SELinux: drop load_mutex in security_load_policy

We used to protect against races of policy load in security_load_policy
by using the load_mutex.  Since then we have added a new mutex,
sel_mutex, in sel_write_load() which is always held across all calls to
security_load_policy we are covered and can safely just drop this one.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>

1 files changed, 1 insertions, 13 deletions

diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
index f26a8cad06e7..543fd0f31b33 100644
--- a/security/selinux/ss/services.c
+++ b/security/selinux/ss/services.c
@@ -71,7 +71,6 @@ int selinux_policycap_openperm;
 extern const struct selinux_class_perm selinux_class_perm;
 
 static DEFINE_RWLOCK(policy_rwlock);
-static DEFINE_MUTEX(load_mutex);
 
 static struct sidtab sidtab;
 struct policydb policydb;
@@ -1453,17 +1452,13 @@ int security_load_policy(void *data, size_t len)
         int rc = 0;
         struct policy_file file = { data, len }, *fp = &file;
 
-        mutex_lock(&load_mutex);
-
         if (!ss_initialized) {
                 avtab_cache_init();
                 if (policydb_read(&policydb, fp)) {
-                        mutex_unlock(&load_mutex);
                         avtab_cache_destroy();
                         return -EINVAL;
                 }
                 if (policydb_load_isids(&policydb, &sidtab)) {
-                        mutex_unlock(&load_mutex);
                         policydb_destroy(&policydb);
                         avtab_cache_destroy();
                         return -EINVAL;
@@ -1472,7 +1467,6 @@ int security_load_policy(void *data, size_t len)
                 if (validate_classes(&policydb)) {
                         printk(KERN_ERR
                                "SELinux:  the definition of a class is incorrect\n");
-                        mutex_unlock(&load_mutex);
                         sidtab_destroy(&sidtab);
                         policydb_destroy(&policydb);
                         avtab_cache_destroy();
@@ -1482,7 +1476,6 @@ int security_load_policy(void *data, size_t len)
                 policydb_loaded_version = policydb.policyvers;
                 ss_initialized = 1;
                 seqno = ++latest_granting;
-                mutex_unlock(&load_mutex);
                 selinux_complete_init();
                 avc_ss_reset(seqno);
                 selnl_notify_policyload(seqno);
@@ -1495,13 +1488,10 @@ int security_load_policy(void *data, size_t len)
         sidtab_hash_eval(&sidtab, "sids");
 #endif
 
-        if (policydb_read(&newpolicydb, fp)) {
-                mutex_unlock(&load_mutex);
+        if (policydb_read(&newpolicydb, fp))
                 return -EINVAL;
-        }
 
         if (sidtab_init(&newsidtab)) {
-                mutex_unlock(&load_mutex);
                 policydb_destroy(&newpolicydb);
                 return -ENOMEM;
         }
@@ -1549,7 +1539,6 @@ int security_load_policy(void *data, size_t len)
         seqno = ++latest_granting;
         policydb_loaded_version = policydb.policyvers;
         write_unlock_irq(&policy_rwlock);
-        mutex_unlock(&load_mutex);
 
         /* Free the old policydb and SID table. */
         policydb_destroy(&oldpolicydb);
@@ -1563,7 +1552,6 @@ int security_load_policy(void *data, size_t len)
         return 0;
 
 err:
-        mutex_unlock(&load_mutex);
         sidtab_destroy(&newsidtab);
         policydb_destroy(&newpolicydb);
         return rc;