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=-13.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_2 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 6A439C34047 for ; Wed, 19 Feb 2020 09:56:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4B1322464E for ; Wed, 19 Feb 2020 09:56:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726491AbgBSJ4d (ORCPT ); Wed, 19 Feb 2020 04:56:33 -0500 Received: from mx2.suse.de ([195.135.220.15]:35564 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726385AbgBSJ4d (ORCPT ); Wed, 19 Feb 2020 04:56:33 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 2D3AEAD93; Wed, 19 Feb 2020 09:56:31 +0000 (UTC) Message-ID: <1582106185.9787.9.camel@suse.com> Subject: Re: usb cdc-acm TIOCSSERIAL may wrongly report EPERM From: Oliver Neukum To: Anthony Mallet Cc: linux-usb@vger.kernel.org Date: Wed, 19 Feb 2020 10:56:25 +0100 In-Reply-To: <24140.5498.228141.264272@beetle.laas.fr> References: <24140.5498.228141.264272@beetle.laas.fr> Content-Type: multipart/mixed; boundary="=-A0aR9OY6X058HHBTCulz" X-Mailer: Evolution 3.26.6 Mime-Version: 1.0 Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org --=-A0aR9OY6X058HHBTCulz Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Am Dienstag, den 18.02.2020, 17:48 +0100 schrieb Anthony Mallet: > Hi, > > A TIOCSSERIAL ioctl(2) performed on a file descriptor corresponding to > a cdc-acm driver may wrongly report EPERM even when no CAP_SYS_ADMIN > is required. This concerns almost all recent kernel versions, as I > explain below. Hi, thank you for the detailed report about an unusual bug. Could you test the attached patch? I have taken the liberty of presuming to add your 'Reported-and-tested-by'. 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