meta-nilrt: udev-extraconf: update worldwritable permissions

[Nasrulla-NI]

Summary of Changes

Currently NILRT will automatically mount block and TTY devices as world-writable and should be updated to no longer do this.
We should try to avoid just changing the permissions and should instead have some way to toggle the world-writable permissions back on if needed. Hence to do this - /etc/natinst/share/ni-rt.ini - worldwritable.enabled="true" or worldwritable.enabled="false" is appended as per information provided from hardware config team/

• Controls whether VFAT/TTY mounts are world-writable.
• 0 = default restrictive (fmask=0002,dmask=0002)
• 1 = world-writable (fmask=0000,dmask=0000)
• Reads /** /etc/natinst/share/ni-rt.ini - worldwritable.enabled="true" or worldwritable.enabled="false" **

Justification

Please refer below feature
https://dev.azure.com/ni/DevCentral/_workitems/edit/3470239

Testing

Safemode:
VFAT and TTY:
- worldwritable.enabled="false"

worldwritable.enabled="true"

Runmode:
VFAT and TTY:
- worldwritable.enabled="false"

worldwritable.enabled="true"

• I have built the core package feed with this PR in place. (bitbake packagefeed-ni-core)

Procedure

• I certify that the contents of this pull request complies with the Developer Certificate of Origin.

[amstewart]

We should try to avoid just changing the permissions and should instead have some way to toggle the world-writable permissions back on if needed.

Why? Because of VISA? VISA has to run as a user that isn't root or a member of the dialout group?

[Nasrulla-NI]

We should try to avoid just changing the permissions and should instead have some way to toggle the world-writable permissions back on if needed.

Why? Because of VISA? VISA has to run as a user that isn't root or a member of the dialout group?

Thanks for the comment. Indeed, the change was aimed at supporting VISA, since it often runs as a non‑root user without dialout membership and needs access to these device nodes. So, added a config/feature flag so the relaxed permissions are enabled only when needed. This will be controlled from front end Hwconfig.

[rajendra-desai-ni]

Commit message changes:

• Change commit title to be more specific, something like:
  udev-extraconf: update worldwritable permissions
• Update commit message to have more info about the changes
• Signed-off tag should be at the end

[Copilot]

Pull request overview

This PR introduces a runtime-configurable toggle (worldwritable.enabled from /etc/natinst/share/ni-rt.ini via nirtcfg) to control whether VFAT mounts and USB serial TTY devices are world-writable, defaulting to a more restrictive mode.

Changes:

• Add a udev IMPORT helper script that exposes a NI_WORLDWRITABLE environment variable derived from worldwritable.enabled.
• Update VFAT automount options to be restrictive by default (fmask=0002,dmask=0002) with an opt-in to world-writable.
• Update USB serial udev rules to set MODE based on NI_WORLDWRITABLE.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 7 comments.

File	Description
recipes-core/udev/udev-extraconf/scripts/ni-worldwritable.sh	New udev IMPORT helper that maps worldwritable.enabled to NI_WORLDWRITABLE=0/1.
recipes-core/udev/udev-extraconf/scripts/mount.sh	Makes VFAT mount permissions configurable at runtime instead of always world-writable.
recipes-core/udev/udev-extraconf/rules.d/usb-serial-permissions.rules	Makes ttyUSB*/ttyACM* device mode configurable at runtime via udev IMPORT.

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[chaitu236]

Other than copilot suggestions, looks good. I don't have any other feedback.