• Miklos Szeredi's avatar
    vfs: allow unprivileged whiteout creation · a3c751a5
    Miklos Szeredi authored
    Whiteouts, unlike real device node should not require privileges to create.
    
    The general concern with device nodes is that opening them can have side
    effects.  The kernel already avoids zero major (see
    Documentation/admin-guide/devices.txt).  To be on the safe side the patch
    explicitly forbids registering a char device with 0/0 number (see
    cdev_add()).
    
    This guarantees that a non-O_PATH open on a whiteout will fail with ENODEV;
    i.e. it won't have any side effect.
    Signed-off-by: default avatarMiklos Szeredi <mszeredi@redhat.com>
    a3c751a5
char_dev.c 16.5 KB