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Diffstat (limited to 'security/selinux/ss/avtab.c')
-rw-r--r--security/selinux/ss/avtab.c91
1 files changed, 65 insertions, 26 deletions
diff --git a/security/selinux/ss/avtab.c b/security/selinux/ss/avtab.c
index 85705eb289e..7551af1f789 100644
--- a/security/selinux/ss/avtab.c
+++ b/security/selinux/ss/avtab.c
@@ -12,24 +12,25 @@
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, version 2.
+ *
+ * Updated: Yuichi Nakamura <ynakam@hitachisoft.jp>
+ * Tuned number of hash slots for avtab to reduce memory usage
*/
#include <linux/kernel.h>
#include <linux/slab.h>
-#include <linux/vmalloc.h>
#include <linux/errno.h>
-
#include "avtab.h"
#include "policydb.h"
-#define AVTAB_HASH(keyp) \
-((keyp->target_class + \
- (keyp->target_type << 2) + \
- (keyp->source_type << 9)) & \
- AVTAB_HASH_MASK)
-
static struct kmem_cache *avtab_node_cachep;
+static inline int avtab_hash(struct avtab_key *keyp, u16 mask)
+{
+ return ((keyp->target_class + (keyp->target_type << 2) +
+ (keyp->source_type << 9)) & mask);
+}
+
static struct avtab_node*
avtab_insert_node(struct avtab *h, int hvalue,
struct avtab_node * prev, struct avtab_node * cur,
@@ -59,10 +60,10 @@ static int avtab_insert(struct avtab *h, struct avtab_key *key, struct avtab_dat
struct avtab_node *prev, *cur, *newnode;
u16 specified = key->specified & ~(AVTAB_ENABLED|AVTAB_ENABLED_OLD);
- if (!h)
+ if (!h || !h->htable)
return -EINVAL;
- hvalue = AVTAB_HASH(key);
+ hvalue = avtab_hash(key, h->mask);
for (prev = NULL, cur = h->htable[hvalue];
cur;
prev = cur, cur = cur->next) {
@@ -100,9 +101,9 @@ avtab_insert_nonunique(struct avtab * h, struct avtab_key * key, struct avtab_da
struct avtab_node *prev, *cur, *newnode;
u16 specified = key->specified & ~(AVTAB_ENABLED|AVTAB_ENABLED_OLD);
- if (!h)
+ if (!h || !h->htable)
return NULL;
- hvalue = AVTAB_HASH(key);
+ hvalue = avtab_hash(key, h->mask);
for (prev = NULL, cur = h->htable[hvalue];
cur;
prev = cur, cur = cur->next) {
@@ -132,10 +133,10 @@ struct avtab_datum *avtab_search(struct avtab *h, struct avtab_key *key)
struct avtab_node *cur;
u16 specified = key->specified & ~(AVTAB_ENABLED|AVTAB_ENABLED_OLD);
- if (!h)
+ if (!h || !h->htable)
return NULL;
- hvalue = AVTAB_HASH(key);
+ hvalue = avtab_hash(key, h->mask);
for (cur = h->htable[hvalue]; cur; cur = cur->next) {
if (key->source_type == cur->key.source_type &&
key->target_type == cur->key.target_type &&
@@ -167,10 +168,10 @@ avtab_search_node(struct avtab *h, struct avtab_key *key)
struct avtab_node *cur;
u16 specified = key->specified & ~(AVTAB_ENABLED|AVTAB_ENABLED_OLD);
- if (!h)
+ if (!h || !h->htable)
return NULL;
- hvalue = AVTAB_HASH(key);
+ hvalue = avtab_hash(key, h->mask);
for (cur = h->htable[hvalue]; cur; cur = cur->next) {
if (key->source_type == cur->key.source_type &&
key->target_type == cur->key.target_type &&
@@ -228,7 +229,7 @@ void avtab_destroy(struct avtab *h)
if (!h || !h->htable)
return;
- for (i = 0; i < AVTAB_SIZE; i++) {
+ for (i = 0; i < h->nslot; i++) {
cur = h->htable[i];
while (cur != NULL) {
temp = cur;
@@ -237,32 +238,63 @@ void avtab_destroy(struct avtab *h)
}
h->htable[i] = NULL;
}
- vfree(h->htable);
+ kfree(h->htable);
h->htable = NULL;
+ h->nslot = 0;
+ h->mask = 0;
}
-
int avtab_init(struct avtab *h)
{
- int i;
+ h->htable = NULL;
+ h->nel = 0;
+ return 0;
+}
+
+int avtab_alloc(struct avtab *h, u32 nrules)
+{
+ u16 mask = 0;
+ u32 shift = 0;
+ u32 work = nrules;
+ u32 nslot = 0;
+
+ if (nrules == 0)
+ goto avtab_alloc_out;
- h->htable = vmalloc(sizeof(*(h->htable)) * AVTAB_SIZE);
+ while (work) {
+ work = work >> 1;
+ shift++;
+ }
+ if (shift > 2)
+ shift = shift - 2;
+ nslot = 1 << shift;
+ if (nslot > MAX_AVTAB_SIZE)
+ nslot = MAX_AVTAB_SIZE;
+ mask = nslot - 1;
+
+ h->htable = kcalloc(nslot, sizeof(*(h->htable)), GFP_KERNEL);
if (!h->htable)
return -ENOMEM;
- for (i = 0; i < AVTAB_SIZE; i++)
- h->htable[i] = NULL;
+
+ avtab_alloc_out:
h->nel = 0;
+ h->nslot = nslot;
+ h->mask = mask;
+ printk(KERN_DEBUG "SELinux:%d avtab hash slots allocated."
+ "Num of rules:%d\n", h->nslot, nrules);
return 0;
}
void avtab_hash_eval(struct avtab *h, char *tag)
{
int i, chain_len, slots_used, max_chain_len;
+ unsigned long long chain2_len_sum;
struct avtab_node *cur;
slots_used = 0;
max_chain_len = 0;
- for (i = 0; i < AVTAB_SIZE; i++) {
+ chain2_len_sum = 0;
+ for (i = 0; i < h->nslot; i++) {
cur = h->htable[i];
if (cur) {
slots_used++;
@@ -274,12 +306,14 @@ void avtab_hash_eval(struct avtab *h, char *tag)
if (chain_len > max_chain_len)
max_chain_len = chain_len;
+ chain2_len_sum += chain_len * chain_len;
}
}
printk(KERN_DEBUG "%s: %d entries and %d/%d buckets used, longest "
- "chain length %d\n", tag, h->nel, slots_used, AVTAB_SIZE,
- max_chain_len);
+ "chain length %d sum of chain length^2 %Lu\n",
+ tag, h->nel, slots_used, h->nslot, max_chain_len,
+ chain2_len_sum);
}
static uint16_t spec_order[] = {
@@ -419,6 +453,11 @@ int avtab_read(struct avtab *a, void *fp, u32 vers)
rc = -EINVAL;
goto bad;
}
+
+ rc = avtab_alloc(a, nel);
+ if (rc)
+ goto bad;
+
for (i = 0; i < nel; i++) {
rc = avtab_read_item(fp,vers, a, avtab_insertf, NULL);
if (rc) {