Target partition filesystem already mounted

[Diomeh]

Describe the bug

Executing WoeUSB fails to flash ISO image with the message

mkdosfs: /dev/sda1 contains a mounted filesystem.
ERROR: The command ""${command_mkdosfs}" -F 32 -n "${filesystem_label}" "${target_partition}"" failed with exit status "1", program is prematurely aborted

To Reproduce

Steps to reproduce the behavior:

Execute WoeUSB normally

sudo ./woeusb-5.2.4.bash --device Win10_21H2_Spanish_x64.iso /dev/sda

In my case, I'm using a Windows 10 ISO image downloaded directly from Microsoft and the target partition is located at /dev/sda

Expected behavior

WoeUSB should flash the ISO image to the target partition

Teminal output

WoeUSB v5.2.4
==============================
Info: Mounting source filesystem...
Info: Wiping all existing partition table and filesystem signatures in /dev/sda...
/dev/sda: 2 bytes were erased at offset 0x000001fe (dos): 55 aa
/dev/sda: calling ioctl to re-read partition table: Success
Info: Ensure that /dev/sda is really wiped...
Info: Creating new partition table on /dev/sda...
Info: Creating target partition...
Info: Making system realize that partition table has changed...
Info: Wait 3 seconds for block device nodes to populate...
mkfs.fat 4.2 (2021-01-31)
mkdosfs: /dev/sda1 contains a mounted filesystem.
ERROR: The command ""${command_mkdosfs}" -F 32 -n "${filesystem_label}" "${target_partition}"" failed with exit status "1", program is prematurely aborted
Info: Unmounting and removing "/tmp/woeusb-source-20220921-094402-Wednesday.AP7vAI"...
Warning: Target device is busy, please make sure you unmount all filesystems on target device or shutdown the computer before detaching it.

Environment

• OS: Ubuntu 22.04.1 LTS
• Bash: GNU bash, version 5.1.16(1)-release (x86_64-pc-linux-gnu)
• WoeUSB: 5.2.4

[Diomeh]

So, after digging through the bash script a bit I found the failing call at line 1304.

# Format target partition's filesystem
case "${filesystem_type}" in
    FS_FAT)
        #########################
        # This call will fail if target partition is already mounted
        #########################
        "${command_mkdosfs}" \
            -F 32 \
            -n "${filesystem_label}" \
            "${target_partition}"
        ;;

I managed to work around this problem by making sure that the target partition is unmounted before the call

# Format target partition's filesystem
case "${filesystem_type}" in
    FS_FAT)
        #########################
        # unmount target partition
        #########################
        umount \
            "${target_partition}" \
            || true

        "${command_mkdosfs}" \
            -F 32 \
            -n "${filesystem_label}" \
            "${target_partition}"
        ;;

[floscher]

@Diomeh This was probably caused by new partitions being auto-mounted as soon as they are detected (as described in #101).

A workaround would be to temporarily (until reboot) stop this service:

systemctl stop udisks2.service