From patchwork Fri Sep 4 10:30:15 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Catalin Marinas X-Patchwork-Id: 11756539 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BC34E91F for ; Fri, 4 Sep 2020 10:31:13 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 8EA7521481 for ; Fri, 4 Sep 2020 10:31:13 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8EA7521481 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 7FEE06B0095; Fri, 4 Sep 2020 06:31:11 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 75F956B0096; Fri, 4 Sep 2020 06:31:11 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5D86B6B0098; Fri, 4 Sep 2020 06:31:11 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0219.hostedemail.com [216.40.44.219]) by kanga.kvack.org (Postfix) with ESMTP id 4264E6B0095 for ; Fri, 4 Sep 2020 06:31:11 -0400 (EDT) Received: from smtpin25.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 03AEB824556B for ; Fri, 4 Sep 2020 10:31:11 +0000 (UTC) X-FDA: 77225011542.25.coal17_2f0c1ac270b1 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin25.hostedemail.com (Postfix) with ESMTP id C2FF31804E3A1 for ; Fri, 4 Sep 2020 10:31:10 +0000 (UTC) X-Spam-Summary: 1,0,0,c900458b281550cb,d41d8cd98f00b204,cmainas@kernel.org,,RULES_HIT:41:355:379:541:800:960:966:973:988:989:1260:1311:1314:1345:1359:1431:1437:1515:1534:1542:1711:1730:1747:1777:1792:2196:2199:2393:2553:2559:2562:2895:2914:3138:3139:3140:3141:3142:3353:3865:3867:3868:3870:3871:3872:4321:4385:4605:5007:6261:7875:10004:11026:11232:11658:11914:12043:12114:12296:12297:12438:12517:12519:12555:12986:13180:13229:13894:14096:14181:14394:14721:21080:21230:21451:21627:21990:30012:30054:30090,0,RBL:198.145.29.99:@kernel.org:.lbl8.mailshell.net-64.100.201.201 62.2.0.100;04yrq9xbynk3y3m591zxqkf7493phycwxs8oogya15eut9tofxtpmuc9c6gewu7.swkhhkypd3x9qp6nohg1eznbgozxhucyhxmt7b44cg565zzxy36awf3e6ygzc8a.s-lbl8.mailshell.net-223.238.255.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:23,LUA_SUMMARY:none X-HE-Tag: coal17_2f0c1ac270b1 X-Filterd-Recvd-Size: 3742 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf05.hostedemail.com (Postfix) with ESMTP for ; Fri, 4 Sep 2020 10:31:10 +0000 (UTC) Received: from localhost.localdomain (unknown [46.69.195.48]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 88B412084D; Fri, 4 Sep 2020 10:31:07 +0000 (UTC) From: Catalin Marinas To: linux-arm-kernel@lists.infradead.org Cc: linux-mm@kvack.org, linux-arch@vger.kernel.org, Will Deacon , Dave P Martin , Vincenzo Frascino , Szabolcs Nagy , Kevin Brodsky , Andrey Konovalov , Peter Collingbourne , Andrew Morton Subject: [PATCH v9 15/29] mm: Introduce arch_validate_flags() Date: Fri, 4 Sep 2020 11:30:15 +0100 Message-Id: <20200904103029.32083-16-catalin.marinas@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200904103029.32083-1-catalin.marinas@arm.com> References: <20200904103029.32083-1-catalin.marinas@arm.com> MIME-Version: 1.0 X-Rspamd-Queue-Id: C2FF31804E3A1 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam03 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Similarly to arch_validate_prot() called from do_mprotect_pkey(), an architecture may need to sanity-check the new vm_flags. Define a dummy function always returning true. In addition to do_mprotect_pkey(), also invoke it from mmap_region() prior to updating vma->vm_page_prot to allow the architecture code to veto potentially inconsistent vm_flags. Signed-off-by: Catalin Marinas Acked-by: Andrew Morton --- Notes: v2: - Some comments updated. include/linux/mman.h | 13 +++++++++++++ mm/mmap.c | 9 +++++++++ mm/mprotect.c | 6 ++++++ 3 files changed, 28 insertions(+) diff --git a/include/linux/mman.h b/include/linux/mman.h index 6fa15c9b12af..629cefc4ecba 100644 --- a/include/linux/mman.h +++ b/include/linux/mman.h @@ -108,6 +108,19 @@ static inline bool arch_validate_prot(unsigned long prot, unsigned long addr) #define arch_validate_prot arch_validate_prot #endif +#ifndef arch_validate_flags +/* + * This is called from mmap() and mprotect() with the updated vma->vm_flags. + * + * Returns true if the VM_* flags are valid. + */ +static inline bool arch_validate_flags(unsigned long flags) +{ + return true; +} +#define arch_validate_flags arch_validate_flags +#endif + /* * Optimisation macro. It is equivalent to: * (x & bit1) ? bit2 : 0 diff --git a/mm/mmap.c b/mm/mmap.c index 40248d84ad5f..eed30b096667 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1812,6 +1812,15 @@ unsigned long mmap_region(struct file *file, unsigned long addr, vma_set_anonymous(vma); } + /* Allow architectures to sanity-check the vm_flags */ + if (!arch_validate_flags(vma->vm_flags)) { + error = -EINVAL; + if (file) + goto unmap_and_free_vma; + else + goto free_vma; + } + vma_link(mm, vma, prev, rb_link, rb_parent); /* Once vma denies write, undo our temporary denial count */ if (file) { diff --git a/mm/mprotect.c b/mm/mprotect.c index ce8b8a5eacbb..56c02beb6041 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -603,6 +603,12 @@ static int do_mprotect_pkey(unsigned long start, size_t len, goto out; } + /* Allow architectures to sanity-check the new flags */ + if (!arch_validate_flags(newflags)) { + error = -EINVAL; + goto out; + } + error = security_file_mprotect(vma, reqprot, prot); if (error) goto out;