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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 608E9C19F2D for ; Tue, 9 Aug 2022 18:12:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345392AbiHISMn (ORCPT ); Tue, 9 Aug 2022 14:12:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57668 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345987AbiHISMH (ORCPT ); Tue, 9 Aug 2022 14:12:07 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AA51A32C; Tue, 9 Aug 2022 11:05:12 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 0B87461139; Tue, 9 Aug 2022 18:05:09 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 74DCBC433B5; Tue, 9 Aug 2022 18:05:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1660068308; bh=Du+LfgidnyUZQYmLnNKvCIdplUELRrxtwIDyhwydf1w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mKqV7p74prUtXw2hybko4cx71BtsKc84SGD+8/EGR7ko4zmivNIt4lw6g0Tvi4ao3 WVUpJhjtAA+PhVHHvCq0O2R8pzeT5kZPSnzMvPBocIm+Wnf6G5MjohD7fqy5gmdM1Q inptmYEcEmAPvEL+E+uHX/ycDoueEs9mbw5bmIJI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Peter Collingbourne , Will Deacon , Ard Biesheuvel , Catalin Marinas Subject: [PATCH 5.15 16/30] arm64: set UXN on swapper page tables Date: Tue, 9 Aug 2022 20:00:41 +0200 Message-Id: <20220809175514.891266119@linuxfoundation.org> X-Mailer: git-send-email 2.37.1 In-Reply-To: <20220809175514.276643253@linuxfoundation.org> References: <20220809175514.276643253@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Peter Collingbourne [ This issue was fixed upstream by accident in c3cee924bd85 ("arm64: head: cover entire kernel image in initial ID map") as part of a large refactoring of the arm64 boot flow. This simple fix is therefore preferred for -stable backporting ] On a system that implements FEAT_EPAN, read/write access to the idmap is denied because UXN is not set on the swapper PTEs. As a result, idmap_kpti_install_ng_mappings panics the kernel when accessing __idmap_kpti_flag. Fix it by setting UXN on these PTEs. Fixes: 18107f8a2df6 ("arm64: Support execute-only permissions with Enhanced PAN") Cc: # 5.15 Link: https://linux-review.googlesource.com/id/Ic452fa4b4f74753e54f71e61027e7222a0fae1b1 Signed-off-by: Peter Collingbourne Acked-by: Will Deacon Cc: Ard Biesheuvel Cc: Catalin Marinas Link: https://lore.kernel.org/r/20220719234909.1398992-1-pcc@google.com Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman --- arch/arm64/include/asm/kernel-pgtable.h | 4 ++-- arch/arm64/kernel/head.S | 2 +- 2 files changed, 3 insertions(+), 3 deletions(-) --- a/arch/arm64/include/asm/kernel-pgtable.h +++ b/arch/arm64/include/asm/kernel-pgtable.h @@ -103,8 +103,8 @@ /* * Initial memory map attributes. */ -#define SWAPPER_PTE_FLAGS (PTE_TYPE_PAGE | PTE_AF | PTE_SHARED) -#define SWAPPER_PMD_FLAGS (PMD_TYPE_SECT | PMD_SECT_AF | PMD_SECT_S) +#define SWAPPER_PTE_FLAGS (PTE_TYPE_PAGE | PTE_AF | PTE_SHARED | PTE_UXN) +#define SWAPPER_PMD_FLAGS (PMD_TYPE_SECT | PMD_SECT_AF | PMD_SECT_S | PMD_SECT_UXN) #if ARM64_KERNEL_USES_PMD_MAPS #define SWAPPER_MM_MMUFLAGS (PMD_ATTRINDX(MT_NORMAL) | SWAPPER_PMD_FLAGS) --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -285,7 +285,7 @@ SYM_FUNC_START_LOCAL(__create_page_table subs x1, x1, #64 b.ne 1b - mov x7, SWAPPER_MM_MMUFLAGS + mov_q x7, SWAPPER_MM_MMUFLAGS /* * Create the identity mapping.