used = urg_offset;
2129 }
2130 }
2131
2132 if (!(flags & MSG_TRUNC)) {
David S. Miller51f3d022014-11-05 16:46:40 -05002133 err = skb_copy_datagram_msg(skb, offset, msg, used);
Dan Williams7bced392013-12-30 12:37:29 -08002134 if (err) {
2135 /* Exception. Bailout! */
2136 if (!copied)
2137 copied = -EFAULT;
2138 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002139 }
2140 }
2141
2142 *seq += used;
2143 copied += used;
2144 len -= used;
2145
2146 tcp_rcv_space_adjust(sk);
2147
2148skip_copy:
Florian Westphal31770e32017-08-30 19:24:58 +02002149 if (tp->urg_data && after(tp->copied_seq, tp->urg_seq)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002150 tp->urg_data = 0;
Florian Westphal31770e32017-08-30 19:24:58 +02002151 tcp_fast_path_check(sk);
2152 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002153 if (used + offset < skb->len)
2154 continue;
2155
Mike Maloney98aaa912017-08-22 17:08:48 -04002156 if (TCP_SKB_CB(skb)->has_rxtstamp) {
2157 tcp_update_recv_tstamps(skb, &tss);
2158 has_tss = true;
Soheil Hassas Yeganehb75eba72018-05-01 15:39:15 -04002159 has_cmsg = true;
Mike Maloney98aaa912017-08-22 17:08:48 -04002160 }
Eric Dumazete11ecdd2014-09-15 04:19:51 -07002161 if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002162 goto found_fin_ok;
Dan Williams7bced392013-12-30 12:37:29 -08002163 if (!(flags & MSG_PEEK))
2164 sk_eat_skb(sk, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002165 continue;
2166
Pedro Tammelafdb8b292018-12-06 10:45:28 -02002167found_fin_ok:
Linus Torvalds1da177e2005-04-16 15:20:36 -07002168 /* Process the FIN. */
2169 ++*seq;
Dan Williams7bced392013-12-30 12:37:29 -08002170 if (!(flags & MSG_PEEK))
2171 sk_eat_skb(sk, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002172 break;
2173 } while (len > 0);
2174
Linus Torvalds1da177e2005-04-16 15:20:36 -07002175 /* According to UNIX98, msg_name/msg_namelen are ignored
2176 * on connected socket. I was just happy when found this 8) --ANK
2177 */
2178
2179 /* Clean up data we have read: This will do ACK frames. */
Chris Leech0e4b4992006-05-23 18:00:16 -07002180 tcp_cleanup_rbuf(sk, copied);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002181
Linus Torvalds1da177e2005-04-16 15:20:36 -07002182 release_sock(sk);
Soheil Hassas Yeganehb75eba72018-05-01 15:39:15 -04002183
2184 if (has_cmsg) {
2185 if (has_tss)
2186 tcp_recv_timestamp(msg, sk, &tss);
2187 if (tp->recvmsg_inq) {
2188 inq = tcp_inq_hint(sk);
2189 put_cmsg(msg, SOL_TCP, TCP_CM_INQ, sizeof(inq), &inq);
2190 }
2191 }
2192
Linus Torvalds1da177e2005-04-16 15:20:36 -07002193 return copied;
2194
2195out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07002196 release_sock(sk);
2197 return err;
2198
2199recv_urg:
Rami Rosen377f0a02009-03-31 14:43:17 -07002200 err = tcp_recv_urg(sk, msg, len, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002201 goto out;
Pavel Emelyanovc0e88ff2012-04-19 03:41:01 +00002202
2203recv_sndq:
2204 err = tcp_peek_sndq(sk, msg, len);
2205 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002206}
Eric Dumazet4bc2f182010-07-09 21:22:10 +00002207EXPORT_SYMBOL(tcp_recvmsg);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002208
Ilpo Järvinen490d5042008-01-12 03:17:20 -08002209void tcp_set_state(struct sock *sk, int state)
2210{
2211 int oldstate = sk->sk_state;
2212
Lawrence Brakmod4487492018-01-25 16:14:15 -08002213 /* We defined a new enum for TCP states that are exported in BPF
2214 * so as not force the internal TCP states to be frozen. The
2215 * following checks will detect if an internal state value ever
2216 * differs from the BPF value. If this ever happens, then we will
2217 * need to remap the internal value to the BPF value before calling
2218 * tcp_call_bpf_2arg.
2219 */
2220 BUILD_BUG_ON((int)BPF_TCP_ESTABLISHED != (int)TCP_ESTABLISHED);
2221 BUILD_BUG_ON((int)BPF_TCP_SYN_SENT != (int)TCP_SYN_SENT);
2222 BUILD_BUG_ON((int)BPF_TCP_SYN_RECV != (int)TCP_SYN_RECV);
2223 BUILD_BUG_ON((int)BPF_TCP_FIN_WAIT1 != (int)TCP_FIN_WAIT1);
2224 BUILD_BUG_ON((int)BPF_TCP_FIN_WAIT2 != (int)TCP_FIN_WAIT2);
2225 BUILD_BUG_ON((int)BPF_TCP_TIME_WAIT != (int)TCP_TIME_WAIT);
2226 BUILD_BUG_ON((int)BPF_TCP_CLOSE != (int)TCP_CLOSE);
2227 BUILD_BUG_ON((int)BPF_TCP_CLOSE_WAIT != (int)TCP_CLOSE_WAIT);
2228 BUILD_BUG_ON((int)BPF_TCP_LAST_ACK != (int)TCP_LAST_ACK);
2229 BUILD_BUG_ON((int)BPF_TCP_LISTEN != (int)TCP_LISTEN);
2230 BUILD_BUG_ON((int)BPF_TCP_CLOSING != (int)TCP_CLOSING);
2231 BUILD_BUG_ON((int)BPF_TCP_NEW_SYN_RECV != (int)TCP_NEW_SYN_RECV);
2232 BUILD_BUG_ON((int)BPF_TCP_MAX_STATES != (int)TCP_MAX_STATES);
2233
2234 if (BPF_SOCK_OPS_TEST_FLAG(tcp_sk(sk), BPF_SOCK_OPS_STATE_CB_FLAG))
2235 tcp_call_bpf_2arg(sk, BPF_SOCK_OPS_STATE_CB, oldstate, state);
Song Liue8fce232017-10-23 09:20:27 -07002236
Ilpo Järvinen490d5042008-01-12 03:17:20 -08002237 switch (state) {
2238 case TCP_ESTABLISHED:
2239 if (oldstate != TCP_ESTABLISHED)
Pavel Emelyanov81cc8a72008-07-16 20:22:04 -07002240 TCP_INC_STATS(sock_net(sk), TCP_MIB_CURRESTAB);
Ilpo Järvinen490d5042008-01-12 03:17:20 -08002241 break;
2242
2243 case TCP_CLOSE:
2244 if (oldstate == TCP_CLOSE_WAIT || oldstate == TCP_ESTABLISHED)
Pavel Emelyanov81cc8a72008-07-16 20:22:04 -07002245 TCP_INC_STATS(sock_net(sk), TCP_MIB_ESTABRESETS);
Ilpo Järvinen490d5042008-01-12 03:17:20 -08002246
2247 sk->sk_prot->unhash(sk);
2248 if (inet_csk(sk)->icsk_bind_hash &&
2249 !(sk->sk_userlocks & SOCK_BINDPORT_LOCK))
Arnaldo Carvalho de Meloab1e0a12008-02-03 04:06:04 -08002250 inet_put_port(sk);
Ilpo Järvinen490d5042008-01-12 03:17:20 -08002251 /* fall through */
2252 default:
Jianjun Kong5a5f3a82008-11-03 00:24:34 -08002253 if (oldstate == TCP_ESTABLISHED)
Pavel Emelyanov74688e42008-07-16 20:22:46 -07002254 TCP_DEC_STATS(sock_net(sk), TCP_MIB_CURRESTAB);
Ilpo Järvinen490d5042008-01-12 03:17:20 -08002255 }
2256
2257 /* Change state AFTER socket is unhashed to avoid closed
2258 * socket sitting in hash tables.
2259 */
Yafang Shao563e0bb2017-12-20 11:12:51 +08002260 inet_sk_state_store(sk, state);
Ilpo Järvinen490d5042008-01-12 03:17:20 -08002261}
2262EXPORT_SYMBOL_GPL(tcp_set_state);
2263
Linus Torvalds1da177e2005-04-16 15:20:36 -07002264/*
2265 * State processing on a close. This implements the state shift for
2266 * sending our FIN frame. Note that we only send a FIN for some
2267 * states. A shutdown() may have already sent the FIN, or we may be
2268 * closed.
2269 */
2270
Arjan van de Ven9b5b5cf2005-11-29 16:21:38 -08002271static const unsigned char new_state[16] = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002272 /* current state: new state: action: */
Eric Dumazet0980c1e2015-03-24 15:58:53 -07002273 [0 /* (Invalid) */] = TCP_CLOSE,
2274 [TCP_ESTABLISHED] = TCP_FIN_WAIT1 | TCP_ACTION_FIN,
2275 [TCP_SYN_SENT] = TCP_CLOSE,
2276 [TCP_SYN_RECV] = TCP_FIN_WAIT1 | TCP_ACTION_FIN,
2277 [TCP_FIN_WAIT1] = TCP_FIN_WAIT1,
2278 [TCP_FIN_WAIT2] = TCP_FIN_WAIT2,
2279 [TCP_TIME_WAIT] = TCP_CLOSE,
2280 [TCP_CLOSE] = TCP_CLOSE,
2281 [TCP_CLOSE_WAIT] = TCP_LAST_ACK | TCP_ACTION_FIN,
2282 [TCP_LAST_ACK] = TCP_LAST_ACK,
2283 [TCP_LISTEN] = TCP_CLOSE,
2284 [TCP_CLOSING] = TCP_CLOSING,
2285 [TCP_NEW_SYN_RECV] = TCP_CLOSE, /* should not happen ! */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002286};
2287
2288static int tcp_close_state(struct sock *sk)
2289{
2290 int next = (int)new_state[sk->sk_state];
2291 int ns = next & TCP_STATE_MASK;
2292
2293 tcp_set_state(sk, ns);
2294
2295 return next & TCP_ACTION_FIN;
2296}
2297
2298/*
2299 * Shutdown the sending side of a connection. Much like close except
Satoru SATOH1f29b052008-04-21 02:27:58 -07002300 * that we don't receive shut down or sock_set_flag(sk, SOCK_DEAD).
Linus Torvalds1da177e2005-04-16 15:20:36 -07002301 */
2302
2303void tcp_shutdown(struct sock *sk, int how)
2304{
2305 /* We need to grab some memory, and put together a FIN,
2306 * and then put it into the queue to be sent.
2307 * Tim MacKenzie(tym@dibbler.cs.monash.edu.au) 4 Dec '92.
2308 */
2309 if (!(how & SEND_SHUTDOWN))
2310 return;
2311
2312 /* If we've already sent a FIN, or it's a closed state, skip this. */
2313 if ((1 << sk->sk_state) &
2314 (TCPF_ESTABLISHED | TCPF_SYN_SENT |
2315 TCPF_SYN_RECV | TCPF_CLOSE_WAIT)) {
2316 /* Clear out any half completed packets. FIN if needed. */
2317 if (tcp_close_state(sk))
2318 tcp_send_fin(sk);
2319 }
2320}
Eric Dumazet4bc2f182010-07-09 21:22:10 +00002321EXPORT_SYMBOL(tcp_shutdown);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002322
Arun Sharmaefcdbf22012-01-30 14:16:06 -08002323bool tcp_check_oom(struct sock *sk, int shift)
2324{
2325 bool too_many_orphans, out_of_socket_memory;
2326
2327 too_many_orphans = tcp_too_many_orphans(sk, shift);
2328 out_of_socket_memory = tcp_out_of_memory(sk);
2329
Joe Perchese87cc472012-05-13 21:56:26 +00002330 if (too_many_orphans)
2331 net_info_ratelimited("too many orphaned sockets\n");
2332 if (out_of_socket_memory)
2333 net_info_ratelimited("out of memory -- consider tuning tcp_mem\n");
Arun Sharmaefcdbf22012-01-30 14:16:06 -08002334 return too_many_orphans || out_of_socket_memory;
2335}
2336
Linus Torvalds1da177e2005-04-16 15:20:36 -07002337void tcp_close(struct sock *sk, long timeout)
2338{
2339 struct sk_buff *skb;
2340 int data_was_unread = 0;
Herbert Xu75c2d9072006-05-03 23:31:35 -07002341 int state;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002342
2343 lock_sock(sk);
2344 sk->sk_shutdown = SHUTDOWN_MASK;
2345
2346 if (sk->sk_state == TCP_LISTEN) {
2347 tcp_set_state(sk, TCP_CLOSE);
2348
2349 /* Special case. */
Arnaldo Carvalho de Melo0a5578c2005-08-09 20:11:41 -07002350 inet_csk_listen_stop(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002351
2352 goto adjudge_to_death;
2353 }
2354
2355 /* We need to flush the recv. buffs. We do this only on the
2356 * descriptor close, not protocol-sourced closes, because the
2357 * reader process may not have drained the data yet!
2358 */
2359 while ((skb = __skb_dequeue(&sk->sk_receive_queue)) != NULL) {
Eric Dumazete11ecdd2014-09-15 04:19:51 -07002360 u32 len = TCP_SKB_CB(skb)->end_seq - TCP_SKB_CB(skb)->seq;
2361
2362 if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)
2363 len--;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002364 data_was_unread += len;
2365 __kfree_skb(skb);
2366 }
2367
Hideo Aoki3ab224b2007-12-31 00:11:19 -08002368 sk_mem_reclaim(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002369
Konstantin Khorenko565b7b22010-06-24 21:54:58 -07002370 /* If socket has been already reset (e.g. in tcp_reset()) - kill it. */
2371 if (sk->sk_state == TCP_CLOSE)
2372 goto adjudge_to_death;
2373
Gerrit Renker65bb7232007-04-28 21:21:46 -07002374 /* As outlined in RFC 2525, section 2.17, we send a RST here because
2375 * data was lost. To witness the awful effects of the old behavior of
2376 * always doing a FIN, run an older 2.1.x kernel or 2.0.x, start a bulk
2377 * GET in an FTP client, suspend the process, wait for the client to
2378 * advertise a zero window, then kill -9 the FTP client, wheee...
2379 * Note: timeout is always zero in such a case.
Linus Torvalds1da177e2005-04-16 15:20:36 -07002380 */
Pavel Emelyanovee995282012-04-19 03:40:39 +00002381 if (unlikely(tcp_sk(sk)->repair)) {
2382 sk->sk_prot->disconnect(sk, 0);
2383 } else if (data_was_unread) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002384 /* Unread data was tossed, zap the connection. */
Eric Dumazet6aef70a2016-04-27 16:44:27 -07002385 NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONCLOSE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002386 tcp_set_state(sk, TCP_CLOSE);
Wu Fengguangaa133072009-09-02 23:45:45 -07002387 tcp_send_active_reset(sk, sk->sk_allocation);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002388 } else if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) {
2389 /* Check zero linger _after_ checking for unread data. */
2390 sk->sk_prot->disconnect(sk, 0);
Eric Dumazet6aef70a2016-04-27 16:44:27 -07002391 NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPABORTONDATA);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002392 } else if (tcp_close_state(sk)) {
2393 /* We FIN if the application ate all the data before
2394 * zapping the connection.
2395 */
2396
2397 /* RED-PEN. Formally speaking, we have broken TCP state
2398 * machine. State transitions:
2399 *
2400 * TCP_ESTABLISHED -> TCP_FIN_WAIT1
2401 * TCP_SYN_RECV -> TCP_FIN_WAIT1 (forget it, it's impossible)
2402 * TCP_CLOSE_WAIT -> TCP_LAST_ACK
2403 *
2404 * are legal only when FIN has been sent (i.e. in window),
2405 * rather than queued out of window. Purists blame.
2406 *
2407 * F.e. "RFC state" is ESTABLISHED,
2408 * if Linux state is FIN-WAIT-1, but FIN is still not sent.
2409 *
2410 * The visible declinations are that sometimes
2411 * we enter time-wait state, when it is not required really
2412 * (harmless), do not send active resets, when they are
2413 * required by specs (TCP_ESTABLISHED, TCP_CLOSE_WAIT, when
2414 * they look as CLOSING or LAST_ACK for Linux)
2415 * Probably, I missed some more holelets.
2416 * --ANK
Jerry Chu83368862012-08-31 12:29:12 +00002417 * XXX (TFO) - To start off we don't support SYN+ACK+FIN
2418 * in a single packet! (May consider it later but will
2419 * probably need API support or TCP_CORK SYN-ACK until
2420 * data is written and socket is closed.)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002421 */
2422 tcp_send_fin(sk);
2423 }
2424
2425 sk_stream_wait_close(sk, timeout);
2426
2427adjudge_to_death:
Herbert Xu75c2d9072006-05-03 23:31:35 -07002428 state = sk->sk_state;
2429 sock_hold(sk);
2430 sock_orphan(sk);
Herbert Xu75c2d9072006-05-03 23:31:35 -07002431
Linus Torvalds1da177e2005-04-16 15:20:36 -07002432 local_bh_disable();
2433 bh_lock_sock(sk);
Eric Dumazet8873c062018-10-01 23:24:26 -07002434 /* remove backlog if any, without releasing ownership. */
2435 __release_sock(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002436
Herbert Xueb4dea52008-12-29 23:04:08 -08002437 percpu_counter_inc(sk->sk_prot->orphan_count);
2438
Herbert Xu75c2d9072006-05-03 23:31:35 -07002439 /* Have we already been destroyed by a softirq or backlog? */
2440 if (state != TCP_CLOSE && sk->sk_state == TCP_CLOSE)
2441 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002442
2443 /* This is a (useful) BSD violating of the RFC. There is a
2444 * problem with TCP as specified in that the other end could
2445 * keep a socket open forever with no application left this end.
Jesper Juhlb10bd542014-02-09 23:30:32 +01002446 * We use a 1 minute timeout (about the same as BSD) then kill
Linus Torvalds1da177e2005-04-16 15:20:36 -07002447 * our end. If they send after that then tough - BUT: long enough
2448 * that we won't make the old 4*rto = almost no time - whoops
2449 * reset mistake.
2450 *
2451 * Nope, it was not mistake. It is really desired behaviour
2452 * f.e. on http servers, when such sockets are useless, but
2453 * consume significant resources. Let's do it with special
2454 * linger2 option. --ANK
2455 */
2456
2457 if (sk->sk_state == TCP_FIN_WAIT2) {
2458 struct tcp_sock *tp = tcp_sk(sk);
2459 if (tp->linger2 < 0) {
2460 tcp_set_state(sk, TCP_CLOSE);
2461 tcp_send_active_reset(sk, GFP_ATOMIC);
Eric Dumazet02a1d6e2016-04-27 16:44:39 -07002462 __NET_INC_STATS(sock_net(sk),
Pavel Emelyanovde0744a2008-07-16 20:31:16 -07002463 LINUX_MIB_TCPABORTONLINGER);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002464 } else {
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07002465 const int tmo = tcp_fin_time(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002466
2467 if (tmo > TCP_TIMEWAIT_LEN) {
David S. Miller52499af2006-07-31 22:32:09 -07002468 inet_csk_reset_keepalive_timer(sk,
2469 tmo - TCP_TIMEWAIT_LEN);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002470 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002471 tcp_time_wait(sk, TCP_FIN_WAIT2, tmo);
2472 goto out;
2473 }
2474 }
2475 }
2476 if (sk->sk_state != TCP_CLOSE) {
Hideo Aoki3ab224b2007-12-31 00:11:19 -08002477 sk_mem_reclaim(sk);
Arun Sharmaefcdbf22012-01-30 14:16:06 -08002478 if (tcp_check_oom(sk, 0)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002479 tcp_set_state(sk, TCP_CLOSE);
2480 tcp_send_active_reset(sk, GFP_ATOMIC);
Eric Dumazet02a1d6e2016-04-27 16:44:39 -07002481 __NET_INC_STATS(sock_net(sk),
Pavel Emelyanovde0744a2008-07-16 20:31:16 -07002482 LINUX_MIB_TCPABORTONMEMORY);
Dan Streetman4ee806d2018-01-18 16:14:26 -05002483 } else if (!check_net(sock_net(sk))) {
2484 /* Not possible to send reset; just close */
2485 tcp_set_state(sk, TCP_CLOSE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002486 }
2487 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002488
Jerry Chu83368862012-08-31 12:29:12 +00002489 if (sk->sk_state == TCP_CLOSE) {
2490 struct request_sock *req = tcp_sk(sk)->fastopen_rsk;
2491 /* We could get here with a non-NULL req if the socket is
2492 * aborted (e.g., closed with unread data) before 3WHS
2493 * finishes.
2494 */
Ian Morris00db4122015-04-03 09:17:27 +01002495 if (req)
Jerry Chu83368862012-08-31 12:29:12 +00002496 reqsk_fastopen_remove(sk, req, false);
Arnaldo Carvalho de Melo0a5578c2005-08-09 20:11:41 -07002497 inet_csk_destroy_sock(sk);
Jerry Chu83368862012-08-31 12:29:12 +00002498 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002499 /* Otherwise, socket is reprieved until protocol close. */
2500
2501out:
2502 bh_unlock_sock(sk);
2503 local_bh_enable();
Eric Dumazet8873c062018-10-01 23:24:26 -07002504 release_sock(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002505 sock_put(sk);
2506}
Eric Dumazet4bc2f182010-07-09 21:22:10 +00002507EXPORT_SYMBOL(tcp_close);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002508
2509/* These states need RST on ABORT according to RFC793 */
2510
Eric Dumazeta2a385d2012-05-16 23:15:34 +00002511static inline bool tcp_need_reset(int state)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002512{
2513 return (1 << state) &
2514 (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT | TCPF_FIN_WAIT1 |
2515 TCPF_FIN_WAIT2 | TCPF_SYN_RECV);
2516}
2517
Eric Dumazet75c119a2017-10-05 22:21:27 -07002518static void tcp_rtx_queue_purge(struct sock *sk)
2519{
2520 struct rb_node *p = rb_first(&sk->tcp_rtx_queue);
2521
2522 while (p) {
2523 struct sk_buff *skb = rb_to_skb(p);
2524
2525 p = rb_next(p);
2526 /* Since we are deleting whole queue, no need to
2527 * list_del(&skb->tcp_tsorted_anchor)
2528 */
2529 tcp_rtx_queue_unlink(skb, sk);
2530 sk_wmem_free_skb(sk, skb);
2531 }
2532}
2533
Eric Dumazetac3f09b2017-10-05 22:21:22 -07002534void tcp_write_queue_purge(struct sock *sk)
2535{
2536 struct sk_buff *skb;
2537
2538 tcp_chrono_stop(sk, TCP_CHRONO_BUSY);
2539 while ((skb = __skb_dequeue(&sk->sk_write_queue)) != NULL) {
2540 tcp_skb_tsorted_anchor_cleanup(skb);
2541 sk_wmem_free_skb(sk, skb);
2542 }
Eric Dumazet75c119a2017-10-05 22:21:27 -07002543 tcp_rtx_queue_purge(sk);
Eric Dumazet472c2e02019-03-22 08:56:39 -07002544 skb = sk->sk_tx_skb_cache;
2545 if (skb) {
Eric Dumazet472c2e02019-03-22 08:56:39 -07002546 __kfree_skb(skb);
2547 sk->sk_tx_skb_cache = NULL;
2548 }
Eric Dumazetac3f09b2017-10-05 22:21:22 -07002549 INIT_LIST_HEAD(&tcp_sk(sk)->tsorted_sent_queue);
2550 sk_mem_reclaim(sk);
2551 tcp_clear_all_retrans_hints(tcp_sk(sk));
Soheil Hassas Yeganehbffd1682018-04-14 20:44:46 -04002552 tcp_sk(sk)->packets_out = 0;
Eric Dumazet04c03112019-02-15 13:36:20 -08002553 inet_csk(sk)->icsk_backoff = 0;
Eric Dumazetac3f09b2017-10-05 22:21:22 -07002554}
2555
Linus Torvalds1da177e2005-04-16 15:20:36 -07002556int tcp_disconnect(struct sock *sk, int flags)
2557{
2558 struct inet_sock *inet = inet_sk(sk);
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07002559 struct inet_connection_sock *icsk = inet_csk(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002560 struct tcp_sock *tp = tcp_sk(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002561 int old_state = sk->sk_state;
2562
2563 if (old_state != TCP_CLOSE)
2564 tcp_set_state(sk, TCP_CLOSE);
2565
2566 /* ABORT function of RFC793 */
2567 if (old_state == TCP_LISTEN) {
Arnaldo Carvalho de Melo0a5578c2005-08-09 20:11:41 -07002568 inet_csk_listen_stop(sk);
Pavel Emelyanovee995282012-04-19 03:40:39 +00002569 } else if (unlikely(tp->repair)) {
2570 sk->sk_err = ECONNABORTED;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002571 } else if (tcp_need_reset(old_state) ||
2572 (tp->snd_nxt != tp->write_seq &&
2573 (1 << old_state) & (TCPF_CLOSING | TCPF_LAST_ACK))) {
Stephen Hemmingercaa20d9a2005-11-10 17:13:47 -08002574 /* The last check adjusts for discrepancy of Linux wrt. RFC
Linus Torvalds1da177e2005-04-16 15:20:36 -07002575 * states
2576 */
2577 tcp_send_active_reset(sk, gfp_any());
2578 sk->sk_err = ECONNRESET;
2579 } else if (old_state == TCP_SYN_SENT)
2580 sk->sk_err = ECONNRESET;
2581
2582 tcp_clear_xmit_timers(sk);
2583 __skb_queue_purge(&sk->sk_receive_queue);
Eric Dumazet8b27dae2019-03-22 08:56:40 -07002584 if (sk->sk_rx_skb_cache) {
2585 __kfree_skb(sk->sk_rx_skb_cache);
2586 sk->sk_rx_skb_cache = NULL;
2587 }
Eric Dumazet6508b672018-07-07 23:00:01 -07002588 tp->copied_seq = tp->rcv_nxt;
2589 tp->urg_data = 0;
David S. Millerfe067e82007-03-07 12:12:44 -08002590 tcp_write_queue_purge(sk);
Wei Wangcf1ef3f2017-04-20 14:45:46 -07002591 tcp_fastopen_active_disable_ofo_check(sk);
Yaogong Wang9f5afea2016-09-07 14:49:28 -07002592 skb_rbtree_purge(&tp->out_of_order_queue);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002593
Eric Dumazetc720c7e82009-10-15 06:30:45 +00002594 inet->inet_dport = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002595
2596 if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK))
2597 inet_reset_saddr(sk);
2598
2599 sk->sk_shutdown = 0;
2600 sock_reset_flag(sk, SOCK_DONE);
Eric Dumazet740b0f12014-02-26 14:02:48 -08002601 tp->srtt_us = 0;
Eric Dumazetb9e2e682019-01-17 11:23:36 -08002602 tp->mdev_us = jiffies_to_usecs(TCP_TIMEOUT_INIT);
Wei Wang3f6c65d2018-06-19 21:42:50 -07002603 tp->rcv_rtt_last_tsecr = 0;
Yuvaraja Mariappan686a5622015-10-06 10:53:29 -07002604 tp->write_seq += tp->max_window + 2;
2605 if (tp->write_seq == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002606 tp->write_seq = 1;
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07002607 icsk->icsk_backoff = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002608 tp->snd_cwnd = 2;
Arnaldo Carvalho de Melo6687e982005-08-10 04:03:31 -03002609 icsk->icsk_probes_out = 0;
Eric Dumazet6a408142019-01-17 11:23:33 -08002610 icsk->icsk_rto = TCP_TIMEOUT_INIT;
Ilpo Järvinen0b6a05c2009-09-15 01:30:10 -07002611 tp->snd_ssthresh = TCP_INFINITE_SSTHRESH;
Eric Dumazet3a9a57f2019-01-17 11:23:37 -08002612 tp->snd_cwnd = TCP_INIT_CWND;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002613 tp->snd_cwnd_cnt = 0;
Eric Dumazet1fdf4752009-11-30 12:53:30 -08002614 tp->window_clamp = 0;
Yuchung Chenge21db6f2018-04-17 23:18:48 -07002615 tp->delivered_ce = 0;
Arnaldo Carvalho de Melo6687e982005-08-10 04:03:31 -03002616 tcp_set_ca_state(sk, TCP_CA_Open);
Yousuk Seungd4761752017-12-07 13:41:34 -08002617 tp->is_sack_reneg = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002618 tcp_clear_retrans(tp);
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07002619 inet_csk_delack_init(sk);
Wei Wang499350a2017-05-18 11:22:33 -07002620 /* Initialize rcv_mss to TCP_MIN_MSS to avoid division by 0
2621 * issue in __tcp_select_window()
2622 */
2623 icsk->icsk_ack.rcv_mss = TCP_MIN_MSS;
Srinivas Ajib40b4f72007-05-03 17:32:28 -07002624 memset(&tp->rx_opt, 0, sizeof(tp->rx_opt));
Linus Torvalds1da177e2005-04-16 15:20:36 -07002625 __sk_dst_reset(sk);
WANG Congd747a7a2017-06-24 23:50:30 -07002626 dst_release(sk->sk_rx_dst);
2627 sk->sk_rx_dst = NULL;
Eric Dumazet17c30602017-04-08 08:07:33 -07002628 tcp_saved_syn_free(tp);
Eric Dumazet5d9f4262018-05-17 14:47:26 -07002629 tp->compressed_ack = 0;
Wei Wangba113c32018-07-31 17:46:21 -07002630 tp->bytes_sent = 0;
Christoph Paasche858faf2019-07-06 16:13:07 -07002631 tp->bytes_acked = 0;
2632 tp->bytes_received = 0;
Wei Wangfb31c9b2018-07-31 17:46:22 -07002633 tp->bytes_retrans = 0;
Yuchung Cheng77881742018-08-29 14:53:56 -07002634 tp->duplicate_sack[0].start_seq = 0;
2635 tp->duplicate_sack[0].end_seq = 0;
Wei Wang7e10b652018-07-31 17:46:23 -07002636 tp->dsack_dups = 0;
Wei Wang7ec65372018-07-31 17:46:24 -07002637 tp->reord_seen = 0;
Eric Dumazet5c701542019-01-17 11:23:39 -08002638 tp->retrans_out = 0;
2639 tp->sacked_out = 0;
2640 tp->tlp_high_seq = 0;
2641 tp->last_oow_ack_time = 0;
Eric Dumazet6cda8b72019-01-17 11:23:40 -08002642 /* There's a bubble in the pipe until at least the first ACK. */
2643 tp->app_limited = ~0U;
Eric Dumazet792c4352019-01-17 11:23:41 -08002644 tp->rack.mstamp = 0;
2645 tp->rack.advanced = 0;
2646 tp->rack.reo_wnd_steps = 1;
2647 tp->rack.last_delivered = 0;
2648 tp->rack.reo_wnd_persist = 0;
2649 tp->rack.dsack_seen = 0;
Eric Dumazet6bcdc402019-01-17 11:23:42 -08002650 tp->syn_data_acked = 0;
2651 tp->rx_opt.saw_tstamp = 0;
2652 tp->rx_opt.dsack = 0;
2653 tp->rx_opt.num_sacks = 0;
Thomas Higdonf9af2db2019-09-13 23:23:34 +00002654 tp->rcv_ooopack = 0;
Eric Dumazet6cda8b72019-01-17 11:23:40 -08002655
Linus Torvalds1da177e2005-04-16 15:20:36 -07002656
Wei Wang7db92362017-03-01 13:29:48 -08002657 /* Clean up fastopen related fields */
2658 tcp_free_fastopen_req(tp);
2659 inet->defer_connect = 0;
2660
Eric Dumazetc720c7e82009-10-15 06:30:45 +00002661 WARN_ON(inet->inet_num && !icsk->icsk_bind_hash);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002662
Li RongQing9b42d552018-01-26 16:40:41 +08002663 if (sk->sk_frag.page) {
2664 put_page(sk->sk_frag.page);
2665 sk->sk_frag.page = NULL;
2666 sk->sk_frag.offset = 0;
2667 }
2668
Linus Torvalds1da177e2005-04-16 15:20:36 -07002669 sk->sk_error_report(sk);
YueHaibinga01512b2018-08-03 16:28:48 +08002670 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002671}
Eric Dumazet4bc2f182010-07-09 21:22:10 +00002672EXPORT_SYMBOL(tcp_disconnect);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002673
Eric Dumazeta2a385d2012-05-16 23:15:34 +00002674static inline bool tcp_can_repair_sock(const struct sock *sk)
Pavel Emelyanovee995282012-04-19 03:40:39 +00002675{
Eric W. Biederman52e804c2012-11-16 03:03:05 +00002676 return ns_capable(sock_net(sk)->user_ns, CAP_NET_ADMIN) &&
Andrey Vagin319b0532016-11-14 18:15:14 -08002677 (sk->sk_state != TCP_LISTEN);
Pavel Emelyanovee995282012-04-19 03:40:39 +00002678}
2679
Andrey Vaginb1ed4c42016-06-27 15:33:56 -07002680static int tcp_repair_set_window(struct tcp_sock *tp, char __user *optbuf, int len)
2681{
2682 struct tcp_repair_window opt;
2683
2684 if (!tp->repair)
2685 return -EPERM;
2686
2687 if (len != sizeof(opt))
2688 return -EINVAL;
2689
2690 if (copy_from_user(&opt, optbuf, sizeof(opt)))
2691 return -EFAULT;
2692
2693 if (opt.max_window < opt.snd_wnd)
2694 return -EINVAL;
2695
2696 if (after(opt.snd_wl1, tp->rcv_nxt + opt.rcv_wnd))
2697 return -EINVAL;
2698
2699 if (after(opt.rcv_wup, tp->rcv_nxt))
2700 return -EINVAL;
2701
2702 tp->snd_wl1 = opt.snd_wl1;
2703 tp->snd_wnd = opt.snd_wnd;
2704 tp->max_window = opt.max_window;
2705
2706 tp->rcv_wnd = opt.rcv_wnd;
2707 tp->rcv_wup = opt.rcv_wup;
2708
2709 return 0;
2710}
2711
Douglas Caetano dos Santos15e56512017-05-26 14:28:00 -03002712static int tcp_repair_options_est(struct sock *sk,
Pavel Emelyanovde248a72012-04-25 23:43:04 +00002713 struct tcp_repair_opt __user *optbuf, unsigned int len)
Pavel Emelyanovb139ba42012-04-19 03:41:57 +00002714{
Douglas Caetano dos Santos15e56512017-05-26 14:28:00 -03002715 struct tcp_sock *tp = tcp_sk(sk);
Pavel Emelyanovde248a72012-04-25 23:43:04 +00002716 struct tcp_repair_opt opt;
Pavel Emelyanovb139ba42012-04-19 03:41:57 +00002717
Pavel Emelyanovde248a72012-04-25 23:43:04 +00002718 while (len >= sizeof(opt)) {
2719 if (copy_from_user(&opt, optbuf, sizeof(opt)))
Pavel Emelyanovb139ba42012-04-19 03:41:57 +00002720 return -EFAULT;
2721
2722 optbuf++;
Pavel Emelyanovde248a72012-04-25 23:43:04 +00002723 len -= sizeof(opt);
Pavel Emelyanovb139ba42012-04-19 03:41:57 +00002724
Pavel Emelyanovde248a72012-04-25 23:43:04 +00002725 switch (opt.opt_code) {
2726 case TCPOPT_MSS:
2727 tp->rx_opt.mss_clamp = opt.opt_val;
Douglas Caetano dos Santos15e56512017-05-26 14:28:00 -03002728 tcp_mtup_init(sk);
Pavel Emelyanovb139ba42012-04-19 03:41:57 +00002729 break;
Pavel Emelyanovde248a72012-04-25 23:43:04 +00002730 case TCPOPT_WINDOW:
Andrey Vaginbc26ccd2012-09-19 09:40:00 +00002731 {
2732 u16 snd_wscale = opt.opt_val & 0xFFFF;
2733 u16 rcv_wscale = opt.opt_val >> 16;
Pavel Emelyanovb139ba42012-04-19 03:41:57 +00002734
Gao Feng589c49c2017-04-04 21:09:48 +08002735 if (snd_wscale > TCP_MAX_WSCALE || rcv_wscale > TCP_MAX_WSCALE)
Andrey Vaginbc26ccd2012-09-19 09:40:00 +00002736 return -EFBIG;
2737
2738 tp->rx_opt.snd_wscale = snd_wscale;
2739 tp->rx_opt.rcv_wscale = rcv_wscale;
2740 tp->rx_opt.wscale_ok = 1;
2741 }
Pavel Emelyanovb139ba42012-04-19 03:41:57 +00002742 break;
Pavel Emelyanovb139ba42012-04-19 03:41:57 +00002743 case TCPOPT_SACK_PERM:
Pavel Emelyanovde248a72012-04-25 23:43:04 +00002744 if (opt.opt_val != 0)
2745 return -EINVAL;
2746
Pavel Emelyanovb139ba42012-04-19 03:41:57 +00002747 tp->rx_opt.sack_ok |= TCP_SACK_SEEN;
Pavel Emelyanovb139ba42012-04-19 03:41:57 +00002748 break;
2749 case TCPOPT_TIMESTAMP:
Pavel Emelyanovde248a72012-04-25 23:43:04 +00002750 if (opt.opt_val != 0)
2751 return -EINVAL;
2752
Pavel Emelyanovb139ba42012-04-19 03:41:57 +00002753 tp->rx_opt.tstamp_ok = 1;
2754 break;
2755 }
2756 }
2757
2758 return 0;
2759}
2760
Eric Dumazeta842fe12019-06-12 11:57:25 -07002761DEFINE_STATIC_KEY_FALSE(tcp_tx_delay_enabled);
2762EXPORT_SYMBOL(tcp_tx_delay_enabled);
2763
2764static void tcp_enable_tx_delay(void)
2765{
2766 if (!static_branch_unlikely(&tcp_tx_delay_enabled)) {
2767 static int __tcp_tx_delay_enabled = 0;
2768
2769 if (cmpxchg(&__tcp_tx_delay_enabled, 0, 1) == 0) {
2770 static_branch_enable(&tcp_tx_delay_enabled);
2771 pr_info("TCP_TX_DELAY enabled\n");
2772 }
2773 }
2774}
2775
Linus Torvalds1da177e2005-04-16 15:20:36 -07002776/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07002777 * Socket option code for TCP.
2778 */
Dmitry Mishin3fdadf72006-03-20 22:45:21 -08002779static int do_tcp_setsockopt(struct sock *sk, int level,
David S. Millerb7058842009-09-30 16:12:20 -07002780 int optname, char __user *optval, unsigned int optlen)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002781{
2782 struct tcp_sock *tp = tcp_sk(sk);
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07002783 struct inet_connection_sock *icsk = inet_csk(sk);
Nikolay Borisov1e579ca2016-02-03 09:46:56 +02002784 struct net *net = sock_net(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002785 int val;
2786 int err = 0;
2787
William Allen Simpsone56fb502009-12-02 18:19:30 +00002788 /* These are data/string values, all the others are ints */
2789 switch (optname) {
2790 case TCP_CONGESTION: {
Stephen Hemminger5f8ef482005-06-23 20:37:36 -07002791 char name[TCP_CA_NAME_MAX];
2792
2793 if (optlen < 1)
2794 return -EINVAL;
2795
2796 val = strncpy_from_user(name, optval,
Andrew Morton4fdb78d2009-10-01 15:02:20 -07002797 min_t(long, TCP_CA_NAME_MAX-1, optlen));
Stephen Hemminger5f8ef482005-06-23 20:37:36 -07002798 if (val < 0)
2799 return -EFAULT;
2800 name[val] = 0;
2801
2802 lock_sock(sk);
Eric Dumazet8d650cd2019-07-18 19:28:14 -07002803 err = tcp_set_congestion_control(sk, name, true, true,
2804 ns_capable(sock_net(sk)->user_ns,
2805 CAP_NET_ADMIN));
Stephen Hemminger5f8ef482005-06-23 20:37:36 -07002806 release_sock(sk);
2807 return err;
2808 }
Dave Watson734942c2017-06-14 11:37:14 -07002809 case TCP_ULP: {
2810 char name[TCP_ULP_NAME_MAX];
2811
2812 if (optlen < 1)
2813 return -EINVAL;
2814
2815 val = strncpy_from_user(name, optval,
2816 min_t(long, TCP_ULP_NAME_MAX - 1,
2817 optlen));
2818 if (val < 0)
2819 return -EFAULT;
2820 name[val] = 0;
2821
2822 lock_sock(sk);
2823 err = tcp_set_ulp(sk, name);
2824 release_sock(sk);
2825 return err;
2826 }
Yuchung Cheng1fba70e2017-10-18 11:22:51 -07002827 case TCP_FASTOPEN_KEY: {
Jason Baron0f1ce022019-05-29 12:33:58 -04002828 __u8 key[TCP_FASTOPEN_KEY_BUF_LENGTH];
2829 __u8 *backup_key = NULL;
Yuchung Cheng1fba70e2017-10-18 11:22:51 -07002830
Jason Baron0f1ce022019-05-29 12:33:58 -04002831 /* Allow a backup key as well to facilitate key rotation
2832 * First key is the active one.
2833 */
2834 if (optlen != TCP_FASTOPEN_KEY_LENGTH &&
2835 optlen != TCP_FASTOPEN_KEY_BUF_LENGTH)
Yuchung Cheng1fba70e2017-10-18 11:22:51 -07002836 return -EINVAL;
2837
2838 if (copy_from_user(key, optval, optlen))
2839 return -EFAULT;
2840
Jason Baron0f1ce022019-05-29 12:33:58 -04002841 if (optlen == TCP_FASTOPEN_KEY_BUF_LENGTH)
2842 backup_key = key + TCP_FASTOPEN_KEY_LENGTH;
2843
Ard Biesheuvel438ac882019-06-19 23:46:28 +02002844 return tcp_fastopen_reset_cipher(net, sk, key, backup_key);
Yuchung Cheng1fba70e2017-10-18 11:22:51 -07002845 }
William Allen Simpsone56fb502009-12-02 18:19:30 +00002846 default:
2847 /* fallthru */
2848 break;
Joe Perchesccbd6a52010-05-14 10:58:26 +00002849 }
Stephen Hemminger5f8ef482005-06-23 20:37:36 -07002850
Linus Torvalds1da177e2005-04-16 15:20:36 -07002851 if (optlen < sizeof(int))
2852 return -EINVAL;
2853
2854 if (get_user(val, (int __user *)optval))
2855 return -EFAULT;
2856
2857 lock_sock(sk);
2858
2859 switch (optname) {
2860 case TCP_MAXSEG:
2861 /* Values greater than interface MTU won't take effect. However
2862 * at the point when this call is done we typically don't yet
Rohit Chavana777f712017-05-22 11:59:15 +05302863 * know which interface is going to be used
2864 */
Gao Fengcfc62d82017-03-21 09:28:03 +08002865 if (val && (val < TCP_MIN_MSS || val > MAX_TCP_WINDOW)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002866 err = -EINVAL;
2867 break;
2868 }
2869 tp->rx_opt.user_mss = val;
2870 break;
2871
2872 case TCP_NODELAY:
2873 if (val) {
2874 /* TCP_NODELAY is weaker than TCP_CORK, so that
2875 * this option on corked socket is remembered, but
2876 * it is not activated until cork is cleared.
2877 *
2878 * However, when TCP_NODELAY is set we make
2879 * an explicit push, which overrides even TCP_CORK
2880 * for currently queued segments.
2881 */
2882 tp->nonagle |= TCP_NAGLE_OFF|TCP_NAGLE_PUSH;
Ilpo Järvinen9e412ba2007-04-20 22:18:02 -07002883 tcp_push_pending_frames(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002884 } else {
2885 tp->nonagle &= ~TCP_NAGLE_OFF;
2886 }
2887 break;
2888
Andreas Petlund36e31b0a2010-02-18 02:47:01 +00002889 case TCP_THIN_LINEAR_TIMEOUTS:
2890 if (val < 0 || val > 1)
2891 err = -EINVAL;
2892 else
2893 tp->thin_lto = val;
2894 break;
2895
Andreas Petlund7e380172010-02-18 04:48:19 +00002896 case TCP_THIN_DUPACK:
2897 if (val < 0 || val > 1)
2898 err = -EINVAL;
Andreas Petlund7e380172010-02-18 04:48:19 +00002899 break;
2900
Pavel Emelyanovee995282012-04-19 03:40:39 +00002901 case TCP_REPAIR:
2902 if (!tcp_can_repair_sock(sk))
2903 err = -EPERM;
Stefan Baranoff31048d72018-07-15 11:36:37 -04002904 else if (val == TCP_REPAIR_ON) {
Pavel Emelyanovee995282012-04-19 03:40:39 +00002905 tp->repair = 1;
2906 sk->sk_reuse = SK_FORCE_REUSE;
2907 tp->repair_queue = TCP_NO_QUEUE;
Stefan Baranoff31048d72018-07-15 11:36:37 -04002908 } else if (val == TCP_REPAIR_OFF) {
Pavel Emelyanovee995282012-04-19 03:40:39 +00002909 tp->repair = 0;
2910 sk->sk_reuse = SK_NO_REUSE;
2911 tcp_send_window_probe(sk);
Stefan Baranoff31048d72018-07-15 11:36:37 -04002912 } else if (val == TCP_REPAIR_OFF_NO_WP) {
2913 tp->repair = 0;
2914 sk->sk_reuse = SK_NO_REUSE;
Pavel Emelyanovee995282012-04-19 03:40:39 +00002915 } else
2916 err = -EINVAL;
2917
2918 break;
2919
2920 case TCP_REPAIR_QUEUE:
2921 if (!tp->repair)
2922 err = -EPERM;
Eric Dumazetbf2acc92018-04-29 18:55:20 -07002923 else if ((unsigned int)val < TCP_QUEUES_NR)
Pavel Emelyanovee995282012-04-19 03:40:39 +00002924 tp->repair_queue = val;
2925 else
2926 err = -EINVAL;
2927 break;
2928
2929 case TCP_QUEUE_SEQ:
2930 if (sk->sk_state != TCP_CLOSE)
2931 err = -EPERM;
2932 else if (tp->repair_queue == TCP_SEND_QUEUE)
2933 tp->write_seq = val;
2934 else if (tp->repair_queue == TCP_RECV_QUEUE)
2935 tp->rcv_nxt = val;
2936 else
2937 err = -EINVAL;
2938 break;
2939
Pavel Emelyanovb139ba42012-04-19 03:41:57 +00002940 case TCP_REPAIR_OPTIONS:
2941 if (!tp->repair)
2942 err = -EINVAL;
2943 else if (sk->sk_state == TCP_ESTABLISHED)
Douglas Caetano dos Santos15e56512017-05-26 14:28:00 -03002944 err = tcp_repair_options_est(sk,
Pavel Emelyanovde248a72012-04-25 23:43:04 +00002945 (struct tcp_repair_opt __user *)optval,
2946 optlen);
Pavel Emelyanovb139ba42012-04-19 03:41:57 +00002947 else
2948 err = -EPERM;
2949 break;
2950
Linus Torvalds1da177e2005-04-16 15:20:36 -07002951 case TCP_CORK:
2952 /* When set indicates to always queue non-full frames.
2953 * Later the user clears this option and we transmit
2954 * any pending partial frames in the queue. This is
2955 * meant to be used alongside sendfile() to get properly
2956 * filled frames when the user (for example) must write
2957 * out headers with a write() call first and then use
2958 * sendfile to send out the data parts.
2959 *
2960 * TCP_CORK can be set together with TCP_NODELAY and it is
2961 * stronger than TCP_NODELAY.
2962 */
2963 if (val) {
2964 tp->nonagle |= TCP_NAGLE_CORK;
2965 } else {
2966 tp->nonagle &= ~TCP_NAGLE_CORK;
2967 if (tp->nonagle&TCP_NAGLE_OFF)
2968 tp->nonagle |= TCP_NAGLE_PUSH;
Ilpo Järvinen9e412ba2007-04-20 22:18:02 -07002969 tcp_push_pending_frames(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002970 }
2971 break;
2972
2973 case TCP_KEEPIDLE:
2974 if (val < 1 || val > MAX_TCP_KEEPIDLE)
2975 err = -EINVAL;
2976 else {
2977 tp->keepalive_time = val * HZ;
2978 if (sock_flag(sk, SOCK_KEEPOPEN) &&
2979 !((1 << sk->sk_state) &
2980 (TCPF_CLOSE | TCPF_LISTEN))) {
Flavio Leitner6c37e5d2010-04-26 18:33:27 +00002981 u32 elapsed = keepalive_time_elapsed(tp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002982 if (tp->keepalive_time > elapsed)
2983 elapsed = tp->keepalive_time - elapsed;
2984 else
2985 elapsed = 0;
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07002986 inet_csk_reset_keepalive_timer(sk, elapsed);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002987 }
2988 }
2989 break;
2990 case TCP_KEEPINTVL:
2991 if (val < 1 || val > MAX_TCP_KEEPINTVL)
2992 err = -EINVAL;
2993 else
2994 tp->keepalive_intvl = val * HZ;
2995 break;
2996 case TCP_KEEPCNT:
2997 if (val < 1 || val > MAX_TCP_KEEPCNT)
2998 err = -EINVAL;
2999 else
3000 tp->keepalive_probes = val;
3001 break;
3002 case TCP_SYNCNT:
3003 if (val < 1 || val > MAX_TCP_SYNCNT)
3004 err = -EINVAL;
3005 else
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07003006 icsk->icsk_syn_retries = val;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003007 break;
3008
Eric Dumazetcd8ae852015-05-03 21:34:46 -07003009 case TCP_SAVE_SYN:
3010 if (val < 0 || val > 1)
3011 err = -EINVAL;
3012 else
3013 tp->save_syn = val;
3014 break;
3015
Linus Torvalds1da177e2005-04-16 15:20:36 -07003016 case TCP_LINGER2:
3017 if (val < 0)
3018 tp->linger2 = -1;
Nikolay Borisov1e579ca2016-02-03 09:46:56 +02003019 else if (val > net->ipv4.sysctl_tcp_fin_timeout / HZ)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003020 tp->linger2 = 0;
3021 else
3022 tp->linger2 = val * HZ;
3023 break;
3024
3025 case TCP_DEFER_ACCEPT:
Julian Anastasovb103cf32009-10-19 10:10:40 +00003026 /* Translate value in seconds to number of retransmits */
3027 icsk->icsk_accept_queue.rskq_defer_accept =
3028 secs_to_retrans(val, TCP_TIMEOUT_INIT / HZ,
3029 TCP_RTO_MAX / HZ);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003030 break;
3031
3032 case TCP_WINDOW_CLAMP:
3033 if (!val) {
3034 if (sk->sk_state != TCP_CLOSE) {
3035 err = -EINVAL;
3036 break;
3037 }
3038 tp->window_clamp = 0;
3039 } else
3040 tp->window_clamp = val < SOCK_MIN_RCVBUF / 2 ?
3041 SOCK_MIN_RCVBUF / 2 : val;
3042 break;
3043
3044 case TCP_QUICKACK:
3045 if (!val) {
Wei Wang31954cd2019-01-25 10:53:19 -08003046 inet_csk_enter_pingpong_mode(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003047 } else {
Wei Wang31954cd2019-01-25 10:53:19 -08003048 inet_csk_exit_pingpong_mode(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003049 if ((1 << sk->sk_state) &
3050 (TCPF_ESTABLISHED | TCPF_CLOSE_WAIT) &&
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07003051 inet_csk_ack_scheduled(sk)) {
3052 icsk->icsk_ack.pending |= ICSK_ACK_PUSHED;
Chris Leech0e4b4992006-05-23 18:00:16 -07003053 tcp_cleanup_rbuf(sk, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003054 if (!(val & 1))
Wei Wang31954cd2019-01-25 10:53:19 -08003055 inet_csk_enter_pingpong_mode(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003056 }
3057 }
3058 break;
3059
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08003060#ifdef CONFIG_TCP_MD5SIG
3061 case TCP_MD5SIG:
Ivan Delalande8917a772017-06-15 18:07:07 -07003062 case TCP_MD5SIG_EXT:
Eric Dumazet72123032018-04-11 14:36:28 -07003063 if ((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN))
3064 err = tp->af_specific->md5_parse(sk, optname, optval, optlen);
3065 else
3066 err = -EINVAL;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08003067 break;
3068#endif
Jerry Chudca43c72010-08-27 19:13:28 +00003069 case TCP_USER_TIMEOUT:
Yuchung Chengb2482302014-09-29 13:20:38 -07003070 /* Cap the max time in ms TCP will retry or probe the window
Jerry Chudca43c72010-08-27 19:13:28 +00003071 * before giving up and aborting (ETIMEDOUT) a connection.
3072 */
Hangbin Liu42493572012-07-26 22:52:21 +00003073 if (val < 0)
3074 err = -EINVAL;
3075 else
Jon Maxwell9bcc66e2018-07-19 11:14:42 +10003076 icsk->icsk_user_timeout = val;
Jerry Chudca43c72010-08-27 19:13:28 +00003077 break;
Jerry Chu83368862012-08-31 12:29:12 +00003078
3079 case TCP_FASTOPEN:
3080 if (val >= 0 && ((1 << sk->sk_state) & (TCPF_CLOSE |
Christoph Paaschdfea2aa2015-06-18 09:15:34 -07003081 TCPF_LISTEN))) {
Haishuang Yan43713842017-09-27 11:35:42 +08003082 tcp_fastopen_init_key_once(net);
Christoph Paaschdfea2aa2015-06-18 09:15:34 -07003083
Eric Dumazet0536fcc2015-09-29 07:42:52 -07003084 fastopen_queue_tune(sk, val);
Christoph Paaschdfea2aa2015-06-18 09:15:34 -07003085 } else {
Jerry Chu83368862012-08-31 12:29:12 +00003086 err = -EINVAL;
Christoph Paaschdfea2aa2015-06-18 09:15:34 -07003087 }
Jerry Chu83368862012-08-31 12:29:12 +00003088 break;
Wei Wang19f6d3f2017-01-23 10:59:22 -08003089 case TCP_FASTOPEN_CONNECT:
3090 if (val > 1 || val < 0) {
3091 err = -EINVAL;
Haishuang Yane1cfcbe2017-09-27 11:35:40 +08003092 } else if (net->ipv4.sysctl_tcp_fastopen & TFO_CLIENT_ENABLE) {
Wei Wang19f6d3f2017-01-23 10:59:22 -08003093 if (sk->sk_state == TCP_CLOSE)
3094 tp->fastopen_connect = val;
3095 else
3096 err = -EINVAL;
3097 } else {
3098 err = -EOPNOTSUPP;
3099 }
3100 break;
Christoph Paasch71c02372017-10-23 13:22:23 -07003101 case TCP_FASTOPEN_NO_COOKIE:
3102 if (val > 1 || val < 0)
3103 err = -EINVAL;
3104 else if (!((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN)))
3105 err = -EINVAL;
3106 else
3107 tp->fastopen_no_cookie = val;
3108 break;
Andrey Vagin93be6ce2013-02-11 05:50:18 +00003109 case TCP_TIMESTAMP:
3110 if (!tp->repair)
3111 err = -EPERM;
3112 else
Eric Dumazet9a568de2017-05-16 14:00:14 -07003113 tp->tsoffset = val - tcp_time_stamp_raw();
Andrey Vagin93be6ce2013-02-11 05:50:18 +00003114 break;
Andrey Vaginb1ed4c42016-06-27 15:33:56 -07003115 case TCP_REPAIR_WINDOW:
3116 err = tcp_repair_set_window(tp, optval, optlen);
3117 break;
Eric Dumazetc9bee3b72013-07-22 20:27:07 -07003118 case TCP_NOTSENT_LOWAT:
3119 tp->notsent_lowat = val;
3120 sk->sk_write_space(sk);
3121 break;
Soheil Hassas Yeganehb75eba72018-05-01 15:39:15 -04003122 case TCP_INQ:
3123 if (val > 1 || val < 0)
3124 err = -EINVAL;
3125 else
3126 tp->recvmsg_inq = val;
3127 break;
Eric Dumazeta842fe12019-06-12 11:57:25 -07003128 case TCP_TX_DELAY:
3129 if (val)
3130 tcp_enable_tx_delay();
3131 tp->tcp_tx_delay = val;
3132 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003133 default:
3134 err = -ENOPROTOOPT;
3135 break;
Stephen Hemminger3ff50b72007-04-20 17:09:22 -07003136 }
3137
Linus Torvalds1da177e2005-04-16 15:20:36 -07003138 release_sock(sk);
3139 return err;
3140}
3141
Dmitry Mishin3fdadf72006-03-20 22:45:21 -08003142int tcp_setsockopt(struct sock *sk, int level, int optname, char __user *optval,
David S. Millerb7058842009-09-30 16:12:20 -07003143 unsigned int optlen)
Dmitry Mishin3fdadf72006-03-20 22:45:21 -08003144{
Eric Dumazetcf533ea2011-10-21 05:22:42 -04003145 const struct inet_connection_sock *icsk = inet_csk(sk);
Dmitry Mishin3fdadf72006-03-20 22:45:21 -08003146
3147 if (level != SOL_TCP)
3148 return icsk->icsk_af_ops->setsockopt(sk, level, optname,
3149 optval, optlen);
3150 return do_tcp_setsockopt(sk, level, optname, optval, optlen);
3151}
Eric Dumazet4bc2f182010-07-09 21:22:10 +00003152EXPORT_SYMBOL(tcp_setsockopt);
Dmitry Mishin3fdadf72006-03-20 22:45:21 -08003153
3154#ifdef CONFIG_COMPAT
Arnaldo Carvalho de Melo543d9cf2006-03-20 22:48:35 -08003155int compat_tcp_setsockopt(struct sock *sk, int level, int optname,
David S. Millerb7058842009-09-30 16:12:20 -07003156 char __user *optval, unsigned int optlen)
Dmitry Mishin3fdadf72006-03-20 22:45:21 -08003157{
Arnaldo Carvalho de Melodec73ff2006-03-20 22:46:16 -08003158 if (level != SOL_TCP)
3159 return inet_csk_compat_setsockopt(sk, level, optname,
3160 optval, optlen);
Dmitry Mishin3fdadf72006-03-20 22:45:21 -08003161 return do_tcp_setsockopt(sk, level, optname, optval, optlen);
3162}
Arnaldo Carvalho de Melo543d9cf2006-03-20 22:48:35 -08003163EXPORT_SYMBOL(compat_tcp_setsockopt);
Dmitry Mishin3fdadf72006-03-20 22:45:21 -08003164#endif
3165
Francis Yanefd90172016-11-27 23:07:17 -08003166static void tcp_get_info_chrono_stats(const struct tcp_sock *tp,
3167 struct tcp_info *info)
3168{
3169 u64 stats[__TCP_CHRONO_MAX], total = 0;
3170 enum tcp_chrono i;
3171
3172 for (i = TCP_CHRONO_BUSY; i < __TCP_CHRONO_MAX; ++i) {
3173 stats[i] = tp->chrono_stat[i - 1];
3174 if (i == tp->chrono_type)
Eric Dumazet628174c2017-05-16 14:00:09 -07003175 stats[i] += tcp_jiffies32 - tp->chrono_start;
Francis Yanefd90172016-11-27 23:07:17 -08003176 stats[i] *= USEC_PER_SEC / HZ;
3177 total += stats[i];
3178 }
3179
3180 info->tcpi_busy_time = total;
3181 info->tcpi_rwnd_limited = stats[TCP_CHRONO_RWND_LIMITED];
3182 info->tcpi_sndbuf_limited = stats[TCP_CHRONO_SNDBUF_LIMITED];
3183}
3184
Linus Torvalds1da177e2005-04-16 15:20:36 -07003185/* Return information about state of tcp endpoint in API format. */
Eric Dumazet0df48c22015-04-28 15:28:17 -07003186void tcp_get_info(struct sock *sk, struct tcp_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003187{
Craig Gallek35ac8382015-06-15 11:26:20 -04003188 const struct tcp_sock *tp = tcp_sk(sk); /* iff sk_type == SOCK_STREAM */
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07003189 const struct inet_connection_sock *icsk = inet_csk(sk);
Eric Dumazet76a9ebe2018-10-15 09:37:53 -07003190 unsigned long rate;
Wei Wang02635982017-07-28 10:28:20 -07003191 u32 now;
Eric Dumazetff5d7492016-01-27 10:52:43 -08003192 u64 rate64;
Eric Dumazet67db3e42016-11-04 11:54:32 -07003193 bool slow;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003194
3195 memset(info, 0, sizeof(*info));
Craig Gallek35ac8382015-06-15 11:26:20 -04003196 if (sk->sk_type != SOCK_STREAM)
3197 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003198
Yafang Shao986ffdf2017-12-20 11:12:52 +08003199 info->tcpi_state = inet_sk_state_load(sk);
Eric Dumazet00fd38d2015-11-12 08:43:18 -08003200
Eric Dumazetccbf3bf2016-11-04 11:54:31 -07003201 /* Report meaningful fields for all TCP states, including listeners */
3202 rate = READ_ONCE(sk->sk_pacing_rate);
Eric Dumazet76a9ebe2018-10-15 09:37:53 -07003203 rate64 = (rate != ~0UL) ? rate : ~0ULL;
Eric Dumazetf522a5f2016-11-09 11:24:22 -08003204 info->tcpi_pacing_rate = rate64;
Eric Dumazetccbf3bf2016-11-04 11:54:31 -07003205
3206 rate = READ_ONCE(sk->sk_max_pacing_rate);
Eric Dumazet76a9ebe2018-10-15 09:37:53 -07003207 rate64 = (rate != ~0UL) ? rate : ~0ULL;
Eric Dumazetf522a5f2016-11-09 11:24:22 -08003208 info->tcpi_max_pacing_rate = rate64;
Eric Dumazetccbf3bf2016-11-04 11:54:31 -07003209
3210 info->tcpi_reordering = tp->reordering;
3211 info->tcpi_snd_cwnd = tp->snd_cwnd;
3212
3213 if (info->tcpi_state == TCP_LISTEN) {
3214 /* listeners aliased fields :
3215 * tcpi_unacked -> Number of children ready for accept()
3216 * tcpi_sacked -> max backlog
3217 */
3218 info->tcpi_unacked = sk->sk_ack_backlog;
3219 info->tcpi_sacked = sk->sk_max_ack_backlog;
3220 return;
3221 }
Eric Dumazetb369e7f2017-01-09 10:29:27 -08003222
3223 slow = lock_sock_fast(sk);
3224
Arnaldo Carvalho de Melo6687e982005-08-10 04:03:31 -03003225 info->tcpi_ca_state = icsk->icsk_ca_state;
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07003226 info->tcpi_retransmits = icsk->icsk_retransmits;
Arnaldo Carvalho de Melo6687e982005-08-10 04:03:31 -03003227 info->tcpi_probes = icsk->icsk_probes_out;
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07003228 info->tcpi_backoff = icsk->icsk_backoff;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003229
3230 if (tp->rx_opt.tstamp_ok)
3231 info->tcpi_options |= TCPI_OPT_TIMESTAMPS;
Ilpo Järvinene60402d2007-08-09 15:14:46 +03003232 if (tcp_is_sack(tp))
Linus Torvalds1da177e2005-04-16 15:20:36 -07003233 info->tcpi_options |= TCPI_OPT_SACK;
3234 if (tp->rx_opt.wscale_ok) {
3235 info->tcpi_options |= TCPI_OPT_WSCALE;
3236 info->tcpi_snd_wscale = tp->rx_opt.snd_wscale;
3237 info->tcpi_rcv_wscale = tp->rx_opt.rcv_wscale;
YOSHIFUJI Hideakie905a9e2007-02-09 23:24:47 +09003238 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07003239
Eric Dumazetb5c56932011-10-03 14:01:21 -04003240 if (tp->ecn_flags & TCP_ECN_OK)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003241 info->tcpi_options |= TCPI_OPT_ECN;
Eric Dumazetb5c56932011-10-03 14:01:21 -04003242 if (tp->ecn_flags & TCP_ECN_SEEN)
3243 info->tcpi_options |= TCPI_OPT_ECN_SEEN;
Yuchung Cheng6f736012012-10-19 15:14:44 +00003244 if (tp->syn_data_acked)
3245 info->tcpi_options |= TCPI_OPT_SYN_DATA;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003246
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07003247 info->tcpi_rto = jiffies_to_usecs(icsk->icsk_rto);
3248 info->tcpi_ato = jiffies_to_usecs(icsk->icsk_ack.ato);
David S. Millerc1b4a7e2005-07-05 15:24:38 -07003249 info->tcpi_snd_mss = tp->mss_cache;
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07003250 info->tcpi_rcv_mss = icsk->icsk_ack.rcv_mss;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003251
Eric Dumazetccbf3bf2016-11-04 11:54:31 -07003252 info->tcpi_unacked = tp->packets_out;
3253 info->tcpi_sacked = tp->sacked_out;
3254
Linus Torvalds1da177e2005-04-16 15:20:36 -07003255 info->tcpi_lost = tp->lost_out;
3256 info->tcpi_retrans = tp->retrans_out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003257
Eric Dumazetd635fbe2017-05-16 14:00:03 -07003258 now = tcp_jiffies32;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003259 info->tcpi_last_data_sent = jiffies_to_msecs(now - tp->lsndtime);
Arnaldo Carvalho de Melo463c84b2005-08-09 20:10:42 -07003260 info->tcpi_last_data_recv = jiffies_to_msecs(now - icsk->icsk_ack.lrcvtime);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003261 info->tcpi_last_ack_recv = jiffies_to_msecs(now - tp->rcv_tstamp);
3262
Arnaldo Carvalho de Melod83d8462005-12-13 23:26:10 -08003263 info->tcpi_pmtu = icsk->icsk_pmtu_cookie;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003264 info->tcpi_rcv_ssthresh = tp->rcv_ssthresh;
Eric Dumazet740b0f12014-02-26 14:02:48 -08003265 info->tcpi_rtt = tp->srtt_us >> 3;
3266 info->tcpi_rttvar = tp->mdev_us >> 2;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003267 info->tcpi_snd_ssthresh = tp->snd_ssthresh;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003268 info->tcpi_advmss = tp->advmss;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003269
Eric Dumazet645f4c62017-04-25 10:15:41 -07003270 info->tcpi_rcv_rtt = tp->rcv_rtt_est.rtt_us >> 3;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003271 info->tcpi_rcv_space = tp->rcvq_space.space;
3272
3273 info->tcpi_total_retrans = tp->total_retrans;
Eric Dumazet977cb0e2014-02-13 14:27:40 -08003274
Eric Dumazetf522a5f2016-11-09 11:24:22 -08003275 info->tcpi_bytes_acked = tp->bytes_acked;
3276 info->tcpi_bytes_received = tp->bytes_received;
Eric Dumazet67db3e42016-11-04 11:54:32 -07003277 info->tcpi_notsent_bytes = max_t(int, 0, tp->write_seq - tp->snd_nxt);
Francis Yanefd90172016-11-27 23:07:17 -08003278 tcp_get_info_chrono_stats(tp, info);
Eric Dumazet67db3e42016-11-04 11:54:32 -07003279
Marcelo Ricardo Leitner2efd0552015-05-20 16:35:41 -07003280 info->tcpi_segs_out = tp->segs_out;
3281 info->tcpi_segs_in = tp->segs_in;
Eric Dumazetcd9b2662016-02-11 22:02:53 -08003282
Eric Dumazetcd9b2662016-02-11 22:02:53 -08003283 info->tcpi_min_rtt = tcp_min_rtt(tp);
Martin KaFai Laua44d6ea2016-03-14 10:52:15 -07003284 info->tcpi_data_segs_in = tp->data_segs_in;
3285 info->tcpi_data_segs_out = tp->data_segs_out;
Yuchung Chengeb8329e2016-09-19 23:39:16 -04003286
3287 info->tcpi_delivery_rate_app_limited = tp->rate_app_limited ? 1 : 0;
Wei Wang02635982017-07-28 10:28:20 -07003288 rate64 = tcp_compute_delivery_rate(tp);
3289 if (rate64)
Eric Dumazetf522a5f2016-11-09 11:24:22 -08003290 info->tcpi_delivery_rate = rate64;
Yuchung Chengfeb5f2e2018-04-17 23:18:49 -07003291 info->tcpi_delivered = tp->delivered;
3292 info->tcpi_delivered_ce = tp->delivered_ce;
Wei Wangba113c32018-07-31 17:46:21 -07003293 info->tcpi_bytes_sent = tp->bytes_sent;
Wei Wangfb31c9b2018-07-31 17:46:22 -07003294 info->tcpi_bytes_retrans = tp->bytes_retrans;
Wei Wang7e10b652018-07-31 17:46:23 -07003295 info->tcpi_dsack_dups = tp->dsack_dups;
Wei Wang7ec65372018-07-31 17:46:24 -07003296 info->tcpi_reord_seen = tp->reord_seen;
Thomas Higdonf9af2db2019-09-13 23:23:34 +00003297 info->tcpi_rcv_ooopack = tp->rcv_ooopack;
Thomas Higdon8f7baad7f2019-09-13 23:23:35 +00003298 info->tcpi_snd_wnd = tp->snd_wnd;
Eric Dumazetb369e7f2017-01-09 10:29:27 -08003299 unlock_sock_fast(sk, slow);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003300}
Linus Torvalds1da177e2005-04-16 15:20:36 -07003301EXPORT_SYMBOL_GPL(tcp_get_info);
3302
Wei Wang984988a2018-07-31 17:46:20 -07003303static size_t tcp_opt_stats_get_size(void)
3304{
3305 return
3306 nla_total_size_64bit(sizeof(u64)) + /* TCP_NLA_BUSY */
3307 nla_total_size_64bit(sizeof(u64)) + /* TCP_NLA_RWND_LIMITED */
3308 nla_total_size_64bit(sizeof(u64)) + /* TCP_NLA_SNDBUF_LIMITED */
3309 nla_total_size_64bit(sizeof(u64)) + /* TCP_NLA_DATA_SEGS_OUT */
3310 nla_total_size_64bit(sizeof(u64)) + /* TCP_NLA_TOTAL_RETRANS */
3311 nla_total_size_64bit(sizeof(u64)) + /* TCP_NLA_PACING_RATE */
3312 nla_total_size_64bit(sizeof(u64)) + /* TCP_NLA_DELIVERY_RATE */
3313 nla_total_size(sizeof(u32)) + /* TCP_NLA_SND_CWND */
3314 nla_total_size(sizeof(u32)) + /* TCP_NLA_REORDERING */
3315 nla_total_size(sizeof(u32)) + /* TCP_NLA_MIN_RTT */
3316 nla_total_size(sizeof(u8)) + /* TCP_NLA_RECUR_RETRANS */
3317 nla_total_size(sizeof(u8)) + /* TCP_NLA_DELIVERY_RATE_APP_LMT */
3318 nla_total_size(sizeof(u32)) + /* TCP_NLA_SNDQ_SIZE */
3319 nla_total_size(sizeof(u8)) + /* TCP_NLA_CA_STATE */
3320 nla_total_size(sizeof(u32)) + /* TCP_NLA_SND_SSTHRESH */
3321 nla_total_size(sizeof(u32)) + /* TCP_NLA_DELIVERED */
3322 nla_total_size(sizeof(u32)) + /* TCP_NLA_DELIVERED_CE */
Wei Wangba113c32018-07-31 17:46:21 -07003323 nla_total_size_64bit(sizeof(u64)) + /* TCP_NLA_BYTES_SENT */
Wei Wangfb31c9b2018-07-31 17:46:22 -07003324 nla_total_size_64bit(sizeof(u64)) + /* TCP_NLA_BYTES_RETRANS */
Wei Wang7e10b652018-07-31 17:46:23 -07003325 nla_total_size(sizeof(u32)) + /* TCP_NLA_DSACK_DUPS */
Wei Wang7ec65372018-07-31 17:46:24 -07003326 nla_total_size(sizeof(u32)) + /* TCP_NLA_REORD_SEEN */
Yousuk Seunge8bd8fc2018-11-15 16:44:12 -08003327 nla_total_size(sizeof(u32)) + /* TCP_NLA_SRTT */
Wei Wang984988a2018-07-31 17:46:20 -07003328 0;
3329}
3330
Francis Yan1c885802016-11-27 23:07:18 -08003331struct sk_buff *tcp_get_timestamping_opt_stats(const struct sock *sk)
3332{
3333 const struct tcp_sock *tp = tcp_sk(sk);
3334 struct sk_buff *stats;
3335 struct tcp_info info;
Eric Dumazet76a9ebe2018-10-15 09:37:53 -07003336 unsigned long rate;
Wei Wangbb7c19f2017-07-28 10:28:21 -07003337 u64 rate64;
Francis Yan1c885802016-11-27 23:07:18 -08003338
Wei Wang984988a2018-07-31 17:46:20 -07003339 stats = alloc_skb(tcp_opt_stats_get_size(), GFP_ATOMIC);
Francis Yan1c885802016-11-27 23:07:18 -08003340 if (!stats)
3341 return NULL;
3342
3343 tcp_get_info_chrono_stats(tp, &info);
3344 nla_put_u64_64bit(stats, TCP_NLA_BUSY,
3345 info.tcpi_busy_time, TCP_NLA_PAD);
3346 nla_put_u64_64bit(stats, TCP_NLA_RWND_LIMITED,
3347 info.tcpi_rwnd_limited, TCP_NLA_PAD);
3348 nla_put_u64_64bit(stats, TCP_NLA_SNDBUF_LIMITED,
3349 info.tcpi_sndbuf_limited, TCP_NLA_PAD);
Yuchung Cheng7e981022017-01-27 16:24:38 -08003350 nla_put_u64_64bit(stats, TCP_NLA_DATA_SEGS_OUT,
3351 tp->data_segs_out, TCP_NLA_PAD);
3352 nla_put_u64_64bit(stats, TCP_NLA_TOTAL_RETRANS,
3353 tp->total_retrans, TCP_NLA_PAD);
Wei Wangbb7c19f2017-07-28 10:28:21 -07003354
3355 rate = READ_ONCE(sk->sk_pacing_rate);
Eric Dumazet76a9ebe2018-10-15 09:37:53 -07003356 rate64 = (rate != ~0UL) ? rate : ~0ULL;
Wei Wangbb7c19f2017-07-28 10:28:21 -07003357 nla_put_u64_64bit(stats, TCP_NLA_PACING_RATE, rate64, TCP_NLA_PAD);
3358
3359 rate64 = tcp_compute_delivery_rate(tp);
3360 nla_put_u64_64bit(stats, TCP_NLA_DELIVERY_RATE, rate64, TCP_NLA_PAD);
3361
3362 nla_put_u32(stats, TCP_NLA_SND_CWND, tp->snd_cwnd);
3363 nla_put_u32(stats, TCP_NLA_REORDERING, tp->reordering);
3364 nla_put_u32(stats, TCP_NLA_MIN_RTT, tcp_min_rtt(tp));
3365
3366 nla_put_u8(stats, TCP_NLA_RECUR_RETRANS, inet_csk(sk)->icsk_retransmits);
3367 nla_put_u8(stats, TCP_NLA_DELIVERY_RATE_APP_LMT, !!tp->rate_app_limited);
Yousuk Seung7156d192018-03-16 10:51:07 -07003368 nla_put_u32(stats, TCP_NLA_SND_SSTHRESH, tp->snd_ssthresh);
Yuchung Chengfeb5f2e2018-04-17 23:18:49 -07003369 nla_put_u32(stats, TCP_NLA_DELIVERED, tp->delivered);
3370 nla_put_u32(stats, TCP_NLA_DELIVERED_CE, tp->delivered_ce);
Priyaranjan Jha87ecc952018-03-04 10:38:35 -08003371
3372 nla_put_u32(stats, TCP_NLA_SNDQ_SIZE, tp->write_seq - tp->snd_una);
Priyaranjan Jhabe631892018-03-04 10:38:36 -08003373 nla_put_u8(stats, TCP_NLA_CA_STATE, inet_csk(sk)->icsk_ca_state);
Yuchung Chengfeb5f2e2018-04-17 23:18:49 -07003374
Wei Wangba113c32018-07-31 17:46:21 -07003375 nla_put_u64_64bit(stats, TCP_NLA_BYTES_SENT, tp->bytes_sent,
3376 TCP_NLA_PAD);
Wei Wangfb31c9b2018-07-31 17:46:22 -07003377 nla_put_u64_64bit(stats, TCP_NLA_BYTES_RETRANS, tp->bytes_retrans,
3378 TCP_NLA_PAD);
Wei Wang7e10b652018-07-31 17:46:23 -07003379 nla_put_u32(stats, TCP_NLA_DSACK_DUPS, tp->dsack_dups);
Wei Wang7ec65372018-07-31 17:46:24 -07003380 nla_put_u32(stats, TCP_NLA_REORD_SEEN, tp->reord_seen);
Yousuk Seunge8bd8fc2018-11-15 16:44:12 -08003381 nla_put_u32(stats, TCP_NLA_SRTT, tp->srtt_us >> 3);
Wei Wangba113c32018-07-31 17:46:21 -07003382
Francis Yan1c885802016-11-27 23:07:18 -08003383 return stats;
3384}
3385
Dmitry Mishin3fdadf72006-03-20 22:45:21 -08003386static int do_tcp_getsockopt(struct sock *sk, int level,
3387 int optname, char __user *optval, int __user *optlen)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003388{
Arnaldo Carvalho de Melo295f7322005-08-09 20:11:56 -07003389 struct inet_connection_sock *icsk = inet_csk(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003390 struct tcp_sock *tp = tcp_sk(sk);
Nikolay Borisov6fa25162016-02-03 09:46:49 +02003391 struct net *net = sock_net(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003392 int val, len;
3393
Linus Torvalds1da177e2005-04-16 15:20:36 -07003394 if (get_user(len, optlen))
3395 return -EFAULT;
3396
3397 len = min_t(unsigned int, len, sizeof(int));
3398
3399 if (len < 0)
3400 return -EINVAL;
3401
3402 switch (optname) {
3403 case TCP_MAXSEG:
David S. Millerc1b4a7e2005-07-05 15:24:38 -07003404 val = tp->mss_cache;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003405 if (!val && ((1 << sk->sk_state) & (TCPF_CLOSE | TCPF_LISTEN)))
3406 val = tp->rx_opt.user_mss;
Pavel Emelyanov5e6a3ce2012-04-19 03:41:32 +00003407 if (tp->repair)
3408 val = tp->rx_opt.mss_clamp;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003409 break;
3410 case TCP_NODELAY:
3411 val = !!(tp->nonagle&TCP_NAGLE_OFF);
3412 break;
3413 case TCP_CORK:
3414 val = !!(tp->nonagle&TCP_NAGLE_CORK);
3415 break;
3416 case TCP_KEEPIDLE:
Eric Dumazetdf19a622009-08-28 23:48:54 -07003417 val = keepalive_time_when(tp) / HZ;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003418 break;
3419 case TCP_KEEPINTVL:
Eric Dumazetdf19a622009-08-28 23:48:54 -07003420 val = keepalive_intvl_when(tp) / HZ;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003421 break;
3422 case TCP_KEEPCNT:
Eric Dumazetdf19a622009-08-28 23:48:54 -07003423 val = keepalive_probes(tp);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003424 break;
3425 case TCP_SYNCNT:
Nikolay Borisov6fa25162016-02-03 09:46:49 +02003426 val = icsk->icsk_syn_retries ? : net->ipv4.sysctl_tcp_syn_retries;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003427 break;
3428 case TCP_LINGER2:
3429 val = tp->linger2;
3430 if (val >= 0)
Nikolay Borisov1e579ca2016-02-03 09:46:56 +02003431 val = (val ? : net->ipv4.sysctl_tcp_fin_timeout) / HZ;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003432 break;
3433 case TCP_DEFER_ACCEPT:
Julian Anastasovb103cf32009-10-19 10:10:40 +00003434 val = retrans_to_secs(icsk->icsk_accept_queue.rskq_defer_accept,
3435 TCP_TIMEOUT_INIT / HZ, TCP_RTO_MAX / HZ);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003436 break;
3437 case TCP_WINDOW_CLAMP:
3438 val = tp->window_clamp;
3439 break;
3440 case TCP_INFO: {
3441 struct tcp_info info;
3442
3443 if (get_user(len, optlen))
3444 return -EFAULT;
3445
3446 tcp_get_info(sk, &info);
3447
3448 len = min_t(unsigned int, len, sizeof(info));
3449 if (put_user(len, optlen))
3450 return -EFAULT;
3451 if (copy_to_user(optval, &info, len))
3452 return -EFAULT;
3453 return 0;
3454 }
Eric Dumazet6e9250f2015-04-28 16:23:49 -07003455 case TCP_CC_INFO: {
3456 const struct tcp_congestion_ops *ca_ops;
3457 union tcp_cc_info info;
3458 size_t sz = 0;
3459 int attr;
3460
3461 if (get_user(len, optlen))
3462 return -EFAULT;
3463
3464 ca_ops = icsk->icsk_ca_ops;
3465 if (ca_ops && ca_ops->get_info)
3466 sz = ca_ops->get_info(sk, ~0U, &attr, &info);
3467
3468 len = min_t(unsigned int, len, sz);
3469 if (put_user(len, optlen))
3470 return -EFAULT;
3471 if (copy_to_user(optval, &info, len))
3472 return -EFAULT;
3473 return 0;
3474 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07003475 case TCP_QUICKACK:
Wei Wang31954cd2019-01-25 10:53:19 -08003476 val = !inet_csk_in_pingpong_mode(sk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003477 break;
Stephen Hemminger5f8ef482005-06-23 20:37:36 -07003478
3479 case TCP_CONGESTION:
3480 if (get_user(len, optlen))
3481 return -EFAULT;
3482 len = min_t(unsigned int, len, TCP_CA_NAME_MAX);
3483 if (put_user(len, optlen))
3484 return -EFAULT;
Arnaldo Carvalho de Melo6687e982005-08-10 04:03:31 -03003485 if (copy_to_user(optval, icsk->icsk_ca_ops->name, len))
Stephen Hemminger5f8ef482005-06-23 20:37:36 -07003486 return -EFAULT;
3487 return 0;
William Allen Simpsone56fb502009-12-02 18:19:30 +00003488
Dave Watson734942c2017-06-14 11:37:14 -07003489 case TCP_ULP:
3490 if (get_user(len, optlen))
3491 return -EFAULT;
3492 len = min_t(unsigned int, len, TCP_ULP_NAME_MAX);
Dave Watsond97af302017-06-26 08:36:47 -07003493 if (!icsk->icsk_ulp_ops) {
3494 if (put_user(0, optlen))
3495 return -EFAULT;
3496 return 0;
3497 }
Dave Watson734942c2017-06-14 11:37:14 -07003498 if (put_user(len, optlen))
3499 return -EFAULT;
3500 if (copy_to_user(optval, icsk->icsk_ulp_ops->name, len))
3501 return -EFAULT;
3502 return 0;
3503
Yuchung Cheng1fba70e2017-10-18 11:22:51 -07003504 case TCP_FASTOPEN_KEY: {
Jason Baron0f1ce022019-05-29 12:33:58 -04003505 __u8 key[TCP_FASTOPEN_KEY_BUF_LENGTH];
Yuchung Cheng1fba70e2017-10-18 11:22:51 -07003506 struct tcp_fastopen_context *ctx;
Jason Baron0f1ce022019-05-29 12:33:58 -04003507 unsigned int key_len = 0;
Yuchung Cheng1fba70e2017-10-18 11:22:51 -07003508
3509 if (get_user(len, optlen))
3510 return -EFAULT;
3511
3512 rcu_read_lock();
3513 ctx = rcu_dereference(icsk->icsk_accept_queue.fastopenq.ctx);
Jason Baron0f1ce022019-05-29 12:33:58 -04003514 if (ctx) {
3515 key_len = tcp_fastopen_context_len(ctx) *
3516 TCP_FASTOPEN_KEY_LENGTH;
3517 memcpy(&key[0], &ctx->key[0], key_len);
3518 }
Yuchung Cheng1fba70e2017-10-18 11:22:51 -07003519 rcu_read_unlock();
3520
Jason Baron0f1ce022019-05-29 12:33:58 -04003521 len = min_t(unsigned int, len, key_len);
Yuchung Cheng1fba70e2017-10-18 11:22:51 -07003522 if (put_user(len, optlen))
3523 return -EFAULT;
3524 if (copy_to_user(optval, key, len))
3525 return -EFAULT;
3526 return 0;
3527 }
Josh Hunt3c0fef02010-07-30 13:49:35 +00003528 case TCP_THIN_LINEAR_TIMEOUTS:
3529 val = tp->thin_lto;
3530 break;
Yuchung Cheng4a7f6002017-01-12 22:11:41 -08003531
Josh Hunt3c0fef02010-07-30 13:49:35 +00003532 case TCP_THIN_DUPACK:
Yuchung Cheng4a7f6002017-01-12 22:11:41 -08003533 val = 0;
Josh Hunt3c0fef02010-07-30 13:49:35 +00003534 break;
Jerry Chudca43c72010-08-27 19:13:28 +00003535
Pavel Emelyanovee995282012-04-19 03:40:39 +00003536 case TCP_REPAIR:
3537 val = tp->repair;
3538 break;
3539
3540 case TCP_REPAIR_QUEUE:
3541 if (tp->repair)
3542 val = tp->repair_queue;
3543 else
3544 return -EINVAL;
3545 break;
3546
Andrey Vaginb1ed4c42016-06-27 15:33:56 -07003547 case TCP_REPAIR_WINDOW: {
3548 struct tcp_repair_window opt;
3549
3550 if (get_user(len, optlen))
3551 return -EFAULT;
3552
3553 if (len != sizeof(opt))
3554 return -EINVAL;
3555
3556 if (!tp->repair)
3557 return -EPERM;
3558
3559 opt.snd_wl1 = tp->snd_wl1;
3560 opt.snd_wnd = tp->snd_wnd;
3561 opt.max_window = tp->max_window;
3562 opt.rcv_wnd = tp->rcv_wnd;
3563 opt.rcv_wup = tp->rcv_wup;
3564
3565 if (copy_to_user(optval, &opt, len))
3566 return -EFAULT;
3567 return 0;
3568 }
Pavel Emelyanovee995282012-04-19 03:40:39 +00003569 case TCP_QUEUE_SEQ:
3570 if (tp->repair_queue == TCP_SEND_QUEUE)
3571 val = tp->write_seq;
3572 else if (tp->repair_queue == TCP_RECV_QUEUE)
3573 val = tp->rcv_nxt;
3574 else
3575 return -EINVAL;
3576 break;
3577
Jerry Chudca43c72010-08-27 19:13:28 +00003578 case TCP_USER_TIMEOUT:
Jon Maxwell9bcc66e2018-07-19 11:14:42 +10003579 val = icsk->icsk_user_timeout;
Jerry Chudca43c72010-08-27 19:13:28 +00003580 break;
Kenjiro Nakayama1536e282014-04-17 01:25:01 +09003581
3582 case TCP_FASTOPEN:
Eric Dumazet0536fcc2015-09-29 07:42:52 -07003583 val = icsk->icsk_accept_queue.fastopenq.max_qlen;
Kenjiro Nakayama1536e282014-04-17 01:25:01 +09003584 break;
3585
Wei Wang19f6d3f2017-01-23 10:59:22 -08003586 case TCP_FASTOPEN_CONNECT:
3587 val = tp->fastopen_connect;
3588 break;
3589
Christoph Paasch71c02372017-10-23 13:22:23 -07003590 case TCP_FASTOPEN_NO_COOKIE:
3591 val = tp->fastopen_no_cookie;
3592 break;
3593
Eric Dumazeta842fe12019-06-12 11:57:25 -07003594 case TCP_TX_DELAY:
3595 val = tp->tcp_tx_delay;
3596 break;
3597
Andrey Vagin93be6ce2013-02-11 05:50:18 +00003598 case TCP_TIMESTAMP:
Eric Dumazet9a568de2017-05-16 14:00:14 -07003599 val = tcp_time_stamp_raw() + tp->tsoffset;
Andrey Vagin93be6ce2013-02-11 05:50:18 +00003600 break;
Eric Dumazetc9bee3b72013-07-22 20:27:07 -07003601 case TCP_NOTSENT_LOWAT:
3602 val = tp->notsent_lowat;
3603 break;
Soheil Hassas Yeganehb75eba72018-05-01 15:39:15 -04003604 case TCP_INQ:
3605 val = tp->recvmsg_inq;
3606 break;
Eric Dumazetcd8ae852015-05-03 21:34:46 -07003607 case TCP_SAVE_SYN:
3608 val = tp->save_syn;
3609 break;
3610 case TCP_SAVED_SYN: {
3611 if (get_user(len, optlen))
3612 return -EFAULT;
3613
3614 lock_sock(sk);
3615 if (tp->saved_syn) {
Eric B Munsonaea09292015-05-18 14:35:58 -04003616 if (len < tp->saved_syn[0]) {
3617 if (put_user(tp->saved_syn[0], optlen)) {
3618 release_sock(sk);
3619 return -EFAULT;
3620 }
3621 release_sock(sk);
3622 return -EINVAL;
3623 }
3624 len = tp->saved_syn[0];
Eric Dumazetcd8ae852015-05-03 21:34:46 -07003625 if (put_user(len, optlen)) {
3626 release_sock(sk);
3627 return -EFAULT;
3628 }
3629 if (copy_to_user(optval, tp->saved_syn + 1, len)) {
3630 release_sock(sk);
3631 return -EFAULT;
3632 }
3633 tcp_saved_syn_free(tp);
3634 release_sock(sk);
3635 } else {
3636 release_sock(sk);
3637 len = 0;
3638 if (put_user(len, optlen))
3639 return -EFAULT;
3640 }
3641 return 0;
3642 }
Eric Dumazet05255b82018-04-27 08:58:08 -07003643#ifdef CONFIG_MMU
3644 case TCP_ZEROCOPY_RECEIVE: {
3645 struct tcp_zerocopy_receive zc;
3646 int err;
3647
3648 if (get_user(len, optlen))
3649 return -EFAULT;
3650 if (len != sizeof(zc))
3651 return -EINVAL;
3652 if (copy_from_user(&zc, optval, len))
3653 return -EFAULT;
3654 lock_sock(sk);
3655 err = tcp_zerocopy_receive(sk, &zc);
3656 release_sock(sk);
3657 if (!err && copy_to_user(optval, &zc, len))
3658 err = -EFAULT;
3659 return err;
3660 }
3661#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07003662 default:
3663 return -ENOPROTOOPT;
Stephen Hemminger3ff50b72007-04-20 17:09:22 -07003664 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07003665
3666 if (put_user(len, optlen))
3667 return -EFAULT;
3668 if (copy_to_user(optval, &val, len))
3669 return -EFAULT;
3670 return 0;
3671}
3672
Dmitry Mishin3fdadf72006-03-20 22:45:21 -08003673int tcp_getsockopt(struct sock *sk, int level, int optname, char __user *optval,
3674 int __user *optlen)
3675{
3676 struct inet_connection_sock *icsk = inet_csk(sk);
3677
3678 if (level != SOL_TCP)
3679 return icsk->icsk_af_ops->getsockopt(sk, level, optname,
3680 optval, optlen);
3681 return do_tcp_getsockopt(sk, level, optname, optval, optlen);
3682}
Eric Dumazet4bc2f182010-07-09 21:22:10 +00003683EXPORT_SYMBOL(tcp_getsockopt);
Dmitry Mishin3fdadf72006-03-20 22:45:21 -08003684
3685#ifdef CONFIG_COMPAT
Arnaldo Carvalho de Melo543d9cf2006-03-20 22:48:35 -08003686int compat_tcp_getsockopt(struct sock *sk, int level, int optname,
3687 char __user *optval, int __user *optlen)
Dmitry Mishin3fdadf72006-03-20 22:45:21 -08003688{
Arnaldo Carvalho de Melodec73ff2006-03-20 22:46:16 -08003689 if (level != SOL_TCP)
3690 return inet_csk_compat_getsockopt(sk, level, optname,
3691 optval, optlen);
Dmitry Mishin3fdadf72006-03-20 22:45:21 -08003692 return do_tcp_getsockopt(sk, level, optname, optval, optlen);
3693}
Arnaldo Carvalho de Melo543d9cf2006-03-20 22:48:35 -08003694EXPORT_SYMBOL(compat_tcp_getsockopt);
Dmitry Mishin3fdadf72006-03-20 22:45:21 -08003695#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -07003696
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08003697#ifdef CONFIG_TCP_MD5SIG
Eric Dumazet349ce992014-10-23 12:58:58 -07003698static DEFINE_PER_CPU(struct tcp_md5sig_pool, tcp_md5sig_pool);
Eric Dumazet71cea172013-05-20 06:52:26 +00003699static DEFINE_MUTEX(tcp_md5sig_mutex);
Eric Dumazet349ce992014-10-23 12:58:58 -07003700static bool tcp_md5sig_pool_populated = false;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08003701
Eric Dumazet71cea172013-05-20 06:52:26 +00003702static void __tcp_alloc_md5sig_pool(void)
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08003703{
Herbert Xucf80e0e2016-01-24 21:20:23 +08003704 struct crypto_ahash *hash;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08003705 int cpu;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08003706
Herbert Xucf80e0e2016-01-24 21:20:23 +08003707 hash = crypto_alloc_ahash("md5", 0, CRYPTO_ALG_ASYNC);
Linus Torvalds70477372016-03-17 11:22:54 -07003708 if (IS_ERR(hash))
Herbert Xucf80e0e2016-01-24 21:20:23 +08003709 return;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08003710
Herbert Xucf80e0e2016-01-24 21:20:23 +08003711 for_each_possible_cpu(cpu) {
Eric Dumazet19689e32016-06-27 18:51:53 +02003712 void *scratch = per_cpu(tcp_md5sig_pool, cpu).scratch;
Herbert Xucf80e0e2016-01-24 21:20:23 +08003713 struct ahash_request *req;
3714
Eric Dumazet19689e32016-06-27 18:51:53 +02003715 if (!scratch) {
3716 scratch = kmalloc_node(sizeof(union tcp_md5sum_block) +
3717 sizeof(struct tcphdr),
3718 GFP_KERNEL,
3719 cpu_to_node(cpu));
3720 if (!scratch)
3721 return;
3722 per_cpu(tcp_md5sig_pool, cpu).scratch = scratch;
3723 }
Herbert Xucf80e0e2016-01-24 21:20:23 +08003724 if (per_cpu(tcp_md5sig_pool, cpu).md5_req)
3725 continue;
3726
3727 req = ahash_request_alloc(hash, GFP_KERNEL);
3728 if (!req)
3729 return;
3730
3731 ahash_request_set_callback(req, 0, NULL, NULL);
3732
3733 per_cpu(tcp_md5sig_pool, cpu).md5_req = req;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08003734 }
Eric Dumazet349ce992014-10-23 12:58:58 -07003735 /* before setting tcp_md5sig_pool_populated, we must commit all writes
3736 * to memory. See smp_rmb() in tcp_get_md5sig_pool()
Eric Dumazet71cea172013-05-20 06:52:26 +00003737 */
3738 smp_wmb();
Eric Dumazet349ce992014-10-23 12:58:58 -07003739 tcp_md5sig_pool_populated = true;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08003740}
3741
Eric Dumazet71cea172013-05-20 06:52:26 +00003742bool tcp_alloc_md5sig_pool(void)
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08003743{
Eric Dumazet349ce992014-10-23 12:58:58 -07003744 if (unlikely(!tcp_md5sig_pool_populated)) {
Eric Dumazet71cea172013-05-20 06:52:26 +00003745 mutex_lock(&tcp_md5sig_mutex);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08003746
Eric Dumazet6015c712018-11-27 15:03:21 -08003747 if (!tcp_md5sig_pool_populated) {
Eric Dumazet71cea172013-05-20 06:52:26 +00003748 __tcp_alloc_md5sig_pool();
Eric Dumazet6015c712018-11-27 15:03:21 -08003749 if (tcp_md5sig_pool_populated)
Eric Dumazet921f9a02019-02-26 09:49:11 -08003750 static_branch_inc(&tcp_md5_needed);
Eric Dumazet6015c712018-11-27 15:03:21 -08003751 }
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08003752
Eric Dumazet71cea172013-05-20 06:52:26 +00003753 mutex_unlock(&tcp_md5sig_mutex);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08003754 }
Eric Dumazet349ce992014-10-23 12:58:58 -07003755 return tcp_md5sig_pool_populated;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08003756}
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08003757EXPORT_SYMBOL(tcp_alloc_md5sig_pool);
3758
Eric Dumazet35790c02010-05-16 00:34:04 -07003759
3760/**
3761 * tcp_get_md5sig_pool - get md5sig_pool for this user
3762 *
3763 * We use percpu structure, so if we succeed, we exit with preemption
3764 * and BH disabled, to make sure another thread or softirq handling
3765 * wont try to get same context.
3766 */
3767struct tcp_md5sig_pool *tcp_get_md5sig_pool(void)
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08003768{
Eric Dumazet35790c02010-05-16 00:34:04 -07003769 local_bh_disable();
Eric Dumazet35790c02010-05-16 00:34:04 -07003770
Eric Dumazet349ce992014-10-23 12:58:58 -07003771 if (tcp_md5sig_pool_populated) {
3772 /* coupled with smp_wmb() in __tcp_alloc_md5sig_pool() */
3773 smp_rmb();
3774 return this_cpu_ptr(&tcp_md5sig_pool);
3775 }
Eric Dumazet35790c02010-05-16 00:34:04 -07003776 local_bh_enable();
3777 return NULL;
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08003778}
Eric Dumazet35790c02010-05-16 00:34:04 -07003779EXPORT_SYMBOL(tcp_get_md5sig_pool);
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08003780
Adam Langley49a72df2008-07-19 00:01:42 -07003781int tcp_md5_hash_skb_data(struct tcp_md5sig_pool *hp,
Eric Dumazetcf533ea2011-10-21 05:22:42 -04003782 const struct sk_buff *skb, unsigned int header_len)
Adam Langley49a72df2008-07-19 00:01:42 -07003783{
3784 struct scatterlist sg;
3785 const struct tcphdr *tp = tcp_hdr(skb);
Herbert Xucf80e0e2016-01-24 21:20:23 +08003786 struct ahash_request *req = hp->md5_req;
Eric Dumazet95c96172012-04-15 05:58:06 +00003787 unsigned int i;
3788 const unsigned int head_data_len = skb_headlen(skb) > header_len ?
3789 skb_headlen(skb) - header_len : 0;
Adam Langley49a72df2008-07-19 00:01:42 -07003790 const struct skb_shared_info *shi = skb_shinfo(skb);
Eric Dumazetd7fd1b572010-05-17 20:40:51 +00003791 struct sk_buff *frag_iter;
Adam Langley49a72df2008-07-19 00:01:42 -07003792
3793 sg_init_table(&sg, 1);
3794
3795 sg_set_buf(&sg, ((u8 *) tp) + header_len, head_data_len);
Herbert Xucf80e0e2016-01-24 21:20:23 +08003796 ahash_request_set_crypt(req, &sg, NULL, head_data_len);
3797 if (crypto_ahash_update(req))
Adam Langley49a72df2008-07-19 00:01:42 -07003798 return 1;
3799
3800 for (i = 0; i < shi->nr_frags; ++i) {
Matthew Wilcox (Oracle)d8e18a52019-07-22 20:08:26 -07003801 const skb_frag_t *f = &shi->frags[i];
Jonathan Lemonb54c9d52019-07-30 07:40:33 -07003802 unsigned int offset = skb_frag_off(f);
Eric Dumazet54d27fc2013-05-13 21:25:52 +00003803 struct page *page = skb_frag_page(f) + (offset >> PAGE_SHIFT);
3804
3805 sg_set_page(&sg, page, skb_frag_size(f),
3806 offset_in_page(offset));
Herbert Xucf80e0e2016-01-24 21:20:23 +08003807 ahash_request_set_crypt(req, &sg, NULL, skb_frag_size(f));
3808 if (crypto_ahash_update(req))
Adam Langley49a72df2008-07-19 00:01:42 -07003809 return 1;
3810 }
3811
Eric Dumazetd7fd1b572010-05-17 20:40:51 +00003812 skb_walk_frags(skb, frag_iter)
3813 if (tcp_md5_hash_skb_data(hp, frag_iter, 0))
3814 return 1;
3815
Adam Langley49a72df2008-07-19 00:01:42 -07003816 return 0;
3817}
Adam Langley49a72df2008-07-19 00:01:42 -07003818EXPORT_SYMBOL(tcp_md5_hash_skb_data);
3819
Eric Dumazetcf533ea2011-10-21 05:22:42 -04003820int tcp_md5_hash_key(struct tcp_md5sig_pool *hp, const struct tcp_md5sig_key *key)
Adam Langley49a72df2008-07-19 00:01:42 -07003821{
3822 struct scatterlist sg;
3823
3824 sg_init_one(&sg, key->key, key->keylen);
Herbert Xucf80e0e2016-01-24 21:20:23 +08003825 ahash_request_set_crypt(hp->md5_req, &sg, NULL, key->keylen);
3826 return crypto_ahash_update(hp->md5_req);
Adam Langley49a72df2008-07-19 00:01:42 -07003827}
Adam Langley49a72df2008-07-19 00:01:42 -07003828EXPORT_SYMBOL(tcp_md5_hash_key);
3829
YOSHIFUJI Hideakicfb6eeb2006-11-14 19:07:45 -08003830#endif
3831
Andi Kleen4ac02ba2007-04-20 17:11:46 -07003832void tcp_done(struct sock *sk)
3833{
Jerry Chu83368862012-08-31 12:29:12 +00003834 struct request_sock *req = tcp_sk(sk)->fastopen_rsk;
3835
Jianjun Kong5a5f3a82008-11-03 00:24:34 -08003836 if (sk->sk_state == TCP_SYN_SENT || sk->sk_state == TCP_SYN_RECV)
Eric Dumazetc10d9312016-04-29 14:16:47 -07003837 TCP_INC_STATS(sock_net(sk), TCP_MIB_ATTEMPTFAILS);
Andi Kleen4ac02ba2007-04-20 17:11:46 -07003838
3839 tcp_set_state(sk, TCP_CLOSE);
3840 tcp_clear_xmit_timers(sk);
Ian Morris00db4122015-04-03 09:17:27 +01003841 if (req)
Jerry Chu83368862012-08-31 12:29:12 +00003842 reqsk_fastopen_remove(sk, req, false);
Andi Kleen4ac02ba2007-04-20 17:11:46 -07003843
3844 sk->sk_shutdown = SHUTDOWN_MASK;
3845
3846 if (!sock_flag(sk, SOCK_DEAD))
3847 sk->sk_state_change(sk);
3848 else
3849 inet_csk_destroy_sock(sk);
3850}
3851EXPORT_SYMBOL_GPL(tcp_done);
3852
Lorenzo Colittic1e64e22015-12-16 12:30:05 +09003853int tcp_abort(struct sock *sk, int err)
3854{
3855 if (!sk_fullsock(sk)) {
Eric Dumazet07f6f4a2015-12-17 16:14:11 -08003856 if (sk->sk_state == TCP_NEW_SYN_RECV) {
3857 struct request_sock *req = inet_reqsk(sk);
3858
3859 local_bh_disable();
Lorenzo Colittiacc2cf42018-07-07 16:31:40 +09003860 inet_csk_reqsk_queue_drop(req->rsk_listener, req);
Eric Dumazet07f6f4a2015-12-17 16:14:11 -08003861 local_bh_enable();
3862 return 0;
3863 }
Lorenzo Colittic1e64e22015-12-16 12:30:05 +09003864 return -EOPNOTSUPP;
3865 }
3866
3867 /* Don't race with userspace socket closes such as tcp_close. */
3868 lock_sock(sk);
3869
Lorenzo Colitti2010b932015-12-22 00:03:44 +09003870 if (sk->sk_state == TCP_LISTEN) {
3871 tcp_set_state(sk, TCP_CLOSE);
3872 inet_csk_listen_stop(sk);
3873 }
3874
Lorenzo Colittic1e64e22015-12-16 12:30:05 +09003875 /* Don't race with BH socket closes such as inet_csk_listen_stop. */
3876 local_bh_disable();
3877 bh_lock_sock(sk);
3878
3879 if (!sock_flag(sk, SOCK_DEAD)) {
3880 sk->sk_err = err;
3881 /* This barrier is coupled with smp_rmb() in tcp_poll() */
3882 smp_wmb();
3883 sk->sk_error_report(sk);
3884 if (tcp_need_reset(sk->sk_state))
3885 tcp_send_active_reset(sk, GFP_ATOMIC);
3886 tcp_done(sk);
3887 }
3888
3889 bh_unlock_sock(sk);
3890 local_bh_enable();
Soheil Hassas Yeganehe05836a2018-03-06 17:15:12 -05003891 tcp_write_queue_purge(sk);
Lorenzo Colittic1e64e22015-12-16 12:30:05 +09003892 release_sock(sk);
Lorenzo Colittic1e64e22015-12-16 12:30:05 +09003893 return 0;
3894}
3895EXPORT_SYMBOL_GPL(tcp_abort);
3896
Stephen Hemminger5f8ef482005-06-23 20:37:36 -07003897extern struct tcp_congestion_ops tcp_reno;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003898
3899static __initdata unsigned long thash_entries;
3900static int __init set_thash_entries(char *str)
3901{
Eldad Zack413c27d2012-05-19 14:13:18 +00003902 ssize_t ret;
3903
Linus Torvalds1da177e2005-04-16 15:20:36 -07003904 if (!str)
3905 return 0;
Eldad Zack413c27d2012-05-19 14:13:18 +00003906
3907 ret = kstrtoul(str, 0, &thash_entries);
3908 if (ret)
3909 return 0;
3910
Linus Torvalds1da177e2005-04-16 15:20:36 -07003911 return 1;
3912}
3913__setup("thash_entries=", set_thash_entries);
3914
Fabian Frederick47d7a88c2014-10-01 18:27:50 +02003915static void __init tcp_init_mem(void)
Glauber Costa4acb4192012-01-30 01:20:17 +00003916{
Eric Dumazetb66e91c2015-05-15 12:39:30 -07003917 unsigned long limit = nr_free_buffer_pages() / 16;
3918
Glauber Costa4acb4192012-01-30 01:20:17 +00003919 limit = max(limit, 128UL);
Eric Dumazetb66e91c2015-05-15 12:39:30 -07003920 sysctl_tcp_mem[0] = limit / 4 * 3; /* 4.68 % */
3921 sysctl_tcp_mem[1] = limit; /* 6.25 % */
3922 sysctl_tcp_mem[2] = sysctl_tcp_mem[0] * 2; /* 9.37 % */
Glauber Costa4acb4192012-01-30 01:20:17 +00003923}
3924
Linus Torvalds1da177e2005-04-16 15:20:36 -07003925void __init tcp_init(void)
3926{
Eric Dumazetb49960a2012-05-02 02:28:41 +00003927 int max_rshare, max_wshare, cnt;
Eric Dumazetb2d3ea42016-09-19 23:39:12 -04003928 unsigned long limit;
Dimitri Sivanich074b8512012-02-08 12:39:07 -08003929 unsigned int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003930
Eric Dumazet3b4929f2019-05-17 17:17:22 -07003931 BUILD_BUG_ON(TCP_MIN_SND_MSS <= MAX_TCP_OPTION_SPACE);
Eric Dumazetb2d3ea42016-09-19 23:39:12 -04003932 BUILD_BUG_ON(sizeof(struct tcp_skb_cb) >
3933 FIELD_SIZEOF(struct sk_buff, cb));
Linus Torvalds1da177e2005-04-16 15:20:36 -07003934
Tejun Heo908c7f12014-09-08 09:51:29 +09003935 percpu_counter_init(&tcp_sockets_allocated, 0, GFP_KERNEL);
3936 percpu_counter_init(&tcp_orphan_count, 0, GFP_KERNEL);
Haishuang Yan1946e672016-12-28 17:52:32 +08003937 inet_hashinfo_init(&tcp_hashinfo);
Martin KaFai Lau27da6d32017-12-01 12:52:32 -08003938 inet_hashinfo2_init(&tcp_hashinfo, "tcp_listen_portaddr_hash",
3939 thash_entries, 21, /* one slot per 2 MB*/
3940 0, 64 * 1024);
Arnaldo Carvalho de Melo6e04e022005-08-09 20:07:35 -07003941 tcp_hashinfo.bind_bucket_cachep =
3942 kmem_cache_create("tcp_bind_bucket",
3943 sizeof(struct inet_bind_bucket), 0,
Paul Mundt20c2df82007-07-20 10:11:58 +09003944 SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003945
Linus Torvalds1da177e2005-04-16 15:20:36 -07003946 /* Size and allocate the main established and bind bucket
3947 * hash tables.
3948 *
3949 * The methodology is similar to that of the buffer cache.
3950 */
Arnaldo Carvalho de Melo6e04e022005-08-09 20:07:35 -07003951 tcp_hashinfo.ehash =
Linus Torvalds1da177e2005-04-16 15:20:36 -07003952 alloc_large_system_hash("TCP established",
Arnaldo Carvalho de Melo0f7ff922005-08-09 19:59:44 -07003953 sizeof(struct inet_ehash_bucket),
Linus Torvalds1da177e2005-04-16 15:20:36 -07003954 thash_entries,
Eric Dumazetfd90b292012-11-30 10:08:52 +00003955 17, /* one slot per 128 KB of memory */
John Heffner9e950ef2006-11-06 23:10:51 -08003956 0,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003957 NULL,
Eric Dumazetf373b532009-10-09 00:16:19 +00003958 &tcp_hashinfo.ehash_mask,
Tim Bird31fe62b2012-05-23 13:33:35 +00003959 0,
Jean Delvare0ccfe612007-10-30 00:59:25 -07003960 thash_entries ? 0 : 512 * 1024);
Eric Dumazet05dbc7b2013-10-03 00:22:02 -07003961 for (i = 0; i <= tcp_hashinfo.ehash_mask; i++)
Eric Dumazet3ab5aee2008-11-16 19:40:17 -08003962 INIT_HLIST_NULLS_HEAD(&tcp_hashinfo.ehash[i].chain, i);
Eric Dumazet05dbc7b2013-10-03 00:22:02 -07003963
Eric Dumazet230140c2007-11-07 02:40:20 -08003964 if (inet_ehash_locks_alloc(&tcp_hashinfo))
3965 panic("TCP: failed to alloc ehash_locks");
Arnaldo Carvalho de Melo6e04e022005-08-09 20:07:35 -07003966 tcp_hashinfo.bhash =
Linus Torvalds1da177e2005-04-16 15:20:36 -07003967 alloc_large_system_hash("TCP bind",
Arnaldo Carvalho de Melo0f7ff922005-08-09 19:59:44 -07003968 sizeof(struct inet_bind_hashbucket),
Eric Dumazetf373b532009-10-09 00:16:19 +00003969 tcp_hashinfo.ehash_mask + 1,
Eric Dumazetfd90b292012-11-30 10:08:52 +00003970 17, /* one slot per 128 KB of memory */
John Heffner9e950ef2006-11-06 23:10:51 -08003971 0,
Arnaldo Carvalho de Melo6e04e022005-08-09 20:07:35 -07003972 &tcp_hashinfo.bhash_size,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003973 NULL,
Tim Bird31fe62b2012-05-23 13:33:35 +00003974 0,
Linus Torvalds1da177e2005-04-16 15:20:36 -07003975 64 * 1024);
Dimitri Sivanich074b8512012-02-08 12:39:07 -08003976 tcp_hashinfo.bhash_size = 1U << tcp_hashinfo.bhash_size;
Arnaldo Carvalho de Melo6e04e022005-08-09 20:07:35 -07003977 for (i = 0; i < tcp_hashinfo.bhash_size; i++) {
3978 spin_lock_init(&tcp_hashinfo.bhash[i].lock);
3979 INIT_HLIST_HEAD(&tcp_hashinfo.bhash[i].chain);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003980 }
3981
Eric Dumazetc5ed63d2010-08-25 23:02:17 -07003982
3983 cnt = tcp_hashinfo.ehash_mask + 1;
Eric Dumazetc5ed63d2010-08-25 23:02:17 -07003984 sysctl_tcp_max_orphans = cnt / 2;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003985
Eric W. Biedermana4fe34b2013-10-19 16:25:36 -07003986 tcp_init_mem();
Jason Wangc43b8742012-02-02 00:07:00 +00003987 /* Set per-socket limits to no more than 1/128 the pressure threshold */
Eric Dumazet5fb84b12012-04-10 00:56:42 +00003988 limit = nr_free_buffer_pages() << (PAGE_SHIFT - 7);
Eric Dumazetb49960a2012-05-02 02:28:41 +00003989 max_wshare = min(4UL*1024*1024, limit);
3990 max_rshare = min(6UL*1024*1024, limit);
John Heffner7b4f4b52006-03-25 01:34:07 -08003991
Eric Dumazet356d1832017-11-07 00:29:28 -08003992 init_net.ipv4.sysctl_tcp_wmem[0] = SK_MEM_QUANTUM;
3993 init_net.ipv4.sysctl_tcp_wmem[1] = 16*1024;
3994 init_net.ipv4.sysctl_tcp_wmem[2] = max(64*1024, max_wshare);
John Heffner7b4f4b52006-03-25 01:34:07 -08003995
Eric Dumazet356d1832017-11-07 00:29:28 -08003996 init_net.ipv4.sysctl_tcp_rmem[0] = SK_MEM_QUANTUM;
Yuchung Chenga3375312018-09-27 11:21:19 -07003997 init_net.ipv4.sysctl_tcp_rmem[1] = 131072;
3998 init_net.ipv4.sysctl_tcp_rmem[2] = max(131072, max_rshare);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003999
Joe Perchesafd465032012-03-12 07:03:32 +00004000 pr_info("Hash tables configured (established %u bind %u)\n",
Joe Perches058bd4d2012-03-11 18:36:11 +00004001 tcp_hashinfo.ehash_mask + 1, tcp_hashinfo.bhash_size);
Stephen Hemminger317a76f2005-06-23 12:19:55 -07004002
Haishuang Yan1946e672016-12-28 17:52:32 +08004003 tcp_v4_init();
David S. Miller51c5d0c2012-07-10 00:49:14 -07004004 tcp_metrics_init();
Florian Westphal55d86942014-09-26 22:37:32 +02004005 BUG_ON(tcp_register_congestion_control(&tcp_reno) != 0);
Eric Dumazet46d3cea2012-07-11 05:50:31 +00004006 tcp_tasklet_init();
Linus Torvalds1da177e2005-04-16 15:20:36 -07004007}