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, 27 insertions, 1 deletions

diff --git a/security/apparmor/include/audit.h b/security/apparmor/include/audit.h
index 4ba78c2..3868b1e 100644
--- a/security/apparmor/include/audit.h
+++ b/security/apparmor/include/audit.h
@@ -103,7 +103,33 @@ enum aa_ops {
 };
 
 
-/* define a short hand for apparmor_audit_data portion of common_audit_data */
+struct apparmor_audit_data {
+	int error;
+	int op;
+	int type;
+	void *profile;
+	const char *name;
+	const char *info;
+	union {
+		void *target;
+		struct {
+			long pos;
+			void *target;
+		} iface;
+		struct {
+			int rlim;
+			unsigned long max;
+		} rlim;
+		struct {
+			const char *target;
+			u32 request;
+			u32 denied;
+			uid_t ouid;
+		} fs;
+	};
+};
+
+/* define a short hand for apparmor_audit_data structure */
 #define aad apparmor_audit_data
 
 void aa_audit_msg(int type, struct common_audit_data *sa,