fix for breakage in #work.fd this window

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Merge tag 'pull-work.fd-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull file descriptor fix from Al Viro:
 "Fix for breakage in #work.fd this window"

* tag 'pull-work.fd-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fix the breakage in close_fd_get_file() calling conventions change

drivers/android/binder.c

@@ -1886,6 +1886,8 @@ static void binder_deferred_fd_close(int fd)
 	init_task_work(&twcb->twork, binder_do_fd_close);
 	twcb->file = close_fd_get_file(fd);
 	if (twcb->file) {
+		// pin it until binder_do_fd_close(); see comments there
+		get_file(twcb->file);
 		filp_close(twcb->file, current->files);
 		task_work_add(current, &twcb->twork, TWA_RESUME);
 	} else {

fs/file.c

@@ -800,8 +800,7 @@ struct file *__close_fd_get_file(unsigned int fd)
 
 /*
  * variant of close_fd that gets a ref on the file for later fput.
- * The caller must ensure that filp_close() called on the file, and then
- * an fput().
+ * The caller must ensure that filp_close() called on the file.
  */
 struct file *close_fd_get_file(unsigned int fd)
 {

fs/io_uring.c

@@ -6010,7 +6010,7 @@ static int io_close(struct io_kiocb *req, unsigned int issue_flags)
 	struct files_struct *files = current->files;
 	struct io_close *close = &req->close;
 	struct fdtable *fdt;
-	struct file *file = NULL;
+	struct file *file;
 	int ret = -EBADF;
 
 	if (req->close.file_slot) {
@@ -6029,7 +6029,6 @@ static int io_close(struct io_kiocb *req, unsigned int issue_flags)
 			lockdep_is_held(&files->file_lock));
 	if (!file || file->f_op == &io_uring_fops) {
 		spin_unlock(&files->file_lock);
-		file = NULL;
 		goto err;
 	}
 
@@ -6049,8 +6048,6 @@ static int io_close(struct io_kiocb *req, unsigned int issue_flags)
 err:
 	if (ret < 0)
 		req_set_fail(req);
-	if (file)
-		fput(file);
 	__io_req_complete(req, issue_flags, ret, 0);
 	return 0;
 }