diff --git a/CHANGES b/CHANGES
index 55fb5fcf45..05ba201d90 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,7 @@
+6196.	[cleanup]	Report "permission denied" instead of "unexpected error"
+			when trying to update a zone file on a read-only file
+			system. Thanks to Midnight Veil. [GL #4134]
+
 6195.	[bug]		Use rcu to reference view->adb. [GL #4021]
 
 6194.	[func]		Change function 'find_zone_keys()' to look for signing
diff --git a/lib/isc/errno2result.c b/lib/isc/errno2result.c
index a6646d2181..1ef0c884d5 100644
--- a/lib/isc/errno2result.c
+++ b/lib/isc/errno2result.c
@@ -45,6 +45,7 @@ isc___errno2result(int posixerrno, bool dolog, const char *file,
 		return (ISC_R_FILENOTFOUND);
 	case EACCES:
 	case EPERM:
+	case EROFS:
 		return (ISC_R_NOPERM);
 	case EEXIST:
 		return (ISC_R_FILEEXISTS);