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=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 2B09FC46469 for ; Wed, 12 Sep 2018 15:02:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CC08520890 for ; Wed, 12 Sep 2018 15:02:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CC08520890 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arndb.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728225AbeILUHJ (ORCPT ); Wed, 12 Sep 2018 16:07:09 -0400 Received: from mout.kundenserver.de ([212.227.126.130]:52626 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727804AbeILUHI (ORCPT ); Wed, 12 Sep 2018 16:07:08 -0400 Received: from wuerfel.lan ([109.193.40.16]) by mrelayeu.kundenserver.de (mreue002 [212.227.15.129]) with ESMTPA (Nemesis) id 0MHfXI-1fz0Bb1MVw-003Iuh; Wed, 12 Sep 2018 17:01:47 +0200 From: Arnd Bergmann To: viro@zeniv.linux.org.uk Cc: linux-fsdevel@vger.kernel.org, Arnd Bergmann , linux-kernel@vger.kernel.org Subject: [PATCH v2 01/17] compat_ioctl: add generic_compat_ioctl_ptrarg() Date: Wed, 12 Sep 2018 17:01:02 +0200 Message-Id: <20180912150142.157913-1-arnd@arndb.de> X-Mailer: git-send-email 2.18.0 X-Provags-ID: V03:K1:wz6vo7KIM91kt111ot1ATETat4nUfGMJb8FLy77lzIOkc5wfyKu wZ0kYboXWyxsU5awQ3oUor82AlfAk3f/J5do+S5nfBJ3NEq3BC0adeGjkRg7oKf9xNDEut+ G3FwLM38ozOo3reZvfH6A0GecwDdx0aFfDjei3/mnJfoAnAYXWrLzMYPVK1RiOrbUWIXLNr HK0bIJ/e46ESuPiBdwWoA== X-UI-Out-Filterresults: notjunk:1;V01:K0:aeLDAMsSyZE=:TVJ+SS9XztZ8PspfoWbgn/ QNGobgx/T3o6iRMkQ3R0C7VYzxGUQaCkU5TKbbUzzcePfqFWWa/LkJEtrcf0mBBN2sh9GZ6UO B9aiG2BtIaOs2ABbhYn9UurSrwk7wF21ZFJSz9Vw6sHR7Vh/nni9/XqVCaFqj3lhNtwIrXIbi scBywI3tltnx7LSQ55lcGl3TaKa94zB6Iu8ct08cbFy6wuzvFgWnw+3KF5Hr1/vex8+JEhuYe fPO66u961mjnEJLXTfE8e8gCuU0twUPBBp+VP42gRGBzoLI+jo1ge4BcgYdATtwND7qjsfR6G xXyJfCbYx/wM9QnOfoOUjC3UcCKe8hwUgpg8eHLCz5ZMxfjhjANZRgGEDL2OlFDNKWcI5gNsx uLl/OFqG/+3Fk5DOnFWC9Nnf0fWXJCJnYHRzoJ/Yi51o1RGHIxEyUmgywAmboS4zo7+NLHBMs 1uMFkDA4Wh+gRsF8fVMZ9wLNItKcISagcEFdgyaAISXgWPzHGMuMepzUYU1rfongDROfjJqIO UqpWXHDWAi4tmqX+0xU/RJNdbX6KxlPiePnRHcSSGsR6wDSKoXB7DrNBuvu38Q6xQzByqzooc Oma7aA+m3VDKkLZ8nnTW3ZHZ1dG0uGy2fK0qmMtb5uVzfLBNxH5OJNEy31SX5I9ngKmGSKfMt tzcmXYpqgCXAVsOVBqzBA9MhfmifdHfENpWA62tuFN5bgATU5l2YCe/h31cVpmhv0cUY= Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Many drivers have ioctl() handlers that are completely compatible between 32-bit and 64-bit architectures, except for the argument that is passed down from user space and may have to be passed through compat_ptr() in order to become a valid 64-bit pointer. Using ".compat_ptr=generic_compat_ioctl_ptrarg" in file operations should let us simplify a lot of those drivers to avoid #ifdef checks, and convert additional drivers that don't have proper compat handling yet. Signed-off-by: Arnd Bergmann --- fs/compat_ioctl.c | 10 ++++++++++ include/linux/fs.h | 7 +++++++ 2 files changed, 17 insertions(+) diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c index a9b00942e87d..2d7c7e149083 100644 --- a/fs/compat_ioctl.c +++ b/fs/compat_ioctl.c @@ -122,6 +122,16 @@ get_user(val, srcptr) || put_user(val, dstptr); \ }) +/* helper function to avoid trivial compat_ioctl() implementations */ +long generic_compat_ioctl_ptrarg(struct file *file, unsigned int cmd, unsigned long arg) +{ + if (!file->f_op->unlocked_ioctl) + return -ENOIOCTLCMD; + + return file->f_op->unlocked_ioctl(file, cmd, (unsigned long)compat_ptr(arg)); +} +EXPORT_SYMBOL_GPL(generic_compat_ioctl_ptrarg); + static int do_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { int err; diff --git a/include/linux/fs.h b/include/linux/fs.h index 33322702c910..18a90aa2dc93 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1643,6 +1643,13 @@ int vfs_mkobj(struct dentry *, umode_t, extern long vfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg); +#ifdef CONFIG_COMPAT +extern long generic_compat_ioctl_ptrarg(struct file *file, unsigned int cmd, + unsigned long arg); +#else +#define generic_compat_ioctl_ptrarg NULL +#endif + /* * VFS file helper functions. */ -- 2.18.0