diff --git a/sys/kern/posix4_mib.c b/sys/kern/posix4_mib.c
index a2be3ff9ebf..d2a8582424f 100644
--- a/sys/kern/posix4_mib.c
+++ b/sys/kern/posix4_mib.c
@@ -113,9 +113,9 @@ p31b_sysctl_proc(SYSCTL_HANDLER_ARGS)
 	num = arg2;
 	if (!P31B_VALID(num))
 		return (EINVAL);
-	val = facility_initialized[num] ? facility[num - 1] : 0;
+	val = facility_initialized[num - 1] ? facility[num - 1] : 0;
 	error = sysctl_handle_int(oidp, &val, 0, req);
-	if (error == 0 && req->newptr != NULL && facility_initialized[num])
+	if (error == 0 && req->newptr != NULL && facility_initialized[num - 1])
 		facility[num - 1] = val;
 	return (error);
 }
@@ -137,7 +137,7 @@ p31b_unsetcfg(int num)
 {
 
 	facility[num - 1] = 0;
-	facility_initialized[num -1] = 0;
+	facility_initialized[num - 1] = 0;
 }
 
 int