Tracking: Permission Errors when restoring and creating cache

Issue

Files not created by the local user may fail when restored from the cache as tar preserves file permissions. Permission errors can also occur when the current user does not have permissions to read files when creating the cache. This is likely just a Linux and/or macOS issue (all the reports are Linux)

Reports

• https://github.com/actions/cache/issues/11
• https://github.com/actions/cache/issues/117
• https://github.com/actions/cache/issues/130
• https://github.com/actions/cache/issues/131

Possible solutions

1. Run tar with sudo
   • What are the downsides of this approach?

[bjorn3]

lrwxrwxrwx 1 runner docker 22 Mar 13 15:33 /home/runner/.cargo -> /usr/share/rust/.cargo

~/.cargo is a symlink for /usr/share/rust/.cargo, so the chown only changed the owner of the symlink. Appending a / to the path (sudo chown -R $(whoami):$(id -ng) ~/.cargo/) does fix it without requiring a cache invalidation.

[bjorn3]

I worked around this using sudo chown -R $(whoami):$(id -ng) ~/.cargo to make ~/.cargo owned by the current user.