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=-7.1 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 DE879C282C6 for ; Thu, 24 Jan 2019 19:44:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id ADDB9218D4 for ; Thu, 24 Jan 2019 19:44:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548359071; bh=wZyRqFt+jIgp4/PVpFC29QAHhFO/G5XE9LZTXsQ4ZNU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=oN/mwrbemrEUWLxHDWJZq+FJc5ebUbAb1bSXvQk+Tk6q/oG0qpMBOxkwxeU7AhK+n 6hUEf5VfR68RUuJOuKb4/Exojdsct/bLMtIM7AWzlxpSN640yXo0brfJSyxqhIQBdI 5BzpQnLqgSfIWl93WSOeV0Jcv1StG79/S9thcYmw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387580AbfAXTob (ORCPT ); Thu, 24 Jan 2019 14:44:31 -0500 Received: from mail.kernel.org ([198.145.29.99]:45292 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388090AbfAXTo3 (ORCPT ); Thu, 24 Jan 2019 14:44:29 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.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 76913218D2; Thu, 24 Jan 2019 19:44:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548359067; bh=wZyRqFt+jIgp4/PVpFC29QAHhFO/G5XE9LZTXsQ4ZNU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vl2EqbrHNBbTzpyyB7Jl6YZcjImRVgnLoFuRSDjF2Q4Omms3u/Prq86O0x0CK7DfI BoPv4ORTTtfMkRnJfjdyo+Hac8eORVfYYkSmadDK41KB2/d96WRvrblDV4BWhOw799 6a57VQ7AzcHLkznna5iq//3Z3GBpkgVqwJp9HJtY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Gustavo A. R. Silva" , Corey Minyard Subject: [PATCH 4.20 125/127] ipmi: msghandler: Fix potential Spectre v1 vulnerabilities Date: Thu, 24 Jan 2019 20:21:11 +0100 Message-Id: <20190124190217.238278077@linuxfoundation.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190124190211.984305387@linuxfoundation.org> References: <20190124190211.984305387@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: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.20-stable review patch. If anyone has any objections, please let me know. ------------------ From: Gustavo A. R. Silva commit a7102c7461794a5bb31af24b08e9e0f50038897a upstream. channel and addr->channel are indirectly controlled by user-space, hence leading to a potential exploitation of the Spectre variant 1 vulnerability. These issues were detected with the help of Smatch: drivers/char/ipmi/ipmi_msghandler.c:1381 ipmi_set_my_address() warn: potential spectre issue 'user->intf->addrinfo' [w] (local cap) drivers/char/ipmi/ipmi_msghandler.c:1401 ipmi_get_my_address() warn: potential spectre issue 'user->intf->addrinfo' [r] (local cap) drivers/char/ipmi/ipmi_msghandler.c:1421 ipmi_set_my_LUN() warn: potential spectre issue 'user->intf->addrinfo' [w] (local cap) drivers/char/ipmi/ipmi_msghandler.c:1441 ipmi_get_my_LUN() warn: potential spectre issue 'user->intf->addrinfo' [r] (local cap) drivers/char/ipmi/ipmi_msghandler.c:2260 check_addr() warn: potential spectre issue 'intf->addrinfo' [r] (local cap) Fix this by sanitizing channel and addr->channel before using them to index user->intf->addrinfo and intf->addrinfo, correspondingly. 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://lore.kernel.org/lkml/20180423164740.GY17484@dhcp22.suse.cz/ Cc: stable@vger.kernel.org Signed-off-by: Gustavo A. R. Silva Signed-off-by: Corey Minyard Signed-off-by: Greg Kroah-Hartman --- drivers/char/ipmi/ipmi_msghandler.c | 26 ++++++++++++++++++-------- 1 file changed, 18 insertions(+), 8 deletions(-) --- a/drivers/char/ipmi/ipmi_msghandler.c +++ b/drivers/char/ipmi/ipmi_msghandler.c @@ -32,6 +32,7 @@ #include #include #include +#include #define IPMI_DRIVER_VERSION "39.2" @@ -1298,10 +1299,12 @@ int ipmi_set_my_address(struct ipmi_user if (!user) return -ENODEV; - if (channel >= IPMI_MAX_CHANNELS) + if (channel >= IPMI_MAX_CHANNELS) { rv = -EINVAL; - else + } else { + channel = array_index_nospec(channel, IPMI_MAX_CHANNELS); user->intf->addrinfo[channel].address = address; + } release_ipmi_user(user, index); return rv; @@ -1318,10 +1321,12 @@ int ipmi_get_my_address(struct ipmi_user if (!user) return -ENODEV; - if (channel >= IPMI_MAX_CHANNELS) + if (channel >= IPMI_MAX_CHANNELS) { rv = -EINVAL; - else + } else { + channel = array_index_nospec(channel, IPMI_MAX_CHANNELS); *address = user->intf->addrinfo[channel].address; + } release_ipmi_user(user, index); return rv; @@ -1338,10 +1343,12 @@ int ipmi_set_my_LUN(struct ipmi_user *us if (!user) return -ENODEV; - if (channel >= IPMI_MAX_CHANNELS) + if (channel >= IPMI_MAX_CHANNELS) { rv = -EINVAL; - else + } else { + channel = array_index_nospec(channel, IPMI_MAX_CHANNELS); user->intf->addrinfo[channel].lun = LUN & 0x3; + } release_ipmi_user(user, index); return rv; @@ -1358,10 +1365,12 @@ int ipmi_get_my_LUN(struct ipmi_user *us if (!user) return -ENODEV; - if (channel >= IPMI_MAX_CHANNELS) + if (channel >= IPMI_MAX_CHANNELS) { rv = -EINVAL; - else + } else { + channel = array_index_nospec(channel, IPMI_MAX_CHANNELS); *address = user->intf->addrinfo[channel].lun; + } release_ipmi_user(user, index); return rv; @@ -2184,6 +2193,7 @@ static int check_addr(struct ipmi_smi * { if (addr->channel >= IPMI_MAX_CHANNELS) return -EINVAL; + addr->channel = array_index_nospec(addr->channel, IPMI_MAX_CHANNELS); *lun = intf->addrinfo[addr->channel].lun; *saddr = intf->addrinfo[addr->channel].address; return 0;