diff --git a/PVE/API2/Qemu.pm b/PVE/API2/Qemu.pm
index 70bdd296..9402ad38 100644
--- a/PVE/API2/Qemu.pm
+++ b/PVE/API2/Qemu.pm
@@ -111,7 +111,7 @@ my $create_disks = sub {
 my $check_vm_modify_config_perm = sub {
     my ($rpcenv, $authuser, $vmid, $pool, $key_list) = @_;
 
-    return 1 if $authuser ne 'root@pam';
+    return 1 if $authuser eq 'root@pam';
 
     foreach my $opt (@$key_list) {
 	# disk checks need to be done somewhere else