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SELinux is a labeling system. Sometimes the labels on disk can get messed up. One way to fix this is to trigger a full relabel on the next boot.
You can toggle this behavior using this screen.
Note: Sometimes a simple restorecon is all you need to fix the labels on a file or directory.
If you add a new disk which does not have labels you could simply execute
# restorecon -R -v PATHTODISK