fix coverity detected defects
fix coverity detected defects

cvmfs/cvmfs,Moliholy/cvmfs,cvmfs-testing/cvmfs,reneme/cvmfs,reneme/cvmfs,alhowaidi/cvmfsNDN,cvmfs/cvmfs,MicBrain/cvmfs,cvmfs/cvmfs,trshaffer/cvmfs,djw8605/cvmfs,djw8605/cvmfs,reneme/cvmfs,cvmfs-testing/cvmfs,Gangbiao/cvmfs,djw8605/cvmfs,MicBrain/cvmfs,Gangbiao/cvmfs,cvmfs-testing/cvmfs,cvmfs/cvmfs,Moliholy/cvmfs,Gangbiao/cvmfs,cvmfs/cvmfs,cvmfs/cvmfs,Moliholy/cvmfs,DrDaveD/cvmfs,DrDaveD/cvmfs,reneme/cvmfs,Gangbiao/cvmfs,DrDaveD/cvmfs,alhowaidi/cvmfsNDN,Moliholy/cvmfs,cvmfs/cvmfs,trshaffer/cvmfs,Gangbiao/cvmfs,cvmfs-testing/cvmfs,alhowaidi/cvmfsNDN,DrDaveD/cvmfs,alhowaidi/cvmfsNDN,DrDaveD/cvmfs,Moliholy/cvmfs,djw8605/cvmfs,trshaffer/cvmfs,djw8605/cvmfs,trshaffer/cvmfs,cvmfs-testing/cvmfs,DrDaveD/cvmfs,reneme/cvmfs,trshaffer/cvmfs,MicBrain/cvmfs,DrDaveD/cvmfs,alhowaidi/cvmfsNDN,MicBrain/cvmfs,MicBrain/cvmfs