opatchauto : ContentsXML/oui-patch.xml (Permission denied)

SYMPTOMS

When applying 19c GI JULY 2020 RU ( 19.8.0.0), opatchauto failed with following errors:

[root@racnode2 ~]# opatchauto apply /tmp/31305339/
...
..
.

Reason: Failed during Patching: oracle.opatch.opatchsdk.OPatchException: ApplySession failed in system modification phase… 'ApplySession::apply failed: java.io.IOException: oracle.sysman.oui.patch.PatchException: java.io.FileNotFoundException: /u01/app/oraInventory/ContentsXML/oui-patch.xml (Permission denied)'

After fixing the cause of failure Run opatchauto resume

]
OPATCHAUTO-68061: The orchestration engine failed.
OPATCHAUTO-68061: The orchestration engine failed with return code 1
OPATCHAUTO-68061: Check the log for more details.
OPatchAuto failed.