Merge tag 'pull-fd' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull 'struct fd' class updates from Al Viro:
 "The bulk of struct fd memory safety stuff

  Making sure that struct fd instances are destroyed in the same scope
  where they'd been created, getting rid of reassignments and passing
  them by reference, converting to CLASS(fd{,_pos,_raw}).

  We are getting very close to having the memory safety of that stuff
  trivial to verify"

* tag 'pull-fd' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (28 commits)
  deal with the last remaing boolean uses of fd_file()
  css_set_fork(): switch to CLASS(fd_raw, ...)
  memcg_write_event_control(): switch to CLASS(fd)
  assorted variants of irqfd setup: convert to CLASS(fd)
  do_pollfd(): convert to CLASS(fd)
  convert do_select()
  convert vfs_dedupe_file_range().
  convert cifs_ioctl_copychunk()
  convert media_request_get_by_fd()
  convert spu_run(2)
  switch spufs_calls_{get,put}() to CLASS() use
  convert cachestat(2)
  convert do_preadv()/do_pwritev()
  fdget(), more trivial conversions
  fdget(), trivial conversions
  privcmd_ioeventfd_assign(): don't open-code eventfd_ctx_fdget()
  o2hb_region_dev_store(): avoid goto around fdget()/fdput()
  introduce "fd_pos" class, convert fdget_pos() users to it.
  fdget_raw() users: switch to CLASS(fd_raw)
  convert vmsplice() to CLASS(fd)
  ...

kernel/module/main.c

@@ -3202,7 +3202,7 @@ static int idempotent_init_module(struct file *f, const char __user * uargs, int
 {
 	struct idempotent idem;
 
-	if (!f || !(f->f_mode & FMODE_READ))
+	if (!(f->f_mode & FMODE_READ))
 		return -EBADF;
 
 	/* Are we the winners of the race and get to do this? */
@@ -3219,10 +3219,7 @@ static int idempotent_init_module(struct file *f, const char __user * uargs, int
 
 SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
 {
-	int err;
-	struct fd f;
-
-	err = may_init_module();
+	int err = may_init_module();
 	if (err)
 		return err;
 
@@ -3233,10 +3230,10 @@ SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
 		      |MODULE_INIT_COMPRESSED_FILE))
 		return -EINVAL;
 
-	f = fdget(fd);
-	err = idempotent_init_module(fd_file(f), uargs, flags);
-	fdput(f);
-	return err;
+	CLASS(fd, f)(fd);
+	if (fd_empty(f))
+		return -EBADF;
+	return idempotent_init_module(fd_file(f), uargs, flags);
 }
 
 /* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */