aboutsummaryrefslogtreecommitdiffstats
path: root/security/selinux/netnode.c
diff options
context:
space:
mode:
authorPaul Moore <paul.moore@hp.com>2008-04-25 15:03:34 -0400
committerJames Morris <jmorris@namei.org>2008-04-28 09:36:23 +1000
commita639e7ca8e8282b75be2724a28bfc788aa3bb156 (patch)
tree1a3308a354874ce1bc6b3c9ec71427a5204da7b5 /security/selinux/netnode.c
parent7b41b1733ca1d3278c8eb891e17905d7d54f5bfa (diff)
downloadmrst-s0i3-test-a639e7ca8e8282b75be2724a28bfc788aa3bb156.tar.gz
mrst-s0i3-test-a639e7ca8e8282b75be2724a28bfc788aa3bb156.tar.xz
mrst-s0i3-test-a639e7ca8e8282b75be2724a28bfc788aa3bb156.zip
SELinux: Made netnode cache adds faster
When adding new entries to the network node cache we would walk the entire hash bucket to make sure we didn't cross a threshold (done to bound the cache size). This isn't a very quick or elegant solution for something which is supposed to be quick-ish so add a counter to each hash bucket to track the size of the bucket and eliminate the need to walk the entire bucket list on each add. Signed-off-by: Paul Moore <paul.moore@hp.com> Signed-off-by: James Morris <jmorris@namei.org>
Diffstat (limited to 'security/selinux/netnode.c')
-rw-r--r--security/selinux/netnode.c104
1 files changed, 49 insertions, 55 deletions
diff --git a/security/selinux/netnode.c b/security/selinux/netnode.c
index 2edc4c5e0c6..b6ccd09379f 100644
--- a/security/selinux/netnode.c
+++ b/security/selinux/netnode.c
@@ -40,11 +40,17 @@
#include <net/ipv6.h>
#include <asm/bug.h>
+#include "netnode.h"
#include "objsec.h"
#define SEL_NETNODE_HASH_SIZE 256
#define SEL_NETNODE_HASH_BKT_LIMIT 16
+struct sel_netnode_bkt {
+ unsigned int size;
+ struct list_head list;
+};
+
struct sel_netnode {
struct netnode_security_struct nsec;
@@ -60,7 +66,7 @@ struct sel_netnode {
static LIST_HEAD(sel_netnode_list);
static DEFINE_SPINLOCK(sel_netnode_lock);
-static struct list_head sel_netnode_hash[SEL_NETNODE_HASH_SIZE];
+static struct sel_netnode_bkt sel_netnode_hash[SEL_NETNODE_HASH_SIZE];
/**
* sel_netnode_free - Frees a node entry
@@ -87,7 +93,7 @@ static void sel_netnode_free(struct rcu_head *p)
* the bucket number for the given IP address.
*
*/
-static u32 sel_netnode_hashfn_ipv4(__be32 addr)
+static unsigned int sel_netnode_hashfn_ipv4(__be32 addr)
{
/* at some point we should determine if the mismatch in byte order
* affects the hash function dramatically */
@@ -103,7 +109,7 @@ static u32 sel_netnode_hashfn_ipv4(__be32 addr)
* the bucket number for the given IP address.
*
*/
-static u32 sel_netnode_hashfn_ipv6(const struct in6_addr *addr)
+static unsigned int sel_netnode_hashfn_ipv6(const struct in6_addr *addr)
{
/* just hash the least significant 32 bits to keep things fast (they
* are the most likely to be different anyway), we can revisit this
@@ -123,7 +129,7 @@ static u32 sel_netnode_hashfn_ipv6(const struct in6_addr *addr)
*/
static struct sel_netnode *sel_netnode_find(const void *addr, u16 family)
{
- u32 idx;
+ unsigned int idx;
struct sel_netnode *node;
switch (family) {
@@ -137,7 +143,7 @@ static struct sel_netnode *sel_netnode_find(const void *addr, u16 family)
BUG();
}
- list_for_each_entry_rcu(node, &sel_netnode_hash[idx], list)
+ list_for_each_entry_rcu(node, &sel_netnode_hash[idx].list, list)
if (node->nsec.family == family)
switch (family) {
case PF_INET:
@@ -159,15 +165,12 @@ static struct sel_netnode *sel_netnode_find(const void *addr, u16 family)
* @node: the new node record
*
* Description:
- * Add a new node record to the network address hash table. Returns zero on
- * success, negative values on failure.
+ * Add a new node record to the network address hash table.
*
*/
-static int sel_netnode_insert(struct sel_netnode *node)
+static void sel_netnode_insert(struct sel_netnode *node)
{
- u32 idx;
- u32 count = 0;
- struct sel_netnode *iter;
+ unsigned int idx;
switch (node->nsec.family) {
case PF_INET:
@@ -179,32 +182,21 @@ static int sel_netnode_insert(struct sel_netnode *node)
default:
BUG();
}
- list_add_rcu(&node->list, &sel_netnode_hash[idx]);
+
+ INIT_RCU_HEAD(&node->rcu);
/* we need to impose a limit on the growth of the hash table so check
* this bucket to make sure it is within the specified bounds */
- list_for_each_entry(iter, &sel_netnode_hash[idx], list)
- if (++count > SEL_NETNODE_HASH_BKT_LIMIT) {
- list_del_rcu(&iter->list);
- call_rcu(&iter->rcu, sel_netnode_free);
- break;
- }
-
- return 0;
-}
-
-/**
- * sel_netnode_destroy - Remove a node record from the table
- * @node: the existing node record
- *
- * Description:
- * Remove an existing node record from the network address table.
- *
- */
-static void sel_netnode_destroy(struct sel_netnode *node)
-{
- list_del_rcu(&node->list);
- call_rcu(&node->rcu, sel_netnode_free);
+ list_add_rcu(&node->list, &sel_netnode_hash[idx].list);
+ if (sel_netnode_hash[idx].size == SEL_NETNODE_HASH_BKT_LIMIT) {
+ struct sel_netnode *tail;
+ tail = list_entry(
+ rcu_dereference(sel_netnode_hash[idx].list.prev),
+ struct sel_netnode, list);
+ list_del_rcu(&tail->list);
+ call_rcu(&tail->rcu, sel_netnode_free);
+ } else
+ sel_netnode_hash[idx].size++;
}
/**
@@ -222,7 +214,7 @@ static void sel_netnode_destroy(struct sel_netnode *node)
*/
static int sel_netnode_sid_slow(void *addr, u16 family, u32 *sid)
{
- int ret;
+ int ret = -ENOMEM;
struct sel_netnode *node;
struct sel_netnode *new = NULL;
@@ -230,25 +222,21 @@ static int sel_netnode_sid_slow(void *addr, u16 family, u32 *sid)
node = sel_netnode_find(addr, family);
if (node != NULL) {
*sid = node->nsec.sid;
- ret = 0;
- goto out;
+ spin_unlock_bh(&sel_netnode_lock);
+ return 0;
}
new = kzalloc(sizeof(*new), GFP_ATOMIC);
- if (new == NULL) {
- ret = -ENOMEM;
+ if (new == NULL)
goto out;
- }
switch (family) {
case PF_INET:
ret = security_node_sid(PF_INET,
- addr, sizeof(struct in_addr),
- &new->nsec.sid);
+ addr, sizeof(struct in_addr), sid);
new->nsec.addr.ipv4 = *(__be32 *)addr;
break;
case PF_INET6:
ret = security_node_sid(PF_INET6,
- addr, sizeof(struct in6_addr),
- &new->nsec.sid);
+ addr, sizeof(struct in6_addr), sid);
ipv6_addr_copy(&new->nsec.addr.ipv6, addr);
break;
default:
@@ -256,11 +244,10 @@ static int sel_netnode_sid_slow(void *addr, u16 family, u32 *sid)
}
if (ret != 0)
goto out;
+
new->nsec.family = family;
- ret = sel_netnode_insert(new);
- if (ret != 0)
- goto out;
- *sid = new->nsec.sid;
+ new->nsec.sid = *sid;
+ sel_netnode_insert(new);
out:
spin_unlock_bh(&sel_netnode_lock);
@@ -312,13 +299,18 @@ int sel_netnode_sid(void *addr, u16 family, u32 *sid)
*/
static void sel_netnode_flush(void)
{
- u32 idx;
- struct sel_netnode *node;
+ unsigned int idx;
+ struct sel_netnode *node, *node_tmp;
spin_lock_bh(&sel_netnode_lock);
- for (idx = 0; idx < SEL_NETNODE_HASH_SIZE; idx++)
- list_for_each_entry(node, &sel_netnode_hash[idx], list)
- sel_netnode_destroy(node);
+ for (idx = 0; idx < SEL_NETNODE_HASH_SIZE; idx++) {
+ list_for_each_entry_safe(node, node_tmp,
+ &sel_netnode_hash[idx].list, list) {
+ list_del_rcu(&node->list);
+ call_rcu(&node->rcu, sel_netnode_free);
+ }
+ sel_netnode_hash[idx].size = 0;
+ }
spin_unlock_bh(&sel_netnode_lock);
}
@@ -340,8 +332,10 @@ static __init int sel_netnode_init(void)
if (!selinux_enabled)
return 0;
- for (iter = 0; iter < SEL_NETNODE_HASH_SIZE; iter++)
- INIT_LIST_HEAD(&sel_netnode_hash[iter]);
+ for (iter = 0; iter < SEL_NETNODE_HASH_SIZE; iter++) {
+ INIT_LIST_HEAD(&sel_netnode_hash[iter].list);
+ sel_netnode_hash[iter].size = 0;
+ }
ret = avc_add_callback(sel_netnode_avc_callback, AVC_CALLBACK_RESET,
SECSID_NULL, SECSID_NULL, SECCLASS_NULL, 0);