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=-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 D6BF9C433E0 for ; Wed, 10 Mar 2021 22:01:51 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 8582564E27 for ; Wed, 10 Mar 2021 22:01:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8582564E27 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 C098D8D0226; Wed, 10 Mar 2021 17:01:22 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id B11D18D0229; Wed, 10 Mar 2021 17:01:22 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7FF1D8D0226; Wed, 10 Mar 2021 17:01:22 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0053.hostedemail.com [216.40.44.53]) by kanga.kvack.org (Postfix) with ESMTP id 570778D0227 for ; Wed, 10 Mar 2021 17:01:22 -0500 (EST) Received: from smtpin24.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 1A7C03AA1 for ; Wed, 10 Mar 2021 22:01:22 +0000 (UTC) X-FDA: 77905336404.24.6D493DD Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by imf12.hostedemail.com (Postfix) with ESMTP id 8EC4DF9 for ; Wed, 10 Mar 2021 22:01:17 +0000 (UTC) IronPort-SDR: KUDjvKXhyQQPQnDf9OYHpCe4178UMhdu40HWEXn53ccnXaSTCsyl3ja7cOQf9B5QoYYUUtSI1f 0vw6M7W7XOMg== X-IronPort-AV: E=McAfee;i="6000,8403,9919"; a="167846449" X-IronPort-AV: E=Sophos;i="5.81,238,1610438400"; d="scan'208";a="167846449" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Mar 2021 14:01:16 -0800 IronPort-SDR: 0VP7qFxdbDCEGishuntCBq3tSyrUnhC8YPyo3wCp+hIjhHAkzT07599rqPCWCVeh/AiB2o9F5f qZNci/aEbpEA== X-IronPort-AV: E=Sophos;i="5.81,238,1610438400"; d="scan'208";a="403847628" Received: from yyu32-desk.sc.intel.com ([143.183.136.146]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Mar 2021 14:01:16 -0800 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 Subject: [PATCH v22 16/28] mm: Fixup places that call pte_mkwrite() directly Date: Wed, 10 Mar 2021 14:00:34 -0800 Message-Id: <20210310220046.15866-17-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20210310220046.15866-1-yu-cheng.yu@intel.com> References: <20210310220046.15866-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 8EC4DF9 X-Stat-Signature: e1sb7hd4rnc8b43cr8xy49gbuoobrj7g Received-SPF: none (intel.com>: No applicable sender policy available) receiver=imf12; identity=mailfrom; envelope-from=""; helo=mga12.intel.com; client-ip=192.55.52.136 X-HE-DKIM-Result: none/none X-HE-Tag: 1615413677-784484 Content-Transfer-Encoding: quoted-printable 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 effect 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 direct= ly 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 wi= th 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 --- 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 c8e357627318..0bdc6f2a8fe0 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3559,8 +3559,7 @@ static vm_fault_t do_anonymous_page(struct vm_fault= *vmf) __SetPageUptodate(page); =20 entry =3D mk_pte(page, vma->vm_page_prot); - if (vma->vm_flags & VM_WRITE) - entry =3D pte_mkwrite(pte_mkdirty(entry)); + entry =3D maybe_mkwrite(pte_mkdirty(entry), vma); =20 vmf->pte =3D pte_offset_map_lock(vma->vm_mm, vmf->pmd, vmf->address, &vmf->ptl); @@ -4123,7 +4122,7 @@ static vm_fault_t do_numa_page(struct vm_fault *vmf= ) pte =3D pte_modify(old_pte, vma->vm_page_prot); pte =3D pte_mkyoung(pte); if (was_writable) - pte =3D pte_mkwrite(pte); + pte =3D maybe_mkwrite(pte, vma); ptep_modify_prot_commit(vma, vmf->address, vmf->pte, old_pte, pte); update_mmu_cache(vma, vmf->address, vmf->pte); =20 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 =3D mk_pte(page, vma->vm_page_prot); - if (vma->vm_flags & VM_WRITE) - entry =3D pte_mkwrite(pte_mkdirty(entry)); + entry =3D maybe_mkwrite(pte_mkdirty(entry), vma); } =20 ptep =3D 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 =3D pte_mkwrite(ptent); + ptent =3D maybe_mkwrite(ptent, vma); } ptep_modify_prot_commit(vma, addr, pte, oldpte, ptent); pages++; --=20 2.21.0