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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E5268CA0EE6 for ; Fri, 15 Aug 2025 10:49:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=jH6upNyi8b3O4Ypl4uBmnNawWvdJaZoKkwJtIcfQLw8=; b=sAUlgpFrTPmkolMsQU7/oYNRVb L0X6VolA4l7EOfDmsf+cBDwsM88Q00sgwcV8wMpRqIw36UeH837Ur1OT0dfYwxeXrQG/Cx8YgydhJ Fk4EAHCJvPBOYDp91hw3GR123/JN5QMi2tTBtTFiXd/QTGUjYPePF5GTpmJ9la7FeNShFtyVIPZ8D /SKrF7FJhMbaIDg0JHLff1fSZZsYDlejRugvw/CYXnXkyTyU/tiE2wQ3U5Sl3nGWvkpNoEiIZcmGa +gYBKC+d+nkBSqu4zISrmz7yiMPu4VN9ch+qA17O1w0tpa4eEjJ67XwQadrbx7Zsqrb7C0X5zxFMF +G5VcDGg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1umrzn-00000002FlB-3sJU; Fri, 15 Aug 2025 10:49:15 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1umqEg-00000001w3h-0D6t for linux-arm-kernel@lists.infradead.org; Fri, 15 Aug 2025 08:56:31 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 72FCD1688; Fri, 15 Aug 2025 01:56:21 -0700 (PDT) Received: from e123572-lin.arm.com (e123572-lin.cambridge.arm.com [10.1.194.54]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 053E83F63F; Fri, 15 Aug 2025 01:56:24 -0700 (PDT) From: Kevin Brodsky To: linux-hardening@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Kevin Brodsky , Andrew Morton , Andy Lutomirski , Catalin Marinas , Dave Hansen , David Hildenbrand , Ira Weiny , Jann Horn , Jeff Xu , Joey Gouly , Kees Cook , Linus Walleij , Lorenzo Stoakes , Marc Zyngier , Mark Brown , Matthew Wilcox , Maxwell Bland , "Mike Rapoport (IBM)" , Peter Zijlstra , Pierre Langlois , Quentin Perret , Rick Edgecombe , Ryan Roberts , Thomas Gleixner , Vlastimil Babka , Will Deacon , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, x86@kernel.org Subject: [RFC PATCH v5 13/18] mm: Map page tables with privileged pkey Date: Fri, 15 Aug 2025 09:55:07 +0100 Message-ID: <20250815085512.2182322-14-kevin.brodsky@arm.com> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20250815085512.2182322-1-kevin.brodsky@arm.com> References: <20250815085512.2182322-1-kevin.brodsky@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250815_015630_126086_A767B707 X-CRM114-Status: GOOD ( 11.28 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org If CONFIG_KPKEYS_HARDENED_PGTABLES is enabled, map allocated page table pages using a privileged pkey (KPKEYS_PKEY_PGTABLES), so that page tables can only be written under guard(kpkeys_hardened_pgtables). This patch is a no-op if CONFIG_KPKEYS_HARDENED_PGTABLES is disabled (default). Signed-off-by: Kevin Brodsky --- include/linux/mm.h | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/include/linux/mm.h b/include/linux/mm.h index d9371d992033..4880cb7a4cb9 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -34,6 +34,7 @@ #include #include #include +#include struct mempolicy; struct anon_vma; @@ -2979,6 +2980,8 @@ static inline bool __pagetable_ctor(struct ptdesc *ptdesc) __folio_set_pgtable(folio); lruvec_stat_add_folio(folio, NR_PAGETABLE); + if (kpkeys_protect_pgtable_memory(folio)) + return false; return true; } @@ -2989,6 +2992,7 @@ static inline void pagetable_dtor(struct ptdesc *ptdesc) ptlock_free(ptdesc); __folio_clear_pgtable(folio); lruvec_stat_sub_folio(folio, NR_PAGETABLE); + kpkeys_unprotect_pgtable_memory(folio); } static inline void pagetable_dtor_free(struct ptdesc *ptdesc) -- 2.47.0