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=-7.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,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 7FF6AECDE47 for ; Thu, 8 Nov 2018 22:09:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3870F2147D for ; Thu, 8 Nov 2018 22:09:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="e3+IQYfv" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3870F2147D 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 S1732812AbeKIHq7 (ORCPT ); Fri, 9 Nov 2018 02:46:59 -0500 Received: from mail.kernel.org ([198.145.29.99]:40768 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728473AbeKIHq7 (ORCPT ); Fri, 9 Nov 2018 02:46:59 -0500 Received: from localhost (unknown [208.72.13.198]) (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 52F6D2089F; Thu, 8 Nov 2018 22:09:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1541714967; bh=PKlodnIPaHPk0d6mBDwlfs3skm+Bt7QCFvO8B2Aqvyo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=e3+IQYfv3YJqEtzSilYp5PBvApaCS0NEeoybovoNn9m2fu/Qf5xW8oY1d+ebIVgzi dIFl6GsBJ/Xsy6qf7Nobhz6LaMuSLNfqD8jDNmg0+xirSPVIXOvqrI+KW2iuq9dixp K8a5TlHg4h560V2aVg+q1bpH7ePllTr3ixi1xzXs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Gustavo A. R. Silva" , Doug Ledford Subject: [PATCH 4.18 13/34] RDMA/ucma: Fix Spectre v1 vulnerability Date: Thu, 8 Nov 2018 13:52:42 -0800 Message-Id: <20181108215139.732097529@linuxfoundation.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181108215138.892971755@linuxfoundation.org> References: <20181108215138.892971755@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review 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 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Gustavo A. R. Silva commit a3671a4f973ee9d9621d60166cc3b037c397d604 upstream. hdr.cmd can be indirectly controlled by user-space, hence leading to a potential exploitation of the Spectre variant 1 vulnerability. This issue was detected with the help of Smatch: drivers/infiniband/core/ucma.c:1686 ucma_write() warn: potential spectre issue 'ucma_cmd_table' [r] (local cap) Fix this by sanitizing hdr.cmd before using it to index ucm_cmd_table. Notice that given that speculation windows are large, the policy is to kill the speculation on the first load and not worry if it can be completed with a dependent load/store [1]. [1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2 Cc: stable@vger.kernel.org Signed-off-by: Gustavo A. R. Silva Signed-off-by: Doug Ledford Signed-off-by: Greg Kroah-Hartman --- drivers/infiniband/core/ucma.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/infiniband/core/ucma.c +++ b/drivers/infiniband/core/ucma.c @@ -44,6 +44,8 @@ #include #include +#include + #include #include #include @@ -1676,6 +1678,7 @@ static ssize_t ucma_write(struct file *f if (hdr.cmd >= ARRAY_SIZE(ucma_cmd_table)) return -EINVAL; + hdr.cmd = array_index_nospec(hdr.cmd, ARRAY_SIZE(ucma_cmd_table)); if (hdr.in + sizeof(hdr) > len) return -EINVAL;