From patchwork Wed Mar 3 18:43:38 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Abeni X-Patchwork-Id: 1446805 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lists.01.org (client-ip=2001:19d0:306:5::1; helo=ml01.01.org; envelope-from=mptcp-bounces@lists.01.org; receiver=) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=RQVx9zby; dkim-atps=neutral Received: from ml01.01.org (ml01.01.org [IPv6:2001:19d0:306:5::1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4DrNFL4b5yz9sCD for ; Thu, 4 Mar 2021 05:44:06 +1100 (AEDT) Received: from ml01.vlan13.01.org (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id B785E100EB35B; Wed, 3 Mar 2021 10:44:01 -0800 (PST) Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=63.128.21.124; helo=us-smtp-delivery-124.mimecast.com; envelope-from=pabeni@redhat.com; receiver= Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [63.128.21.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 4BC64100EB350 for ; Wed, 3 Mar 2021 10:44:00 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1614797039; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=n1m7M3G+mA2ltakkBZHhyfCISIxhYHvehGSywpVmV1c=; b=RQVx9zbyfCMWHpiJrfRxGkQ9KEAmsK/WORpLJp/y95Do2NWAHC4X0MGi6XGqTtxM5p0s+K 9CR++2Z8IEOLMjXHaKkZbQZSYOHt9SGqCAHuOnBHbnZMJUfqmJoflsbvc94hTtWRQwWLnZ fTkvSzKd486UsT8/UrOWo+6ZSreuVCc= 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-172-LViiufXINd2z4eMoJKqy2g-1; Wed, 03 Mar 2021 13:43:57 -0500 X-MC-Unique: LViiufXINd2z4eMoJKqy2g-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id BD8B7193578B for ; Wed, 3 Mar 2021 18:43:56 +0000 (UTC) Received: from gerbillo.redhat.com (ovpn-112-100.ams2.redhat.com [10.36.112.100]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0388510016DB; Wed, 3 Mar 2021 18:43:55 +0000 (UTC) From: Paolo Abeni To: mptcp@lists.01.org Date: Wed, 3 Mar 2021 19:43:38 +0100 Message-Id: <65ee09253b5e42cb100f914f059bdb0bb61dc0c9.1614796802.git.pabeni@redhat.com> In-Reply-To: References: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=pabeni@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Message-ID-Hash: RMWCRANNUPAQBE5NW7DT5M3DJ6EX6A6E X-Message-ID-Hash: RMWCRANNUPAQBE5NW7DT5M3DJ6EX6A6E X-MailFrom: pabeni@redhat.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; suspicious-header CC: fwestpha@redhat.com X-Mailman-Version: 3.1.1 Precedence: list Subject: [MPTCP] [RFC v2 PATCH 1/2] mptcp: only admit explicitly supported sockopt List-Id: Discussions regarding MPTCP upstreaming Archived-At: List-Archive: List-Help: List-Post: List-Subscribe: List-Unsubscribe: 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 --- v1 -> v2: - switch from blacklist to whitelist A note on optname order. For each sol level, I tried to follow the order used by the corresponding relevant setsockopt(), with the following additional contraint: [1] opt which should currently work correctly with no changes come first [2] than opt that need some impl effort, but should not cause bugs/splat ATM [3] then opt that are really a no-op - and currently work as intended [4] (commented out) unsupported opt come last, with related reasoning. Note that [2] is likely too wide. This is intended as to start discussion. Looks like fixing issue/170 will require a bit of time :( --- net/mptcp/protocol.c | 215 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 215 insertions(+) diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index d6b3112fac299..6a8c3f46f30a4 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -2877,6 +2877,218 @@ static int mptcp_setsockopt_v6(struct mptcp_sock *msk, int optname, return ret; } +static bool mptcp_supported_sockopt(int level, int optname) +{ + if (level == SOL_SOCKET) { + switch (optname) { + case SO_DEBUG: + case SO_REUSEPORT: + case SO_REUSEADDR: + + /* the following 23 need a better implementation, + * but are quite common we want to preserve them + */ + case SO_BINDTODEVICE: + case SO_SNDBUF: + case SO_SNDBUFFORCE: + case SO_RCVBUF: + case SO_RCVBUFFORCE: + case SO_KEEPALIVE: + case SO_PRIORITY: + case SO_LINGER: + case SO_TIMESTAMP_OLD: + case SO_TIMESTAMP_NEW: + case SO_TIMESTAMPNS_OLD: + case SO_TIMESTAMPNS_NEW: + case SO_TIMESTAMPING_OLD: + case SO_TIMESTAMPING_NEW: + case SO_RCVLOWAT: + case SO_RCVTIMEO_OLD: + case SO_RCVTIMEO_NEW: + case SO_MARK: + case SO_INCOMING_CPU: + case SO_BINDTOIFINDEX: +#ifdef CONFIG_NET_RX_BUSY_POLL + case SO_BUSY_POLL: + case SO_PREFER_BUSY_POLL: + case SO_BUSY_POLL_BUDGET: +#endif + + /* next ten are no-op for plain TCP */ + case SO_NO_CHECK: + case SO_DONTROUTE: + case SO_BROADCAST: + case SO_BSDCOMPAT: + case SO_PASSCRED: + case SO_PASSSEC: + case SO_RXQ_OVFL: + case SO_WIFI_STATUS: + case SO_NOFCS: + case SO_SELECT_ERR_QUEUE: + + /* SO_OOBINLINE is not supported, let's avoid the related mess */ + /* SO_ATTACH_FILTER, SO_ATTACH_BPF, SO_ATTACH_REUSEPORT_CBPF, + * SO_DETACH_REUSEPORT_BPF, SO_DETACH_FILTER, SO_LOCK_FILTER, + * we must be careful with subflows + */ + /* SO_ATTACH_REUSEPORT_EBPF is not supported, at it checks + * explicitly the sk_protocol field + */ + /* SO_PEEK_OFF is unsupported, as it is for plain TCP */ + /* SO_MAX_PACING_RATE is unsupported, we must be careful with subflows */ + /* SO_CNX_ADVICE is currently unsupported, could possibly be relevant, + * but likely needs careful design + */ + /* SO_ZEROCOPY is currently unsupported, TODO in sndmsg */ + /* SO_TXTIME is currently unsupported */ + return true; + } + return false; + } + if (level == SOL_IP) { + switch (optname) { + /* should work fine */ + case IP_FREEBIND: + case IP_TRANSPARENT: + + /* the following nine control cmsg */ + case IP_PKTINFO: + case IP_RECVTTL: + case IP_RECVTOS: + case IP_RECVOPTS: + case IP_RETOPTS: + case IP_PASSSEC: + case IP_RECVORIGDSTADDR: + case IP_CHECKSUM: + case IP_RECVFRAGSIZE: + + /* common stuff that need some love */ + case IP_TOS: + case IP_TTL: + case IP_BIND_ADDRESS_NO_PORT: + case IP_MTU_DISCOVER: + case IP_RECVERR: + + /* possibly less common may deserve some love */ + case IP_MINTTL: + + /* the following is apparently a no-op for plain TCP */ + case IP_RECVERR_RFC4884: + + /* IP_OPTIONS is not supported, needs subflow care */ + /* IP_HDRINCL, IP_NODEFRAG are not supported, RAW specific */ + /* IP_MULTICAST_TTL, IP_MULTICAST_LOOP, IP_UNICAST_IF, + * IP_ADD_MEMBERSHIP, IP_ADD_SOURCE_MEMBERSHIP, IP_DROP_MEMBERSHIP, + * IP_DROP_SOURCE_MEMBERSHIP, IP_BLOCK_SOURCE, IP_UNBLOCK_SOURCE, + * MCAST_JOIN_GROUP, MCAST_LEAVE_GROUP MCAST_JOIN_SOURCE_GROUP, + * MCAST_LEAVE_SOURCE_GROUP, MCAST_BLOCK_SOURCE, MCAST_UNBLOCK_SOURCE, + * MCAST_MSFILTER, IP_MULTICAST_ALL are not supported, better not deal with mcast stuff + */ + /* IP_IPSEC_POLICY, IP_XFRM_POLICY are nut supported, unrelated here */ + return true; + } + return false; + } + if (level == SOL_IPV6) { + switch (optname) { + case IPV6_V6ONLY: + + /* the following 14 control cmsg */ + case IPV6_RECVPKTINFO: + case IPV6_2292PKTINFO: + case IPV6_RECVHOPLIMIT: + case IPV6_2292HOPLIMIT: + case IPV6_RECVRTHDR: + case IPV6_2292RTHDR: + case IPV6_RECVHOPOPTS: + case IPV6_2292HOPOPTS: + case IPV6_RECVDSTOPTS: + case IPV6_2292DSTOPTS: + case IPV6_RECVTCLASS: + case IPV6_FLOWINFO: + case IPV6_RECVPATHMTU: + case IPV6_RECVORIGDSTADDR: + case IPV6_RECVFRAGSIZE: + + /* the following 14 need some love but are quite common */ + case IPV6_TCLASS: + case IPV6_TRANSPARENT: + case IPV6_FREEBIND: + case IPV6_PKTINFO: + case IPV6_2292PKTOPTIONS: + case IPV6_UNICAST_HOPS: + case IPV6_MTU_DISCOVER: + case IPV6_MTU: + case IPV6_RECVERR: + case IPV6_FLOWINFO_SEND: + case IPV6_FLOWLABEL_MGR: + case IPV6_MINHOPCOUNT: + case IPV6_DONTFRAG: + case IPV6_AUTOFLOWLABEL: + + /* the following one is a no-op for plain TCP */ + case IPV6_RECVERR_RFC4884: + + /* IPV6_HOPOPTS, IPV6_RTHDRDSTOPTS, IPV6_RTHDR, IPV6_DSTOPTS are + * not supported + */ + /* IPV6_MULTICAST_HOPS, IPV6_MULTICAST_LOOP, IPV6_UNICAST_IF, + * * IPV6_MULTICAST_IF, IPV6_ADDRFORM, + * IPV6_ADD_MEMBERSHIP, IPV6_DROP_MEMBERSHIP, IPV6_JOIN_ANYCAST, + * IPV6_LEAVE_ANYCAST, IPV6_MULTICAST_ALL, MCAST_JOIN_GROUP, MCAST_LEAVE_GROUP, + * MCAST_JOIN_SOURCE_GROUP, MCAST_LEAVE_SOURCE_GROUP, + * MCAST_BLOCK_SOURCE, MCAST_UNBLOCK_SOURCE, MCAST_MSFILTER + * are not supported better not deal with mcast + */ + /* IPV6_ROUTER_ALERT, IPV6_ROUTER_ALERT_ISOLATE are not supported, since are evil */ + + /* IPV6_IPSEC_POLICY, IPV6_XFRM_POLICY are nut supported */ + /* IPV6_ADDR_PREFERENCES is not supported, we must be careful with subflows */ + return true; + } + return false; + } + if (level == SOL_TCP) { + switch (optname) { + /* the following 2 are no-op or should work just fine */ + case TCP_THIN_DUPACK: + case TCP_DEFER_ACCEPT: + + /* the following 18 need some love */ + case TCP_MAXSEG: + case TCP_NODELAY: + case TCP_THIN_LINEAR_TIMEOUTS: + case TCP_CONGESTION: + case TCP_ULP: + case TCP_CORK: + case TCP_KEEPIDLE: + case TCP_KEEPINTVL: + case TCP_KEEPCNT: + case TCP_SYNCNT: + case TCP_SAVE_SYN: + case TCP_LINGER2: + case TCP_WINDOW_CLAMP: + case TCP_QUICKACK: + case TCP_USER_TIMEOUT: + case TCP_TIMESTAMP: + case TCP_NOTSENT_LOWAT: + case TCP_TX_DELAY: + + /* TCP_MD5SIG, TCP_MD5SIG_EXT are not supported, MD5 is not compatible with MPTCP */ + + /* TCP_REPAIR, TCP_REPAIR_QUEUE, TCP_QUEUE_SEQ, TCP_REPAIR_OPTIONS, + * TCP_REPAIR_WINDOW are not supported, better avoid this mess + */ + /* TCP_FASTOPEN_KEY, TCP_FASTOPEN TCP_FASTOPEN_CONNECT, TCP_FASTOPEN_NO_COOKIE, + * are not supported fastopen is currently unsupported + */ + /* TCP_INQ is currently unsupported, needs some recvmsg work */ + return true; + } + } + return false; +} + static int mptcp_setsockopt(struct sock *sk, int level, int optname, sockptr_t optval, unsigned int optlen) { @@ -2885,6 +3097,9 @@ static int mptcp_setsockopt(struct sock *sk, int level, int optname, pr_debug("msk=%p", msk); + if (!mptcp_supported_sockopt(level, optname)) + return -ENOPROTOOPT; + if (level == SOL_SOCKET) return mptcp_setsockopt_sol_socket(msk, optname, optval, optlen); From patchwork Wed Mar 3 18:43:39 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paolo Abeni X-Patchwork-Id: 1446803 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lists.01.org (client-ip=198.145.21.10; helo=ml01.01.org; envelope-from=mptcp-bounces@lists.01.org; receiver=) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; 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Wed, 3 Mar 2021 18:43:57 +0000 (UTC) Received: from gerbillo.redhat.com (ovpn-112-100.ams2.redhat.com [10.36.112.100]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1EFE610016DB; Wed, 3 Mar 2021 18:43:56 +0000 (UTC) From: Paolo Abeni To: mptcp@lists.01.org Date: Wed, 3 Mar 2021 19:43:39 +0100 Message-Id: <30e5b4c37fb98deb22b63f1eb6423de321f46222.1614796802.git.pabeni@redhat.com> In-Reply-To: References: MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=pabeni@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Message-ID-Hash: 75GRXUE37O3YK7AHMNBK4SLUIGRUH63D X-Message-ID-Hash: 75GRXUE37O3YK7AHMNBK4SLUIGRUH63D X-MailFrom: pabeni@redhat.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; suspicious-header CC: fwestpha@redhat.com X-Mailman-Version: 3.1.1 Precedence: list Subject: [MPTCP] [RFC v2 PATCH 2/2] mptcp: revert "mptcp: provide subflow aware release function"$ ....$ List-Id: Discussions regarding MPTCP upstreaming Archived-At: List-Archive: List-Help: List-Post: List-Subscribe: List-Unsubscribe: This commit reverts ad98dd37051e ("mptcp: provide subflow aware release function"). The latter introduced a deadlock spotted by syzkaller and is not needed anymore after the previous commit. Fixes: ad98dd37051e ("mptcp: provide subflow aware release function") Signed-off-by: Paolo Abeni $ --- net/mptcp/protocol.c | 55 ++------------------------------------------ 1 file changed, 2 insertions(+), 53 deletions(-) diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 6a8c3f46f30a4..911050373ff62 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -11,7 +11,6 @@ #include #include #include -#include #include #include #include @@ -20,7 +19,6 @@ #include #if IS_ENABLED(CONFIG_MPTCP_IPV6) #include -#include #endif #include #include @@ -3630,34 +3628,10 @@ static __poll_t mptcp_poll(struct file *file, struct socket *sock, return mask; } -static int mptcp_release(struct socket *sock) -{ - struct mptcp_subflow_context *subflow; - struct sock *sk = sock->sk; - struct mptcp_sock *msk; - - if (!sk) - return 0; - - lock_sock(sk); - - msk = mptcp_sk(sk); - - mptcp_for_each_subflow(msk, subflow) { - struct sock *ssk = mptcp_subflow_tcp_sock(subflow); - - ip_mc_drop_socket(ssk); - } - - release_sock(sk); - - return inet_release(sock); -} - static const struct proto_ops mptcp_stream_ops = { .family = PF_INET, .owner = THIS_MODULE, - .release = mptcp_release, + .release = inet_release, .bind = mptcp_bind, .connect = mptcp_stream_connect, .socketpair = sock_no_socketpair, @@ -3755,35 +3729,10 @@ void __init mptcp_proto_init(void) } #if IS_ENABLED(CONFIG_MPTCP_IPV6) -static int mptcp6_release(struct socket *sock) -{ - struct mptcp_subflow_context *subflow; - struct mptcp_sock *msk; - struct sock *sk = sock->sk; - - if (!sk) - return 0; - - lock_sock(sk); - - msk = mptcp_sk(sk); - - mptcp_for_each_subflow(msk, subflow) { - struct sock *ssk = mptcp_subflow_tcp_sock(subflow); - - ip_mc_drop_socket(ssk); - ipv6_sock_mc_close(ssk); - ipv6_sock_ac_close(ssk); - } - - release_sock(sk); - return inet6_release(sock); -} - static const struct proto_ops mptcp_v6_stream_ops = { .family = PF_INET6, .owner = THIS_MODULE, - .release = mptcp6_release, + .release = inet6_release, .bind = mptcp_bind, .connect = mptcp_stream_connect, .socketpair = sock_no_socketpair,