From patchwork Fri Jun 25 08:25:55 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jianguo Wu X-Patchwork-Id: 12344051 Received: from m12-18.163.com (m12-18.163.com [220.181.12.18]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 70AE26D10 for ; Fri, 25 Jun 2021 08:26:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id; bh=Yunsv5jSqQKGvIorS3 oP+Peqd+jW65jIyS11f7q8X40=; b=B339o4nGQl9NnmaUJ23dBfQN60o2MxWJGn ab1uF314RwDehpcJvahFN0kko1ae2IRR79Gz2w9s3m3bmXA16UyrfwBAQ/Yiyp6G x9bveBLaZSbvEZKZF4uLE+QJrs7I3D2rID1RIdIA2g+Yi3ni/59JCri8g39i3jYZ KOL0qsgmE= Received: from localhost.localdomain (unknown [36.111.140.26]) by smtp14 (Coremail) with SMTP id EsCowAAnK+MXk9VgPJySrQ--.35196S3; Fri, 25 Jun 2021 16:26:02 +0800 (CST) From: wujianguo106@163.com To: mptcp@lists.linux.dev Cc: pabeni@redhat.com, mathew.j.martineau@linux.intel.com Subject: [PATCH mptcp-net v7 1/5] mptcp: fix warning in __skb_flow_dissect() when do syn cookie for subflow join Date: Fri, 25 Jun 2021 16:25:55 +0800 Message-Id: <1624609559-6786-2-git-send-email-wujianguo106@163.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1624609559-6786-1-git-send-email-wujianguo106@163.com> References: <1624609559-6786-1-git-send-email-wujianguo106@163.com> X-CM-TRANSID: EsCowAAnK+MXk9VgPJySrQ--.35196S3 X-Coremail-Antispam: 1Uf129KBjvJXoWxGFy7Kw4fKw15AFW5WFWruFg_yoWrZF43pr 43GrWDGrW8Jwn8Jr4YyFW7Xrn0gr4vvFWkG3Wayrn7JFn8Gwn2qFy8Jr409Fy7GrWqg347 Kr1DX3WkKFn7ZaUanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x07jxZ2-UUUUU= X-Originating-IP: [36.111.140.26] X-CM-SenderInfo: 5zxmxt5qjx0iiqw6il2tof0z/xtbB9wO8kF2MZYH9pQAAs1 Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: From: Jianguo Wu I did stress test with wrk(https://github.com/wg/wrk) and webfsd(https://github.com/ourway/webfsd) with the assistance of mptcp-tools(https://github.com/pabeni/mptcp-tools): Server side: ./use_mptcp.sh webfsd -4 -R /tmp/ -p 8099 Client side: ./use_mptcp.sh wrk -c 200 -d 30 -t 4 http://192.168.174.129:8099/ and got the following warning message: [ 55.552626] TCP: request_sock_subflow: Possible SYN flooding on port 8099. Sending cookies. Check SNMP counters. [ 55.553024] ------------[ cut here ]------------ [ 55.553027] WARNING: CPU: 0 PID: 10 at net/core/flow_dissector.c:984 __skb_flow_dissect+0x280/0x1650 ... [ 55.553117] CPU: 0 PID: 10 Comm: ksoftirqd/0 Not tainted 5.12.0+ #18 [ 55.553121] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 02/27/2020 [ 55.553124] RIP: 0010:__skb_flow_dissect+0x280/0x1650 ... [ 55.553133] RSP: 0018:ffffb79580087770 EFLAGS: 00010246 [ 55.553137] RAX: 0000000000000000 RBX: ffffffff8ddb58e0 RCX: ffffb79580087888 [ 55.553139] RDX: ffffffff8ddb58e0 RSI: ffff8f7e4652b600 RDI: 0000000000000000 [ 55.553141] RBP: ffffb79580087858 R08: 0000000000000000 R09: 0000000000000008 [ 55.553143] R10: 000000008c622965 R11: 00000000d3313a5b R12: ffff8f7e4652b600 [ 55.553146] R13: ffff8f7e465c9062 R14: 0000000000000000 R15: ffffb79580087888 [ 55.553149] FS: 0000000000000000(0000) GS:ffff8f7f75e00000(0000) knlGS:0000000000000000 [ 55.553152] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 55.553154] CR2: 00007f73d1d19000 CR3: 0000000135e10004 CR4: 00000000003706f0 [ 55.553160] Call Trace: [ 55.553166] ? __sha256_final+0x67/0xd0 [ 55.553173] ? sha256+0x7e/0xa0 [ 55.553177] __skb_get_hash+0x57/0x210 [ 55.553182] subflow_init_req_cookie_join_save+0xac/0xc0 [ 55.553189] subflow_check_req+0x474/0x550 [ 55.553195] ? ip_route_output_key_hash+0x67/0x90 [ 55.553200] ? xfrm_lookup_route+0x1d/0xa0 [ 55.553207] subflow_v4_route_req+0x8e/0xd0 [ 55.553212] tcp_conn_request+0x31e/0xab0 [ 55.553218] ? selinux_socket_sock_rcv_skb+0x116/0x210 [ 55.553224] ? tcp_rcv_state_process+0x179/0x6d0 [ 55.553229] tcp_rcv_state_process+0x179/0x6d0 [ 55.553235] tcp_v4_do_rcv+0xaf/0x220 [ 55.553239] tcp_v4_rcv+0xce4/0xd80 [ 55.553243] ? ip_route_input_rcu+0x246/0x260 [ 55.553248] ip_protocol_deliver_rcu+0x35/0x1b0 [ 55.553253] ip_local_deliver_finish+0x44/0x50 [ 55.553258] ip_local_deliver+0x6c/0x110 [ 55.553262] ? ip_rcv_finish_core.isra.19+0x5a/0x400 [ 55.553267] ip_rcv+0xd1/0xe0 ... After debugging, I found in __skb_flow_dissect(), skb->dev and skb->sk are both NULL, then net is NULL, and trigger WARN_ON_ONCE(!net), actually net is always NULL in this code path, as skb->dev is set to NULL in tcp_v4_rcv(), and skb->sk is never set. Code snippet in __skb_flow_dissect() that trigger warning: 975 if (skb) { 976 if (!net) { 977 if (skb->dev) 978 net = dev_net(skb->dev); 979 else if (skb->sk) 980 net = sock_net(skb->sk); 981 } 982 } 983 984 WARN_ON_ONCE(!net); So, using seq and transport header derived hash. Fixes: 9466a1ccebbe("mptcp: enable JOIN requests even if cookies are in use"). Suggested-by: Paolo Abeni Suggested-by: Florian Westphal Signed-off-by: Jianguo Wu --- net/mptcp/syncookies.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/net/mptcp/syncookies.c b/net/mptcp/syncookies.c index abe0fd0..3712778 100644 --- a/net/mptcp/syncookies.c +++ b/net/mptcp/syncookies.c @@ -37,7 +37,21 @@ struct join_entry { static u32 mptcp_join_entry_hash(struct sk_buff *skb, struct net *net) { - u32 i = skb_get_hash(skb) ^ net_hash_mix(net); + static u32 mptcp_join_hash_secret __read_mostly; + struct tcphdr *th = tcp_hdr(skb); + u32 seq, i; + + net_get_random_once(&mptcp_join_hash_secret, + sizeof(mptcp_join_hash_secret)); + + if (th->syn) + seq = TCP_SKB_CB(skb)->seq; + else + seq = TCP_SKB_CB(skb)->seq - 1; + + i = jhash_3words(seq, net_hash_mix(net), + (__force __u32)th->source << 16 | (__force __u32)th->dest, + mptcp_join_hash_secret); return i % ARRAY_SIZE(join_entries); } From patchwork Fri Jun 25 08:25:56 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jianguo Wu X-Patchwork-Id: 12344049 Received: from m12-18.163.com (m12-18.163.com [220.181.12.18]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 2B23A2FB2 for ; Fri, 25 Jun 2021 08:26:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id; bh=oVwxxQqg9LgPACKg5H RT/dVdDa8LWQi6BWHlU87hNPY=; b=iKWNZQUWok8WwiRZGr1aWdZWznwSIb1EDk ln+UaeQnqP00Ee2W37XI9W2sXAXJQR8a3x0mq+3er97am4EbCiOalXA5Jumh7B/m Ms4CpiaSIX0pcWOrc8brIq/Q7kkxI0t23/bVWM8f1Ptz44XumYSH+/01YipEv3aV +8BYOaQ70= Received: from localhost.localdomain (unknown [36.111.140.26]) by smtp14 (Coremail) with SMTP id EsCowAAnK+MXk9VgPJySrQ--.35196S4; Fri, 25 Jun 2021 16:26:04 +0800 (CST) From: wujianguo106@163.com To: mptcp@lists.linux.dev Cc: pabeni@redhat.com, mathew.j.martineau@linux.intel.com Subject: [PATCH mptcp-net v7 2/5] mptcp: remove redundant req destruct in subflow_check_req() Date: Fri, 25 Jun 2021 16:25:56 +0800 Message-Id: <1624609559-6786-3-git-send-email-wujianguo106@163.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1624609559-6786-1-git-send-email-wujianguo106@163.com> References: <1624609559-6786-1-git-send-email-wujianguo106@163.com> X-CM-TRANSID: EsCowAAnK+MXk9VgPJySrQ--.35196S4 X-Coremail-Antispam: 1Uf129KBjvJXoW7Cr4Dtw47WFWrtryktF4ktFb_yoW8Gryfpr sxXw1FyrZxZFyakF4rJr4DZrn0gayFvFn5GFyY9asxJr4qqws3KF1UWr4UuFy3Aa1kKay7 GF43tFnxX3Wq9aUanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x07jSsjbUUUUU= X-Originating-IP: [36.111.140.26] X-CM-SenderInfo: 5zxmxt5qjx0iiqw6il2tof0z/xtbB+AS8kF2MZYKzTgAAsb Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: From: Jianguo Wu In subflow_check_req(), if subflow sport is mismatch, will put msk, destroy token, and destruct req, then return -EPERM, which can be done by subflow_req_destructor() via: tcp_conn_request() |--__reqsk_free() |--subflow_req_destructor() So we should remove these redundant code, otherwise will call tcp_v4_reqsk_destructor() twice, and may double free inet_rsk(req)->ireq_opt. Fixes: 5bc56388c74f ("mptcp: add port number check for MP_JOIN") Signed-off-by: Jianguo Wu --- net/mptcp/subflow.c | 5 ----- 1 file changed, 5 deletions(-) diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index 0b5d4a3..3a849fb 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -214,11 +214,6 @@ static int subflow_check_req(struct request_sock *req, ntohs(inet_sk(sk_listener)->inet_sport), ntohs(inet_sk((struct sock *)subflow_req->msk)->inet_sport)); if (!mptcp_pm_sport_in_anno_list(subflow_req->msk, sk_listener)) { - sock_put((struct sock *)subflow_req->msk); - mptcp_token_destroy_request(req); - tcp_request_sock_ops.destructor(req); - subflow_req->msk = NULL; - subflow_req->mp_join = 0; SUBFLOW_REQ_INC_STATS(req, MPTCP_MIB_MISMATCHPORTSYNRX); return -EPERM; } From patchwork Fri Jun 25 08:25:57 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jianguo Wu X-Patchwork-Id: 12344059 Received: from m12-18.163.com (m12-18.163.com [220.181.12.18]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 222E16D0E for ; Fri, 25 Jun 2021 08:26:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id; bh=mD97yaMOvV9ufafCWS zfkocaaSedpCOJd7JS5AND7A0=; b=F/2171bcdi2JLcA4abVt3benV5F9av58ji T6/y35/FsCKV8wFU/+5FHjI+A+5/tqF+pa3d0Ax3R2g5jqNEYACIrJw8sFBn44SW kGnUbHfAvqR+hQlyquy6+L4jxLUSDBx4JIx3sco+OPKXk56HnO6+7lnTGFbJwLkW MlJV8n6fk= Received: from localhost.localdomain (unknown [36.111.140.26]) by smtp14 (Coremail) with SMTP id EsCowAAnK+MXk9VgPJySrQ--.35196S5; Fri, 25 Jun 2021 16:26:04 +0800 (CST) From: wujianguo106@163.com To: mptcp@lists.linux.dev Cc: pabeni@redhat.com, mathew.j.martineau@linux.intel.com Subject: [PATCH mptcp-net v7 3/5] mptcp: fix syncookie process if mptcp can not_accept new subflow Date: Fri, 25 Jun 2021 16:25:57 +0800 Message-Id: <1624609559-6786-4-git-send-email-wujianguo106@163.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1624609559-6786-1-git-send-email-wujianguo106@163.com> References: <1624609559-6786-1-git-send-email-wujianguo106@163.com> X-CM-TRANSID: EsCowAAnK+MXk9VgPJySrQ--.35196S5 X-Coremail-Antispam: 1Uf129KBjvJXoWxZF43ur18GrW7XF18Kw43trb_yoW5Ar1rpr 4UXrW7tr1fJFy3GFWftw4DZw1j9FZYyrZxJa15K347Awn8Zws3Kry8KFyI9ryxCFs7GFyY qrs2q3WqvFnrCaDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x07jNHUgUUUUU= X-Originating-IP: [36.111.140.26] X-CM-SenderInfo: 5zxmxt5qjx0iiqw6il2tof0z/xtbBiB28kFaD-a-uYQAAsx Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: From: Jianguo Wu Lots of "TCP: tcp_fin: Impossible, sk->sk_state=7" in client side when doing stress testing using wrk and webfsd. There are at least two cases may trigger this warning: 1.mptcp is in syncookie, and server recv MP_JOIN SYN request, in subflow_check_req(), the mptcp_can_accept_new_subflow() return false, so subflow_init_req_cookie_join_save() isn't called, i.e. not store the data present in the MP_JOIN syn request and the random nonce in hash table - join_entries[], but still send synack. When recv 3rd-ack, mptcp_token_join_cookie_init_state() will return false, and 3rd-ack is dropped, then if mptcp conn is closed by client, client will send a DATA_FIN and a MPTCP FIN, the DATA_FIN doesn't have MP_CAPABLE or MP_JOIN, so mptcp_subflow_init_cookie_req() will return 0, and pass the cookie check, MP_JOIN request is fallback to normal TCP. Server will send a TCP FIN if closed, in client side, when process TCP FIN, it will do reset, the code path is: tcp_data_queue()->mptcp_incoming_options() ->check_fully_established()->mptcp_subflow_reset(). mptcp_subflow_reset() will set sock state to TCP_CLOSE, so tcp_fin will hit TCP_CLOSE, and print the warning. 2.mptcp is in syncookie, and server recv 3rd-ack, in mptcp_subflow_init_cookie_req(), mptcp_can_accept_new_subflow() return false, and subflow_req->mp_join is not set to 1, so in subflow_syn_recv_sock() will not reset the MP_JOIN subflow, but fallback to normal TCP, and then the same thing happens when server will send a TCP FIN if closed. For case1, subflow_check_req() return -EPERM, then tcp_conn_request() will drop MP_JOIN SYN. For case2, let subflow_syn_recv_sock() call mptcp_can_accept_new_subflow(), and do fatal fallback, send reset. Fixes: 9466a1ccebbe("mptcp: enable JOIN requests even if cookies are in use") Signed-off-by: Jianguo Wu --- net/mptcp/subflow.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index 3a849fb..f3f1358 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -225,6 +225,8 @@ static int subflow_check_req(struct request_sock *req, if (unlikely(req->syncookie)) { if (mptcp_can_accept_new_subflow(subflow_req->msk)) subflow_init_req_cookie_join_save(subflow_req, skb); + else + return -EPERM; } pr_debug("token=%u, remote_nonce=%u msk=%p", subflow_req->token, @@ -264,9 +266,7 @@ int mptcp_subflow_init_cookie_req(struct request_sock *req, if (!mptcp_token_join_cookie_init_state(subflow_req, skb)) return -EINVAL; - if (mptcp_can_accept_new_subflow(subflow_req->msk)) - subflow_req->mp_join = 1; - + subflow_req->mp_join = 1; subflow_req->ssn_offset = TCP_SKB_CB(skb)->seq - 1; } From patchwork Fri Jun 25 08:25:58 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jianguo Wu X-Patchwork-Id: 12344055 Received: from m12-18.163.com (m12-18.163.com [220.181.12.18]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 4A5A76D0E for ; Fri, 25 Jun 2021 08:26:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id; bh=Y31JeG225RRU3Aij+u BaoAsYPyKDDpV1cBtspR68BwE=; b=bw1lWZs3kIbFCvZw0UgfQ/XQCnpm8Pw1Ta wt6mGj9bkSeQbDuMO7pDXBB1BF/UztInIImWX46JWxoFeNd8DKI9LYMcZfF7FpHw qtTxuPEodme36QtEonaz9Qm4Ez2gQ8S5vHPVXIoe9ClPfxQK4F5WugONL3QCAW06 Vxb84wBQc= Received: from localhost.localdomain (unknown [36.111.140.26]) by smtp14 (Coremail) with SMTP id EsCowAAnK+MXk9VgPJySrQ--.35196S6; Fri, 25 Jun 2021 16:26:05 +0800 (CST) From: wujianguo106@163.com To: mptcp@lists.linux.dev Cc: pabeni@redhat.com, mathew.j.martineau@linux.intel.com Subject: [PATCH mptcp-net v7 4/5] mptcp: avoid processing packet if a subflow reset Date: Fri, 25 Jun 2021 16:25:58 +0800 Message-Id: <1624609559-6786-5-git-send-email-wujianguo106@163.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1624609559-6786-1-git-send-email-wujianguo106@163.com> References: <1624609559-6786-1-git-send-email-wujianguo106@163.com> X-CM-TRANSID: EsCowAAnK+MXk9VgPJySrQ--.35196S6 X-Coremail-Antispam: 1Uf129KBjvJXoW3Ar45CFyrXFW8Ar4UtF48tFb_yoW7tF45pF 1DGw13Jr4kXFWfWr4xAFWkZr1S9w4FkFZ8G3yUKw45Arn8Gw4IkFy5t3Wakr43GFWj9asx JrZ2qFy5uF17AFJanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x07jh5rxUUUUU= X-Originating-IP: [36.111.140.26] X-CM-SenderInfo: 5zxmxt5qjx0iiqw6il2tof0z/1tbiNx28kFWBk7oOkwAAsm Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: From: Jianguo Wu If check_fully_established() causes a subflow reset, it should not continue to process the packet in tcp_data_queue(). Add a return value to mptcp_incoming_options(), and return 0 if a subflow has been reset, else return 1. Then drop the packet in tcp_data_queue()/tcp_rcv_state_process() if mptcp_incoming_options() return 0. Fixes: d582484726c4 ("mptcp: fix fallback for MP_JOIN subflows") Signed-off-by: Jianguo Wu --- include/net/mptcp.h | 5 +++-- net/ipv4/tcp_input.c | 19 +++++++++++++++---- net/mptcp/options.c | 22 ++++++++++++++-------- 3 files changed, 32 insertions(+), 14 deletions(-) diff --git a/include/net/mptcp.h b/include/net/mptcp.h index cb580b0..cbd511c 100644 --- a/include/net/mptcp.h +++ b/include/net/mptcp.h @@ -105,7 +105,7 @@ bool mptcp_synack_options(const struct request_sock *req, unsigned int *size, bool mptcp_established_options(struct sock *sk, struct sk_buff *skb, unsigned int *size, unsigned int remaining, struct mptcp_out_options *opts); -void mptcp_incoming_options(struct sock *sk, struct sk_buff *skb); +int mptcp_incoming_options(struct sock *sk, struct sk_buff *skb); void mptcp_write_options(__be32 *ptr, const struct tcp_sock *tp, struct mptcp_out_options *opts); @@ -227,9 +227,10 @@ static inline bool mptcp_established_options(struct sock *sk, return false; } -static inline void mptcp_incoming_options(struct sock *sk, +static inline int mptcp_incoming_options(struct sock *sk, struct sk_buff *skb) { + return 1; } static inline void mptcp_skb_ext_move(struct sk_buff *to, diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 7d5e59f..4bacd7d 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -4247,6 +4247,9 @@ void tcp_reset(struct sock *sk, struct sk_buff *skb) { trace_tcp_receive_reset(sk); + /* mptcp can't tell us to ignore reset pkts, + * so just ignore the return value of mptcp_incoming_options(). + */ if (sk_is_mptcp(sk)) mptcp_incoming_options(sk, skb); @@ -4941,8 +4944,13 @@ static void tcp_data_queue(struct sock *sk, struct sk_buff *skb) bool fragstolen; int eaten; - if (sk_is_mptcp(sk)) - mptcp_incoming_options(sk, skb); + /* If a subflow has been reset, the packet should not continue + * to be processed, drop the packet. + */ + if (sk_is_mptcp(sk) && !mptcp_incoming_options(sk, skb)) { + __kfree_skb(skb); + return; + } if (TCP_SKB_CB(skb)->seq == TCP_SKB_CB(skb)->end_seq) { __kfree_skb(skb); @@ -6523,8 +6531,11 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb) case TCP_CLOSING: case TCP_LAST_ACK: if (!before(TCP_SKB_CB(skb)->seq, tp->rcv_nxt)) { - if (sk_is_mptcp(sk)) - mptcp_incoming_options(sk, skb); + /* If a subflow has been reset, the packet should not + * continue to be processed, drop the packet. + */ + if (sk_is_mptcp(sk) && !mptcp_incoming_options(sk, skb)) + goto discard; break; } fallthrough; diff --git a/net/mptcp/options.c b/net/mptcp/options.c index b5850af..f4842b5 100644 --- a/net/mptcp/options.c +++ b/net/mptcp/options.c @@ -856,7 +856,8 @@ bool mptcp_synack_options(const struct request_sock *req, unsigned int *size, static bool check_fully_established(struct mptcp_sock *msk, struct sock *ssk, struct mptcp_subflow_context *subflow, struct sk_buff *skb, - struct mptcp_options_received *mp_opt) + struct mptcp_options_received *mp_opt, + bool *subflow_is_rst) { /* here we can process OoO, in-window pkts, only in-sequence 4th ack * will make the subflow fully established @@ -938,6 +939,7 @@ static bool check_fully_established(struct mptcp_sock *msk, struct sock *ssk, return true; reset: + *subflow_is_rst = true; mptcp_subflow_reset(ssk); return false; } @@ -1035,12 +1037,14 @@ static bool add_addr_hmac_valid(struct mptcp_sock *msk, return hmac == mp_opt->ahmac; } -void mptcp_incoming_options(struct sock *sk, struct sk_buff *skb) +/* Return 0 if a subflow has been reset, else return 1 */ +int mptcp_incoming_options(struct sock *sk, struct sk_buff *skb) { struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk); struct mptcp_sock *msk = mptcp_sk(subflow->conn); struct mptcp_options_received mp_opt; struct mptcp_ext *mpext; + bool subflow_is_rst = false; if (__mptcp_check_fallback(msk)) { /* Keep it simple and unconditionally trigger send data cleanup and @@ -1053,12 +1057,12 @@ void mptcp_incoming_options(struct sock *sk, struct sk_buff *skb) __mptcp_check_push(subflow->conn, sk); __mptcp_data_acked(subflow->conn); mptcp_data_unlock(subflow->conn); - return; + return 1; } mptcp_get_options(sk, skb, &mp_opt); - if (!check_fully_established(msk, sk, subflow, skb, &mp_opt)) - return; + if (!check_fully_established(msk, sk, subflow, skb, &mp_opt, &subflow_is_rst)) + return subflow_is_rst ? 0 : 1; if (mp_opt.fastclose && msk->local_key == mp_opt.rcvr_key) { @@ -1100,7 +1104,7 @@ void mptcp_incoming_options(struct sock *sk, struct sk_buff *skb) } if (!mp_opt.dss) - return; + return 1; /* we can't wait for recvmsg() to update the ack_seq, otherwise * monodirectional flows will stuck @@ -1119,12 +1123,12 @@ void mptcp_incoming_options(struct sock *sk, struct sk_buff *skb) schedule_work(&msk->work)) sock_hold(subflow->conn); - return; + return 1; } mpext = skb_ext_add(skb, SKB_EXT_MPTCP); if (!mpext) - return; + return 1; memset(mpext, 0, sizeof(*mpext)); @@ -1153,6 +1157,8 @@ void mptcp_incoming_options(struct sock *sk, struct sk_buff *skb) if (mpext->csum_reqd) mpext->csum = mp_opt.csum; } + + return 1; } static void mptcp_set_rwin(const struct tcp_sock *tp) From patchwork Fri Jun 25 08:25:59 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jianguo Wu X-Patchwork-Id: 12344053 Received: from m12-18.163.com (m12-18.163.com [220.181.12.18]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 2B2612FB3 for ; Fri, 25 Jun 2021 08:26:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id; bh=5deExUksRhz+ynlf38 oqAkXMoTdflt/vR9pMZk6sVRU=; b=GxPd7PIoG+bFmqaUIJiAgXrhH8YTr7r/Gu 494+CW/1tYwlhTIMM6kgrW/HT+5IbiTSI5NdYIH3zAr8NqtsUsceJiBtvEiRp8SI Ef7l5v1swsT0HkgceQlTmQ6c1d7K/ldoSx8IBFV8300CgbVBdMNZK+EPhDaZup2R RoTkDCH+Q= Received: from localhost.localdomain (unknown [36.111.140.26]) by smtp14 (Coremail) with SMTP id EsCowAAnK+MXk9VgPJySrQ--.35196S7; Fri, 25 Jun 2021 16:26:06 +0800 (CST) From: wujianguo106@163.com To: mptcp@lists.linux.dev Cc: pabeni@redhat.com, mathew.j.martineau@linux.intel.com Subject: [PATCH mptcp-net v7 5/5] selftests: mptcp: fix case multiple subflows limited by server Date: Fri, 25 Jun 2021 16:25:59 +0800 Message-Id: <1624609559-6786-6-git-send-email-wujianguo106@163.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1624609559-6786-1-git-send-email-wujianguo106@163.com> References: <1624609559-6786-1-git-send-email-wujianguo106@163.com> X-CM-TRANSID: EsCowAAnK+MXk9VgPJySrQ--.35196S7 X-Coremail-Antispam: 1Uf129KBjvdXoW7JFWDArW3Aw47Ww15Wr4UArb_yoWkKrgEgF 4xtFyDArs8ZFyUtF18Cr15CrWrK3sxu397Kr10vw13Jw1jy3W5WFWkJF1Du3Z3G390934a gFs2yw1Yyw1jgjkaLaAFLSUrUUUUUb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUvcSsGvfC2KfnxnUUI43ZEXa7IU0qg43UUUUU== X-Originating-IP: [36.111.140.26] X-CM-SenderInfo: 5zxmxt5qjx0iiqw6il2tof0z/xtbBSR68kFaD-BfesgAAsp Precedence: bulk X-Mailing-List: mptcp@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: From: Jianguo Wu After patch "mptcp: fix syncookie process if mptcp can not_accept new subflow", If subflow is limited, MP_JOIN SYN is dropped, and no SYN/ACK will be replied. So in case "multiple subflows limited by server", the expected SYN/ACK number should be 1. Reported-by: kernel test robot Signed-off-by: Jianguo Wu --- tools/testing/selftests/net/mptcp/mptcp_join.sh | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/testing/selftests/net/mptcp/mptcp_join.sh b/tools/testing/selftests/net/mptcp/mptcp_join.sh index 9a191c1..f02f4de 100755 --- a/tools/testing/selftests/net/mptcp/mptcp_join.sh +++ b/tools/testing/selftests/net/mptcp/mptcp_join.sh @@ -1409,7 +1409,7 @@ syncookies_tests() ip netns exec $ns2 ./pm_nl_ctl add 10.0.3.2 flags subflow ip netns exec $ns2 ./pm_nl_ctl add 10.0.2.2 flags subflow run_tests $ns1 $ns2 10.0.1.1 - chk_join_nr "subflows limited by server w cookies" 2 2 1 + chk_join_nr "subflows limited by server w cookies" 2 1 1 # test signal address with cookies reset_with_cookies