audit: change context data from secid to lsm_prop

Change the LSM data stored in the audit transactions from a secid
to an LSM prop. This is done in struct audit_context and struct
audit_aux_data_pids. Several cases of scaffolding can be removed.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
[PM: subj line tweak]
Signed-off-by: Paul Moore <paul@paul-moore.com>

Author: cschaufler

kernel/audit.h

@@ -144,7 +144,7 @@ struct audit_context {
 	kuid_t		    target_auid;
 	kuid_t		    target_uid;
 	unsigned int	    target_sessionid;
-	u32		    target_sid;
+	struct lsm_prop	    target_ref;
 	char		    target_comm[TASK_COMM_LEN];
 
 	struct audit_tree_refs *trees, *first_trees;

kernel/auditfilter.c

@@ -1370,7 +1370,6 @@ int audit_filter(int msgtype, unsigned int listtype)
 			case AUDIT_SUBJ_SEN:
 			case AUDIT_SUBJ_CLR:
 				if (f->lsm_rule) {
-					/* scaffolding */
 					security_current_getlsmprop_subj(&prop);
 					result = security_audit_rule_match(
 						   &prop, f->type, f->op,

kernel/auditsc.c

@@ -100,7 +100,7 @@ struct audit_aux_data_pids {
 	kuid_t			target_auid[AUDIT_AUX_PIDS];
 	kuid_t			target_uid[AUDIT_AUX_PIDS];
 	unsigned int		target_sessionid[AUDIT_AUX_PIDS];
-	u32			target_sid[AUDIT_AUX_PIDS];
+	struct lsm_prop		target_ref[AUDIT_AUX_PIDS];
 	char 			target_comm[AUDIT_AUX_PIDS][TASK_COMM_LEN];
 	int			pid_count;
 };
@@ -1019,7 +1019,7 @@ static void audit_reset_context(struct audit_context *ctx)
 	ctx->target_pid = 0;
 	ctx->target_auid = ctx->target_uid = KUIDT_INIT(0);
 	ctx->target_sessionid = 0;
-	ctx->target_sid = 0;
+	lsmprop_init(&ctx->target_ref);
 	ctx->target_comm[0] = '\0';
 	unroll_tree_refs(ctx, NULL, 0);
 	WARN_ON(!list_empty(&ctx->killed_trees));
@@ -1093,8 +1093,9 @@ static inline void audit_free_context(struct audit_context *context)
 }
 
 static int audit_log_pid_context(struct audit_context *context, pid_t pid,
-				 kuid_t auid, kuid_t uid, unsigned int sessionid,
-				 u32 sid, char *comm)
+				 kuid_t auid, kuid_t uid,
+				 unsigned int sessionid, struct lsm_prop *prop,
+				 char *comm)
 {
 	struct audit_buffer *ab;
 	char *ctx = NULL;
@@ -1108,8 +1109,8 @@ static int audit_log_pid_context(struct audit_context *context, pid_t pid,
 	audit_log_format(ab, "opid=%d oauid=%d ouid=%d oses=%d", pid,
 			 from_kuid(&init_user_ns, auid),
 			 from_kuid(&init_user_ns, uid), sessionid);
-	if (sid) {
-		if (security_secid_to_secctx(sid, &ctx, &len)) {
+	if (lsmprop_is_set(prop)) {
+		if (security_lsmprop_to_secctx(prop, &ctx, &len)) {
 			audit_log_format(ab, " obj=(none)");
 			rc = 1;
 		} else {
@@ -1778,7 +1779,7 @@ static void audit_log_exit(void)
 						  axs->target_auid[i],
 						  axs->target_uid[i],
 						  axs->target_sessionid[i],
-						  axs->target_sid[i],
+						  &axs->target_ref[i],
 						  axs->target_comm[i]))
 				call_panic = 1;
 	}
@@ -1787,7 +1788,7 @@ static void audit_log_exit(void)
 	    audit_log_pid_context(context, context->target_pid,
 				  context->target_auid, context->target_uid,
 				  context->target_sessionid,
-				  context->target_sid, context->target_comm))
+				  &context->target_ref, context->target_comm))
 			call_panic = 1;
 
 	if (context->pwd.dentry && context->pwd.mnt) {
@@ -2722,15 +2723,12 @@ int __audit_sockaddr(int len, void *a)
 void __audit_ptrace(struct task_struct *t)
 {
 	struct audit_context *context = audit_context();
-	struct lsm_prop prop;
 
 	context->target_pid = task_tgid_nr(t);
 	context->target_auid = audit_get_loginuid(t);
 	context->target_uid = task_uid(t);
 	context->target_sessionid = audit_get_sessionid(t);
-	security_task_getlsmprop_obj(t, &prop);
-	/* scaffolding */
-	context->target_sid = prop.scaffold.secid;
+	security_task_getlsmprop_obj(t, &context->target_ref);
 	memcpy(context->target_comm, t->comm, TASK_COMM_LEN);
 }
 
@@ -2746,7 +2744,6 @@ int audit_signal_info_syscall(struct task_struct *t)
 	struct audit_aux_data_pids *axp;
 	struct audit_context *ctx = audit_context();
 	kuid_t t_uid = task_uid(t);
-	struct lsm_prop prop;
 
 	if (!audit_signals || audit_dummy_context())
 		return 0;
@@ -2758,9 +2755,7 @@ int audit_signal_info_syscall(struct task_struct *t)
 		ctx->target_auid = audit_get_loginuid(t);
 		ctx->target_uid = t_uid;
 		ctx->target_sessionid = audit_get_sessionid(t);
-		security_task_getlsmprop_obj(t, &prop);
-		/* scaffolding */
-		ctx->target_sid = prop.scaffold.secid;
+		security_task_getlsmprop_obj(t, &ctx->target_ref);
 		memcpy(ctx->target_comm, t->comm, TASK_COMM_LEN);
 		return 0;
 	}
@@ -2781,9 +2776,7 @@ int audit_signal_info_syscall(struct task_struct *t)
 	axp->target_auid[axp->pid_count] = audit_get_loginuid(t);
 	axp->target_uid[axp->pid_count] = t_uid;
 	axp->target_sessionid[axp->pid_count] = audit_get_sessionid(t);
-	security_task_getlsmprop_obj(t, &prop);
-	/* scaffolding */
-	axp->target_sid[axp->pid_count] = prop.scaffold.secid;
+	security_task_getlsmprop_obj(t, &axp->target_ref[axp->pid_count]);
 	memcpy(axp->target_comm[axp->pid_count], t->comm, TASK_COMM_LEN);
 	axp->pid_count++;