fuse: fix uninitialized flags in pipe_buffer

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Fixes: d82718e348 ("fuse_dev_splice_read(): switch to add_to_pipe()")
Cc: <stable@vger.kernel.org> # 4.9+

fs/fuse/dev.c

@@ -1376,6 +1376,7 @@ static ssize_t fuse_dev_splice_read(struct file *in, loff_t *ppos,
 		 * code can Oops if the buffer persists after module unload.
 		 */
 		bufs[page_nr].ops = &nosteal_pipe_buf_ops;
+		bufs[page_nr].flags = 0;
 		ret = add_to_pipe(pipe, &bufs[page_nr++]);
 		if (unlikely(ret < 0))
 			break;