selinux: reduce the number of calls to synchronize_net() when flushing caches

When flushing the AVC, such as during a policy load, the various
network caches are also flushed, with each making a call to
synchronize_net() which has shown to be expensive in some cases.
This patch consolidates the network cache flushes into a single AVC
callback which only calls synchronize_net() once for each AVC cache
flush.

Reported-by: Jaejyn Shin <flagon22bass@gmail.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>

1 files changed, 1 insertions, 14 deletions

diff --git a/security/selinux/netport.c b/security/selinux/netport.c
index d35379781c2c..73ac6784d091 100644
--- a/security/selinux/netport.c
+++ b/security/selinux/netport.c
@@ -217,7 +217,7 @@ int sel_netport_sid(u8 protocol, u16 pnum, u32 *sid)
  * Remove all entries from the network address table.
  *
  */
-static void sel_netport_flush(void)
+void sel_netport_flush(void)
 {
         unsigned int idx;
         struct sel_netport *port, *port_tmp;
@@ -234,15 +234,6 @@ static void sel_netport_flush(void)
         spin_unlock_bh(&sel_netport_lock);
 }
 
-static int sel_netport_avc_callback(u32 event)
-{
-        if (event == AVC_CALLBACK_RESET) {
-                sel_netport_flush();
-                synchronize_net();
-        }
-        return 0;
-}
-
 static __init int sel_netport_init(void)
 {
         int iter;
@@ -256,10 +247,6 @@ static __init int sel_netport_init(void)
                 sel_netport_hash[iter].size = 0;
         }
 
-        ret = avc_add_callback(sel_netport_avc_callback, AVC_CALLBACK_RESET);
-        if (ret != 0)
-                panic("avc_add_callback() failed, error %d\n", ret);
-
         return ret;
 }