xref: /linux/fs/lockd/svc.c (revision 070a542f08acb7e8cf197287f5c44658c715d2d1)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * linux/fs/lockd/svc.c
4  *
5  * This is the central lockd service.
6  *
7  * FIXME: Separate the lockd NFS server functionality from the lockd NFS
8  * 	  client functionality. Oh why didn't Sun create two separate
9  *	  services in the first place?
10  *
11  * Authors:	Olaf Kirch (okir@monad.swb.de)
12  *
13  * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
14  */
15 
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/sysctl.h>
19 #include <linux/moduleparam.h>
20 
21 #include <linux/sched/signal.h>
22 #include <linux/errno.h>
23 #include <linux/in.h>
24 #include <linux/uio.h>
25 #include <linux/smp.h>
26 #include <linux/mutex.h>
27 #include <linux/freezer.h>
28 #include <linux/inetdevice.h>
29 
30 #include <linux/sunrpc/types.h>
31 #include <linux/sunrpc/stats.h>
32 #include <linux/sunrpc/clnt.h>
33 #include <linux/sunrpc/svc.h>
34 #include <linux/sunrpc/svcsock.h>
35 #include <linux/sunrpc/svc_xprt.h>
36 #include <net/ip.h>
37 #include <net/addrconf.h>
38 #include <net/ipv6.h>
39 #include <linux/lockd/lockd.h>
40 #include <linux/nfs.h>
41 
42 #include "netns.h"
43 #include "procfs.h"
44 #include "netlink.h"
45 
46 #define NLMDBG_FACILITY		NLMDBG_SVC
47 #define LOCKD_BUFSIZE		(1024 + NLMSVC_XDRSIZE)
48 
49 static struct svc_program	nlmsvc_program;
50 
51 const struct nlmsvc_binding	*nlmsvc_ops;
52 EXPORT_SYMBOL_GPL(nlmsvc_ops);
53 
54 static DEFINE_MUTEX(nlmsvc_mutex);
55 static unsigned int		nlmsvc_users;
56 static struct svc_serv		*nlmsvc_serv;
57 
nlmsvc_request_retry(struct timer_list * tl)58 static void nlmsvc_request_retry(struct timer_list *tl)
59 {
60 	svc_wake_up(nlmsvc_serv);
61 }
62 DEFINE_TIMER(nlmsvc_retry, nlmsvc_request_retry);
63 
64 unsigned int lockd_net_id;
65 
66 /*
67  * These can be set at insmod time (useful for NFS as root filesystem),
68  * and also changed through the sysctl interface.  -- Jamie Lokier, Aug 2003
69  */
70 static unsigned long		nlm_grace_period;
71 unsigned long			nlm_timeout = LOCKD_DFLT_TIMEO;
72 static int			nlm_udpport, nlm_tcpport;
73 
74 /*
75  * Constants needed for the sysctl interface.
76  */
77 static const unsigned long	nlm_grace_period_min = 0;
78 static const unsigned long	nlm_grace_period_max = 240;
79 static const unsigned long	nlm_timeout_min = 3;
80 static const unsigned long	nlm_timeout_max = 20;
81 
82 #ifdef CONFIG_SYSCTL
83 static const int		nlm_port_min = 0, nlm_port_max = 65535;
84 static struct ctl_table_header * nlm_sysctl_table;
85 #endif
86 
get_lockd_grace_period(struct net * net)87 static unsigned long get_lockd_grace_period(struct net *net)
88 {
89 	struct lockd_net *ln = net_generic(net, lockd_net_id);
90 
91 	/* Return the net-ns specific grace period, if there is one */
92 	if (ln->gracetime)
93 		return ln->gracetime * HZ;
94 
95 	/* Note: nlm_timeout should always be nonzero */
96 	if (nlm_grace_period)
97 		return roundup(nlm_grace_period, nlm_timeout) * HZ;
98 	else
99 		return nlm_timeout * 5 * HZ;
100 }
101 
grace_ender(struct work_struct * grace)102 static void grace_ender(struct work_struct *grace)
103 {
104 	struct delayed_work *dwork = to_delayed_work(grace);
105 	struct lockd_net *ln = container_of(dwork, struct lockd_net,
106 					    grace_period_end);
107 
108 	locks_end_grace(&ln->lockd_manager);
109 }
110 
set_grace_period(struct net * net)111 static void set_grace_period(struct net *net)
112 {
113 	unsigned long grace_period = get_lockd_grace_period(net);
114 	struct lockd_net *ln = net_generic(net, lockd_net_id);
115 
116 	locks_start_grace(net, &ln->lockd_manager);
117 	cancel_delayed_work_sync(&ln->grace_period_end);
118 	schedule_delayed_work(&ln->grace_period_end, grace_period);
119 }
120 
121 /*
122  * This is the lockd kernel thread
123  */
124 static int
lockd(void * vrqstp)125 lockd(void *vrqstp)
126 {
127 	struct svc_rqst *rqstp = vrqstp;
128 	struct net *net = &init_net;
129 	struct lockd_net *ln = net_generic(net, lockd_net_id);
130 
131 	svc_thread_init_status(rqstp, 0);
132 
133 	/* try_to_freeze() is called from svc_recv() */
134 	set_freezable();
135 
136 	dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
137 
138 	/*
139 	 * The main request loop. We don't terminate until the last
140 	 * NFS mount or NFS daemon has gone away.
141 	 */
142 	while (!svc_thread_should_stop(rqstp)) {
143 		nlmsvc_retry_blocked(rqstp);
144 		svc_recv(rqstp);
145 	}
146 	if (nlmsvc_ops)
147 		nlmsvc_invalidate_all();
148 	nlm_shutdown_hosts();
149 	cancel_delayed_work_sync(&ln->grace_period_end);
150 	locks_end_grace(&ln->lockd_manager);
151 
152 	dprintk("lockd_down: service stopped\n");
153 
154 	svc_exit_thread(rqstp);
155 	return 0;
156 }
157 
create_lockd_listener(struct svc_serv * serv,const char * name,struct net * net,const int family,const unsigned short port,const struct cred * cred)158 static int create_lockd_listener(struct svc_serv *serv, const char *name,
159 				 struct net *net, const int family,
160 				 const unsigned short port,
161 				 const struct cred *cred)
162 {
163 	struct svc_xprt *xprt;
164 
165 	xprt = svc_find_xprt(serv, name, net, family, 0);
166 	if (xprt == NULL)
167 		return svc_xprt_create(serv, name, net, family, port,
168 				       SVC_SOCK_DEFAULTS, cred);
169 	svc_xprt_put(xprt);
170 	return 0;
171 }
172 
create_lockd_family(struct svc_serv * serv,struct net * net,const int family,const struct cred * cred)173 static int create_lockd_family(struct svc_serv *serv, struct net *net,
174 			       const int family, const struct cred *cred)
175 {
176 	struct lockd_net *ln = net_generic(net, lockd_net_id);
177 	int err;
178 
179 	err = create_lockd_listener(serv, "udp", net, family,
180 				    ln->udp_port ? ln->udp_port : nlm_udpport, cred);
181 	if (err < 0)
182 		return err;
183 
184 	return create_lockd_listener(serv, "tcp", net, family,
185 				     ln->tcp_port ? ln->tcp_port : nlm_tcpport, cred);
186 }
187 
188 /*
189  * Ensure there are active UDP and TCP listeners for lockd.
190  *
191  * Even if we have only TCP NFS mounts and/or TCP NFSDs, some
192  * local services (such as rpc.statd) still require UDP, and
193  * some NFS servers do not yet support NLM over TCP.
194  *
195  * Returns zero if all listeners are available; otherwise a
196  * negative errno value is returned.
197  */
make_socks(struct svc_serv * serv,struct net * net,const struct cred * cred)198 static int make_socks(struct svc_serv *serv, struct net *net,
199 		const struct cred *cred)
200 {
201 	static int warned;
202 	int err;
203 
204 	err = create_lockd_family(serv, net, PF_INET, cred);
205 	if (err < 0)
206 		goto out_err;
207 
208 	err = create_lockd_family(serv, net, PF_INET6, cred);
209 	if (err < 0 && err != -EAFNOSUPPORT)
210 		goto out_err;
211 
212 	warned = 0;
213 	return 0;
214 
215 out_err:
216 	if (warned++ == 0)
217 		printk(KERN_WARNING
218 			"lockd_up: makesock failed, error=%d\n", err);
219 	svc_xprt_destroy_all(serv, net, true);
220 	return err;
221 }
222 
lockd_up_net(struct svc_serv * serv,struct net * net,const struct cred * cred)223 static int lockd_up_net(struct svc_serv *serv, struct net *net,
224 		const struct cred *cred)
225 {
226 	struct lockd_net *ln = net_generic(net, lockd_net_id);
227 	int error;
228 
229 	if (ln->nlmsvc_users++)
230 		return 0;
231 
232 	error = svc_bind(serv, net);
233 	if (error)
234 		goto err_bind;
235 
236 	error = make_socks(serv, net, cred);
237 	if (error < 0)
238 		goto err_bind;
239 	set_grace_period(net);
240 	dprintk("%s: per-net data created; net=%x\n", __func__, net->ns.inum);
241 	return 0;
242 
243 err_bind:
244 	ln->nlmsvc_users--;
245 	return error;
246 }
247 
lockd_down_net(struct svc_serv * serv,struct net * net)248 static void lockd_down_net(struct svc_serv *serv, struct net *net)
249 {
250 	struct lockd_net *ln = net_generic(net, lockd_net_id);
251 
252 	if (ln->nlmsvc_users) {
253 		if (--ln->nlmsvc_users == 0) {
254 			nlm_shutdown_hosts_net(net);
255 			cancel_delayed_work_sync(&ln->grace_period_end);
256 			locks_end_grace(&ln->lockd_manager);
257 			svc_xprt_destroy_all(serv, net, true);
258 		}
259 	} else {
260 		pr_err("%s: no users! net=%x\n",
261 			__func__, net->ns.inum);
262 		BUG();
263 	}
264 }
265 
lockd_inetaddr_event(struct notifier_block * this,unsigned long event,void * ptr)266 static int lockd_inetaddr_event(struct notifier_block *this,
267 	unsigned long event, void *ptr)
268 {
269 	struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
270 	struct sockaddr_in sin;
271 
272 	if (event != NETDEV_DOWN)
273 		goto out;
274 
275 	if (nlmsvc_serv) {
276 		dprintk("lockd_inetaddr_event: removed %pI4\n",
277 			&ifa->ifa_local);
278 		sin.sin_family = AF_INET;
279 		sin.sin_addr.s_addr = ifa->ifa_local;
280 		svc_age_temp_xprts_now(nlmsvc_serv, (struct sockaddr *)&sin);
281 	}
282 
283 out:
284 	return NOTIFY_DONE;
285 }
286 
287 static struct notifier_block lockd_inetaddr_notifier = {
288 	.notifier_call = lockd_inetaddr_event,
289 };
290 
291 #if IS_ENABLED(CONFIG_IPV6)
lockd_inet6addr_event(struct notifier_block * this,unsigned long event,void * ptr)292 static int lockd_inet6addr_event(struct notifier_block *this,
293 	unsigned long event, void *ptr)
294 {
295 	struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
296 	struct sockaddr_in6 sin6;
297 
298 	if (event != NETDEV_DOWN)
299 		goto out;
300 
301 	if (nlmsvc_serv) {
302 		dprintk("lockd_inet6addr_event: removed %pI6\n", &ifa->addr);
303 		sin6.sin6_family = AF_INET6;
304 		sin6.sin6_addr = ifa->addr;
305 		if (ipv6_addr_type(&sin6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
306 			sin6.sin6_scope_id = ifa->idev->dev->ifindex;
307 		svc_age_temp_xprts_now(nlmsvc_serv, (struct sockaddr *)&sin6);
308 	}
309 
310 out:
311 	return NOTIFY_DONE;
312 }
313 
314 static struct notifier_block lockd_inet6addr_notifier = {
315 	.notifier_call = lockd_inet6addr_event,
316 };
317 #endif
318 
lockd_get(void)319 static int lockd_get(void)
320 {
321 	struct svc_serv *serv;
322 	int error;
323 
324 	if (nlmsvc_serv) {
325 		nlmsvc_users++;
326 		return 0;
327 	}
328 
329 	/*
330 	 * Sanity check: if there's no pid,
331 	 * we should be the first user ...
332 	 */
333 	if (nlmsvc_users)
334 		printk(KERN_WARNING
335 			"lockd_up: no pid, %d users??\n", nlmsvc_users);
336 
337 	serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, lockd);
338 	if (!serv) {
339 		printk(KERN_WARNING "lockd_up: create service failed\n");
340 		return -ENOMEM;
341 	}
342 
343 	error = svc_set_num_threads(serv, NULL, 1);
344 	if (error < 0) {
345 		svc_destroy(&serv);
346 		return error;
347 	}
348 
349 	nlmsvc_serv = serv;
350 	register_inetaddr_notifier(&lockd_inetaddr_notifier);
351 #if IS_ENABLED(CONFIG_IPV6)
352 	register_inet6addr_notifier(&lockd_inet6addr_notifier);
353 #endif
354 	dprintk("lockd_up: service created\n");
355 	nlmsvc_users++;
356 	return 0;
357 }
358 
lockd_put(void)359 static void lockd_put(void)
360 {
361 	if (WARN(nlmsvc_users <= 0, "lockd_down: no users!\n"))
362 		return;
363 	if (--nlmsvc_users)
364 		return;
365 
366 	unregister_inetaddr_notifier(&lockd_inetaddr_notifier);
367 #if IS_ENABLED(CONFIG_IPV6)
368 	unregister_inet6addr_notifier(&lockd_inet6addr_notifier);
369 #endif
370 
371 	svc_set_num_threads(nlmsvc_serv, NULL, 0);
372 	timer_delete_sync(&nlmsvc_retry);
373 	svc_destroy(&nlmsvc_serv);
374 	dprintk("lockd_down: service destroyed\n");
375 }
376 
377 /*
378  * Bring up the lockd process if it's not already up.
379  */
lockd_up(struct net * net,const struct cred * cred)380 int lockd_up(struct net *net, const struct cred *cred)
381 {
382 	int error;
383 
384 	mutex_lock(&nlmsvc_mutex);
385 
386 	error = lockd_get();
387 	if (error)
388 		goto err;
389 
390 	error = lockd_up_net(nlmsvc_serv, net, cred);
391 	if (error < 0) {
392 		lockd_put();
393 		goto err;
394 	}
395 
396 err:
397 	mutex_unlock(&nlmsvc_mutex);
398 	return error;
399 }
400 EXPORT_SYMBOL_GPL(lockd_up);
401 
402 /*
403  * Decrement the user count and bring down lockd if we're the last.
404  */
405 void
lockd_down(struct net * net)406 lockd_down(struct net *net)
407 {
408 	mutex_lock(&nlmsvc_mutex);
409 	lockd_down_net(nlmsvc_serv, net);
410 	lockd_put();
411 	mutex_unlock(&nlmsvc_mutex);
412 }
413 EXPORT_SYMBOL_GPL(lockd_down);
414 
415 #ifdef CONFIG_SYSCTL
416 
417 /*
418  * Sysctl parameters (same as module parameters, different interface).
419  */
420 
421 static const struct ctl_table nlm_sysctls[] = {
422 	{
423 		.procname	= "nlm_grace_period",
424 		.data		= &nlm_grace_period,
425 		.maxlen		= sizeof(unsigned long),
426 		.mode		= 0644,
427 		.proc_handler	= proc_doulongvec_minmax,
428 		.extra1		= (unsigned long *) &nlm_grace_period_min,
429 		.extra2		= (unsigned long *) &nlm_grace_period_max,
430 	},
431 	{
432 		.procname	= "nlm_timeout",
433 		.data		= &nlm_timeout,
434 		.maxlen		= sizeof(unsigned long),
435 		.mode		= 0644,
436 		.proc_handler	= proc_doulongvec_minmax,
437 		.extra1		= (unsigned long *) &nlm_timeout_min,
438 		.extra2		= (unsigned long *) &nlm_timeout_max,
439 	},
440 	{
441 		.procname	= "nlm_udpport",
442 		.data		= &nlm_udpport,
443 		.maxlen		= sizeof(int),
444 		.mode		= 0644,
445 		.proc_handler	= proc_dointvec_minmax,
446 		.extra1		= (int *) &nlm_port_min,
447 		.extra2		= (int *) &nlm_port_max,
448 	},
449 	{
450 		.procname	= "nlm_tcpport",
451 		.data		= &nlm_tcpport,
452 		.maxlen		= sizeof(int),
453 		.mode		= 0644,
454 		.proc_handler	= proc_dointvec_minmax,
455 		.extra1		= (int *) &nlm_port_min,
456 		.extra2		= (int *) &nlm_port_max,
457 	},
458 	{
459 		.procname	= "nsm_use_hostnames",
460 		.data		= &nsm_use_hostnames,
461 		.maxlen		= sizeof(bool),
462 		.mode		= 0644,
463 		.proc_handler	= proc_dobool,
464 	},
465 	{
466 		.procname	= "nsm_local_state",
467 		.data		= &nsm_local_state,
468 		.maxlen		= sizeof(nsm_local_state),
469 		.mode		= 0644,
470 		.proc_handler	= proc_douintvec,
471 		.extra1		= SYSCTL_ZERO,
472 	},
473 };
474 
475 #endif	/* CONFIG_SYSCTL */
476 
477 /*
478  * Module (and sysfs) parameters.
479  */
480 
481 #define param_set_min_max(name, type, which_strtol, min, max)		\
482 static int param_set_##name(const char *val, const struct kernel_param *kp) \
483 {									\
484 	char *endp;							\
485 	__typeof__(type) num = which_strtol(val, &endp, 0);		\
486 	if (endp == val || *endp || num < (min) || num > (max))		\
487 		return -EINVAL;						\
488 	*((type *) kp->arg) = num;					\
489 	return 0;							\
490 }
491 
is_callback(u32 proc)492 static inline int is_callback(u32 proc)
493 {
494 	return proc == NLMPROC_GRANTED
495 		|| proc == NLMPROC_GRANTED_MSG
496 		|| proc == NLMPROC_TEST_RES
497 		|| proc == NLMPROC_LOCK_RES
498 		|| proc == NLMPROC_CANCEL_RES
499 		|| proc == NLMPROC_UNLOCK_RES
500 		|| proc == NLMPROC_NSM_NOTIFY;
501 }
502 
503 
lockd_authenticate(struct svc_rqst * rqstp)504 static enum svc_auth_status lockd_authenticate(struct svc_rqst *rqstp)
505 {
506 	rqstp->rq_client = NULL;
507 	switch (rqstp->rq_authop->flavour) {
508 		case RPC_AUTH_NULL:
509 		case RPC_AUTH_UNIX:
510 			rqstp->rq_auth_stat = rpc_auth_ok;
511 			if (rqstp->rq_proc == 0)
512 				return SVC_OK;
513 			if (is_callback(rqstp->rq_proc)) {
514 				/* Leave it to individual procedures to
515 				 * call nlmsvc_lookup_host(rqstp)
516 				 */
517 				return SVC_OK;
518 			}
519 			return svc_set_client(rqstp);
520 	}
521 	rqstp->rq_auth_stat = rpc_autherr_badcred;
522 	return SVC_DENIED;
523 }
524 
525 
526 param_set_min_max(port, int, simple_strtol, 0, 65535)
527 param_set_min_max(grace_period, unsigned long, simple_strtoul,
528 		  nlm_grace_period_min, nlm_grace_period_max)
529 param_set_min_max(timeout, unsigned long, simple_strtoul,
530 		  nlm_timeout_min, nlm_timeout_max)
531 
532 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
533 MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
534 MODULE_LICENSE("GPL");
535 
536 module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
537 		  &nlm_grace_period, 0644);
538 module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
539 		  &nlm_timeout, 0644);
540 module_param_call(nlm_udpport, param_set_port, param_get_int,
541 		  &nlm_udpport, 0644);
542 module_param_call(nlm_tcpport, param_set_port, param_get_int,
543 		  &nlm_tcpport, 0644);
544 module_param(nsm_use_hostnames, bool, 0644);
545 
lockd_init_net(struct net * net)546 static int lockd_init_net(struct net *net)
547 {
548 	struct lockd_net *ln = net_generic(net, lockd_net_id);
549 
550 	INIT_DELAYED_WORK(&ln->grace_period_end, grace_ender);
551 	INIT_LIST_HEAD(&ln->lockd_manager.list);
552 	ln->lockd_manager.block_opens = false;
553 	INIT_LIST_HEAD(&ln->nsm_handles);
554 	return 0;
555 }
556 
lockd_exit_net(struct net * net)557 static void lockd_exit_net(struct net *net)
558 {
559 	struct lockd_net *ln = net_generic(net, lockd_net_id);
560 
561 	WARN_ONCE(!list_empty(&ln->lockd_manager.list),
562 		  "net %x %s: lockd_manager.list is not empty\n",
563 		  net->ns.inum, __func__);
564 	WARN_ONCE(!list_empty(&ln->nsm_handles),
565 		  "net %x %s: nsm_handles list is not empty\n",
566 		  net->ns.inum, __func__);
567 	WARN_ONCE(delayed_work_pending(&ln->grace_period_end),
568 		  "net %x %s: grace_period_end was not cancelled\n",
569 		  net->ns.inum, __func__);
570 }
571 
572 static struct pernet_operations lockd_net_ops = {
573 	.init = lockd_init_net,
574 	.exit = lockd_exit_net,
575 	.id = &lockd_net_id,
576 	.size = sizeof(struct lockd_net),
577 };
578 
579 
580 /*
581  * Initialising and terminating the module.
582  */
583 
init_nlm(void)584 static int __init init_nlm(void)
585 {
586 	int err;
587 
588 #ifdef CONFIG_SYSCTL
589 	err = -ENOMEM;
590 	nlm_sysctl_table = register_sysctl("fs/nfs", nlm_sysctls);
591 	if (nlm_sysctl_table == NULL)
592 		goto err_sysctl;
593 #endif
594 	err = register_pernet_subsys(&lockd_net_ops);
595 	if (err)
596 		goto err_pernet;
597 
598 	err = genl_register_family(&lockd_nl_family);
599 	if (err)
600 		goto err_netlink;
601 
602 	err = lockd_create_procfs();
603 	if (err)
604 		goto err_procfs;
605 
606 	return 0;
607 
608 err_procfs:
609 	genl_unregister_family(&lockd_nl_family);
610 err_netlink:
611 	unregister_pernet_subsys(&lockd_net_ops);
612 err_pernet:
613 #ifdef CONFIG_SYSCTL
614 	unregister_sysctl_table(nlm_sysctl_table);
615 err_sysctl:
616 #endif
617 	return err;
618 }
619 
exit_nlm(void)620 static void __exit exit_nlm(void)
621 {
622 	/* FIXME: delete all NLM clients */
623 	nlm_shutdown_hosts();
624 	genl_unregister_family(&lockd_nl_family);
625 	lockd_remove_procfs();
626 	unregister_pernet_subsys(&lockd_net_ops);
627 #ifdef CONFIG_SYSCTL
628 	unregister_sysctl_table(nlm_sysctl_table);
629 #endif
630 }
631 
632 module_init(init_nlm);
633 module_exit(exit_nlm);
634 
635 /**
636  * nlmsvc_dispatch - Process an NLM Request
637  * @rqstp: incoming request
638  *
639  * Return values:
640  *  %0: Processing complete; do not send a Reply
641  *  %1: Processing complete; send Reply in rqstp->rq_res
642  */
nlmsvc_dispatch(struct svc_rqst * rqstp)643 static int nlmsvc_dispatch(struct svc_rqst *rqstp)
644 {
645 	const struct svc_procedure *procp = rqstp->rq_procinfo;
646 	__be32 *statp = rqstp->rq_accept_statp;
647 
648 	if (!procp->pc_decode(rqstp, &rqstp->rq_arg_stream))
649 		goto out_decode_err;
650 
651 	*statp = procp->pc_func(rqstp);
652 	if (*statp == rpc_drop_reply)
653 		return 0;
654 	if (*statp != rpc_success)
655 		return 1;
656 
657 	if (!procp->pc_encode(rqstp, &rqstp->rq_res_stream))
658 		goto out_encode_err;
659 
660 	return 1;
661 
662 out_decode_err:
663 	*statp = rpc_garbage_args;
664 	return 1;
665 
666 out_encode_err:
667 	*statp = rpc_system_err;
668 	return 1;
669 }
670 
671 /*
672  * Define NLM program and procedures
673  */
674 static DEFINE_PER_CPU_ALIGNED(unsigned long, nlmsvc_version1_count[17]);
675 static const struct svc_version	nlmsvc_version1 = {
676 	.vs_vers	= 1,
677 	.vs_nproc	= 17,
678 	.vs_proc	= nlmsvc_procedures,
679 	.vs_count	= nlmsvc_version1_count,
680 	.vs_dispatch	= nlmsvc_dispatch,
681 	.vs_xdrsize	= NLMSVC_XDRSIZE,
682 };
683 
684 static DEFINE_PER_CPU_ALIGNED(unsigned long,
685 			      nlmsvc_version3_count[ARRAY_SIZE(nlmsvc_procedures)]);
686 static const struct svc_version	nlmsvc_version3 = {
687 	.vs_vers	= 3,
688 	.vs_nproc	= ARRAY_SIZE(nlmsvc_procedures),
689 	.vs_proc	= nlmsvc_procedures,
690 	.vs_count	= nlmsvc_version3_count,
691 	.vs_dispatch	= nlmsvc_dispatch,
692 	.vs_xdrsize	= NLMSVC_XDRSIZE,
693 };
694 
695 #ifdef CONFIG_LOCKD_V4
696 static DEFINE_PER_CPU_ALIGNED(unsigned long,
697 			      nlmsvc_version4_count[ARRAY_SIZE(nlmsvc_procedures4)]);
698 static const struct svc_version	nlmsvc_version4 = {
699 	.vs_vers	= 4,
700 	.vs_nproc	= ARRAY_SIZE(nlmsvc_procedures4),
701 	.vs_proc	= nlmsvc_procedures4,
702 	.vs_count	= nlmsvc_version4_count,
703 	.vs_dispatch	= nlmsvc_dispatch,
704 	.vs_xdrsize	= NLMSVC_XDRSIZE,
705 };
706 #endif
707 
708 static const struct svc_version *nlmsvc_version[] = {
709 	[1] = &nlmsvc_version1,
710 	[3] = &nlmsvc_version3,
711 #ifdef CONFIG_LOCKD_V4
712 	[4] = &nlmsvc_version4,
713 #endif
714 };
715 
716 #define NLM_NRVERS	ARRAY_SIZE(nlmsvc_version)
717 static struct svc_program	nlmsvc_program = {
718 	.pg_prog		= NLM_PROGRAM,		/* program number */
719 	.pg_nvers		= NLM_NRVERS,		/* number of entries in nlmsvc_version */
720 	.pg_vers		= nlmsvc_version,	/* version table */
721 	.pg_name		= "lockd",		/* service name */
722 	.pg_class		= "nfsd",		/* share authentication with nfsd */
723 	.pg_authenticate	= &lockd_authenticate,	/* export authentication */
724 	.pg_init_request	= svc_generic_init_request,
725 	.pg_rpcbind_set		= svc_generic_rpcbind_set,
726 };
727 
728 /**
729  * lockd_nl_server_set_doit - set the lockd server parameters via netlink
730  * @skb: reply buffer
731  * @info: netlink metadata and command arguments
732  *
733  * This updates the per-net values. When updating the values in the init_net
734  * namespace, also update the "legacy" global values.
735  *
736  * Return 0 on success or a negative errno.
737  */
lockd_nl_server_set_doit(struct sk_buff * skb,struct genl_info * info)738 int lockd_nl_server_set_doit(struct sk_buff *skb, struct genl_info *info)
739 {
740 	struct net *net = genl_info_net(info);
741 	struct lockd_net *ln = net_generic(net, lockd_net_id);
742 	const struct nlattr *attr;
743 
744 	if (GENL_REQ_ATTR_CHECK(info, LOCKD_A_SERVER_GRACETIME))
745 		return -EINVAL;
746 
747 	if (info->attrs[LOCKD_A_SERVER_GRACETIME] ||
748 	    info->attrs[LOCKD_A_SERVER_TCP_PORT] ||
749 	    info->attrs[LOCKD_A_SERVER_UDP_PORT]) {
750 		attr = info->attrs[LOCKD_A_SERVER_GRACETIME];
751 		if (attr) {
752 			u32 gracetime = nla_get_u32(attr);
753 
754 			if (gracetime > nlm_grace_period_max)
755 				return -EINVAL;
756 
757 			ln->gracetime = gracetime;
758 
759 			if (net == &init_net)
760 				nlm_grace_period = gracetime;
761 		}
762 
763 		attr = info->attrs[LOCKD_A_SERVER_TCP_PORT];
764 		if (attr) {
765 			ln->tcp_port = nla_get_u16(attr);
766 			if (net == &init_net)
767 				nlm_tcpport = ln->tcp_port;
768 		}
769 
770 		attr = info->attrs[LOCKD_A_SERVER_UDP_PORT];
771 		if (attr) {
772 			ln->udp_port = nla_get_u16(attr);
773 			if (net == &init_net)
774 				nlm_udpport = ln->udp_port;
775 		}
776 	}
777 	return 0;
778 }
779 
780 /**
781  * lockd_nl_server_get_doit - get lockd server parameters via netlink
782  * @skb: reply buffer
783  * @info: netlink metadata and command arguments
784  *
785  * Return 0 on success or a negative errno.
786  */
lockd_nl_server_get_doit(struct sk_buff * skb,struct genl_info * info)787 int lockd_nl_server_get_doit(struct sk_buff *skb, struct genl_info *info)
788 {
789 	struct net *net = genl_info_net(info);
790 	struct lockd_net *ln = net_generic(net, lockd_net_id);
791 	void *hdr;
792 	int err;
793 
794 	skb = genlmsg_new(GENLMSG_DEFAULT_SIZE, GFP_KERNEL);
795 	if (!skb)
796 		return -ENOMEM;
797 
798 	hdr = genlmsg_iput(skb, info);
799 	if (!hdr) {
800 		err = -EMSGSIZE;
801 		goto err_free_msg;
802 	}
803 
804 	err = nla_put_u32(skb, LOCKD_A_SERVER_GRACETIME, ln->gracetime) ||
805 	      nla_put_u16(skb, LOCKD_A_SERVER_TCP_PORT, ln->tcp_port) ||
806 	      nla_put_u16(skb, LOCKD_A_SERVER_UDP_PORT, ln->udp_port);
807 	if (err)
808 		goto err_free_msg;
809 
810 	genlmsg_end(skb, hdr);
811 
812 	return genlmsg_reply(skb, info);
813 err_free_msg:
814 	nlmsg_free(skb);
815 
816 	return err;
817 }
818