apparmor: move task from common_audit_data to apparmor_audit_data

apparmor is the only LSM that uses the common_audit_data tsk field.
Instead of making all LSMs pay for the stack space move the aa usage into
the apparmor_audit_data.
Signed-off-by: Eric Paris <eparis@redhat.com>

security/apparmor/audit.c

@@ -111,7 +111,7 @@ static const char *const aa_audit_type[] = {
 static void audit_pre(struct audit_buffer *ab, void *ca)
 {
 	struct common_audit_data *sa = ca;
-	struct task_struct *tsk = sa->tsk ? sa->tsk : current;
+	struct task_struct *tsk = sa->aad->tsk ? sa->aad->tsk : current;
 
 	if (aa_g_audit_header) {
 		audit_log_format(ab, "apparmor=");
@@ -149,6 +149,12 @@ static void audit_pre(struct audit_buffer *ab, void *ca)
 		audit_log_format(ab, " name=");
 		audit_log_untrustedstring(ab, sa->aad->name);
 	}
+
+	if (sa->aad->tsk) {
+		audit_log_format(ab, " pid=%d comm=", tsk->pid);
+		audit_log_untrustedstring(ab, tsk->comm);
+	}
+
 }
 
 /**
@@ -205,7 +211,8 @@ int aa_audit(int type, struct aa_profile *profile, gfp_t gfp,
 	aa_audit_msg(type, sa, cb);
 
 	if (sa->aad->type == AUDIT_APPARMOR_KILL)
-		(void)send_sig_info(SIGKILL, NULL, sa->tsk ? sa->tsk : current);
+		(void)send_sig_info(SIGKILL, NULL,
+				    sa->aad->tsk ?  sa->aad->tsk : current);
 
 	if (sa->aad->type == AUDIT_APPARMOR_ALLOWED)
 		return complain_error(sa->aad->error);

security/apparmor/capability.c

@@ -67,8 +67,8 @@ static int audit_caps(struct aa_profile *profile, struct task_struct *task,
 	struct apparmor_audit_data aad = {0,};
 	COMMON_AUDIT_DATA_INIT(&sa, LSM_AUDIT_DATA_CAP);
 	sa.aad = &aad;
-	sa.tsk = task;
 	sa.u.cap = cap;
+	sa.aad->tsk = task;
 	sa.aad->op = OP_CAPABLE;
 	sa.aad->error = error;
 

security/apparmor/include/audit.h

@@ -110,6 +110,7 @@ struct apparmor_audit_data {
 	void *profile;
 	const char *name;
 	const char *info;
+	struct task_struct *tsk;
 	union {
 		void *target;
 		struct {