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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4A1F3C433FE for ; Mon, 3 Oct 2022 18:10:06 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 835928E0001; Mon, 3 Oct 2022 14:10:05 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 7E59D6B0073; Mon, 3 Oct 2022 14:10:05 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 686918E0001; Mon, 3 Oct 2022 14:10:05 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 534266B0071 for ; Mon, 3 Oct 2022 14:10:05 -0400 (EDT) Received: from smtpin10.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id F01A41A0968 for ; Mon, 3 Oct 2022 18:10:04 +0000 (UTC) X-FDA: 79980427128.10.C37B6D6 Received: from mga18.intel.com (mga18.intel.com [134.134.136.126]) by imf03.hostedemail.com (Postfix) with ESMTP id 49E4420009 for ; Mon, 3 Oct 2022 18:10:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1664820604; x=1696356604; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=32i7PipZSw6KqH6MkU9eJfthXyxPQbhK8WM6mxd9tBw=; b=PebN+pOGcCESHNPAak9vEwS6fdlsk4xueI9Ir/GLRww2C2EWs234yhLq GHMw/NfaOvIxedlFsmxX+3V+6U2Tcc9ekW6VZ+Ec6pRbb4N98zcoFckTf IPgiJxlzjrit+0kOag6EZJli/VFuc0EGTC5mKayOL/yviUj7TQtlk4cLp eDBFFszB/cZuD6Jfjymozh2OfcutQUyzgXTIWf/I4+keCY0Z4pQi7vcfm yOCNh4gW7dE+iDmRNpnlKSSnU+5Se+pvEVAEO2jW8vYGrpn37/ff2Pik9 G7+pTrnLFrSH0dNBAUyforkQ0daHHkOB1KJ17GyfBQP7+S6zkBULqQV0O A==; X-IronPort-AV: E=McAfee;i="6500,9779,10489"; a="285890507" X-IronPort-AV: E=Sophos;i="5.93,366,1654585200"; d="scan'208";a="285890507" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Oct 2022 10:47:42 -0700 X-IronPort-AV: E=McAfee;i="6500,9779,10489"; a="601318407" X-IronPort-AV: E=Sophos;i="5.93,366,1654585200"; d="scan'208";a="601318407" Received: from bandrei-mobl.ger.corp.intel.com (HELO box.shutemov.name) ([10.252.37.219]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Oct 2022 10:47:31 -0700 Received: by box.shutemov.name (Postfix, from userid 1000) id 6BB78104CE4; Mon, 3 Oct 2022 20:47:27 +0300 (+03) Date: Mon, 3 Oct 2022 20:47:27 +0300 From: "Kirill A . Shutemov" To: Rick Edgecombe Cc: 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" , Weijiang Yang , joao.moreira@intel.com, John Allen , kcc@google.com, eranian@google.com, rppt@kernel.org, jamorris@linux.microsoft.com, dethoma@microsoft.com, Yu-cheng Yu Subject: Re: [PATCH v2 14/39] mm: Introduce VM_SHADOW_STACK for shadow stack memory Message-ID: <20221003174727.vvposwdd4fmmi3hw@box.shutemov.name> References: <20220929222936.14584-1-rick.p.edgecombe@intel.com> <20220929222936.14584-15-rick.p.edgecombe@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220929222936.14584-15-rick.p.edgecombe@intel.com> ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1664820604; a=rsa-sha256; cv=none; b=ldW3V/qWjNX3XHdoIQyMKLIU57gUJfSjoxhSdjGBeGrhR5pdVOTX+6no3KqcW/JUwLWPmE /C32YZ+L3M7iqoBPRwAIi6wC8VKrOC8QcLMQsJV1YdD176MgL0+w0Nd8rU1AZvBzCcg5or KZe7h3LjcQQqSUn77Rwd06IBtDERZZM= ARC-Authentication-Results: i=1; imf03.hostedemail.com; dkim=none ("invalid DKIM record") header.d=intel.com header.s=Intel header.b=PebN+pOG; dmarc=fail reason="No valid SPF" header.from=intel.com (policy=none); spf=none (imf03.hostedemail.com: domain of kirill.shutemov@linux.intel.com has no SPF policy when checking 134.134.136.126) smtp.mailfrom=kirill.shutemov@linux.intel.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1664820604; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=dp/8lJEwENuZSJz/4RxsrHuD0PrSPHT5zIGtPqZSZko=; b=a6u0DSI/jVR/PDc20yMZ994fE8jfmHCGWgifVnCzIJxE6Hiygpe7PJK806OROmEvd5MknT BIOMg13pCd1QzZxdcKq0ShXwSxOj3HacCKLkNSTx1RlX4EFUILVLv+f7GRKNBvKVcAoQbh QyQi+lPWSD7cgbJNF/YADMqgBtBiWs4= X-Rspam-User: Authentication-Results: imf03.hostedemail.com; dkim=none ("invalid DKIM record") header.d=intel.com header.s=Intel header.b=PebN+pOG; dmarc=fail reason="No valid SPF" header.from=intel.com (policy=none); spf=none (imf03.hostedemail.com: domain of kirill.shutemov@linux.intel.com has no SPF policy when checking 134.134.136.126) smtp.mailfrom=kirill.shutemov@linux.intel.com X-Stat-Signature: 6rr7e5jnmj7gy4yp5cpidokkubcykaqn X-Rspamd-Queue-Id: 49E4420009 X-Rspamd-Server: rspam09 X-HE-Tag: 1664820604-190622 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: On Thu, Sep 29, 2022 at 03:29:11PM -0700, Rick Edgecombe wrote: > From: Yu-cheng Yu > > A shadow stack PTE must be read-only and have _PAGE_DIRTY set. However, > read-only and Dirty PTEs also exist for copy-on-write (COW) pages. These > two cases are handled differently for page faults. Introduce > VM_SHADOW_STACK to track shadow stack VMAs. > > Signed-off-by: Yu-cheng Yu > Reviewed-by: Kirill A. Shutemov > Signed-off-by: Rick Edgecombe > Cc: Kees Cook > --- > Documentation/filesystems/proc.rst | 1 + > arch/x86/mm/mmap.c | 2 ++ > fs/proc/task_mmu.c | 3 +++ > include/linux/mm.h | 8 ++++++++ > 4 files changed, 14 insertions(+) > > diff --git a/Documentation/filesystems/proc.rst b/Documentation/filesystems/proc.rst > index e7aafc82be99..d54ff397947a 100644 > --- a/Documentation/filesystems/proc.rst > +++ b/Documentation/filesystems/proc.rst > @@ -560,6 +560,7 @@ encoded manner. The codes are the following: > mt arm64 MTE allocation tags are enabled > um userfaultfd missing tracking > uw userfaultfd wr-protect tracking > + ss shadow stack page > == ======================================= > > Note that there is no guarantee that every flag and associated mnemonic will > diff --git a/arch/x86/mm/mmap.c b/arch/x86/mm/mmap.c > index c90c20904a60..f3f52c5e2fd6 100644 > --- a/arch/x86/mm/mmap.c > +++ b/arch/x86/mm/mmap.c > @@ -165,6 +165,8 @@ unsigned long get_mmap_base(int is_legacy) > > const char *arch_vma_name(struct vm_area_struct *vma) > { > + if (vma->vm_flags & VM_SHADOW_STACK) > + return "[shadow stack]"; > return NULL; > } > But why here? CONFIG_ARCH_HAS_SHADOW_STACK implies that there will be more than one arch that supports shadow stack. The name has to come from generic code too, no? -- Kiryl Shutsemau / Kirill A. Shutemov