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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 0C0A7C43603 for ; Wed, 18 Dec 2019 22:18:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DE969218AC for ; Wed, 18 Dec 2019 22:18:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726700AbfLRWSK (ORCPT ); Wed, 18 Dec 2019 17:18:10 -0500 Received: from mout.kundenserver.de ([212.227.17.24]:57147 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726463AbfLRWSI (ORCPT ); Wed, 18 Dec 2019 17:18:08 -0500 Received: from mail-qv1-f53.google.com ([209.85.219.53]) by mrelayeu.kundenserver.de (mreue106 [212.227.15.145]) with ESMTPSA (Nemesis) id 1MCb2L-1iYayM1wPr-009kFD; Wed, 18 Dec 2019 23:18:05 +0100 Received: by mail-qv1-f53.google.com with SMTP id t6so1417050qvs.5; Wed, 18 Dec 2019 14:18:04 -0800 (PST) X-Gm-Message-State: APjAAAVaZD2Eg3fQdtcxD5JNcEDeSWedyMkZnQMYrHy4zAjY87Gesyih JnguV6JWq6ALfPIct0HX+dvV0SENfOwKpuyDtco= X-Google-Smtp-Source: APXvYqyDPnpRg6mwfTYotGIKOQD9lfniBnekpDffjnBEQMcvT9QFg9SCGIabTN09eE8JL5PLpkkzWzeQzawX7/VdQRw= X-Received: by 2002:a0c:bd20:: with SMTP id m32mr4714621qvg.197.1576707483927; Wed, 18 Dec 2019 14:18:03 -0800 (PST) MIME-Version: 1.0 References: <20191217221708.3730997-1-arnd@arndb.de> <20191217221708.3730997-24-arnd@arndb.de> In-Reply-To: From: Arnd Bergmann Date: Wed, 18 Dec 2019 23:17:47 +0100 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v2 23/27] compat_ioctl: move HDIO ioctl handling into drivers/ide To: Ben Hutchings Cc: Jens Axboe , "James E.J. Bottomley" , "Martin K. Petersen" , linux-scsi , linux-block , y2038 Mailman List , "linux-kernel@vger.kernel.org" , Christoph Hellwig , "open list:DOCUMENTATION" , Jonathan Corbet , Al Viro , Linux FS-devel Mailing List Content-Type: text/plain; charset="UTF-8" X-Provags-ID: V03:K1:1PWPgZSgrRh6EkOUrB3DH+xnzxWn4VChdd2c+XUEePlmPgEeiRT WBXUNhoDFsWsB3hFwrB8BWcaTMZ98sEXhl1yhopz051z3GfzrXW2sjnLGTDTOgoI7h4ZrkA Wz3r1NRM3OTTjWJyMOoGBcMyG/0eU2luHF/loRr6FvQzgmZY4FgQyKSCOUwwNZYetGTXSc3 ObsQGsD1xEzW1TOWm0zkw== X-UI-Out-Filterresults: notjunk:1;V03:K0:RCLkvQsMPHY=:VDRkTzHgQuVwKcfZTX1u3c Odf9cE7PFpDFxH3rWds5DWffyWo9xpGYD7HllVmGHIspdwdcy8OWnDb6pRjzRcR6n10keYisV 54NYj3peZVr6V5wA2l18peGWDmj/2oNEiDnNQqV4QrQkUVstQdKiwM0GUjU9fwRZvAPIa23bI ikebAXX+CkFGogZzFsE/I8FOmKMevGeslbyQkZ0A1bSygpO3h+F8YCaoz0HlcGdaQ+fJUHba1 eGZRftu6zpBq9CDHpqmPcojBvh6UvPa0IHRmLJlucWmVL88GEYDJQoQ+If9zX40UJWukt+0RT uS81BK/d6enp8kTOg2C+EK8/lLgQy/MT2S7Hq+Hxx+O1vD9MjjtDpbH4gzjTr1haxyTe7h6UJ drby9OJqq4bBuGnx/Oi8LXaUecAe/X749by6S4hbU+JzZAKpRmBW6XvMDhN5p5LbOF3O1W1pB Gyd+HaTpFjrAGa7hxcClEwNU/A5+NBig8cyg+fuLgKUFlDEYsnG2NTx/0uFQuEVFwyqM/NO+V ozWcER5O2eJfCOF7c/67Nj03gtVSaKj3NDgg4MKsiLE4UJAtqm37csxazsTgaXv7Qp2j5to3O C7ba353V33oTdnoV9ODoqWhWxBhciNbwOZp11vTPS5g7OBLzcLYLZA0SZ+JTi4jBWf5UJY2Wb 1/5L0N/zuxJuXpRYOj7W7Qy0OyDntmqjCkn6bGqJx19rNVdMjdHMjl4cNHVcPwzm77W7WrJs3 PKpnpTi8q8uD3GFPW+4nJxbZa6/DLbV0VmpbSZqYDlBC0lzNFEcuU93gd0Vcqu++u6sk2DvPv pxugqTtQ6rZ9OGTHmD641paRuungUXGui8mJUrTAHJ0x6CjQ9SAnLzWiUAg+YrjD6b1CnP4W/ DH3Ifk4KJjOivfjXflFw== Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Dec 18, 2019 at 10:11 PM Ben Hutchings wrote: > On Tue, 2019-12-17 at 23:17 +0100, Arnd Bergmann wrote: > > Most of the HDIO ioctls are only used by the obsolete drivers/ide > > subsystem, these can be handled by changing ide_cmd_ioctl() to be aware > > of compat mode and doing the correct transformations in place and using > > it as both native and compat handlers for all drivers. > > > > The SCSI drivers implementing the same commands are already doing > > this in the drivers, so the compat_blkdev_driver_ioctl() function > > is no longer needed now. > > > > The BLKSECTSET and HDIO_GETGEO_BIG ioctls are not implemented > > in any driver any more and no longer need any conversion. > [...] > > I noticed that HDIO_DRIVE_TASKFILE, handled by ide_taskfile_ioctl() in > drivers/ide/ide-taskfile.c, never had compat handling before. After > this patch it does, but its argument isn't passed through compat_ptr(). > Again, doesn't really matter because IDE isn't a thing on s390. I checked again, and I think it's worse than that: ide_taskfile_ioctl() takes an ide_task_request_t argument, which is not compatible at all (it has two long members). I suspect what happened here is that I confused it with ide_cmd_ioctl(), which takes a 'struct ide_taskfile' argument that /is/ compatible. I don't think there is a point in adding a handler now: most users of drivers/ide are 32-bit only, and nobody complained so far, but I would add this change if you agree: diff --git a/drivers/ide/ide-ioctls.c b/drivers/ide/ide-ioctls.c index f6497c817493..83afee3983fe 100644 --- a/drivers/ide/ide-ioctls.c +++ b/drivers/ide/ide-ioctls.c @@ -270,6 +270,9 @@ int generic_ide_ioctl(ide_drive_t *drive, struct block_device *bdev, case HDIO_DRIVE_TASKFILE: if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) return -EACCES; + /* missing compat handler for HDIO_DRIVE_TASKFILE */ + if (in_compat_syscall()) + return -ENOTTY; if (drive->media == ide_disk) return ide_taskfile_ioctl(drive, arg); return -ENOMSG; Arnd