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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 A9C55C433EF for ; Mon, 18 Jun 2018 09:56:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 64263208A6 for ; Mon, 18 Jun 2018 09:56:53 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 64263208A6 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965614AbeFRJ4v (ORCPT ); Mon, 18 Jun 2018 05:56:51 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:54956 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935593AbeFRITw (ORCPT ); Mon, 18 Jun 2018 04:19:52 -0400 Received: from localhost (LFbn-1-12247-202.w90-92.abo.wanadoo.fr [90.92.61.202]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id 3D5ABBAD; Mon, 18 Jun 2018 08:19:51 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mark Rutland , Catalin Marinas , Will Deacon , Sasha Levin Subject: [PATCH 4.16 106/279] arm64: fix possible spectre-v1 in ptrace_hbp_get_event() Date: Mon, 18 Jun 2018 10:11:31 +0200 Message-Id: <20180618080613.211434591@linuxfoundation.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20180618080608.851973560@linuxfoundation.org> References: <20180618080608.851973560@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Mark Rutland [ Upstream commit 19791a7ca674fb3009bb068260e852a2f05b605c ] It's possible for userspace to control idx. Sanitize idx when using it as an array index. Found by smatch. Signed-off-by: Mark Rutland Cc: Catalin Marinas Cc: Will Deacon Signed-off-by: Will Deacon Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- arch/arm64/kernel/ptrace.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -25,6 +25,7 @@ #include #include #include +#include #include #include #include @@ -249,15 +250,20 @@ static struct perf_event *ptrace_hbp_get switch (note_type) { case NT_ARM_HW_BREAK: - if (idx < ARM_MAX_BRP) - bp = tsk->thread.debug.hbp_break[idx]; + if (idx >= ARM_MAX_BRP) + goto out; + idx = array_index_nospec(idx, ARM_MAX_BRP); + bp = tsk->thread.debug.hbp_break[idx]; break; case NT_ARM_HW_WATCH: - if (idx < ARM_MAX_WRP) - bp = tsk->thread.debug.hbp_watch[idx]; + if (idx >= ARM_MAX_WRP) + goto out; + idx = array_index_nospec(idx, ARM_MAX_WRP); + bp = tsk->thread.debug.hbp_watch[idx]; break; } +out: return bp; }