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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 1E113C43381 for ; Mon, 1 Apr 2019 17:56:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CEBDE2084B for ; Mon, 1 Apr 2019 17:56:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554141403; bh=U6VH4tJMwBji+xr3jucaKUTaZ+jXNLtFA0JAelIZNQI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=YCdF0eyW1ugTNdbEyuoQ1uhdddxH8djx46R+bSV00cKzUrQEU6uRHyuarzqO+PIKP GSryh7XIdAV818KeQv7aKErD3aBGoN42NA/5GM6avznGYQ5/mh90SEc3WwCyAp920l 1tuDbAVL9cl/ODdO+9/LFxeS01LlJBdBzACQYJNM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731600AbfDARVR (ORCPT ); Mon, 1 Apr 2019 13:21:17 -0400 Received: from mail.kernel.org ([198.145.29.99]:49840 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731546AbfDARVR (ORCPT ); Mon, 1 Apr 2019 13:21:17 -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 C3BA4206DD; Mon, 1 Apr 2019 17:21:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1554139276; bh=U6VH4tJMwBji+xr3jucaKUTaZ+jXNLtFA0JAelIZNQI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Za5Ha7hA5d4VIg+rvTXMzgIGhhdYDmGxHAJHmbFHTY30XnUb3PAMvHcUUwdeMUTdp LzrHzlalbB6sTJabFn+WoLQ9iIh9vARzkiIMzdB5KwEhUCZcVQFwM7hq9WkP3nLdPS pZZteEdhEVWbh7gJeYqmEcphlJjOYUrq1pu6Q4DA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Michal Suchanek , Michael Ellerman Subject: [PATCH 4.14 028/107] powerpc/64: Use barrier_nospec in syscall entry Date: Mon, 1 Apr 2019 19:01:43 +0200 Message-Id: <20190401170048.326257686@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190401170045.246405031@linuxfoundation.org> References: <20190401170045.246405031@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Michael Ellerman commit 51973a815c6b46d7b23b68d6af371ad1c9d503ca upstream. Our syscall entry is done in assembly so patch in an explicit barrier_nospec. Based on a patch by Michal Suchanek. Signed-off-by: Michal Suchanek Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/kernel/entry_64.S | 10 ++++++++++ 1 file changed, 10 insertions(+) --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -36,6 +36,7 @@ #include #include #include +#include #include #ifdef CONFIG_PPC_BOOK3S #include @@ -179,6 +180,15 @@ system_call: /* label this so stack tr clrldi r8,r8,32 15: slwi r0,r0,4 + + barrier_nospec_asm + /* + * Prevent the load of the handler below (based on the user-passed + * system call number) being speculatively executed until the test + * against NR_syscalls and branch to .Lsyscall_enosys above has + * committed. + */ + ldx r12,r11,r0 /* Fetch system call handler [ptr] */ mtctr r12 bctrl /* Call handler */