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=-11.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 364DFC3A589 for ; Thu, 15 Aug 2019 12:50:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 09DFA208C2 for ; Thu, 15 Aug 2019 12:50:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565873439; bh=e0UQzUnilCDjDURCSwkzYJCs8uJKkoKu+0Nhprakhcs=; h=Subject:To:From:Date:List-ID:From; b=eIfmqjgBvC7vTMBC7ULy2kloZ+hpLg7ICUZ/550ROIDhDnCQqr1q20+Hp9iqu1NwY 5F1i1GFdWRQOYm9aFxHlvvv59ICDJ3V34Cmp6w4QepRNQDRbTZWZzdXQvcCU8kJmYA mV7Nf3Ng7Hv0S8J3li3bGd6N0CCy5k2motdoc96s= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731243AbfHOMui (ORCPT ); Thu, 15 Aug 2019 08:50:38 -0400 Received: from mail.kernel.org ([198.145.29.99]:38096 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730379AbfHOMui (ORCPT ); Thu, 15 Aug 2019 08:50:38 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 077C72084D; Thu, 15 Aug 2019 12:50:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1565873437; bh=e0UQzUnilCDjDURCSwkzYJCs8uJKkoKu+0Nhprakhcs=; h=Subject:To:From:Date:From; b=VdtPLMPG+sZymyp7md1rZzSwKN/OyQNhjKPdEIyYgTgN43+1mT9bVTdp0lzWOUVBR Q67NUrUKTGUAiQvjD802roM8BdVRLQMKpq1VLiGajh/qaiVjXVKEnF9T3CM5gKC7Cp ZBzT7vUWdPOLAK+1D7DZeC22IerOCUyyEUnGC0Ps= Subject: patch "usb: cdc-acm: make sure a refcount is taken early enough" added to usb-linus To: oneukum@suse.com, gregkh@linuxfoundation.org, stable@vger.kernel.org From: Date: Thu, 15 Aug 2019 14:50:35 +0200 Message-ID: <156587343520832@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org This is a note to let you know that I've just added the patch titled usb: cdc-acm: make sure a refcount is taken early enough to my usb git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git in the usb-linus branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will hopefully also be merged in Linus's tree for the next -rc kernel release. If you have any questions about this process, please let me know. >From c52873e5a1ef72f845526d9f6a50704433f9c625 Mon Sep 17 00:00:00 2001 From: Oliver Neukum Date: Thu, 8 Aug 2019 16:21:19 +0200 Subject: usb: cdc-acm: make sure a refcount is taken early enough destroy() will decrement the refcount on the interface, so that it needs to be taken so early that it never undercounts. Fixes: 7fb57a019f94e ("USB: cdc-acm: Fix potential deadlock (lockdep warning)") Cc: stable Reported-and-tested-by: syzbot+1b2449b7b5dc240d107a@syzkaller.appspotmail.com Signed-off-by: Oliver Neukum Link: https://lore.kernel.org/r/20190808142119.7998-1-oneukum@suse.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/class/cdc-acm.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index 183b41753c98..62f4fb9b362f 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -1301,10 +1301,6 @@ static int acm_probe(struct usb_interface *intf, tty_port_init(&acm->port); acm->port.ops = &acm_port_ops; - minor = acm_alloc_minor(acm); - if (minor < 0) - goto alloc_fail1; - ctrlsize = usb_endpoint_maxp(epctrl); readsize = usb_endpoint_maxp(epread) * (quirks == SINGLE_RX_URB ? 1 : 2); @@ -1312,6 +1308,13 @@ static int acm_probe(struct usb_interface *intf, acm->writesize = usb_endpoint_maxp(epwrite) * 20; acm->control = control_interface; acm->data = data_interface; + + usb_get_intf(acm->control); /* undone in destruct() */ + + minor = acm_alloc_minor(acm); + if (minor < 0) + goto alloc_fail1; + acm->minor = minor; acm->dev = usb_dev; if (h.usb_cdc_acm_descriptor) @@ -1458,7 +1461,6 @@ static int acm_probe(struct usb_interface *intf, usb_driver_claim_interface(&acm_driver, data_interface, acm); usb_set_intfdata(data_interface, acm); - usb_get_intf(control_interface); tty_dev = tty_port_register_device(&acm->port, acm_tty_driver, minor, &control_interface->dev); if (IS_ERR(tty_dev)) { -- 2.22.1