From patchwork Tue Apr 5 07:26:51 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 556984 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 57ED4C433F5 for ; Tue, 5 Apr 2022 11:24:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1359825AbiDELU5 (ORCPT ); Tue, 5 Apr 2022 07:20:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44178 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1349260AbiDEJtb (ORCPT ); Tue, 5 Apr 2022 05:49:31 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 86A63AB; Tue, 5 Apr 2022 02:43:27 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 2657F6164D; Tue, 5 Apr 2022 09:43:27 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 32838C385A1; Tue, 5 Apr 2022 09:43:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1649151806; bh=SFZhGojlTJsFtEcOoR6TsDZqCuHRKYKgaXsoBWxvPMc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=wsAaXplorpXAHaQGyH1G7Y0yl10x3YT6jInzObjwGDzf5w1hHxsrlGI6hC6UnzTFH imryDRU1uXYiAiIeB9+GNNfJ+myvZwqxv4DxMnwdbRkxJuAzUjmZuxXnJHu3MpqzMS aFdSz6jnsSDjhcZhGDtq5vf6LsYu4sQVGuCKMolA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+2339c27f5c66c652843e@syzkaller.appspotmail.com, Oliver Hartkopp , Marc Kleine-Budde Subject: [PATCH 5.15 549/913] can: isotp: sanitize CAN ID checks in isotp_bind() Date: Tue, 5 Apr 2022 09:26:51 +0200 Message-Id: <20220405070356.303888570@linuxfoundation.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220405070339.801210740@linuxfoundation.org> References: <20220405070339.801210740@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Oliver Hartkopp commit 3ea566422cbde9610c2734980d1286ab681bb40e upstream. Syzbot created an environment that lead to a state machine status that can not be reached with a compliant CAN ID address configuration. The provided address information consisted of CAN ID 0x6000001 and 0xC28001 which both boil down to 11 bit CAN IDs 0x001 in sending and receiving. Sanitize the SFF/EFF CAN ID values before performing the address checks. Fixes: e057dd3fc20f ("can: add ISO 15765-2:2016 transport protocol") Link: https://lore.kernel.org/all/20220316164258.54155-1-socketcan@hartkopp.net Reported-by: syzbot+2339c27f5c66c652843e@syzkaller.appspotmail.com Signed-off-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde Signed-off-by: Greg Kroah-Hartman --- net/can/isotp.c | 38 ++++++++++++++++++++------------------ 1 file changed, 20 insertions(+), 18 deletions(-) --- a/net/can/isotp.c +++ b/net/can/isotp.c @@ -1104,6 +1104,7 @@ static int isotp_bind(struct socket *soc struct net *net = sock_net(sk); int ifindex; struct net_device *dev; + canid_t tx_id, rx_id; int err = 0; int notify_enetdown = 0; int do_rx_reg = 1; @@ -1111,8 +1112,18 @@ static int isotp_bind(struct socket *soc if (len < ISOTP_MIN_NAMELEN) return -EINVAL; - if (addr->can_addr.tp.tx_id & (CAN_ERR_FLAG | CAN_RTR_FLAG)) - return -EADDRNOTAVAIL; + /* sanitize tx/rx CAN identifiers */ + tx_id = addr->can_addr.tp.tx_id; + if (tx_id & CAN_EFF_FLAG) + tx_id &= (CAN_EFF_FLAG | CAN_EFF_MASK); + else + tx_id &= CAN_SFF_MASK; + + rx_id = addr->can_addr.tp.rx_id; + if (rx_id & CAN_EFF_FLAG) + rx_id &= (CAN_EFF_FLAG | CAN_EFF_MASK); + else + rx_id &= CAN_SFF_MASK; if (!addr->can_ifindex) return -ENODEV; @@ -1124,21 +1135,13 @@ static int isotp_bind(struct socket *soc do_rx_reg = 0; /* do not validate rx address for functional addressing */ - if (do_rx_reg) { - if (addr->can_addr.tp.rx_id == addr->can_addr.tp.tx_id) { - err = -EADDRNOTAVAIL; - goto out; - } - - if (addr->can_addr.tp.rx_id & (CAN_ERR_FLAG | CAN_RTR_FLAG)) { - err = -EADDRNOTAVAIL; - goto out; - } + if (do_rx_reg && rx_id == tx_id) { + err = -EADDRNOTAVAIL; + goto out; } if (so->bound && addr->can_ifindex == so->ifindex && - addr->can_addr.tp.rx_id == so->rxid && - addr->can_addr.tp.tx_id == so->txid) + rx_id == so->rxid && tx_id == so->txid) goto out; dev = dev_get_by_index(net, addr->can_ifindex); @@ -1162,8 +1165,7 @@ static int isotp_bind(struct socket *soc ifindex = dev->ifindex; if (do_rx_reg) - can_rx_register(net, dev, addr->can_addr.tp.rx_id, - SINGLE_MASK(addr->can_addr.tp.rx_id), + can_rx_register(net, dev, rx_id, SINGLE_MASK(rx_id), isotp_rcv, sk, "isotp", sk); dev_put(dev); @@ -1183,8 +1185,8 @@ static int isotp_bind(struct socket *soc /* switch to new settings */ so->ifindex = ifindex; - so->rxid = addr->can_addr.tp.rx_id; - so->txid = addr->can_addr.tp.tx_id; + so->rxid = rx_id; + so->txid = tx_id; so->bound = 1; out: