From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1958AC432C0 for ; Fri, 22 Nov 2019 10:17:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EC49C2070E for ; Fri, 22 Nov 2019 10:17:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726526AbfKVKRY (ORCPT ); Fri, 22 Nov 2019 05:17:24 -0500 Received: from mx2.suse.de ([195.135.220.15]:46886 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726500AbfKVKRY (ORCPT ); Fri, 22 Nov 2019 05:17:24 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id C43EBAC46; Fri, 22 Nov 2019 10:17:22 +0000 (UTC) From: Jiri Slaby To: gregkh@linuxfoundation.org Cc: linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, Jiri Slaby , Sudip Mukherjee Subject: [PATCH] tty: don't crash in tty_init_dev when missing tty_port Date: Fri, 22 Nov 2019 11:17:21 +0100 Message-Id: <20191122101721.7222-1-jslaby@suse.cz> X-Mailer: git-send-email 2.24.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-serial-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org We currently warn the user when tty->port is not set in tty_init_dev yet. The warning says that the kernel will crash later. And it really will only few lines below at: tty->port->itty = tty; So be nice and avoid the crash -- return an error instead. And update the warning. Signed-off-by: Jiri Slaby Cc: Sudip Mukherjee --- drivers/tty/tty_io.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c index cb6370906a6d..d9f54c7d94f2 100644 --- a/drivers/tty/tty_io.c +++ b/drivers/tty/tty_io.c @@ -1345,9 +1345,12 @@ struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx) if (!tty->port) tty->port = driver->ports[idx]; - WARN_RATELIMIT(!tty->port, - "%s: %s driver does not set tty->port. This will crash the kernel later. Fix the driver!\n", - __func__, tty->driver->name); + if (WARN_RATELIMIT(!tty->port, + "%s: %s driver does not set tty->port. This would crash the kernel. Fix the driver!\n", + __func__, tty->driver->name)) { + retval = -EINVAL; + goto err_release_lock; + } retval = tty_ldisc_lock(tty, 5 * HZ); if (retval) -- 2.24.0