MPM silently fails when /tmp directory lacks execute permission

[bryanjia222]

Problem Description

MATLAB Package Manager (MPM) silently fails when the /tmp directory lacks execute permission, exiting without any error messages or output, making it extremely difficult for users to diagnose the issue.

Environment Information

• Operating System: Linux (Ubuntu 24.04)
• Architecture: x86_64

Steps to Reproduce

1. Download and setup MPM:

   wget https://www.mathworks.com/mpm/glnxa64/mpm
   chmod +x mpm

2. Set /tmp directory to noexec:

   sudo mount -o remount,noexec /tmp

3. Run any MPM command:

   ./mpm --version
   ./mpm install --release=R2025a --destination=~/matlab --products=MATLAB

Actual Behavior

• MPM command executes and immediately returns to command prompt
• No output, error messages, or logs are displayed
• Program fails silently with no indication of the failure reason

Expected Behavior

MPM should:

1. Detect the execute permission status of the /tmp directory
2. If /tmp directory lacks execute permission, display a clear error message such as:

   Error: MPM requires execute permission on temporary directory /tmp
   Please ensure /tmp has exec permission or set TMPDIR to a directory with exec permission
   

3. Provide solution suggestions

Diagnostic Information

Analysis using strace revealed:

• Program attempts to create and execute temporary files in /tmp/mwse_* directories
• Due to lack of exec permission on /tmp, the program exits abnormally
• Exit status is not the normal exit_group(0)

Current Workaround

The current workaround is:

# Temporary fix
sudo mount -o remount,exec /tmp

# Or set a different temporary directory
export TMPDIR=/path/to/writable/executable/dir

[mw-wtripp]

Thanks, @bryanjia222, for bringing this to our attention. We are currently investigating this issue and will keep you posted on our progress.