// SPDX-License-Identifier: GPL-2.0-only
/*
 * Implementation of the policy database.
 *
 * Author : Stephen Smalley, <stephen.smalley.work@gmail.com>
 */

/*
 * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
 *          Support for enhanced MLS infrastructure.
 *          Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
 *
 * Updated: Frank Mayer <mayerf@tresys.com> and
 *          Karl MacMillan <kmacmillan@tresys.com>
 *          Added conditional policy language extensions
 *          Copyright (C) 2003-2004 Tresys Technology, LLC
 *
 * Updated: Hewlett-Packard <paul@paul-moore.com>
 *          Added support for the policy capability bitmap
 *          Copyright (C) 2007 Hewlett-Packard Development Company, L.P.
 *
 * Update: Mellanox Techonologies
 *         Added Infiniband support
 *         Copyright (C) 2016 Mellanox Techonologies
 */

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/audit.h>
#include <linux/sort.h>
#include "security.h"

#include "policydb.h"
#include "conditional.h"
#include "mls.h"
#include "services.h"

#ifdef CONFIG_SECURITY_SELINUX_DEBUG
/* clang-format off */
static const char *const symtab_name[SYM_NUM] = {
	"common prefixes",
	"classes",
	"roles",
	"types",
	"users",
	"bools",
	"levels",
	"categories",
};
/* clang-format off */
#endif

struct policydb_compat_info {
	unsigned int version;
	unsigned int sym_num;
	unsigned int ocon_num;
};

/* These need to be updated if SYM_NUM or OCON_NUM changes */
static const struct policydb_compat_info policydb_compat[] = {
	{
		.version = POLICYDB_VERSION_BASE,
		.sym_num = SYM_NUM - 3,
		.ocon_num = OCON_NUM - 3,
	},
	{
		.version = POLICYDB_VERSION_BOOL,
		.sym_num = SYM_NUM - 2,
		.ocon_num = OCON_NUM - 3,
	},
	{
		.version = POLICYDB_VERSION_IPV6,
		.sym_num = SYM_NUM - 2,
		.ocon_num = OCON_NUM - 2,
	},
	{
		.version = POLICYDB_VERSION_NLCLASS,
		.sym_num = SYM_NUM - 2,
		.ocon_num = OCON_NUM - 2,
	},
	{
		.version = POLICYDB_VERSION_MLS,
		.sym_num = SYM_NUM,
		.ocon_num = OCON_NUM - 2,
	},
	{
		.version = POLICYDB_VERSION_AVTAB,
		.sym_num = SYM_NUM,
		.ocon_num = OCON_NUM - 2,
	},
	{
		.version = POLICYDB_VERSION_RANGETRANS,
		.sym_num = SYM_NUM,
		.ocon_num = OCON_NUM - 2,
	},
	{
		.version = POLICYDB_VERSION_POLCAP,
		.sym_num = SYM_NUM,
		.ocon_num = OCON_NUM - 2,
	},
	{
		.version = POLICYDB_VERSION_PERMISSIVE,
		.sym_num = SYM_NUM,
		.ocon_num = OCON_NUM - 2,
	},
	{
		.version = POLICYDB_VERSION_BOUNDARY,
		.sym_num = SYM_NUM,
		.ocon_num = OCON_NUM - 2,
	},
	{
		.version = POLICYDB_VERSION_FILENAME_TRANS,
		.sym_num = SYM_NUM,
		.ocon_num = OCON_NUM - 2,
	},
	{
		.version = POLICYDB_VERSION_ROLETRANS,
		.sym_num = SYM_NUM,
		.ocon_num = OCON_NUM - 2,
	},
	{
		.version = POLICYDB_VERSION_NEW_OBJECT_DEFAULTS,
		.sym_num = SYM_NUM,
		.ocon_num = OCON_NUM - 2,
	},
	{
		.version = POLICYDB_VERSION_DEFAULT_TYPE,
		.sym_num = SYM_NUM,
		.ocon_num = OCON_NUM - 2,
	},
	{
		.version = POLICYDB_VERSION_CONSTRAINT_NAMES,
		.sym_num = SYM_NUM,
		.ocon_num = OCON_NUM - 2,
	},
	{
		.version = POLICYDB_VERSION_XPERMS_IOCTL,
		.sym_num = SYM_NUM,
		.ocon_num = OCON_NUM - 2,
	},
	{
		.version = POLICYDB_VERSION_INFINIBAND,
		.sym_num = SYM_NUM,
		.ocon_num = OCON_NUM,
	},
	{
		.version = POLICYDB_VERSION_GLBLUB,
		.sym_num = SYM_NUM,
		.ocon_num = OCON_NUM,
	},
	{
		.version = POLICYDB_VERSION_COMP_FTRANS,
		.sym_num = SYM_NUM,
		.ocon_num = OCON_NUM,
	},
	{
		.version = POLICYDB_VERSION_COND_XPERMS,
		.sym_num = SYM_NUM,
		.ocon_num = OCON_NUM,
	},
	{
		.version = POLICYDB_VERSION_NEVERAUDIT,
		.sym_num = SYM_NUM,
		.ocon_num = OCON_NUM,
	},
};

static const struct policydb_compat_info *
policydb_lookup_compat(unsigned int version)
{
	unsigned int i;

	for (i = 0; i < ARRAY_SIZE(policydb_compat); i++) {
		if (policydb_compat[i].version == version)
			return &policydb_compat[i];
	}

	return NULL;
}

/*
 * The following *_destroy functions are used to
 * free any memory allocated for each kind of
 * symbol data in the policy database.
 */

static int perm_destroy(void *key, void *datum, void *p)
{
	kfree(key);
	kfree(datum);
	return 0;
}

static int common_destroy(void *key, void *datum, void *p)
{
	struct common_datum *comdatum;

	kfree(key);
	if (datum) {
		comdatum = datum;
		hashtab_map(&comdatum->permissions.table, perm_destroy, NULL);
		hashtab_destroy(&comdatum->permissions.table);
	}
	kfree(datum);
	return 0;
}

static void constraint_expr_destroy(struct constraint_expr *expr)
{
	if (expr) {
		ebitmap_destroy(&expr->names);
		if (expr->type_names) {
			ebitmap_destroy(&expr->type_names->types);
			ebitmap_destroy(&expr->type_names->negset);
			kfree(expr->type_names);
		}
		kfree(expr);
	}
}

static int cls_destroy(void *key, void *datum, void *p)
{
	struct class_datum *cladatum;
	struct constraint_node *constraint, *ctemp;
	struct constraint_expr *e, *etmp;

	kfree(key);
	if (datum) {
		cladatum = datum;
		hashtab_map(&cladatum->permissions.table, perm_destroy, NULL);
		hashtab_destroy(&cladatum->permissions.table);
		constraint = cladatum->constraints;
		while (constraint) {
			e = constraint->expr;
			while (e) {
				etmp = e;
				e = e->next;
				constraint_expr_destroy(etmp);
			}
			ctemp = constraint;
			constraint = constraint->next;
			kfree(ctemp);
		}

		constraint = cladatum->validatetrans;
		while (constraint) {
			e = constraint->expr;
			while (e) {
				etmp = e;
				e = e->next;
				constraint_expr_destroy(etmp);
			}
			ctemp = constraint;
			constraint = constraint->next;
			kfree(ctemp);
		}
		kfree(cladatum->comkey);
	}
	kfree(datum);
	return 0;
}

static int role_destroy(void *key, void *datum, void *p)
{
	struct role_datum *role;

	kfree(key);
	if (datum) {
		role = datum;
		ebitmap_destroy(&role->dominates);
		ebitmap_destroy(&role->types);
	}
	kfree(datum);
	return 0;
}

static int type_destroy(void *key, void *datum, void *p)
{
	kfree(key);
	kfree(datum);
	return 0;
}

static int user_destroy(void *key, void *datum, void *p)
{
	struct user_datum *usrdatum;

	kfree(key);
	if (datum) {
		usrdatum = datum;
		ebitmap_destroy(&usrdatum->roles);
		ebitmap_destroy(&usrdatum->range.level[0].cat);
		ebitmap_destroy(&usrdatum->range.level[1].cat);
		ebitmap_destroy(&usrdatum->dfltlevel.cat);
	}
	kfree(datum);
	return 0;
}

static int sens_destroy(void *key, void *datum, void *p)
{
	struct level_datum *levdatum;

	kfree(key);
	if (datum) {
		levdatum = datum;
		ebitmap_destroy(&levdatum->level.cat);
	}
	kfree(datum);
	return 0;
}

static int cat_destroy(void *key, void *datum, void *p)
{
	kfree(key);
	kfree(datum);
	return 0;
}

/* clang-format off */
static int (*const destroy_f[SYM_NUM])(void *key, void *datum, void *datap) = {
	common_destroy,
	cls_destroy,
	role_destroy,
	type_destroy,
	user_destroy,
	cond_destroy_bool,
	sens_destroy,
	cat_destroy,
};
/* clang-format on */

static int filenametr_destroy(void *key, void *datum, void *p)
{
	struct filename_trans_key *ft = key;
	struct filename_trans_datum *next, *d = datum;

	kfree(ft->name);
	kfree(key);
	do {
		ebitmap_destroy(&d->stypes);
		next = d->next;
		kfree(d);
		d = next;
	} while (unlikely(d));
	cond_resched();
	return 0;
}

static int range_tr_destroy(void *key, void *datum, void *p)
{
	struct mls_range *rt = datum;

	kfree(key);
	ebitmap_destroy(&rt->level[0].cat);
	ebitmap_destroy(&rt->level[1].cat);
	kfree(datum);
	cond_resched();
	return 0;
}

static int role_tr_destroy(void *key, void *datum, void *p)
{
	kfree(key);
	kfree(datum);
	return 0;
}

static void ocontext_destroy(struct ocontext *c, unsigned int i)
{
	if (!c)
		return;

	context_destroy(&c->context[0]);
	context_destroy(&c->context[1]);
	if (i == OCON_ISID || i == OCON_FS || i == OCON_NETIF ||
	    i == OCON_FSUSE)
		kfree(c->u.name);
	kfree(c);
}

/*
 * Initialize the role table.
 */
static int roles_init(struct policydb *p)
{
	char *key = NULL;
	int rc;
	struct role_datum *role;

	role = kzalloc_obj(*role);
	if (!role)
		return -ENOMEM;

	rc = -EINVAL;
	role->value = ++p->p_roles.nprim;
	if (role->value != OBJECT_R_VAL)
		goto out;

	rc = -ENOMEM;
	key = kstrdup(OBJECT_R, GFP_KERNEL);
	if (!key)
		goto out;

	rc = symtab_insert(&p->p_roles, key, role);
	if (rc)
		goto out;

	return 0;
out:
	kfree(key);
	kfree(role);
	return rc;
}

static u32 filenametr_hash(const void *k)
{
	const struct filename_trans_key *ft = k;
	unsigned long salt = ft->ttype ^ ft->tclass;

	return full_name_hash((void *)salt, ft->name, strlen(ft->name));
}

static int filenametr_cmp(const void *k1, const void *k2)
{
	const struct filename_trans_key *ft1 = k1;
	const struct filename_trans_key *ft2 = k2;
	int v;

	v = cmp_int(ft1->ttype, ft2->ttype);
	if (v)
		return v;

	v = cmp_int(ft1->tclass, ft2->tclass);
	if (v)
		return v;

	return strcmp(ft1->name, ft2->name);
}

static const struct hashtab_key_params filenametr_key_params = {
	.hash = filenametr_hash,
	.cmp = filenametr_cmp,
};

struct filename_trans_datum *
policydb_filenametr_search(struct policydb *p, struct filename_trans_key *key)
{
	return hashtab_search(&p->filename_trans, key, filenametr_key_params);
}

static u32 rangetr_hash(const void *k)
{
	const struct range_trans *key = k;

	return key->source_type + (key->target_type << 3) +
	       (key->target_class << 5);
}

static int rangetr_cmp(const void *k1, const void *k2)
{
	const struct range_trans *key1 = k1, *key2 = k2;
	int v;

	v = cmp_int(key1->source_type, key2->source_type);
	if (v)
		return v;

	v = cmp_int(key1->target_type, key2->target_type);
	if (v)
		return v;

	v = cmp_int(key1->target_class, key2->target_class);

	return v;
}

static const struct hashtab_key_params rangetr_key_params = {
	.hash = rangetr_hash,
	.cmp = rangetr_cmp,
};

struct mls_range *policydb_rangetr_search(struct policydb *p,
					  struct range_trans *key)
{
	return hashtab_search(&p->range_tr, key, rangetr_key_params);
}

static u32 role_trans_hash(const void *k)
{
	const struct role_trans_key *key = k;

	return jhash_3words(key->role, key->type,
			    (u32)key->tclass << 16 | key->tclass, 0);
}

static int role_trans_cmp(const void *k1, const void *k2)
{
	const struct role_trans_key *key1 = k1, *key2 = k2;
	int v;

	v = cmp_int(key1->role, key2->role);
	if (v)
		return v;

	v = cmp_int(key1->type, key2->type);
	if (v)
		return v;

	return cmp_int(key1->tclass, key2->tclass);
}

static const struct hashtab_key_params roletr_key_params = {
	.hash = role_trans_hash,
	.cmp = role_trans_cmp,
};

struct role_trans_datum *policydb_roletr_search(struct policydb *p,
						struct role_trans_key *key)
{
	return hashtab_search(&p->role_tr, key, roletr_key_params);
}

/*
 * Initialize a policy database structure.
 */
static void policydb_init(struct policydb *p)
{
	memset(p, 0, sizeof(*p));

	avtab_init(&p->te_avtab);
	cond_policydb_init(p);

	ebitmap_init(&p->filename_trans_ttypes);
	ebitmap_init(&p->policycaps);
	ebitmap_init(&p->permissive_map);
	ebitmap_init(&p->neveraudit_map);
}

/*
 * The following *_index functions are used to
 * define the val_to_name and val_to_struct arrays
 * in a policy database structure.  The val_to_name
 * arrays are used when converting security context
 * structures into string representations.  The
 * val_to_struct arrays are used when the attributes
 * of a class, role, or user are needed.
 */

static int common_index(void *key, void *datum, void *datap)
{
	struct policydb *p;
	struct common_datum *comdatum;

	comdatum = datum;
	p = datap;
	if (!comdatum->value || comdatum->value > p->p_commons.nprim)
		return -EINVAL;

	p->sym_val_to_name[SYM_COMMONS][comdatum->value - 1] = key;

	return 0;
}

static int class_index(void *key, void *datum, void *datap)
{
	struct policydb *p;
	struct class_datum *cladatum;

	cladatum = datum;
	p = datap;
	if (!cladatum->value || cladatum->value > p->p_classes.nprim)
		return -EINVAL;

	p->sym_val_to_name[SYM_CLASSES][cladatum->value - 1] = key;
	p->class_val_to_struct[cladatum->value - 1] = cladatum;
	return 0;
}

static int role_index(void *key, void *datum, void *datap)
{
	struct policydb *p;
	struct role_datum *role;

	role = datum;
	p = datap;
	if (!role->value || role->value > p->p_roles.nprim ||
	    role->bounds > p->p_roles.nprim)
		return -EINVAL;

	p->sym_val_to_name[SYM_ROLES][role->value - 1] = key;
	p->role_val_to_struct[role->value - 1] = role;
	return 0;
}

static int type_index(void *key, void *datum, void *datap)
{
	struct policydb *p;
	struct type_datum *typdatum;

	typdatum = datum;
	p = datap;

	if (typdatum->primary) {
		if (!typdatum->value || typdatum->value > p->p_types.nprim ||
		    typdatum->bounds > p->p_types.nprim)
			return -EINVAL;
		p->sym_val_to_name[SYM_TYPES][typdatum->value - 1] = key;
		p->type_val_to_struct[typdatum->value - 1] = typdatum;
	}

	return 0;
}

static int user_index(void *key, void *datum, void *datap)
{
	struct policydb *p;
	struct user_datum *usrdatum;

	usrdatum = datum;
	p = datap;
	if (!usrdatum->value || usrdatum->value > p->p_users.nprim ||
	    usrdatum->bounds > p->p_users.nprim)
		return -EINVAL;

	p->sym_val_to_name[SYM_USERS][usrdatum->value - 1] = key;
	p->user_val_to_struct[usrdatum->value - 1] = usrdatum;
	return 0;
}

static int sens_index(void *key, void *datum, void *datap)
{
	struct policydb *p;
	struct level_datum *levdatum;

	levdatum = datum;
	p = datap;

	if (!levdatum->level.sens || levdatum->level.sens > p->p_levels.nprim)
		return -EINVAL;

	if (!levdatum->isalias)
		p->sym_val_to_name[SYM_LEVELS][levdatum->level.sens - 1] = key;

	return 0;
}

static int cat_index(void *key, void *datum, void *datap)
{
	struct policydb *p;
	struct cat_datum *catdatum;

	catdatum = datum;
	p = datap;

	if (!catdatum->value || catdatum->value > p->p_cats.nprim)
		return -EINVAL;

	if (!catdatum->isalias)
		p->sym_val_to_name[SYM_CATS][catdatum->value - 1] = key;

	return 0;
}

static int sens_cat_index_check(void *key, void *datum, void *datap)
{
	struct policydb *p = datap;
	struct level_datum *levdatum = datum;
	struct ebitmap_node *node;
	u32 bit;

	ebitmap_for_each_positive_bit(&levdatum->level.cat, node, bit) {
		if (bit >= p->p_cats.nprim || !sym_name(p, SYM_CATS, bit)) {
			pr_err("SELinux: sensitivity %s allows undefined category %u\n",
				(const char *)key, bit + 1);
			return -EINVAL;
		}
	}
	return 0;
}

/* clang-format off */
static int (*const index_f[SYM_NUM])(void *key, void *datum, void *datap) = {
	common_index,
	class_index,
	role_index,
	type_index,
	user_index,
	cond_index_bool,
	sens_index,
	cat_index,
};
/* clang-format on */

#ifdef CONFIG_SECURITY_SELINUX_DEBUG
static void hash_eval(struct hashtab *h, const char *hash_name,
		      const char *hash_details)
{
	struct hashtab_info info;

	hashtab_stat(h, &info);
	pr_debug(
		"SELinux: %s%s%s:  %d entries and %d/%d buckets used, longest chain length %d, sum of chain length^2 %llu\n",
		hash_name, hash_details ? "@" : "", hash_details ?: "", h->nel,
		info.slots_used, h->size, info.max_chain_len,
		info.chain2_len_sum);
}

static void symtab_hash_eval(struct symtab *s)
{
	int i;

	for (i = 0; i < SYM_NUM; i++)
		hash_eval(&s[i].table, symtab_name[i], NULL);
}

#else
static inline void hash_eval(struct hashtab *h, const char *hash_name,
			     const char *hash_details)
{
}
static inline void symtab_hash_eval(struct symtab *s)
{
}
#endif /* CONFIG_SECURITY_SELINUX_DEBUG */

/*
 * Define the other val_to_name and val_to_struct arrays
 * in a policy database structure.
 *
 * Caller must clean up on failure.
 */
static int policydb_index(struct policydb *p)
{
	int i, rc;
	u32 v;

	if (p->mls_enabled)
		pr_debug(
			"SELinux:  %d users, %d roles, %d types, %d bools, %d sens, %d cats\n",
			p->p_users.nprim, p->p_roles.nprim, p->p_types.nprim,
			p->p_bools.nprim, p->p_levels.nprim, p->p_cats.nprim);
	else
		pr_debug("SELinux:  %d users, %d roles, %d types, %d bools\n",
			 p->p_users.nprim, p->p_roles.nprim, p->p_types.nprim,
			 p->p_bools.nprim);

	pr_debug("SELinux:  %d classes, %d rules\n", p->p_classes.nprim,
		 p->te_avtab.nel);

	symtab_hash_eval(p->symtab);

	p->class_val_to_struct = kzalloc_objs(*p->class_val_to_struct,
					      p->p_classes.nprim);
	if (!p->class_val_to_struct)
		return -ENOMEM;

	p->role_val_to_struct = kzalloc_objs(*p->role_val_to_struct,
					     p->p_roles.nprim);
	if (!p->role_val_to_struct)
		return -ENOMEM;

	p->user_val_to_struct = kzalloc_objs(*p->user_val_to_struct,
					     p->p_users.nprim);
	if (!p->user_val_to_struct)
		return -ENOMEM;

	p->type_val_to_struct = kvzalloc_objs(*p->type_val_to_struct,
					      p->p_types.nprim);
	if (!p->type_val_to_struct)
		return -ENOMEM;

	rc = cond_init_bool_indexes(p);
	if (rc)
		goto out;

	for (i = 0; i < SYM_NUM; i++) {
		p->sym_val_to_name[i] = kvcalloc(p->symtab[i].nprim,
						 sizeof(char *), GFP_KERNEL);
		if (!p->sym_val_to_name[i])
			return -ENOMEM;

		rc = hashtab_map(&p->symtab[i].table, index_f[i], p);
		if (rc)
			goto out;
	}

	/*
	 * A sparse class value is absorbed by policydb_class_isvalid() and
	 * its siblings, but no such predicate exists for booleans: every
	 * user of bool_val_to_struct[] walks it by index and dereferences
	 * each entry -- cond_evaluate_expr(), the two getters and
	 * security_set_bools() -- so an unclaimed one has no consumer that
	 * can tolerate it.
	 */
	for (v = 0; v < p->p_bools.nprim; v++) {
		if (!p->bool_val_to_struct[v]) {
			pr_err("SELinux:  boolean %u is declared but not defined\n",
			       v + 1);
			rc = -EINVAL;
			goto out;
		}
	}

	if (p->mls_enabled) {
		rc = hashtab_map(&p->p_levels.table, sens_cat_index_check, p);
		if (rc)
			goto out;
	}

	rc = 0;
out:
	return rc;
}

/*
 * Free any memory allocated by a policy database structure.
 */
void policydb_destroy(struct policydb *p)
{
	struct ocontext *c, *ctmp;
	struct genfs *g, *gtmp;
	u32 i;
	struct role_allow *ra, *lra = NULL;

	for (i = 0; i < SYM_NUM; i++) {
		cond_resched();
		hashtab_map(&p->symtab[i].table, destroy_f[i], NULL);
		hashtab_destroy(&p->symtab[i].table);
	}

	for (i = 0; i < SYM_NUM; i++)
		kvfree(p->sym_val_to_name[i]);

	kfree(p->class_val_to_struct);
	kfree(p->role_val_to_struct);
	kfree(p->user_val_to_struct);
	kvfree(p->type_val_to_struct);

	avtab_destroy(&p->te_avtab);

	for (i = 0; i < OCON_NUM; i++) {
		cond_resched();
		c = p->ocontexts[i];
		while (c) {
			ctmp = c;
			c = c->next;
			ocontext_destroy(ctmp, i);
		}
		p->ocontexts[i] = NULL;
	}

	g = p->genfs;
	while (g) {
		cond_resched();
		kfree(g->fstype);
		c = g->head;
		while (c) {
			ctmp = c;
			c = c->next;
			ocontext_destroy(ctmp, OCON_FSUSE);
		}
		gtmp = g;
		g = g->next;
		kfree(gtmp);
	}
	p->genfs = NULL;

	cond_policydb_destroy(p);

	hashtab_map(&p->role_tr, role_tr_destroy, NULL);
	hashtab_destroy(&p->role_tr);

	for (ra = p->role_allow; ra; ra = ra->next) {
		cond_resched();
		kfree(lra);
		lra = ra;
	}
	kfree(lra);

	hashtab_map(&p->filename_trans, filenametr_destroy, NULL);
	hashtab_destroy(&p->filename_trans);

	hashtab_map(&p->range_tr, range_tr_destroy, NULL);
	hashtab_destroy(&p->range_tr);

	if (p->type_attr_map_array) {
		for (i = 0; i < p->p_types.nprim; i++)
			ebitmap_destroy(&p->type_attr_map_array[i]);
		kvfree(p->type_attr_map_array);
	}

	ebitmap_destroy(&p->filename_trans_ttypes);
	ebitmap_destroy(&p->policycaps);
	ebitmap_destroy(&p->permissive_map);
	ebitmap_destroy(&p->neveraudit_map);
}

/*
 * Load the initial SIDs specified in a policy database
 * structure into a SID table.
 */
int policydb_load_isids(struct policydb *p, struct sidtab *s)
{
	struct ocontext *head, *c;
	bool isid_init;
	int rc;

	rc = sidtab_init(s);
	if (rc) {
		pr_err("SELinux:  out of memory on SID table init\n");
		return rc;
	}

	isid_init = ebitmap_get_bit(&p->policycaps,
				    POLICYDB_CAP_USERSPACE_INITIAL_CONTEXT);

	head = p->ocontexts[OCON_ISID];
	for (c = head; c; c = c->next) {
		u32 sid = c->sid[0];
		const char *name = security_get_initial_sid_context(sid);

		if (sid == SECSID_NULL) {
			pr_err("SELinux:  SID 0 was assigned a context.\n");
			sidtab_destroy(s);
			return -EINVAL;
		}

		/* Ignore initial SIDs unused by this kernel. */
		if (!name)
			continue;

		/*
		 * Also ignore SECINITSID_INIT if the policy doesn't declare
		 * support for it
		 */
		if (sid == SECINITSID_INIT && !isid_init)
			continue;

		rc = sidtab_set_initial(s, sid, &c->context[0]);
		if (rc) {
			pr_err("SELinux:  unable to load initial SID %s.\n",
			       name);
			sidtab_destroy(s);
			return rc;
		}

		/*
		 * If the policy doesn't support the "userspace_initial_context"
		 * capability, set SECINITSID_INIT to the same context as
		 * SECINITSID_KERNEL. This ensures the same behavior as before
		 * the reintroduction of SECINITSID_INIT, where all tasks
		 * started before policy load would initially get the context
		 * corresponding to SECINITSID_KERNEL.
		 */
		if (sid == SECINITSID_KERNEL && !isid_init) {
			rc = sidtab_set_initial(s, SECINITSID_INIT,
						&c->context[0]);
			if (rc) {
				pr_err("SELinux:  unable to load initial SID %s.\n",
				       name);
				sidtab_destroy(s);
				return rc;
			}
		}
	}
	return 0;
}

bool policydb_class_isvalid(const struct policydb *p, u16 class)
{
	if (!class || class > p->p_classes.nprim)
		return false;
	if (!p->sym_val_to_name[SYM_CLASSES][class - 1])
		return false;
	return true;
}

bool policydb_user_isvalid(const struct policydb *p, u32 user)
{
	if (!user || user > p->p_users.nprim)
		return false;
	if (!p->sym_val_to_name[SYM_USERS][user - 1])
		return false;
	return true;
}

bool policydb_role_isvalid(const struct policydb *p, u32 role)
{
	if (!role || role > p->p_roles.nprim)
		return false;
	if (!p->sym_val_to_name[SYM_ROLES][role - 1])
		return false;
	return true;
}

bool policydb_type_isvalid(const struct policydb *p, u32 type)
{
	if (!type || type > p->p_types.nprim)
		return false;
	if (!p->sym_val_to_name[SYM_TYPES][type - 1])
		return false;
	return true;
}

bool policydb_simpletype_isvalid(const struct policydb *p, u32 type)
{
	const struct type_datum *datum;

	if (!type || type > p->p_types.nprim)
		return false;

	datum = p->type_val_to_struct[type - 1];
	if (!datum)
		return false;

	if (datum->attribute)
		return false;

	return true;
}

/*
 * Return true if the fields in the security context
 * structure `c' are valid.  Return 0 otherwise.
 */
bool policydb_context_isvalid(const struct policydb *p, const struct context *c)
{
	const struct role_datum *role;
	const struct user_datum *usrdatum;

	if (!c->role || c->role > p->p_roles.nprim)
		return false;

	if (!c->user || c->user > p->p_users.nprim)
		return false;

	if (!c->type || c->type > p->p_types.nprim)
		return false;

	if (c->role != OBJECT_R_VAL) {
		/*
		 * Role must be authorized for the type.
		 */
		role = p->role_val_to_struct[c->role - 1];
		if (!role || !ebitmap_get_bit(&role->types, c->type - 1))
			/* role may not be associated with type */
			return false;

		/*
		 * User must be authorized for the role.
		 */
		usrdatum = p->user_val_to_struct[c->user - 1];
		if (!usrdatum)
			return false;

		if (!ebitmap_get_bit(&usrdatum->roles, c->role - 1))
			/* user may not be associated with role */
			return false;
	}

	if (!mls_context_isvalid(p, c))
		return false;

	return true;
}

/*
 * Read a MLS range structure from a policydb binary
 * representation file.
 */
static int mls_read_range_helper(struct mls_range *r, struct policy_file *fp)
{
	__le32 buf[2];
	u32 items;
	int rc;

	rc = next_entry(buf, fp, sizeof(u32));
	if (rc)
		goto out;

	rc = -EINVAL;
	items = le32_to_cpu(buf[0]);
	if (items > ARRAY_SIZE(buf)) {
		pr_err("SELinux: mls:  range overflow\n");
		goto out;
	}

	rc = next_entry(buf, fp, sizeof(u32) * items);
	if (rc) {
		pr_err("SELinux: mls:  truncated range\n");
		goto out;
	}

	r->level[0].sens = le32_to_cpu(buf[0]);
	if (items > 1)
		r->level[1].sens = le32_to_cpu(buf[1]);
	else
		r->level[1].sens = r->level[0].sens;

	rc = ebitmap_read(&r->level[0].cat, fp);
	if (rc) {
		pr_err("SELinux: mls:  error reading low categories\n");
		goto out;
	}
	if (items > 1) {
		rc = ebitmap_read(&r->level[1].cat, fp);
		if (rc) {
			pr_err("SELinux: mls:  error reading high categories\n");
			goto bad_high;
		}
	} else {
		rc = ebitmap_cpy(&r->level[1].cat, &r->level[0].cat);
		if (rc) {
			pr_err("SELinux: mls:  out of memory\n");
			goto bad_high;
		}
	}

	return 0;
bad_high:
	ebitmap_destroy(&r->level[0].cat);
out:
	return rc;
}

/*
 * Read and validate a security context structure
 * from a policydb binary representation file.
 */
static int context_read_and_validate(struct context *c, struct policydb *p,
				     struct policy_file *fp)
{
	__le32 buf[3];
	int rc;

	rc = next_entry(buf, fp, sizeof buf);
	if (rc) {
		pr_err("SELinux: context truncated\n");
		goto out;
	}
	c->user = le32_to_cpu(buf[0]);
	c->role = le32_to_cpu(buf[1]);
	c->type = le32_to_cpu(buf[2]);
	if (p->policyvers >= POLICYDB_VERSION_MLS) {
		rc = mls_read_range_helper(&c->range, fp);
		if (rc) {
			pr_err("SELinux: error reading MLS range of context\n");
			goto out;
		}
	}

	rc = -EINVAL;
	if (!policydb_context_isvalid(p, c)) {
		pr_err("SELinux:  invalid security context\n");
		context_destroy(c);
		goto out;
	}
	rc = 0;
out:
	return rc;
}

/*
 * The following *_read functions are used to
 * read the symbol data from a policy database
 * binary representation file.
 */

int str_read(char **strp, gfp_t flags, struct policy_file *fp, u32 len)
{
	int rc;
	char *str;

	if ((len == 0) || (len == (u32)-1))
		return -EINVAL;

	if (size_check(sizeof(char), len, fp))
		return -EINVAL;

	str = kmalloc(len + 1, flags | __GFP_NOWARN);
	if (!str)
		return -ENOMEM;

	rc = next_entry(str, fp, len);
	if (rc) {
		kfree(str);
		return rc;
	}

	str[len] = '\0';
	*strp = str;
	return 0;
}

/*
 * Bitmap of the permission values a symtab has claimed.  Values are 1-based
 * and bounded by SEL_VEC_MAX, the width of an access vector, so the whole set
 * fits in a u32 and the callers reject an nprim past that width.
 */
static u32 perm_claimed_mask(u32 nprim)
{
	return nprim ? U32_MAX >> (SEL_VEC_MAX - nprim) : 0;
}

static int perm_read(struct policydb *p, struct symtab *s,
		     struct policy_file *fp, u32 *claimed)
{
	char *key = NULL;
	struct perm_datum *perdatum;
	int rc;
	__le32 buf[2];
	u32 len;

	perdatum = kzalloc_obj(*perdatum);
	if (!perdatum)
		return -ENOMEM;

	rc = next_entry(buf, fp, sizeof buf);
	if (rc)
		goto bad;

	len = le32_to_cpu(buf[0]);
	perdatum->value = le32_to_cpu(buf[1]);
	rc = -EINVAL;
	if (perdatum->value < 1 || perdatum->value > SEL_VEC_MAX)
		goto bad;
	/* indexes an nprim-sized array in security_get_permissions() */
	if (perdatum->value > s->nprim)
		goto bad;
	/* two permissions cannot share one slot of that array */
	if (*claimed & (1U << (perdatum->value - 1)))
		goto bad;
	*claimed |= 1U << (perdatum->value - 1);

	rc = str_read(&key, GFP_KERNEL, fp, len);
	if (rc)
		goto bad;

	rc = symtab_insert(s, key, perdatum);
	if (rc)
		goto bad;

	return 0;
bad:
	perm_destroy(key, perdatum, NULL);
	return rc;
}

static int common_read(struct policydb *p, struct symtab *s, struct policy_file *fp)
{
	char *key = NULL;
	struct common_datum *comdatum;
	__le32 buf[4];
	u32 i, len, nel, claimed = 0;
	int rc;

	comdatum = kzalloc_obj(*comdatum);
	if (!comdatum)
		return -ENOMEM;

	rc = next_entry(buf, fp, sizeof buf);
	if (rc)
		goto bad;

	len = le32_to_cpu(buf[0]);
	comdatum->value = le32_to_cpu(buf[1]);
	nel = le32_to_cpu(buf[3]);
	rc = -EINVAL;
	if (nel > SEL_VEC_MAX)
		goto bad;

	/* perm_read() reads at least 64 bytes for any valid permission */
	rc = size_check(2 * sizeof(u32), nel, fp);
	if (rc)
		goto bad;

	rc = symtab_init(&comdatum->permissions, nel);
	if (rc)
		goto bad;
	comdatum->permissions.nprim = le32_to_cpu(buf[2]);
	/* no permission value can reach a slot past SEL_VEC_MAX */
	rc = -EINVAL;
	if (comdatum->permissions.nprim > SEL_VEC_MAX)
		goto bad;

	rc = str_read(&key, GFP_KERNEL, fp, len);
	if (rc)
		goto bad;

	for (i = 0; i < nel; i++) {
		rc = perm_read(p, &comdatum->permissions, fp, &claimed);
		if (rc)
			goto bad;
	}

	rc = -EINVAL;
	if (claimed != perm_claimed_mask(comdatum->permissions.nprim)) {
		pr_err("SELinux:  common %s does not define every permission it declares\n",
		       key);
		goto bad;
	}

	hash_eval(&comdatum->permissions.table, "common_permissions", key);

	rc = symtab_insert(s, key, comdatum);
	if (rc)
		goto bad;
	return 0;
bad:
	common_destroy(key, comdatum, NULL);
	return rc;
}

static void type_set_init(struct type_set *t)
{
	ebitmap_init(&t->types);
	ebitmap_init(&t->negset);
}

static int type_set_read(struct type_set *t, struct policy_file *fp)
{
	__le32 buf[1];
	int rc;

	if (ebitmap_read(&t->types, fp))
		return -EINVAL;
	if (ebitmap_read(&t->negset, fp))
		return -EINVAL;

	rc = next_entry(buf, fp, sizeof(u32));
	if (rc < 0)
		return -EINVAL;
	t->flags = le32_to_cpu(buf[0]);

	return 0;
}

static int read_cons_helper(struct policydb *p, struct constraint_node **nodep,
			    u32 ncons, int allowxtarget, struct policy_file *fp)
{
	struct constraint_node *c, *lc;
	struct constraint_expr *e, *le;
	__le32 buf[3];
	u32 i, j, nexpr;
	int rc, depth;

	lc = NULL;
	for (i = 0; i < ncons; i++) {
		c = kzalloc_obj(*c);
		if (!c)
			return -ENOMEM;

		if (lc)
			lc->next = c;
		else
			*nodep = c;

		rc = next_entry(buf, fp, (sizeof(u32) * 2));
		if (rc)
			return rc;
		c->permissions = le32_to_cpu(buf[0]);
		nexpr = le32_to_cpu(buf[1]);
		le = NULL;
		depth = -1;
		for (j = 0; j < nexpr; j++) {
			e = kzalloc_obj(*e);
			if (!e)
				return -ENOMEM;

			if (le)
				le->next = e;
			else
				c->expr = e;

			rc = next_entry(buf, fp, (sizeof(u32) * 3));
			if (rc)
				return rc;
			e->expr_type = le32_to_cpu(buf[0]);
			e->attr = le32_to_cpu(buf[1]);
			e->op = le32_to_cpu(buf[2]);

			switch (e->expr_type) {
			case CEXPR_NOT:
				if (depth < 0)
					return -EINVAL;
				break;
			case CEXPR_AND:
			case CEXPR_OR:
				if (depth < 1)
					return -EINVAL;
				depth--;
				break;
			case CEXPR_ATTR:
				if (depth == (CEXPR_MAXDEPTH - 1))
					return -EINVAL;
				depth++;
				break;
			case CEXPR_NAMES:
				if (!allowxtarget && (e->attr & CEXPR_XTARGET))
					return -EINVAL;
				if (depth == (CEXPR_MAXDEPTH - 1))
					return -EINVAL;
				depth++;
				rc = ebitmap_read(&e->names, fp);
				if (rc)
					return rc;
				if (p->policyvers >=
				    POLICYDB_VERSION_CONSTRAINT_NAMES) {
					e->type_names = kzalloc_obj(*e->type_names);
					if (!e->type_names)
						return -ENOMEM;
					type_set_init(e->type_names);
					rc = type_set_read(e->type_names, fp);
					if (rc)
						return rc;
				}
				break;
			default:
				return -EINVAL;
			}
			le = e;
		}
		if (depth != 0)
			return -EINVAL;
		lc = c;
	}

	return 0;
}

static int class_read(struct policydb *p, struct symtab *s, struct policy_file *fp)
{
	char *key = NULL;
	struct class_datum *cladatum;
	__le32 buf[6];
	u32 i, len, len2, ncons, nel, val, claimed = 0, inherited = 0;
	int rc;

	cladatum = kzalloc_obj(*cladatum);
	if (!cladatum)
		return -ENOMEM;

	rc = next_entry(buf, fp, sizeof(u32) * 6);
	if (rc)
		goto bad;

	len = le32_to_cpu(buf[0]);
	len2 = le32_to_cpu(buf[1]);
	nel = le32_to_cpu(buf[4]);
	rc = -EINVAL;
	if (nel > SEL_VEC_MAX)
		goto bad;

	val = le32_to_cpu(buf[2]);
	rc = -EINVAL;
	if (val > U16_MAX)
		goto bad;
	cladatum->value = val;

	/* perm_read() reads at least 64 bytes for any valid permission */
	rc = size_check(2 * sizeof(u32), nel, fp);
	if (rc)
		goto bad;

	rc = symtab_init(&cladatum->permissions, nel);
	if (rc)
		goto bad;
	cladatum->permissions.nprim = le32_to_cpu(buf[3]);
	/* no permission value can reach a slot past SEL_VEC_MAX */
	rc = -EINVAL;
	if (cladatum->permissions.nprim > SEL_VEC_MAX)
		goto bad;

	ncons = le32_to_cpu(buf[5]);

	rc = str_read(&key, GFP_KERNEL, fp, len);
	if (rc)
		goto bad;

	if (len2) {
		rc = str_read(&cladatum->comkey, GFP_KERNEL, fp, len2);
		if (rc)
			goto bad;

		rc = -EINVAL;
		cladatum->comdatum =
			symtab_search(&p->p_commons, cladatum->comkey);
		if (!cladatum->comdatum) {
			pr_err("SELinux:  unknown common %s\n",
			       cladatum->comkey);
			goto bad;
		}

		/*
		 * security_get_permissions() maps the common's permissions
		 * into an array sized by this class's nprim, so a class must
		 * declare at least as many as the common it inherits.
		 */
		if (cladatum->permissions.nprim <
		    cladatum->comdatum->permissions.nprim) {
			pr_err("SELinux:  class %s has fewer permissions than common %s\n",
			       key, cladatum->comkey);
			goto bad;
		}
	}
	for (i = 0; i < nel; i++) {
		rc = perm_read(p, &cladatum->permissions, fp, &claimed);
		if (rc)
			goto bad;
	}

	/* the class's own permissions must claim the slots the common leaves */
	if (cladatum->comdatum)
		inherited = cladatum->comdatum->permissions.nprim;
	rc = -EINVAL;
	if (claimed != (perm_claimed_mask(cladatum->permissions.nprim) &
			~perm_claimed_mask(inherited))) {
		pr_err("SELinux:  class %s does not define every permission it declares\n",
		       key);
		goto bad;
	}

	hash_eval(&cladatum->permissions.table, "class_permissions", key);

	rc = read_cons_helper(p, &cladatum->constraints, ncons, 0, fp);
	if (rc)
		goto bad;

	if (p->policyvers >= POLICYDB_VERSION_VALIDATETRANS) {
		/* grab the validatetrans rules */
		rc = next_entry(buf, fp, sizeof(u32));
		if (rc)
			goto bad;
		ncons = le32_to_cpu(buf[0]);
		rc = read_cons_helper(p, &cladatum->validatetrans, ncons, 1,
				      fp);
		if (rc)
			goto bad;
	}

	if (p->policyvers >= POLICYDB_VERSION_NEW_OBJECT_DEFAULTS) {
		rc = next_entry(buf, fp, sizeof(u32) * 3);
		if (rc)
			goto bad;

		rc = -EINVAL;
		val = le32_to_cpu(buf[0]);
		switch (val) {
		case 0:
		case DEFAULT_SOURCE:
		case DEFAULT_TARGET:
			cladatum->default_user = val;
			break;
		default:
			goto bad;
		}
		val = le32_to_cpu(buf[1]);
		switch (val) {
		case 0:
		case DEFAULT_SOURCE:
		case DEFAULT_TARGET:
			cladatum->default_role = val;
			break;
		default:
			goto bad;
		}
		val = le32_to_cpu(buf[2]);
		switch (val) {
		case 0:
		case DEFAULT_SOURCE_LOW:
		case DEFAULT_SOURCE_HIGH:
		case DEFAULT_SOURCE_LOW_HIGH:
		case DEFAULT_TARGET_LOW:
		case DEFAULT_TARGET_HIGH:
		case DEFAULT_TARGET_LOW_HIGH:
		case DEFAULT_GLBLUB:
			cladatum->default_range = val;
			break;
		default:
			goto bad;
		}
	}

	if (p->policyvers >= POLICYDB_VERSION_DEFAULT_TYPE) {
		rc = next_entry(buf, fp, sizeof(u32) * 1);
		if (rc)
			goto bad;
		rc = -EINVAL;
		val = le32_to_cpu(buf[0]);
		switch (val) {
		case 0:
		case DEFAULT_TARGET:
		case DEFAULT_SOURCE:
			cladatum->default_type = val;
			break;
		default:
			goto bad;
		}
	}

	rc = symtab_insert(s, key, cladatum);
	if (rc)
		goto bad;

	return 0;
bad:
	cls_destroy(key, cladatum, NULL);
	if (rc)
		pr_err("SELinux:  invalid class\n");
	return rc;
}

static int role_read(struct policydb *p, struct symtab *s, struct policy_file *fp)
{
	char *key = NULL;
	struct role_datum *role;
	int rc;
	unsigned int to_read = 2;
	__le32 buf[3];
	u32 len;

	role = kzalloc_obj(*role);
	if (!role)
		return -ENOMEM;

	if (p->policyvers >= POLICYDB_VERSION_BOUNDARY)
		to_read = 3;

	rc = next_entry(buf, fp, sizeof(buf[0]) * to_read);
	if (rc)
		goto bad;

	len = le32_to_cpu(buf[0]);
	role->value = le32_to_cpu(buf[1]);
	if (p->policyvers >= POLICYDB_VERSION_BOUNDARY)
		role->bounds = le32_to_cpu(buf[2]);

	rc = str_read(&key, GFP_KERNEL, fp, len);
	if (rc)
		goto bad;

	rc = ebitmap_read(&role->dominates, fp);
	if (rc)
		goto bad;

	rc = ebitmap_read(&role->types, fp);
	if (rc)
		goto bad;

	if (strcmp(key, OBJECT_R) == 0) {
		rc = -EINVAL;
		if (role->value != OBJECT_R_VAL) {
			pr_err("SELinux: Role %s has wrong value %d\n",
			       OBJECT_R, role->value);
			goto bad;
		}
		rc = 0;
		goto bad;
	}

	rc = symtab_insert(s, key, role);
	if (rc)
		goto bad;
	return 0;
bad:
	role_destroy(key, role, NULL);
	return rc;
}

static int type_read(struct policydb *p, struct symtab *s, struct policy_file *fp)
{
	char *key = NULL;
	struct type_datum *typdatum;
	int rc;
	unsigned int to_read = 3;
	__le32 buf[4];
	u32 len;

	typdatum = kzalloc_obj(*typdatum);
	if (!typdatum)
		return -ENOMEM;

	if (p->policyvers >= POLICYDB_VERSION_BOUNDARY)
		to_read = 4;

	rc = next_entry(buf, fp, sizeof(buf[0]) * to_read);
	if (rc)
		goto bad;

	len = le32_to_cpu(buf[0]);
	typdatum->value = le32_to_cpu(buf[1]);
	if (p->policyvers >= POLICYDB_VERSION_BOUNDARY) {
		u32 prop = le32_to_cpu(buf[2]);

		if (prop & TYPEDATUM_PROPERTY_PRIMARY)
			typdatum->primary = 1;
		if (prop & TYPEDATUM_PROPERTY_ATTRIBUTE)
			typdatum->attribute = 1;

		typdatum->bounds = le32_to_cpu(buf[3]);
	} else {
		typdatum->primary = le32_to_cpu(buf[2]);
	}

	rc = str_read(&key, GFP_KERNEL, fp, len);
	if (rc)
		goto bad;

	rc = symtab_insert(s, key, typdatum);
	if (rc)
		goto bad;
	return 0;
bad:
	type_destroy(key, typdatum, NULL);
	return rc;
}

/*
 * Read a MLS level structure from a policydb binary
 * representation file.
 */
static int mls_read_level(struct mls_level *lp, struct policy_file *fp)
{
	__le32 buf[1];
	int rc;

	memset(lp, 0, sizeof(*lp));

	rc = next_entry(buf, fp, sizeof buf);
	if (rc) {
		pr_err("SELinux: mls: truncated level\n");
		return rc;
	}
	lp->sens = le32_to_cpu(buf[0]);

	rc = ebitmap_read(&lp->cat, fp);
	if (rc) {
		pr_err("SELinux: mls:  error reading level categories\n");
		return rc;
	}
	return 0;
}

static int user_read(struct policydb *p, struct symtab *s, struct policy_file *fp)
{
	char *key = NULL;
	struct user_datum *usrdatum;
	int rc;
	unsigned int to_read = 2;
	__le32 buf[3];
	u32 len;

	usrdatum = kzalloc_obj(*usrdatum);
	if (!usrdatum)
		return -ENOMEM;

	if (p->policyvers >= POLICYDB_VERSION_BOUNDARY)
		to_read = 3;

	rc = next_entry(buf, fp, sizeof(buf[0]) * to_read);
	if (rc)
		goto bad;

	len = le32_to_cpu(buf[0]);
	usrdatum->value = le32_to_cpu(buf[1]);
	if (p->policyvers >= POLICYDB_VERSION_BOUNDARY)
		usrdatum->bounds = le32_to_cpu(buf[2]);

	rc = str_read(&key, GFP_KERNEL, fp, len);
	if (rc)
		goto bad;

	rc = ebitmap_read(&usrdatum->roles, fp);
	if (rc)
		goto bad;

	if (p->policyvers >= POLICYDB_VERSION_MLS) {
		rc = mls_read_range_helper(&usrdatum->range, fp);
		if (rc)
			goto bad;
		rc = mls_read_level(&usrdatum->dfltlevel, fp);
		if (rc)
			goto bad;
	}

	rc = symtab_insert(s, key, usrdatum);
	if (rc)
		goto bad;
	return 0;
bad:
	user_destroy(key, usrdatum, NULL);
	return rc;
}

static int sens_read(struct policydb *p, struct symtab *s, struct policy_file *fp)
{
	char *key = NULL;
	struct level_datum *levdatum;
	int rc;
	__le32 buf[2];
	u32 len, val;

	levdatum = kzalloc_obj(*levdatum);
	if (!levdatum)
		return -ENOMEM;

	rc = next_entry(buf, fp, sizeof buf);
	if (rc)
		goto bad;

	len = le32_to_cpu(buf[0]);
	val = le32_to_cpu(buf[1]);
	rc = -EINVAL;
	if (!val_is_boolean(val))
		goto bad;
	levdatum->isalias = val;

	rc = str_read(&key, GFP_KERNEL, fp, len);
	if (rc)
		goto bad;

	rc = mls_read_level(&levdatum->level, fp);
	if (rc)
		goto bad;

	rc = symtab_insert(s, key, levdatum);
	if (rc)
		goto bad;
	return 0;
bad:
	sens_destroy(key, levdatum, NULL);
	if (rc)
		pr_err("SELinux:  invalid sensitivity\n");
	return rc;
}

static int cat_read(struct policydb *p, struct symtab *s, struct policy_file *fp)
{
	char *key = NULL;
	struct cat_datum *catdatum;
	int rc;
	__le32 buf[3];
	u32 len, val;

	catdatum = kzalloc_obj(*catdatum);
	if (!catdatum)
		return -ENOMEM;

	rc = next_entry(buf, fp, sizeof buf);
	if (rc)
		goto bad;

	len = le32_to_cpu(buf[0]);
	catdatum->value = le32_to_cpu(buf[1]);
	val = le32_to_cpu(buf[2]);
	rc = -EINVAL;
	if (!val_is_boolean(val))
		goto bad;
	catdatum->isalias = val;

	rc = str_read(&key, GFP_KERNEL, fp, len);
	if (rc)
		goto bad;

	rc = symtab_insert(s, key, catdatum);
	if (rc)
		goto bad;
	return 0;
bad:
	cat_destroy(key, catdatum, NULL);
	if (rc)
		pr_err("SELinux:  invalid category\n");
	return rc;
}

/* clang-format off */
static int (*const read_f[SYM_NUM])(struct policydb *p, struct symtab *s,
				    struct policy_file *fp) = {
	common_read,
	class_read,
	role_read,
	type_read,
	user_read,
	cond_read_bool,
	sens_read,
	cat_read,
};
/* clang-format on */

static int user_bounds_sanity_check(void *key, void *datum, void *datap)
{
	struct user_datum *upper, *user;
	struct policydb *p = datap;
	int depth = 0;

	upper = user = datum;
	while (upper->bounds) {
		struct ebitmap_node *node;
		u32 bit;

		if (++depth == POLICYDB_BOUNDS_MAXDEPTH) {
			pr_err("SELinux: user %s: "
			       "too deep or looped boundary\n",
			       (char *)key);
			return -EINVAL;
		}

		if (!policydb_user_isvalid(p, upper->bounds)) {
			pr_err("SELinux: user %s: invalid boundary id %d\n",
			       (char *) key, upper->bounds);
			return -EINVAL;
		}

		upper = p->user_val_to_struct[upper->bounds - 1];
		ebitmap_for_each_positive_bit(&user->roles, node, bit)
		{
			if (ebitmap_get_bit(&upper->roles, bit))
				continue;

			pr_err("SELinux: boundary violated policy: "
			       "user=%s role=%s bounds=%s\n",
			       sym_name(p, SYM_USERS, user->value - 1),
			       sym_name(p, SYM_ROLES, bit),
			       sym_name(p, SYM_USERS, upper->value - 1));

			return -EINVAL;
		}
	}

	return 0;
}

static int role_bounds_sanity_check(void *key, void *datum, void *datap)
{
	struct role_datum *upper, *role;
	struct policydb *p = datap;
	int depth = 0;

	upper = role = datum;
	while (upper->bounds) {
		struct ebitmap_node *node;
		u32 bit;

		if (++depth == POLICYDB_BOUNDS_MAXDEPTH) {
			pr_err("SELinux: role %s: "
			       "too deep or looped bounds\n",
			       (char *)key);
			return -EINVAL;
		}

		if (!policydb_role_isvalid(p, upper->bounds)) {
			pr_err("SELinux: role %s: invalid boundary id %d\n",
			       (char *) key, upper->bounds);
			return -EINVAL;
		}

		upper = p->role_val_to_struct[upper->bounds - 1];
		ebitmap_for_each_positive_bit(&role->types, node, bit)
		{
			if (ebitmap_get_bit(&upper->types, bit))
				continue;

			pr_err("SELinux: boundary violated policy: "
			       "role=%s type=%s bounds=%s\n",
			       sym_name(p, SYM_ROLES, role->value - 1),
			       sym_name(p, SYM_TYPES, bit),
			       sym_name(p, SYM_ROLES, upper->value - 1));

			return -EINVAL;
		}
	}

	return 0;
}

static int type_bounds_sanity_check(void *key, void *datum, void *datap)
{
	struct type_datum *upper;
	struct policydb *p = datap;
	int depth = 0;

	upper = datum;
	while (upper->bounds) {
		if (++depth == POLICYDB_BOUNDS_MAXDEPTH) {
			pr_err("SELinux: type %s: "
			       "too deep or looped boundary\n",
			       (char *)key);
			return -EINVAL;
		}

		if (!policydb_type_isvalid(p, upper->bounds)) {
			pr_err("SELinux: type %s: invalid boundary id %d\n",
			       (char *) key, upper->bounds);
			return -EINVAL;
		}

		upper = p->type_val_to_struct[upper->bounds - 1];
		if (upper->attribute) {
			pr_err("SELinux: type %s: "
			       "bounded by attribute %s\n",
			       (char *)key,
			       sym_name(p, SYM_TYPES, upper->value - 1));
			return -EINVAL;
		}
	}

	return 0;
}

static int policydb_bounds_sanity_check(struct policydb *p)
{
	int rc;

	if (p->policyvers < POLICYDB_VERSION_BOUNDARY)
		return 0;

	rc = hashtab_map(&p->p_users.table, user_bounds_sanity_check, p);
	if (rc)
		return rc;

	rc = hashtab_map(&p->p_roles.table, role_bounds_sanity_check, p);
	if (rc)
		return rc;

	rc = hashtab_map(&p->p_types.table, type_bounds_sanity_check, p);
	if (rc)
		return rc;

	return 0;
}

u16 string_to_security_class(struct policydb *p, const char *name)
{
	struct class_datum *cladatum;

	cladatum = symtab_search(&p->p_classes, name);
	if (!cladatum)
		return 0;

	return cladatum->value;
}

u32 string_to_av_perm(struct policydb *p, u16 tclass, const char *name)
{
	struct class_datum *cladatum;
	struct perm_datum *perdatum = NULL;
	struct common_datum *comdatum;

	if (!tclass || tclass > p->p_classes.nprim)
		return 0;

	cladatum = p->class_val_to_struct[tclass - 1];
	comdatum = cladatum->comdatum;
	if (comdatum)
		perdatum = symtab_search(&comdatum->permissions, name);
	if (!perdatum)
		perdatum = symtab_search(&cladatum->permissions, name);
	if (!perdatum)
		return 0;

	return 1U << (perdatum->value - 1);
}

static int range_read(struct policydb *p, struct policy_file *fp)
{
	struct range_trans *rt = NULL;
	struct mls_range *r = NULL;
	int rc;
	__le32 buf[2];
	u32 i, nel, val;

	if (p->policyvers < POLICYDB_VERSION_MLS)
		return 0;

	rc = next_entry(buf, fp, sizeof(u32));
	if (rc)
		return rc;

	nel = le32_to_cpu(buf[0]);

	/* we read at least 64 bytes and mls_read_range_helper() 32 bytes
	 * for any valid range-transition
	 */
	rc = size_check(3 * sizeof(u32), nel, fp);
	if (rc)
		return rc;

	rc = hashtab_init(&p->range_tr, nel);
	if (rc)
		return rc;

	for (i = 0; i < nel; i++) {
		rc = -ENOMEM;
		rt = kzalloc_obj(*rt);
		if (!rt)
			goto out;

		rc = next_entry(buf, fp, (sizeof(u32) * 2));
		if (rc)
			goto out;

		rt->source_type = le32_to_cpu(buf[0]);
		rt->target_type = le32_to_cpu(buf[1]);
		if (p->policyvers >= POLICYDB_VERSION_RANGETRANS) {
			rc = next_entry(buf, fp, sizeof(u32));
			if (rc)
				goto out;
			rc = -EINVAL;
			val = le32_to_cpu(buf[0]);
			if (val > U16_MAX)
				goto out;
			rt->target_class = val;
		} else
			rt->target_class = p->process_class;

		rc = -EINVAL;
		if (!policydb_type_isvalid(p, rt->source_type) ||
		    !policydb_type_isvalid(p, rt->target_type) ||
		    !policydb_class_isvalid(p, rt->target_class))
			goto out;

		rc = -ENOMEM;
		r = kzalloc_obj(*r);
		if (!r)
			goto out;

		rc = mls_read_range_helper(r, fp);
		if (rc)
			goto out;

		rc = -EINVAL;
		if (!mls_range_isvalid(p, r)) {
			pr_warn("SELinux:  rangetrans:  invalid range\n");
			goto out;
		}

		rc = hashtab_insert(&p->range_tr, rt, r, rangetr_key_params);
		if (rc)
			goto out;

		rt = NULL;
		r = NULL;
	}
	hash_eval(&p->range_tr, "rangetr", NULL);
	rc = 0;
out:
	kfree(rt);
	kfree(r);
	if (rc)
		pr_err("SELinux:  invalid range\n");
	return rc;
}

static int filename_trans_read_helper_compat(struct policydb *p, struct policy_file *fp)
{
	struct filename_trans_key key, *ft = NULL;
	struct filename_trans_datum *last, *datum = NULL;
	char *name = NULL;
	u32 len, stype, otype, val;
	__le32 buf[4];
	int rc;

	/* length of the path component string */
	rc = next_entry(buf, fp, sizeof(u32));
	if (rc)
		return rc;
	len = le32_to_cpu(buf[0]);

	/* path component string */
	rc = str_read(&name, GFP_KERNEL, fp, len);
	if (rc)
		return rc;

	rc = next_entry(buf, fp, sizeof(u32) * 4);
	if (rc)
		goto out;

	rc = -EINVAL;
	stype = le32_to_cpu(buf[0]);
	if (!policydb_type_isvalid(p, stype))
		goto out;
	key.ttype = le32_to_cpu(buf[1]);
	if (!policydb_type_isvalid(p, key.ttype))
		goto out;
	val = le32_to_cpu(buf[2]);
	if (val > U16_MAX || !policydb_class_isvalid(p, val))
		goto out;
	key.tclass = val;
	key.name = name;

	otype = le32_to_cpu(buf[3]);
	if (!policydb_simpletype_isvalid(p, otype))
		goto out;

	last = NULL;
	datum = policydb_filenametr_search(p, &key);
	while (datum) {
		if (unlikely(ebitmap_get_bit(&datum->stypes, stype - 1))) {
			/* conflicting/duplicate rules are ignored */
			datum = NULL;
			rc = 0;
			goto out;
		}
		if (likely(datum->otype == otype))
			break;
		last = datum;
		datum = datum->next;
	}
	if (!datum) {
		rc = -ENOMEM;
		datum = kmalloc_obj(*datum);
		if (!datum)
			goto out;

		ebitmap_init(&datum->stypes);
		datum->otype = otype;
		datum->next = NULL;

		if (unlikely(last)) {
			last->next = datum;
		} else {
			rc = -ENOMEM;
			ft = kmemdup(&key, sizeof(key), GFP_KERNEL);
			if (!ft)
				goto out;

			rc = hashtab_insert(&p->filename_trans, ft, datum,
					    filenametr_key_params);
			if (rc)
				goto out;
			name = NULL;

			rc = ebitmap_set_bit(&p->filename_trans_ttypes,
					     key.ttype, 1);
			if (rc)
				return rc;
		}
	}
	kfree(name);
	return ebitmap_set_bit(&datum->stypes, stype - 1, 1);

out:
	kfree(ft);
	kfree(name);
	kfree(datum);

	if (rc)
		pr_err("SELinux:  invalid compat filename transition\n");
	return rc;
}

static int filename_trans_read_helper(struct policydb *p, struct policy_file *fp)
{
	struct filename_trans_key *ft = NULL;
	struct filename_trans_datum **dst, *datum, *first = NULL;
	char *name = NULL;
	u32 len, ttype, ndatum, i, val;
	u16 tclass;
	__le32 buf[3];
	int rc;

	/* length of the path component string */
	rc = next_entry(buf, fp, sizeof(u32));
	if (rc)
		return rc;
	len = le32_to_cpu(buf[0]);

	/* path component string */
	rc = str_read(&name, GFP_KERNEL, fp, len);
	if (rc)
		return rc;

	rc = next_entry(buf, fp, sizeof(u32) * 3);
	if (rc)
		goto out;

	rc = -EINVAL;
	ttype = le32_to_cpu(buf[0]);
	if (!policydb_type_isvalid(p, ttype))
		goto out;
	val = le32_to_cpu(buf[1]);
	rc = -EINVAL;
	if (val > U16_MAX || !policydb_class_isvalid(p, val))
		goto out;
	tclass = val;

	ndatum = le32_to_cpu(buf[2]);
	if (ndatum == 0) {
		pr_err("SELinux:  Filename transition key with no datum\n");
		rc = -ENOENT;
		goto out;
	}

	dst = &first;
	for (i = 0; i < ndatum; i++) {
		rc = -ENOMEM;
		datum = kmalloc_obj(*datum);
		if (!datum)
			goto out;

		datum->next = NULL;
		*dst = datum;

		/* ebitmap_read() will at least init the bitmap */
		rc = ebitmap_read(&datum->stypes, fp);
		if (rc)
			goto out;

		rc = next_entry(buf, fp, sizeof(u32));
		if (rc)
			goto out;

		datum->otype = le32_to_cpu(buf[0]);

		rc = -EINVAL;
		if (!policydb_simpletype_isvalid(p, datum->otype))
			goto out;

		dst = &datum->next;
	}

	rc = -ENOMEM;
	ft = kmalloc_obj(*ft);
	if (!ft)
		goto out;

	ft->ttype = ttype;
	ft->tclass = tclass;
	ft->name = name;

	rc = hashtab_insert(&p->filename_trans, ft, first,
			    filenametr_key_params);
	if (rc == -EEXIST)
		pr_err("SELinux:  Duplicate filename transition key\n");
	if (rc)
		goto out;

	return ebitmap_set_bit(&p->filename_trans_ttypes, ttype, 1);

out:
	kfree(ft);
	kfree(name);
	while (first) {
		datum = first;
		first = first->next;

		ebitmap_destroy(&datum->stypes);
		kfree(datum);
	}

	if (rc)
		pr_err("SELinux:  invalid filename transition\n");
	return rc;
}

static int filename_trans_read(struct policydb *p, struct policy_file *fp)
{
	u32 nel, i;
	__le32 buf[1];
	int rc;

	if (p->policyvers < POLICYDB_VERSION_FILENAME_TRANS)
		return 0;

	rc = next_entry(buf, fp, sizeof(u32));
	if (rc)
		return rc;
	nel = le32_to_cpu(buf[0]);

	if (p->policyvers < POLICYDB_VERSION_COMP_FTRANS) {
		p->compat_filename_trans_count = nel;

		rc = hashtab_init(&p->filename_trans, (1 << 11));
		if (rc)
			return rc;

		for (i = 0; i < nel; i++) {
			rc = filename_trans_read_helper_compat(p, fp);
			if (rc)
				return rc;
		}
	} else {
		rc = hashtab_init(&p->filename_trans, nel);
		if (rc)
			return rc;

		for (i = 0; i < nel; i++) {
			rc = filename_trans_read_helper(p, fp);
			if (rc)
				return rc;
		}
	}
	hash_eval(&p->filename_trans, "filenametr", NULL);
	return 0;
}

static int genfs_read(struct policydb *p, struct policy_file *fp)
{
	int rc;
	u32 i, j, nel, nel2, len, len2, val;
	__le32 buf[1];
	struct ocontext *l, *c;
	struct ocontext *newc = NULL;
	struct genfs *genfs_p, *genfs;
	struct genfs *newgenfs = NULL;

	rc = next_entry(buf, fp, sizeof(u32));
	if (rc)
		return rc;
	nel = le32_to_cpu(buf[0]);

	for (i = 0; i < nel; i++) {
		rc = next_entry(buf, fp, sizeof(u32));
		if (rc)
			goto out;
		len = le32_to_cpu(buf[0]);

		rc = -ENOMEM;
		newgenfs = kzalloc_obj(*newgenfs);
		if (!newgenfs)
			goto out;

		rc = str_read(&newgenfs->fstype, GFP_KERNEL, fp, len);
		if (rc)
			goto out;

		for (genfs_p = NULL, genfs = p->genfs; genfs;
		     genfs_p = genfs, genfs = genfs->next) {
			rc = -EINVAL;
			if (strcmp(newgenfs->fstype, genfs->fstype) == 0) {
				pr_err("SELinux:  dup genfs fstype %s\n",
				       newgenfs->fstype);
				goto out;
			}
			if (strcmp(newgenfs->fstype, genfs->fstype) < 0)
				break;
		}
		newgenfs->next = genfs;
		if (genfs_p)
			genfs_p->next = newgenfs;
		else
			p->genfs = newgenfs;
		genfs = newgenfs;
		newgenfs = NULL;

		rc = next_entry(buf, fp, sizeof(u32));
		if (rc)
			goto out;

		nel2 = le32_to_cpu(buf[0]);
		for (j = 0; j < nel2; j++) {
			rc = next_entry(buf, fp, sizeof(u32));
			if (rc)
				goto out;
			len = le32_to_cpu(buf[0]);

			rc = -ENOMEM;
			newc = kzalloc_obj(*newc);
			if (!newc)
				goto out;

			rc = str_read(&newc->u.name, GFP_KERNEL, fp, len);
			if (rc)
				goto out;

			rc = next_entry(buf, fp, sizeof(u32));
			if (rc)
				goto out;

			rc = -EINVAL;
			val = le32_to_cpu(buf[0]);
			if (val > U16_MAX || (val != 0 && !policydb_class_isvalid(p, val)))
				goto out;
			newc->v.sclass = val;
			rc = context_read_and_validate(&newc->context[0], p,
						       fp);
			if (rc)
				goto out;

			for (l = NULL, c = genfs->head; c; l = c, c = c->next) {
				rc = -EINVAL;
				if (!strcmp(newc->u.name, c->u.name) &&
				    (!c->v.sclass || !newc->v.sclass ||
				     newc->v.sclass == c->v.sclass)) {
					pr_err("SELinux:  dup genfs entry (%s,%s)\n",
					       genfs->fstype, c->u.name);
					goto out;
				}
				len = strlen(newc->u.name);
				len2 = strlen(c->u.name);
				if (len > len2)
					break;
			}

			newc->next = c;
			if (l)
				l->next = newc;
			else
				genfs->head = newc;
			newc = NULL;
		}
	}
	rc = 0;
out:
	if (newgenfs) {
		kfree(newgenfs->fstype);
		kfree(newgenfs);
	}
	ocontext_destroy(newc, OCON_FSUSE);

	if (rc)
		pr_err("SELinux:  invalid genfs\n");

	return rc;
}

static int ocontext_read(struct policydb *p,
			 const struct policydb_compat_info *info, struct policy_file *fp)
{
	int rc;
	unsigned int i;
	u32 j, nel, len, val;
	__be64 prefixbuf[1];
	__le32 buf[3];
	struct ocontext *l, *c;
	u32 nodebuf[8];

	for (i = 0; i < info->ocon_num; i++) {
		rc = next_entry(buf, fp, sizeof(u32));
		if (rc)
			goto out;
		nel = le32_to_cpu(buf[0]);

		l = NULL;
		for (j = 0; j < nel; j++) {
			rc = -ENOMEM;
			c = kzalloc_obj(*c);
			if (!c)
				goto out;
			if (l)
				l->next = c;
			else
				p->ocontexts[i] = c;
			l = c;

			switch (i) {
			case OCON_ISID:
				rc = next_entry(buf, fp, sizeof(u32));
				if (rc)
					goto out;

				c->sid[0] = le32_to_cpu(buf[0]);
				rc = context_read_and_validate(&c->context[0],
							       p, fp);
				if (rc)
					goto out;
				break;
			case OCON_FS:
			case OCON_NETIF:
				rc = next_entry(buf, fp, sizeof(u32));
				if (rc)
					goto out;
				len = le32_to_cpu(buf[0]);

				rc = str_read(&c->u.name, GFP_KERNEL, fp, len);
				if (rc)
					goto out;

				if (i == OCON_FS)
					pr_warn("SELinux:  void and deprecated fs ocon %s\n",
						c->u.name);

				rc = context_read_and_validate(&c->context[0],
							       p, fp);
				if (rc)
					goto out;
				rc = context_read_and_validate(&c->context[1],
							       p, fp);
				if (rc)
					goto out;
				break;
			case OCON_PORT:
				rc = next_entry(buf, fp, sizeof(u32) * 3);
				if (rc)
					goto out;

				rc = -EINVAL;
				val = le32_to_cpu(buf[0]);
				if (val > U8_MAX)
					goto out;
				c->u.port.protocol = val;
				val = le32_to_cpu(buf[1]);
				if (val > U16_MAX)
					goto out;
				c->u.port.low_port = val;
				val = le32_to_cpu(buf[2]);
				if (val > U16_MAX)
					goto out;
				c->u.port.high_port = val;
				if (c->u.port.low_port == 0 ||
				    c->u.port.low_port > c->u.port.high_port)
					goto out;

				rc = context_read_and_validate(&c->context[0], p, fp);
				if (rc)
					goto out;
				break;
			case OCON_NODE:
				rc = next_entry(nodebuf, fp, sizeof(u32) * 2);
				if (rc)
					goto out;
				c->u.node.addr = nodebuf[0]; /* network order */
				c->u.node.mask = nodebuf[1]; /* network order */
				rc = context_read_and_validate(&c->context[0],
							       p, fp);
				if (rc)
					goto out;
				break;
			case OCON_FSUSE:
				rc = next_entry(buf, fp, sizeof(u32) * 2);
				if (rc)
					goto out;

				rc = -EINVAL;
				c->v.behavior = le32_to_cpu(buf[0]);
				/* Determined at runtime, not in policy DB. */
				if (c->v.behavior == SECURITY_FS_USE_MNTPOINT)
					goto out;
				if (c->v.behavior > SECURITY_FS_USE_MAX)
					goto out;

				len = le32_to_cpu(buf[1]);
				rc = str_read(&c->u.name, GFP_KERNEL, fp, len);
				if (rc)
					goto out;

				rc = context_read_and_validate(&c->context[0],
							       p, fp);
				if (rc)
					goto out;
				break;
			case OCON_NODE6: {
				int k;

				rc = next_entry(nodebuf, fp, sizeof(u32) * 8);
				if (rc)
					goto out;
				for (k = 0; k < 4; k++)
					c->u.node6.addr[k] = nodebuf[k];
				for (k = 0; k < 4; k++)
					c->u.node6.mask[k] = nodebuf[k + 4];
				rc = context_read_and_validate(&c->context[0],
							       p, fp);
				if (rc)
					goto out;
				break;
			}
			case OCON_IBPKEY: {
				u32 pkey_lo, pkey_hi;

				rc = next_entry(prefixbuf, fp, sizeof(u64));
				if (rc)
					goto out;

				/* we need to have subnet_prefix in CPU order */
				c->u.ibpkey.subnet_prefix =
					be64_to_cpu(prefixbuf[0]);

				rc = next_entry(buf, fp, sizeof(u32) * 2);
				if (rc)
					goto out;

				pkey_lo = le32_to_cpu(buf[0]);
				pkey_hi = le32_to_cpu(buf[1]);

				if (pkey_lo > U16_MAX || pkey_hi > U16_MAX) {
					rc = -EINVAL;
					goto out;
				}

				c->u.ibpkey.low_pkey = pkey_lo;
				c->u.ibpkey.high_pkey = pkey_hi;

				rc = context_read_and_validate(&c->context[0],
							       p, fp);
				if (rc)
					goto out;
				break;
			}
			case OCON_IBENDPORT: {
				u32 port;

				rc = next_entry(buf, fp, sizeof(u32) * 2);
				if (rc)
					goto out;
				len = le32_to_cpu(buf[0]);

				rc = str_read(&c->u.ibendport.dev_name,
					      GFP_KERNEL, fp, len);
				if (rc)
					goto out;

				port = le32_to_cpu(buf[1]);
				if (port > U8_MAX || port == 0) {
					rc = -EINVAL;
					goto out;
				}

				c->u.ibendport.port = port;

				rc = context_read_and_validate(&c->context[0],
							       p, fp);
				if (rc)
					goto out;
				break;
			} /* end case */
			} /* end switch */
		}
	}
	rc = 0;
out:
	if (rc)
		pr_err("SELinux:  invalid ocon\n");
	return rc;
}

/*
 * Read the configuration data from a policy database binary
 * representation file into a policy database structure.
 */
int policydb_read(struct policydb *p, struct policy_file *fp)
{
	struct role_allow *ra, *lra;
	struct role_trans_key *rtk = NULL;
	struct role_trans_datum *rtd = NULL;
	int rc;
	__le32 buf[4];
	u32 i, j, len, nprim, nel, perm, val;

	char *policydb_str;
	const struct policydb_compat_info *info;

	policydb_init(p);

	/* Read the magic number and string length. */
	rc = next_entry(buf, fp, sizeof(u32) * 2);
	if (rc)
		goto bad;

	rc = -EINVAL;
	if (le32_to_cpu(buf[0]) != POLICYDB_MAGIC) {
		pr_err("SELinux:  policydb magic number 0x%x does "
		       "not match expected magic number 0x%x\n",
		       le32_to_cpu(buf[0]), POLICYDB_MAGIC);
		goto bad;
	}

	rc = -EINVAL;
	len = le32_to_cpu(buf[1]);
	if (len != strlen(POLICYDB_STRING)) {
		pr_err("SELinux:  policydb string length %d does not "
		       "match expected length %zu\n",
		       len, strlen(POLICYDB_STRING));
		goto bad;
	}

	rc = str_read(&policydb_str, GFP_KERNEL, fp, len);
	if (rc) {
		if (rc == -ENOMEM) {
			pr_err("SELinux:  unable to allocate memory for policydb string of length %d\n",
			       len);
		} else {
			pr_err("SELinux:  truncated policydb string identifier\n");
		}
		goto bad;
	}

	rc = -EINVAL;
	if (strcmp(policydb_str, POLICYDB_STRING)) {
		pr_err("SELinux:  policydb string %s does not match "
		       "my string %s\n",
		       policydb_str, POLICYDB_STRING);
		kfree(policydb_str);
		goto bad;
	}
	/* Done with policydb_str. */
	kfree(policydb_str);
	policydb_str = NULL;

	/* Read the version and table sizes. */
	rc = next_entry(buf, fp, sizeof(u32) * 4);
	if (rc)
		goto bad;

	rc = -EINVAL;
	p->policyvers = le32_to_cpu(buf[0]);
	if (p->policyvers < POLICYDB_VERSION_MIN ||
	    p->policyvers > POLICYDB_VERSION_MAX) {
		pr_err("SELinux:  policydb version %d does not match "
		       "my version range %d-%d\n",
		       le32_to_cpu(buf[0]), POLICYDB_VERSION_MIN,
		       POLICYDB_VERSION_MAX);
		goto bad;
	}

	if ((le32_to_cpu(buf[1]) & POLICYDB_CONFIG_MLS)) {
		p->mls_enabled = 1;

		rc = -EINVAL;
		if (p->policyvers < POLICYDB_VERSION_MLS) {
			pr_err("SELinux: security policydb version %d "
			       "(MLS) not backwards compatible\n",
			       p->policyvers);
			goto bad;
		}
	}
	p->reject_unknown = !!(le32_to_cpu(buf[1]) & REJECT_UNKNOWN);
	p->allow_unknown = !!(le32_to_cpu(buf[1]) & ALLOW_UNKNOWN);

	if (p->policyvers >= POLICYDB_VERSION_POLCAP) {
		rc = ebitmap_read(&p->policycaps, fp);
		if (rc)
			goto bad;
	}

	if (p->policyvers >= POLICYDB_VERSION_PERMISSIVE) {
		rc = ebitmap_read(&p->permissive_map, fp);
		if (rc)
			goto bad;
	}

	if (p->policyvers >= POLICYDB_VERSION_NEVERAUDIT) {
		rc = ebitmap_read(&p->neveraudit_map, fp);
		if (rc)
			goto bad;
	}

	rc = -EINVAL;
	info = policydb_lookup_compat(p->policyvers);
	if (!info) {
		pr_err("SELinux:  unable to find policy compat info "
		       "for version %d\n",
		       p->policyvers);
		goto bad;
	}

	rc = -EINVAL;
	if (le32_to_cpu(buf[2]) != info->sym_num ||
	    le32_to_cpu(buf[3]) != info->ocon_num) {
		pr_err("SELinux:  policydb table sizes (%d,%d) do "
		       "not match mine (%d,%d)\n",
		       le32_to_cpu(buf[2]), le32_to_cpu(buf[3]), info->sym_num,
		       info->ocon_num);
		goto bad;
	}

	for (i = 0; i < info->sym_num; i++) {
		rc = next_entry(buf, fp, sizeof(u32) * 2);
		if (rc)
			goto bad;
		nprim = le32_to_cpu(buf[0]);
		nel = le32_to_cpu(buf[1]);

		/* every read_f() implementation reads at least 128 bytes
		 * for any valid entry
		 */
		rc = size_check(4 * sizeof(u32), nel, fp);
		if (rc)
			goto out;

		rc = symtab_init(&p->symtab[i], nel);
		if (rc)
			goto out;

		if (i == SYM_ROLES) {
			rc = roles_init(p);
			if (rc)
				goto out;
		}

		for (j = 0; j < nel; j++) {
			rc = read_f[i](p, &p->symtab[i], fp);
			if (rc)
				goto bad;
		}

		p->symtab[i].nprim = nprim;
	}

	rc = policydb_index(p);
	if (rc)
		goto bad;

	rc = -EINVAL;
	p->process_class = string_to_security_class(p, "process");
	if (!p->process_class) {
		pr_err("SELinux: process class is required, not defined in policy\n");
		goto bad;
	}

	rc = avtab_read(&p->te_avtab, fp, p);
	if (rc)
		goto bad;

	avtab_hash_eval(&p->te_avtab, "rules");

	if (p->policyvers >= POLICYDB_VERSION_BOOL) {
		rc = cond_read_list(p, fp);
		if (rc)
			goto bad;
	}

	rc = next_entry(buf, fp, sizeof(u32));
	if (rc)
		goto bad;
	nel = le32_to_cpu(buf[0]);

	/* we read at least 96 bytes for any valid role-transition */
	rc = size_check(3 * sizeof(u32), nel, fp);
	if (rc)
		goto bad;

	rc = hashtab_init(&p->role_tr, nel);
	if (rc)
		goto bad;
	for (i = 0; i < nel; i++) {
		rc = -ENOMEM;
		rtk = kmalloc_obj(*rtk);
		if (!rtk)
			goto bad;

		rc = -ENOMEM;
		rtd = kmalloc_obj(*rtd);
		if (!rtd)
			goto bad;

		rc = next_entry(buf, fp, sizeof(u32) * 3);
		if (rc)
			goto bad;

		rtk->role = le32_to_cpu(buf[0]);
		rtk->type = le32_to_cpu(buf[1]);
		rtd->new_role = le32_to_cpu(buf[2]);
		if (p->policyvers >= POLICYDB_VERSION_ROLETRANS) {
			rc = next_entry(buf, fp, sizeof(u32));
			if (rc)
				goto bad;
			rc = -EINVAL;
			val = le32_to_cpu(buf[0]);
			if (val > U16_MAX)
				goto bad;
			rtk->tclass = val;
		} else
			rtk->tclass = p->process_class;

		rc = -EINVAL;
		if (!policydb_role_isvalid(p, rtk->role) ||
		    !policydb_type_isvalid(p, rtk->type) ||
		    !policydb_class_isvalid(p, rtk->tclass) ||
		    !policydb_role_isvalid(p, rtd->new_role))
			goto bad;

		rc = hashtab_insert(&p->role_tr, rtk, rtd, roletr_key_params);
		if (rc)
			goto bad;

		rtk = NULL;
		rtd = NULL;
	}

	hash_eval(&p->role_tr, "roletr", NULL);

	rc = next_entry(buf, fp, sizeof(u32));
	if (rc)
		goto bad;
	nel = le32_to_cpu(buf[0]);
	lra = NULL;
	for (i = 0; i < nel; i++) {
		rc = -ENOMEM;
		ra = kzalloc_obj(*ra);
		if (!ra)
			goto bad;
		if (lra)
			lra->next = ra;
		else
			p->role_allow = ra;
		rc = next_entry(buf, fp, sizeof(u32) * 2);
		if (rc)
			goto bad;

		rc = -EINVAL;
		ra->role = le32_to_cpu(buf[0]);
		ra->new_role = le32_to_cpu(buf[1]);
		if (!policydb_role_isvalid(p, ra->role) ||
		    !policydb_role_isvalid(p, ra->new_role))
			goto bad;
		lra = ra;
	}

	rc = filename_trans_read(p, fp);
	if (rc)
		goto bad;

	rc = -EINVAL;
	perm = string_to_av_perm(p, p->process_class, "transition");
	if (!perm) {
		pr_err("SELinux: process transition permission is required, not defined in policy\n");
		goto bad;
	}
	p->process_trans_perms = perm;
	perm = string_to_av_perm(p, p->process_class, "dyntransition");
	if (!perm) {
		pr_err("SELinux: process dyntransition permission is required, not defined in policy\n");
		goto bad;
	}
	p->process_trans_perms |= perm;

	rc = ocontext_read(p, info, fp);
	if (rc)
		goto bad;

	rc = genfs_read(p, fp);
	if (rc)
		goto bad;

	rc = range_read(p, fp);
	if (rc)
		goto bad;

	rc = -ENOMEM;
	p->type_attr_map_array = kvzalloc_objs(*p->type_attr_map_array,
					       p->p_types.nprim);
	if (!p->type_attr_map_array)
		goto bad;

	/* just in case ebitmap_init() becomes more than just a memset(0): */
	for (i = 0; i < p->p_types.nprim; i++)
		ebitmap_init(&p->type_attr_map_array[i]);

	for (i = 0; i < p->p_types.nprim; i++) {
		struct ebitmap *e = &p->type_attr_map_array[i];

		if (p->policyvers >= POLICYDB_VERSION_AVTAB) {
			rc = ebitmap_read(e, fp);
			if (rc)
				goto bad;
		}

		rc = -EINVAL;
		if (ebitmap_get_highest_set_bit(e) >= p->p_types.nprim)
			goto bad;

		/* add the type itself as the degenerate case */
		rc = ebitmap_set_bit(e, i, 1);
		if (rc)
			goto bad;
	}

	rc = policydb_bounds_sanity_check(p);
	if (rc)
		goto bad;

	rc = 0;
out:
	return rc;
bad:
	kfree(rtk);
	kfree(rtd);
	policydb_destroy(p);
	goto out;
}

/*
 * Write a MLS level structure to a policydb binary
 * representation file.
 */
static int mls_write_level(struct mls_level *l, struct policy_file *fp)
{
	__le32 buf[1];
	int rc;

	buf[0] = cpu_to_le32(l->sens);
	rc = put_entry(buf, sizeof(u32), 1, fp);
	if (rc)
		return rc;

	rc = ebitmap_write(&l->cat, fp);
	if (rc)
		return rc;

	return 0;
}

/*
 * Write a MLS range structure to a policydb binary
 * representation file.
 */
static int mls_write_range_helper(struct mls_range *r, struct policy_file *fp)
{
	__le32 buf[3];
	size_t items;
	int rc, eq;

	eq = mls_level_eq(&r->level[1], &r->level[0]);

	if (eq)
		items = 2;
	else
		items = 3;
	buf[0] = cpu_to_le32(items - 1);
	buf[1] = cpu_to_le32(r->level[0].sens);
	if (!eq)
		buf[2] = cpu_to_le32(r->level[1].sens);

	BUG_ON(items > ARRAY_SIZE(buf));

	rc = put_entry(buf, sizeof(u32), items, fp);
	if (rc)
		return rc;

	rc = ebitmap_write(&r->level[0].cat, fp);
	if (rc)
		return rc;
	if (!eq) {
		rc = ebitmap_write(&r->level[1].cat, fp);
		if (rc)
			return rc;
	}

	return 0;
}

static int sens_write(void *vkey, void *datum, void *ptr)
{
	char *key = vkey;
	struct level_datum *levdatum = datum;
	struct policy_data *pd = ptr;
	struct policy_file *fp = pd->fp;
	__le32 buf[2];
	size_t len;
	int rc;

	len = strlen(key);
	buf[0] = cpu_to_le32(len);
	buf[1] = cpu_to_le32(levdatum->isalias);
	rc = put_entry(buf, sizeof(u32), 2, fp);
	if (rc)
		return rc;

	rc = put_entry(key, 1, len, fp);
	if (rc)
		return rc;

	rc = mls_write_level(&levdatum->level, fp);
	if (rc)
		return rc;

	return 0;
}

static int cat_write(void *vkey, void *datum, void *ptr)
{
	char *key = vkey;
	struct cat_datum *catdatum = datum;
	struct policy_data *pd = ptr;
	struct policy_file *fp = pd->fp;
	__le32 buf[3];
	size_t len;
	int rc;

	len = strlen(key);
	buf[0] = cpu_to_le32(len);
	buf[1] = cpu_to_le32(catdatum->value);
	buf[2] = cpu_to_le32(catdatum->isalias);
	rc = put_entry(buf, sizeof(u32), 3, fp);
	if (rc)
		return rc;

	rc = put_entry(key, 1, len, fp);
	if (rc)
		return rc;

	return 0;
}

static int role_trans_write_one(void *key, void *datum, void *ptr)
{
	struct role_trans_key *rtk = key;
	struct role_trans_datum *rtd = datum;
	struct policy_data *pd = ptr;
	struct policy_file *fp = pd->fp;
	struct policydb *p = pd->p;
	__le32 buf[3];
	int rc;

	buf[0] = cpu_to_le32(rtk->role);
	buf[1] = cpu_to_le32(rtk->type);
	buf[2] = cpu_to_le32(rtd->new_role);
	rc = put_entry(buf, sizeof(u32), 3, fp);
	if (rc)
		return rc;
	if (p->policyvers >= POLICYDB_VERSION_ROLETRANS) {
		buf[0] = cpu_to_le32(rtk->tclass);
		rc = put_entry(buf, sizeof(u32), 1, fp);
		if (rc)
			return rc;
	}
	return 0;
}

static int role_trans_write(struct policydb *p, struct policy_file *fp)
{
	struct policy_data pd = { .p = p, .fp = fp };
	__le32 buf[1];
	int rc;

	buf[0] = cpu_to_le32(p->role_tr.nel);
	rc = put_entry(buf, sizeof(u32), 1, fp);
	if (rc)
		return rc;

	return hashtab_map(&p->role_tr, role_trans_write_one, &pd);
}

static int role_allow_write(struct role_allow *r, struct policy_file *fp)
{
	struct role_allow *ra;
	__le32 buf[2];
	size_t nel;
	int rc;

	nel = 0;
	for (ra = r; ra; ra = ra->next)
		nel++;
	buf[0] = cpu_to_le32(nel);
	rc = put_entry(buf, sizeof(u32), 1, fp);
	if (rc)
		return rc;
	for (ra = r; ra; ra = ra->next) {
		buf[0] = cpu_to_le32(ra->role);
		buf[1] = cpu_to_le32(ra->new_role);
		rc = put_entry(buf, sizeof(u32), 2, fp);
		if (rc)
			return rc;
	}
	return 0;
}

/*
 * Write a security context structure
 * to a policydb binary representation file.
 */
static int context_write(struct policydb *p, struct context *c, struct policy_file *fp)
{
	int rc;
	__le32 buf[3];

	buf[0] = cpu_to_le32(c->user);
	buf[1] = cpu_to_le32(c->role);
	buf[2] = cpu_to_le32(c->type);

	rc = put_entry(buf, sizeof(u32), 3, fp);
	if (rc)
		return rc;

	rc = mls_write_range_helper(&c->range, fp);
	if (rc)
		return rc;

	return 0;
}

/*
 * The following *_write functions are used to
 * write the symbol data to a policy database
 * binary representation file.
 */

static int perm_write(void *vkey, void *datum, void *fp)
{
	char *key = vkey;
	struct perm_datum *perdatum = datum;
	__le32 buf[2];
	size_t len;
	int rc;

	len = strlen(key);
	buf[0] = cpu_to_le32(len);
	buf[1] = cpu_to_le32(perdatum->value);
	rc = put_entry(buf, sizeof(u32), 2, fp);
	if (rc)
		return rc;

	rc = put_entry(key, 1, len, fp);
	if (rc)
		return rc;

	return 0;
}

static int common_write(void *vkey, void *datum, void *ptr)
{
	char *key = vkey;
	struct common_datum *comdatum = datum;
	struct policy_data *pd = ptr;
	struct policy_file *fp = pd->fp;
	__le32 buf[4];
	size_t len;
	int rc;

	len = strlen(key);
	buf[0] = cpu_to_le32(len);
	buf[1] = cpu_to_le32(comdatum->value);
	buf[2] = cpu_to_le32(comdatum->permissions.nprim);
	buf[3] = cpu_to_le32(comdatum->permissions.table.nel);
	rc = put_entry(buf, sizeof(u32), 4, fp);
	if (rc)
		return rc;

	rc = put_entry(key, 1, len, fp);
	if (rc)
		return rc;

	rc = hashtab_map(&comdatum->permissions.table, perm_write, fp);
	if (rc)
		return rc;

	return 0;
}

static int type_set_write(struct type_set *t, struct policy_file *fp)
{
	int rc;
	__le32 buf[1];

	if (ebitmap_write(&t->types, fp))
		return -EINVAL;
	if (ebitmap_write(&t->negset, fp))
		return -EINVAL;

	buf[0] = cpu_to_le32(t->flags);
	rc = put_entry(buf, sizeof(u32), 1, fp);
	if (rc)
		return -EINVAL;

	return 0;
}

static int write_cons_helper(struct policydb *p, struct constraint_node *node,
			     struct policy_file *fp)
{
	struct constraint_node *c;
	struct constraint_expr *e;
	__le32 buf[3];
	u32 nel;
	int rc;

	for (c = node; c; c = c->next) {
		nel = 0;
		for (e = c->expr; e; e = e->next)
			nel++;
		buf[0] = cpu_to_le32(c->permissions);
		buf[1] = cpu_to_le32(nel);
		rc = put_entry(buf, sizeof(u32), 2, fp);
		if (rc)
			return rc;
		for (e = c->expr; e; e = e->next) {
			buf[0] = cpu_to_le32(e->expr_type);
			buf[1] = cpu_to_le32(e->attr);
			buf[2] = cpu_to_le32(e->op);
			rc = put_entry(buf, sizeof(u32), 3, fp);
			if (rc)
				return rc;

			switch (e->expr_type) {
			case CEXPR_NAMES:
				rc = ebitmap_write(&e->names, fp);
				if (rc)
					return rc;
				if (p->policyvers >=
				    POLICYDB_VERSION_CONSTRAINT_NAMES) {
					rc = type_set_write(e->type_names, fp);
					if (rc)
						return rc;
				}
				break;
			default:
				break;
			}
		}
	}

	return 0;
}

static int class_write(void *vkey, void *datum, void *ptr)
{
	char *key = vkey;
	struct class_datum *cladatum = datum;
	struct policy_data *pd = ptr;
	struct policy_file *fp = pd->fp;
	struct policydb *p = pd->p;
	struct constraint_node *c;
	__le32 buf[6];
	u32 ncons;
	size_t len, len2;
	int rc;

	len = strlen(key);
	if (cladatum->comkey)
		len2 = strlen(cladatum->comkey);
	else
		len2 = 0;

	ncons = 0;
	for (c = cladatum->constraints; c; c = c->next)
		ncons++;

	buf[0] = cpu_to_le32(len);
	buf[1] = cpu_to_le32(len2);
	buf[2] = cpu_to_le32(cladatum->value);
	buf[3] = cpu_to_le32(cladatum->permissions.nprim);
	buf[4] = cpu_to_le32(cladatum->permissions.table.nel);
	buf[5] = cpu_to_le32(ncons);
	rc = put_entry(buf, sizeof(u32), 6, fp);
	if (rc)
		return rc;

	rc = put_entry(key, 1, len, fp);
	if (rc)
		return rc;

	if (cladatum->comkey) {
		rc = put_entry(cladatum->comkey, 1, len2, fp);
		if (rc)
			return rc;
	}

	rc = hashtab_map(&cladatum->permissions.table, perm_write, fp);
	if (rc)
		return rc;

	rc = write_cons_helper(p, cladatum->constraints, fp);
	if (rc)
		return rc;

	/* write out the validatetrans rule */
	ncons = 0;
	for (c = cladatum->validatetrans; c; c = c->next)
		ncons++;

	buf[0] = cpu_to_le32(ncons);
	rc = put_entry(buf, sizeof(u32), 1, fp);
	if (rc)
		return rc;

	rc = write_cons_helper(p, cladatum->validatetrans, fp);
	if (rc)
		return rc;

	if (p->policyvers >= POLICYDB_VERSION_NEW_OBJECT_DEFAULTS) {
		buf[0] = cpu_to_le32(cladatum->default_user);
		buf[1] = cpu_to_le32(cladatum->default_role);
		buf[2] = cpu_to_le32(cladatum->default_range);

		rc = put_entry(buf, sizeof(uint32_t), 3, fp);
		if (rc)
			return rc;
	}

	if (p->policyvers >= POLICYDB_VERSION_DEFAULT_TYPE) {
		buf[0] = cpu_to_le32(cladatum->default_type);
		rc = put_entry(buf, sizeof(uint32_t), 1, fp);
		if (rc)
			return rc;
	}

	return 0;
}

static int role_write(void *vkey, void *datum, void *ptr)
{
	char *key = vkey;
	struct role_datum *role = datum;
	struct policy_data *pd = ptr;
	struct policy_file *fp = pd->fp;
	struct policydb *p = pd->p;
	__le32 buf[3];
	size_t items, len;
	int rc;

	len = strlen(key);
	items = 0;
	buf[items++] = cpu_to_le32(len);
	buf[items++] = cpu_to_le32(role->value);
	if (p->policyvers >= POLICYDB_VERSION_BOUNDARY)
		buf[items++] = cpu_to_le32(role->bounds);

	BUG_ON(items > ARRAY_SIZE(buf));

	rc = put_entry(buf, sizeof(u32), items, fp);
	if (rc)
		return rc;

	rc = put_entry(key, 1, len, fp);
	if (rc)
		return rc;

	rc = ebitmap_write(&role->dominates, fp);
	if (rc)
		return rc;

	rc = ebitmap_write(&role->types, fp);
	if (rc)
		return rc;

	return 0;
}

static int type_write(void *vkey, void *datum, void *ptr)
{
	char *key = vkey;
	struct type_datum *typdatum = datum;
	struct policy_data *pd = ptr;
	struct policydb *p = pd->p;
	struct policy_file *fp = pd->fp;
	__le32 buf[4];
	int rc;
	size_t items, len;

	len = strlen(key);
	items = 0;
	buf[items++] = cpu_to_le32(len);
	buf[items++] = cpu_to_le32(typdatum->value);
	if (p->policyvers >= POLICYDB_VERSION_BOUNDARY) {
		u32 properties = 0;

		if (typdatum->primary)
			properties |= TYPEDATUM_PROPERTY_PRIMARY;

		if (typdatum->attribute)
			properties |= TYPEDATUM_PROPERTY_ATTRIBUTE;

		buf[items++] = cpu_to_le32(properties);
		buf[items++] = cpu_to_le32(typdatum->bounds);
	} else {
		buf[items++] = cpu_to_le32(typdatum->primary);
	}
	BUG_ON(items > ARRAY_SIZE(buf));
	rc = put_entry(buf, sizeof(u32), items, fp);
	if (rc)
		return rc;

	rc = put_entry(key, 1, len, fp);
	if (rc)
		return rc;

	return 0;
}

static int user_write(void *vkey, void *datum, void *ptr)
{
	char *key = vkey;
	struct user_datum *usrdatum = datum;
	struct policy_data *pd = ptr;
	struct policydb *p = pd->p;
	struct policy_file *fp = pd->fp;
	__le32 buf[3];
	size_t items, len;
	int rc;

	len = strlen(key);
	items = 0;
	buf[items++] = cpu_to_le32(len);
	buf[items++] = cpu_to_le32(usrdatum->value);
	if (p->policyvers >= POLICYDB_VERSION_BOUNDARY)
		buf[items++] = cpu_to_le32(usrdatum->bounds);
	BUG_ON(items > ARRAY_SIZE(buf));
	rc = put_entry(buf, sizeof(u32), items, fp);
	if (rc)
		return rc;

	rc = put_entry(key, 1, len, fp);
	if (rc)
		return rc;

	rc = ebitmap_write(&usrdatum->roles, fp);
	if (rc)
		return rc;

	rc = mls_write_range_helper(&usrdatum->range, fp);
	if (rc)
		return rc;

	rc = mls_write_level(&usrdatum->dfltlevel, fp);
	if (rc)
		return rc;

	return 0;
}

/* clang-format off */
static int (*const write_f[SYM_NUM])(void *key, void *datum, void *datap) = {
	common_write,
	class_write,
	role_write,
	type_write,
	user_write,
	cond_write_bool,
	sens_write,
	cat_write,
};
/* clang-format on */

static int ocontext_write(struct policydb *p,
			  const struct policydb_compat_info *info,
			  struct policy_file *fp)
{
	unsigned int i, j;
	int rc;
	size_t nel, len;
	__be64 prefixbuf[1];
	__le32 buf[3];
	u32 nodebuf[8];
	struct ocontext *c;
	for (i = 0; i < info->ocon_num; i++) {
		nel = 0;
		for (c = p->ocontexts[i]; c; c = c->next)
			nel++;
		buf[0] = cpu_to_le32(nel);
		rc = put_entry(buf, sizeof(u32), 1, fp);
		if (rc)
			return rc;
		for (c = p->ocontexts[i]; c; c = c->next) {
			switch (i) {
			case OCON_ISID:
				buf[0] = cpu_to_le32(c->sid[0]);
				rc = put_entry(buf, sizeof(u32), 1, fp);
				if (rc)
					return rc;
				rc = context_write(p, &c->context[0], fp);
				if (rc)
					return rc;
				break;
			case OCON_FS:
			case OCON_NETIF:
				len = strlen(c->u.name);
				buf[0] = cpu_to_le32(len);
				rc = put_entry(buf, sizeof(u32), 1, fp);
				if (rc)
					return rc;
				rc = put_entry(c->u.name, 1, len, fp);
				if (rc)
					return rc;
				rc = context_write(p, &c->context[0], fp);
				if (rc)
					return rc;
				rc = context_write(p, &c->context[1], fp);
				if (rc)
					return rc;
				break;
			case OCON_PORT:
				buf[0] = cpu_to_le32(c->u.port.protocol);
				buf[1] = cpu_to_le32(c->u.port.low_port);
				buf[2] = cpu_to_le32(c->u.port.high_port);
				rc = put_entry(buf, sizeof(u32), 3, fp);
				if (rc)
					return rc;
				rc = context_write(p, &c->context[0], fp);
				if (rc)
					return rc;
				break;
			case OCON_NODE:
				nodebuf[0] = c->u.node.addr; /* network order */
				nodebuf[1] = c->u.node.mask; /* network order */
				rc = put_entry(nodebuf, sizeof(u32), 2, fp);
				if (rc)
					return rc;
				rc = context_write(p, &c->context[0], fp);
				if (rc)
					return rc;
				break;
			case OCON_FSUSE:
				buf[0] = cpu_to_le32(c->v.behavior);
				len = strlen(c->u.name);
				buf[1] = cpu_to_le32(len);
				rc = put_entry(buf, sizeof(u32), 2, fp);
				if (rc)
					return rc;
				rc = put_entry(c->u.name, 1, len, fp);
				if (rc)
					return rc;
				rc = context_write(p, &c->context[0], fp);
				if (rc)
					return rc;
				break;
			case OCON_NODE6:
				for (j = 0; j < 4; j++)
					nodebuf[j] =
						c->u.node6.addr
							[j]; /* network order */
				for (j = 0; j < 4; j++)
					nodebuf[j + 4] =
						c->u.node6.mask
							[j]; /* network order */
				rc = put_entry(nodebuf, sizeof(u32), 8, fp);
				if (rc)
					return rc;
				rc = context_write(p, &c->context[0], fp);
				if (rc)
					return rc;
				break;
			case OCON_IBPKEY:
				/* subnet_prefix is in CPU order */
				prefixbuf[0] =
					cpu_to_be64(c->u.ibpkey.subnet_prefix);

				rc = put_entry(prefixbuf, sizeof(u64), 1, fp);
				if (rc)
					return rc;

				buf[0] = cpu_to_le32(c->u.ibpkey.low_pkey);
				buf[1] = cpu_to_le32(c->u.ibpkey.high_pkey);

				rc = put_entry(buf, sizeof(u32), 2, fp);
				if (rc)
					return rc;
				rc = context_write(p, &c->context[0], fp);
				if (rc)
					return rc;
				break;
			case OCON_IBENDPORT:
				len = strlen(c->u.ibendport.dev_name);
				buf[0] = cpu_to_le32(len);
				buf[1] = cpu_to_le32(c->u.ibendport.port);
				rc = put_entry(buf, sizeof(u32), 2, fp);
				if (rc)
					return rc;
				rc = put_entry(c->u.ibendport.dev_name, 1, len,
					       fp);
				if (rc)
					return rc;
				rc = context_write(p, &c->context[0], fp);
				if (rc)
					return rc;
				break;
			}
		}
	}
	return 0;
}

static int genfs_write(struct policydb *p, struct policy_file *fp)
{
	struct genfs *genfs;
	struct ocontext *c;
	size_t len;
	__le32 buf[1];
	int rc;

	len = 0;
	for (genfs = p->genfs; genfs; genfs = genfs->next)
		len++;
	buf[0] = cpu_to_le32(len);
	rc = put_entry(buf, sizeof(u32), 1, fp);
	if (rc)
		return rc;
	for (genfs = p->genfs; genfs; genfs = genfs->next) {
		len = strlen(genfs->fstype);
		buf[0] = cpu_to_le32(len);
		rc = put_entry(buf, sizeof(u32), 1, fp);
		if (rc)
			return rc;
		rc = put_entry(genfs->fstype, 1, len, fp);
		if (rc)
			return rc;
		len = 0;
		for (c = genfs->head; c; c = c->next)
			len++;
		buf[0] = cpu_to_le32(len);
		rc = put_entry(buf, sizeof(u32), 1, fp);
		if (rc)
			return rc;
		for (c = genfs->head; c; c = c->next) {
			len = strlen(c->u.name);
			buf[0] = cpu_to_le32(len);
			rc = put_entry(buf, sizeof(u32), 1, fp);
			if (rc)
				return rc;
			rc = put_entry(c->u.name, 1, len, fp);
			if (rc)
				return rc;
			buf[0] = cpu_to_le32(c->v.sclass);
			rc = put_entry(buf, sizeof(u32), 1, fp);
			if (rc)
				return rc;
			rc = context_write(p, &c->context[0], fp);
			if (rc)
				return rc;
		}
	}
	return 0;
}

static int range_write_helper(void *key, void *data, void *ptr)
{
	__le32 buf[2];
	struct range_trans *rt = key;
	struct mls_range *r = data;
	struct policy_data *pd = ptr;
	struct policy_file *fp = pd->fp;
	struct policydb *p = pd->p;
	int rc;

	buf[0] = cpu_to_le32(rt->source_type);
	buf[1] = cpu_to_le32(rt->target_type);
	rc = put_entry(buf, sizeof(u32), 2, fp);
	if (rc)
		return rc;
	if (p->policyvers >= POLICYDB_VERSION_RANGETRANS) {
		buf[0] = cpu_to_le32(rt->target_class);
		rc = put_entry(buf, sizeof(u32), 1, fp);
		if (rc)
			return rc;
	}
	rc = mls_write_range_helper(r, fp);
	if (rc)
		return rc;

	return 0;
}

static int range_write(struct policydb *p, struct policy_file *fp)
{
	__le32 buf[1];
	int rc;
	struct policy_data pd;

	pd.p = p;
	pd.fp = fp;

	buf[0] = cpu_to_le32(p->range_tr.nel);
	rc = put_entry(buf, sizeof(u32), 1, fp);
	if (rc)
		return rc;

	/* actually write all of the entries */
	rc = hashtab_map(&p->range_tr, range_write_helper, &pd);
	if (rc)
		return rc;

	return 0;
}

static int filename_write_helper_compat(void *key, void *data, void *ptr)
{
	struct filename_trans_key *ft = key;
	struct filename_trans_datum *datum = data;
	struct ebitmap_node *node;
	struct policy_file *fp = ptr;
	__le32 buf[4];
	int rc;
	u32 bit, len = strlen(ft->name);

	do {
		ebitmap_for_each_positive_bit(&datum->stypes, node, bit)
		{
			buf[0] = cpu_to_le32(len);
			rc = put_entry(buf, sizeof(u32), 1, fp);
			if (rc)
				return rc;

			rc = put_entry(ft->name, sizeof(char), len, fp);
			if (rc)
				return rc;

			buf[0] = cpu_to_le32(bit + 1);
			buf[1] = cpu_to_le32(ft->ttype);
			buf[2] = cpu_to_le32(ft->tclass);
			buf[3] = cpu_to_le32(datum->otype);

			rc = put_entry(buf, sizeof(u32), 4, fp);
			if (rc)
				return rc;
		}

		datum = datum->next;
	} while (unlikely(datum));

	return 0;
}

static int filename_write_helper(void *key, void *data, void *ptr)
{
	struct filename_trans_key *ft = key;
	struct filename_trans_datum *datum;
	struct policy_file *fp = ptr;
	__le32 buf[3];
	int rc;
	u32 ndatum, len = strlen(ft->name);

	buf[0] = cpu_to_le32(len);
	rc = put_entry(buf, sizeof(u32), 1, fp);
	if (rc)
		return rc;

	rc = put_entry(ft->name, sizeof(char), len, fp);
	if (rc)
		return rc;

	ndatum = 0;
	datum = data;
	do {
		ndatum++;
		datum = datum->next;
	} while (unlikely(datum));

	buf[0] = cpu_to_le32(ft->ttype);
	buf[1] = cpu_to_le32(ft->tclass);
	buf[2] = cpu_to_le32(ndatum);
	rc = put_entry(buf, sizeof(u32), 3, fp);
	if (rc)
		return rc;

	datum = data;
	do {
		rc = ebitmap_write(&datum->stypes, fp);
		if (rc)
			return rc;

		buf[0] = cpu_to_le32(datum->otype);
		rc = put_entry(buf, sizeof(u32), 1, fp);
		if (rc)
			return rc;

		datum = datum->next;
	} while (unlikely(datum));

	return 0;
}

static int filename_trans_write(struct policydb *p, struct policy_file *fp)
{
	__le32 buf[1];
	int rc;

	if (p->policyvers < POLICYDB_VERSION_FILENAME_TRANS)
		return 0;

	if (p->policyvers < POLICYDB_VERSION_COMP_FTRANS) {
		buf[0] = cpu_to_le32(p->compat_filename_trans_count);
		rc = put_entry(buf, sizeof(u32), 1, fp);
		if (rc)
			return rc;

		rc = hashtab_map(&p->filename_trans,
				 filename_write_helper_compat, fp);
	} else {
		buf[0] = cpu_to_le32(p->filename_trans.nel);
		rc = put_entry(buf, sizeof(u32), 1, fp);
		if (rc)
			return rc;

		rc = hashtab_map(&p->filename_trans, filename_write_helper, fp);
	}
	return rc;
}

/*
 * Write the configuration data in a policy database
 * structure to a policy database binary representation
 * file.
 */
int policydb_write(struct policydb *p, struct policy_file *fp)
{
	unsigned int num_syms;
	int rc;
	__le32 buf[4];
	u32 config, i;
	size_t len;
	const struct policydb_compat_info *info;

	/*
	 * refuse to write policy older than compressed avtab
	 * to simplify the writer.  There are other tests dropped
	 * since we assume this throughout the writer code.  Be
	 * careful if you ever try to remove this restriction
	 */
	if (p->policyvers < POLICYDB_VERSION_AVTAB) {
		pr_err("SELinux: refusing to write policy version %d."
		       "  Because it is less than version %d\n",
		       p->policyvers, POLICYDB_VERSION_AVTAB);
		return -EINVAL;
	}

	config = 0;
	if (p->mls_enabled)
		config |= POLICYDB_CONFIG_MLS;

	if (p->reject_unknown)
		config |= REJECT_UNKNOWN;
	if (p->allow_unknown)
		config |= ALLOW_UNKNOWN;

	/* Write the magic number and string identifiers. */
	buf[0] = cpu_to_le32(POLICYDB_MAGIC);
	len = strlen(POLICYDB_STRING);
	buf[1] = cpu_to_le32(len);
	rc = put_entry(buf, sizeof(u32), 2, fp);
	if (rc)
		return rc;
	rc = put_entry(POLICYDB_STRING, 1, len, fp);
	if (rc)
		return rc;

	/* Write the version, config, and table sizes. */
	info = policydb_lookup_compat(p->policyvers);
	if (!info) {
		pr_err("SELinux: compatibility lookup failed for policy "
		       "version %d\n",
		       p->policyvers);
		return -EINVAL;
	}

	buf[0] = cpu_to_le32(p->policyvers);
	buf[1] = cpu_to_le32(config);
	buf[2] = cpu_to_le32(info->sym_num);
	buf[3] = cpu_to_le32(info->ocon_num);

	rc = put_entry(buf, sizeof(u32), 4, fp);
	if (rc)
		return rc;

	if (p->policyvers >= POLICYDB_VERSION_POLCAP) {
		rc = ebitmap_write(&p->policycaps, fp);
		if (rc)
			return rc;
	}

	if (p->policyvers >= POLICYDB_VERSION_PERMISSIVE) {
		rc = ebitmap_write(&p->permissive_map, fp);
		if (rc)
			return rc;
	}

	if (p->policyvers >= POLICYDB_VERSION_NEVERAUDIT) {
		rc = ebitmap_write(&p->neveraudit_map, fp);
		if (rc)
			return rc;
	}

	num_syms = info->sym_num;
	for (i = 0; i < num_syms; i++) {
		struct policy_data pd;

		pd.fp = fp;
		pd.p = p;

		buf[0] = cpu_to_le32(p->symtab[i].nprim);
		buf[1] = cpu_to_le32(p->symtab[i].table.nel);

		rc = put_entry(buf, sizeof(u32), 2, fp);
		if (rc)
			return rc;
		rc = hashtab_map(&p->symtab[i].table, write_f[i], &pd);
		if (rc)
			return rc;
	}

	rc = avtab_write(p, &p->te_avtab, fp);
	if (rc)
		return rc;

	rc = cond_write_list(p, fp);
	if (rc)
		return rc;

	rc = role_trans_write(p, fp);
	if (rc)
		return rc;

	rc = role_allow_write(p->role_allow, fp);
	if (rc)
		return rc;

	rc = filename_trans_write(p, fp);
	if (rc)
		return rc;

	rc = ocontext_write(p, info, fp);
	if (rc)
		return rc;

	rc = genfs_write(p, fp);
	if (rc)
		return rc;

	rc = range_write(p, fp);
	if (rc)
		return rc;

	for (i = 0; i < p->p_types.nprim; i++) {
		struct ebitmap *e = &p->type_attr_map_array[i];

		rc = ebitmap_write(e, fp);
		if (rc)
			return rc;
	}

	return 0;
}
