From patchwork Thu Apr 1 16:57:44 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Abeni X-Patchwork-Id: 414868 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=-15.8 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 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 D4FFDC43460 for ; Thu, 1 Apr 2021 18:03:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 97C80611BD for ; Thu, 1 Apr 2021 18:03:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236978AbhDASDQ (ORCPT ); Thu, 1 Apr 2021 14:03:16 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:40483 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236446AbhDAR6h (ORCPT ); Thu, 1 Apr 2021 13:58:37 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1617299917; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=gOPtje+FyDAgtorSzzokEKCOA5PME5R2rkhYp/Wn4fU=; b=PeNg3F4gBr983T7qUmh7RE61XPSvQAphX+YaAOFXzco2jT4q0IIDNyb0cv/JLNHaGu26HJ MaSm/2ca1NidTSG/VNFBgaHK4GE2zTPa6uHcg8TvLqt+S4WXKWHioghwZVpnwLA3XsdEI7 EAHuRRZ5PciyDH75+C65j1L6w2S/pTE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-331-HbE_SiGZPQ-ANp_LaR5DsA-1; Thu, 01 Apr 2021 12:58:10 -0400 X-MC-Unique: HbE_SiGZPQ-ANp_LaR5DsA-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id AB49C6D242; Thu, 1 Apr 2021 16:58:09 +0000 (UTC) Received: from gerbillo.redhat.com (ovpn-114-240.ams2.redhat.com [10.36.114.240]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7316919C46; Thu, 1 Apr 2021 16:58:08 +0000 (UTC) From: Paolo Abeni To: netdev@vger.kernel.org Cc: mptcp@lists.linux.dev, "David S. Miller" , Jakub Kicinski Subject: [PATCH net 1/2] mptcp: forbit mcast-related sockopt on MPTCP sockets Date: Thu, 1 Apr 2021 18:57:44 +0200 Message-Id: In-Reply-To: References: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org 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 --- net/mptcp/protocol.c | 45 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 1590b9d4cde2..e06cea0a3c54 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -2878,6 +2878,48 @@ 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) { @@ -2886,6 +2928,9 @@ 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);