1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * File: socket.c
4 *
5 * Phonet sockets
6 *
7 * Copyright (C) 2008 Nokia Corporation.
8 *
9 * Authors: Sakari Ailus <sakari.ailus@nokia.com>
10 * Rémi Denis-Courmont
11 */
12
13 #include <linux/gfp.h>
14 #include <linux/kernel.h>
15 #include <linux/net.h>
16 #include <linux/poll.h>
17 #include <linux/sched/signal.h>
18
19 #include <net/sock.h>
20 #include <net/tcp_states.h>
21
22 #include <linux/phonet.h>
23 #include <linux/export.h>
24 #include <net/phonet/phonet.h>
25 #include <net/phonet/pep.h>
26 #include <net/phonet/pn_dev.h>
27
pn_socket_release(struct socket * sock)28 static int pn_socket_release(struct socket *sock)
29 {
30 struct sock *sk = sock->sk;
31
32 if (sk) {
33 sock->sk = NULL;
34 sk->sk_prot->close(sk, 0);
35 }
36 return 0;
37 }
38
39 #define PN_HASHSIZE 16
40 #define PN_HASHMASK (PN_HASHSIZE-1)
41
42
43 static struct {
44 struct hlist_head hlist[PN_HASHSIZE];
45 struct mutex lock;
46 } pnsocks;
47
pn_sock_init(void)48 void __init pn_sock_init(void)
49 {
50 unsigned int i;
51
52 for (i = 0; i < PN_HASHSIZE; i++)
53 INIT_HLIST_HEAD(pnsocks.hlist + i);
54 mutex_init(&pnsocks.lock);
55 }
56
pn_hash_list(u16 obj)57 static struct hlist_head *pn_hash_list(u16 obj)
58 {
59 return pnsocks.hlist + (obj & PN_HASHMASK);
60 }
61
62 /*
63 * Find address based on socket address, match only certain fields.
64 * Also grab sock if it was found. Remember to sock_put it later.
65 */
pn_find_sock_by_sa(struct net * net,const struct sockaddr_pn * spn)66 struct sock *pn_find_sock_by_sa(struct net *net, const struct sockaddr_pn *spn)
67 {
68 struct sock *sknode;
69 struct sock *rval = NULL;
70 u16 obj = pn_sockaddr_get_object(spn);
71 u8 res = spn->spn_resource;
72 struct hlist_head *hlist = pn_hash_list(obj);
73
74 rcu_read_lock();
75 sk_for_each_rcu(sknode, hlist) {
76 struct pn_sock *pn = pn_sk(sknode);
77 BUG_ON(!pn->sobject); /* unbound socket */
78
79 if (!net_eq(sock_net(sknode), net))
80 continue;
81 if (pn_port(obj)) {
82 /* Look up socket by port */
83 if (pn_port(pn->sobject) != pn_port(obj))
84 continue;
85 } else {
86 /* If port is zero, look up by resource */
87 if (pn->resource != res)
88 continue;
89 }
90 if (pn_addr(pn->sobject) &&
91 pn_addr(pn->sobject) != pn_addr(obj))
92 continue;
93
94 rval = sknode;
95 sock_hold(sknode);
96 break;
97 }
98 rcu_read_unlock();
99
100 return rval;
101 }
102
103 /* Deliver a broadcast packet (only in bottom-half) */
pn_deliver_sock_broadcast(struct net * net,struct sk_buff * skb)104 void pn_deliver_sock_broadcast(struct net *net, struct sk_buff *skb)
105 {
106 struct hlist_head *hlist = pnsocks.hlist;
107 unsigned int h;
108
109 rcu_read_lock();
110 for (h = 0; h < PN_HASHSIZE; h++) {
111 struct sock *sknode;
112
113 sk_for_each(sknode, hlist) {
114 struct sk_buff *clone;
115
116 if (!net_eq(sock_net(sknode), net))
117 continue;
118 if (!sock_flag(sknode, SOCK_BROADCAST))
119 continue;
120
121 clone = skb_clone(skb, GFP_ATOMIC);
122 if (clone) {
123 sock_hold(sknode);
124 sk_receive_skb(sknode, clone, 0);
125 }
126 }
127 hlist++;
128 }
129 rcu_read_unlock();
130 }
131
pn_sock_hash(struct sock * sk)132 int pn_sock_hash(struct sock *sk)
133 {
134 struct hlist_head *hlist = pn_hash_list(pn_sk(sk)->sobject);
135
136 mutex_lock(&pnsocks.lock);
137 sk_add_node_rcu(sk, hlist);
138 mutex_unlock(&pnsocks.lock);
139
140 return 0;
141 }
142 EXPORT_SYMBOL(pn_sock_hash);
143
pn_sock_unhash(struct sock * sk)144 void pn_sock_unhash(struct sock *sk)
145 {
146 mutex_lock(&pnsocks.lock);
147 sk_del_node_init_rcu(sk);
148 mutex_unlock(&pnsocks.lock);
149 pn_sock_unbind_all_res(sk);
150 synchronize_rcu();
151 }
152 EXPORT_SYMBOL(pn_sock_unhash);
153
154 static DEFINE_MUTEX(port_mutex);
155
pn_socket_bind(struct socket * sock,struct sockaddr * addr,int len)156 static int pn_socket_bind(struct socket *sock, struct sockaddr *addr, int len)
157 {
158 struct sock *sk = sock->sk;
159 struct pn_sock *pn = pn_sk(sk);
160 struct sockaddr_pn *spn = (struct sockaddr_pn *)addr;
161 int err;
162 u16 handle;
163 u8 saddr;
164
165 if (sk->sk_prot->bind)
166 return sk->sk_prot->bind(sk, addr, len);
167
168 if (len < sizeof(struct sockaddr_pn))
169 return -EINVAL;
170 if (spn->spn_family != AF_PHONET)
171 return -EAFNOSUPPORT;
172
173 handle = pn_sockaddr_get_object((struct sockaddr_pn *)addr);
174 saddr = pn_addr(handle);
175 if (saddr && phonet_address_lookup(sock_net(sk), saddr))
176 return -EADDRNOTAVAIL;
177
178 lock_sock(sk);
179 if (sk->sk_state != TCP_CLOSE || pn_port(pn->sobject)) {
180 err = -EINVAL; /* attempt to rebind */
181 goto out;
182 }
183 WARN_ON(sk_hashed(sk));
184 mutex_lock(&port_mutex);
185 err = sk->sk_prot->get_port(sk, pn_port(handle));
186 if (err)
187 goto out_port;
188
189 /* get_port() sets the port, bind() sets the address if applicable */
190 pn->sobject = pn_object(saddr, pn_port(pn->sobject));
191 pn->resource = spn->spn_resource;
192
193 /* Enable RX on the socket */
194 err = sk->sk_prot->hash(sk);
195 out_port:
196 mutex_unlock(&port_mutex);
197 out:
198 release_sock(sk);
199 return err;
200 }
201
pn_socket_autobind(struct socket * sock)202 static int pn_socket_autobind(struct socket *sock)
203 {
204 struct sockaddr_pn sa;
205 int err;
206
207 memset(&sa, 0, sizeof(sa));
208 sa.spn_family = AF_PHONET;
209 err = pn_socket_bind(sock, (struct sockaddr *)&sa,
210 sizeof(struct sockaddr_pn));
211 if (err != -EINVAL)
212 return err;
213 BUG_ON(!pn_port(pn_sk(sock->sk)->sobject));
214 return 0; /* socket was already bound */
215 }
216
pn_socket_connect(struct socket * sock,struct sockaddr * addr,int len,int flags)217 static int pn_socket_connect(struct socket *sock, struct sockaddr *addr,
218 int len, int flags)
219 {
220 struct sock *sk = sock->sk;
221 struct pn_sock *pn = pn_sk(sk);
222 struct sockaddr_pn *spn = (struct sockaddr_pn *)addr;
223 struct task_struct *tsk = current;
224 long timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);
225 int err;
226
227 if (pn_socket_autobind(sock))
228 return -ENOBUFS;
229 if (len < sizeof(struct sockaddr_pn))
230 return -EINVAL;
231 if (spn->spn_family != AF_PHONET)
232 return -EAFNOSUPPORT;
233
234 lock_sock(sk);
235
236 switch (sock->state) {
237 case SS_UNCONNECTED:
238 if (sk->sk_state != TCP_CLOSE) {
239 err = -EISCONN;
240 goto out;
241 }
242 break;
243 case SS_CONNECTING:
244 err = -EALREADY;
245 goto out;
246 default:
247 err = -EISCONN;
248 goto out;
249 }
250
251 pn->dobject = pn_sockaddr_get_object(spn);
252 pn->resource = pn_sockaddr_get_resource(spn);
253 sock->state = SS_CONNECTING;
254
255 err = sk->sk_prot->connect(sk, addr, len);
256 if (err) {
257 sock->state = SS_UNCONNECTED;
258 pn->dobject = 0;
259 goto out;
260 }
261
262 while (sk->sk_state == TCP_SYN_SENT) {
263 DEFINE_WAIT(wait);
264
265 if (!timeo) {
266 err = -EINPROGRESS;
267 goto out;
268 }
269 if (signal_pending(tsk)) {
270 err = sock_intr_errno(timeo);
271 goto out;
272 }
273
274 prepare_to_wait_exclusive(sk_sleep(sk), &wait,
275 TASK_INTERRUPTIBLE);
276 release_sock(sk);
277 timeo = schedule_timeout(timeo);
278 lock_sock(sk);
279 finish_wait(sk_sleep(sk), &wait);
280 }
281
282 if ((1 << sk->sk_state) & (TCPF_SYN_RECV|TCPF_ESTABLISHED))
283 err = 0;
284 else if (sk->sk_state == TCP_CLOSE_WAIT)
285 err = -ECONNRESET;
286 else
287 err = -ECONNREFUSED;
288 sock->state = err ? SS_UNCONNECTED : SS_CONNECTED;
289 out:
290 release_sock(sk);
291 return err;
292 }
293
pn_socket_accept(struct socket * sock,struct socket * newsock,struct proto_accept_arg * arg)294 static int pn_socket_accept(struct socket *sock, struct socket *newsock,
295 struct proto_accept_arg *arg)
296 {
297 struct sock *sk = sock->sk;
298 struct sock *newsk;
299
300 if (unlikely(sk->sk_state != TCP_LISTEN))
301 return -EINVAL;
302
303 newsk = sk->sk_prot->accept(sk, arg);
304 if (!newsk)
305 return arg->err;
306
307 lock_sock(newsk);
308 sock_graft(newsk, newsock);
309 newsock->state = SS_CONNECTED;
310 release_sock(newsk);
311 return 0;
312 }
313
pn_socket_getname(struct socket * sock,struct sockaddr * addr,int peer)314 static int pn_socket_getname(struct socket *sock, struct sockaddr *addr,
315 int peer)
316 {
317 struct sock *sk = sock->sk;
318 struct pn_sock *pn = pn_sk(sk);
319
320 memset(addr, 0, sizeof(struct sockaddr_pn));
321 addr->sa_family = AF_PHONET;
322 if (!peer) /* Race with bind() here is userland's problem. */
323 pn_sockaddr_set_object((struct sockaddr_pn *)addr,
324 pn->sobject);
325
326 return sizeof(struct sockaddr_pn);
327 }
328
pn_socket_poll(struct file * file,struct socket * sock,poll_table * wait)329 static __poll_t pn_socket_poll(struct file *file, struct socket *sock,
330 poll_table *wait)
331 {
332 struct sock *sk = sock->sk;
333 struct pep_sock *pn = pep_sk(sk);
334 __poll_t mask = 0;
335
336 poll_wait(file, sk_sleep(sk), wait);
337
338 if (sk->sk_state == TCP_CLOSE)
339 return EPOLLERR;
340 if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
341 mask |= EPOLLIN | EPOLLRDNORM;
342 if (!skb_queue_empty_lockless(&pn->ctrlreq_queue))
343 mask |= EPOLLPRI;
344 if (!mask && sk->sk_state == TCP_CLOSE_WAIT)
345 return EPOLLHUP;
346
347 if (sk->sk_state == TCP_ESTABLISHED &&
348 refcount_read(&sk->sk_wmem_alloc) < sk->sk_sndbuf &&
349 atomic_read(&pn->tx_credits))
350 mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
351
352 return mask;
353 }
354
pn_socket_ioctl(struct socket * sock,unsigned int cmd,unsigned long arg)355 static int pn_socket_ioctl(struct socket *sock, unsigned int cmd,
356 unsigned long arg)
357 {
358 struct sock *sk = sock->sk;
359 struct pn_sock *pn = pn_sk(sk);
360
361 if (cmd == SIOCPNGETOBJECT) {
362 struct net_device *dev;
363 u16 handle;
364 u8 saddr;
365
366 if (get_user(handle, (__u16 __user *)arg))
367 return -EFAULT;
368
369 lock_sock(sk);
370 if (sk->sk_bound_dev_if)
371 dev = dev_get_by_index(sock_net(sk),
372 sk->sk_bound_dev_if);
373 else
374 dev = phonet_device_get(sock_net(sk));
375 if (dev && (dev->flags & IFF_UP))
376 saddr = phonet_address_get(dev, pn_addr(handle));
377 else
378 saddr = PN_NO_ADDR;
379 release_sock(sk);
380
381 dev_put(dev);
382 if (saddr == PN_NO_ADDR)
383 return -EHOSTUNREACH;
384
385 handle = pn_object(saddr, pn_port(pn->sobject));
386 return put_user(handle, (__u16 __user *)arg);
387 }
388
389 return sk_ioctl(sk, cmd, (void __user *)arg);
390 }
391
pn_socket_listen(struct socket * sock,int backlog)392 static int pn_socket_listen(struct socket *sock, int backlog)
393 {
394 struct sock *sk = sock->sk;
395 int err = 0;
396
397 if (pn_socket_autobind(sock))
398 return -ENOBUFS;
399
400 lock_sock(sk);
401 if (sock->state != SS_UNCONNECTED) {
402 err = -EINVAL;
403 goto out;
404 }
405
406 if (sk->sk_state != TCP_LISTEN) {
407 sk->sk_state = TCP_LISTEN;
408 sk->sk_ack_backlog = 0;
409 }
410 sk->sk_max_ack_backlog = backlog;
411 out:
412 release_sock(sk);
413 return err;
414 }
415
pn_socket_sendmsg(struct socket * sock,struct msghdr * m,size_t total_len)416 static int pn_socket_sendmsg(struct socket *sock, struct msghdr *m,
417 size_t total_len)
418 {
419 struct sock *sk = sock->sk;
420
421 if (pn_socket_autobind(sock))
422 return -EAGAIN;
423
424 return sk->sk_prot->sendmsg(sk, m, total_len);
425 }
426
427 const struct proto_ops phonet_dgram_ops = {
428 .family = AF_PHONET,
429 .owner = THIS_MODULE,
430 .release = pn_socket_release,
431 .bind = pn_socket_bind,
432 .connect = sock_no_connect,
433 .socketpair = sock_no_socketpair,
434 .accept = sock_no_accept,
435 .getname = pn_socket_getname,
436 .poll = datagram_poll,
437 .ioctl = pn_socket_ioctl,
438 .listen = sock_no_listen,
439 .shutdown = sock_no_shutdown,
440 .sendmsg = pn_socket_sendmsg,
441 .recvmsg = sock_common_recvmsg,
442 .mmap = sock_no_mmap,
443 };
444
445 const struct proto_ops phonet_stream_ops = {
446 .family = AF_PHONET,
447 .owner = THIS_MODULE,
448 .release = pn_socket_release,
449 .bind = pn_socket_bind,
450 .connect = pn_socket_connect,
451 .socketpair = sock_no_socketpair,
452 .accept = pn_socket_accept,
453 .getname = pn_socket_getname,
454 .poll = pn_socket_poll,
455 .ioctl = pn_socket_ioctl,
456 .listen = pn_socket_listen,
457 .shutdown = sock_no_shutdown,
458 .setsockopt = sock_common_setsockopt,
459 .getsockopt = sock_common_getsockopt,
460 .sendmsg = pn_socket_sendmsg,
461 .recvmsg = sock_common_recvmsg,
462 .mmap = sock_no_mmap,
463 };
464 EXPORT_SYMBOL(phonet_stream_ops);
465
466 /* allocate port for a socket */
pn_sock_get_port(struct sock * sk,unsigned short sport)467 int pn_sock_get_port(struct sock *sk, unsigned short sport)
468 {
469 static int port_cur;
470 struct net *net = sock_net(sk);
471 struct pn_sock *pn = pn_sk(sk);
472 struct sockaddr_pn try_sa;
473 struct sock *tmpsk;
474
475 memset(&try_sa, 0, sizeof(struct sockaddr_pn));
476 try_sa.spn_family = AF_PHONET;
477 WARN_ON(!mutex_is_locked(&port_mutex));
478 if (!sport) {
479 /* search free port */
480 int port, pmin, pmax;
481
482 phonet_get_local_port_range(&pmin, &pmax);
483 for (port = pmin; port <= pmax; port++) {
484 port_cur++;
485 if (port_cur < pmin || port_cur > pmax)
486 port_cur = pmin;
487
488 pn_sockaddr_set_port(&try_sa, port_cur);
489 tmpsk = pn_find_sock_by_sa(net, &try_sa);
490 if (tmpsk == NULL) {
491 sport = port_cur;
492 goto found;
493 } else
494 sock_put(tmpsk);
495 }
496 } else {
497 /* try to find specific port */
498 pn_sockaddr_set_port(&try_sa, sport);
499 tmpsk = pn_find_sock_by_sa(net, &try_sa);
500 if (tmpsk == NULL)
501 /* No sock there! We can use that port... */
502 goto found;
503 else
504 sock_put(tmpsk);
505 }
506 /* the port must be in use already */
507 return -EADDRINUSE;
508
509 found:
510 pn->sobject = pn_object(pn_addr(pn->sobject), sport);
511 return 0;
512 }
513 EXPORT_SYMBOL(pn_sock_get_port);
514
515 #ifdef CONFIG_PROC_FS
pn_sock_get_idx(struct seq_file * seq,loff_t pos)516 static struct sock *pn_sock_get_idx(struct seq_file *seq, loff_t pos)
517 {
518 struct net *net = seq_file_net(seq);
519 struct hlist_head *hlist = pnsocks.hlist;
520 struct sock *sknode;
521 unsigned int h;
522
523 for (h = 0; h < PN_HASHSIZE; h++) {
524 sk_for_each_rcu(sknode, hlist) {
525 if (!net_eq(net, sock_net(sknode)))
526 continue;
527 if (!pos)
528 return sknode;
529 pos--;
530 }
531 hlist++;
532 }
533 return NULL;
534 }
535
pn_sock_get_next(struct seq_file * seq,struct sock * sk)536 static struct sock *pn_sock_get_next(struct seq_file *seq, struct sock *sk)
537 {
538 struct net *net = seq_file_net(seq);
539
540 do
541 sk = sk_next(sk);
542 while (sk && !net_eq(net, sock_net(sk)));
543
544 return sk;
545 }
546
pn_sock_seq_start(struct seq_file * seq,loff_t * pos)547 static void *pn_sock_seq_start(struct seq_file *seq, loff_t *pos)
548 __acquires(rcu)
549 {
550 rcu_read_lock();
551 return *pos ? pn_sock_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
552 }
553
pn_sock_seq_next(struct seq_file * seq,void * v,loff_t * pos)554 static void *pn_sock_seq_next(struct seq_file *seq, void *v, loff_t *pos)
555 {
556 struct sock *sk;
557
558 if (v == SEQ_START_TOKEN)
559 sk = pn_sock_get_idx(seq, 0);
560 else
561 sk = pn_sock_get_next(seq, v);
562 (*pos)++;
563 return sk;
564 }
565
pn_sock_seq_stop(struct seq_file * seq,void * v)566 static void pn_sock_seq_stop(struct seq_file *seq, void *v)
567 __releases(rcu)
568 {
569 rcu_read_unlock();
570 }
571
pn_sock_seq_show(struct seq_file * seq,void * v)572 static int pn_sock_seq_show(struct seq_file *seq, void *v)
573 {
574 seq_setwidth(seq, 127);
575 if (v == SEQ_START_TOKEN)
576 seq_puts(seq, "pt loc rem rs st tx_queue rx_queue "
577 " uid inode ref pointer drops");
578 else {
579 struct sock *sk = v;
580 struct pn_sock *pn = pn_sk(sk);
581
582 seq_printf(seq, "%2d %04X:%04X:%02X %02X %08X:%08X %5d %lu "
583 "%d %pK %u",
584 sk->sk_protocol, pn->sobject, pn->dobject,
585 pn->resource, sk->sk_state,
586 sk_wmem_alloc_get(sk), sk_rmem_alloc_get(sk),
587 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)),
588 sock_i_ino(sk),
589 refcount_read(&sk->sk_refcnt), sk,
590 atomic_read(&sk->sk_drops));
591 }
592 seq_pad(seq, '\n');
593 return 0;
594 }
595
596 const struct seq_operations pn_sock_seq_ops = {
597 .start = pn_sock_seq_start,
598 .next = pn_sock_seq_next,
599 .stop = pn_sock_seq_stop,
600 .show = pn_sock_seq_show,
601 };
602 #endif
603
604 static struct {
605 struct sock *sk[256];
606 } pnres;
607
608 /*
609 * Find and hold socket based on resource.
610 */
pn_find_sock_by_res(struct net * net,u8 res)611 struct sock *pn_find_sock_by_res(struct net *net, u8 res)
612 {
613 struct sock *sk;
614
615 if (!net_eq(net, &init_net))
616 return NULL;
617
618 rcu_read_lock();
619 sk = rcu_dereference(pnres.sk[res]);
620 if (sk)
621 sock_hold(sk);
622 rcu_read_unlock();
623 return sk;
624 }
625
626 static DEFINE_MUTEX(resource_mutex);
627
pn_sock_bind_res(struct sock * sk,u8 res)628 int pn_sock_bind_res(struct sock *sk, u8 res)
629 {
630 int ret = -EADDRINUSE;
631
632 if (!net_eq(sock_net(sk), &init_net))
633 return -ENOIOCTLCMD;
634 if (!capable(CAP_SYS_ADMIN))
635 return -EPERM;
636 if (pn_socket_autobind(sk->sk_socket))
637 return -EAGAIN;
638
639 mutex_lock(&resource_mutex);
640 if (pnres.sk[res] == NULL) {
641 sock_hold(sk);
642 rcu_assign_pointer(pnres.sk[res], sk);
643 ret = 0;
644 }
645 mutex_unlock(&resource_mutex);
646 return ret;
647 }
648
pn_sock_unbind_res(struct sock * sk,u8 res)649 int pn_sock_unbind_res(struct sock *sk, u8 res)
650 {
651 int ret = -ENOENT;
652
653 if (!capable(CAP_SYS_ADMIN))
654 return -EPERM;
655
656 mutex_lock(&resource_mutex);
657 if (pnres.sk[res] == sk) {
658 RCU_INIT_POINTER(pnres.sk[res], NULL);
659 ret = 0;
660 }
661 mutex_unlock(&resource_mutex);
662
663 if (ret == 0) {
664 synchronize_rcu();
665 sock_put(sk);
666 }
667 return ret;
668 }
669
pn_sock_unbind_all_res(struct sock * sk)670 void pn_sock_unbind_all_res(struct sock *sk)
671 {
672 unsigned int res, match = 0;
673
674 mutex_lock(&resource_mutex);
675 for (res = 0; res < 256; res++) {
676 if (pnres.sk[res] == sk) {
677 RCU_INIT_POINTER(pnres.sk[res], NULL);
678 match++;
679 }
680 }
681 mutex_unlock(&resource_mutex);
682
683 while (match > 0) {
684 __sock_put(sk);
685 match--;
686 }
687 /* Caller is responsible for RCU sync before final sock_put() */
688 }
689
690 #ifdef CONFIG_PROC_FS
pn_res_get_idx(struct seq_file * seq,loff_t pos)691 static struct sock **pn_res_get_idx(struct seq_file *seq, loff_t pos)
692 {
693 struct net *net = seq_file_net(seq);
694 unsigned int i;
695
696 if (!net_eq(net, &init_net))
697 return NULL;
698
699 for (i = 0; i < 256; i++) {
700 if (pnres.sk[i] == NULL)
701 continue;
702 if (!pos)
703 return pnres.sk + i;
704 pos--;
705 }
706 return NULL;
707 }
708
pn_res_get_next(struct seq_file * seq,struct sock ** sk)709 static struct sock **pn_res_get_next(struct seq_file *seq, struct sock **sk)
710 {
711 struct net *net = seq_file_net(seq);
712 unsigned int i;
713
714 BUG_ON(!net_eq(net, &init_net));
715
716 for (i = (sk - pnres.sk) + 1; i < 256; i++)
717 if (pnres.sk[i])
718 return pnres.sk + i;
719 return NULL;
720 }
721
pn_res_seq_start(struct seq_file * seq,loff_t * pos)722 static void *pn_res_seq_start(struct seq_file *seq, loff_t *pos)
723 __acquires(resource_mutex)
724 {
725 mutex_lock(&resource_mutex);
726 return *pos ? pn_res_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
727 }
728
pn_res_seq_next(struct seq_file * seq,void * v,loff_t * pos)729 static void *pn_res_seq_next(struct seq_file *seq, void *v, loff_t *pos)
730 {
731 struct sock **sk;
732
733 if (v == SEQ_START_TOKEN)
734 sk = pn_res_get_idx(seq, 0);
735 else
736 sk = pn_res_get_next(seq, v);
737 (*pos)++;
738 return sk;
739 }
740
pn_res_seq_stop(struct seq_file * seq,void * v)741 static void pn_res_seq_stop(struct seq_file *seq, void *v)
742 __releases(resource_mutex)
743 {
744 mutex_unlock(&resource_mutex);
745 }
746
pn_res_seq_show(struct seq_file * seq,void * v)747 static int pn_res_seq_show(struct seq_file *seq, void *v)
748 {
749 seq_setwidth(seq, 63);
750 if (v == SEQ_START_TOKEN)
751 seq_puts(seq, "rs uid inode");
752 else {
753 struct sock **psk = v;
754 struct sock *sk = *psk;
755
756 seq_printf(seq, "%02X %5u %lu",
757 (int) (psk - pnres.sk),
758 from_kuid_munged(seq_user_ns(seq), sock_i_uid(sk)),
759 sock_i_ino(sk));
760 }
761 seq_pad(seq, '\n');
762 return 0;
763 }
764
765 const struct seq_operations pn_res_seq_ops = {
766 .start = pn_res_seq_start,
767 .next = pn_res_seq_next,
768 .stop = pn_res_seq_stop,
769 .show = pn_res_seq_show,
770 };
771 #endif
772