android_kernel_xiaomi_sm8350/security/selinux/ss/policydb.c
Stephen Smalley 282c1f5eba [PATCH] selinux: Fix NULL deref in policydb_destroy
This patch fixes a possible NULL dereference in policydb_destroy, where
p->type_attr_map can be NULL if policydb_destroy is called to clean up a
partially loaded policy upon an error during policy load.  Please apply.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-23 16:38:38 -07:00

1894 lines
38 KiB
C

/*
* Implementation of the policy database.
*
* Author : Stephen Smalley, <sds@epoch.ncsc.mil>
*/
/*
* Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
*
* Support for enhanced MLS infrastructure.
*
* Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
*
* Added conditional policy language extensions
*
* Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
* Copyright (C) 2003 - 2004 Tresys Technology, LLC
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, version 2.
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/errno.h>
#include "security.h"
#include "policydb.h"
#include "conditional.h"
#include "mls.h"
#define _DEBUG_HASHES
#ifdef DEBUG_HASHES
static char *symtab_name[SYM_NUM] = {
"common prefixes",
"classes",
"roles",
"types",
"users",
"bools",
"levels",
"categories",
};
#endif
int selinux_mls_enabled = 0;
static unsigned int symtab_sizes[SYM_NUM] = {
2,
32,
16,
512,
128,
16,
16,
16,
};
struct policydb_compat_info {
int version;
int sym_num;
int ocon_num;
};
/* These need to be updated if SYM_NUM or OCON_NUM changes */
static struct policydb_compat_info policydb_compat[] = {
{
.version = POLICYDB_VERSION_BASE,
.sym_num = SYM_NUM - 3,
.ocon_num = OCON_NUM - 1,
},
{
.version = POLICYDB_VERSION_BOOL,
.sym_num = SYM_NUM - 2,
.ocon_num = OCON_NUM - 1,
},
{
.version = POLICYDB_VERSION_IPV6,
.sym_num = SYM_NUM - 2,
.ocon_num = OCON_NUM,
},
{
.version = POLICYDB_VERSION_NLCLASS,
.sym_num = SYM_NUM - 2,
.ocon_num = OCON_NUM,
},
{
.version = POLICYDB_VERSION_MLS,
.sym_num = SYM_NUM,
.ocon_num = OCON_NUM,
},
{
.version = POLICYDB_VERSION_AVTAB,
.sym_num = SYM_NUM,
.ocon_num = OCON_NUM,
},
};
static struct policydb_compat_info *policydb_lookup_compat(int version)
{
int i;
struct policydb_compat_info *info = NULL;
for (i = 0; i < sizeof(policydb_compat)/sizeof(*info); i++) {
if (policydb_compat[i].version == version) {
info = &policydb_compat[i];
break;
}
}
return info;
}
/*
* Initialize the role table.
*/
static int roles_init(struct policydb *p)
{
char *key = NULL;
int rc;
struct role_datum *role;
role = kmalloc(sizeof(*role), GFP_KERNEL);
if (!role) {
rc = -ENOMEM;
goto out;
}
memset(role, 0, sizeof(*role));
role->value = ++p->p_roles.nprim;
if (role->value != OBJECT_R_VAL) {
rc = -EINVAL;
goto out_free_role;
}
key = kmalloc(strlen(OBJECT_R)+1,GFP_KERNEL);
if (!key) {
rc = -ENOMEM;
goto out_free_role;
}
strcpy(key, OBJECT_R);
rc = hashtab_insert(p->p_roles.table, key, role);
if (rc)
goto out_free_key;
out:
return rc;
out_free_key:
kfree(key);
out_free_role:
kfree(role);
goto out;
}
/*
* Initialize a policy database structure.
*/
static int policydb_init(struct policydb *p)
{
int i, rc;
memset(p, 0, sizeof(*p));
for (i = 0; i < SYM_NUM; i++) {
rc = symtab_init(&p->symtab[i], symtab_sizes[i]);
if (rc)
goto out_free_symtab;
}
rc = avtab_init(&p->te_avtab);
if (rc)
goto out_free_symtab;
rc = roles_init(p);
if (rc)
goto out_free_avtab;
rc = cond_policydb_init(p);
if (rc)
goto out_free_avtab;
out:
return rc;
out_free_avtab:
avtab_destroy(&p->te_avtab);
out_free_symtab:
for (i = 0; i < SYM_NUM; i++)
hashtab_destroy(p->symtab[i].table);
goto out;
}
/*
* 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->p_common_val_to_name[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->p_class_val_to_name[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)
return -EINVAL;
p->p_role_val_to_name[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)
return -EINVAL;
p->p_type_val_to_name[typdatum->value - 1] = key;
}
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)
return -EINVAL;
p->p_user_val_to_name[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->isalias) {
if (!levdatum->level->sens ||
levdatum->level->sens > p->p_levels.nprim)
return -EINVAL;
p->p_sens_val_to_name[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->isalias) {
if (!catdatum->value || catdatum->value > p->p_cats.nprim)
return -EINVAL;
p->p_cat_val_to_name[catdatum->value - 1] = key;
}
return 0;
}
static int (*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,
};
/*
* Define the common val_to_name array and the class
* val_to_name and val_to_struct arrays in a policy
* database structure.
*
* Caller must clean up upon failure.
*/
static int policydb_index_classes(struct policydb *p)
{
int rc;
p->p_common_val_to_name =
kmalloc(p->p_commons.nprim * sizeof(char *), GFP_KERNEL);
if (!p->p_common_val_to_name) {
rc = -ENOMEM;
goto out;
}
rc = hashtab_map(p->p_commons.table, common_index, p);
if (rc)
goto out;
p->class_val_to_struct =
kmalloc(p->p_classes.nprim * sizeof(*(p->class_val_to_struct)), GFP_KERNEL);
if (!p->class_val_to_struct) {
rc = -ENOMEM;
goto out;
}
p->p_class_val_to_name =
kmalloc(p->p_classes.nprim * sizeof(char *), GFP_KERNEL);
if (!p->p_class_val_to_name) {
rc = -ENOMEM;
goto out;
}
rc = hashtab_map(p->p_classes.table, class_index, p);
out:
return rc;
}
#ifdef DEBUG_HASHES
static void symtab_hash_eval(struct symtab *s)
{
int i;
for (i = 0; i < SYM_NUM; i++) {
struct hashtab *h = s[i].table;
struct hashtab_info info;
hashtab_stat(h, &info);
printk(KERN_INFO "%s: %d entries and %d/%d buckets used, "
"longest chain length %d\n", symtab_name[i], h->nel,
info.slots_used, h->size, info.max_chain_len);
}
}
#endif
/*
* 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_others(struct policydb *p)
{
int i, rc = 0;
printk(KERN_INFO "security: %d users, %d roles, %d types, %d bools",
p->p_users.nprim, p->p_roles.nprim, p->p_types.nprim, p->p_bools.nprim);
if (selinux_mls_enabled)
printk(", %d sens, %d cats", p->p_levels.nprim,
p->p_cats.nprim);
printk("\n");
printk(KERN_INFO "security: %d classes, %d rules\n",
p->p_classes.nprim, p->te_avtab.nel);
#ifdef DEBUG_HASHES
avtab_hash_eval(&p->te_avtab, "rules");
symtab_hash_eval(p->symtab);
#endif
p->role_val_to_struct =
kmalloc(p->p_roles.nprim * sizeof(*(p->role_val_to_struct)),
GFP_KERNEL);
if (!p->role_val_to_struct) {
rc = -ENOMEM;
goto out;
}
p->user_val_to_struct =
kmalloc(p->p_users.nprim * sizeof(*(p->user_val_to_struct)),
GFP_KERNEL);
if (!p->user_val_to_struct) {
rc = -ENOMEM;
goto out;
}
if (cond_init_bool_indexes(p)) {
rc = -ENOMEM;
goto out;
}
for (i = SYM_ROLES; i < SYM_NUM; i++) {
p->sym_val_to_name[i] =
kmalloc(p->symtab[i].nprim * sizeof(char *), GFP_KERNEL);
if (!p->sym_val_to_name[i]) {
rc = -ENOMEM;
goto out;
}
rc = hashtab_map(p->symtab[i].table, index_f[i], p);
if (rc)
goto out;
}
out:
return rc;
}
/*
* 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);
comdatum = datum;
hashtab_map(comdatum->permissions.table, perm_destroy, NULL);
hashtab_destroy(comdatum->permissions.table);
kfree(datum);
return 0;
}
static int class_destroy(void *key, void *datum, void *p)
{
struct class_datum *cladatum;
struct constraint_node *constraint, *ctemp;
struct constraint_expr *e, *etmp;
kfree(key);
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) {
ebitmap_destroy(&e->names);
etmp = e;
e = e->next;
kfree(etmp);
}
ctemp = constraint;
constraint = constraint->next;
kfree(ctemp);
}
constraint = cladatum->validatetrans;
while (constraint) {
e = constraint->expr;
while (e) {
ebitmap_destroy(&e->names);
etmp = e;
e = e->next;
kfree(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);
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);
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);
levdatum = datum;
ebitmap_destroy(&levdatum->level->cat);
kfree(levdatum->level);
kfree(datum);
return 0;
}
static int cat_destroy(void *key, void *datum, void *p)
{
kfree(key);
kfree(datum);
return 0;
}
static int (*destroy_f[SYM_NUM]) (void *key, void *datum, void *datap) =
{
common_destroy,
class_destroy,
role_destroy,
type_destroy,
user_destroy,
cond_destroy_bool,
sens_destroy,
cat_destroy,
};
static void ocontext_destroy(struct ocontext *c, int i)
{
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);
}
/*
* Free any memory allocated by a policy database structure.
*/
void policydb_destroy(struct policydb *p)
{
struct ocontext *c, *ctmp;
struct genfs *g, *gtmp;
int i;
struct role_allow *ra, *lra = NULL;
struct role_trans *tr, *ltr = NULL;
struct range_trans *rt, *lrt = NULL;
for (i = 0; i < SYM_NUM; i++) {
hashtab_map(p->symtab[i].table, destroy_f[i], NULL);
hashtab_destroy(p->symtab[i].table);
}
for (i = 0; i < SYM_NUM; i++)
kfree(p->sym_val_to_name[i]);
kfree(p->class_val_to_struct);
kfree(p->role_val_to_struct);
kfree(p->user_val_to_struct);
avtab_destroy(&p->te_avtab);
for (i = 0; i < OCON_NUM; i++) {
c = p->ocontexts[i];
while (c) {
ctmp = c;
c = c->next;
ocontext_destroy(ctmp,i);
}
}
g = p->genfs;
while (g) {
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);
}
cond_policydb_destroy(p);
for (tr = p->role_tr; tr; tr = tr->next) {
if (ltr) kfree(ltr);
ltr = tr;
}
if (ltr) kfree(ltr);
for (ra = p->role_allow; ra; ra = ra -> next) {
if (lra) kfree(lra);
lra = ra;
}
if (lra) kfree(lra);
for (rt = p->range_tr; rt; rt = rt -> next) {
if (lrt) kfree(lrt);
lrt = rt;
}
if (lrt) kfree(lrt);
if (p->type_attr_map) {
for (i = 0; i < p->p_types.nprim; i++)
ebitmap_destroy(&p->type_attr_map[i]);
}
kfree(p->type_attr_map);
return;
}
/*
* 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;
int rc;
rc = sidtab_init(s);
if (rc) {
printk(KERN_ERR "security: out of memory on SID table init\n");
goto out;
}
head = p->ocontexts[OCON_ISID];
for (c = head; c; c = c->next) {
if (!c->context[0].user) {
printk(KERN_ERR "security: SID %s was never "
"defined.\n", c->u.name);
rc = -EINVAL;
goto out;
}
if (sidtab_insert(s, c->sid[0], &c->context[0])) {
printk(KERN_ERR "security: unable to load initial "
"SID %s.\n", c->u.name);
rc = -EINVAL;
goto out;
}
}
out:
return rc;
}
/*
* Return 1 if the fields in the security context
* structure `c' are valid. Return 0 otherwise.
*/
int policydb_context_isvalid(struct policydb *p, struct context *c)
{
struct role_datum *role;
struct user_datum *usrdatum;
if (!c->role || c->role > p->p_roles.nprim)
return 0;
if (!c->user || c->user > p->p_users.nprim)
return 0;
if (!c->type || c->type > p->p_types.nprim)
return 0;
if (c->role != OBJECT_R_VAL) {
/*
* Role must be authorized for the type.
*/
role = p->role_val_to_struct[c->role - 1];
if (!ebitmap_get_bit(&role->types,
c->type - 1))
/* role may not be associated with type */
return 0;
/*
* User must be authorized for the role.
*/
usrdatum = p->user_val_to_struct[c->user - 1];
if (!usrdatum)
return 0;
if (!ebitmap_get_bit(&usrdatum->roles,
c->role - 1))
/* user may not be associated with role */
return 0;
}
if (!mls_context_isvalid(p, c))
return 0;
return 1;
}
/*
* Read a MLS range structure from a policydb binary
* representation file.
*/
static int mls_read_range_helper(struct mls_range *r, void *fp)
{
__le32 buf[2];
u32 items;
int rc;
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto out;
items = le32_to_cpu(buf[0]);
if (items > ARRAY_SIZE(buf)) {
printk(KERN_ERR "security: mls: range overflow\n");
rc = -EINVAL;
goto out;
}
rc = next_entry(buf, fp, sizeof(u32) * items);
if (rc < 0) {
printk(KERN_ERR "security: 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) {
printk(KERN_ERR "security: mls: error reading low "
"categories\n");
goto out;
}
if (items > 1) {
rc = ebitmap_read(&r->level[1].cat, fp);
if (rc) {
printk(KERN_ERR "security: mls: error reading high "
"categories\n");
goto bad_high;
}
} else {
rc = ebitmap_cpy(&r->level[1].cat, &r->level[0].cat);
if (rc) {
printk(KERN_ERR "security: mls: out of memory\n");
goto bad_high;
}
}
rc = 0;
out:
return rc;
bad_high:
ebitmap_destroy(&r->level[0].cat);
goto out;
}
/*
* 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,
void *fp)
{
__le32 buf[3];
int rc;
rc = next_entry(buf, fp, sizeof buf);
if (rc < 0) {
printk(KERN_ERR "security: 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) {
if (mls_read_range_helper(&c->range, fp)) {
printk(KERN_ERR "security: error reading MLS range of "
"context\n");
rc = -EINVAL;
goto out;
}
}
if (!policydb_context_isvalid(p, c)) {
printk(KERN_ERR "security: invalid security context\n");
context_destroy(c);
rc = -EINVAL;
}
out:
return rc;
}
/*
* The following *_read functions are used to
* read the symbol data from a policy database
* binary representation file.
*/
static int perm_read(struct policydb *p, struct hashtab *h, void *fp)
{
char *key = NULL;
struct perm_datum *perdatum;
int rc;
__le32 buf[2];
u32 len;
perdatum = kmalloc(sizeof(*perdatum), GFP_KERNEL);
if (!perdatum) {
rc = -ENOMEM;
goto out;
}
memset(perdatum, 0, sizeof(*perdatum));
rc = next_entry(buf, fp, sizeof buf);
if (rc < 0)
goto bad;
len = le32_to_cpu(buf[0]);
perdatum->value = le32_to_cpu(buf[1]);
key = kmalloc(len + 1,GFP_KERNEL);
if (!key) {
rc = -ENOMEM;
goto bad;
}
rc = next_entry(key, fp, len);
if (rc < 0)
goto bad;
key[len] = 0;
rc = hashtab_insert(h, key, perdatum);
if (rc)
goto bad;
out:
return rc;
bad:
perm_destroy(key, perdatum, NULL);
goto out;
}
static int common_read(struct policydb *p, struct hashtab *h, void *fp)
{
char *key = NULL;
struct common_datum *comdatum;
__le32 buf[4];
u32 len, nel;
int i, rc;
comdatum = kmalloc(sizeof(*comdatum), GFP_KERNEL);
if (!comdatum) {
rc = -ENOMEM;
goto out;
}
memset(comdatum, 0, sizeof(*comdatum));
rc = next_entry(buf, fp, sizeof buf);
if (rc < 0)
goto bad;
len = le32_to_cpu(buf[0]);
comdatum->value = le32_to_cpu(buf[1]);
rc = symtab_init(&comdatum->permissions, PERM_SYMTAB_SIZE);
if (rc)
goto bad;
comdatum->permissions.nprim = le32_to_cpu(buf[2]);
nel = le32_to_cpu(buf[3]);
key = kmalloc(len + 1,GFP_KERNEL);
if (!key) {
rc = -ENOMEM;
goto bad;
}
rc = next_entry(key, fp, len);
if (rc < 0)
goto bad;
key[len] = 0;
for (i = 0; i < nel; i++) {
rc = perm_read(p, comdatum->permissions.table, fp);
if (rc)
goto bad;
}
rc = hashtab_insert(h, key, comdatum);
if (rc)
goto bad;
out:
return rc;
bad:
common_destroy(key, comdatum, NULL);
goto out;
}
static int read_cons_helper(struct constraint_node **nodep, int ncons,
int allowxtarget, void *fp)
{
struct constraint_node *c, *lc;
struct constraint_expr *e, *le;
__le32 buf[3];
u32 nexpr;
int rc, i, j, depth;
lc = NULL;
for (i = 0; i < ncons; i++) {
c = kmalloc(sizeof(*c), GFP_KERNEL);
if (!c)
return -ENOMEM;
memset(c, 0, sizeof(*c));
if (lc) {
lc->next = c;
} else {
*nodep = c;
}
rc = next_entry(buf, fp, (sizeof(u32) * 2));
if (rc < 0)
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 = kmalloc(sizeof(*e), GFP_KERNEL);
if (!e)
return -ENOMEM;
memset(e, 0, sizeof(*e));
if (le) {
le->next = e;
} else {
c->expr = e;
}
rc = next_entry(buf, fp, (sizeof(u32) * 3));
if (rc < 0)
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++;
if (ebitmap_read(&e->names, fp))
return -EINVAL;
break;
default:
return -EINVAL;
}
le = e;
}
if (depth != 0)
return -EINVAL;
lc = c;
}
return 0;
}
static int class_read(struct policydb *p, struct hashtab *h, void *fp)
{
char *key = NULL;
struct class_datum *cladatum;
__le32 buf[6];
u32 len, len2, ncons, nel;
int i, rc;
cladatum = kmalloc(sizeof(*cladatum), GFP_KERNEL);
if (!cladatum) {
rc = -ENOMEM;
goto out;
}
memset(cladatum, 0, sizeof(*cladatum));
rc = next_entry(buf, fp, sizeof(u32)*6);
if (rc < 0)
goto bad;
len = le32_to_cpu(buf[0]);
len2 = le32_to_cpu(buf[1]);
cladatum->value = le32_to_cpu(buf[2]);
rc = symtab_init(&cladatum->permissions, PERM_SYMTAB_SIZE);
if (rc)
goto bad;
cladatum->permissions.nprim = le32_to_cpu(buf[3]);
nel = le32_to_cpu(buf[4]);
ncons = le32_to_cpu(buf[5]);
key = kmalloc(len + 1,GFP_KERNEL);
if (!key) {
rc = -ENOMEM;
goto bad;
}
rc = next_entry(key, fp, len);
if (rc < 0)
goto bad;
key[len] = 0;
if (len2) {
cladatum->comkey = kmalloc(len2 + 1,GFP_KERNEL);
if (!cladatum->comkey) {
rc = -ENOMEM;
goto bad;
}
rc = next_entry(cladatum->comkey, fp, len2);
if (rc < 0)
goto bad;
cladatum->comkey[len2] = 0;
cladatum->comdatum = hashtab_search(p->p_commons.table,
cladatum->comkey);
if (!cladatum->comdatum) {
printk(KERN_ERR "security: unknown common %s\n",
cladatum->comkey);
rc = -EINVAL;
goto bad;
}
}
for (i = 0; i < nel; i++) {
rc = perm_read(p, cladatum->permissions.table, fp);
if (rc)
goto bad;
}
rc = read_cons_helper(&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 < 0)
goto bad;
ncons = le32_to_cpu(buf[0]);
rc = read_cons_helper(&cladatum->validatetrans, ncons, 1, fp);
if (rc)
goto bad;
}
rc = hashtab_insert(h, key, cladatum);
if (rc)
goto bad;
rc = 0;
out:
return rc;
bad:
class_destroy(key, cladatum, NULL);
goto out;
}
static int role_read(struct policydb *p, struct hashtab *h, void *fp)
{
char *key = NULL;
struct role_datum *role;
int rc;
__le32 buf[2];
u32 len;
role = kmalloc(sizeof(*role), GFP_KERNEL);
if (!role) {
rc = -ENOMEM;
goto out;
}
memset(role, 0, sizeof(*role));
rc = next_entry(buf, fp, sizeof buf);
if (rc < 0)
goto bad;
len = le32_to_cpu(buf[0]);
role->value = le32_to_cpu(buf[1]);
key = kmalloc(len + 1,GFP_KERNEL);
if (!key) {
rc = -ENOMEM;
goto bad;
}
rc = next_entry(key, fp, len);
if (rc < 0)
goto bad;
key[len] = 0;
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) {
if (role->value != OBJECT_R_VAL) {
printk(KERN_ERR "Role %s has wrong value %d\n",
OBJECT_R, role->value);
rc = -EINVAL;
goto bad;
}
rc = 0;
goto bad;
}
rc = hashtab_insert(h, key, role);
if (rc)
goto bad;
out:
return rc;
bad:
role_destroy(key, role, NULL);
goto out;
}
static int type_read(struct policydb *p, struct hashtab *h, void *fp)
{
char *key = NULL;
struct type_datum *typdatum;
int rc;
__le32 buf[3];
u32 len;
typdatum = kmalloc(sizeof(*typdatum),GFP_KERNEL);
if (!typdatum) {
rc = -ENOMEM;
return rc;
}
memset(typdatum, 0, sizeof(*typdatum));
rc = next_entry(buf, fp, sizeof buf);
if (rc < 0)
goto bad;
len = le32_to_cpu(buf[0]);
typdatum->value = le32_to_cpu(buf[1]);
typdatum->primary = le32_to_cpu(buf[2]);
key = kmalloc(len + 1,GFP_KERNEL);
if (!key) {
rc = -ENOMEM;
goto bad;
}
rc = next_entry(key, fp, len);
if (rc < 0)
goto bad;
key[len] = 0;
rc = hashtab_insert(h, key, typdatum);
if (rc)
goto bad;
out:
return rc;
bad:
type_destroy(key, typdatum, NULL);
goto out;
}
/*
* Read a MLS level structure from a policydb binary
* representation file.
*/
static int mls_read_level(struct mls_level *lp, void *fp)
{
__le32 buf[1];
int rc;
memset(lp, 0, sizeof(*lp));
rc = next_entry(buf, fp, sizeof buf);
if (rc < 0) {
printk(KERN_ERR "security: mls: truncated level\n");
goto bad;
}
lp->sens = le32_to_cpu(buf[0]);
if (ebitmap_read(&lp->cat, fp)) {
printk(KERN_ERR "security: mls: error reading level "
"categories\n");
goto bad;
}
return 0;
bad:
return -EINVAL;
}
static int user_read(struct policydb *p, struct hashtab *h, void *fp)
{
char *key = NULL;
struct user_datum *usrdatum;
int rc;
__le32 buf[2];
u32 len;
usrdatum = kmalloc(sizeof(*usrdatum), GFP_KERNEL);
if (!usrdatum) {
rc = -ENOMEM;
goto out;
}
memset(usrdatum, 0, sizeof(*usrdatum));
rc = next_entry(buf, fp, sizeof buf);
if (rc < 0)
goto bad;
len = le32_to_cpu(buf[0]);
usrdatum->value = le32_to_cpu(buf[1]);
key = kmalloc(len + 1,GFP_KERNEL);
if (!key) {
rc = -ENOMEM;
goto bad;
}
rc = next_entry(key, fp, len);
if (rc < 0)
goto bad;
key[len] = 0;
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 = hashtab_insert(h, key, usrdatum);
if (rc)
goto bad;
out:
return rc;
bad:
user_destroy(key, usrdatum, NULL);
goto out;
}
static int sens_read(struct policydb *p, struct hashtab *h, void *fp)
{
char *key = NULL;
struct level_datum *levdatum;
int rc;
__le32 buf[2];
u32 len;
levdatum = kmalloc(sizeof(*levdatum), GFP_ATOMIC);
if (!levdatum) {
rc = -ENOMEM;
goto out;
}
memset(levdatum, 0, sizeof(*levdatum));
rc = next_entry(buf, fp, sizeof buf);
if (rc < 0)
goto bad;
len = le32_to_cpu(buf[0]);
levdatum->isalias = le32_to_cpu(buf[1]);
key = kmalloc(len + 1,GFP_ATOMIC);
if (!key) {
rc = -ENOMEM;
goto bad;
}
rc = next_entry(key, fp, len);
if (rc < 0)
goto bad;
key[len] = 0;
levdatum->level = kmalloc(sizeof(struct mls_level), GFP_ATOMIC);
if (!levdatum->level) {
rc = -ENOMEM;
goto bad;
}
if (mls_read_level(levdatum->level, fp)) {
rc = -EINVAL;
goto bad;
}
rc = hashtab_insert(h, key, levdatum);
if (rc)
goto bad;
out:
return rc;
bad:
sens_destroy(key, levdatum, NULL);
goto out;
}
static int cat_read(struct policydb *p, struct hashtab *h, void *fp)
{
char *key = NULL;
struct cat_datum *catdatum;
int rc;
__le32 buf[3];
u32 len;
catdatum = kmalloc(sizeof(*catdatum), GFP_ATOMIC);
if (!catdatum) {
rc = -ENOMEM;
goto out;
}
memset(catdatum, 0, sizeof(*catdatum));
rc = next_entry(buf, fp, sizeof buf);
if (rc < 0)
goto bad;
len = le32_to_cpu(buf[0]);
catdatum->value = le32_to_cpu(buf[1]);
catdatum->isalias = le32_to_cpu(buf[2]);
key = kmalloc(len + 1,GFP_ATOMIC);
if (!key) {
rc = -ENOMEM;
goto bad;
}
rc = next_entry(key, fp, len);
if (rc < 0)
goto bad;
key[len] = 0;
rc = hashtab_insert(h, key, catdatum);
if (rc)
goto bad;
out:
return rc;
bad:
cat_destroy(key, catdatum, NULL);
goto out;
}
static int (*read_f[SYM_NUM]) (struct policydb *p, struct hashtab *h, void *fp) =
{
common_read,
class_read,
role_read,
type_read,
user_read,
cond_read_bool,
sens_read,
cat_read,
};
extern int ss_initialized;
/*
* Read the configuration data from a policy database binary
* representation file into a policy database structure.
*/
int policydb_read(struct policydb *p, void *fp)
{
struct role_allow *ra, *lra;
struct role_trans *tr, *ltr;
struct ocontext *l, *c, *newc;
struct genfs *genfs_p, *genfs, *newgenfs;
int i, j, rc;
__le32 buf[8];
u32 len, len2, config, nprim, nel, nel2;
char *policydb_str;
struct policydb_compat_info *info;
struct range_trans *rt, *lrt;
config = 0;
rc = policydb_init(p);
if (rc)
goto out;
/* Read the magic number and string length. */
rc = next_entry(buf, fp, sizeof(u32)* 2);
if (rc < 0)
goto bad;
if (le32_to_cpu(buf[0]) != POLICYDB_MAGIC) {
printk(KERN_ERR "security: policydb magic number 0x%x does "
"not match expected magic number 0x%x\n",
le32_to_cpu(buf[0]), POLICYDB_MAGIC);
goto bad;
}
len = le32_to_cpu(buf[1]);
if (len != strlen(POLICYDB_STRING)) {
printk(KERN_ERR "security: policydb string length %d does not "
"match expected length %Zu\n",
len, strlen(POLICYDB_STRING));
goto bad;
}
policydb_str = kmalloc(len + 1,GFP_KERNEL);
if (!policydb_str) {
printk(KERN_ERR "security: unable to allocate memory for policydb "
"string of length %d\n", len);
rc = -ENOMEM;
goto bad;
}
rc = next_entry(policydb_str, fp, len);
if (rc < 0) {
printk(KERN_ERR "security: truncated policydb string identifier\n");
kfree(policydb_str);
goto bad;
}
policydb_str[len] = 0;
if (strcmp(policydb_str, POLICYDB_STRING)) {
printk(KERN_ERR "security: 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, config, and table sizes. */
rc = next_entry(buf, fp, sizeof(u32)*4);
if (rc < 0)
goto bad;
p->policyvers = le32_to_cpu(buf[0]);
if (p->policyvers < POLICYDB_VERSION_MIN ||
p->policyvers > POLICYDB_VERSION_MAX) {
printk(KERN_ERR "security: 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)) {
if (ss_initialized && !selinux_mls_enabled) {
printk(KERN_ERR "Cannot switch between non-MLS and MLS "
"policies\n");
goto bad;
}
selinux_mls_enabled = 1;
config |= POLICYDB_CONFIG_MLS;
if (p->policyvers < POLICYDB_VERSION_MLS) {
printk(KERN_ERR "security policydb version %d (MLS) "
"not backwards compatible\n", p->policyvers);
goto bad;
}
} else {
if (ss_initialized && selinux_mls_enabled) {
printk(KERN_ERR "Cannot switch between MLS and non-MLS "
"policies\n");
goto bad;
}
}
info = policydb_lookup_compat(p->policyvers);
if (!info) {
printk(KERN_ERR "security: unable to find policy compat info "
"for version %d\n", p->policyvers);
goto bad;
}
if (le32_to_cpu(buf[2]) != info->sym_num ||
le32_to_cpu(buf[3]) != info->ocon_num) {
printk(KERN_ERR "security: 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 < 0)
goto bad;
nprim = le32_to_cpu(buf[0]);
nel = le32_to_cpu(buf[1]);
for (j = 0; j < nel; j++) {
rc = read_f[i](p, p->symtab[i].table, fp);
if (rc)
goto bad;
}
p->symtab[i].nprim = nprim;
}
rc = avtab_read(&p->te_avtab, fp, p->policyvers);
if (rc)
goto bad;
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 < 0)
goto bad;
nel = le32_to_cpu(buf[0]);
ltr = NULL;
for (i = 0; i < nel; i++) {
tr = kmalloc(sizeof(*tr), GFP_KERNEL);
if (!tr) {
rc = -ENOMEM;
goto bad;
}
memset(tr, 0, sizeof(*tr));
if (ltr) {
ltr->next = tr;
} else {
p->role_tr = tr;
}
rc = next_entry(buf, fp, sizeof(u32)*3);
if (rc < 0)
goto bad;
tr->role = le32_to_cpu(buf[0]);
tr->type = le32_to_cpu(buf[1]);
tr->new_role = le32_to_cpu(buf[2]);
ltr = tr;
}
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad;
nel = le32_to_cpu(buf[0]);
lra = NULL;
for (i = 0; i < nel; i++) {
ra = kmalloc(sizeof(*ra), GFP_KERNEL);
if (!ra) {
rc = -ENOMEM;
goto bad;
}
memset(ra, 0, sizeof(*ra));
if (lra) {
lra->next = ra;
} else {
p->role_allow = ra;
}
rc = next_entry(buf, fp, sizeof(u32)*2);
if (rc < 0)
goto bad;
ra->role = le32_to_cpu(buf[0]);
ra->new_role = le32_to_cpu(buf[1]);
lra = ra;
}
rc = policydb_index_classes(p);
if (rc)
goto bad;
rc = policydb_index_others(p);
if (rc)
goto bad;
for (i = 0; i < info->ocon_num; i++) {
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad;
nel = le32_to_cpu(buf[0]);
l = NULL;
for (j = 0; j < nel; j++) {
c = kmalloc(sizeof(*c), GFP_KERNEL);
if (!c) {
rc = -ENOMEM;
goto bad;
}
memset(c, 0, sizeof(*c));
if (l) {
l->next = c;
} else {
p->ocontexts[i] = c;
}
l = c;
rc = -EINVAL;
switch (i) {
case OCON_ISID:
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad;
c->sid[0] = le32_to_cpu(buf[0]);
rc = context_read_and_validate(&c->context[0], p, fp);
if (rc)
goto bad;
break;
case OCON_FS:
case OCON_NETIF:
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad;
len = le32_to_cpu(buf[0]);
c->u.name = kmalloc(len + 1,GFP_KERNEL);
if (!c->u.name) {
rc = -ENOMEM;
goto bad;
}
rc = next_entry(c->u.name, fp, len);
if (rc < 0)
goto bad;
c->u.name[len] = 0;
rc = context_read_and_validate(&c->context[0], p, fp);
if (rc)
goto bad;
rc = context_read_and_validate(&c->context[1], p, fp);
if (rc)
goto bad;
break;
case OCON_PORT:
rc = next_entry(buf, fp, sizeof(u32)*3);
if (rc < 0)
goto bad;
c->u.port.protocol = le32_to_cpu(buf[0]);
c->u.port.low_port = le32_to_cpu(buf[1]);
c->u.port.high_port = le32_to_cpu(buf[2]);
rc = context_read_and_validate(&c->context[0], p, fp);
if (rc)
goto bad;
break;
case OCON_NODE:
rc = next_entry(buf, fp, sizeof(u32)* 2);
if (rc < 0)
goto bad;
c->u.node.addr = le32_to_cpu(buf[0]);
c->u.node.mask = le32_to_cpu(buf[1]);
rc = context_read_and_validate(&c->context[0], p, fp);
if (rc)
goto bad;
break;
case OCON_FSUSE:
rc = next_entry(buf, fp, sizeof(u32)*2);
if (rc < 0)
goto bad;
c->v.behavior = le32_to_cpu(buf[0]);
if (c->v.behavior > SECURITY_FS_USE_NONE)
goto bad;
len = le32_to_cpu(buf[1]);
c->u.name = kmalloc(len + 1,GFP_KERNEL);
if (!c->u.name) {
rc = -ENOMEM;
goto bad;
}
rc = next_entry(c->u.name, fp, len);
if (rc < 0)
goto bad;
c->u.name[len] = 0;
rc = context_read_and_validate(&c->context[0], p, fp);
if (rc)
goto bad;
break;
case OCON_NODE6: {
int k;
rc = next_entry(buf, fp, sizeof(u32) * 8);
if (rc < 0)
goto bad;
for (k = 0; k < 4; k++)
c->u.node6.addr[k] = le32_to_cpu(buf[k]);
for (k = 0; k < 4; k++)
c->u.node6.mask[k] = le32_to_cpu(buf[k+4]);
if (context_read_and_validate(&c->context[0], p, fp))
goto bad;
break;
}
}
}
}
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad;
nel = le32_to_cpu(buf[0]);
genfs_p = NULL;
rc = -EINVAL;
for (i = 0; i < nel; i++) {
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad;
len = le32_to_cpu(buf[0]);
newgenfs = kmalloc(sizeof(*newgenfs), GFP_KERNEL);
if (!newgenfs) {
rc = -ENOMEM;
goto bad;
}
memset(newgenfs, 0, sizeof(*newgenfs));
newgenfs->fstype = kmalloc(len + 1,GFP_KERNEL);
if (!newgenfs->fstype) {
rc = -ENOMEM;
kfree(newgenfs);
goto bad;
}
rc = next_entry(newgenfs->fstype, fp, len);
if (rc < 0) {
kfree(newgenfs->fstype);
kfree(newgenfs);
goto bad;
}
newgenfs->fstype[len] = 0;
for (genfs_p = NULL, genfs = p->genfs; genfs;
genfs_p = genfs, genfs = genfs->next) {
if (strcmp(newgenfs->fstype, genfs->fstype) == 0) {
printk(KERN_ERR "security: dup genfs "
"fstype %s\n", newgenfs->fstype);
kfree(newgenfs->fstype);
kfree(newgenfs);
goto bad;
}
if (strcmp(newgenfs->fstype, genfs->fstype) < 0)
break;
}
newgenfs->next = genfs;
if (genfs_p)
genfs_p->next = newgenfs;
else
p->genfs = newgenfs;
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad;
nel2 = le32_to_cpu(buf[0]);
for (j = 0; j < nel2; j++) {
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad;
len = le32_to_cpu(buf[0]);
newc = kmalloc(sizeof(*newc), GFP_KERNEL);
if (!newc) {
rc = -ENOMEM;
goto bad;
}
memset(newc, 0, sizeof(*newc));
newc->u.name = kmalloc(len + 1,GFP_KERNEL);
if (!newc->u.name) {
rc = -ENOMEM;
goto bad_newc;
}
rc = next_entry(newc->u.name, fp, len);
if (rc < 0)
goto bad_newc;
newc->u.name[len] = 0;
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad_newc;
newc->v.sclass = le32_to_cpu(buf[0]);
if (context_read_and_validate(&newc->context[0], p, fp))
goto bad_newc;
for (l = NULL, c = newgenfs->head; c;
l = c, c = c->next) {
if (!strcmp(newc->u.name, c->u.name) &&
(!c->v.sclass || !newc->v.sclass ||
newc->v.sclass == c->v.sclass)) {
printk(KERN_ERR "security: dup genfs "
"entry (%s,%s)\n",
newgenfs->fstype, c->u.name);
goto bad_newc;
}
len = strlen(newc->u.name);
len2 = strlen(c->u.name);
if (len > len2)
break;
}
newc->next = c;
if (l)
l->next = newc;
else
newgenfs->head = newc;
}
}
if (p->policyvers >= POLICYDB_VERSION_MLS) {
rc = next_entry(buf, fp, sizeof(u32));
if (rc < 0)
goto bad;
nel = le32_to_cpu(buf[0]);
lrt = NULL;
for (i = 0; i < nel; i++) {
rt = kmalloc(sizeof(*rt), GFP_KERNEL);
if (!rt) {
rc = -ENOMEM;
goto bad;
}
memset(rt, 0, sizeof(*rt));
if (lrt)
lrt->next = rt;
else
p->range_tr = rt;
rc = next_entry(buf, fp, (sizeof(u32) * 2));
if (rc < 0)
goto bad;
rt->dom = le32_to_cpu(buf[0]);
rt->type = le32_to_cpu(buf[1]);
rc = mls_read_range_helper(&rt->range, fp);
if (rc)
goto bad;
lrt = rt;
}
}
p->type_attr_map = kmalloc(p->p_types.nprim*sizeof(struct ebitmap), GFP_KERNEL);
if (!p->type_attr_map)
goto bad;
for (i = 0; i < p->p_types.nprim; i++) {
ebitmap_init(&p->type_attr_map[i]);
if (p->policyvers >= POLICYDB_VERSION_AVTAB) {
if (ebitmap_read(&p->type_attr_map[i], fp))
goto bad;
}
/* add the type itself as the degenerate case */
if (ebitmap_set_bit(&p->type_attr_map[i], i, 1))
goto bad;
}
rc = 0;
out:
return rc;
bad_newc:
ocontext_destroy(newc,OCON_FSUSE);
bad:
if (!rc)
rc = -EINVAL;
policydb_destroy(p);
goto out;
}