1 /*
2  * Implementation of the access vector table type.
3  *
4  * Author : Stephen Smalley, <sds@tycho.nsa.gov>
5  */
6 
7 /* Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
8  *
9  *	Added conditional policy language extensions
10  *
11  * Copyright (C) 2003 Tresys Technology, LLC
12  *	This program is free software; you can redistribute it and/or modify
13  *	it under the terms of the GNU General Public License as published by
14  *	the Free Software Foundation, version 2.
15  *
16  * Updated: Yuichi Nakamura <ynakam@hitachisoft.jp>
17  *	Tuned number of hash slots for avtab to reduce memory usage
18  */
19 
20 #include <linux/kernel.h>
21 #include <linux/slab.h>
22 #include <linux/errno.h>
23 #include "avtab.h"
24 #include "policydb.h"
25 
26 static struct kmem_cache *avtab_node_cachep __ro_after_init;
27 static struct kmem_cache *avtab_xperms_cachep __ro_after_init;
28 
29 /* Based on MurmurHash3, written by Austin Appleby and placed in the
30  * public domain.
31  */
avtab_hash(const struct avtab_key * keyp,u32 mask)32 static inline int avtab_hash(const struct avtab_key *keyp, u32 mask)
33 {
34 	static const u32 c1 = 0xcc9e2d51;
35 	static const u32 c2 = 0x1b873593;
36 	static const u32 r1 = 15;
37 	static const u32 r2 = 13;
38 	static const u32 m  = 5;
39 	static const u32 n  = 0xe6546b64;
40 
41 	u32 hash = 0;
42 
43 #define mix(input) do { \
44 		u32 v = input; \
45 		v *= c1; \
46 		v = (v << r1) | (v >> (32 - r1)); \
47 		v *= c2; \
48 		hash ^= v; \
49 		hash = (hash << r2) | (hash >> (32 - r2)); \
50 		hash = hash * m + n; \
51 	} while (0)
52 
53 	mix(keyp->target_class);
54 	mix(keyp->target_type);
55 	mix(keyp->source_type);
56 
57 #undef mix
58 
59 	hash ^= hash >> 16;
60 	hash *= 0x85ebca6b;
61 	hash ^= hash >> 13;
62 	hash *= 0xc2b2ae35;
63 	hash ^= hash >> 16;
64 
65 	return hash & mask;
66 }
67 
68 static struct avtab_node*
avtab_insert_node(struct avtab * h,int hvalue,struct avtab_node * prev,const struct avtab_key * key,const struct avtab_datum * datum)69 avtab_insert_node(struct avtab *h, int hvalue,
70 		  struct avtab_node *prev,
71 		  const struct avtab_key *key, const struct avtab_datum *datum)
72 {
73 	struct avtab_node *newnode;
74 	struct avtab_extended_perms *xperms;
75 	newnode = kmem_cache_zalloc(avtab_node_cachep, GFP_KERNEL);
76 	if (newnode == NULL)
77 		return NULL;
78 	newnode->key = *key;
79 
80 	if (key->specified & AVTAB_XPERMS) {
81 		xperms = kmem_cache_zalloc(avtab_xperms_cachep, GFP_KERNEL);
82 		if (xperms == NULL) {
83 			kmem_cache_free(avtab_node_cachep, newnode);
84 			return NULL;
85 		}
86 		*xperms = *(datum->u.xperms);
87 		newnode->datum.u.xperms = xperms;
88 	} else {
89 		newnode->datum.u.data = datum->u.data;
90 	}
91 
92 	if (prev) {
93 		newnode->next = prev->next;
94 		prev->next = newnode;
95 	} else {
96 		struct avtab_node **n = &h->htable[hvalue];
97 
98 		newnode->next = *n;
99 		*n = newnode;
100 	}
101 
102 	h->nel++;
103 	return newnode;
104 }
105 
avtab_insert(struct avtab * h,const struct avtab_key * key,const struct avtab_datum * datum)106 static int avtab_insert(struct avtab *h, const struct avtab_key *key,
107 			const struct avtab_datum *datum)
108 {
109 	int hvalue;
110 	struct avtab_node *prev, *cur, *newnode;
111 	u16 specified = key->specified & ~(AVTAB_ENABLED|AVTAB_ENABLED_OLD);
112 
113 	if (!h || !h->nslot)
114 		return -EINVAL;
115 
116 	hvalue = avtab_hash(key, h->mask);
117 	for (prev = NULL, cur = h->htable[hvalue];
118 	     cur;
119 	     prev = cur, cur = cur->next) {
120 		if (key->source_type == cur->key.source_type &&
121 		    key->target_type == cur->key.target_type &&
122 		    key->target_class == cur->key.target_class &&
123 		    (specified & cur->key.specified)) {
124 			/* extended perms may not be unique */
125 			if (specified & AVTAB_XPERMS)
126 				break;
127 			return -EEXIST;
128 		}
129 		if (key->source_type < cur->key.source_type)
130 			break;
131 		if (key->source_type == cur->key.source_type &&
132 		    key->target_type < cur->key.target_type)
133 			break;
134 		if (key->source_type == cur->key.source_type &&
135 		    key->target_type == cur->key.target_type &&
136 		    key->target_class < cur->key.target_class)
137 			break;
138 	}
139 
140 	newnode = avtab_insert_node(h, hvalue, prev, key, datum);
141 	if (!newnode)
142 		return -ENOMEM;
143 
144 	return 0;
145 }
146 
147 /* Unlike avtab_insert(), this function allow multiple insertions of the same
148  * key/specified mask into the table, as needed by the conditional avtab.
149  * It also returns a pointer to the node inserted.
150  */
avtab_insert_nonunique(struct avtab * h,const struct avtab_key * key,const struct avtab_datum * datum)151 struct avtab_node *avtab_insert_nonunique(struct avtab *h,
152 					  const struct avtab_key *key,
153 					  const struct avtab_datum *datum)
154 {
155 	int hvalue;
156 	struct avtab_node *prev, *cur;
157 	u16 specified = key->specified & ~(AVTAB_ENABLED|AVTAB_ENABLED_OLD);
158 
159 	if (!h || !h->nslot)
160 		return NULL;
161 	hvalue = avtab_hash(key, h->mask);
162 	for (prev = NULL, cur = h->htable[hvalue];
163 	     cur;
164 	     prev = cur, cur = cur->next) {
165 		if (key->source_type == cur->key.source_type &&
166 		    key->target_type == cur->key.target_type &&
167 		    key->target_class == cur->key.target_class &&
168 		    (specified & cur->key.specified))
169 			break;
170 		if (key->source_type < cur->key.source_type)
171 			break;
172 		if (key->source_type == cur->key.source_type &&
173 		    key->target_type < cur->key.target_type)
174 			break;
175 		if (key->source_type == cur->key.source_type &&
176 		    key->target_type == cur->key.target_type &&
177 		    key->target_class < cur->key.target_class)
178 			break;
179 	}
180 	return avtab_insert_node(h, hvalue, prev, key, datum);
181 }
182 
avtab_search(struct avtab * h,const struct avtab_key * key)183 struct avtab_datum *avtab_search(struct avtab *h, const struct avtab_key *key)
184 {
185 	int hvalue;
186 	struct avtab_node *cur;
187 	u16 specified = key->specified & ~(AVTAB_ENABLED|AVTAB_ENABLED_OLD);
188 
189 	if (!h || !h->nslot)
190 		return NULL;
191 
192 	hvalue = avtab_hash(key, h->mask);
193 	for (cur = h->htable[hvalue]; cur;
194 	     cur = cur->next) {
195 		if (key->source_type == cur->key.source_type &&
196 		    key->target_type == cur->key.target_type &&
197 		    key->target_class == cur->key.target_class &&
198 		    (specified & cur->key.specified))
199 			return &cur->datum;
200 
201 		if (key->source_type < cur->key.source_type)
202 			break;
203 		if (key->source_type == cur->key.source_type &&
204 		    key->target_type < cur->key.target_type)
205 			break;
206 		if (key->source_type == cur->key.source_type &&
207 		    key->target_type == cur->key.target_type &&
208 		    key->target_class < cur->key.target_class)
209 			break;
210 	}
211 
212 	return NULL;
213 }
214 
215 /* This search function returns a node pointer, and can be used in
216  * conjunction with avtab_search_next_node()
217  */
avtab_search_node(struct avtab * h,const struct avtab_key * key)218 struct avtab_node *avtab_search_node(struct avtab *h,
219 				     const struct avtab_key *key)
220 {
221 	int hvalue;
222 	struct avtab_node *cur;
223 	u16 specified = key->specified & ~(AVTAB_ENABLED|AVTAB_ENABLED_OLD);
224 
225 	if (!h || !h->nslot)
226 		return NULL;
227 
228 	hvalue = avtab_hash(key, h->mask);
229 	for (cur = h->htable[hvalue]; cur;
230 	     cur = cur->next) {
231 		if (key->source_type == cur->key.source_type &&
232 		    key->target_type == cur->key.target_type &&
233 		    key->target_class == cur->key.target_class &&
234 		    (specified & cur->key.specified))
235 			return cur;
236 
237 		if (key->source_type < cur->key.source_type)
238 			break;
239 		if (key->source_type == cur->key.source_type &&
240 		    key->target_type < cur->key.target_type)
241 			break;
242 		if (key->source_type == cur->key.source_type &&
243 		    key->target_type == cur->key.target_type &&
244 		    key->target_class < cur->key.target_class)
245 			break;
246 	}
247 	return NULL;
248 }
249 
250 struct avtab_node*
avtab_search_node_next(struct avtab_node * node,int specified)251 avtab_search_node_next(struct avtab_node *node, int specified)
252 {
253 	struct avtab_node *cur;
254 
255 	if (!node)
256 		return NULL;
257 
258 	specified &= ~(AVTAB_ENABLED|AVTAB_ENABLED_OLD);
259 	for (cur = node->next; cur; cur = cur->next) {
260 		if (node->key.source_type == cur->key.source_type &&
261 		    node->key.target_type == cur->key.target_type &&
262 		    node->key.target_class == cur->key.target_class &&
263 		    (specified & cur->key.specified))
264 			return cur;
265 
266 		if (node->key.source_type < cur->key.source_type)
267 			break;
268 		if (node->key.source_type == cur->key.source_type &&
269 		    node->key.target_type < cur->key.target_type)
270 			break;
271 		if (node->key.source_type == cur->key.source_type &&
272 		    node->key.target_type == cur->key.target_type &&
273 		    node->key.target_class < cur->key.target_class)
274 			break;
275 	}
276 	return NULL;
277 }
278 
avtab_destroy(struct avtab * h)279 void avtab_destroy(struct avtab *h)
280 {
281 	int i;
282 	struct avtab_node *cur, *temp;
283 
284 	if (!h)
285 		return;
286 
287 	for (i = 0; i < h->nslot; i++) {
288 		cur = h->htable[i];
289 		while (cur) {
290 			temp = cur;
291 			cur = cur->next;
292 			if (temp->key.specified & AVTAB_XPERMS)
293 				kmem_cache_free(avtab_xperms_cachep,
294 						temp->datum.u.xperms);
295 			kmem_cache_free(avtab_node_cachep, temp);
296 		}
297 	}
298 	kvfree(h->htable);
299 	h->htable = NULL;
300 	h->nel = 0;
301 	h->nslot = 0;
302 	h->mask = 0;
303 }
304 
avtab_init(struct avtab * h)305 void avtab_init(struct avtab *h)
306 {
307 	h->htable = NULL;
308 	h->nel = 0;
309 	h->nslot = 0;
310 	h->mask = 0;
311 }
312 
avtab_alloc_common(struct avtab * h,u32 nslot)313 static int avtab_alloc_common(struct avtab *h, u32 nslot)
314 {
315 	if (!nslot)
316 		return 0;
317 
318 	h->htable = kvcalloc(nslot, sizeof(void *), GFP_KERNEL);
319 	if (!h->htable)
320 		return -ENOMEM;
321 
322 	h->nslot = nslot;
323 	h->mask = nslot - 1;
324 	return 0;
325 }
326 
avtab_alloc(struct avtab * h,u32 nrules)327 int avtab_alloc(struct avtab *h, u32 nrules)
328 {
329 	int rc;
330 	u32 nslot = 0;
331 
332 	if (nrules != 0) {
333 		u32 shift = 1;
334 		u32 work = nrules >> 3;
335 		while (work) {
336 			work >>= 1;
337 			shift++;
338 		}
339 		nslot = 1 << shift;
340 		if (nslot > MAX_AVTAB_HASH_BUCKETS)
341 			nslot = MAX_AVTAB_HASH_BUCKETS;
342 
343 		rc = avtab_alloc_common(h, nslot);
344 		if (rc)
345 			return rc;
346 	}
347 
348 	pr_debug("SELinux: %d avtab hash slots, %d rules.\n", nslot, nrules);
349 	return 0;
350 }
351 
avtab_alloc_dup(struct avtab * new,const struct avtab * orig)352 int avtab_alloc_dup(struct avtab *new, const struct avtab *orig)
353 {
354 	return avtab_alloc_common(new, orig->nslot);
355 }
356 
avtab_hash_eval(struct avtab * h,char * tag)357 void avtab_hash_eval(struct avtab *h, char *tag)
358 {
359 	int i, chain_len, slots_used, max_chain_len;
360 	unsigned long long chain2_len_sum;
361 	struct avtab_node *cur;
362 
363 	slots_used = 0;
364 	max_chain_len = 0;
365 	chain2_len_sum = 0;
366 	for (i = 0; i < h->nslot; i++) {
367 		cur = h->htable[i];
368 		if (cur) {
369 			slots_used++;
370 			chain_len = 0;
371 			while (cur) {
372 				chain_len++;
373 				cur = cur->next;
374 			}
375 
376 			if (chain_len > max_chain_len)
377 				max_chain_len = chain_len;
378 			chain2_len_sum += chain_len * chain_len;
379 		}
380 	}
381 
382 	pr_debug("SELinux: %s:  %d entries and %d/%d buckets used, "
383 	       "longest chain length %d sum of chain length^2 %llu\n",
384 	       tag, h->nel, slots_used, h->nslot, max_chain_len,
385 	       chain2_len_sum);
386 }
387 
388 static const uint16_t spec_order[] = {
389 	AVTAB_ALLOWED,
390 	AVTAB_AUDITDENY,
391 	AVTAB_AUDITALLOW,
392 	AVTAB_TRANSITION,
393 	AVTAB_CHANGE,
394 	AVTAB_MEMBER,
395 	AVTAB_XPERMS_ALLOWED,
396 	AVTAB_XPERMS_AUDITALLOW,
397 	AVTAB_XPERMS_DONTAUDIT
398 };
399 
avtab_read_item(struct avtab * a,void * fp,struct policydb * pol,int (* insertf)(struct avtab * a,const struct avtab_key * k,const struct avtab_datum * d,void * p),void * p)400 int avtab_read_item(struct avtab *a, void *fp, struct policydb *pol,
401 		    int (*insertf)(struct avtab *a, const struct avtab_key *k,
402 				   const struct avtab_datum *d, void *p),
403 		    void *p)
404 {
405 	__le16 buf16[4];
406 	u16 enabled;
407 	u32 items, items2, val, vers = pol->policyvers;
408 	struct avtab_key key;
409 	struct avtab_datum datum;
410 	struct avtab_extended_perms xperms;
411 	__le32 buf32[ARRAY_SIZE(xperms.perms.p)];
412 	int i, rc;
413 	unsigned set;
414 
415 	memset(&key, 0, sizeof(struct avtab_key));
416 	memset(&datum, 0, sizeof(struct avtab_datum));
417 
418 	if (vers < POLICYDB_VERSION_AVTAB) {
419 		rc = next_entry(buf32, fp, sizeof(u32));
420 		if (rc) {
421 			pr_err("SELinux: avtab: truncated entry\n");
422 			return rc;
423 		}
424 		items2 = le32_to_cpu(buf32[0]);
425 		if (items2 > ARRAY_SIZE(buf32)) {
426 			pr_err("SELinux: avtab: entry overflow\n");
427 			return -EINVAL;
428 
429 		}
430 		rc = next_entry(buf32, fp, sizeof(u32)*items2);
431 		if (rc) {
432 			pr_err("SELinux: avtab: truncated entry\n");
433 			return rc;
434 		}
435 		items = 0;
436 
437 		val = le32_to_cpu(buf32[items++]);
438 		key.source_type = (u16)val;
439 		if (key.source_type != val) {
440 			pr_err("SELinux: avtab: truncated source type\n");
441 			return -EINVAL;
442 		}
443 		val = le32_to_cpu(buf32[items++]);
444 		key.target_type = (u16)val;
445 		if (key.target_type != val) {
446 			pr_err("SELinux: avtab: truncated target type\n");
447 			return -EINVAL;
448 		}
449 		val = le32_to_cpu(buf32[items++]);
450 		key.target_class = (u16)val;
451 		if (key.target_class != val) {
452 			pr_err("SELinux: avtab: truncated target class\n");
453 			return -EINVAL;
454 		}
455 
456 		val = le32_to_cpu(buf32[items++]);
457 		enabled = (val & AVTAB_ENABLED_OLD) ? AVTAB_ENABLED : 0;
458 
459 		if (!(val & (AVTAB_AV | AVTAB_TYPE))) {
460 			pr_err("SELinux: avtab: null entry\n");
461 			return -EINVAL;
462 		}
463 		if ((val & AVTAB_AV) &&
464 		    (val & AVTAB_TYPE)) {
465 			pr_err("SELinux: avtab: entry has both access vectors and types\n");
466 			return -EINVAL;
467 		}
468 		if (val & AVTAB_XPERMS) {
469 			pr_err("SELinux: avtab: entry has extended permissions\n");
470 			return -EINVAL;
471 		}
472 
473 		for (i = 0; i < ARRAY_SIZE(spec_order); i++) {
474 			if (val & spec_order[i]) {
475 				key.specified = spec_order[i] | enabled;
476 				datum.u.data = le32_to_cpu(buf32[items++]);
477 				rc = insertf(a, &key, &datum, p);
478 				if (rc)
479 					return rc;
480 			}
481 		}
482 
483 		if (items != items2) {
484 			pr_err("SELinux: avtab: entry only had %d items, expected %d\n",
485 			       items2, items);
486 			return -EINVAL;
487 		}
488 		return 0;
489 	}
490 
491 	rc = next_entry(buf16, fp, sizeof(u16)*4);
492 	if (rc) {
493 		pr_err("SELinux: avtab: truncated entry\n");
494 		return rc;
495 	}
496 
497 	items = 0;
498 	key.source_type = le16_to_cpu(buf16[items++]);
499 	key.target_type = le16_to_cpu(buf16[items++]);
500 	key.target_class = le16_to_cpu(buf16[items++]);
501 	key.specified = le16_to_cpu(buf16[items++]);
502 
503 	if (!policydb_type_isvalid(pol, key.source_type) ||
504 	    !policydb_type_isvalid(pol, key.target_type) ||
505 	    !policydb_class_isvalid(pol, key.target_class)) {
506 		pr_err("SELinux: avtab: invalid type or class\n");
507 		return -EINVAL;
508 	}
509 
510 	set = 0;
511 	for (i = 0; i < ARRAY_SIZE(spec_order); i++) {
512 		if (key.specified & spec_order[i])
513 			set++;
514 	}
515 	if (!set || set > 1) {
516 		pr_err("SELinux:  avtab:  more than one specifier\n");
517 		return -EINVAL;
518 	}
519 
520 	if ((vers < POLICYDB_VERSION_XPERMS_IOCTL) &&
521 			(key.specified & AVTAB_XPERMS)) {
522 		pr_err("SELinux:  avtab:  policy version %u does not "
523 				"support extended permissions rules and one "
524 				"was specified\n", vers);
525 		return -EINVAL;
526 	} else if (key.specified & AVTAB_XPERMS) {
527 		memset(&xperms, 0, sizeof(struct avtab_extended_perms));
528 		rc = next_entry(&xperms.specified, fp, sizeof(u8));
529 		if (rc) {
530 			pr_err("SELinux: avtab: truncated entry\n");
531 			return rc;
532 		}
533 		rc = next_entry(&xperms.driver, fp, sizeof(u8));
534 		if (rc) {
535 			pr_err("SELinux: avtab: truncated entry\n");
536 			return rc;
537 		}
538 		rc = next_entry(buf32, fp, sizeof(u32)*ARRAY_SIZE(xperms.perms.p));
539 		if (rc) {
540 			pr_err("SELinux: avtab: truncated entry\n");
541 			return rc;
542 		}
543 		for (i = 0; i < ARRAY_SIZE(xperms.perms.p); i++)
544 			xperms.perms.p[i] = le32_to_cpu(buf32[i]);
545 		datum.u.xperms = &xperms;
546 	} else {
547 		rc = next_entry(buf32, fp, sizeof(u32));
548 		if (rc) {
549 			pr_err("SELinux: avtab: truncated entry\n");
550 			return rc;
551 		}
552 		datum.u.data = le32_to_cpu(*buf32);
553 	}
554 	if ((key.specified & AVTAB_TYPE) &&
555 	    !policydb_type_isvalid(pol, datum.u.data)) {
556 		pr_err("SELinux: avtab: invalid type\n");
557 		return -EINVAL;
558 	}
559 	return insertf(a, &key, &datum, p);
560 }
561 
avtab_insertf(struct avtab * a,const struct avtab_key * k,const struct avtab_datum * d,void * p)562 static int avtab_insertf(struct avtab *a, const struct avtab_key *k,
563 			 const struct avtab_datum *d, void *p)
564 {
565 	return avtab_insert(a, k, d);
566 }
567 
avtab_read(struct avtab * a,void * fp,struct policydb * pol)568 int avtab_read(struct avtab *a, void *fp, struct policydb *pol)
569 {
570 	int rc;
571 	__le32 buf[1];
572 	u32 nel, i;
573 
574 
575 	rc = next_entry(buf, fp, sizeof(u32));
576 	if (rc < 0) {
577 		pr_err("SELinux: avtab: truncated table\n");
578 		goto bad;
579 	}
580 	nel = le32_to_cpu(buf[0]);
581 	if (!nel) {
582 		pr_err("SELinux: avtab: table is empty\n");
583 		rc = -EINVAL;
584 		goto bad;
585 	}
586 
587 	rc = avtab_alloc(a, nel);
588 	if (rc)
589 		goto bad;
590 
591 	for (i = 0; i < nel; i++) {
592 		rc = avtab_read_item(a, fp, pol, avtab_insertf, NULL);
593 		if (rc) {
594 			if (rc == -ENOMEM)
595 				pr_err("SELinux: avtab: out of memory\n");
596 			else if (rc == -EEXIST)
597 				pr_err("SELinux: avtab: duplicate entry\n");
598 
599 			goto bad;
600 		}
601 	}
602 
603 	rc = 0;
604 out:
605 	return rc;
606 
607 bad:
608 	avtab_destroy(a);
609 	goto out;
610 }
611 
avtab_write_item(struct policydb * p,const struct avtab_node * cur,void * fp)612 int avtab_write_item(struct policydb *p, const struct avtab_node *cur, void *fp)
613 {
614 	__le16 buf16[4];
615 	__le32 buf32[ARRAY_SIZE(cur->datum.u.xperms->perms.p)];
616 	int rc;
617 	unsigned int i;
618 
619 	buf16[0] = cpu_to_le16(cur->key.source_type);
620 	buf16[1] = cpu_to_le16(cur->key.target_type);
621 	buf16[2] = cpu_to_le16(cur->key.target_class);
622 	buf16[3] = cpu_to_le16(cur->key.specified);
623 	rc = put_entry(buf16, sizeof(u16), 4, fp);
624 	if (rc)
625 		return rc;
626 
627 	if (cur->key.specified & AVTAB_XPERMS) {
628 		rc = put_entry(&cur->datum.u.xperms->specified, sizeof(u8), 1, fp);
629 		if (rc)
630 			return rc;
631 		rc = put_entry(&cur->datum.u.xperms->driver, sizeof(u8), 1, fp);
632 		if (rc)
633 			return rc;
634 		for (i = 0; i < ARRAY_SIZE(cur->datum.u.xperms->perms.p); i++)
635 			buf32[i] = cpu_to_le32(cur->datum.u.xperms->perms.p[i]);
636 		rc = put_entry(buf32, sizeof(u32),
637 				ARRAY_SIZE(cur->datum.u.xperms->perms.p), fp);
638 	} else {
639 		buf32[0] = cpu_to_le32(cur->datum.u.data);
640 		rc = put_entry(buf32, sizeof(u32), 1, fp);
641 	}
642 	if (rc)
643 		return rc;
644 	return 0;
645 }
646 
avtab_write(struct policydb * p,struct avtab * a,void * fp)647 int avtab_write(struct policydb *p, struct avtab *a, void *fp)
648 {
649 	unsigned int i;
650 	int rc = 0;
651 	struct avtab_node *cur;
652 	__le32 buf[1];
653 
654 	buf[0] = cpu_to_le32(a->nel);
655 	rc = put_entry(buf, sizeof(u32), 1, fp);
656 	if (rc)
657 		return rc;
658 
659 	for (i = 0; i < a->nslot; i++) {
660 		for (cur = a->htable[i]; cur;
661 		     cur = cur->next) {
662 			rc = avtab_write_item(p, cur, fp);
663 			if (rc)
664 				return rc;
665 		}
666 	}
667 
668 	return rc;
669 }
670 
avtab_cache_init(void)671 void __init avtab_cache_init(void)
672 {
673 	avtab_node_cachep = kmem_cache_create("avtab_node",
674 					      sizeof(struct avtab_node),
675 					      0, SLAB_PANIC, NULL);
676 	avtab_xperms_cachep = kmem_cache_create("avtab_extended_perms",
677 						sizeof(struct avtab_extended_perms),
678 						0, SLAB_PANIC, NULL);
679 }
680