From patchwork Fri Nov 6 22:17:16 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 1395985 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=kernel.org Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=default header.b=LdAmxG3U; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4CSZdR3M9qz9sSf for ; Sat, 7 Nov 2020 09:22:35 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728817AbgKFWSA (ORCPT ); Fri, 6 Nov 2020 17:18:00 -0500 Received: from mail.kernel.org ([198.145.29.99]:41094 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728055AbgKFWR5 (ORCPT ); Fri, 6 Nov 2020 17:17:57 -0500 Received: from localhost.localdomain (HSI-KBW-46-223-126-90.hsi.kabel-badenwuerttemberg.de [46.223.126.90]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D39F12087E; Fri, 6 Nov 2020 22:17:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604701077; bh=nzhWms5vuZRRAWciYsS79GiwdEaX2soiPILlN+tvJKA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LdAmxG3U4urOY/6fkI9PqtC/me9sbsLzKpCacBAVSQ/mcwfsBbJ4cpC4CV4Do2xrD aiTjAMSgGGO4/NxcBJ06LS16EiMsTOYV/EZfLjxjGYBvjTuJczVP43Oc9wqc9TIfm8 Eb7FTqm+alG3Y0CDPbAs1NPN3j4EHKQIzrGpyYf0= From: Arnd Bergmann To: netdev@vger.kernel.org Cc: Arnd Bergmann , linux-kernel@vger.kernel.org, linux-wireless@vger.kernel.org, bridge@lists.linux-foundation.org, linux-hams@vger.kernel.org, Jakub Kicinski , Christoph Hellwig , Alexander Viro , Johannes Berg , Andrew Lunn , Heiner Kallweit Subject: [RFC net-next 01/28] net: split out SIOCDEVPRIVATE handling from dev_ioctl Date: Fri, 6 Nov 2020 23:17:16 +0100 Message-Id: <20201106221743.3271965-2-arnd@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20201106221743.3271965-1-arnd@kernel.org> References: <20201106221743.3271965-1-arnd@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Arnd Bergmann SIOCDEVPRIVATE ioctl commands are mainly used in really old drivers, and they have a number of problems: - They hide behind the normal .ndo_do_ioctl function that is also used for other things in modern drivers, so it's hard to spot a driver that actually uses one of these - Since drivers use a number different calling conventions, it is impossible to support compat mode for them in a generic way. - With all drivers using the same 16 commands codes, there is no way to introspect the data being passed through things like strace. Add a new net_device_ops callback pointer, to address the first two of these. Separating them from .ndo_do_ioctl makes it easy to grep for drivers with a .ndo_siocdevprivate callback, and the unwieldy name hopefully makes it easier to spot in code review. By passing the ifreq structure and the ifr_data pointer separately, it is no longer necessary to overload these, and the driver can use either one for a given command. Signed-off-by: Arnd Bergmann --- include/linux/netdevice.h | 3 +++ net/core/dev_ioctl.c | 25 ++++++++++++++++++++++--- 2 files changed, 25 insertions(+), 3 deletions(-) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index d1b7fb1241b3..93f980e1d69b 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1301,6 +1301,9 @@ struct net_device_ops { int (*ndo_validate_addr)(struct net_device *dev); int (*ndo_do_ioctl)(struct net_device *dev, struct ifreq *ifr, int cmd); + int (*ndo_siocdevprivate)(struct net_device *dev, + struct ifreq *ifr, + void __user *data, int cmd); int (*ndo_set_config)(struct net_device *dev, struct ifmap *map); int (*ndo_change_mtu)(struct net_device *dev, diff --git a/net/core/dev_ioctl.c b/net/core/dev_ioctl.c index 5822737a78f4..58daf41a4a08 100644 --- a/net/core/dev_ioctl.c +++ b/net/core/dev_ioctl.c @@ -269,6 +269,23 @@ static int dev_do_ioctl(struct net_device *dev, return err; } +static int dev_siocdevprivate(struct net_device *dev, + struct ifreq *ifr, unsigned int cmd) +{ + const struct net_device_ops *ops = dev->netdev_ops; + void __user *data = ifr->ifr_data; + + if (ops->ndo_siocdevprivate) { + if (netif_device_present(dev)) + return ops->ndo_siocdevprivate(dev, ifr, data, cmd); + else + return -ENODEV; + } + + /* fall back to do_ioctl for drivers not yet converted */ + return dev_do_ioctl(dev, ifr, cmd); +} + /* * Perform the SIOCxIFxxx calls, inside rtnl_lock() */ @@ -346,9 +363,11 @@ static int dev_ifsioc(struct net *net, struct ifreq *ifr, unsigned int cmd) * Unknown or private ioctl */ default: - if ((cmd >= SIOCDEVPRIVATE && - cmd <= SIOCDEVPRIVATE + 15) || - cmd == SIOCBONDENSLAVE || + if (cmd >= SIOCDEVPRIVATE && + cmd <= SIOCDEVPRIVATE + 15) + return dev_siocdevprivate(dev, ifr, cmd); + + if (cmd == SIOCBONDENSLAVE || cmd == SIOCBONDRELEASE || cmd == SIOCBONDSETHWADDR || cmd == SIOCBONDSLAVEINFOQUERY ||