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=-0.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 EB754C433EC for ; Wed, 27 May 2020 15:31:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CB9F420C09 for ; Wed, 27 May 2020 15:31:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590593498; bh=FYlTjZDDWzv75K1cm++7jCZ9U5TmYAzARky7QAXahI0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=mYZTrAR7yBIDe+nTtm+z7vjmBV+T+zHC6mYHJ/3fI24zZLAndN7CSZxOJJ2aupRAw gssYg6IpToy+G747dsJxASKNLzpXQoS2ze7zbMTgzh7Imwdy7S61f6HPyDmLUASihY kXnYH+0GQ/x40iW5Ux++BidaYANwLTKILw2BnxhM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728753AbgE0Pbi (ORCPT ); Wed, 27 May 2020 11:31:38 -0400 Received: from mail.kernel.org ([198.145.29.99]:43968 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728829AbgE0Pbd (ORCPT ); Wed, 27 May 2020 11:31:33 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3CA63208E4; Wed, 27 May 2020 15:31:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590593492; bh=FYlTjZDDWzv75K1cm++7jCZ9U5TmYAzARky7QAXahI0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=jXXSlSss9GQcJwOVQ18QpEkpPQ0UHggQ0gnw7GFrNNzCuPWE5+rTO8d+c6uVeB6Cs 78bnb0WIkRzmYIS3AQo7EY1dOw9IStfAv5KBXtOZEmWdm4DU6tsewCwDtPxhwIJtUo seapiYMExTH/ZC9Us+4q6KTSv6ZC6Zm+15xcQP3E= Date: Wed, 27 May 2020 17:31:30 +0200 From: Greg KH To: Ashwin H Cc: "x86@kernel.org" , "dri-devel@lists.freedesktop.org" , "intel-gfx@lists.freedesktop.org" , "linux-kernel@vger.kernel.org" , "stable@kernel.org" , Srivatsa Bhat , "srivatsa@csail.mit.edu" , "rostedt@goodmis.org" , Steven Rostedt , Linus Torvalds Subject: Re: [PATCH v4.19.x] make 'user_access_begin()' do 'access_ok()' Message-ID: <20200527153130.GA525531@kroah.com> References: <20200513055548.GA743118@kroah.com> <89DE19F6-4CB0-4324-A630-C8574C8D591C@vmware.com> <20200513063455.GA752913@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 13, 2020 at 05:08:19PM +0000, Ashwin H wrote: > > Ok, but what does that mean for us? > > > > You need to say why you are sending a patch, otherwise we will guess wrong. > > In drivers/gpu/drm/i915/i915_gem_execbuffer.c, ioctl functions does user_access_begin() without doing access_ok(Checks if a user space pointer is valid) first. > A local attacker can craft a malicious ioctl function call to overwrite arbitrary kernel memory, resulting in a Denial of Service or privilege escalation (CVE-2018-20669) > > This patch makes sure that user_access_begin always does access_ok. > user_access_begin has been modified to do access_ok internally. I had this in the tree, but it broke the build on alpha, sh, and maybe a few others :( See: https://lore.kernel.org/r/20200527140225.GA214763@roeck-us.net for the details. Can you dig out all of the needed follow-on patches as well, and send them all as a patch series for 4.19.y so that I can queue them all up at once? thanks, greg k-h