From patchwork Wed Feb 17 22:27:19 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: 12092529 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=-16.7 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 2653CC433DB for ; Wed, 17 Feb 2021 22:28:34 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id CF27061494 for ; Wed, 17 Feb 2021 22:28:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CF27061494 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 433718D000A; Wed, 17 Feb 2021 17:28:05 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 297BD8D000D; Wed, 17 Feb 2021 17:28:05 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id EC22A8D0009; Wed, 17 Feb 2021 17:28:04 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0182.hostedemail.com [216.40.44.182]) by kanga.kvack.org (Postfix) with ESMTP id C658F8D000A for ; Wed, 17 Feb 2021 17:28:04 -0500 (EST) Received: from smtpin22.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 93488181AC1E9 for ; Wed, 17 Feb 2021 22:28:04 +0000 (UTC) X-FDA: 77829198888.22.ant02_2e0f69a27650 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin22.hostedemail.com (Postfix) with ESMTP id 7560118038E60 for ; Wed, 17 Feb 2021 22:28:04 +0000 (UTC) X-HE-Tag: ant02_2e0f69a27650 X-Filterd-Recvd-Size: 5676 Received: from mga18.intel.com (mga18.intel.com [134.134.136.126]) by imf40.hostedemail.com (Postfix) with ESMTP for ; Wed, 17 Feb 2021 22:28:03 +0000 (UTC) IronPort-SDR: uQLHMXtsMR5lhPck6+7l5nKJmt0hDSGezpS2tq5yV6kRzbR2sVb88AeOiJ0jurlvv9Vi3OjgoC WXftpuSHOaRw== X-IronPort-AV: E=McAfee;i="6000,8403,9898"; a="170994037" X-IronPort-AV: E=Sophos;i="5.81,185,1610438400"; d="scan'208";a="170994037" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Feb 2021 14:28:02 -0800 IronPort-SDR: tYEMB7Wzg6Ee5INOF0eoajY72uqdDNrvL0X7JDTfLa6nOobALr72XOic7wyFicXA3DKu8l8CWd 5vg3tFgp7dPA== X-IronPort-AV: E=Sophos;i="5.81,185,1610438400"; d="scan'208";a="400172648" Received: from yyu32-desk.sc.intel.com ([143.183.136.146]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Feb 2021 14:28:01 -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 v21 15/26] mm: Fixup places that call pte_mkwrite() directly Date: Wed, 17 Feb 2021 14:27:19 -0800 Message-Id: <20210217222730.15819-16-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20210217222730.15819-1-yu-cheng.yu@intel.com> References: <20210217222730.15819-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 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 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 --- 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) entry = mk_pte(page, vma->vm_page_prot); entry = pte_sw_mkyoung(entry); - 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); @@ -4205,7 +4204,7 @@ 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 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 = 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 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 = pte_mkwrite(ptent); + ptent = maybe_mkwrite(ptent, vma); } ptep_modify_prot_commit(vma, addr, pte, oldpte, ptent); pages++;