[TS-3294] Add null pointer check
[TS-3294] Add null pointer check

Coverity CID:1021867

davidbz/trafficserver,taoyunxing/trafficserver,persiaAziz/trafficserver,chitianhao/trafficserver,reveller/trafficserver,PSUdaemon/trafficserver,bryancall/trafficserver,dyrock/trafficserver,vmamidi/trafficserver,pbchou/trafficserver,duke8253/trafficserver,SolidWallOfCode/trafficserver,pbchou/trafficserver,vmamidi/trafficserver,persiaAziz/trafficserver,taoyunxing/trafficserver,rpufky/trafficserver,taoyunxing/trafficserver,reveller/trafficserver,clearswift/trafficserver,bryancall/trafficserver,chenglongwei/trafficserver,rpufky/trafficserver,chitianhao/trafficserver,vmamidi/trafficserver,PSUdaemon/trafficserver,taoyunxing/trafficserver,rpufky/trafficserver,rpufky/trafficserver,bryancall/trafficserver,dyrock/trafficserver,chenglongwei/trafficserver,SolidWallOfCode/trafficserver,PSUdaemon/trafficserver,duke8253/trafficserver,dyrock/trafficserver,reveller/trafficserver,dyrock/trafficserver,duke8253/trafficserver,PSUdaemon/trafficserver,clearswift/trafficserver,clearswift/trafficserver,reveller/trafficserver,davidbz/trafficserver,persiaAziz/trafficserver,rahmalik/trafficserver,PSUdaemon/trafficserver,pbchou/trafficserver,chenglongwei/trafficserver,persiaAziz/trafficserver,davidbz/trafficserver,SolidWallOfCode/trafficserver,dyrock/trafficserver,davidbz/trafficserver,duke8253/trafficserver,taoyunxing/trafficserver,taoyunxing/trafficserver,reveller/trafficserver,pbchou/trafficserver,davidbz/trafficserver,clearswift/trafficserver,chenglongwei/trafficserver,chitianhao/trafficserver,rahmalik/trafficserver,chitianhao/trafficserver,rpufky/trafficserver,taoyunxing/trafficserver,taoyunxing/trafficserver,duke8253/trafficserver,chitianhao/trafficserver,clearswift/trafficserver,duke8253/trafficserver,reveller/trafficserver,persiaAziz/trafficserver,pbchou/trafficserver,rahmalik/trafficserver,rahmalik/trafficserver,persiaAziz/trafficserver,persiaAziz/trafficserver,rahmalik/trafficserver,rahmalik/trafficserver,SolidWallOfCode/trafficserver,chenglongwei/trafficserver,vmamidi/trafficserver,PSUdaemon/trafficserver,dyrock/trafficserver,vmamidi/trafficserver,clearswift/trafficserver,chenglongwei/trafficserver,rpufky/trafficserver,dyrock/trafficserver,pbchou/trafficserver,chitianhao/trafficserver,rahmalik/trafficserver,clearswift/trafficserver,chenglongwei/trafficserver,reveller/trafficserver,rahmalik/trafficserver,clearswift/trafficserver,PSUdaemon/trafficserver,duke8253/trafficserver,rpufky/trafficserver,bryancall/trafficserver,bryancall/trafficserver,taoyunxing/trafficserver,rpufky/trafficserver,SolidWallOfCode/trafficserver,persiaAziz/trafficserver,SolidWallOfCode/trafficserver,reveller/trafficserver,rpufky/trafficserver,davidbz/trafficserver,rahmalik/trafficserver,chitianhao/trafficserver,vmamidi/trafficserver,chenglongwei/trafficserver,clearswift/trafficserver,reveller/trafficserver,PSUdaemon/trafficserver,bryancall/trafficserver,PSUdaemon/trafficserver,SolidWallOfCode/trafficserver