LSM: shrink sizeof LSM specific portion of common_audit_data

Linus found that the gigantic size of the common audit data caused a big
perf hit on something as simple as running stat() in a loop.  This patch
requires LSMs to declare the LSM specific portion separately rather than
doing it in a union.  Thus each LSM can be responsible for shrinking their
portion and don't have to pay a penalty just because other LSMs have a
bigger space requirement.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 3 insertions, 1 deletions

diff --git a/security/apparmor/lib.c b/security/apparmor/lib.c
index 9516948041ad..e75829ba0ff9 100644
--- a/security/apparmor/lib.c
+++ b/security/apparmor/lib.c
@@ -65,8 +65,10 @@ void aa_info_message(const char *str)
 {
         if (audit_enabled) {
                 struct common_audit_data sa;
+                struct apparmor_audit_data aad = {0,};
                 COMMON_AUDIT_DATA_INIT(&sa, NONE);
-                sa.aad.info = str;
+                sa.aad = &aad;
+                aad.info = str;
                 aa_audit_msg(AUDIT_APPARMOR_STATUS, &sa, NULL);
         }
         printk(KERN_INFO "AppArmor: %s\n", str);