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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 83106C3A5A1 for ; Thu, 22 Aug 2019 17:23:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 50B3723406 for ; Thu, 22 Aug 2019 17:23:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1566494604; bh=0C0CntLjrth/EChT8V7C04HBrtlfZujJ18utphkB0Vg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=rrzvnnZ3gJSPNmuWiKQWbCmiLlZdvFSrqNYpucS5c+fBItQEjWR4C0wMIFHExNxx6 NKK5Rl6Tguu9ge8kj9j+apMdq6LE/SGwn7KFqwXjT5rrM0HxHG/pAjaXo5tfVyuFgy WKY4LbsobhqBQNuq/vICgykbBtoPB9OVRdnkJxe4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2403934AbfHVRXX (ORCPT ); Thu, 22 Aug 2019 13:23:23 -0400 Received: from mail.kernel.org ([198.145.29.99]:42878 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2403898AbfHVRXT (ORCPT ); Thu, 22 Aug 2019 13:23:19 -0400 Received: from localhost (wsip-184-188-36-2.sd.sd.cox.net [184.188.36.2]) (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 67284233FC; Thu, 22 Aug 2019 17:23:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1566494598; bh=0C0CntLjrth/EChT8V7C04HBrtlfZujJ18utphkB0Vg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=YA/3I4eG7J5m2qb1Z8tQyN7Wa60cyX9XbgYZWAtPRaSqF+5heeMqJ7Z1OzDo/T2Um UfabuxnSm2i2ZB0h/Npf8CSH2PR+S2Gcgurw0KhmRXqRF4j5cfNaX7Js6xNnb0U40g 16vDJPFbF+KBcqfMHdhfanUPKlrfCI+4FQR5d4fc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+a64a382964bf6c71a9c0@syzkaller.appspotmail.com, Oliver Neukum Subject: [PATCH 4.9 002/103] usb: iowarrior: fix deadlock on disconnect Date: Thu, 22 Aug 2019 10:17:50 -0700 Message-Id: <20190822171728.557363694@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190822171728.445189830@linuxfoundation.org> References: <20190822171728.445189830@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Oliver Neukum commit c468a8aa790e0dfe0a7f8a39db282d39c2c00b46 upstream. We have to drop the mutex before we close() upon disconnect() as close() needs the lock. This is safe to do by dropping the mutex as intfdata is already set to NULL, so open() will fail. Fixes: 03f36e885fc26 ("USB: open disconnect race in iowarrior") Reported-by: syzbot+a64a382964bf6c71a9c0@syzkaller.appspotmail.com Cc: stable Signed-off-by: Oliver Neukum Link: https://lore.kernel.org/r/20190808092728.23417-1-oneukum@suse.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/misc/iowarrior.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) --- a/drivers/usb/misc/iowarrior.c +++ b/drivers/usb/misc/iowarrior.c @@ -886,19 +886,20 @@ static void iowarrior_disconnect(struct dev = usb_get_intfdata(interface); mutex_lock(&iowarrior_open_disc_lock); usb_set_intfdata(interface, NULL); + /* prevent device read, write and ioctl */ + dev->present = 0; minor = dev->minor; + mutex_unlock(&iowarrior_open_disc_lock); + /* give back our minor - this will call close() locks need to be dropped at this point*/ - /* give back our minor */ usb_deregister_dev(interface, &iowarrior_class); mutex_lock(&dev->mutex); /* prevent device read, write and ioctl */ - dev->present = 0; mutex_unlock(&dev->mutex); - mutex_unlock(&iowarrior_open_disc_lock); if (dev->opened) { /* There is a process that holds a filedescriptor to the device ,