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>
diff --git a/security/apparmor/audit.c b/security/apparmor/audit.c
index 5ff6777..23f7eb6 100644
--- a/security/apparmor/audit.c
+++ b/security/apparmor/audit.c
@@ -115,23 +115,23 @@
 
 	if (aa_g_audit_header) {
 		audit_log_format(ab, "apparmor=");
-		audit_log_string(ab, aa_audit_type[sa->aad.type]);
+		audit_log_string(ab, aa_audit_type[sa->aad->type]);
 	}
 
-	if (sa->aad.op) {
+	if (sa->aad->op) {
 		audit_log_format(ab, " operation=");
-		audit_log_string(ab, op_table[sa->aad.op]);
+		audit_log_string(ab, op_table[sa->aad->op]);
 	}
 
-	if (sa->aad.info) {
+	if (sa->aad->info) {
 		audit_log_format(ab, " info=");
-		audit_log_string(ab, sa->aad.info);
-		if (sa->aad.error)
-			audit_log_format(ab, " error=%d", sa->aad.error);
+		audit_log_string(ab, sa->aad->info);
+		if (sa->aad->error)
+			audit_log_format(ab, " error=%d", sa->aad->error);
 	}
 
-	if (sa->aad.profile) {
-		struct aa_profile *profile = sa->aad.profile;
+	if (sa->aad->profile) {
+		struct aa_profile *profile = sa->aad->profile;
 		pid_t pid;
 		rcu_read_lock();
 		pid = rcu_dereference(tsk->real_parent)->pid;
@@ -145,9 +145,9 @@
 		audit_log_untrustedstring(ab, profile->base.hname);
 	}
 
-	if (sa->aad.name) {
+	if (sa->aad->name) {
 		audit_log_format(ab, " name=");
-		audit_log_untrustedstring(ab, sa->aad.name);
+		audit_log_untrustedstring(ab, sa->aad->name);
 	}
 }
 
@@ -159,7 +159,7 @@
 void aa_audit_msg(int type, struct common_audit_data *sa,
 		  void (*cb) (struct audit_buffer *, void *))
 {
-	sa->aad.type = type;
+	sa->aad->type = type;
 	sa->lsm_pre_audit = audit_pre;
 	sa->lsm_post_audit = cb;
 	common_lsm_audit(sa);
@@ -184,7 +184,7 @@
 	BUG_ON(!profile);
 
 	if (type == AUDIT_APPARMOR_AUTO) {
-		if (likely(!sa->aad.error)) {
+		if (likely(!sa->aad->error)) {
 			if (AUDIT_MODE(profile) != AUDIT_ALL)
 				return 0;
 			type = AUDIT_APPARMOR_AUDIT;
@@ -196,21 +196,21 @@
 	if (AUDIT_MODE(profile) == AUDIT_QUIET ||
 	    (type == AUDIT_APPARMOR_DENIED &&
 	     AUDIT_MODE(profile) == AUDIT_QUIET))
-		return sa->aad.error;
+		return sa->aad->error;
 
 	if (KILL_MODE(profile) && type == AUDIT_APPARMOR_DENIED)
 		type = AUDIT_APPARMOR_KILL;
 
 	if (!unconfined(profile))
-		sa->aad.profile = profile;
+		sa->aad->profile = profile;
 
 	aa_audit_msg(type, sa, cb);
 
-	if (sa->aad.type == AUDIT_APPARMOR_KILL)
+	if (sa->aad->type == AUDIT_APPARMOR_KILL)
 		(void)send_sig_info(SIGKILL, NULL, sa->tsk ? sa->tsk : current);
 
-	if (sa->aad.type == AUDIT_APPARMOR_ALLOWED)
-		return complain_error(sa->aad.error);
+	if (sa->aad->type == AUDIT_APPARMOR_ALLOWED)
+		return complain_error(sa->aad->error);
 
-	return sa->aad.error;
+	return sa->aad->error;
 }