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1// SPDX-License-Identifier: GPL-2.0-or-later2/* /proc interface for AFS3 *4 * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.5 * Written by David Howells (dhowells@redhat.com)6 */7 8#include <linux/slab.h>9#include <linux/module.h>10#include <linux/proc_fs.h>11#include <linux/seq_file.h>12#include <linux/sched.h>13#include <linux/uaccess.h>14#include "internal.h"15 16struct afs_vl_seq_net_private {17	struct seq_net_private		seq;	/* Must be first */18	struct afs_vlserver_list	*vllist;19};20 21static inline struct afs_net *afs_seq2net(struct seq_file *m)22{23	return afs_net(seq_file_net(m));24}25 26static inline struct afs_net *afs_seq2net_single(struct seq_file *m)27{28	return afs_net(seq_file_single_net(m));29}30 31/*32 * Display the list of cells known to the namespace.33 */34static int afs_proc_cells_show(struct seq_file *m, void *v)35{36	struct afs_vlserver_list *vllist;37	struct afs_cell *cell;38 39	if (v == SEQ_START_TOKEN) {40		/* display header on line 1 */41		seq_puts(m, "USE ACT    TTL SV ST NAME\n");42		return 0;43	}44 45	cell = list_entry(v, struct afs_cell, proc_link);46	vllist = rcu_dereference(cell->vl_servers);47 48	/* display one cell per line on subsequent lines */49	seq_printf(m, "%3u %3u %6lld %2u %2u %s\n",50		   refcount_read(&cell->ref),51		   atomic_read(&cell->active),52		   cell->dns_expiry - ktime_get_real_seconds(),53		   vllist ? vllist->nr_servers : 0,54		   cell->state,55		   cell->name);56	return 0;57}58 59static void *afs_proc_cells_start(struct seq_file *m, loff_t *_pos)60	__acquires(rcu)61{62	rcu_read_lock();63	return seq_hlist_start_head_rcu(&afs_seq2net(m)->proc_cells, *_pos);64}65 66static void *afs_proc_cells_next(struct seq_file *m, void *v, loff_t *pos)67{68	return seq_hlist_next_rcu(v, &afs_seq2net(m)->proc_cells, pos);69}70 71static void afs_proc_cells_stop(struct seq_file *m, void *v)72	__releases(rcu)73{74	rcu_read_unlock();75}76 77static const struct seq_operations afs_proc_cells_ops = {78	.start	= afs_proc_cells_start,79	.next	= afs_proc_cells_next,80	.stop	= afs_proc_cells_stop,81	.show	= afs_proc_cells_show,82};83 84/*85 * handle writes to /proc/fs/afs/cells86 * - to add cells: echo "add <cellname> <IP>[:<IP>][:<IP>]"87 */88static int afs_proc_cells_write(struct file *file, char *buf, size_t size)89{90	struct seq_file *m = file->private_data;91	struct afs_net *net = afs_seq2net(m);92	char *name, *args;93	int ret;94 95	/* trim to first NL */96	name = memchr(buf, '\n', size);97	if (name)98		*name = 0;99 100	/* split into command, name and argslist */101	name = strchr(buf, ' ');102	if (!name)103		goto inval;104	do {105		*name++ = 0;106	} while(*name == ' ');107	if (!*name)108		goto inval;109 110	args = strchr(name, ' ');111	if (args) {112		do {113			*args++ = 0;114		} while(*args == ' ');115		if (!*args)116			goto inval;117	}118 119	/* determine command to perform */120	_debug("cmd=%s name=%s args=%s", buf, name, args);121 122	if (strcmp(buf, "add") == 0) {123		struct afs_cell *cell;124 125		cell = afs_lookup_cell(net, name, strlen(name), args, true);126		if (IS_ERR(cell)) {127			ret = PTR_ERR(cell);128			goto done;129		}130 131		if (test_and_set_bit(AFS_CELL_FL_NO_GC, &cell->flags))132			afs_unuse_cell(net, cell, afs_cell_trace_unuse_no_pin);133	} else {134		goto inval;135	}136 137	ret = 0;138 139done:140	_leave(" = %d", ret);141	return ret;142 143inval:144	ret = -EINVAL;145	printk("kAFS: Invalid Command on /proc/fs/afs/cells file\n");146	goto done;147}148 149/*150 * Display the list of addr_prefs known to the namespace.151 */152static int afs_proc_addr_prefs_show(struct seq_file *m, void *v)153{154	struct afs_addr_preference_list *preflist;155	struct afs_addr_preference *pref;156	struct afs_net *net = afs_seq2net_single(m);157	union {158		struct sockaddr_in sin;159		struct sockaddr_in6 sin6;160	} addr;161	unsigned int i;162	char buf[44]; /* Maximum ipv6 + max subnet is 43 */163 164	rcu_read_lock();165	preflist = rcu_dereference(net->address_prefs);166 167	if (!preflist) {168		seq_puts(m, "NO PREFS\n");169		goto out;170	}171 172	seq_printf(m, "PROT SUBNET                                      PRIOR (v=%u n=%u/%u/%u)\n",173		   preflist->version, preflist->ipv6_off, preflist->nr, preflist->max_prefs);174 175	memset(&addr, 0, sizeof(addr));176 177	for (i = 0; i < preflist->nr; i++) {178		pref = &preflist->prefs[i];179 180		addr.sin.sin_family = pref->family;181		if (pref->family == AF_INET) {182			memcpy(&addr.sin.sin_addr, &pref->ipv4_addr,183			       sizeof(addr.sin.sin_addr));184			snprintf(buf, sizeof(buf), "%pISc/%u", &addr.sin, pref->subnet_mask);185			seq_printf(m, "UDP  %-43.43s %5u\n", buf, pref->prio);186		} else {187			memcpy(&addr.sin6.sin6_addr, &pref->ipv6_addr,188			       sizeof(addr.sin6.sin6_addr));189			snprintf(buf, sizeof(buf), "%pISc/%u", &addr.sin6, pref->subnet_mask);190			seq_printf(m, "UDP  %-43.43s %5u\n", buf, pref->prio);191		}192	}193 194out:195	rcu_read_unlock();196	return 0;197}198 199/*200 * Display the name of the current workstation cell.201 */202static int afs_proc_rootcell_show(struct seq_file *m, void *v)203{204	struct afs_cell *cell;205	struct afs_net *net;206 207	net = afs_seq2net_single(m);208	down_read(&net->cells_lock);209	cell = net->ws_cell;210	if (cell)211		seq_printf(m, "%s\n", cell->name);212	up_read(&net->cells_lock);213	return 0;214}215 216/*217 * Set the current workstation cell and optionally supply its list of volume218 * location servers.219 *220 *	echo "cell.name:192.168.231.14" >/proc/fs/afs/rootcell221 */222static int afs_proc_rootcell_write(struct file *file, char *buf, size_t size)223{224	struct seq_file *m = file->private_data;225	struct afs_net *net = afs_seq2net_single(m);226	char *s;227	int ret;228 229	ret = -EINVAL;230	if (buf[0] == '.')231		goto out;232	if (memchr(buf, '/', size))233		goto out;234 235	/* trim to first NL */236	s = memchr(buf, '\n', size);237	if (s)238		*s = 0;239 240	/* determine command to perform */241	_debug("rootcell=%s", buf);242 243	ret = afs_cell_init(net, buf);244 245out:246	_leave(" = %d", ret);247	return ret;248}249 250static const char afs_vol_types[3][3] = {251	[AFSVL_RWVOL]	= "RW",252	[AFSVL_ROVOL]	= "RO",253	[AFSVL_BACKVOL]	= "BK",254};255 256/*257 * Display the list of volumes known to a cell.258 */259static int afs_proc_cell_volumes_show(struct seq_file *m, void *v)260{261	struct afs_volume *vol = hlist_entry(v, struct afs_volume, proc_link);262 263	/* Display header on line 1 */264	if (v == SEQ_START_TOKEN) {265		seq_puts(m, "USE VID      TY NAME\n");266		return 0;267	}268 269	seq_printf(m, "%3d %08llx %s %s\n",270		   refcount_read(&vol->ref), vol->vid,271		   afs_vol_types[vol->type],272		   vol->name);273 274	return 0;275}276 277static void *afs_proc_cell_volumes_start(struct seq_file *m, loff_t *_pos)278	__acquires(cell->proc_lock)279{280	struct afs_cell *cell = pde_data(file_inode(m->file));281 282	rcu_read_lock();283	return seq_hlist_start_head_rcu(&cell->proc_volumes, *_pos);284}285 286static void *afs_proc_cell_volumes_next(struct seq_file *m, void *v,287					loff_t *_pos)288{289	struct afs_cell *cell = pde_data(file_inode(m->file));290 291	return seq_hlist_next_rcu(v, &cell->proc_volumes, _pos);292}293 294static void afs_proc_cell_volumes_stop(struct seq_file *m, void *v)295	__releases(cell->proc_lock)296{297	rcu_read_unlock();298}299 300static const struct seq_operations afs_proc_cell_volumes_ops = {301	.start	= afs_proc_cell_volumes_start,302	.next	= afs_proc_cell_volumes_next,303	.stop	= afs_proc_cell_volumes_stop,304	.show	= afs_proc_cell_volumes_show,305};306 307static const char *const dns_record_sources[NR__dns_record_source + 1] = {308	[DNS_RECORD_UNAVAILABLE]	= "unav",309	[DNS_RECORD_FROM_CONFIG]	= "cfg",310	[DNS_RECORD_FROM_DNS_A]		= "A",311	[DNS_RECORD_FROM_DNS_AFSDB]	= "AFSDB",312	[DNS_RECORD_FROM_DNS_SRV]	= "SRV",313	[DNS_RECORD_FROM_NSS]		= "nss",314	[NR__dns_record_source]		= "[weird]"315};316 317static const char *const dns_lookup_statuses[NR__dns_lookup_status + 1] = {318	[DNS_LOOKUP_NOT_DONE]		= "no-lookup",319	[DNS_LOOKUP_GOOD]		= "good",320	[DNS_LOOKUP_GOOD_WITH_BAD]	= "good/bad",321	[DNS_LOOKUP_BAD]		= "bad",322	[DNS_LOOKUP_GOT_NOT_FOUND]	= "not-found",323	[DNS_LOOKUP_GOT_LOCAL_FAILURE]	= "local-failure",324	[DNS_LOOKUP_GOT_TEMP_FAILURE]	= "temp-failure",325	[DNS_LOOKUP_GOT_NS_FAILURE]	= "ns-failure",326	[NR__dns_lookup_status]		= "[weird]"327};328 329/*330 * Display the list of Volume Location servers we're using for a cell.331 */332static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v)333{334	const struct afs_vl_seq_net_private *priv = m->private;335	const struct afs_vlserver_list *vllist = priv->vllist;336	const struct afs_vlserver_entry *entry;337	const struct afs_vlserver *vlserver;338	const struct afs_addr_list *alist;339	int i;340 341	if (v == SEQ_START_TOKEN) {342		seq_printf(m, "# source %s, status %s\n",343			   dns_record_sources[vllist ? vllist->source : 0],344			   dns_lookup_statuses[vllist ? vllist->status : 0]);345		return 0;346	}347 348	entry = v;349	vlserver = entry->server;350	alist = rcu_dereference(vlserver->addresses);351 352	seq_printf(m, "%s [p=%hu w=%hu s=%s,%s]:\n",353		   vlserver->name, entry->priority, entry->weight,354		   dns_record_sources[alist ? alist->source : entry->source],355		   dns_lookup_statuses[alist ? alist->status : entry->status]);356	if (alist) {357		for (i = 0; i < alist->nr_addrs; i++)358			seq_printf(m, " %c %pISpc\n",359				   alist->preferred == i ? '>' : '-',360				   rxrpc_kernel_remote_addr(alist->addrs[i].peer));361	}362	seq_printf(m, " info: fl=%lx rtt=%d\n", vlserver->flags, vlserver->rtt);363	seq_printf(m, " probe: fl=%x e=%d ac=%d out=%d\n",364		   vlserver->probe.flags, vlserver->probe.error,365		   vlserver->probe.abort_code,366		   atomic_read(&vlserver->probe_outstanding));367	return 0;368}369 370static void *afs_proc_cell_vlservers_start(struct seq_file *m, loff_t *_pos)371	__acquires(rcu)372{373	struct afs_vl_seq_net_private *priv = m->private;374	struct afs_vlserver_list *vllist;375	struct afs_cell *cell = pde_data(file_inode(m->file));376	loff_t pos = *_pos;377 378	rcu_read_lock();379 380	vllist = rcu_dereference(cell->vl_servers);381	priv->vllist = vllist;382 383	if (pos < 0)384		*_pos = pos = 0;385	if (pos == 0)386		return SEQ_START_TOKEN;387 388	if (pos - 1 >= vllist->nr_servers)389		return NULL;390 391	return &vllist->servers[pos - 1];392}393 394static void *afs_proc_cell_vlservers_next(struct seq_file *m, void *v,395					  loff_t *_pos)396{397	struct afs_vl_seq_net_private *priv = m->private;398	struct afs_vlserver_list *vllist = priv->vllist;399	loff_t pos;400 401	pos = *_pos;402	pos++;403	*_pos = pos;404	if (!vllist || pos - 1 >= vllist->nr_servers)405		return NULL;406 407	return &vllist->servers[pos - 1];408}409 410static void afs_proc_cell_vlservers_stop(struct seq_file *m, void *v)411	__releases(rcu)412{413	rcu_read_unlock();414}415 416static const struct seq_operations afs_proc_cell_vlservers_ops = {417	.start	= afs_proc_cell_vlservers_start,418	.next	= afs_proc_cell_vlservers_next,419	.stop	= afs_proc_cell_vlservers_stop,420	.show	= afs_proc_cell_vlservers_show,421};422 423/*424 * Display the list of fileservers we're using within a namespace.425 */426static int afs_proc_servers_show(struct seq_file *m, void *v)427{428	struct afs_endpoint_state *estate;429	struct afs_addr_list *alist;430	struct afs_server *server;431	unsigned long failed;432	int i;433 434	if (v == SEQ_START_TOKEN) {435		seq_puts(m, "UUID                                 REF ACT CELL\n");436		return 0;437	}438 439	server = list_entry(v, struct afs_server, proc_link);440	estate = rcu_dereference(server->endpoint_state);441	alist = estate->addresses;442	seq_printf(m, "%pU %3d %3d %s\n",443		   &server->uuid,444		   refcount_read(&server->ref),445		   atomic_read(&server->active),446		   server->cell->name);447	seq_printf(m, "  - info: fl=%lx rtt=%u\n",448		   server->flags, server->rtt);449	seq_printf(m, "  - probe: last=%d\n",450		   (int)(jiffies - server->probed_at) / HZ);451	failed = estate->failed_set;452	seq_printf(m, "  - ESTATE pq=%x np=%u rsp=%lx f=%lx\n",453		   estate->probe_seq, atomic_read(&estate->nr_probing),454		   estate->responsive_set, estate->failed_set);455	seq_printf(m, "  - ALIST v=%u ap=%u\n",456		   alist->version, alist->addr_pref_version);457	for (i = 0; i < alist->nr_addrs; i++) {458		const struct afs_address *addr = &alist->addrs[i];459 460		seq_printf(m, "    [%x] %pISpc%s rtt=%d err=%d p=%u\n",461			   i, rxrpc_kernel_remote_addr(addr->peer),462			   alist->preferred == i ? "*" :463			   test_bit(i, &failed) ? "!" : "",464			   rxrpc_kernel_get_srtt(addr->peer),465			   addr->last_error, addr->prio);466	}467	return 0;468}469 470static void *afs_proc_servers_start(struct seq_file *m, loff_t *_pos)471	__acquires(rcu)472{473	rcu_read_lock();474	return seq_hlist_start_head_rcu(&afs_seq2net(m)->fs_proc, *_pos);475}476 477static void *afs_proc_servers_next(struct seq_file *m, void *v, loff_t *_pos)478{479	return seq_hlist_next_rcu(v, &afs_seq2net(m)->fs_proc, _pos);480}481 482static void afs_proc_servers_stop(struct seq_file *m, void *v)483	__releases(rcu)484{485	rcu_read_unlock();486}487 488static const struct seq_operations afs_proc_servers_ops = {489	.start	= afs_proc_servers_start,490	.next	= afs_proc_servers_next,491	.stop	= afs_proc_servers_stop,492	.show	= afs_proc_servers_show,493};494 495/*496 * Display the list of strings that may be substituted for the @sys pathname497 * macro.498 */499static int afs_proc_sysname_show(struct seq_file *m, void *v)500{501	struct afs_net *net = afs_seq2net(m);502	struct afs_sysnames *sysnames = net->sysnames;503	unsigned int i = (unsigned long)v - 1;504 505	if (i < sysnames->nr)506		seq_printf(m, "%s\n", sysnames->subs[i]);507	return 0;508}509 510static void *afs_proc_sysname_start(struct seq_file *m, loff_t *pos)511	__acquires(&net->sysnames_lock)512{513	struct afs_net *net = afs_seq2net(m);514	struct afs_sysnames *names;515 516	read_lock(&net->sysnames_lock);517 518	names = net->sysnames;519	if (*pos >= names->nr)520		return NULL;521	return (void *)(unsigned long)(*pos + 1);522}523 524static void *afs_proc_sysname_next(struct seq_file *m, void *v, loff_t *pos)525{526	struct afs_net *net = afs_seq2net(m);527	struct afs_sysnames *names = net->sysnames;528 529	*pos += 1;530	if (*pos >= names->nr)531		return NULL;532	return (void *)(unsigned long)(*pos + 1);533}534 535static void afs_proc_sysname_stop(struct seq_file *m, void *v)536	__releases(&net->sysnames_lock)537{538	struct afs_net *net = afs_seq2net(m);539 540	read_unlock(&net->sysnames_lock);541}542 543static const struct seq_operations afs_proc_sysname_ops = {544	.start	= afs_proc_sysname_start,545	.next	= afs_proc_sysname_next,546	.stop	= afs_proc_sysname_stop,547	.show	= afs_proc_sysname_show,548};549 550/*551 * Allow the @sys substitution to be configured.552 */553static int afs_proc_sysname_write(struct file *file, char *buf, size_t size)554{555	struct afs_sysnames *sysnames, *kill;556	struct seq_file *m = file->private_data;557	struct afs_net *net = afs_seq2net(m);558	char *s, *p, *sub;559	int ret, len;560 561	sysnames = kzalloc(sizeof(*sysnames), GFP_KERNEL);562	if (!sysnames)563		return -ENOMEM;564	refcount_set(&sysnames->usage, 1);565	kill = sysnames;566 567	p = buf;568	while ((s = strsep(&p, " \t\n"))) {569		len = strlen(s);570		if (len == 0)571			continue;572		ret = -ENAMETOOLONG;573		if (len >= AFSNAMEMAX)574			goto error;575 576		if (len >= 4 &&577		    s[len - 4] == '@' &&578		    s[len - 3] == 's' &&579		    s[len - 2] == 'y' &&580		    s[len - 1] == 's')581			/* Protect against recursion */582			goto invalid;583 584		if (s[0] == '.' &&585		    (len < 2 || (len == 2 && s[1] == '.')))586			goto invalid;587 588		if (memchr(s, '/', len))589			goto invalid;590 591		ret = -EFBIG;592		if (sysnames->nr >= AFS_NR_SYSNAME)593			goto out;594 595		if (strcmp(s, afs_init_sysname) == 0) {596			sub = (char *)afs_init_sysname;597		} else {598			ret = -ENOMEM;599			sub = kmemdup(s, len + 1, GFP_KERNEL);600			if (!sub)601				goto out;602		}603 604		sysnames->subs[sysnames->nr] = sub;605		sysnames->nr++;606	}607 608	if (sysnames->nr == 0) {609		sysnames->subs[0] = sysnames->blank;610		sysnames->nr++;611	}612 613	write_lock(&net->sysnames_lock);614	kill = net->sysnames;615	net->sysnames = sysnames;616	write_unlock(&net->sysnames_lock);617	ret = 0;618out:619	afs_put_sysnames(kill);620	return ret;621 622invalid:623	ret = -EINVAL;624error:625	goto out;626}627 628void afs_put_sysnames(struct afs_sysnames *sysnames)629{630	int i;631 632	if (sysnames && refcount_dec_and_test(&sysnames->usage)) {633		for (i = 0; i < sysnames->nr; i++)634			if (sysnames->subs[i] != afs_init_sysname &&635			    sysnames->subs[i] != sysnames->blank)636				kfree(sysnames->subs[i]);637		kfree(sysnames);638	}639}640 641/*642 * Display general per-net namespace statistics643 */644static int afs_proc_stats_show(struct seq_file *m, void *v)645{646	struct afs_net *net = afs_seq2net_single(m);647 648	seq_puts(m, "kAFS statistics\n");649 650	seq_printf(m, "dir-mgmt: look=%u reval=%u inval=%u relpg=%u\n",651		   atomic_read(&net->n_lookup),652		   atomic_read(&net->n_reval),653		   atomic_read(&net->n_inval),654		   atomic_read(&net->n_relpg));655 656	seq_printf(m, "dir-data: rdpg=%u\n",657		   atomic_read(&net->n_read_dir));658 659	seq_printf(m, "dir-edit: cr=%u rm=%u\n",660		   atomic_read(&net->n_dir_cr),661		   atomic_read(&net->n_dir_rm));662 663	seq_printf(m, "file-rd : n=%u nb=%lu\n",664		   atomic_read(&net->n_fetches),665		   atomic_long_read(&net->n_fetch_bytes));666	seq_printf(m, "file-wr : n=%u nb=%lu\n",667		   atomic_read(&net->n_stores),668		   atomic_long_read(&net->n_store_bytes));669	return 0;670}671 672/*673 * initialise /proc/fs/afs/<cell>/674 */675int afs_proc_cell_setup(struct afs_cell *cell)676{677	struct proc_dir_entry *dir;678	struct afs_net *net = cell->net;679 680	_enter("%p{%s},%p", cell, cell->name, net->proc_afs);681 682	dir = proc_net_mkdir(net->net, cell->name, net->proc_afs);683	if (!dir)684		goto error_dir;685 686	if (!proc_create_net_data("vlservers", 0444, dir,687				  &afs_proc_cell_vlservers_ops,688				  sizeof(struct afs_vl_seq_net_private),689				  cell) ||690	    !proc_create_net_data("volumes", 0444, dir,691				  &afs_proc_cell_volumes_ops,692				  sizeof(struct seq_net_private),693				  cell))694		goto error_tree;695 696	_leave(" = 0");697	return 0;698 699error_tree:700	remove_proc_subtree(cell->name, net->proc_afs);701error_dir:702	_leave(" = -ENOMEM");703	return -ENOMEM;704}705 706/*707 * remove /proc/fs/afs/<cell>/708 */709void afs_proc_cell_remove(struct afs_cell *cell)710{711	struct afs_net *net = cell->net;712 713	_enter("");714	remove_proc_subtree(cell->name, net->proc_afs);715	_leave("");716}717 718/*719 * initialise the /proc/fs/afs/ directory720 */721int afs_proc_init(struct afs_net *net)722{723	struct proc_dir_entry *p;724 725	_enter("");726 727	p = proc_net_mkdir(net->net, "afs", net->net->proc_net);728	if (!p)729		goto error_dir;730 731	if (!proc_create_net_data_write("cells", 0644, p,732					&afs_proc_cells_ops,733					afs_proc_cells_write,734					sizeof(struct seq_net_private),735					NULL) ||736	    !proc_create_net_single_write("rootcell", 0644, p,737					  afs_proc_rootcell_show,738					  afs_proc_rootcell_write,739					  NULL) ||740	    !proc_create_net("servers", 0444, p, &afs_proc_servers_ops,741			     sizeof(struct seq_net_private)) ||742	    !proc_create_net_single("stats", 0444, p, afs_proc_stats_show, NULL) ||743	    !proc_create_net_data_write("sysname", 0644, p,744					&afs_proc_sysname_ops,745					afs_proc_sysname_write,746					sizeof(struct seq_net_private),747					NULL) ||748	    !proc_create_net_single_write("addr_prefs", 0644, p,749					  afs_proc_addr_prefs_show,750					  afs_proc_addr_prefs_write,751					  NULL))752		goto error_tree;753 754	net->proc_afs = p;755	_leave(" = 0");756	return 0;757 758error_tree:759	proc_remove(p);760error_dir:761	_leave(" = -ENOMEM");762	return -ENOMEM;763}764 765/*766 * clean up the /proc/fs/afs/ directory767 */768void afs_proc_cleanup(struct afs_net *net)769{770	proc_remove(net->proc_afs);771	net->proc_afs = NULL;772}773