From patchwork Fri Apr 23 13:16:39 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Hildenbrand X-Patchwork-Id: 12220379 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=-15.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 B5471C43461 for ; Fri, 23 Apr 2021 13:19:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7FD3A6144A for ; Fri, 23 Apr 2021 13:19:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242722AbhDWNTh (ORCPT ); Fri, 23 Apr 2021 09:19:37 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:45552 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230521AbhDWNTg (ORCPT ); Fri, 23 Apr 2021 09:19:36 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1619183940; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=G+eWfvvqRHIQo50NRHl9uKd40XC8OMEOCd7Vn2cTNYY=; b=YSK0q6091Jky9jM+XjvOdnNVDcrEmNJCcBxFQYKOyesun7F9L5QjFh0YXmONjzmHT+LrTG rDf0vsgsQRbqm8VXiTdWmepKQokl84qXsu46crDrG7qHx/iqx0PPPMwtOcOvlMeh9LAIkk c3ANETIPULtnfB2PxfcrE5DnsApPX7Q= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-517-GRZO6q5fN56xrlOboa2Hjg-1; Fri, 23 Apr 2021 09:18:55 -0400 X-MC-Unique: GRZO6q5fN56xrlOboa2Hjg-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 12D2C107ACED; Fri, 23 Apr 2021 13:18:47 +0000 (UTC) Received: from t480s.redhat.com (ovpn-112-41.ams2.redhat.com [10.36.112.41]) by smtp.corp.redhat.com (Postfix) with ESMTP id 58DA160BE5; Fri, 23 Apr 2021 13:18:26 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: David Hildenbrand , Andrew Morton , Thomas Gleixner , Ingo Molnar , Borislav Petkov , "H. Peter Anvin" , Alexander Viro , Alexey Dobriyan , Steven Rostedt , Peter Zijlstra , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Petr Mladek , Sergey Senozhatsky , Andy Shevchenko , Rasmus Villemoes , Kees Cook , "Eric W. Biederman" , Greg Ungerer , Geert Uytterhoeven , Mike Rapoport , Vlastimil Babka , Vincenzo Frascino , Chinwen Chang , Michel Lespinasse , Catalin Marinas , "Matthew Wilcox (Oracle)" , Huang Ying , Jann Horn , Feng Tang , Kevin Brodsky , Michael Ellerman , Shawn Anastasio , Steven Price , Nicholas Piggin , Christian Brauner , Jens Axboe , Gabriel Krisman Bertazi , Peter Xu , Suren Baghdasaryan , Shakeel Butt , Marco Elver , Daniel Jordan , Nicolas Viennot , Thomas Cedeno , Collin Fijalkovich , Michal Hocko , linux-api@vger.kernel.org, x86@kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH RFC 6/7] mm: ignore MAP_DENYWRITE in ksys_mmap_pgoff() Date: Fri, 23 Apr 2021 15:16:39 +0200 Message-Id: <20210423131640.20080-7-david@redhat.com> In-Reply-To: <20210423131640.20080-1-david@redhat.com> References: <20210423131640.20080-1-david@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Let's also remove masking off MAP_DENYWROTE from ksys_mmap_pgoff(): the last in-tree occurrence of MAP_DENYWRITE is now in LEGACY_MAP_MASK, which accepts the flag e.g., for MAP_SHARED_VALIDATE; however, the flag is ignored throughout the kernel now. Add a comment to LEGACY_MAP_MASK stating that MAP_DENYWRITE is ignored. Signed-off-by: David Hildenbrand --- include/linux/mman.h | 3 ++- mm/mmap.c | 2 -- mm/nommu.c | 2 -- 3 files changed, 2 insertions(+), 5 deletions(-) diff --git a/include/linux/mman.h b/include/linux/mman.h index bd9aadda047b..b66e91b8176c 100644 --- a/include/linux/mman.h +++ b/include/linux/mman.h @@ -32,7 +32,8 @@ * The historical set of flags that all mmap implementations implicitly * support when a ->mmap_validate() op is not provided in file_operations. * - * MAP_EXECUTABLE is completely ignored throughout the kernel. + * MAP_EXECUTABLE and MAP_DENYWRITE are completely ignored throughout the + * kernel. */ #define LEGACY_MAP_MASK (MAP_SHARED \ | MAP_PRIVATE \ diff --git a/mm/mmap.c b/mm/mmap.c index b335f8907568..33479ce05653 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1623,8 +1623,6 @@ unsigned long ksys_mmap_pgoff(unsigned long addr, unsigned long len, return PTR_ERR(file); } - flags &= ~MAP_DENYWRITE; - retval = vm_mmap_pgoff(file, addr, len, prot, flags, pgoff); out_fput: if (file) diff --git a/mm/nommu.c b/mm/nommu.c index 1fafe3e9d3df..7d85c8a46582 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -1306,8 +1306,6 @@ unsigned long ksys_mmap_pgoff(unsigned long addr, unsigned long len, goto out; } - flags &= ~MAP_DENYWRITE; - retval = vm_mmap_pgoff(file, addr, len, prot, flags, pgoff); if (file)