[CLOUDSTACK-10356] Fix Some Potential NPE

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 4.12.0.0
• Fix Version/s: 4.12
• Security Level: Public (Anyone can view this level - this is the default.)
• Assignee: Unassigned
• Reporter: lujie
• Created: 15/Apr/18 05:48
• Updated: 26/Apr/18 13:04
• Resolved: 26/Apr/18 13:04

Description

We have developed a static analysis tool NPEDetector to find some potential NPE. Our analysis shows that some callees may return null in corner case(e.g. node crash , IO exception), some of their callers have  !=null check but some do not have. In this issue we post a patch which can add  !=null  based on existed !=null  check. For example:

Callee GlobalLoadBalancingRulesServiceImpl#lookupGslbServiceProvider:

protected GslbServiceProvider lookupGslbServiceProvider() {
    return _gslbProviders.size() == 0 ? null : _gslbProviders.get(0);// may return null;
}

Caller GlobalLoadBalancingRulesServiceImpl#checkGslbServiceEnabledInZone have !=null:

private boolean checkGslbServiceEnabledInZone(long zoneId, long physicalNetworkId) {

   GslbServiceProvider gslbProvider = lookupGslbServiceProvider();
   if (gslbProvider == null) {
      throw new CloudRuntimeException("No GSLB provider is available");
   }

   return gslbProvider.isServiceEnabledInZone(zoneId, physicalNetworkId);
}

but another GlobalLoadBalancingRulesServiceImpl#applyGlobalLoadBalancerRuleConfig does not have !=null check:

GslbServiceProvider gslbProvider = lookupGslbServiceProvider();
siteLb.setGslbProviderPublicIp(gslbProvider.getZoneGslbProviderPublicIp(dataCenterId,physicalNetworkId));
.........

So we will add below code in non-(!=null) caller GlobalLoadBalancingRulesServiceImpl#applyGlobalLoadBalancerRuleConfig

if (gslbProvider == null) {
    throw new CloudRuntimeException("No GSLB provider is available");
}

But due to we are not very  familiar with CLOUDSTACK, hope some expert can review it.

Thanks!!!!

Issue Links

• links to: GitHub Pull Request #2573