From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Subject: Re: [PATCH 04/14] x86: use more conventional access_ok() definition Date: Mon, 14 Feb 2022 21:00:11 +0100 Message-ID: <20220214200011.GA3786@lst.de> References: <20220214163452.1568807-1-arnd@kernel.org> <20220214163452.1568807-5-arnd@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=UhnY8KAe59qhpZ0jXwVt0pKEl8AP7HoKciOb72NzlHA=; b=EIU9NdwxFypV8O uT5FXr6DO3GUBlfOXdl9u90Z6JBazjfCYte/KXF7qrM0E973NMqiPl8qYG+gmzee0/7WgYF4TBXGk 6Wb3J1heakLOvbfoBxtHisGLBfTrJQgSPicEI7Sr+lMSE9jKwM9D2LVhvZqPR2XOmy6zegOdnN95C cxyAmxYVU1IlldVXzOeEUiRuC77K/UYE0JzU8j5zB+3umO1K18t2TOkWpYKFFbeMkF/6o8u9RqyjR QDptb8z0NquQC8VSmKZU3cyrG59R698YrBJjwOv+QFk+FWLRwiW0GRbMOqLK+ihmY0j6UUF6iUMcT BnJkfZB73lGu/Pu8kIkQ==; Content-Disposition: inline In-Reply-To: List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+glpr-linux-riscv=m.gmane-mx.org@lists.infradead.org To: Arnd Bergmann Cc: Christoph Hellwig , Linus Torvalds , Christoph Hellwig , linux-arch , Linux-MM , Linux API , Arnd Bergmann , Linux Kernel Mailing List , Mark Rutland , Rich Felker , linux-ia64@vger.kernel.org, Linux-sh list , Peter Zijlstra , Max Filippov , Guo Ren , sparclinux , "open list:QUALCOMM HEXAGON..." , linux-riscv , Will Deacon , Ard Biesheuvel , linux-s390 , Brian Cain , Helge Deller On Mon, Feb 14, 2022 at 08:45:52PM +0100, Arnd Bergmann wrote: > As Al pointed out, they turned out to be necessary on sparc64, but the only > definitions are on sparc64 and x86, so it's possible that they serve a similar > purpose here, in which case changing the limit from TASK_SIZE to > TASK_SIZE_MAX is probably wrong as well. > > So either I need to revert the original definition as I did on sparc64, or > they can be removed completely. Hopefully Al or the x86 maintainers > can clarify. Looking at the x86 users I think: - valid_user_frame should go away and the caller should use get_user instead of __get_user - the one in copy_code can just go away, as there is another check in copy_from_user_nmi - copy_stack_frame should just use access_ok - as does copy_from_user_nmi but yes, having someone who actually knows this code look over it would be very helpful. 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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2474DC433FE for ; Mon, 14 Feb 2022 20:17:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229825AbiBNURy (ORCPT ); Mon, 14 Feb 2022 15:17:54 -0500 Received: from gmail-smtp-in.l.google.com ([23.128.96.19]:56444 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229823AbiBNURx (ORCPT ); Mon, 14 Feb 2022 15:17:53 -0500 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 20A4A192B2; Mon, 14 Feb 2022 12:17:36 -0800 (PST) Received: by verein.lst.de (Postfix, from userid 2407) id 2A25C68AA6; Mon, 14 Feb 2022 21:00:11 +0100 (CET) Date: Mon, 14 Feb 2022 21:00:11 +0100 From: Christoph Hellwig To: Arnd Bergmann Cc: Christoph Hellwig , Linus Torvalds , Christoph Hellwig , linux-arch , Linux-MM , Linux API , Arnd Bergmann , Linux Kernel Mailing List , Mark Rutland , Rich Felker , linux-ia64@vger.kernel.org, Linux-sh list , Peter Zijlstra , Max Filippov , Guo Ren , sparclinux , "open list:QUALCOMM HEXAGON..." , linux-riscv , Will Deacon , Ard Biesheuvel , linux-s390 , Brian Cain , Helge Deller , the arch/x86 maintainers , Russell King - ARM Linux , linux-csky@vger.kernel.org, Ingo Molnar , Geert Uytterhoeven , "open list:SYNOPSYS ARC ARCHITECTURE" , "open list:TENSILICA XTENSA PORT (xtensa)" , Heiko Carstens , alpha , linux-um , linux-m68k , Openrisc , Greentime Hu , Stafford Horne , Linux ARM , Michal Simek , Thomas Bogendoerfer , Parisc List , Nick Hu , "open list:BROADCOM NVRAM DRIVER" , Dinh Nguyen , "Eric W . Biederman" , Richard Weinberger , Andrew Morton , linuxppc-dev , David Miller , Al Viro Subject: Re: [PATCH 04/14] x86: use more conventional access_ok() definition Message-ID: <20220214200011.GA3786@lst.de> References: <20220214163452.1568807-1-arnd@kernel.org> <20220214163452.1568807-5-arnd@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Precedence: bulk List-ID: X-Mailing-List: linux-api@vger.kernel.org On Mon, Feb 14, 2022 at 08:45:52PM +0100, Arnd Bergmann wrote: > As Al pointed out, they turned out to be necessary on sparc64, but the only > definitions are on sparc64 and x86, so it's possible that they serve a similar > purpose here, in which case changing the limit from TASK_SIZE to > TASK_SIZE_MAX is probably wrong as well. > > So either I need to revert the original definition as I did on sparc64, or > they can be removed completely. Hopefully Al or the x86 maintainers > can clarify. Looking at the x86 users I think: - valid_user_frame should go away and the caller should use get_user instead of __get_user - the one in copy_code can just go away, as there is another check in copy_from_user_nmi - copy_stack_frame should just use access_ok - as does copy_from_user_nmi but yes, having someone who actually knows this code look over it would be very helpful. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Date: Mon, 14 Feb 2022 20:00:11 +0000 Subject: Re: [PATCH 04/14] x86: use more conventional access_ok() definition Message-Id: <20220214200011.GA3786@lst.de> List-Id: References: <20220214163452.1568807-1-arnd@kernel.org> <20220214163452.1568807-5-arnd@kernel.org> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Arnd Bergmann Cc: Christoph Hellwig , Linus Torvalds , Christoph Hellwig , linux-arch , Linux-MM , Linux API , Arnd Bergmann , Linux Kernel Mailing List , Mark Rutland , Rich Felker , linux-ia64@vger.kernel.org, Linux-sh list , Peter Zijlstra , Max Filippov , Guo Ren , sparclinux , "open list:QUALCOMM HEXAGON..." , linux-riscv , Will Deacon , Ard Biesheuvel , linux-s390 , Brian Cain , Helge Deller , the arch/x86 maintainers , Russell King - ARM Linux , linux-csky@vger.kernel.org, Ingo Molnar , Geert Uytterhoeven , "open list:SYNOPSYS ARC ARCHITECTURE" , "open list:TENSILICA XTENSA PORT (xtensa)" , Heiko Carstens , alpha , linux-um , linux-m68k , Openrisc , Greentime Hu , Stafford Horne , Linux ARM , Michal Simek , Thomas Bogendoerfer , Parisc List , Nick Hu , "open list:BROADCOM NVRAM DRIVER" , Dinh Nguyen , "Eric W . Biederman" , Richard Weinberger , Andrew Morton , linuxppc-dev , David Miller , Al Viro On Mon, Feb 14, 2022 at 08:45:52PM +0100, Arnd Bergmann wrote: > As Al pointed out, they turned out to be necessary on sparc64, but the only > definitions are on sparc64 and x86, so it's possible that they serve a similar > purpose here, in which case changing the limit from TASK_SIZE to > TASK_SIZE_MAX is probably wrong as well. > > So either I need to revert the original definition as I did on sparc64, or > they can be removed completely. Hopefully Al or the x86 maintainers > can clarify. Looking at the x86 users I think: - valid_user_frame should go away and the caller should use get_user instead of __get_user - the one in copy_code can just go away, as there is another check in copy_from_user_nmi - copy_stack_frame should just use access_ok - as does copy_from_user_nmi but yes, having someone who actually knows this code look over it would be very helpful. 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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 21EC1C433FE for ; Mon, 14 Feb 2022 20:00:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=UhnY8KAe59qhpZ0jXwVt0pKEl8AP7HoKciOb72NzlHA=; b=EIU9NdwxFypV8O uT5FXr6DO3GUBlfOXdl9u90Z6JBazjfCYte/KXF7qrM0E973NMqiPl8qYG+gmzee0/7WgYF4TBXGk 6Wb3J1heakLOvbfoBxtHisGLBfTrJQgSPicEI7Sr+lMSE9jKwM9D2LVhvZqPR2XOmy6zegOdnN95C cxyAmxYVU1IlldVXzOeEUiRuC77K/UYE0JzU8j5zB+3umO1K18t2TOkWpYKFFbeMkF/6o8u9RqyjR QDptb8z0NquQC8VSmKZU3cyrG59R698YrBJjwOv+QFk+FWLRwiW0GRbMOqLK+ihmY0j6UUF6iUMcT BnJkfZB73lGu/Pu8kIkQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nJhWL-00GlHK-3v; Mon, 14 Feb 2022 20:00:25 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nJhWH-00GlDl-7i; Mon, 14 Feb 2022 20:00:23 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 2A25C68AA6; Mon, 14 Feb 2022 21:00:11 +0100 (CET) Date: Mon, 14 Feb 2022 21:00:11 +0100 From: Christoph Hellwig To: Arnd Bergmann Cc: Christoph Hellwig , Linus Torvalds , Christoph Hellwig , linux-arch , Linux-MM , Linux API , Arnd Bergmann , Linux Kernel Mailing List , Mark Rutland , Rich Felker , linux-ia64@vger.kernel.org, Linux-sh list , Peter Zijlstra , Max Filippov , Guo Ren , sparclinux , "open list:QUALCOMM HEXAGON..." , linux-riscv , Will Deacon , Ard Biesheuvel , linux-s390 , Brian Cain , Helge Deller , the arch/x86 maintainers , Russell King - ARM Linux , linux-csky@vger.kernel.org, Ingo Molnar , Geert Uytterhoeven , "open list:SYNOPSYS ARC ARCHITECTURE" , "open list:TENSILICA XTENSA PORT (xtensa)" , Heiko Carstens , alpha , linux-um , linux-m68k , Openrisc , Greentime Hu , Stafford Horne , Linux ARM , Michal Simek , Thomas Bogendoerfer , Parisc List , Nick Hu , "open list:BROADCOM NVRAM DRIVER" , Dinh Nguyen , "Eric W . Biederman" , Richard Weinberger , Andrew Morton , linuxppc-dev , David Miller , Al Viro Subject: Re: [PATCH 04/14] x86: use more conventional access_ok() definition Message-ID: <20220214200011.GA3786@lst.de> References: <20220214163452.1568807-1-arnd@kernel.org> <20220214163452.1568807-5-arnd@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220214_120021_449086_4CBF2F5B X-CRM114-Status: GOOD ( 20.59 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org On Mon, Feb 14, 2022 at 08:45:52PM +0100, Arnd Bergmann wrote: > As Al pointed out, they turned out to be necessary on sparc64, but the only > definitions are on sparc64 and x86, so it's possible that they serve a similar > purpose here, in which case changing the limit from TASK_SIZE to > TASK_SIZE_MAX is probably wrong as well. > > So either I need to revert the original definition as I did on sparc64, or > they can be removed completely. Hopefully Al or the x86 maintainers > can clarify. Looking at the x86 users I think: - valid_user_frame should go away and the caller should use get_user instead of __get_user - the one in copy_code can just go away, as there is another check in copy_from_user_nmi - copy_stack_frame should just use access_ok - as does copy_from_user_nmi but yes, having someone who actually knows this code look over it would be very helpful. _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv 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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 94C92C433F5 for ; Mon, 14 Feb 2022 20:00:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=I6H5G9QmRc/zdzGP3FJqMrrIl1yKOzmfx0Cfn8i8spk=; b=TYSaUwFTAACN4N MR1kyhsNwqakI4z0b4IcTjZMEBH+RGGqQlUn5PkASQJkvCjqe6cBrD6JGCWpz3DYMcd3aZKbVN7Eb tIAlvXgB+1cT80OufnijSAEp9ejgzIKs7elaA8xhFjsxzTxQMeveY1JiTJ1xAnsDPdar5wEFgM//J Sj7MImit7QK2C3PGFoFQKmRd+CrRnGsNdsVv1B2BtHfVzgGi4jJDskVakBpMIx3uVL6Q1KzxfIJbO Gt1iLY5olzPPjPBdBZRbqVmyg+x5K+gaM5ht1A/mk9bZqo0Vjg1UMurlJ/szTy1xEJnxXek3uxCyI rlPCQFzgGky1aCpcBexg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nJhWN-00GlIX-11; Mon, 14 Feb 2022 20:00:27 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nJhWH-00GlDl-7i; Mon, 14 Feb 2022 20:00:23 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 2A25C68AA6; Mon, 14 Feb 2022 21:00:11 +0100 (CET) Date: Mon, 14 Feb 2022 21:00:11 +0100 From: Christoph Hellwig To: Arnd Bergmann Cc: Christoph Hellwig , Linus Torvalds , Christoph Hellwig , linux-arch , Linux-MM , Linux API , Arnd Bergmann , Linux Kernel Mailing List , Mark Rutland , Rich Felker , linux-ia64@vger.kernel.org, Linux-sh list , Peter Zijlstra , Max Filippov , Guo Ren , sparclinux , "open list:QUALCOMM HEXAGON..." , linux-riscv , Will Deacon , Ard Biesheuvel , linux-s390 , Brian Cain , Helge Deller , the arch/x86 maintainers , Russell King - ARM Linux , linux-csky@vger.kernel.org, Ingo Molnar , Geert Uytterhoeven , "open list:SYNOPSYS ARC ARCHITECTURE" , "open list:TENSILICA XTENSA PORT (xtensa)" , Heiko Carstens , alpha , linux-um , linux-m68k , Openrisc , Greentime Hu , Stafford Horne , Linux ARM , Michal Simek , Thomas Bogendoerfer , Parisc List , Nick Hu , "open list:BROADCOM NVRAM DRIVER" , Dinh Nguyen , "Eric W . Biederman" , Richard Weinberger , Andrew Morton , linuxppc-dev , David Miller , Al Viro Subject: Re: [PATCH 04/14] x86: use more conventional access_ok() definition Message-ID: <20220214200011.GA3786@lst.de> References: <20220214163452.1568807-1-arnd@kernel.org> <20220214163452.1568807-5-arnd@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220214_120021_449086_4CBF2F5B X-CRM114-Status: GOOD ( 20.59 ) X-BeenThere: linux-snps-arc@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Linux on Synopsys ARC Processors List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-snps-arc" Errors-To: linux-snps-arc-bounces+linux-snps-arc=archiver.kernel.org@lists.infradead.org On Mon, Feb 14, 2022 at 08:45:52PM +0100, Arnd Bergmann wrote: > As Al pointed out, they turned out to be necessary on sparc64, but the only > definitions are on sparc64 and x86, so it's possible that they serve a similar > purpose here, in which case changing the limit from TASK_SIZE to > TASK_SIZE_MAX is probably wrong as well. > > So either I need to revert the original definition as I did on sparc64, or > they can be removed completely. Hopefully Al or the x86 maintainers > can clarify. Looking at the x86 users I think: - valid_user_frame should go away and the caller should use get_user instead of __get_user - the one in copy_code can just go away, as there is another check in copy_from_user_nmi - copy_stack_frame should just use access_ok - as does copy_from_user_nmi but yes, having someone who actually knows this code look over it would be very helpful. _______________________________________________ linux-snps-arc mailing list linux-snps-arc@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-snps-arc From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christoph Hellwig Date: Mon, 14 Feb 2022 21:00:11 +0100 Subject: [OpenRISC] [PATCH 04/14] x86: use more conventional access_ok() definition In-Reply-To: References: <20220214163452.1568807-1-arnd@kernel.org> <20220214163452.1568807-5-arnd@kernel.org> Message-ID: <20220214200011.GA3786@lst.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: openrisc@lists.librecores.org On Mon, Feb 14, 2022 at 08:45:52PM +0100, Arnd Bergmann wrote: > As Al pointed out, they turned out to be necessary on sparc64, but the only > definitions are on sparc64 and x86, so it's possible that they serve a similar > purpose here, in which case changing the limit from TASK_SIZE to > TASK_SIZE_MAX is probably wrong as well. > > So either I need to revert the original definition as I did on sparc64, or > they can be removed completely. Hopefully Al or the x86 maintainers > can clarify. Looking at the x86 users I think: - valid_user_frame should go away and the caller should use get_user instead of __get_user - the one in copy_code can just go away, as there is another check in copy_from_user_nmi - copy_stack_frame should just use access_ok - as does copy_from_user_nmi but yes, having someone who actually knows this code look over it would be very helpful. 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 Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D62DCC433F5 for ; Mon, 14 Feb 2022 20:00:52 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4JyFTH0b0Xz3cYg for ; Tue, 15 Feb 2022 07:00:51 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lst.de (client-ip=213.95.11.211; helo=verein.lst.de; envelope-from=hch@lst.de; receiver=) Received: from verein.lst.de (verein.lst.de [213.95.11.211]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4JyFSk5y44z2yLP for ; Tue, 15 Feb 2022 07:00:21 +1100 (AEDT) Received: by verein.lst.de (Postfix, from userid 2407) id 2A25C68AA6; Mon, 14 Feb 2022 21:00:11 +0100 (CET) Date: Mon, 14 Feb 2022 21:00:11 +0100 From: Christoph Hellwig To: Arnd Bergmann Subject: Re: [PATCH 04/14] x86: use more conventional access_ok() definition Message-ID: <20220214200011.GA3786@lst.de> References: <20220214163452.1568807-1-arnd@kernel.org> <20220214163452.1568807-5-arnd@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Rich Felker , linux-ia64@vger.kernel.org, Linux-sh list , Peter Zijlstra , "open list:BROADCOM NVRAM DRIVER" , Max Filippov , Guo Ren , sparclinux , linux-riscv , Will Deacon , Ard Biesheuvel , linux-arch , linux-s390 , Brian Cain , "open list:QUALCOMM HEXAGON..." , Helge Deller , the arch/x86 maintainers , Russell King - ARM Linux , linux-csky@vger.kernel.org, Christoph Hellwig , Christoph Hellwig , Ingo Molnar , Geert Uytterhoeven , "open list:SYNOPSYS ARC ARCHITECTURE" , "open list:TENSILICA XTENSA PORT \(xtensa\)" , Arnd Bergmann , Heiko Carstens , linux-um , linuxppc-dev , Richard Weinberger , linux-m68k , Openrisc , Greentime Hu , Stafford Horne , Linux ARM , Michal Simek , Thomas Bogendoerfer , Nick Hu , Parisc List , Linux-MM , Linux API , Linux Kernel Mailing List , Dinh Nguyen , "Eric W . Biederman" , alpha , Andrew Morton , Linus Torvalds , David Miller , Al Viro Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Mon, Feb 14, 2022 at 08:45:52PM +0100, Arnd Bergmann wrote: > As Al pointed out, they turned out to be necessary on sparc64, but the only > definitions are on sparc64 and x86, so it's possible that they serve a similar > purpose here, in which case changing the limit from TASK_SIZE to > TASK_SIZE_MAX is probably wrong as well. > > So either I need to revert the original definition as I did on sparc64, or > they can be removed completely. Hopefully Al or the x86 maintainers > can clarify. Looking at the x86 users I think: - valid_user_frame should go away and the caller should use get_user instead of __get_user - the one in copy_code can just go away, as there is another check in copy_from_user_nmi - copy_stack_frame should just use access_ok - as does copy_from_user_nmi but yes, having someone who actually knows this code look over it would be very helpful.