From patchwork Fri Feb 18 08:31:28 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Menglong Dong X-Patchwork-Id: 12751070 X-Patchwork-Delegate: kuba@kernel.org 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2096BC433EF for ; Fri, 18 Feb 2022 08:33:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232690AbiBRId1 (ORCPT ); Fri, 18 Feb 2022 03:33:27 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:36770 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232654AbiBRIdG (ORCPT ); Fri, 18 Feb 2022 03:33:06 -0500 Received: from mail-pg1-x544.google.com (mail-pg1-x544.google.com [IPv6:2607:f8b0:4864:20::544]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E5FBA2DD44; Fri, 18 Feb 2022 00:32:48 -0800 (PST) Received: by mail-pg1-x544.google.com with SMTP id s16so7216389pgs.13; Fri, 18 Feb 2022 00:32:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=t1JcfESLshia0hfZycViI4NCFCf3p6OKuHoudYWw9ZA=; b=nW1lmzUWrykSgiE/tTu7hLPrzSoBOmVu8KhT2CwzKOtoEltuMIChHFFssB84S2vJle +i7nMinoTX1xU6o3XQmn9HBfT/HC3R5oYYB/wdWB+fgAL//7DZqE0h2Zw4BSNRbfES3U M+w4/aHF1aO11jpwOMaOW8Xl3hJFr5h0aKZUpHefWt+ZkmkVpBM5IBgEVtoZSKPFClgv LBKX3ZitBWt9+cGHaq+ne6b0C1lWsKhtpVAttUQcHdXb4F1xHIFWzVdSEZwpsvFxIt9W rzMJ5dunERiioXDPTFJ47f/ZxmLoh5VbGw/maw60xDhS5qw/+MAdmnRVTC1RNjGekzwX g41g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=t1JcfESLshia0hfZycViI4NCFCf3p6OKuHoudYWw9ZA=; b=IeVlCLd3mTwl/xQZJggQuJyZI5yHit3cqvZDdPQFpljEsMfjj+LgZuJUzgDWRxRFxN Wq0V5a/65u80qXYDa3kYgD3WGTetoKG535tQiZJDZPmpuYtWalwCeAjdBfF63lzbaZr7 aQo4nIrvU7O3Ha8AtMMy+h7ACEb+yRfyuHJWGMDnTxhk/NgrGV5D9ozwhY99m6nK0CkH sAeoRRo+qy5xxkj7tVCiirM+QpjAMgecp4sL83CmUjaQxBkQAI3tBXSSu6cXBsN/Hz7K a6GdAR8o/U7nxoCut/KXFqKznbqDHEfh9FTMSJrZDiht5TEoaXeSlAJlSDqKuOFGMyEB qUXA== X-Gm-Message-State: AOAM5326Avp2Ixsj99Z+JPaaerTtTsFwBdsTe1H6kH+R0U9Eu76hT7MQ d5+6hyFjoLxx4fzDiKSBWC8= X-Google-Smtp-Source: ABdhPJyYZfppkZR2mWdHy47N4ktkhPj+VteDGTdrW+jkzIQv2uBzjpPCaa3OsFgd0fNHyFwLdijFJg== X-Received: by 2002:a63:3202:0:b0:365:84d4:4705 with SMTP id y2-20020a633202000000b0036584d44705mr5453321pgy.201.1645173168382; Fri, 18 Feb 2022 00:32:48 -0800 (PST) Received: from localhost.localdomain ([203.205.141.113]) by smtp.gmail.com with ESMTPSA id m23sm1963530pff.201.2022.02.18.00.32.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 18 Feb 2022 00:32:47 -0800 (PST) From: menglong8.dong@gmail.com X-Google-Original-From: imagedong@tencent.com To: dsahern@kernel.org, kuba@kernel.org Cc: edumazet@google.com, davem@davemloft.net, rostedt@goodmis.org, mingo@redhat.com, yoshfuji@linux-ipv6.org, ast@kernel.org, daniel@iogearbox.net, hawk@kernel.org, john.fastabend@gmail.com, imagedong@tencent.com, talalahmad@google.com, keescook@chromium.org, ilias.apalodimas@linaro.org, alobakin@pm.me, memxor@gmail.com, atenart@kernel.org, bigeasy@linutronix.de, pabeni@redhat.com, linyunsheng@huawei.com, arnd@arndb.de, yajun.deng@linux.dev, roopa@nvidia.com, willemb@google.com, vvs@virtuozzo.com, cong.wang@bytedance.com, luiz.von.dentz@intel.com, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, flyingpeng@tencent.com Subject: [PATCH net-next v2 4/9] net: tcp: add skb drop reasons to tcp_v{4,6}_inbound_md5_hash() Date: Fri, 18 Feb 2022 16:31:28 +0800 Message-Id: <20220218083133.18031-5-imagedong@tencent.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220218083133.18031-1-imagedong@tencent.com> References: <20220218083133.18031-1-imagedong@tencent.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Menglong Dong Pass the address of drop reason to tcp_v4_inbound_md5_hash() and tcp_v6_inbound_md5_hash() to store the reasons for skb drops when this function fails. Therefore, the drop reason can be passed to kfree_skb_reason() when the skb needs to be freed. Following drop reasons are added: SKB_DROP_REASON_TCP_MD5NOTFOUND SKB_DROP_REASON_TCP_MD5UNEXPECTED SKB_DROP_REASON_TCP_MD5FAILURE SKB_DROP_REASON_TCP_MD5* above correspond to LINUX_MIB_TCPMD5* Signed-off-by: Menglong Dong --- include/linux/skbuff.h | 12 ++++++++++++ include/trace/events/skb.h | 4 ++++ net/ipv4/tcp_ipv4.c | 13 +++++++++---- net/ipv6/tcp_ipv6.c | 11 ++++++++--- 4 files changed, 33 insertions(+), 7 deletions(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index a5adbf6b51e8..46678eb587ff 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -346,6 +346,18 @@ enum skb_drop_reason { * udp packet drop out of * udp_memory_allocated. */ + SKB_DROP_REASON_TCP_MD5NOTFOUND, /* no MD5 hash and one + * expected, corresponding + * to LINUX_MIB_TCPMD5NOTFOUND + */ + SKB_DROP_REASON_TCP_MD5UNEXPECTED, /* MD5 hash and we're not + * expecting one, corresponding + * to LINUX_MIB_TCPMD5UNEXPECTED + */ + SKB_DROP_REASON_TCP_MD5FAILURE, /* MD5 hash and its wrong, + * corresponding to + * LINUX_MIB_TCPMD5FAILURE + */ SKB_DROP_REASON_MAX, }; diff --git a/include/trace/events/skb.h b/include/trace/events/skb.h index cfcfd26399f7..46c06b0be850 100644 --- a/include/trace/events/skb.h +++ b/include/trace/events/skb.h @@ -27,6 +27,10 @@ EM(SKB_DROP_REASON_IP_NOPROTO, IP_NOPROTO) \ EM(SKB_DROP_REASON_SOCKET_RCVBUFF, SOCKET_RCVBUFF) \ EM(SKB_DROP_REASON_PROTO_MEM, PROTO_MEM) \ + EM(SKB_DROP_REASON_TCP_MD5NOTFOUND, TCP_MD5NOTFOUND) \ + EM(SKB_DROP_REASON_TCP_MD5UNEXPECTED, \ + TCP_MD5UNEXPECTED) \ + EM(SKB_DROP_REASON_TCP_MD5FAILURE, TCP_MD5FAILURE) \ EMe(SKB_DROP_REASON_MAX, MAX) #undef EM diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index a3beab01e9a7..d3c417119057 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1412,7 +1412,8 @@ EXPORT_SYMBOL(tcp_v4_md5_hash_skb); /* Called with rcu_read_lock() */ static bool tcp_v4_inbound_md5_hash(const struct sock *sk, const struct sk_buff *skb, - int dif, int sdif) + int dif, int sdif, + enum skb_drop_reason *reason) { #ifdef CONFIG_TCP_MD5SIG /* @@ -1445,11 +1446,13 @@ static bool tcp_v4_inbound_md5_hash(const struct sock *sk, return false; if (hash_expected && !hash_location) { + *reason = SKB_DROP_REASON_TCP_MD5NOTFOUND; NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND); return true; } if (!hash_expected && hash_location) { + *reason = SKB_DROP_REASON_TCP_MD5UNEXPECTED; NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED); return true; } @@ -1462,6 +1465,7 @@ static bool tcp_v4_inbound_md5_hash(const struct sock *sk, NULL, skb); if (genhash || memcmp(hash_location, newhash, 16) != 0) { + *reason = SKB_DROP_REASON_TCP_MD5FAILURE; NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5FAILURE); net_info_ratelimited("MD5 Hash failed for (%pI4, %d)->(%pI4, %d)%s L3 index %d\n", &iph->saddr, ntohs(th->source), @@ -1971,13 +1975,13 @@ static void tcp_v4_fill_cb(struct sk_buff *skb, const struct iphdr *iph, int tcp_v4_rcv(struct sk_buff *skb) { struct net *net = dev_net(skb->dev); + enum skb_drop_reason drop_reason; int sdif = inet_sdif(skb); int dif = inet_iif(skb); const struct iphdr *iph; const struct tcphdr *th; bool refcounted; struct sock *sk; - int drop_reason; int ret; drop_reason = SKB_DROP_REASON_NOT_SPECIFIED; @@ -2025,7 +2029,8 @@ int tcp_v4_rcv(struct sk_buff *skb) struct sock *nsk; sk = req->rsk_listener; - if (unlikely(tcp_v4_inbound_md5_hash(sk, skb, dif, sdif))) { + if (unlikely(tcp_v4_inbound_md5_hash(sk, skb, dif, sdif, + &drop_reason))) { sk_drops_add(sk, skb); reqsk_put(req); goto discard_it; @@ -2099,7 +2104,7 @@ int tcp_v4_rcv(struct sk_buff *skb) goto discard_and_relse; } - if (tcp_v4_inbound_md5_hash(sk, skb, dif, sdif)) + if (tcp_v4_inbound_md5_hash(sk, skb, dif, sdif, &drop_reason)) goto discard_and_relse; nf_reset_ct(skb); diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 0aa17073df1a..1262b790b146 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -775,7 +775,8 @@ static int tcp_v6_md5_hash_skb(char *md5_hash, static bool tcp_v6_inbound_md5_hash(const struct sock *sk, const struct sk_buff *skb, - int dif, int sdif) + int dif, int sdif, + enum skb_drop_reason *reason) { #ifdef CONFIG_TCP_MD5SIG const __u8 *hash_location = NULL; @@ -798,11 +799,13 @@ static bool tcp_v6_inbound_md5_hash(const struct sock *sk, return false; if (hash_expected && !hash_location) { + *reason = SKB_DROP_REASON_TCP_MD5NOTFOUND; NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5NOTFOUND); return true; } if (!hash_expected && hash_location) { + *reason = SKB_DROP_REASON_TCP_MD5UNEXPECTED; NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5UNEXPECTED); return true; } @@ -813,6 +816,7 @@ static bool tcp_v6_inbound_md5_hash(const struct sock *sk, NULL, skb); if (genhash || memcmp(hash_location, newhash, 16) != 0) { + *reason = SKB_DROP_REASON_TCP_MD5FAILURE; NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPMD5FAILURE); net_info_ratelimited("MD5 Hash %s for [%pI6c]:%u->[%pI6c]:%u L3 index %d\n", genhash ? "failed" : "mismatch", @@ -1681,7 +1685,8 @@ INDIRECT_CALLABLE_SCOPE int tcp_v6_rcv(struct sk_buff *skb) struct sock *nsk; sk = req->rsk_listener; - if (tcp_v6_inbound_md5_hash(sk, skb, dif, sdif)) { + if (tcp_v6_inbound_md5_hash(sk, skb, dif, sdif, + &drop_reason)) { sk_drops_add(sk, skb); reqsk_put(req); goto discard_it; @@ -1752,7 +1757,7 @@ INDIRECT_CALLABLE_SCOPE int tcp_v6_rcv(struct sk_buff *skb) goto discard_and_relse; } - if (tcp_v6_inbound_md5_hash(sk, skb, dif, sdif)) + if (tcp_v6_inbound_md5_hash(sk, skb, dif, sdif, &drop_reason)) goto discard_and_relse; if (tcp_filter(sk, skb)) {