Merge tag 'selinux-pr-20200803' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux

Pull selinux updates from Paul Moore:
 "Beyond the usual smattering of bug fixes, we've got three small
  improvements worth highlighting:

   - improved SELinux policy symbol table performance due to a reworking
     of the insert and search functions

   - allow reading of SELinux labels before the policy is loaded,
     allowing for some more "exotic" initramfs approaches

   - improved checking an error reporting about process
     class/permissions during SELinux policy load"

* tag 'selinux-pr-20200803' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
  selinux: complete the inlining of hashtab functions
  selinux: prepare for inlining of hashtab functions
  selinux: specialize symtab insert and search functions
  selinux: Fix spelling mistakes in the comments
  selinux: fixed a checkpatch warning with the sizeof macro
  selinux: log error messages on required process class / permissions
  scripts/selinux/mdp: fix initial SID handling
  selinux: allow reading labels before policy is loaded

scripts/selinux/mdp/mdp.c

@@ -67,8 +67,14 @@ int main(int argc, char *argv[])
 
 	initial_sid_to_string_len = sizeof(initial_sid_to_string) / sizeof (char *);
 	/* print out the sids */
-	for (i = 1; i < initial_sid_to_string_len; i++)
-		fprintf(fout, "sid %s\n", initial_sid_to_string[i]);
+	for (i = 1; i < initial_sid_to_string_len; i++) {
+		const char *name = initial_sid_to_string[i];
+
+		if (name)
+			fprintf(fout, "sid %s\n", name);
+		else
+			fprintf(fout, "sid unused%d\n", i);
+	}
 	fprintf(fout, "\n");
 
 	/* print out the class permissions */
@@ -126,9 +132,16 @@ int main(int argc, char *argv[])
 #define OBJUSERROLETYPE "user_u:object_r:base_t"
 
 	/* default sids */
-	for (i = 1; i < initial_sid_to_string_len; i++)
-		fprintf(fout, "sid %s " SUBJUSERROLETYPE "%s\n",
-			initial_sid_to_string[i], mls ? ":" SYSTEMLOW : "");
+	for (i = 1; i < initial_sid_to_string_len; i++) {
+		const char *name = initial_sid_to_string[i];
+
+		if (name)
+			fprintf(fout, "sid %s ", name);
+		else
+			fprintf(fout, "sid unused%d\n", i);
+		fprintf(fout, SUBJUSERROLETYPE "%s\n",
+			mls ? ":" SYSTEMLOW : "");
+	}
 	fprintf(fout, "\n");
 
 #define FS_USE(behavior, fstype)			    \

security/selinux/hooks.c

@@ -3332,7 +3332,12 @@ static int selinux_inode_getsecurity(struct inode *inode, const char *name, void
 	char *context = NULL;
 	struct inode_security_struct *isec;
 
-	if (strcmp(name, XATTR_SELINUX_SUFFIX))
+	/*
+	 * If we're not initialized yet, then we can't validate contexts, so
+	 * just let vfs_getxattr fall back to using the on-disk xattr.
+	 */
+	if (!selinux_initialized(&selinux_state) ||
+	    strcmp(name, XATTR_SELINUX_SUFFIX))
 		return -EOPNOTSUPP;
 
 	/*

security/selinux/netif.c

@@ -124,7 +124,7 @@ static void sel_netif_destroy(struct sel_netif *netif)
  * @sid: interface SID
  *
  * Description:
- * This function determines the SID of a network interface by quering the
+ * This function determines the SID of a network interface by querying the
  * security policy.  The result is added to the network interface table to
  * speedup future queries.  Returns zero on success, negative values on
  * failure.

security/selinux/netnode.c

@@ -181,7 +181,7 @@ static void sel_netnode_insert(struct sel_netnode *node)
  * @sid: node SID
  *
  * Description:
- * This function determines the SID of a network address by quering the
+ * This function determines the SID of a network address by querying the
  * security policy.  The result is added to the network address table to
  * speedup future queries.  Returns zero on success, negative values on
  * failure.

security/selinux/netport.c

@@ -130,7 +130,7 @@ static void sel_netport_insert(struct sel_netport *port)
  * @sid: port SID
  *
  * Description:
- * This function determines the SID of a network port by quering the security
+ * This function determines the SID of a network port by querying the security
  * policy.  The result is added to the network port table to speedup future
  * queries.  Returns zero on success, negative values on failure.
  *

security/selinux/ss/conditional.c

@@ -203,7 +203,7 @@ static int bool_isvalid(struct cond_bool_datum *b)
 	return 1;
 }
 
-int cond_read_bool(struct policydb *p, struct hashtab *h, void *fp)
+int cond_read_bool(struct policydb *p, struct symtab *s, void *fp)
 {
 	char *key = NULL;
 	struct cond_bool_datum *booldatum;
@@ -215,7 +215,7 @@ int cond_read_bool(struct policydb *p, struct hashtab *h, void *fp)
 	if (!booldatum)
 		return -ENOMEM;
 
-	rc = next_entry(buf, fp, sizeof buf);
+	rc = next_entry(buf, fp, sizeof(buf));
 	if (rc)
 		goto err;
 
@@ -238,7 +238,7 @@ int cond_read_bool(struct policydb *p, struct hashtab *h, void *fp)
 	if (rc)
 		goto err;
 	key[len] = '\0';
-	rc = hashtab_insert(h, key, booldatum);
+	rc = symtab_insert(s, key, booldatum);
 	if (rc)
 		goto err;
 
@@ -416,7 +416,7 @@ int cond_read_list(struct policydb *p, void *fp)
 	u32 i, len;
 	int rc;
 
-	rc = next_entry(buf, fp, sizeof buf);
+	rc = next_entry(buf, fp, sizeof(buf));
 	if (rc)
 		return rc;
 

security/selinux/ss/conditional.h

@@ -69,7 +69,7 @@ int cond_destroy_bool(void *key, void *datum, void *p);
 
 int cond_index_bool(void *key, void *datum, void *datap);
 
-int cond_read_bool(struct policydb *p, struct hashtab *h, void *fp);
+int cond_read_bool(struct policydb *p, struct symtab *s, void *fp);
 int cond_read_list(struct policydb *p, void *fp);
 int cond_write_bool(void *key, void *datum, void *ptr);
 int cond_write_list(struct policydb *p, void *fp);

security/selinux/ss/hashtab.c

@@ -7,7 +7,6 @@
 #include <linux/kernel.h>
 #include <linux/slab.h>
 #include <linux/errno.h>
-#include <linux/sched.h>
 #include "hashtab.h"
 
 static struct kmem_cache *hashtab_node_cachep;
@@ -29,16 +28,10 @@ static u32 hashtab_compute_size(u32 nel)
 	return nel == 0 ? 0 : roundup_pow_of_two(nel);
 }
 
-int hashtab_init(struct hashtab *h,
-		 u32 (*hash_value)(struct hashtab *h, const void *key),
-		 int (*keycmp)(struct hashtab *h, const void *key1,
-			       const void *key2),
-		 u32 nel_hint)
+int hashtab_init(struct hashtab *h, u32 nel_hint)
 {
 	h->size = hashtab_compute_size(nel_hint);
 	h->nel = 0;
-	h->hash_value = hash_value;
-	h->keycmp = keycmp;
 	if (!h->size)
 		return 0;
 
@@ -46,63 +39,23 @@ int hashtab_init(struct hashtab *h,
 	return h->htable ? 0 : -ENOMEM;
 }
 
-int hashtab_insert(struct hashtab *h, void *key, void *datum)
+int __hashtab_insert(struct hashtab *h, struct hashtab_node **dst,
+		     void *key, void *datum)
 {
-	u32 hvalue;
-	struct hashtab_node *prev, *cur, *newnode;
-
-	cond_resched();
-
-	if (!h->size || h->nel == HASHTAB_MAX_NODES)
-		return -EINVAL;
-
-	hvalue = h->hash_value(h, key);
-	prev = NULL;
-	cur = h->htable[hvalue];
-	while (cur && h->keycmp(h, key, cur->key) > 0) {
-		prev = cur;
-		cur = cur->next;
-	}
-
-	if (cur && (h->keycmp(h, key, cur->key) == 0))
-		return -EEXIST;
+	struct hashtab_node *newnode;
 
 	newnode = kmem_cache_zalloc(hashtab_node_cachep, GFP_KERNEL);
 	if (!newnode)
 		return -ENOMEM;
 	newnode->key = key;
 	newnode->datum = datum;
-	if (prev) {
-		newnode->next = prev->next;
-		prev->next = newnode;
-	} else {
-		newnode->next = h->htable[hvalue];
-		h->htable[hvalue] = newnode;
-	}
+	newnode->next = *dst;
+	*dst = newnode;
 
 	h->nel++;
 	return 0;
 }
 
-void *hashtab_search(struct hashtab *h, const void *key)
-{
-	u32 hvalue;
-	struct hashtab_node *cur;
-
-	if (!h->size)
-		return NULL;
-
-	hvalue = h->hash_value(h, key);
-	cur = h->htable[hvalue];
-	while (cur && h->keycmp(h, key, cur->key) > 0)
-		cur = cur->next;
-
-	if (!cur || (h->keycmp(h, key, cur->key) != 0))
-		return NULL;
-
-	return cur->datum;
-}
-
 void hashtab_destroy(struct hashtab *h)
 {
 	u32 i;

security/selinux/ss/hashtab.h

@@ -11,7 +11,17 @@
 #ifndef _SS_HASHTAB_H_
 #define _SS_HASHTAB_H_
 
-#define HASHTAB_MAX_NODES	0xffffffff
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+
+#define HASHTAB_MAX_NODES	U32_MAX
+
+struct hashtab_key_params {
+	u32 (*hash)(const void *key);	/* hash function */
+	int (*cmp)(const void *key1, const void *key2);
+					/* key comparison function */
+};
 
 struct hashtab_node {
 	void *key;
@@ -23,10 +33,6 @@ struct hashtab {
 	struct hashtab_node **htable;	/* hash table */
 	u32 size;			/* number of slots in hash table */
 	u32 nel;			/* number of elements in hash table */
-	u32 (*hash_value)(struct hashtab *h, const void *key);
-					/* hash function */
-	int (*keycmp)(struct hashtab *h, const void *key1, const void *key2);
-					/* key comparison function */
 };
 
 struct hashtab_info {
@@ -39,11 +45,10 @@ struct hashtab_info {
  *
  * Returns -ENOMEM if insufficient space is available or 0 otherwise.
  */
-int hashtab_init(struct hashtab *h,
-		 u32 (*hash_value)(struct hashtab *h, const void *key),
-		 int (*keycmp)(struct hashtab *h, const void *key1,
-			       const void *key2),
-		 u32 nel_hint);
+int hashtab_init(struct hashtab *h, u32 nel_hint);
+
+int __hashtab_insert(struct hashtab *h, struct hashtab_node **dst,
+		     void *key, void *datum);
 
 /*
  * Inserts the specified (key, datum) pair into the specified hash table.
@@ -53,7 +58,34 @@ int hashtab_init(struct hashtab *h,
  * -EINVAL for general errors or
   0 otherwise.
  */
-int hashtab_insert(struct hashtab *h, void *k, void *d);
+static inline int hashtab_insert(struct hashtab *h, void *key, void *datum,
+				 struct hashtab_key_params key_params)
+{
+	u32 hvalue;
+	struct hashtab_node *prev, *cur;
+
+	cond_resched();
+
+	if (!h->size || h->nel == HASHTAB_MAX_NODES)
+		return -EINVAL;
+
+	hvalue = key_params.hash(key) & (h->size - 1);
+	prev = NULL;
+	cur = h->htable[hvalue];
+	while (cur) {
+		int cmp = key_params.cmp(key, cur->key);
+
+		if (cmp == 0)
+			return -EEXIST;
+		if (cmp < 0)
+			break;
+		prev = cur;
+		cur = cur->next;
+	}
+
+	return __hashtab_insert(h, prev ? &prev->next : &h->htable[hvalue],
+				key, datum);
+}
 
 /*
  * Searches for the entry with the specified key in the hash table.
@@ -61,7 +93,28 @@ int hashtab_insert(struct hashtab *h, void *k, void *d);
  * Returns NULL if no entry has the specified key or
  * the datum of the entry otherwise.
  */
-void *hashtab_search(struct hashtab *h, const void *k);
+static inline void *hashtab_search(struct hashtab *h, const void *key,
+				   struct hashtab_key_params key_params)
+{
+	u32 hvalue;
+	struct hashtab_node *cur;
+
+	if (!h->size)
+		return NULL;
+
+	hvalue = key_params.hash(key) & (h->size - 1);
+	cur = h->htable[hvalue];
+	while (cur) {
+		int cmp = key_params.cmp(key, cur->key);
+
+		if (cmp == 0)
+			return cur->datum;
+		if (cmp < 0)
+			break;
+		cur = cur->next;
+	}
+	return NULL;
+}
 
 /*
  * Destroys the specified hash table.

security/selinux/ss/mls.c

@@ -165,7 +165,7 @@ int mls_level_isvalid(struct policydb *p, struct mls_level *l)
 
 	if (!l->sens || l->sens > p->p_levels.nprim)
 		return 0;
-	levdatum = hashtab_search(&p->p_levels.table,
+	levdatum = symtab_search(&p->p_levels,
 				 sym_name(p, SYM_LEVELS, l->sens - 1));
 	if (!levdatum)
 		return 0;
@@ -293,7 +293,7 @@ int mls_context_to_sid(struct policydb *pol,
 			*(next_cat++) = '\0';
 
 		/* Parse sensitivity. */
-		levdatum = hashtab_search(&pol->p_levels.table, sensitivity);
+		levdatum = symtab_search(&pol->p_levels, sensitivity);
 		if (!levdatum)
 			return -EINVAL;
 		context->range.level[l].sens = levdatum->level->sens;
@@ -312,7 +312,7 @@ int mls_context_to_sid(struct policydb *pol,
 				*rngptr++ = '\0';
 			}
 
-			catdatum = hashtab_search(&pol->p_cats.table, cur_cat);
+			catdatum = symtab_search(&pol->p_cats, cur_cat);
 			if (!catdatum)
 				return -EINVAL;
 
@@ -325,7 +325,7 @@ int mls_context_to_sid(struct policydb *pol,
 			if (rngptr == NULL)
 				continue;
 
-			rngdatum = hashtab_search(&pol->p_cats.table, rngptr);
+			rngdatum = symtab_search(&pol->p_cats, rngptr);
 			if (!rngdatum)
 				return -EINVAL;
 
@@ -458,9 +458,10 @@ int mls_convert_context(struct policydb *oldp,
 		return 0;
 
 	for (l = 0; l < 2; l++) {
-		levdatum = hashtab_search(&newp->p_levels.table,
-					  sym_name(oldp, SYM_LEVELS,
-						   oldc->range.level[l].sens - 1));
+		char *name = sym_name(oldp, SYM_LEVELS,
+				      oldc->range.level[l].sens - 1);
+
+		levdatum = symtab_search(&newp->p_levels, name);
 
 		if (!levdatum)
 			return -EINVAL;
@@ -470,7 +471,7 @@ int mls_convert_context(struct policydb *oldp,
 					      node, i) {
 			int rc;
 
-			catdatum = hashtab_search(&newp->p_cats.table,
+			catdatum = symtab_search(&newp->p_cats,
 						 sym_name(oldp, SYM_CATS, i));
 			if (!catdatum)
 				return -EINVAL;
@@ -506,7 +507,7 @@ int mls_compute_sid(struct policydb *p,
 		rtr.source_type = scontext->type;
 		rtr.target_type = tcontext->type;
 		rtr.target_class = tclass;
-		r = hashtab_search(&p->range_tr, &rtr);
+		r = policydb_rangetr_search(p, &rtr);
 		if (r)
 			return mls_range_set(newcontext, r);
 

security/selinux/ss/policydb.h

@@ -324,6 +324,15 @@ extern int policydb_role_isvalid(struct policydb *p, unsigned int role);
 extern int policydb_read(struct policydb *p, void *fp);
 extern int policydb_write(struct policydb *p, void *fp);
 
+extern struct filename_trans_datum *policydb_filenametr_search(
+	struct policydb *p, struct filename_trans_key *key);
+
+extern struct mls_range *policydb_rangetr_search(
+	struct policydb *p, struct range_trans *key);
+
+extern struct role_trans_datum *policydb_roletr_search(
+	struct policydb *p, struct role_trans_key *key);
+
 #define POLICYDB_CONFIG_MLS    1
 
 /* the config flags related to unknown classes/perms are bits 2 and 3 */

security/selinux/ss/services.c

@@ -1441,7 +1441,7 @@ static int string_to_context_struct(struct policydb *pol,
 
 	*p++ = 0;
 
-	usrdatum = hashtab_search(&pol->p_users.table, scontextp);
+	usrdatum = symtab_search(&pol->p_users, scontextp);
 	if (!usrdatum)
 		goto out;
 
@@ -1457,7 +1457,7 @@ static int string_to_context_struct(struct policydb *pol,
 
 	*p++ = 0;
 
-	role = hashtab_search(&pol->p_roles.table, scontextp);
+	role = symtab_search(&pol->p_roles, scontextp);
 	if (!role)
 		goto out;
 	ctx->role = role->value;
@@ -1469,7 +1469,7 @@ static int string_to_context_struct(struct policydb *pol,
 	oldc = *p;
 	*p++ = 0;
 
-	typdatum = hashtab_search(&pol->p_types.table, scontextp);
+	typdatum = symtab_search(&pol->p_types, scontextp);
 	if (!typdatum || typdatum->attribute)
 		goto out;
 
@@ -1671,7 +1671,7 @@ static void filename_compute_type(struct policydb *policydb,
 	ft.tclass = tclass;
 	ft.name = objname;
 
-	datum = hashtab_search(&policydb->filename_trans, &ft);
+	datum = policydb_filenametr_search(policydb, &ft);
 	while (datum) {
 		if (ebitmap_get_bit(&datum->stypes, stype - 1)) {
 			newcontext->type = datum->otype;
@@ -1834,7 +1834,7 @@ static int security_compute_sid(struct selinux_state *state,
 			.tclass = tclass,
 		};
 
-		rtd = hashtab_search(&policydb->role_tr, &rtk);
+		rtd = policydb_roletr_search(policydb, &rtk);
 		if (rtd)
 			newcontext.role = rtd->new_role;
 	}
@@ -2024,7 +2024,7 @@ static int convert_context(struct context *oldc, struct context *newc, void *p)
 
 	/* Convert the user. */
 	rc = -EINVAL;
-	usrdatum = hashtab_search(&args->newp->p_users.table,
+	usrdatum = symtab_search(&args->newp->p_users,
 				 sym_name(args->oldp,
 					  SYM_USERS, oldc->user - 1));
 	if (!usrdatum)
@@ -2033,7 +2033,7 @@ static int convert_context(struct context *oldc, struct context *newc, void *p)
 
 	/* Convert the role. */
 	rc = -EINVAL;
-	role = hashtab_search(&args->newp->p_roles.table,
+	role = symtab_search(&args->newp->p_roles,
 			     sym_name(args->oldp, SYM_ROLES, oldc->role - 1));
 	if (!role)
 		goto bad;
@@ -2041,7 +2041,7 @@ static int convert_context(struct context *oldc, struct context *newc, void *p)
 
 	/* Convert the type. */
 	rc = -EINVAL;
-	typdatum = hashtab_search(&args->newp->p_types.table,
+	typdatum = symtab_search(&args->newp->p_types,
 				 sym_name(args->oldp,
 					  SYM_TYPES, oldc->type - 1));
 	if (!typdatum)
@@ -2623,7 +2623,7 @@ int security_get_user_sids(struct selinux_state *state,
 		goto out_unlock;
 
 	rc = -EINVAL;
-	user = hashtab_search(&policydb->p_users.table, username);
+	user = symtab_search(&policydb->p_users, username);
 	if (!user)
 		goto out_unlock;
 
@@ -2979,7 +2979,7 @@ static int security_preserve_bools(struct selinux_state *state,
 	if (rc)
 		goto out;
 	for (i = 0; i < nbools; i++) {
-		booldatum = hashtab_search(&policydb->p_bools.table, bnames[i]);
+		booldatum = symtab_search(&policydb->p_bools, bnames[i]);
 		if (booldatum)
 			booldatum->state = bvalues[i];
 	}
@@ -3230,7 +3230,7 @@ int security_get_permissions(struct selinux_state *state,
 	read_lock(&state->ss->policy_rwlock);
 
 	rc = -EINVAL;
-	match = hashtab_search(&policydb->p_classes.table, class);
+	match = symtab_search(&policydb->p_classes, class);
 	if (!match) {
 		pr_err("SELinux: %s:  unrecognized class %s\n",
 			__func__, class);
@@ -3369,7 +3369,7 @@ int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
 	case AUDIT_SUBJ_USER:
 	case AUDIT_OBJ_USER:
 		rc = -EINVAL;
-		userdatum = hashtab_search(&policydb->p_users.table, rulestr);
+		userdatum = symtab_search(&policydb->p_users, rulestr);
 		if (!userdatum)
 			goto out;
 		tmprule->au_ctxt.user = userdatum->value;
@@ -3377,7 +3377,7 @@ int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
 	case AUDIT_SUBJ_ROLE:
 	case AUDIT_OBJ_ROLE:
 		rc = -EINVAL;
-		roledatum = hashtab_search(&policydb->p_roles.table, rulestr);
+		roledatum = symtab_search(&policydb->p_roles, rulestr);
 		if (!roledatum)
 			goto out;
 		tmprule->au_ctxt.role = roledatum->value;
@@ -3385,7 +3385,7 @@ int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
 	case AUDIT_SUBJ_TYPE:
 	case AUDIT_OBJ_TYPE:
 		rc = -EINVAL;
-		typedatum = hashtab_search(&policydb->p_types.table, rulestr);
+		typedatum = symtab_search(&policydb->p_types, rulestr);
 		if (!typedatum)
 			goto out;
 		tmprule->au_ctxt.type = typedatum->value;

security/selinux/ss/symtab.c

@@ -9,7 +9,7 @@
 #include <linux/errno.h>
 #include "symtab.h"
 
-static unsigned int symhash(struct hashtab *h, const void *key)
+static unsigned int symhash(const void *key)
 {
 	const char *p, *keyp;
 	unsigned int size;
@@ -20,10 +20,10 @@ static unsigned int symhash(struct hashtab *h, const void *key)
 	size = strlen(keyp);
 	for (p = keyp; (p - keyp) < size; p++)
 		val = (val << 4 | (val >> (8*sizeof(unsigned int)-4))) ^ (*p);
-	return val & (h->size - 1);
+	return val;
 }
 
-static int symcmp(struct hashtab *h, const void *key1, const void *key2)
+static int symcmp(const void *key1, const void *key2)
 {
 	const char *keyp1, *keyp2;
 
@@ -32,10 +32,23 @@ static int symcmp(struct hashtab *h, const void *key1, const void *key2)
 	return strcmp(keyp1, keyp2);
 }
 
+static const struct hashtab_key_params symtab_key_params = {
+	.hash = symhash,
+	.cmp = symcmp,
+};
 
 int symtab_init(struct symtab *s, unsigned int size)
 {
 	s->nprim = 0;
-	return hashtab_init(&s->table, symhash, symcmp, size);
+	return hashtab_init(&s->table, size);
 }
 
+int symtab_insert(struct symtab *s, char *name, void *datum)
+{
+	return hashtab_insert(&s->table, name, datum, symtab_key_params);
+}
+
+void *symtab_search(struct symtab *s, const char *name)
+{
+	return hashtab_search(&s->table, name, symtab_key_params);
+}

security/selinux/ss/symtab.h

@@ -19,6 +19,9 @@ struct symtab {
 
 int symtab_init(struct symtab *s, unsigned int size);
 
+int symtab_insert(struct symtab *s, char *name, void *datum);
+void *symtab_search(struct symtab *s, const char *name);
+
 #endif	/* _SS_SYMTAB_H_ */