I have two writeable directories branch1 and branch2 tied together with AUFS on Debian 8 to the mount point union.Mount options: br=branch1=rw:branch2=rwbranch1 and branch2 each contain a subdirectory dir with permissions 700. When I change the permissions with chmod 755 union/dir, only the first directory branch1/dir is altered, branch2/dir ramains as it is.Problem: Group and other users can't access union/dir even after setting chmod 755 because branch2/dir is still chmod 700.Is there a way to make AUFS apply changed permissions to all directories in the union or is it always limited to the topmost one?
AUFS only changes permissions of the topmost directory
permissions;directory;aufs
It sounds to me like you have done everything right, so I would suggest filing a bug against aufs.PS: Kontrollfreak has done that already, and the fix is to use the dirperm1 mount option, according to http://sourceforge.net/p/aufs/bugs/21/#1293 .  Thanks for your research @Kontrollfreak .