1 files changed, 103 insertions, 156 deletions

diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c
index 70c378ee1a2f..939a74fd8fb4 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)
@@ -85,90 +86,76 @@ 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)
+static 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);
+	new_state = cond_evaluate_expr(p, &node->expr);
 	if (new_state != node->cur_state) {
 		node->cur_state = new_state;
 		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;
 		}
 	}
-	return 0;
 }
 
-int cond_policydb_init(struct policydb *p)
+void evaluate_cond_nodes(struct policydb *p)
 {
-	int rc;
+	u32 i;
 
-	p->bool_val_to_struct = NULL;
-	p->cond_list = NULL;
-
-	rc = avtab_init(&p->te_cond_avtab);
-	if (rc)
-		return rc;
-
-	return 0;
+	for (i = 0; i < p->cond_list_len; i++)
+		evaluate_cond_node(p, &p->cond_list[i]);
 }
 
-static void cond_av_list_destroy(struct cond_av_list *list)
+void cond_policydb_init(struct policydb *p)
 {
-	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);
-	}
+	p->bool_val_to_struct = NULL;
+	p->cond_list = NULL;
+	p->cond_list_len = 0;
+
+	avtab_init(&p->te_cond_avtab);
 }
 
 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);
-	}
-	cond_av_list_destroy(node->true_list);
-	cond_av_list_destroy(node->false_list);
-	kfree(node);
+	kfree(node->expr.nodes);
+	/* 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 cond_node *list)
+static void cond_list_destroy(struct policydb *p)
 {
-	struct cond_node *next, *cur;
-
-	if (list == NULL)
-		return;
+	u32 i;
 
-	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)
@@ -260,19 +247,18 @@ 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 cond_av_list *other = data->other;
 	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
@@ -282,7 +268,7 @@ 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
@@ -297,24 +283,24 @@ static int cond_insertf(struct avtab *a, struct avtab_key *k, struct avtab_datum
 			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 < other->len; i++) {
+					if (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;
 			}
 		}
 	}
@@ -322,39 +308,22 @@ 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;
@@ -363,22 +332,28 @@ 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;
 }
 
-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");
@@ -395,49 +370,43 @@ 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);
 	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;
@@ -448,7 +417,6 @@ err:
 
 int cond_read_list(struct policydb *p, void *fp)
 {
-	struct cond_node *node, *last = NULL;
 	__le32 buf[1];
 	u32 i, len;
 	int rc;
@@ -459,29 +427,24 @@ 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;
+	p->cond_list_len = len;
 
-		rc = cond_read_node(p, node, fp);
+	for (i = 0; i < len; i++) {
+		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;
 	}
 	return 0;
 err:
-	cond_list_destroy(p->cond_list);
+	cond_list_destroy(p);
 	p->cond_list = NULL;
 	return rc;
 }
@@ -522,24 +485,16 @@ 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;
 	}
@@ -550,59 +505,51 @@ 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;
 	}
 
-	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;
 
 	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;
 	}