On Wed, Feb 12, 2020 at 08:16:04AM -0800, Darrick J. Wong wrote: > xfs_setattr_nonsize calls posix_acl_chmod which returns EOPNOTSUPP > because the xfs symlink inode_operations do not include a ->set_acl > pointer. > > I /think/ that posix_acl_chmod code exists to enforce that the file mode > reflects any acl that might be set on the inode, but in this case the > inode is a symbolic link. > > I don't remember off the top of my head if ACLs are supposed to apply to > symlinks, but what do you think about adding get_acl/set_acl pointers to > xfs_symlink_inode_operations and xfs_inline_symlink_inode_operations ? Symlinks don't have permissions or ACLs, so adding them makes no sense. xfs doesn't seem all that different from the other file systems, so I suspect you'll also see it with other on-disk file systems. We probably need a check high up in the chmod and co code to reject the operation early for O_PATH file descriptors pointing to symlinks.
