[PATCH v2 0/5] selinux: Assorted simplifications and cleanups

[PATCH v2 0/5] selinux: Assorted simplifications and cleanups

[Ondrej Mosnacek]

This series contains some boolean code simplifications that I discovered
while working on another patch. I believe they also save some run time
(although not in any perf-critical paths) and some memory overhead.

Changes in v2:
 - drop already merged 1st patch
 - drop the rewrite of security_preserve_bools(), keep only the
   evaluate_cond_node() return type change (requested by Paul)

Ondrej Mosnacek (5):
  selinux: simplify evaluate_cond_node()
  selinux: convert cond_list to array
  selinux: convert cond_av_list to array
  selinux: convert cond_expr to array
  selinux: generalize evaluate_cond_node()

 security/selinux/include/conditional.h |   6 +-
 security/selinux/selinuxfs.c           |   4 +-
 security/selinux/ss/conditional.c      | 252 ++++++++++---------------
 security/selinux/ss/conditional.h      |  27 +--
 security/selinux/ss/policydb.c         |   2 +-
 security/selinux/ss/policydb.h         |   3 +-
 security/selinux/ss/services.c         |  32 ++--
 7 files changed, 137 insertions(+), 189 deletions(-)

-- 
2.24.1

[PATCH v2 1/5] selinux: simplify evaluate_cond_node()

[Ondrej Mosnacek]

It never fails, so it can just return void.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
---
 security/selinux/ss/conditional.c |  3 +--
 security/selinux/ss/conditional.h |  2 +-
 security/selinux/ss/services.c    | 14 ++++----------
 3 files changed, 6 insertions(+), 13 deletions(-)

diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c
index 70c378ee1a2f..04593062008d 100644
--- a/security/selinux/ss/conditional.c
+++ b/security/selinux/ss/conditional.c
@@ -85,7 +85,7 @@ static int cond_evaluate_expr(struct policydb *p, struct cond_expr *expr)
  * list appropriately. If the result of the expression is undefined
  * all of the rules are disabled for safety.
  */
-int evaluate_cond_node(struct policydb *p, struct cond_node *node)
+void evaluate_cond_node(struct policydb *p, struct cond_node *node)
 {
 	int new_state;
 	struct cond_av_list *cur;
@@ -111,7 +111,6 @@ int evaluate_cond_node(struct policydb *p, struct cond_node *node)
 				cur->node->key.specified |= AVTAB_ENABLED;
 		}
 	}
-	return 0;
 }
 
 int cond_policydb_init(struct policydb *p)
diff --git a/security/selinux/ss/conditional.h b/security/selinux/ss/conditional.h
index ec846e45904c..d86ef286ca84 100644
--- a/security/selinux/ss/conditional.h
+++ b/security/selinux/ss/conditional.h
@@ -75,6 +75,6 @@ void cond_compute_av(struct avtab *ctab, struct avtab_key *key,
 		struct av_decision *avd, struct extended_perms *xperms);
 void cond_compute_xperms(struct avtab *ctab, struct avtab_key *key,
 		struct extended_perms_decision *xpermd);
-int evaluate_cond_node(struct policydb *p, struct cond_node *node);
+void evaluate_cond_node(struct policydb *p, struct cond_node *node);
 
 #endif /* _CONDITIONAL_H_ */
diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
index 216ce602a2b5..ff43a35bb874 100644
--- a/security/selinux/ss/services.c
+++ b/security/selinux/ss/services.c
@@ -2958,11 +2958,8 @@ int security_set_bools(struct selinux_state *state, int len, int *values)
 			policydb->bool_val_to_struct[i]->state = 0;
 	}
 
-	for (cur = policydb->cond_list; cur; cur = cur->next) {
-		rc = evaluate_cond_node(policydb, cur);
-		if (rc)
-			goto out;
-	}
+	for (cur = policydb->cond_list; cur; cur = cur->next)
+		evaluate_cond_node(policydb, cur);
 
 	seqno = ++state->ss->latest_granting;
 	rc = 0;
@@ -3015,11 +3012,8 @@ static int security_preserve_bools(struct selinux_state *state,
 		if (booldatum)
 			booldatum->state = bvalues[i];
 	}
-	for (cur = policydb->cond_list; cur; cur = cur->next) {
-		rc = evaluate_cond_node(policydb, cur);
-		if (rc)
-			goto out;
-	}
+	for (cur = policydb->cond_list; cur; cur = cur->next)
+		evaluate_cond_node(policydb, cur);
 
 out:
 	if (bnames) {
-- 
2.24.1

[PATCH v2 2/5] selinux: convert cond_list to array

[Ondrej Mosnacek]

Since it is fixed-size after allocation and we know the size beforehand,
using a plain old array is simpler and more efficient.

While there, also fix signedness of some related variables/parameters.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
---
 security/selinux/include/conditional.h |  6 +--
 security/selinux/selinuxfs.c           |  4 +-
 security/selinux/ss/conditional.c      | 54 ++++++++++----------------
 security/selinux/ss/conditional.h      |  3 +-
 security/selinux/ss/policydb.c         |  2 +-
 security/selinux/ss/policydb.h         |  3 +-
 security/selinux/ss/services.c         | 28 ++++++-------
 7 files changed, 43 insertions(+), 57 deletions(-)

diff --git a/security/selinux/include/conditional.h b/security/selinux/include/conditional.h
index 0ab316f61da0..ffb9a33341f8 100644
--- a/security/selinux/include/conditional.h
+++ b/security/selinux/include/conditional.h
@@ -14,12 +14,12 @@
 #include "security.h"
 
 int security_get_bools(struct selinux_state *state,
-		       int *len, char ***names, int **values);
+		       u32 *len, char ***names, int **values);
 
 int security_set_bools(struct selinux_state *state,
-		       int len, int *values);
+		       u32 len, int *values);
 
 int security_get_bool_value(struct selinux_state *state,
-			    int index);
+			    u32 index);
 
 #endif
diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c
index 79c710911a3c..296ce86e8b1f 100644
--- a/security/selinux/selinuxfs.c
+++ b/security/selinux/selinuxfs.c
@@ -1327,14 +1327,14 @@ static void sel_remove_entries(struct dentry *de)
 
 static int sel_make_bools(struct selinux_fs_info *fsi)
 {
-	int i, ret;
+	int ret;
 	ssize_t len;
 	struct dentry *dentry = NULL;
 	struct dentry *dir = fsi->bool_dir;
 	struct inode *inode = NULL;
 	struct inode_security_struct *isec;
 	char **names = NULL, *page;
-	int num;
+	u32 i, num;
 	int *values = NULL;
 	u32 sid;
 
diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c
index 04593062008d..c8a02c9b23ee 100644
--- a/security/selinux/ss/conditional.c
+++ b/security/selinux/ss/conditional.c
@@ -119,6 +119,7 @@ int cond_policydb_init(struct policydb *p)
 
 	p->bool_val_to_struct = NULL;
 	p->cond_list = NULL;
+	p->cond_list_len = 0;
 
 	rc = avtab_init(&p->te_cond_avtab);
 	if (rc)
@@ -147,27 +148,22 @@ static void cond_node_destroy(struct cond_node *node)
 	}
 	cond_av_list_destroy(node->true_list);
 	cond_av_list_destroy(node->false_list);
-	kfree(node);
 }
 
-static void cond_list_destroy(struct cond_node *list)
+static void cond_list_destroy(struct policydb *p)
 {
-	struct cond_node *next, *cur;
+	u32 i;
 
-	if (list == NULL)
-		return;
-
-	for (cur = list; cur; cur = next) {
-		next = cur->next;
-		cond_node_destroy(cur);
-	}
+	for (i = 0; i < p->cond_list_len; i++)
+		cond_node_destroy(&p->cond_list[i]);
+	kfree(p->cond_list);
 }
 
 void cond_policydb_destroy(struct policydb *p)
 {
 	kfree(p->bool_val_to_struct);
 	avtab_destroy(&p->te_cond_avtab);
-	cond_list_destroy(p->cond_list);
+	cond_list_destroy(p);
 }
 
 int cond_init_bool_indexes(struct policydb *p)
@@ -447,7 +443,6 @@ err:
 
 int cond_read_list(struct policydb *p, void *fp)
 {
-	struct cond_node *node, *last = NULL;
 	__le32 buf[1];
 	u32 i, len;
 	int rc;
@@ -458,29 +453,24 @@ int cond_read_list(struct policydb *p, void *fp)
 
 	len = le32_to_cpu(buf[0]);
 
+	p->cond_list = kcalloc(len, sizeof(*p->cond_list), GFP_KERNEL);
+	if (!p->cond_list)
+		return rc;
+
 	rc = avtab_alloc(&(p->te_cond_avtab), p->te_avtab.nel);
 	if (rc)
 		goto err;
 
 	for (i = 0; i < len; i++) {
-		rc = -ENOMEM;
-		node = kzalloc(sizeof(*node), GFP_KERNEL);
-		if (!node)
-			goto err;
-
-		rc = cond_read_node(p, node, fp);
+		rc = cond_read_node(p, &p->cond_list[i], fp);
 		if (rc)
 			goto err;
-
-		if (i == 0)
-			p->cond_list = node;
-		else
-			last->next = node;
-		last = node;
 	}
+
+	p->cond_list_len = len;
 	return 0;
 err:
-	cond_list_destroy(p->cond_list);
+	cond_list_destroy(p);
 	p->cond_list = NULL;
 	return rc;
 }
@@ -585,23 +575,19 @@ static int cond_write_node(struct policydb *p, struct cond_node *node,
 	return 0;
 }
 
-int cond_write_list(struct policydb *p, struct cond_node *list, void *fp)
+int cond_write_list(struct policydb *p, void *fp)
 {
-	struct cond_node *cur;
-	u32 len;
+	u32 i;
 	__le32 buf[1];
 	int rc;
 
-	len = 0;
-	for (cur = list; cur != NULL; cur = cur->next)
-		len++;
-	buf[0] = cpu_to_le32(len);
+	buf[0] = cpu_to_le32(p->cond_list_len);
 	rc = put_entry(buf, sizeof(u32), 1, fp);
 	if (rc)
 		return rc;
 
-	for (cur = list; cur != NULL; cur = cur->next) {
-		rc = cond_write_node(p, cur, fp);
+	for (i = 0; i < p->cond_list_len; i++) {
+		rc = cond_write_node(p, &p->cond_list[i], fp);
 		if (rc)
 			return rc;
 	}
diff --git a/security/selinux/ss/conditional.h b/security/selinux/ss/conditional.h
index d86ef286ca84..e474bdd3a0ed 100644
--- a/security/selinux/ss/conditional.h
+++ b/security/selinux/ss/conditional.h
@@ -55,7 +55,6 @@ struct cond_node {
 	struct cond_expr *expr;
 	struct cond_av_list *true_list;
 	struct cond_av_list *false_list;
-	struct cond_node *next;
 };
 
 int cond_policydb_init(struct policydb *p);
@@ -69,7 +68,7 @@ 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_list(struct policydb *p, void *fp);
 int cond_write_bool(void *key, void *datum, void *ptr);
-int cond_write_list(struct policydb *p, struct cond_node *list, void *fp);
+int cond_write_list(struct policydb *p, void *fp);
 
 void cond_compute_av(struct avtab *ctab, struct avtab_key *key,
 		struct av_decision *avd, struct extended_perms *xperms);
diff --git a/security/selinux/ss/policydb.c b/security/selinux/ss/policydb.c
index 2aa7f2e1a8e7..8ac9b9ffc83c 100644
--- a/security/selinux/ss/policydb.c
+++ b/security/selinux/ss/policydb.c
@@ -3483,7 +3483,7 @@ int policydb_write(struct policydb *p, void *fp)
 	if (rc)
 		return rc;
 
-	rc = cond_write_list(p, p->cond_list, fp);
+	rc = cond_write_list(p, fp);
 	if (rc)
 		return rc;
 
diff --git a/security/selinux/ss/policydb.h b/security/selinux/ss/policydb.h
index 69b24191fa38..6459616f8487 100644
--- a/security/selinux/ss/policydb.h
+++ b/security/selinux/ss/policydb.h
@@ -272,8 +272,9 @@ struct policydb {
 	struct cond_bool_datum **bool_val_to_struct;
 	/* type enforcement conditional access vectors and transitions */
 	struct avtab te_cond_avtab;
-	/* linked list indexing te_cond_avtab by conditional */
+	/* array indexing te_cond_avtab by conditional */
 	struct cond_node *cond_list;
+	u32 cond_list_len;
 
 	/* role allows */
 	struct role_allow *role_allow;
diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
index ff43a35bb874..8fc8ec317bb6 100644
--- a/security/selinux/ss/services.c
+++ b/security/selinux/ss/services.c
@@ -2868,10 +2868,11 @@ out:
 }
 
 int security_get_bools(struct selinux_state *state,
-		       int *len, char ***names, int **values)
+		       u32 *len, char ***names, int **values)
 {
 	struct policydb *policydb;
-	int i, rc;
+	u32 i;
+	int rc;
 
 	if (!selinux_initialized(state)) {
 		*len = 0;
@@ -2925,12 +2926,11 @@ err:
 }
 
 
-int security_set_bools(struct selinux_state *state, int len, int *values)
+int security_set_bools(struct selinux_state *state, u32 len, int *values)
 {
 	struct policydb *policydb;
-	int i, rc;
-	int lenp, seqno = 0;
-	struct cond_node *cur;
+	int rc;
+	u32 i, lenp, seqno = 0;
 
 	write_lock_irq(&state->ss->policy_rwlock);
 
@@ -2958,8 +2958,8 @@ int security_set_bools(struct selinux_state *state, int len, int *values)
 			policydb->bool_val_to_struct[i]->state = 0;
 	}
 
-	for (cur = policydb->cond_list; cur; cur = cur->next)
-		evaluate_cond_node(policydb, cur);
+	for (i = 0; i < policydb->cond_list_len; i++)
+		evaluate_cond_node(policydb, &policydb->cond_list[i]);
 
 	seqno = ++state->ss->latest_granting;
 	rc = 0;
@@ -2975,11 +2975,11 @@ out:
 }
 
 int security_get_bool_value(struct selinux_state *state,
-			    int index)
+			    u32 index)
 {
 	struct policydb *policydb;
 	int rc;
-	int len;
+	u32 len;
 
 	read_lock(&state->ss->policy_rwlock);
 
@@ -2999,10 +2999,10 @@ out:
 static int security_preserve_bools(struct selinux_state *state,
 				   struct policydb *policydb)
 {
-	int rc, nbools = 0, *bvalues = NULL, i;
+	int rc, *bvalues = NULL;
 	char **bnames = NULL;
 	struct cond_bool_datum *booldatum;
-	struct cond_node *cur;
+	u32 i, nbools = 0;
 
 	rc = security_get_bools(state, &nbools, &bnames, &bvalues);
 	if (rc)
@@ -3012,8 +3012,8 @@ static int security_preserve_bools(struct selinux_state *state,
 		if (booldatum)
 			booldatum->state = bvalues[i];
 	}
-	for (cur = policydb->cond_list; cur; cur = cur->next)
-		evaluate_cond_node(policydb, cur);
+	for (i = 0; i < policydb->cond_list_len; i++)
+		evaluate_cond_node(policydb, &policydb->cond_list[i]);
 
 out:
 	if (bnames) {
-- 
2.24.1

[PATCH v2 3/5] selinux: convert cond_av_list to array

[Ondrej Mosnacek]

Since it is fixed-size after allocation and we know the size beforehand,
using a plain old array is simpler and more efficient.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov>
---
 security/selinux/ss/conditional.c | 125 ++++++++++++------------------
 security/selinux/ss/conditional.h |   8 +-
 2 files changed, 53 insertions(+), 80 deletions(-)

diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c
index c8a02c9b23ee..b847fd2a6a51 100644
--- a/security/selinux/ss/conditional.c
+++ b/security/selinux/ss/conditional.c
@@ -87,8 +87,9 @@ static int cond_evaluate_expr(struct policydb *p, struct cond_expr *expr)
  */
 void evaluate_cond_node(struct policydb *p, struct cond_node *node)
 {
+	struct avtab_node *avnode;
 	int new_state;
-	struct cond_av_list *cur;
+	u32 i;
 
 	new_state = cond_evaluate_expr(p, node->expr);
 	if (new_state != node->cur_state) {
@@ -96,19 +97,21 @@ void evaluate_cond_node(struct policydb *p, struct cond_node *node)
 		if (new_state == -1)
 			pr_err("SELinux: expression result was undefined - disabling all rules.\n");
 		/* turn the rules on or off */
-		for (cur = node->true_list; cur; cur = cur->next) {
+		for (i = 0; i < node->true_list.len; i++) {
+			avnode = node->true_list.nodes[i];
 			if (new_state <= 0)
-				cur->node->key.specified &= ~AVTAB_ENABLED;
+				avnode->key.specified &= ~AVTAB_ENABLED;
 			else
-				cur->node->key.specified |= AVTAB_ENABLED;
+				avnode->key.specified |= AVTAB_ENABLED;
 		}
 
-		for (cur = node->false_list; cur; cur = cur->next) {
+		for (i = 0; i < node->false_list.len; i++) {
+			avnode = node->false_list.nodes[i];
 			/* -1 or 1 */
 			if (new_state)
-				cur->node->key.specified &= ~AVTAB_ENABLED;
+				avnode->key.specified &= ~AVTAB_ENABLED;
 			else
-				cur->node->key.specified |= AVTAB_ENABLED;
+				avnode->key.specified |= AVTAB_ENABLED;
 		}
 	}
 }
@@ -128,16 +131,6 @@ int cond_policydb_init(struct policydb *p)
 	return 0;
 }
 
-static void cond_av_list_destroy(struct cond_av_list *list)
-{
-	struct cond_av_list *cur, *next;
-	for (cur = list; cur; cur = next) {
-		next = cur->next;
-		/* the avtab_ptr_t node is destroy by the avtab */
-		kfree(cur);
-	}
-}
-
 static void cond_node_destroy(struct cond_node *node)
 {
 	struct cond_expr *cur_expr, *next_expr;
@@ -146,8 +139,9 @@ static void cond_node_destroy(struct cond_node *node)
 		next_expr = cur_expr->next;
 		kfree(cur_expr);
 	}
-	cond_av_list_destroy(node->true_list);
-	cond_av_list_destroy(node->false_list);
+	/* the avtab_ptr_t nodes are destroyed by the avtab */
+	kfree(node->true_list.nodes);
+	kfree(node->false_list.nodes);
 }
 
 static void cond_list_destroy(struct policydb *p)
@@ -255,19 +249,17 @@ err:
 
 struct cond_insertf_data {
 	struct policydb *p;
+	struct avtab_node **dst;
 	struct cond_av_list *other;
-	struct cond_av_list *head;
-	struct cond_av_list *tail;
 };
 
 static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum *d, void *ptr)
 {
 	struct cond_insertf_data *data = ptr;
 	struct policydb *p = data->p;
-	struct cond_av_list *other = data->other, *list, *cur;
 	struct avtab_node *node_ptr;
-	u8 found;
-	int rc = -EINVAL;
+	u32 i;
+	bool found;
 
 	/*
 	 * For type rules we have to make certain there aren't any
@@ -277,7 +269,7 @@ static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum
 	if (k->specified & AVTAB_TYPE) {
 		if (avtab_search(&p->te_avtab, k)) {
 			pr_err("SELinux: type rule already exists outside of a conditional.\n");
-			goto err;
+			return -EINVAL;
 		}
 		/*
 		 * If we are reading the false list other will be a pointer to
@@ -287,29 +279,29 @@ static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum
 		 * If we are reading the true list (other == NULL) there shouldn't
 		 * be any other entries.
 		 */
-		if (other) {
+		if (data->other) {
 			node_ptr = avtab_search_node(&p->te_cond_avtab, k);
 			if (node_ptr) {
 				if (avtab_search_node_next(node_ptr, k->specified)) {
 					pr_err("SELinux: too many conflicting type rules.\n");
-					goto err;
+					return -EINVAL;
 				}
-				found = 0;
-				for (cur = other; cur; cur = cur->next) {
-					if (cur->node == node_ptr) {
-						found = 1;
+				found = false;
+				for (i = 0; i < data->other->len; i++) {
+					if (data->other->nodes[i] == node_ptr) {
+						found = true;
 						break;
 					}
 				}
 				if (!found) {
 					pr_err("SELinux: conflicting type rules.\n");
-					goto err;
+					return -EINVAL;
 				}
 			}
 		} else {
 			if (avtab_search(&p->te_cond_avtab, k)) {
 				pr_err("SELinux: conflicting type rules when adding type rule for true.\n");
-				goto err;
+				return -EINVAL;
 			}
 		}
 	}
@@ -317,39 +309,22 @@ static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum
 	node_ptr = avtab_insert_nonunique(&p->te_cond_avtab, k, d);
 	if (!node_ptr) {
 		pr_err("SELinux: could not insert rule.\n");
-		rc = -ENOMEM;
-		goto err;
-	}
-
-	list = kzalloc(sizeof(*list), GFP_KERNEL);
-	if (!list) {
-		rc = -ENOMEM;
-		goto err;
+		return -ENOMEM;
 	}
 
-	list->node = node_ptr;
-	if (!data->head)
-		data->head = list;
-	else
-		data->tail->next = list;
-	data->tail = list;
+	*data->dst = node_ptr;
 	return 0;
-
-err:
-	cond_av_list_destroy(data->head);
-	data->head = NULL;
-	return rc;
 }
 
-static int cond_read_av_list(struct policydb *p, void *fp, struct cond_av_list **ret_list, struct cond_av_list *other)
+static int cond_read_av_list(struct policydb *p, void *fp,
+			     struct cond_av_list *list,
+			     struct cond_av_list *other)
 {
-	int i, rc;
+	int rc;
 	__le32 buf[1];
-	u32 len;
+	u32 i, len;
 	struct cond_insertf_data data;
 
-	*ret_list = NULL;
-
 	rc = next_entry(buf, fp, sizeof(u32));
 	if (rc)
 		return rc;
@@ -358,18 +333,24 @@ static int cond_read_av_list(struct policydb *p, void *fp, struct cond_av_list *
 	if (len == 0)
 		return 0;
 
+	list->nodes = kcalloc(len, sizeof(*list->nodes), GFP_KERNEL);
+	if (!list->nodes)
+		return -ENOMEM;
+
 	data.p = p;
 	data.other = other;
-	data.head = NULL;
-	data.tail = NULL;
 	for (i = 0; i < len; i++) {
+		data.dst = &list->nodes[i];
 		rc = avtab_read_item(&p->te_cond_avtab, fp, p, cond_insertf,
 				     &data);
-		if (rc)
+		if (rc) {
+			kfree(list->nodes);
+			list->nodes = NULL;
 			return rc;
+		}
 	}
 
-	*ret_list = data.head;
+	list->len = len;
 	return 0;
 }
 
@@ -432,7 +413,7 @@ static int cond_read_node(struct policydb *p, struct cond_node *node, void *fp)
 	rc = cond_read_av_list(p, fp, &node->true_list, NULL);
 	if (rc)
 		goto err;
-	rc = cond_read_av_list(p, fp, &node->false_list, node->true_list);
+	rc = cond_read_av_list(p, fp, &node->false_list, &node->true_list);
 	if (rc)
 		goto err;
 	return 0;
@@ -511,24 +492,16 @@ static int cond_write_av_list(struct policydb *p,
 			      struct cond_av_list *list, struct policy_file *fp)
 {
 	__le32 buf[1];
-	struct cond_av_list *cur_list;
-	u32 len;
+	u32 i;
 	int rc;
 
-	len = 0;
-	for (cur_list = list; cur_list != NULL; cur_list = cur_list->next)
-		len++;
-
-	buf[0] = cpu_to_le32(len);
+	buf[0] = cpu_to_le32(list->len);
 	rc = put_entry(buf, sizeof(u32), 1, fp);
 	if (rc)
 		return rc;
 
-	if (len == 0)
-		return 0;
-
-	for (cur_list = list; cur_list != NULL; cur_list = cur_list->next) {
-		rc = avtab_write_item(p, cur_list->node, fp);
+	for (i = 0; i < list->len; i++) {
+		rc = avtab_write_item(p, list->nodes[i], fp);
 		if (rc)
 			return rc;
 	}
@@ -565,10 +538,10 @@ static int cond_write_node(struct policydb *p, struct cond_node *node,
 			return rc;
 	}
 
-	rc = cond_write_av_list(p, node->true_list, fp);
+	rc = cond_write_av_list(p, &node->true_list, fp);
 	if (rc)
 		return rc;
-	rc = cond_write_av_list(p, node->false_list, fp);
+	rc = cond_write_av_list(p, &node->false_list, fp);
 	if (rc)
 		return rc;
 
diff --git a/security/selinux/ss/conditional.h b/security/selinux/ss/conditional.h
index e474bdd3a0ed..5f97f678440e 100644
--- a/security/selinux/ss/conditional.h
+++ b/security/selinux/ss/conditional.h
@@ -39,8 +39,8 @@ struct cond_expr {
  * struct is for that list.
  */
 struct cond_av_list {
-	struct avtab_node *node;
-	struct cond_av_list *next;
+	struct avtab_node **nodes;
+	u32 len;
 };
 
 /*
@@ -53,8 +53,8 @@ struct cond_av_list {
 struct cond_node {
 	int cur_state;
 	struct cond_expr *expr;
-	struct cond_av_list *true_list;
-	struct cond_av_list *false_list;
+	struct cond_av_list true_list;
+	struct cond_av_list false_list;
 };
 
 int cond_policydb_init(struct policydb *p);
-- 
2.24.1

[PATCH v2 4/5] selinux: convert cond_expr to array

[Ondrej Mosnacek]

Since it is fixed-size after allocation and we know the size beforehand,
using a plain old array is simpler and more efficient.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov>
---
 security/selinux/ss/conditional.c | 62 ++++++++++++-------------------
 security/selinux/ss/conditional.h | 14 ++++---
 2 files changed, 33 insertions(+), 43 deletions(-)

diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c
index b847fd2a6a51..8f9f2f3c86a0 100644
--- a/security/selinux/ss/conditional.c
+++ b/security/selinux/ss/conditional.c
@@ -23,18 +23,19 @@
  */
 static int cond_evaluate_expr(struct policydb *p, struct cond_expr *expr)
 {
-
-	struct cond_expr *cur;
+	u32 i;
 	int s[COND_EXPR_MAXDEPTH];
 	int sp = -1;
 
-	for (cur = expr; cur; cur = cur->next) {
-		switch (cur->expr_type) {
+	for (i = 0; i < expr->len; i++) {
+		struct cond_expr_node *node = &expr->nodes[i];
+
+		switch (node->expr_type) {
 		case COND_BOOL:
 			if (sp == (COND_EXPR_MAXDEPTH - 1))
 				return -1;
 			sp++;
-			s[sp] = p->bool_val_to_struct[cur->bool - 1]->state;
+			s[sp] = p->bool_val_to_struct[node->bool - 1]->state;
 			break;
 		case COND_NOT:
 			if (sp < 0)
@@ -91,7 +92,7 @@ void evaluate_cond_node(struct policydb *p, struct cond_node *node)
 	int new_state;
 	u32 i;
 
-	new_state = cond_evaluate_expr(p, node->expr);
+	new_state = cond_evaluate_expr(p, &node->expr);
 	if (new_state != node->cur_state) {
 		node->cur_state = new_state;
 		if (new_state == -1)
@@ -133,12 +134,7 @@ int cond_policydb_init(struct policydb *p)
 
 static void cond_node_destroy(struct cond_node *node)
 {
-	struct cond_expr *cur_expr, *next_expr;
-
-	for (cur_expr = node->expr; cur_expr; cur_expr = next_expr) {
-		next_expr = cur_expr->next;
-		kfree(cur_expr);
-	}
+	kfree(node->expr.nodes);
 	/* the avtab_ptr_t nodes are destroyed by the avtab */
 	kfree(node->true_list.nodes);
 	kfree(node->false_list.nodes);
@@ -354,7 +350,7 @@ static int cond_read_av_list(struct policydb *p, void *fp,
 	return 0;
 }
 
-static int expr_isvalid(struct policydb *p, struct cond_expr *expr)
+static int expr_node_isvalid(struct policydb *p, struct cond_expr_node *expr)
 {
 	if (expr->expr_type <= 0 || expr->expr_type > COND_LAST) {
 		pr_err("SELinux: conditional expressions uses unknown operator.\n");
@@ -371,43 +367,37 @@ static int expr_isvalid(struct policydb *p, struct cond_expr *expr)
 static int cond_read_node(struct policydb *p, struct cond_node *node, void *fp)
 {
 	__le32 buf[2];
-	u32 len, i;
+	u32 i, len;
 	int rc;
-	struct cond_expr *expr = NULL, *last = NULL;
 
 	rc = next_entry(buf, fp, sizeof(u32) * 2);
 	if (rc)
-		goto err;
+		return rc;
 
 	node->cur_state = le32_to_cpu(buf[0]);
 
 	/* expr */
 	len = le32_to_cpu(buf[1]);
+	node->expr.nodes = kcalloc(len, sizeof(*node->expr.nodes), GFP_KERNEL);
+	if (!node->expr.nodes)
+		return -ENOMEM;
+
+	node->expr.len = len;
 
 	for (i = 0; i < len; i++) {
+		struct cond_expr_node *expr = &node->expr.nodes[i];
+
 		rc = next_entry(buf, fp, sizeof(u32) * 2);
 		if (rc)
 			goto err;
 
-		rc = -ENOMEM;
-		expr = kzalloc(sizeof(*expr), GFP_KERNEL);
-		if (!expr)
-			goto err;
-
 		expr->expr_type = le32_to_cpu(buf[0]);
 		expr->bool = le32_to_cpu(buf[1]);
 
-		if (!expr_isvalid(p, expr)) {
+		if (!expr_node_isvalid(p, expr)) {
 			rc = -EINVAL;
-			kfree(expr);
 			goto err;
 		}
-
-		if (i == 0)
-			node->expr = expr;
-		else
-			last->next = expr;
-		last = expr;
 	}
 
 	rc = cond_read_av_list(p, fp, &node->true_list, NULL);
@@ -512,27 +502,23 @@ static int cond_write_av_list(struct policydb *p,
 static int cond_write_node(struct policydb *p, struct cond_node *node,
 		    struct policy_file *fp)
 {
-	struct cond_expr *cur_expr;
 	__le32 buf[2];
 	int rc;
-	u32 len = 0;
+	u32 i;
 
 	buf[0] = cpu_to_le32(node->cur_state);
 	rc = put_entry(buf, sizeof(u32), 1, fp);
 	if (rc)
 		return rc;
 
-	for (cur_expr = node->expr; cur_expr != NULL; cur_expr = cur_expr->next)
-		len++;
-
-	buf[0] = cpu_to_le32(len);
+	buf[0] = cpu_to_le32(node->expr.len);
 	rc = put_entry(buf, sizeof(u32), 1, fp);
 	if (rc)
 		return rc;
 
-	for (cur_expr = node->expr; cur_expr != NULL; cur_expr = cur_expr->next) {
-		buf[0] = cpu_to_le32(cur_expr->expr_type);
-		buf[1] = cpu_to_le32(cur_expr->bool);
+	for (i = 0; i < node->expr.len; i++) {
+		buf[0] = cpu_to_le32(node->expr.nodes[i].expr_type);
+		buf[1] = cpu_to_le32(node->expr.nodes[i].bool);
 		rc = put_entry(buf, sizeof(u32), 2, fp);
 		if (rc)
 			return rc;
diff --git a/security/selinux/ss/conditional.h b/security/selinux/ss/conditional.h
index 5f97f678440e..4677c6ff7450 100644
--- a/security/selinux/ss/conditional.h
+++ b/security/selinux/ss/conditional.h
@@ -19,7 +19,7 @@
  * A conditional expression is a list of operators and operands
  * in reverse polish notation.
  */
-struct cond_expr {
+struct cond_expr_node {
 #define COND_BOOL	1 /* plain bool */
 #define COND_NOT	2 /* !bool */
 #define COND_OR		3 /* bool || bool */
@@ -28,9 +28,13 @@ struct cond_expr {
 #define COND_EQ		6 /* bool == bool */
 #define COND_NEQ	7 /* bool != bool */
 #define COND_LAST	COND_NEQ
-	__u32 expr_type;
-	__u32 bool;
-	struct cond_expr *next;
+	u32 expr_type;
+	u32 bool;
+};
+
+struct cond_expr {
+	struct cond_expr_node *nodes;
+	u32 len;
 };
 
 /*
@@ -52,7 +56,7 @@ struct cond_av_list {
  */
 struct cond_node {
 	int cur_state;
-	struct cond_expr *expr;
+	struct cond_expr expr;
 	struct cond_av_list true_list;
 	struct cond_av_list false_list;
 };
-- 
2.24.1

[PATCH v2 5/5] selinux: generalize evaluate_cond_node()

[Ondrej Mosnacek]

Both callers iterate the cond_list and call it for each node - turn it
into evaluate_cond_nodes(), which does the iteration for them.

Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
---
 security/selinux/ss/conditional.c | 10 +++++++++-
 security/selinux/ss/conditional.h |  2 +-
 security/selinux/ss/services.c    |  6 ++----
 3 files changed, 12 insertions(+), 6 deletions(-)

diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c
index 8f9f2f3c86a0..ad709ccea036 100644
--- a/security/selinux/ss/conditional.c
+++ b/security/selinux/ss/conditional.c
@@ -86,7 +86,7 @@ static int cond_evaluate_expr(struct policydb *p, struct cond_expr *expr)
  * list appropriately. If the result of the expression is undefined
  * all of the rules are disabled for safety.
  */
-void evaluate_cond_node(struct policydb *p, struct cond_node *node)
+static void evaluate_cond_node(struct policydb *p, struct cond_node *node)
 {
 	struct avtab_node *avnode;
 	int new_state;
@@ -117,6 +117,14 @@ void evaluate_cond_node(struct policydb *p, struct cond_node *node)
 	}
 }
 
+void evaluate_cond_nodes(struct policydb *p)
+{
+	u32 i;
+
+	for (i = 0; i < p->cond_list_len; i++)
+		evaluate_cond_node(p, &p->cond_list[i]);
+}
+
 int cond_policydb_init(struct policydb *p)
 {
 	int rc;
diff --git a/security/selinux/ss/conditional.h b/security/selinux/ss/conditional.h
index 4677c6ff7450..b9eb888ffa76 100644
--- a/security/selinux/ss/conditional.h
+++ b/security/selinux/ss/conditional.h
@@ -78,6 +78,6 @@ void cond_compute_av(struct avtab *ctab, struct avtab_key *key,
 		struct av_decision *avd, struct extended_perms *xperms);
 void cond_compute_xperms(struct avtab *ctab, struct avtab_key *key,
 		struct extended_perms_decision *xpermd);
-void evaluate_cond_node(struct policydb *p, struct cond_node *node);
+void evaluate_cond_nodes(struct policydb *p);
 
 #endif /* _CONDITIONAL_H_ */
diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
index 8fc8ec317bb6..7fb7f2efe566 100644
--- a/security/selinux/ss/services.c
+++ b/security/selinux/ss/services.c
@@ -2958,8 +2958,7 @@ int security_set_bools(struct selinux_state *state, u32 len, int *values)
 			policydb->bool_val_to_struct[i]->state = 0;
 	}
 
-	for (i = 0; i < policydb->cond_list_len; i++)
-		evaluate_cond_node(policydb, &policydb->cond_list[i]);
+	evaluate_cond_nodes(policydb);
 
 	seqno = ++state->ss->latest_granting;
 	rc = 0;
@@ -3012,8 +3011,7 @@ static int security_preserve_bools(struct selinux_state *state,
 		if (booldatum)
 			booldatum->state = bvalues[i];
 	}
-	for (i = 0; i < policydb->cond_list_len; i++)
-		evaluate_cond_node(policydb, &policydb->cond_list[i]);
+	evaluate_cond_nodes(policydb);
 
 out:
 	if (bnames) {
-- 
2.24.1

Re: [PATCH v2 1/5] selinux: simplify evaluate_cond_node()

[Stephen Smalley]

On 1/17/20 3:58 AM, Ondrej Mosnacek wrote:
> It never fails, so it can just return void.
> 
> Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>

Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov>

> ---
>   security/selinux/ss/conditional.c |  3 +--
>   security/selinux/ss/conditional.h |  2 +-
>   security/selinux/ss/services.c    | 14 ++++----------
>   3 files changed, 6 insertions(+), 13 deletions(-)
> 
> diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c
> index 70c378ee1a2f..04593062008d 100644
> --- a/security/selinux/ss/conditional.c
> +++ b/security/selinux/ss/conditional.c
> @@ -85,7 +85,7 @@ static int cond_evaluate_expr(struct policydb *p, struct cond_expr *expr)
>    * list appropriately. If the result of the expression is undefined
>    * all of the rules are disabled for safety.
>    */
> -int evaluate_cond_node(struct policydb *p, struct cond_node *node)
> +void evaluate_cond_node(struct policydb *p, struct cond_node *node)
>   {
>   	int new_state;
>   	struct cond_av_list *cur;
> @@ -111,7 +111,6 @@ int evaluate_cond_node(struct policydb *p, struct cond_node *node)
>   				cur->node->key.specified |= AVTAB_ENABLED;
>   		}
>   	}
> -	return 0;
>   }
>   
>   int cond_policydb_init(struct policydb *p)
> diff --git a/security/selinux/ss/conditional.h b/security/selinux/ss/conditional.h
> index ec846e45904c..d86ef286ca84 100644
> --- a/security/selinux/ss/conditional.h
> +++ b/security/selinux/ss/conditional.h
> @@ -75,6 +75,6 @@ void cond_compute_av(struct avtab *ctab, struct avtab_key *key,
>   		struct av_decision *avd, struct extended_perms *xperms);
>   void cond_compute_xperms(struct avtab *ctab, struct avtab_key *key,
>   		struct extended_perms_decision *xpermd);
> -int evaluate_cond_node(struct policydb *p, struct cond_node *node);
> +void evaluate_cond_node(struct policydb *p, struct cond_node *node);
>   
>   #endif /* _CONDITIONAL_H_ */
> diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
> index 216ce602a2b5..ff43a35bb874 100644
> --- a/security/selinux/ss/services.c
> +++ b/security/selinux/ss/services.c
> @@ -2958,11 +2958,8 @@ int security_set_bools(struct selinux_state *state, int len, int *values)
>   			policydb->bool_val_to_struct[i]->state = 0;
>   	}
>   
> -	for (cur = policydb->cond_list; cur; cur = cur->next) {
> -		rc = evaluate_cond_node(policydb, cur);
> -		if (rc)
> -			goto out;
> -	}
> +	for (cur = policydb->cond_list; cur; cur = cur->next)
> +		evaluate_cond_node(policydb, cur);
>   
>   	seqno = ++state->ss->latest_granting;
>   	rc = 0;
> @@ -3015,11 +3012,8 @@ static int security_preserve_bools(struct selinux_state *state,
>   		if (booldatum)
>   			booldatum->state = bvalues[i];
>   	}
> -	for (cur = policydb->cond_list; cur; cur = cur->next) {
> -		rc = evaluate_cond_node(policydb, cur);
> -		if (rc)
> -			goto out;
> -	}
> +	for (cur = policydb->cond_list; cur; cur = cur->next)
> +		evaluate_cond_node(policydb, cur);
>   
>   out:
>   	if (bnames) {
> 

Re: [PATCH v2 2/5] selinux: convert cond_list to array

[Stephen Smalley]

On 1/17/20 3:58 AM, Ondrej Mosnacek wrote:
> Since it is fixed-size after allocation and we know the size beforehand,
> using a plain old array is simpler and more efficient.
> 
> While there, also fix signedness of some related variables/parameters.
> 
> Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>

Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov>

> ---
>   security/selinux/include/conditional.h |  6 +--
>   security/selinux/selinuxfs.c           |  4 +-
>   security/selinux/ss/conditional.c      | 54 ++++++++++----------------
>   security/selinux/ss/conditional.h      |  3 +-
>   security/selinux/ss/policydb.c         |  2 +-
>   security/selinux/ss/policydb.h         |  3 +-
>   security/selinux/ss/services.c         | 28 ++++++-------
>   7 files changed, 43 insertions(+), 57 deletions(-)
> 
> diff --git a/security/selinux/include/conditional.h b/security/selinux/include/conditional.h
> index 0ab316f61da0..ffb9a33341f8 100644
> --- a/security/selinux/include/conditional.h
> +++ b/security/selinux/include/conditional.h
> @@ -14,12 +14,12 @@
>   #include "security.h"
>   
>   int security_get_bools(struct selinux_state *state,
> -		       int *len, char ***names, int **values);
> +		       u32 *len, char ***names, int **values);
>   
>   int security_set_bools(struct selinux_state *state,
> -		       int len, int *values);
> +		       u32 len, int *values);
>   
>   int security_get_bool_value(struct selinux_state *state,
> -			    int index);
> +			    u32 index);
>   
>   #endif
> diff --git a/security/selinux/selinuxfs.c b/security/selinux/selinuxfs.c
> index 79c710911a3c..296ce86e8b1f 100644
> --- a/security/selinux/selinuxfs.c
> +++ b/security/selinux/selinuxfs.c
> @@ -1327,14 +1327,14 @@ static void sel_remove_entries(struct dentry *de)
>   
>   static int sel_make_bools(struct selinux_fs_info *fsi)
>   {
> -	int i, ret;
> +	int ret;
>   	ssize_t len;
>   	struct dentry *dentry = NULL;
>   	struct dentry *dir = fsi->bool_dir;
>   	struct inode *inode = NULL;
>   	struct inode_security_struct *isec;
>   	char **names = NULL, *page;
> -	int num;
> +	u32 i, num;
>   	int *values = NULL;
>   	u32 sid;
>   
> diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c
> index 04593062008d..c8a02c9b23ee 100644
> --- a/security/selinux/ss/conditional.c
> +++ b/security/selinux/ss/conditional.c
> @@ -119,6 +119,7 @@ int cond_policydb_init(struct policydb *p)
>   
>   	p->bool_val_to_struct = NULL;
>   	p->cond_list = NULL;
> +	p->cond_list_len = 0;
>   
>   	rc = avtab_init(&p->te_cond_avtab);
>   	if (rc)
> @@ -147,27 +148,22 @@ static void cond_node_destroy(struct cond_node *node)
>   	}
>   	cond_av_list_destroy(node->true_list);
>   	cond_av_list_destroy(node->false_list);
> -	kfree(node);
>   }
>   
> -static void cond_list_destroy(struct cond_node *list)
> +static void cond_list_destroy(struct policydb *p)
>   {
> -	struct cond_node *next, *cur;
> +	u32 i;
>   
> -	if (list == NULL)
> -		return;
> -
> -	for (cur = list; cur; cur = next) {
> -		next = cur->next;
> -		cond_node_destroy(cur);
> -	}
> +	for (i = 0; i < p->cond_list_len; i++)
> +		cond_node_destroy(&p->cond_list[i]);
> +	kfree(p->cond_list);
>   }
>   
>   void cond_policydb_destroy(struct policydb *p)
>   {
>   	kfree(p->bool_val_to_struct);
>   	avtab_destroy(&p->te_cond_avtab);
> -	cond_list_destroy(p->cond_list);
> +	cond_list_destroy(p);
>   }
>   
>   int cond_init_bool_indexes(struct policydb *p)
> @@ -447,7 +443,6 @@ err:
>   
>   int cond_read_list(struct policydb *p, void *fp)
>   {
> -	struct cond_node *node, *last = NULL;
>   	__le32 buf[1];
>   	u32 i, len;
>   	int rc;
> @@ -458,29 +453,24 @@ int cond_read_list(struct policydb *p, void *fp)
>   
>   	len = le32_to_cpu(buf[0]);
>   
> +	p->cond_list = kcalloc(len, sizeof(*p->cond_list), GFP_KERNEL);
> +	if (!p->cond_list)
> +		return rc;
> +
>   	rc = avtab_alloc(&(p->te_cond_avtab), p->te_avtab.nel);
>   	if (rc)
>   		goto err;
>   
>   	for (i = 0; i < len; i++) {
> -		rc = -ENOMEM;
> -		node = kzalloc(sizeof(*node), GFP_KERNEL);
> -		if (!node)
> -			goto err;
> -
> -		rc = cond_read_node(p, node, fp);
> +		rc = cond_read_node(p, &p->cond_list[i], fp);
>   		if (rc)
>   			goto err;
> -
> -		if (i == 0)
> -			p->cond_list = node;
> -		else
> -			last->next = node;
> -		last = node;
>   	}
> +
> +	p->cond_list_len = len;
>   	return 0;
>   err:
> -	cond_list_destroy(p->cond_list);
> +	cond_list_destroy(p);
>   	p->cond_list = NULL;
>   	return rc;
>   }
> @@ -585,23 +575,19 @@ static int cond_write_node(struct policydb *p, struct cond_node *node,
>   	return 0;
>   }
>   
> -int cond_write_list(struct policydb *p, struct cond_node *list, void *fp)
> +int cond_write_list(struct policydb *p, void *fp)
>   {
> -	struct cond_node *cur;
> -	u32 len;
> +	u32 i;
>   	__le32 buf[1];
>   	int rc;
>   
> -	len = 0;
> -	for (cur = list; cur != NULL; cur = cur->next)
> -		len++;
> -	buf[0] = cpu_to_le32(len);
> +	buf[0] = cpu_to_le32(p->cond_list_len);
>   	rc = put_entry(buf, sizeof(u32), 1, fp);
>   	if (rc)
>   		return rc;
>   
> -	for (cur = list; cur != NULL; cur = cur->next) {
> -		rc = cond_write_node(p, cur, fp);
> +	for (i = 0; i < p->cond_list_len; i++) {
> +		rc = cond_write_node(p, &p->cond_list[i], fp);
>   		if (rc)
>   			return rc;
>   	}
> diff --git a/security/selinux/ss/conditional.h b/security/selinux/ss/conditional.h
> index d86ef286ca84..e474bdd3a0ed 100644
> --- a/security/selinux/ss/conditional.h
> +++ b/security/selinux/ss/conditional.h
> @@ -55,7 +55,6 @@ struct cond_node {
>   	struct cond_expr *expr;
>   	struct cond_av_list *true_list;
>   	struct cond_av_list *false_list;
> -	struct cond_node *next;
>   };
>   
>   int cond_policydb_init(struct policydb *p);
> @@ -69,7 +68,7 @@ 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_list(struct policydb *p, void *fp);
>   int cond_write_bool(void *key, void *datum, void *ptr);
> -int cond_write_list(struct policydb *p, struct cond_node *list, void *fp);
> +int cond_write_list(struct policydb *p, void *fp);
>   
>   void cond_compute_av(struct avtab *ctab, struct avtab_key *key,
>   		struct av_decision *avd, struct extended_perms *xperms);
> diff --git a/security/selinux/ss/policydb.c b/security/selinux/ss/policydb.c
> index 2aa7f2e1a8e7..8ac9b9ffc83c 100644
> --- a/security/selinux/ss/policydb.c
> +++ b/security/selinux/ss/policydb.c
> @@ -3483,7 +3483,7 @@ int policydb_write(struct policydb *p, void *fp)
>   	if (rc)
>   		return rc;
>   
> -	rc = cond_write_list(p, p->cond_list, fp);
> +	rc = cond_write_list(p, fp);
>   	if (rc)
>   		return rc;
>   
> diff --git a/security/selinux/ss/policydb.h b/security/selinux/ss/policydb.h
> index 69b24191fa38..6459616f8487 100644
> --- a/security/selinux/ss/policydb.h
> +++ b/security/selinux/ss/policydb.h
> @@ -272,8 +272,9 @@ struct policydb {
>   	struct cond_bool_datum **bool_val_to_struct;
>   	/* type enforcement conditional access vectors and transitions */
>   	struct avtab te_cond_avtab;
> -	/* linked list indexing te_cond_avtab by conditional */
> +	/* array indexing te_cond_avtab by conditional */
>   	struct cond_node *cond_list;
> +	u32 cond_list_len;
>   
>   	/* role allows */
>   	struct role_allow *role_allow;
> diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
> index ff43a35bb874..8fc8ec317bb6 100644
> --- a/security/selinux/ss/services.c
> +++ b/security/selinux/ss/services.c
> @@ -2868,10 +2868,11 @@ out:
>   }
>   
>   int security_get_bools(struct selinux_state *state,
> -		       int *len, char ***names, int **values)
> +		       u32 *len, char ***names, int **values)
>   {
>   	struct policydb *policydb;
> -	int i, rc;
> +	u32 i;
> +	int rc;
>   
>   	if (!selinux_initialized(state)) {
>   		*len = 0;
> @@ -2925,12 +2926,11 @@ err:
>   }
>   
>   
> -int security_set_bools(struct selinux_state *state, int len, int *values)
> +int security_set_bools(struct selinux_state *state, u32 len, int *values)
>   {
>   	struct policydb *policydb;
> -	int i, rc;
> -	int lenp, seqno = 0;
> -	struct cond_node *cur;
> +	int rc;
> +	u32 i, lenp, seqno = 0;
>   
>   	write_lock_irq(&state->ss->policy_rwlock);
>   
> @@ -2958,8 +2958,8 @@ int security_set_bools(struct selinux_state *state, int len, int *values)
>   			policydb->bool_val_to_struct[i]->state = 0;
>   	}
>   
> -	for (cur = policydb->cond_list; cur; cur = cur->next)
> -		evaluate_cond_node(policydb, cur);
> +	for (i = 0; i < policydb->cond_list_len; i++)
> +		evaluate_cond_node(policydb, &policydb->cond_list[i]);
>   
>   	seqno = ++state->ss->latest_granting;
>   	rc = 0;
> @@ -2975,11 +2975,11 @@ out:
>   }
>   
>   int security_get_bool_value(struct selinux_state *state,
> -			    int index)
> +			    u32 index)
>   {
>   	struct policydb *policydb;
>   	int rc;
> -	int len;
> +	u32 len;
>   
>   	read_lock(&state->ss->policy_rwlock);
>   
> @@ -2999,10 +2999,10 @@ out:
>   static int security_preserve_bools(struct selinux_state *state,
>   				   struct policydb *policydb)
>   {
> -	int rc, nbools = 0, *bvalues = NULL, i;
> +	int rc, *bvalues = NULL;
>   	char **bnames = NULL;
>   	struct cond_bool_datum *booldatum;
> -	struct cond_node *cur;
> +	u32 i, nbools = 0;
>   
>   	rc = security_get_bools(state, &nbools, &bnames, &bvalues);
>   	if (rc)
> @@ -3012,8 +3012,8 @@ static int security_preserve_bools(struct selinux_state *state,
>   		if (booldatum)
>   			booldatum->state = bvalues[i];
>   	}
> -	for (cur = policydb->cond_list; cur; cur = cur->next)
> -		evaluate_cond_node(policydb, cur);
> +	for (i = 0; i < policydb->cond_list_len; i++)
> +		evaluate_cond_node(policydb, &policydb->cond_list[i]);
>   
>   out:
>   	if (bnames) {
> 

Re: [PATCH v2 5/5] selinux: generalize evaluate_cond_node()

[Stephen Smalley]

On 1/17/20 3:58 AM, Ondrej Mosnacek wrote:
> Both callers iterate the cond_list and call it for each node - turn it
> into evaluate_cond_nodes(), which does the iteration for them.
> 
> Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>

Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov>

> ---
>   security/selinux/ss/conditional.c | 10 +++++++++-
>   security/selinux/ss/conditional.h |  2 +-
>   security/selinux/ss/services.c    |  6 ++----
>   3 files changed, 12 insertions(+), 6 deletions(-)
> 
> diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c
> index 8f9f2f3c86a0..ad709ccea036 100644
> --- a/security/selinux/ss/conditional.c
> +++ b/security/selinux/ss/conditional.c
> @@ -86,7 +86,7 @@ static int cond_evaluate_expr(struct policydb *p, struct cond_expr *expr)
>    * list appropriately. If the result of the expression is undefined
>    * all of the rules are disabled for safety.
>    */
> -void evaluate_cond_node(struct policydb *p, struct cond_node *node)
> +static void evaluate_cond_node(struct policydb *p, struct cond_node *node)
>   {
>   	struct avtab_node *avnode;
>   	int new_state;
> @@ -117,6 +117,14 @@ void evaluate_cond_node(struct policydb *p, struct cond_node *node)
>   	}
>   }
>   
> +void evaluate_cond_nodes(struct policydb *p)
> +{
> +	u32 i;
> +
> +	for (i = 0; i < p->cond_list_len; i++)
> +		evaluate_cond_node(p, &p->cond_list[i]);
> +}
> +
>   int cond_policydb_init(struct policydb *p)
>   {
>   	int rc;
> diff --git a/security/selinux/ss/conditional.h b/security/selinux/ss/conditional.h
> index 4677c6ff7450..b9eb888ffa76 100644
> --- a/security/selinux/ss/conditional.h
> +++ b/security/selinux/ss/conditional.h
> @@ -78,6 +78,6 @@ void cond_compute_av(struct avtab *ctab, struct avtab_key *key,
>   		struct av_decision *avd, struct extended_perms *xperms);
>   void cond_compute_xperms(struct avtab *ctab, struct avtab_key *key,
>   		struct extended_perms_decision *xpermd);
> -void evaluate_cond_node(struct policydb *p, struct cond_node *node);
> +void evaluate_cond_nodes(struct policydb *p);
>   
>   #endif /* _CONDITIONAL_H_ */
> diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
> index 8fc8ec317bb6..7fb7f2efe566 100644
> --- a/security/selinux/ss/services.c
> +++ b/security/selinux/ss/services.c
> @@ -2958,8 +2958,7 @@ int security_set_bools(struct selinux_state *state, u32 len, int *values)
>   			policydb->bool_val_to_struct[i]->state = 0;
>   	}
>   
> -	for (i = 0; i < policydb->cond_list_len; i++)
> -		evaluate_cond_node(policydb, &policydb->cond_list[i]);
> +	evaluate_cond_nodes(policydb);
>   
>   	seqno = ++state->ss->latest_granting;
>   	rc = 0;
> @@ -3012,8 +3011,7 @@ static int security_preserve_bools(struct selinux_state *state,
>   		if (booldatum)
>   			booldatum->state = bvalues[i];
>   	}
> -	for (i = 0; i < policydb->cond_list_len; i++)
> -		evaluate_cond_node(policydb, &policydb->cond_list[i]);
> +	evaluate_cond_nodes(policydb);
>   
>   out:
>   	if (bnames) {
> 

Re: [PATCH v2 1/5] selinux: simplify evaluate_cond_node()

[Paul Moore]

On Fri, Jan 17, 2020 at 3:58 AM Ondrej Mosnacek <omosnace@redhat.com> wrote:
>
> It never fails, so it can just return void.
>
> Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
> ---
>  security/selinux/ss/conditional.c |  3 +--
>  security/selinux/ss/conditional.h |  2 +-
>  security/selinux/ss/services.c    | 14 ++++----------
>  3 files changed, 6 insertions(+), 13 deletions(-)

Thanks, I've queued this into selinux/next, you'll see if after the
merge window closes.

-- 
paul moore
www.paul-moore.com

Re: [PATCH v2 2/5] selinux: convert cond_list to array

[Paul Moore]

On Fri, Jan 17, 2020 at 3:58 AM Ondrej Mosnacek <omosnace@redhat.com> wrote:
>
> Since it is fixed-size after allocation and we know the size beforehand,
> using a plain old array is simpler and more efficient.
>
> While there, also fix signedness of some related variables/parameters.
>
> Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
> ---
>  security/selinux/include/conditional.h |  6 +--
>  security/selinux/selinuxfs.c           |  4 +-
>  security/selinux/ss/conditional.c      | 54 ++++++++++----------------
>  security/selinux/ss/conditional.h      |  3 +-
>  security/selinux/ss/policydb.c         |  2 +-
>  security/selinux/ss/policydb.h         |  3 +-
>  security/selinux/ss/services.c         | 28 ++++++-------
>  7 files changed, 43 insertions(+), 57 deletions(-)
>
> diff --git a/security/selinux/include/conditional.h b/security/selinux/include/conditional.h
> index 0ab316f61da0..ffb9a33341f8 100644
> --- a/security/selinux/include/conditional.h
> +++ b/security/selinux/include/conditional.h
> @@ -14,12 +14,12 @@
>  #include "security.h"
>
>  int security_get_bools(struct selinux_state *state,
> -                      int *len, char ***names, int **values);
> +                      u32 *len, char ***names, int **values);
>
>  int security_set_bools(struct selinux_state *state,
> -                      int len, int *values);
> +                      u32 len, int *values);

In the future, if you're making changes like this, you might as well
put it all on one line (it fits under 80 chars).

>  int security_get_bool_value(struct selinux_state *state,
> -                           int index);
> +                           u32 index);

Same here.

> diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c
> index 04593062008d..c8a02c9b23ee 100644
> --- a/security/selinux/ss/conditional.c
> +++ b/security/selinux/ss/conditional.c
> @@ -119,6 +119,7 @@ int cond_policydb_init(struct policydb *p)
>
>         p->bool_val_to_struct = NULL;
>         p->cond_list = NULL;
> +       p->cond_list_len = 0;
>
>         rc = avtab_init(&p->te_cond_avtab);
>         if (rc)
> @@ -147,27 +148,22 @@ static void cond_node_destroy(struct cond_node *node)
>         }
>         cond_av_list_destroy(node->true_list);
>         cond_av_list_destroy(node->false_list);
> -       kfree(node);
>  }
>
> -static void cond_list_destroy(struct cond_node *list)
> +static void cond_list_destroy(struct policydb *p)
>  {
> -       struct cond_node *next, *cur;
> +       u32 i;
>
> -       if (list == NULL)
> -               return;
> -
> -       for (cur = list; cur; cur = next) {
> -               next = cur->next;
> -               cond_node_destroy(cur);
> -       }
> +       for (i = 0; i < p->cond_list_len; i++)
> +               cond_node_destroy(&p->cond_list[i]);
> +       kfree(p->cond_list);
>  }
>
>  void cond_policydb_destroy(struct policydb *p)
>  {
>         kfree(p->bool_val_to_struct);
>         avtab_destroy(&p->te_cond_avtab);
> -       cond_list_destroy(p->cond_list);
> +       cond_list_destroy(p);
>  }
>
>  int cond_init_bool_indexes(struct policydb *p)
> @@ -447,7 +443,6 @@ err:
>
>  int cond_read_list(struct policydb *p, void *fp)
>  {
> -       struct cond_node *node, *last = NULL;
>         __le32 buf[1];
>         u32 i, len;
>         int rc;
> @@ -458,29 +453,24 @@ int cond_read_list(struct policydb *p, void *fp)
>
>         len = le32_to_cpu(buf[0]);
>
> +       p->cond_list = kcalloc(len, sizeof(*p->cond_list), GFP_KERNEL);
> +       if (!p->cond_list)
> +               return rc;
> +
>         rc = avtab_alloc(&(p->te_cond_avtab), p->te_avtab.nel);
>         if (rc)
>                 goto err;
>
>         for (i = 0; i < len; i++) {
> -               rc = -ENOMEM;
> -               node = kzalloc(sizeof(*node), GFP_KERNEL);
> -               if (!node)
> -                       goto err;
> -
> -               rc = cond_read_node(p, node, fp);
> +               rc = cond_read_node(p, &p->cond_list[i], fp);
>                 if (rc)
>                         goto err;
> -
> -               if (i == 0)
> -                       p->cond_list = node;
> -               else
> -                       last->next = node;
> -               last = node;
>         }
> +
> +       p->cond_list_len = len;

Hmmm.  Since we don't update p->cond_list_len until here, if we fail
in the for-loop above and end up jumping to "err" we might not cleanup
all the nodes, right?

>         return 0;
>  err:
> -       cond_list_destroy(p->cond_list);
> +       cond_list_destroy(p);
>         p->cond_list = NULL;
>         return rc;
>  }

-- 
paul moore
www.paul-moore.com

Re: [PATCH v2 3/5] selinux: convert cond_av_list to array

[Paul Moore]

On Fri, Jan 17, 2020 at 3:58 AM Ondrej Mosnacek <omosnace@redhat.com> wrote:
> Since it is fixed-size after allocation and we know the size beforehand,
> using a plain old array is simpler and more efficient.
>
> Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
> Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov>
> ---
>  security/selinux/ss/conditional.c | 125 ++++++++++++------------------
>  security/selinux/ss/conditional.h |   8 +-
>  2 files changed, 53 insertions(+), 80 deletions(-)

...

> diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c
> index c8a02c9b23ee..b847fd2a6a51 100644
> --- a/security/selinux/ss/conditional.c
> +++ b/security/selinux/ss/conditional.c
> @@ -255,19 +249,17 @@ err:
>
>  struct cond_insertf_data {
>         struct policydb *p;
> +       struct avtab_node **dst;
>         struct cond_av_list *other;
> -       struct cond_av_list *head;
> -       struct cond_av_list *tail;
>  };
>
>  static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum *d, void *ptr)
>  {
>         struct cond_insertf_data *data = ptr;
>         struct policydb *p = data->p;
> -       struct cond_av_list *other = data->other, *list, *cur;
>         struct avtab_node *node_ptr;
> -       u8 found;
> -       int rc = -EINVAL;
> +       u32 i;
> +       bool found;
>
>         /*
>          * For type rules we have to make certain there aren't any
> @@ -277,7 +269,7 @@ static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum
>         if (k->specified & AVTAB_TYPE) {
>                 if (avtab_search(&p->te_avtab, k)) {
>                         pr_err("SELinux: type rule already exists outside of a conditional.\n");
> -                       goto err;
> +                       return -EINVAL;
>                 }
>                 /*
>                  * If we are reading the false list other will be a pointer to
> @@ -287,29 +279,29 @@ static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum
>                  * If we are reading the true list (other == NULL) there shouldn't
>                  * be any other entries.
>                  */
> -               if (other) {
> +               if (data->other) {
>                         node_ptr = avtab_search_node(&p->te_cond_avtab, k);
>                         if (node_ptr) {
>                                 if (avtab_search_node_next(node_ptr, k->specified)) {
>                                         pr_err("SELinux: too many conflicting type rules.\n");
> -                                       goto err;
> +                                       return -EINVAL;
>                                 }
> -                               found = 0;
> -                               for (cur = other; cur; cur = cur->next) {
> -                                       if (cur->node == node_ptr) {
> -                                               found = 1;
> +                               found = false;
> +                               for (i = 0; i < data->other->len; i++) {
> +                                       if (data->other->nodes[i] == node_ptr) {
> +                                               found = true;
>                                                 break;
>                                         }
>                                 }

Can you explain why you got rid of the "other" variable in this
function?  It seems like it would be nice in the loop above.

-- 
paul moore
www.paul-moore.com

Re: [PATCH v2 4/5] selinux: convert cond_expr to array

[Paul Moore]

On Fri, Jan 17, 2020 at 3:58 AM Ondrej Mosnacek <omosnace@redhat.com> wrote:
>
> Since it is fixed-size after allocation and we know the size beforehand,
> using a plain old array is simpler and more efficient.
>
> Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
> Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov>
> ---
>  security/selinux/ss/conditional.c | 62 ++++++++++++-------------------
>  security/selinux/ss/conditional.h | 14 ++++---
>  2 files changed, 33 insertions(+), 43 deletions(-)

This patch looks fine, but since I think you may need to respin at
least one of the earlier patches I'm going to hold off on merging this
for now.

-- 
paul moore
www.paul-moore.com

Re: [PATCH v2 5/5] selinux: generalize evaluate_cond_node()

[Paul Moore]

On Fri, Jan 17, 2020 at 3:58 AM Ondrej Mosnacek <omosnace@redhat.com> wrote:
>
> Both callers iterate the cond_list and call it for each node - turn it
> into evaluate_cond_nodes(), which does the iteration for them.
>
> Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
> ---
>  security/selinux/ss/conditional.c | 10 +++++++++-
>  security/selinux/ss/conditional.h |  2 +-
>  security/selinux/ss/services.c    |  6 ++----
>  3 files changed, 12 insertions(+), 6 deletions(-)

Also looks good, but I'm holding off pending a potential respin.

-- 
paul moore
www.paul-moore.com

Re: [PATCH v2 2/5] selinux: convert cond_list to array

[Ondrej Mosnacek]

On Fri, Jan 31, 2020 at 5:05 AM Paul Moore <paul@paul-moore.com> wrote:
> On Fri, Jan 17, 2020 at 3:58 AM Ondrej Mosnacek <omosnace@redhat.com> wrote:
> >
> > Since it is fixed-size after allocation and we know the size beforehand,
> > using a plain old array is simpler and more efficient.
> >
> > While there, also fix signedness of some related variables/parameters.
> >
> > Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
> > ---
> >  security/selinux/include/conditional.h |  6 +--
> >  security/selinux/selinuxfs.c           |  4 +-
> >  security/selinux/ss/conditional.c      | 54 ++++++++++----------------
> >  security/selinux/ss/conditional.h      |  3 +-
> >  security/selinux/ss/policydb.c         |  2 +-
> >  security/selinux/ss/policydb.h         |  3 +-
> >  security/selinux/ss/services.c         | 28 ++++++-------
> >  7 files changed, 43 insertions(+), 57 deletions(-)
> >
> > diff --git a/security/selinux/include/conditional.h b/security/selinux/include/conditional.h
> > index 0ab316f61da0..ffb9a33341f8 100644
> > --- a/security/selinux/include/conditional.h
> > +++ b/security/selinux/include/conditional.h
> > @@ -14,12 +14,12 @@
> >  #include "security.h"
> >
> >  int security_get_bools(struct selinux_state *state,
> > -                      int *len, char ***names, int **values);
> > +                      u32 *len, char ***names, int **values);
> >
> >  int security_set_bools(struct selinux_state *state,
> > -                      int len, int *values);
> > +                      u32 len, int *values);
>
> In the future, if you're making changes like this, you might as well
> put it all on one line (it fits under 80 chars).

Good point, will do that in v3.

>
> >  int security_get_bool_value(struct selinux_state *state,
> > -                           int index);
> > +                           u32 index);
>
> Same here.
>
> > diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c
> > index 04593062008d..c8a02c9b23ee 100644
> > --- a/security/selinux/ss/conditional.c
> > +++ b/security/selinux/ss/conditional.c
> > @@ -119,6 +119,7 @@ int cond_policydb_init(struct policydb *p)
> >
> >         p->bool_val_to_struct = NULL;
> >         p->cond_list = NULL;
> > +       p->cond_list_len = 0;
> >
> >         rc = avtab_init(&p->te_cond_avtab);
> >         if (rc)
> > @@ -147,27 +148,22 @@ static void cond_node_destroy(struct cond_node *node)
> >         }
> >         cond_av_list_destroy(node->true_list);
> >         cond_av_list_destroy(node->false_list);
> > -       kfree(node);
> >  }
> >
> > -static void cond_list_destroy(struct cond_node *list)
> > +static void cond_list_destroy(struct policydb *p)
> >  {
> > -       struct cond_node *next, *cur;
> > +       u32 i;
> >
> > -       if (list == NULL)
> > -               return;
> > -
> > -       for (cur = list; cur; cur = next) {
> > -               next = cur->next;
> > -               cond_node_destroy(cur);
> > -       }
> > +       for (i = 0; i < p->cond_list_len; i++)
> > +               cond_node_destroy(&p->cond_list[i]);
> > +       kfree(p->cond_list);
> >  }
> >
> >  void cond_policydb_destroy(struct policydb *p)
> >  {
> >         kfree(p->bool_val_to_struct);
> >         avtab_destroy(&p->te_cond_avtab);
> > -       cond_list_destroy(p->cond_list);
> > +       cond_list_destroy(p);
> >  }
> >
> >  int cond_init_bool_indexes(struct policydb *p)
> > @@ -447,7 +443,6 @@ err:
> >
> >  int cond_read_list(struct policydb *p, void *fp)
> >  {
> > -       struct cond_node *node, *last = NULL;
> >         __le32 buf[1];
> >         u32 i, len;
> >         int rc;
> > @@ -458,29 +453,24 @@ int cond_read_list(struct policydb *p, void *fp)
> >
> >         len = le32_to_cpu(buf[0]);
> >
> > +       p->cond_list = kcalloc(len, sizeof(*p->cond_list), GFP_KERNEL);
> > +       if (!p->cond_list)
> > +               return rc;
> > +
> >         rc = avtab_alloc(&(p->te_cond_avtab), p->te_avtab.nel);
> >         if (rc)
> >                 goto err;
> >
> >         for (i = 0; i < len; i++) {
> > -               rc = -ENOMEM;
> > -               node = kzalloc(sizeof(*node), GFP_KERNEL);
> > -               if (!node)
> > -                       goto err;
> > -
> > -               rc = cond_read_node(p, node, fp);
> > +               rc = cond_read_node(p, &p->cond_list[i], fp);
> >                 if (rc)
> >                         goto err;
> > -
> > -               if (i == 0)
> > -                       p->cond_list = node;
> > -               else
> > -                       last->next = node;
> > -               last = node;
> >         }
> > +
> > +       p->cond_list_len = len;
>
> Hmmm.  Since we don't update p->cond_list_len until here, if we fail
> in the for-loop above and end up jumping to "err" we might not cleanup
> all the nodes, right?

You're right. I'll fix it by moving the p->cond_list_len assignment
before the for-loop - since the array is zero-initialized by
kcalloc(), cond_node_destroy() can be called safely also on unread
items. (That is a bit inefficient, but I see little value in
micro-optimizing the error path.)

>
> >         return 0;
> >  err:
> > -       cond_list_destroy(p->cond_list);
> > +       cond_list_destroy(p);
> >         p->cond_list = NULL;
> >         return rc;
> >  }
>
> --
> paul moore
> www.paul-moore.com

-- 
Ondrej Mosnacek <omosnace at redhat dot com>
Software Engineer, Security Technologies
Red Hat, Inc.

Re: [PATCH v2 3/5] selinux: convert cond_av_list to array

[Ondrej Mosnacek]

On Fri, Jan 31, 2020 at 5:17 AM Paul Moore <paul@paul-moore.com> wrote:
>
> On Fri, Jan 17, 2020 at 3:58 AM Ondrej Mosnacek <omosnace@redhat.com> wrote:
> > Since it is fixed-size after allocation and we know the size beforehand,
> > using a plain old array is simpler and more efficient.
> >
> > Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
> > Reviewed-by: Stephen Smalley <sds@tycho.nsa.gov>
> > ---
> >  security/selinux/ss/conditional.c | 125 ++++++++++++------------------
> >  security/selinux/ss/conditional.h |   8 +-
> >  2 files changed, 53 insertions(+), 80 deletions(-)
>
> ...
>
> > diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c
> > index c8a02c9b23ee..b847fd2a6a51 100644
> > --- a/security/selinux/ss/conditional.c
> > +++ b/security/selinux/ss/conditional.c
> > @@ -255,19 +249,17 @@ err:
> >
> >  struct cond_insertf_data {
> >         struct policydb *p;
> > +       struct avtab_node **dst;
> >         struct cond_av_list *other;
> > -       struct cond_av_list *head;
> > -       struct cond_av_list *tail;
> >  };
> >
> >  static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum *d, void *ptr)
> >  {
> >         struct cond_insertf_data *data = ptr;
> >         struct policydb *p = data->p;
> > -       struct cond_av_list *other = data->other, *list, *cur;
> >         struct avtab_node *node_ptr;
> > -       u8 found;
> > -       int rc = -EINVAL;
> > +       u32 i;
> > +       bool found;
> >
> >         /*
> >          * For type rules we have to make certain there aren't any
> > @@ -277,7 +269,7 @@ static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum
> >         if (k->specified & AVTAB_TYPE) {
> >                 if (avtab_search(&p->te_avtab, k)) {
> >                         pr_err("SELinux: type rule already exists outside of a conditional.\n");
> > -                       goto err;
> > +                       return -EINVAL;
> >                 }
> >                 /*
> >                  * If we are reading the false list other will be a pointer to
> > @@ -287,29 +279,29 @@ static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum
> >                  * If we are reading the true list (other == NULL) there shouldn't
> >                  * be any other entries.
> >                  */
> > -               if (other) {
> > +               if (data->other) {
> >                         node_ptr = avtab_search_node(&p->te_cond_avtab, k);
> >                         if (node_ptr) {
> >                                 if (avtab_search_node_next(node_ptr, k->specified)) {
> >                                         pr_err("SELinux: too many conflicting type rules.\n");
> > -                                       goto err;
> > +                                       return -EINVAL;
> >                                 }
> > -                               found = 0;
> > -                               for (cur = other; cur; cur = cur->next) {
> > -                                       if (cur->node == node_ptr) {
> > -                                               found = 1;
> > +                               found = false;
> > +                               for (i = 0; i < data->other->len; i++) {
> > +                                       if (data->other->nodes[i] == node_ptr) {
> > +                                               found = true;
> >                                                 break;
> >                                         }
> >                                 }
>
> Can you explain why you got rid of the "other" variable in this
> function?  It seems like it would be nice in the loop above.

It's probably a result of incremental edits... I agree it looks a bit
nicer with it and it also makes the diff simpler. I'll put it back in
v3.

-- 
Ondrej Mosnacek <omosnace at redhat dot com>
Software Engineer, Security Technologies
Red Hat, Inc.