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 B8B29C433E0 for ; Wed, 10 Feb 2021 17:58:35 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 4DC1064EDA for ; Wed, 10 Feb 2021 17:58:35 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4DC1064EDA 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 4A5F48D0007; Wed, 10 Feb 2021 12:58:10 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 194828D0006; Wed, 10 Feb 2021 12:58:10 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E8ED78D0008; Wed, 10 Feb 2021 12:58:09 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0002.hostedemail.com [216.40.44.2]) by kanga.kvack.org (Postfix) with ESMTP id AE6958D0003 for ; Wed, 10 Feb 2021 12:58:09 -0500 (EST) Received: from smtpin08.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 7E07A824556B for ; Wed, 10 Feb 2021 17:58:09 +0000 (UTC) X-FDA: 77803117098.08.color93_2305d2927611 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin08.hostedemail.com (Postfix) with ESMTP id 635C31819E63D for ; Wed, 10 Feb 2021 17:58:09 +0000 (UTC) X-HE-Tag: color93_2305d2927611 X-Filterd-Recvd-Size: 5663 Received: from mga06.intel.com (mga06.intel.com [134.134.136.31]) by imf43.hostedemail.com (Postfix) with ESMTP for ; Wed, 10 Feb 2021 17:58:08 +0000 (UTC) IronPort-SDR: BMk1I/HTL5HkcIQeqOWbudS86N+WzlqZ/okWYSbmpZ9KMRQK8YkMMUcjV1/HXJfoxKn4fWV7D1 TqdCPW70EgYw== X-IronPort-AV: E=McAfee;i="6000,8403,9891"; a="243612384" X-IronPort-AV: E=Sophos;i="5.81,168,1610438400"; d="scan'208";a="243612384" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Feb 2021 09:58:02 -0800 IronPort-SDR: ZW/iM+50AstOVrPoiDceubfpVdDY39Xp0gEO69RXcVuR+5iawfiPkvmkFCR2630lu/AwFHSqil mRZGASGTIRug== X-IronPort-AV: E=Sophos;i="5.81,168,1610438400"; d="scan'208";a="421140769" Received: from yyu32-desk.sc.intel.com ([143.183.136.146]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Feb 2021 09:58:02 -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 , Cc: Yu-cheng Yu Subject: [PATCH v20 15/25] mm: Fixup places that call pte_mkwrite() directly Date: Wed, 10 Feb 2021 09:56:53 -0800 Message-Id: <20210210175703.12492-16-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20210210175703.12492-1-yu-cheng.yu@intel.com> References: <20210210175703.12492-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 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 feff48e1465a..1de649c61013 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3549,8 +3549,7 @@ static vm_fault_t do_anonymous_page(struct vm_fault= *vmf) =20 entry =3D mk_pte(page, vma->vm_page_prot); entry =3D pte_sw_mkyoung(entry); - 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); @@ -4205,7 +4204,7 @@ 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 20ca887ea769..5c6b1a4c25a2 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -2970,8 +2970,7 @@ 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 ab709023e9aa..ed26e675c423 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