diff options
| -rw-r--r-- | security/selinux/ss/sidtab.c | 39 | ||||
| -rw-r--r-- | security/selinux/ss/sidtab.h | 2 |
2 files changed, 39 insertions, 2 deletions
diff --git a/security/selinux/ss/sidtab.c b/security/selinux/ss/sidtab.c index e817989764c..5840a35155f 100644 --- a/security/selinux/ss/sidtab.c +++ b/security/selinux/ss/sidtab.c @@ -147,6 +147,17 @@ out: return rc; } +static void sidtab_update_cache(struct sidtab *s, struct sidtab_node *n, int loc) +{ + BUG_ON(loc >= SIDTAB_CACHE_LEN); + + while (loc > 0) { + s->cache[loc] = s->cache[loc - 1]; + loc--; + } + s->cache[0] = n; +} + static inline u32 sidtab_search_context(struct sidtab *s, struct context *context) { @@ -156,14 +167,33 @@ static inline u32 sidtab_search_context(struct sidtab *s, for (i = 0; i < SIDTAB_SIZE; i++) { cur = s->htable[i]; while (cur) { - if (context_cmp(&cur->context, context)) + if (context_cmp(&cur->context, context)) { + sidtab_update_cache(s, cur, SIDTAB_CACHE_LEN - 1); return cur->sid; + } cur = cur->next; } } return 0; } +static inline u32 sidtab_search_cache(struct sidtab *s, struct context *context) +{ + int i; + struct sidtab_node *node; + + for (i = 0; i < SIDTAB_CACHE_LEN; i++) { + node = s->cache[i]; + if (unlikely(!node)) + return 0; + if (context_cmp(&node->context, context)) { + sidtab_update_cache(s, node, i); + return node->sid; + } + } + return 0; +} + int sidtab_context_to_sid(struct sidtab *s, struct context *context, u32 *out_sid) @@ -174,7 +204,9 @@ int sidtab_context_to_sid(struct sidtab *s, *out_sid = SECSID_NULL; - sid = sidtab_search_context(s, context); + sid = sidtab_search_cache(s, context); + if (!sid) + sid = sidtab_search_context(s, context); if (!sid) { spin_lock_irqsave(&s->lock, flags); /* Rescan now that we hold the lock. */ @@ -259,12 +291,15 @@ void sidtab_destroy(struct sidtab *s) void sidtab_set(struct sidtab *dst, struct sidtab *src) { unsigned long flags; + int i; spin_lock_irqsave(&src->lock, flags); dst->htable = src->htable; dst->nel = src->nel; dst->next_sid = src->next_sid; dst->shutdown = 0; + for (i = 0; i < SIDTAB_CACHE_LEN; i++) + dst->cache[i] = NULL; spin_unlock_irqrestore(&src->lock, flags); } diff --git a/security/selinux/ss/sidtab.h b/security/selinux/ss/sidtab.h index 64ea5b1cdea..84dc154d938 100644 --- a/security/selinux/ss/sidtab.h +++ b/security/selinux/ss/sidtab.h @@ -26,6 +26,8 @@ struct sidtab { unsigned int nel; /* number of elements */ unsigned int next_sid; /* next SID to allocate */ unsigned char shutdown; +#define SIDTAB_CACHE_LEN 3 + struct sidtab_node *cache[SIDTAB_CACHE_LEN]; spinlock_t lock; }; |