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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 B19F1C433DF for ; Tue, 26 May 2020 19:04:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8D292208A7 for ; Tue, 26 May 2020 19:04:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590519880; bh=C5RUA5PleN6pmherb3qSxADrS/EbTQI2T3y1YchV8eg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=AFmvy0B2iqa5kfRpG03UOcy7MX26czybPwmHSOPdJy5ovg6iFsvrLiomvoiT+tzCX VIuC4CRXpY7Tn4przoj5oJMQZ/5zGJDxdAovDWUqFqOfdQ5B51nvOTcSjezNGmn7xq VIw/bqUU19qrCWUhHoIzsViBt5joJ5US/Q7lmzzw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391390AbgEZTEj (ORCPT ); Tue, 26 May 2020 15:04:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:60328 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390485AbgEZTEi (ORCPT ); Tue, 26 May 2020 15:04:38 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 05A3A2086A; Tue, 26 May 2020 19:04:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590519877; bh=C5RUA5PleN6pmherb3qSxADrS/EbTQI2T3y1YchV8eg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MZDzXkUY2ezRE/NARSdu56QRM9TbcF2jF8kDmNBgrtaqSvccYIQuMiNhgdvqSm9+5 9nuuuDh2oyZ47bcZbFq0PUuP0dZYYfyDtNcFnxK/JUI9DrUX56K5mn/lBvkhXoEzYO 1otTLrucc0Wtf+7EuseA9ix5aj92uXyT+cv3bm0k= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Michael Ellerman , Sasha Levin Subject: [PATCH 4.19 50/81] powerpc/64s: Disable STRICT_KERNEL_RWX Date: Tue, 26 May 2020 20:53:25 +0200 Message-Id: <20200526183932.737734715@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200526183923.108515292@linuxfoundation.org> References: <20200526183923.108515292@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Michael Ellerman [ Upstream commit 8659a0e0efdd975c73355dbc033f79ba3b31e82c ] Several strange crashes have been eventually traced back to STRICT_KERNEL_RWX and its interaction with code patching. Various paths in our ftrace, kprobes and other patching code need to be hardened against patching failures, otherwise we can end up running with partially/incorrectly patched ftrace paths, kprobes or jump labels, which can then cause strange crashes. Although fixes for those are in development, they're not -rc material. There also seem to be problems with the underlying strict RWX logic, which needs further debugging. So for now disable STRICT_KERNEL_RWX on 64-bit to prevent people from enabling the option and tripping over the bugs. Fixes: 1e0fc9d1eb2b ("powerpc/Kconfig: Enable STRICT_KERNEL_RWX for some configs") Cc: stable@vger.kernel.org # v4.13+ Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200520133605.972649-1-mpe@ellerman.id.au Signed-off-by: Sasha Levin --- arch/powerpc/Kconfig | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index da48a2ca272e..f38d153d2586 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -139,7 +139,7 @@ config PPC select ARCH_HAS_MEMBARRIER_CALLBACKS select ARCH_HAS_SCALED_CPUTIME if VIRT_CPU_ACCOUNTING_NATIVE select ARCH_HAS_SG_CHAIN - select ARCH_HAS_STRICT_KERNEL_RWX if ((PPC_BOOK3S_64 || PPC32) && !HIBERNATION) + select ARCH_HAS_STRICT_KERNEL_RWX if (PPC32 && !HIBERNATION) select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST select ARCH_HAS_UACCESS_FLUSHCACHE if PPC64 select ARCH_HAS_UBSAN_SANITIZE_ALL -- 2.25.1