From patchwork Thu Apr 1 22:10:50 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu-cheng Yu X-Patchwork-Id: 12179687 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,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 06D99C43618 for ; Thu, 1 Apr 2021 22:11:53 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 79C33610FA for ; Thu, 1 Apr 2021 22:11:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 79C33610FA Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id D53B66B00ED; Thu, 1 Apr 2021 18:11:28 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id CAA266B00F4; Thu, 1 Apr 2021 18:11:28 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 9E4D16B00F5; Thu, 1 Apr 2021 18:11:28 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0090.hostedemail.com [216.40.44.90]) by kanga.kvack.org (Postfix) with ESMTP id 7A4706B00F0 for ; Thu, 1 Apr 2021 18:11:28 -0400 (EDT) Received: from smtpin02.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 4A99B1839A9C7 for ; Thu, 1 Apr 2021 22:11:28 +0000 (UTC) X-FDA: 77985195456.02.3FC5EB7 Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by imf19.hostedemail.com (Postfix) with ESMTP id 5F84190009E2 for ; Thu, 1 Apr 2021 22:11:25 +0000 (UTC) IronPort-SDR: MSfKg87AcsJYGlOW2QMegKYFnCvenw7zeaCvOh8Z5EsfOmXH04kBaSLuTG9YdHah0j5IS6J4Mr wXTU1gTc3Xxg== X-IronPort-AV: E=McAfee;i="6000,8403,9941"; a="192371369" X-IronPort-AV: E=Sophos;i="5.81,296,1610438400"; d="scan'208";a="192371369" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Apr 2021 15:11:24 -0700 IronPort-SDR: mpWU7ZRZ10LDWKSod+5CSr0sTZSexKKRE2GvtO5cH2swVdThcqVjhzlRY2XkNJWjgaeqv6nbN3 SXU97KX1bJ/w== X-IronPort-AV: E=Sophos;i="5.81,296,1610438400"; d="scan'208";a="517513915" Received: from yyu32-desk.sc.intel.com ([143.183.136.146]) by fmsmga001-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 01 Apr 2021 15:11:24 -0700 From: Yu-cheng Yu To: x86@kernel.org, "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, Arnd Bergmann , Andy Lutomirski , Balbir Singh , Borislav Petkov , Cyrill Gorcunov , Dave Hansen , Eugene Syromiatnikov , Florian Weimer , "H.J. Lu" , Jann Horn , Jonathan Corbet , Kees Cook , Mike Kravetz , Nadav Amit , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , "Ravi V. Shankar" , Vedvyas Shanbhogue , Dave Martin , Weijiang Yang , Pengfei Xu , Haitao Huang Cc: Yu-cheng Yu , "Kirill A . Shutemov" Subject: [PATCH v24 16/30] mm: Fixup places that call pte_mkwrite() directly Date: Thu, 1 Apr 2021 15:10:50 -0700 Message-Id: <20210401221104.31584-17-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20210401221104.31584-1-yu-cheng.yu@intel.com> References: <20210401221104.31584-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 X-Rspamd-Queue-Id: 5F84190009E2 X-Stat-Signature: 4ui8hjhq5k6u9mus7qixh6rga8xx4xrm X-Rspamd-Server: rspam02 Received-SPF: none (intel.com>: No applicable sender policy available) receiver=imf19; identity=mailfrom; envelope-from=""; helo=mga03.intel.com; client-ip=134.134.136.65 X-HE-DKIM-Result: none/none X-HE-Tag: 1617315085-78887 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: When serving a page fault, maybe_mkwrite() makes a PTE writable if it is in a writable vma. A shadow stack vma is writable, but its PTEs need _PAGE_DIRTY to be set to become writable. For this reason, maybe_mkwrite() has been updated. There are a few places that call pte_mkwrite() directly, but have the same result as from maybe_mkwrite(). These sites need to be updated for shadow stack as well. Thus, change them to maybe_mkwrite(): - do_anonymous_page() and migrate_vma_insert_page() check VM_WRITE directly and call pte_mkwrite(), which is the same as maybe_mkwrite(). Change them to maybe_mkwrite(). - In do_numa_page(), if the numa entry was writable, then pte_mkwrite() is called directly. Fix it by doing maybe_mkwrite(). - In change_pte_range(), pte_mkwrite() is called directly. Replace it with maybe_mkwrite(). A shadow stack vma is writable but has different vma flags, and handled accordingly in maybe_mkwrite(). Signed-off-by: Yu-cheng Yu Reviewed-by: Kees Cook Cc: Kirill A. Shutemov --- mm/memory.c | 5 ++--- mm/migrate.c | 3 +-- mm/mprotect.c | 2 +- 3 files changed, 4 insertions(+), 6 deletions(-) diff --git a/mm/memory.c b/mm/memory.c index 5efa07fb6cdc..c70c3847f79d 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3561,8 +3561,7 @@ static vm_fault_t do_anonymous_page(struct vm_fault *vmf) __SetPageUptodate(page); entry = mk_pte(page, vma->vm_page_prot); - if (vma->vm_flags & VM_WRITE) - entry = pte_mkwrite(pte_mkdirty(entry)); + entry = maybe_mkwrite(pte_mkdirty(entry), vma); vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd, vmf->address, &vmf->ptl); @@ -4125,7 +4124,7 @@ static vm_fault_t do_numa_page(struct vm_fault *vmf) pte = pte_modify(old_pte, vma->vm_page_prot); pte = pte_mkyoung(pte); if (was_writable) - pte = pte_mkwrite(pte); + pte = maybe_mkwrite(pte, vma); ptep_modify_prot_commit(vma, vmf->address, vmf->pte, old_pte, pte); update_mmu_cache(vma, vmf->address, vmf->pte); diff --git a/mm/migrate.c b/mm/migrate.c index 62b81d5257aa..7251c88a3d64 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -2976,8 +2976,7 @@ static void migrate_vma_insert_page(struct migrate_vma *migrate, } } else { entry = mk_pte(page, vma->vm_page_prot); - if (vma->vm_flags & VM_WRITE) - entry = pte_mkwrite(pte_mkdirty(entry)); + entry = maybe_mkwrite(pte_mkdirty(entry), vma); } ptep = pte_offset_map_lock(mm, pmdp, addr, &ptl); diff --git a/mm/mprotect.c b/mm/mprotect.c index 94188df1ee55..c1ce78d688b6 100644 --- a/mm/mprotect.c +++ b/mm/mprotect.c @@ -135,7 +135,7 @@ static unsigned long change_pte_range(struct vm_area_struct *vma, pmd_t *pmd, if (dirty_accountable && pte_dirty(ptent) && (pte_soft_dirty(ptent) || !(vma->vm_flags & VM_SOFTDIRTY))) { - ptent = pte_mkwrite(ptent); + ptent = maybe_mkwrite(ptent, vma); } ptep_modify_prot_commit(vma, addr, pte, oldpte, ptent); pages++;