merge branch 'pr-2317'
merge branch 'pr-2317'

Ted Yu (1):
  Defer netns.Close() after error check

LGTMs: ae36a26daa30f0031f01ac5f49d21409217e1dee@cyphar
Closes #2317

estesp/runc,opencontainers/runc,estesp/runc,mikebrow/runc,opencontainers/runc,xiaochenshen/runc,dqminh/runc,rhatdan/runc,mikebrow/runc,rhatdan/runc,estesp/runc,kolyshkin/runc,dqminh/runc,kolyshkin/runc,opencontainers/runc,opencontainers/runc,kolyshkin/runc,dqminh/runc,rhatdan/runc,dqminh/runc,rhatdan/runc,mikebrow/runc,xiaochenshen/runc,xiaochenshen/runc,kolyshkin/runc