Description of problem:
On trying to import RHGSC appliance-3.2, the dialog showing "Failed to load VM configuration OVA file: /root/rhgsc-appliance-3.2-rhel-6-x86_64.rhevm.ova

The correct issue is mentioned in vdsm.log

Version-Release number of selected component (if applicable):
ovirt-engine-4.1.6

How reproducible:
100%

Steps to Reproduce:
1. Copy file to Hypervisor 
2. import the appropriate file via "Import Virtual Machines" Dialog.


Actual results:
"Failed to load VM configuration OVA file: /root/rhgsc-appliance-3.2-rhel-6-x86_64.rhevm.ova

Expected results:
The import should work correctly

Additional info:
This issue does have different flavors.

1. IOError: [Errno 13] Permission denied: u'/root/rhgsc-appliance-3.2-rhel-6-x86_64.rhevm.ova'


2018-03-23 12:03:45,109+0100 INFO  (jsonrpc/2) [jsonrpc.JsonRpcServer] RPC call Host.getHardwareInfo succeeded in 0.00 seconds (__init__:539)
2018-03-23 12:03:45,111+0100 INFO  (jsonrpc/4) [jsonrpc.JsonRpcServer] RPC call VM.getStats failed (error 1) in 0.00 seconds (__init__:539)
2018-03-23 12:03:48,563+0100 ERROR (jsonrpc/6) [jsonrpc.JsonRpcServer] Internal server error (__init__:577)
Traceback (most recent call last):
  File "/usr/lib/python2.7/site-packages/yajsonrpc/__init__.py", line 572, in _handle_request
    res = method(**params)
  File "/usr/lib/python2.7/site-packages/vdsm/rpc/Bridge.py", line 202, in _dynamicMethod
    result = fn(*methodArgs)
  File "/usr/share/vdsm/API.py", line 1537, in getExternalVmFromOva
    return v2v.get_ova_info(ova_path)
  File "/usr/lib/python2.7/site-packages/vdsm/v2v.py", line 226, in get_ova_info
    root = ET.fromstring(_read_ovf_from_ova(ova_path))
  File "/usr/lib/python2.7/site-packages/vdsm/v2v.py", line 1207, in _read_ovf_from_ova
    elif tarfile.is_tarfile(ova_path):
  File "/usr/lib64/python2.7/tarfile.py", line 2585, in is_tarfile
    t = open(name)
  File "/usr/lib64/python2.7/tarfile.py", line 1660, in open
    return func(name, "r", fileobj, **kwargs)
  File "/usr/lib64/python2.7/tarfile.py", line 1722, in gzopen
    fileobj = bltn_open(name, mode + "b")
IOError: [Errno 13] Permission denied: u'/root/rhgsc-appliance-3.2-rhel-6-x86_64.rhevm.ova'
2018-03-23 12:03:48,564+0100 INFO  (jsonrpc/6) [jsonrpc.JsonRpcServer] RPC call Host.getExternalVmFromOva failed (error -32603) in 0.01 seconds (__init__:539)
2018-03-23 12:03:49,398+0100 INFO  (jsonrpc/3) [jsonrpc.JsonRpcServer] RPC call Host.getAllVmStats succeeded in 0.01 seconds (__init__:539)
2018-03-23 12:03:49,712+0100 INFO  (Reactor thread) [ProtocolDetector.AcceptorImpl] Accepted connection from ::1:44296 (protocoldetector:72)
2018-03-23 12:03:49,716+0100 INFO  (Reactor thread) [ProtocolDetector.Detector] Detected protocol stomp from ::1:44296 (protocoldetector:127)



2. V2VError: Error parsing ovf information: no memory size

2018-03-23 12:12:07,611+0100 INFO  (jsonrpc/4) [jsonrpc.JsonRpcServer] RPC call Host.getHardwareInfo succeeded in 0.00 seconds (__init__:539)
2018-03-23 12:12:07,839+0100 ERROR (jsonrpc/7) [jsonrpc.JsonRpcServer] Internal server error (__init__:577)
Traceback (most recent call last):
  File "/usr/lib/python2.7/site-packages/yajsonrpc/__init__.py", line 572, in _handle_request
    res = method(**params)
  File "/usr/lib/python2.7/site-packages/vdsm/rpc/Bridge.py", line 202, in _dynamicMethod
    result = fn(*methodArgs)
  File "/usr/share/vdsm/API.py", line 1537, in getExternalVmFromOva
    return v2v.get_ova_info(ova_path)
  File "/usr/lib/python2.7/site-packages/vdsm/v2v.py", line 231, in get_ova_info
    _add_general_ovf_info(vm, root, ns, ova_path)
  File "/usr/lib/python2.7/site-packages/vdsm/v2v.py", line 1260, in _add_general_ovf_info
    raise V2VError('Error parsing ovf information: no memory size')
V2VError: Error parsing ovf information: no memory size
2018-03-23 12:12:07,840+0100 INFO  (jsonrpc/7) [jsonrpc.JsonRpcServer] RPC call Host.getExternalVmFromOva failed (error -32603) in 0.00 seconds (__init__:539)
2018-03-23 12:12:08,054+0100 INFO  (jsonrpc/0) [jsonrpc.JsonRpcServer] RPC call Host.getAllVmStats succeeded in 0.02 seconds (__init__:539)