On Mon, Jul 13, 2020 at 04:45:12PM +0800, Hillf Danton wrote: > Bridge the gap between slab free and the fput in task work wrt > file's private data.
No. This
> @@ -2048,6 +2055,7 @@ SYSCALL_DEFINE1(userfaultfd, int, flags)
>
> fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC);
> if (fd < 0) {
> + file->private_data = NULL;
> fput(file);
> goto out;
> }
>
is fundamentally wrong; you really shouldn't take over the cleanups
if you ever do fput().
