mount module does not add mountpoint correctly if /etc/fstab does not end with a newline

[saito-hideki]

SUMMARY

mount module does not add mountpoint correctly if /etc/fstab does not end with a newline.

ISSUE TYPE

• Bug Report

COMPONENT NAME

• ansible.posix.mount

ANSIBLE VERSION

2.12.0.dev0

CONFIGURATION

[1] ansible.cfg

$ ansible-config dump --only-changed
CALLBACKS_ENABLED(/home/hsaito/work/testing/collections/ansible.cfg) = ['ansible.posix.profile_tasks']
COLLECTIONS_PATHS(/home/hsaito/work/testing/collections/ansible.cfg) = ['/home/hsaito/work/testing/collections']
DISPLAY_SKIPPED_HOSTS(/home/hsaito/work/testing/collections/ansible.cfg) = False
HOST_KEY_CHECKING(/home/hsaito/work/testing/collections/ansible.cfg) = False

[2] Playbook

---
- hosts: linux
  gather_facts: false

  tasks:
    - ansible.posix.mount:
        src: /dev/vdb1
        path: /mnt
        opts: defaults
        state: mounted
        fstype: xfs
        state: mounted
      become: true

[3] There is no newline at the end of file of /etc/fstab:

[root@server00 ~]# cat /etc/fstab 
... snip ...
/dev/mapper/cl-root     /                       xfs     defaults        0 0
UUID=fd99bb22-3376-434f-b976-f0e0845ddf1b /boot                   ext4    defaults        1 2
/dev/mapper/cl-swap     swap                    swap    defaults        0 0

# No newline at EOF[root@server00 ~]# 

[root@server00 ~]# od -xc /etc/fstab 
... snip ...
0001100    3020    0a0a    2023    6f4e    6e20    7765    696c    656e
              0  \n  \n   #       N   o       n   e   w   l   i   n   e
0001120    6120    2074    4f45    0046
              a   t       E   O   F
0001127

OS / ENVIRONMENT

• Control Node: Fedora34
• Managed Node: CentOS Stream release 8

STEPS TO REPRODUCE

Launch playbook [2] to manage /etc/fstab [3]

$ ansible-playbook -i inventory playbook/mount/mount_linux_xfs.yml 

PLAY [linux] *********************************************************************************************************
Tuesday 15 June 2021  22:03:54 +0900 (0:00:00.028)       0:00:00.028 ********** 

TASK [ansible.posix.mount] *******************************************************************************************
changed: [server00]

PLAY RECAP ***********************************************************************************************************
server00                   : ok=1    changed=1    unreachable=0    failed=0    skipped=0    rescued=0    ignored=0   

Tuesday 15 June 2021  22:03:55 +0900 (0:00:00.535)       0:00:00.564 ********** 
=============================================================================== 
ansible.posix.mount ------------------------------------------------------------------------------------------- 0.54s

EXPECTED RESULTS

mount succeeded and new mountpoint added to /etc/fstab correctly:

[root@server00 ~]# mount
... snip ...
/dev/vdb1 on /mnt type xfs (rw,relatime,attr2,inode64,noquota)

[root@server00 ~]# cat /etc/fstab 
... snip ...
# No newline at EOF
/dev/vdb1 /mnt xfs defaults 0 0

ACTUAL RESULTS

mount succeeded, but incorrect mountpoint was added to /etc/fstab:

... snip ...
# No newline at EOF/dev/vdb1 /mnt xfs defaults 0 0