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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 686E0C433EF for ; Tue, 16 Nov 2021 01:08:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4FB5560EB9 for ; Tue, 16 Nov 2021 01:08:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1377168AbhKPBLq (ORCPT ); Mon, 15 Nov 2021 20:11:46 -0500 Received: from mail.kernel.org ([198.145.29.99]:44610 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S245409AbhKOTUa (ORCPT ); Mon, 15 Nov 2021 14:20:30 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 1DAC961104; Mon, 15 Nov 2021 18:34:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1637001244; bh=MJEqHK6HqMPcivDSNlbWsDQZ2QEeUHS3TSn0z9Dy7Co=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=D06A9MEhw/L2DdyVNmN2TgP7mIX3TxOa/NSgT2PtNPObFEvqEYes7jsX4m5ksxd4M CoszkSVIJlsVF2avSqhMQ4AhyfbWOAa744ZeRgxA6ew4c1gd9sKBxqA+iHfyv9z55k 0gVZpwWicTzTQg4kz7QOV1Ef+U7Eskqcn9/O+Kyo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eugene Syromiatnikov , Jeremy Kerr , Jakub Kicinski Subject: [PATCH 5.15 116/917] mctp: handle the struct sockaddr_mctp padding fields Date: Mon, 15 Nov 2021 17:53:31 +0100 Message-Id: <20211115165432.683691015@linuxfoundation.org> X-Mailer: git-send-email 2.33.1 In-Reply-To: <20211115165428.722074685@linuxfoundation.org> References: <20211115165428.722074685@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Eugene Syromiatnikov commit 1e4b50f06d970d8da3474d2a0354450416710bda upstream. In order to have the padding fields actually usable in the future, there have to be checks that user space doesn't supply non-zero garbage there. It is also worth setting these padding fields to zero, unless it is known that they have been already zeroed. Cc: stable@vger.kernel.org # v5.15 Fixes: 5a20dd46b8b84593 ("mctp: Be explicit about struct sockaddr_mctp padding") Signed-off-by: Eugene Syromiatnikov Acked-by: Jeremy Kerr Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- net/mctp/af_mctp.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) --- a/net/mctp/af_mctp.c +++ b/net/mctp/af_mctp.c @@ -30,6 +30,12 @@ static int mctp_release(struct socket *s return 0; } +/* Generic sockaddr checks, padding checks only so far */ +static bool mctp_sockaddr_is_ok(const struct sockaddr_mctp *addr) +{ + return !addr->__smctp_pad0 && !addr->__smctp_pad1; +} + static int mctp_bind(struct socket *sock, struct sockaddr *addr, int addrlen) { struct sock *sk = sock->sk; @@ -49,6 +55,9 @@ static int mctp_bind(struct socket *sock /* it's a valid sockaddr for MCTP, cast and do protocol checks */ smctp = (struct sockaddr_mctp *)addr; + if (!mctp_sockaddr_is_ok(smctp)) + return -EINVAL; + lock_sock(sk); /* TODO: allow rebind */ @@ -83,6 +92,8 @@ static int mctp_sendmsg(struct socket *s return -EINVAL; if (addr->smctp_family != AF_MCTP) return -EINVAL; + if (!mctp_sockaddr_is_ok(addr)) + return -EINVAL; if (addr->smctp_tag & ~(MCTP_TAG_MASK | MCTP_TAG_OWNER)) return -EINVAL; @@ -172,11 +183,13 @@ static int mctp_recvmsg(struct socket *s addr = msg->msg_name; addr->smctp_family = AF_MCTP; + addr->__smctp_pad0 = 0; addr->smctp_network = cb->net; addr->smctp_addr.s_addr = hdr->src; addr->smctp_type = type; addr->smctp_tag = hdr->flags_seq_tag & (MCTP_HDR_TAG_MASK | MCTP_HDR_FLAG_TO); + addr->__smctp_pad1 = 0; msg->msg_namelen = sizeof(*addr); }