1 files changed, 98 insertions, 137 deletions

diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c
index 2c0e4572cc90..bf87eddfec30 100644
--- a/net/ipv4/cipso_ipv4.c
+++ b/net/ipv4/cipso_ipv4.c
@@ -47,17 +47,7 @@
 #include <asm/bug.h>
 #include <asm/unaligned.h>
 
-struct cipso_v4_domhsh_entry {
-        char *domain;
-        u32 valid;
-        struct list_head list;
-        struct rcu_head rcu;
-};
-
 /* List of available DOI definitions */
-/* XXX - Updates should be minimal so having a single lock for the
- * cipso_v4_doi_list and the cipso_v4_doi_list->dom_list should be
- * okay. */
 /* XXX - This currently assumes a minimal number of different DOIs in use,
  * if in practice there are a lot of different DOIs this list should
  * probably be turned into a hash table or something similar so we
@@ -194,25 +184,6 @@ static void cipso_v4_bitmap_setbit(unsigned char *bitmap,
 }
 
 /**
- * cipso_v4_doi_domhsh_free - Frees a domain list entry
- * @entry: the entry's RCU field
- *
- * Description:
- * This function is designed to be used as a callback to the call_rcu()
- * function so that the memory allocated to a domain list entry can be released
- * safely.
- *
- */
-static void cipso_v4_doi_domhsh_free(struct rcu_head *entry)
-{
-        struct cipso_v4_domhsh_entry *ptr;
-
-        ptr = container_of(entry, struct cipso_v4_domhsh_entry, rcu);
-        kfree(ptr->domain);
-        kfree(ptr);
-}
-
-/**
  * cipso_v4_cache_entry_free - Frees a cache entry
  * @entry: the entry to free
  *
@@ -457,7 +428,7 @@ static struct cipso_v4_doi *cipso_v4_doi_search(u32 doi)
         struct cipso_v4_doi *iter;
 
         list_for_each_entry_rcu(iter, &cipso_v4_doi_list, list)
-                if (iter->doi == doi && iter->valid)
+                if (iter->doi == doi && atomic_read(&iter->refcount))
                         return iter;
         return NULL;
 }
@@ -501,9 +472,8 @@ int cipso_v4_doi_add(struct cipso_v4_doi *doi_def)
                 }
         }
 
-        doi_def->valid = 1;
+        atomic_set(&doi_def->refcount, 1);
         INIT_RCU_HEAD(&doi_def->rcu);
-        INIT_LIST_HEAD(&doi_def->dom_list);
 
         spin_lock(&cipso_v4_doi_list_lock);
         if (cipso_v4_doi_search(doi_def->doi) != NULL)
@@ -519,59 +489,129 @@ doi_add_failure:
 }
 
 /**
+ * cipso_v4_doi_free - Frees a DOI definition
+ * @entry: the entry's RCU field
+ *
+ * Description:
+ * This function frees all of the memory associated with a DOI definition.
+ *
+ */
+void cipso_v4_doi_free(struct cipso_v4_doi *doi_def)
+{
+        if (doi_def == NULL)
+                return;
+
+        switch (doi_def->type) {
+        case CIPSO_V4_MAP_STD:
+                kfree(doi_def->map.std->lvl.cipso);
+                kfree(doi_def->map.std->lvl.local);
+                kfree(doi_def->map.std->cat.cipso);
+                kfree(doi_def->map.std->cat.local);
+                break;
+        }
+        kfree(doi_def);
+}
+
+/**
+ * cipso_v4_doi_free_rcu - Frees a DOI definition via the RCU pointer
+ * @entry: the entry's RCU field
+ *
+ * Description:
+ * This function is designed to be used as a callback to the call_rcu()
+ * function so that the memory allocated to the DOI definition can be released
+ * safely.
+ *
+ */
+static void cipso_v4_doi_free_rcu(struct rcu_head *entry)
+{
+        struct cipso_v4_doi *doi_def;
+
+        doi_def = container_of(entry, struct cipso_v4_doi, rcu);
+        cipso_v4_doi_free(doi_def);
+}
+
+/**
  * cipso_v4_doi_remove - Remove an existing DOI from the CIPSO protocol engine
  * @doi: the DOI value
  * @audit_secid: the LSM secid to use in the audit message
- * @callback: the DOI cleanup/free callback
  *
  * Description:
- * Removes a DOI definition from the CIPSO engine, @callback is called to
- * free any memory.  The NetLabel routines will be called to release their own
- * LSM domain mappings as well as our own domain list.  Returns zero on
- * success and negative values on failure.
+ * Removes a DOI definition from the CIPSO engine.  The NetLabel routines will
+ * be called to release their own LSM domain mappings as well as our own
+ * domain list.  Returns zero on success and negative values on failure.
  *
  */
-int cipso_v4_doi_remove(u32 doi,
-                        struct netlbl_audit *audit_info,
-                        void (*callback) (struct rcu_head * head))
+int cipso_v4_doi_remove(u32 doi, struct netlbl_audit *audit_info)
 {
         struct cipso_v4_doi *doi_def;
-        struct cipso_v4_domhsh_entry *dom_iter;
 
         spin_lock(&cipso_v4_doi_list_lock);
         doi_def = cipso_v4_doi_search(doi);
-        if (doi_def != NULL) {
-                doi_def->valid = 0;
-                list_del_rcu(&doi_def->list);
+        if (doi_def == NULL) {
                 spin_unlock(&cipso_v4_doi_list_lock);
-                rcu_read_lock();
-                list_for_each_entry_rcu(dom_iter, &doi_def->dom_list, list)
-                        if (dom_iter->valid)
-                                netlbl_cfg_map_del(dom_iter->domain,
-                                                   audit_info);
-                rcu_read_unlock();
-                cipso_v4_cache_invalidate();
-                call_rcu(&doi_def->rcu, callback);
-                return 0;
+                return -ENOENT;
+        }
+        if (!atomic_dec_and_test(&doi_def->refcount)) {
+                spin_unlock(&cipso_v4_doi_list_lock);
+                return -EBUSY;
         }
+        list_del_rcu(&doi_def->list);
         spin_unlock(&cipso_v4_doi_list_lock);
 
-        return -ENOENT;
+        cipso_v4_cache_invalidate();
+        call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu);
+
+        return 0;
 }
 
 /**
- * cipso_v4_doi_getdef - Returns a pointer to a valid DOI definition
+ * cipso_v4_doi_getdef - Returns a reference to a valid DOI definition
  * @doi: the DOI value
  *
  * Description:
  * Searches for a valid DOI definition and if one is found it is returned to
  * the caller.  Otherwise NULL is returned.  The caller must ensure that
- * rcu_read_lock() is held while accessing the returned definition.
+ * rcu_read_lock() is held while accessing the returned definition and the DOI
+ * definition reference count is decremented when the caller is done.
  *
  */
 struct cipso_v4_doi *cipso_v4_doi_getdef(u32 doi)
 {
-        return cipso_v4_doi_search(doi);
+        struct cipso_v4_doi *doi_def;
+
+        rcu_read_lock();
+        doi_def = cipso_v4_doi_search(doi);
+        if (doi_def == NULL)
+                goto doi_getdef_return;
+        if (!atomic_inc_not_zero(&doi_def->refcount))
+                doi_def = NULL;
+
+doi_getdef_return:
+        rcu_read_unlock();
+        return doi_def;
+}
+
+/**
+ * cipso_v4_doi_putdef - Releases a reference for the given DOI definition
+ * @doi_def: the DOI definition
+ *
+ * Description:
+ * Releases a DOI definition reference obtained from cipso_v4_doi_getdef().
+ *
+ */
+void cipso_v4_doi_putdef(struct cipso_v4_doi *doi_def)
+{
+        if (doi_def == NULL)
+                return;
+
+        if (!atomic_dec_and_test(&doi_def->refcount))
+                return;
+        spin_lock(&cipso_v4_doi_list_lock);
+        list_del_rcu(&doi_def->list);
+        spin_unlock(&cipso_v4_doi_list_lock);
+
+        cipso_v4_cache_invalidate();
+        call_rcu(&doi_def->rcu, cipso_v4_doi_free_rcu);
 }
 
 /**
@@ -597,7 +637,7 @@ int cipso_v4_doi_walk(u32 *skip_cnt,
 
         rcu_read_lock();
         list_for_each_entry_rcu(iter_doi, &cipso_v4_doi_list, list)
-                if (iter_doi->valid) {
+                if (atomic_read(&iter_doi->refcount) > 0) {
                         if (doi_cnt++ < *skip_cnt)
                                 continue;
                         ret_val = callback(iter_doi, cb_arg);
@@ -613,85 +653,6 @@ doi_walk_return:
         return ret_val;
 }
 
-/**
- * cipso_v4_doi_domhsh_add - Adds a domain entry to a DOI definition
- * @doi_def: the DOI definition
- * @domain: the domain to add
- *
- * Description:
- * Adds the @domain to the DOI specified by @doi_def, this function
- * should only be called by external functions (i.e. NetLabel).  This function
- * does allocate memory.  Returns zero on success, negative values on failure.
- *
- */
-int cipso_v4_doi_domhsh_add(struct cipso_v4_doi *doi_def, const char *domain)
-{
-        struct cipso_v4_domhsh_entry *iter;
-        struct cipso_v4_domhsh_entry *new_dom;
-
-        new_dom = kzalloc(sizeof(*new_dom), GFP_KERNEL);
-        if (new_dom == NULL)
-                return -ENOMEM;
-        if (domain) {
-                new_dom->domain = kstrdup(domain, GFP_KERNEL);
-                if (new_dom->domain == NULL) {
-                        kfree(new_dom);
-                        return -ENOMEM;
-                }
-        }
-        new_dom->valid = 1;
-        INIT_RCU_HEAD(&new_dom->rcu);
-
-        spin_lock(&cipso_v4_doi_list_lock);
-        list_for_each_entry(iter, &doi_def->dom_list, list)
-                if (iter->valid &&
-                    ((domain != NULL && iter->domain != NULL &&
-                      strcmp(iter->domain, domain) == 0) ||
-                     (domain == NULL && iter->domain == NULL))) {
-                        spin_unlock(&cipso_v4_doi_list_lock);
-                        kfree(new_dom->domain);
-                        kfree(new_dom);
-                        return -EEXIST;
-                }
-        list_add_tail_rcu(&new_dom->list, &doi_def->dom_list);
-        spin_unlock(&cipso_v4_doi_list_lock);
-
-        return 0;
-}
-
-/**
- * cipso_v4_doi_domhsh_remove - Removes a domain entry from a DOI definition
- * @doi_def: the DOI definition
- * @domain: the domain to remove
- *
- * Description:
- * Removes the @domain from the DOI specified by @doi_def, this function
- * should only be called by external functions (i.e. NetLabel).   Returns zero
- * on success and negative values on error.
- *
- */
-int cipso_v4_doi_domhsh_remove(struct cipso_v4_doi *doi_def,
-                               const char *domain)
-{
-        struct cipso_v4_domhsh_entry *iter;
-
-        spin_lock(&cipso_v4_doi_list_lock);
-        list_for_each_entry(iter, &doi_def->dom_list, list)
-                if (iter->valid &&
-                    ((domain != NULL && iter->domain != NULL &&
-                      strcmp(iter->domain, domain) == 0) ||
-                     (domain == NULL && iter->domain == NULL))) {
-                        iter->valid = 0;
-                        list_del_rcu(&iter->list);
-                        spin_unlock(&cipso_v4_doi_list_lock);
-                        call_rcu(&iter->rcu, cipso_v4_doi_domhsh_free);
-                        return 0;
-                }
-        spin_unlock(&cipso_v4_doi_list_lock);
-
-        return -ENOENT;
-}
-
 /*
  * Label Mapping Functions
  */