From patchwork Thu May 20 09:19:43 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 445727 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=-19.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, 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 99C64C433ED for ; Thu, 20 May 2021 09:55:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 80ED5613E8 for ; Thu, 20 May 2021 09:55:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234605AbhETJ4j (ORCPT ); Thu, 20 May 2021 05:56:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:54308 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234851AbhETJys (ORCPT ); Thu, 20 May 2021 05:54:48 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 91CCF613E8; Thu, 20 May 2021 09:37:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1621503425; bh=8csTBPhZNYEwpZ/JDNZfQoTGZl82h2J9l4/jiCn7/4I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FAF3KkZPmWGMwvpr4UBthCf71Sa7apYmUrVjk6NmD+/JB17aA3AgjtdDT2USgBBMe vlBibNOJC0fSvvQJMlAnqw7/rlg8JruPg8QJH/t+DCIDhCdo3use4JQyY0J+lBaQWX BsxKh7Av+fpzJBL3tix02ybcgO/6lorXTAu3Lx6k= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Oliver Neukum , Johan Hovold , Sasha Levin Subject: [PATCH 4.19 214/425] USB: cdc-acm: fix unprivileged TIOCCSERIAL Date: Thu, 20 May 2021 11:19:43 +0200 Message-Id: <20210520092138.456882105@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210520092131.308959589@linuxfoundation.org> References: <20210520092131.308959589@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Johan Hovold [ Upstream commit dd5619582d60007139f0447382d2839f4f9e339b ] TIOCSSERIAL is a horrid, underspecified, legacy interface which for most serial devices is only useful for setting the close_delay and closing_wait parameters. A non-privileged user has only ever been able to set the since long deprecated ASYNC_SPD flags and trying to change any other *supported* feature should result in -EPERM being returned. Setting the current values for any supported features should return success. Fix the cdc-acm implementation which instead indicated that the TIOCSSERIAL ioctl was not even implemented when a non-privileged user set the current values. Fixes: ba2d8ce9db0a ("cdc-acm: implement TIOCSSERIAL to avoid blocking close(2)") Acked-by: Oliver Neukum Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20210408131602.27956-3-johan@kernel.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/usb/class/cdc-acm.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index 7f4f21ba8efc..738de8c9c354 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -987,8 +987,6 @@ static int set_serial_info(struct acm *acm, if ((new_serial.close_delay != old_close_delay) || (new_serial.closing_wait != old_closing_wait)) retval = -EPERM; - else - retval = -EOPNOTSUPP; } else { acm->port.close_delay = close_delay; acm->port.closing_wait = closing_wait;