tree 377086556cf88b99ffba8b935c6a72d1f365ba9c
parent 754f8cb72b42a3a6100d2bbb1cb885361a7310dd
author Miklos Szeredi <mszeredi@redhat.com> 1469786723 +0200
committer Miklos Szeredi <mszeredi@redhat.com> 1469786723 +0200

ovl: simplify permission checking

The fact that we always do permission checking on the overlay inode and
clear MAY_WRITE for checking access to the lower inode allows cruft to be
removed from ovl_permission().

1) "default_permissions" option effectively did generic_permission() on the
overlay inode with i_mode, i_uid and i_gid updated from underlying
filesystem.  This is what we do by default now.  It did the update using
vfs_getattr() but that's only needed if the underlying filesystem can
change (which is not allowed).  We may later introduce a "paranoia_mode"
that verifies that mode/uid/gid are not changed.

2) splitting out the IS_RDONLY() check from inode_permission() also becomes
unnecessary once we remove the MAY_WRITE from the lower inode check.

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>