Podman doesn't check existance of given --authfile

[sshnaidm]

Is this a BUG REPORT or FEATURE REQUEST? (leave only one on its own line)

/kind bug

Description

Steps to reproduce the issue:

1. podman run --auth=/tmp/nonexist --rm alpine sh

Describe the results you received:
Podman starts container as usual

Describe the results you expected:
Podman should fail because /tmp/nonexist doesn't exist

Additional information you deem important (e.g. issue happens only occasionally):

Output of podman version:

podman version 1.6.1

Output of podman info --debug:

  debug:
  compiler: gc
  git commit: ""
  go version: go1.12.9
  podman version: 1.6.1
host:
  BuildahVersion: 1.11.2
  CgroupVersion: v1
  Conmon:
    package: conmon-2.0.1-1.fc30.x86_64
    path: /usr/bin/conmon
    version: 'conmon version 2.0.1, commit: 4346fbe0b2634b05857973bdf663598081240374'
  Distribution:
    distribution: fedora
    version: "30"
  MemFree: 1473187840
  MemTotal: 25091493888
  OCIRuntime:
    package: runc-1.0.0-95.rc9.gitc1485a1.fc30.x86_64
    path: /usr/bin/runc
    version: |-
      runc version 1.0.0-rc9+dev
      commit: 0840802d505e28d3adcbc7a275cbeadbdf64ddec
      spec: 1.0.1-dev
  SwapFree: 11110969344
  SwapTotal: 12645822464
  arch: amd64
  cpus: 4
  eventlogger: journald
  hostname: sshnaidm.remote
  kernel: 5.3.6-200.fc30.x86_64
  os: linux
  rootless: true
  slirp4netns:
    Executable: /usr/bin/slirp4netns
    Package: slirp4netns-0.4.0-4.git19d199a.fc30.x86_64
    Version: |-
      slirp4netns version 0.4.0-beta.2
      commit: 19d199a6ca424fcf9516320a327cedad85cf4dfb
  uptime: 32h 36m 28.81s (Approximately 1.33 days)
registries:
  blocked: null
  insecure: null
  search:
  - docker.io
  - registry.fedoraproject.org
  - quay.io
  - registry.access.redhat.com
  - registry.centos.org
store:
  ConfigFile: /home/sshnaidm/.config/containers/storage.conf
  ContainerStore:
    number: 4
  GraphDriverName: overlay
  GraphOptions:
    overlay.mount_program:
      Executable: /usr/bin/fuse-overlayfs
      Package: fuse-overlayfs-0.6.4-2.fc30.x86_64
      Version: |-
        fusermount3 version: 3.6.2
        fuse-overlayfs: version 0.6.4
        FUSE library version 3.6.2
        using FUSE kernel interface version 7.29
  GraphRoot: /home/sshnaidm/.local/share/containers/storage
  GraphStatus:
    Backing Filesystem: extfs
    Native Overlay Diff: "false"
    Supports d_type: "true"
    Using metacopy: "false"
  ImageStore:
    number: 21
  RunRoot: /tmp/1000
  VolumePath: /home/sshnaidm/.local/share/containers/storage/volumes

Package info (e.g. output of rpm -q podman or apt list podman):

podman-1.6.1-2.fc30.x86_64

[rhatdan]

@QiWang19 PTAL
We want this fixed soon