selinux: convert cond_av_list to array
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>
Signed-off-by: Paul Moore <paul@paul-moore.com>
diff --git a/security/selinux/ss/conditional.c b/security/selinux/ss/conditional.c
index e6d203b..82002b9 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 +249,18 @@ int cond_read_bool(struct policydb *p, struct hashtab *h, void *fp)
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
@@ -277,7 +270,7 @@ 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
@@ -292,24 +285,24 @@ 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;
}
}
}
@@ -317,39 +310,22 @@ 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;
+ return -ENOMEM;
}
- list = kzalloc(sizeof(*list), GFP_KERNEL);
- if (!list) {
- rc = -ENOMEM;
- goto err;
- }
-
- 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 +334,24 @@ 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 +414,7 @@ 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 +493,16 @@ 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 +539,10 @@ 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;