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=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 1E7E0C433B4 for ; Mon, 12 Apr 2021 09:36:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E11AD61209 for ; Mon, 12 Apr 2021 09:36:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240942AbhDLJgT (ORCPT ); Mon, 12 Apr 2021 05:36:19 -0400 Received: from mail.kernel.org ([198.145.29.99]:34520 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240453AbhDLJKS (ORCPT ); Mon, 12 Apr 2021 05:10:18 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 905246128B; Mon, 12 Apr 2021 09:05:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1618218331; bh=pwwIQR8D40GkFEQd5LY3Sw6sJgXU5bGx6ZgqABUg0mw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nwfRPscXFMEFpiZ3ewpIBLMbJrp0IQtlIkrztPnRqK9ddw42HbzaY3XiTEx3RnK8P gWNo8iYO+jYRd7oNlQ6M3uMFqMobcjQQarhYbyAJev8KaIepNVkNpW38u/UOMjYXbM 4Ui6bidHhZVpXUKgIyjLeOXfx2IcF6KJttJ5pD64= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Paolo Abeni , Mat Martineau , "David S. Miller" , Sasha Levin Subject: [PATCH 5.11 156/210] mptcp: forbit mcast-related sockopt on MPTCP sockets Date: Mon, 12 Apr 2021 10:41:01 +0200 Message-Id: <20210412084021.192097513@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210412084016.009884719@linuxfoundation.org> References: <20210412084016.009884719@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: Paolo Abeni [ Upstream commit 86581852d7710990d8af9dadfe9a661f0abf2114 ] Unrolling mcast state at msk dismantel time is bug prone, as syzkaller reported: ====================================================== WARNING: possible circular locking dependency detected 5.11.0-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor905/8822 is trying to acquire lock: ffffffff8d678fe8 (rtnl_mutex){+.+.}-{3:3}, at: ipv6_sock_mc_close+0xd7/0x110 net/ipv6/mcast.c:323 but task is already holding lock: ffff888024390120 (sk_lock-AF_INET6){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1600 [inline] ffff888024390120 (sk_lock-AF_INET6){+.+.}-{0:0}, at: mptcp6_release+0x57/0x130 net/mptcp/protocol.c:3507 which lock already depends on the new lock. Instead we can simply forbit any mcast-related setsockopt Fixes: 717e79c867ca5 ("mptcp: Add setsockopt()/getsockopt() socket operations") Signed-off-by: Paolo Abeni Reviewed-by: Mat Martineau Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/mptcp/protocol.c | 45 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 5932b0ebecc3..de9f2509acbe 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -2863,6 +2863,48 @@ static int mptcp_setsockopt_v6(struct mptcp_sock *msk, int optname, return ret; } +static bool mptcp_unsupported(int level, int optname) +{ + if (level == SOL_IP) { + switch (optname) { + case IP_ADD_MEMBERSHIP: + case IP_ADD_SOURCE_MEMBERSHIP: + case IP_DROP_MEMBERSHIP: + case IP_DROP_SOURCE_MEMBERSHIP: + case IP_BLOCK_SOURCE: + case IP_UNBLOCK_SOURCE: + case MCAST_JOIN_GROUP: + case MCAST_LEAVE_GROUP: + case MCAST_JOIN_SOURCE_GROUP: + case MCAST_LEAVE_SOURCE_GROUP: + case MCAST_BLOCK_SOURCE: + case MCAST_UNBLOCK_SOURCE: + case MCAST_MSFILTER: + return true; + } + return false; + } + if (level == SOL_IPV6) { + switch (optname) { + case IPV6_ADDRFORM: + case IPV6_ADD_MEMBERSHIP: + case IPV6_DROP_MEMBERSHIP: + case IPV6_JOIN_ANYCAST: + case IPV6_LEAVE_ANYCAST: + case MCAST_JOIN_GROUP: + case MCAST_LEAVE_GROUP: + case MCAST_JOIN_SOURCE_GROUP: + case MCAST_LEAVE_SOURCE_GROUP: + case MCAST_BLOCK_SOURCE: + case MCAST_UNBLOCK_SOURCE: + case MCAST_MSFILTER: + return true; + } + return false; + } + return false; +} + static int mptcp_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval, unsigned int optlen) { @@ -2871,6 +2913,9 @@ static int mptcp_setsockopt(struct sock *sk, int level, int optname, pr_debug("msk=%p", msk); + if (mptcp_unsupported(level, optname)) + return -ENOPROTOOPT; + if (level == SOL_SOCKET) return mptcp_setsockopt_sol_socket(msk, optname, optval, optlen); -- 2.30.2