• Eric W. Biederman's avatar
    userns: Remove implicit MNT_NODEV fragility. · 67690f93
    Eric W. Biederman authored
    Replace the implict setting of MNT_NODEV on mounts that happen with
    just user namespace permissions with an implicit setting of SB_I_NODEV
    in s_iflags.  The visibility of the implicit MNT_NODEV has caused
    problems in the past.
    
    With this change the fragile case where an implicit MNT_NODEV needs to
    be preserved in do_remount is removed.  Using SB_I_NODEV is much less
    fragile as s_iflags are set during the original mount and never
    changed.
    
    In do_new_mount with the implicit setting of MNT_NODEV gone, the only
    code that can affect mnt_flags is fs_fully_visible so simplify the if
    statement and reduce the indentation of the code to make that clear.
    Acked-by: default avatarSeth Forshee <seth.forshee@canonical.com>
    Signed-off-by: default avatar"Eric W. Biederman" <ebiederm@xmission.com>
    67690f93
super.c 36.6 KB