From patchwork Thu Apr 11 10:01:54 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: xu.xin16@zte.com.cn X-Patchwork-Id: 13625674 Received: from mxct.zte.com.cn (mxct.zte.com.cn [58.251.27.85]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0C5A8145B26; Thu, 11 Apr 2024 10:10:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=58.251.27.85 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712830243; cv=none; b=CwuwJT5mM+RI0UfZ0lplnBwHb7vUvJnRJSKHFhAb36H0igR75x4HGbzGFclcOUUTE8vVZrGOBDD2I08KC3+Ikmg4BOfz/O+MzgA2lJOWZoPyxVly6ebeGoqyi/cdR+AvwG7EP0/wzjdh5mbF8ZIoGFtPp+igOlNDqSQc/aodc9M= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712830243; c=relaxed/simple; bh=lFToQwuD0CN2lHHGhV5ThRLUedjbbjOz8kojfzH5ZY8=; h=Date:Message-ID:Mime-Version:From:To:Cc:Subject:Content-Type; b=RMr9OqfNpu/uLgS+wZJrbRPe6qV0lkEqwZiE7YJWFR5wgDx6UAaNw1CopavCGUNxOpUDhygsjmIKf1QecrPjzyP0ZcgSg1grLslJOI+gI1ejqqKhnNXH15RnSxbh732c0IOVABxNdFAHlkjwVGbLxaZKKKhcIUHngesWYvqwQYw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zte.com.cn; spf=pass smtp.mailfrom=zte.com.cn; arc=none smtp.client-ip=58.251.27.85 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=zte.com.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=zte.com.cn Received: from mxde.zte.com.cn (unknown [10.35.20.165]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mxct.zte.com.cn (FangMail) with ESMTPS id 4VFZxL1t7mzBmrW; Thu, 11 Apr 2024 18:02:14 +0800 (CST) Received: from mxhk.zte.com.cn (unknown [192.168.250.138]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mxde.zte.com.cn (FangMail) with ESMTPS id 4VFZxF0sXYz63t5D; Thu, 11 Apr 2024 18:02:09 +0800 (CST) Received: from mse-fl2.zte.com.cn (unknown [10.5.228.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mxhk.zte.com.cn (FangMail) with ESMTPS id 4VFZx42y5Nz6G42d; Thu, 11 Apr 2024 18:02:00 +0800 (CST) Received: from xaxapp03.zte.com.cn ([10.88.97.17]) by mse-fl2.zte.com.cn with SMTP id 43BA1qk5093269; Thu, 11 Apr 2024 18:01:52 +0800 (+08) (envelope-from xu.xin16@zte.com.cn) Received: from mapi (xaxapp02[null]) by mapi (Zmail) with MAPI id mid32; Thu, 11 Apr 2024 18:01:54 +0800 (CST) Date: Thu, 11 Apr 2024 18:01:54 +0800 (CST) X-Zmail-TransId: 2afa6617b512ffffffffdde-7c4e3 X-Mailer: Zmail v1.0 Message-ID: <20240411180154691lpBFKqpsU4tf1vugPPIqq@zte.com.cn> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 From: To: , , Cc: , , , , , , , , , , , , , , Subject: =?utf-8?q?=5BPATCH_net-next_v5=5D_net/ipv4=3A_add_tracepoint_for_ic?= =?utf-8?q?mp=5Fsend?= X-MAIL: mse-fl2.zte.com.cn 43BA1qk5093269 X-Fangmail-Anti-Spam-Filtered: true X-Fangmail-MID-QID: 6617B525.000/4VFZxL1t7mzBmrW From: hepeilin Introduce a tracepoint for icmp_send, which can help users to get more detail information conveniently when icmp abnormal events happen. 1. Giving an usecase example: ============================= When an application experiences packet loss due to an unreachable UDP destination port, the kernel will send an exception message through the icmp_send function. By adding a trace point for icmp_send, developers or system administrators can obtain detailed information about the UDP packet loss, including the type, code, source address, destination address, source port, and destination port. This facilitates the trouble-shooting of UDP packet loss issues especially for those network-service applications. 2. Operation Instructions: ========================== Switch to the tracing directory. cd /sys/kernel/tracing Filter for destination port unreachable. echo "type==3 && code==3" > events/icmp/icmp_send/filter Enable trace event. echo 1 > events/icmp/icmp_send/enable 3. Result View: ================ udp_client_erro-11370 [002] ...s.12 124.728002: icmp_send: icmp_send: type=3, code=3. From 127.0.0.1:41895 to 127.0.0.1:6666 ulen=23 skbaddr=00000000589b167a v4->v5: Some fixes according to https://lore.kernel.org/all/CAL+tcoDeXXh+zcRk4PHnUk8ELnx=CE2pcCqs7sFm0y9aK-Eehg@mail.gmail.com/ 1.Adjust the position of trace_icmp_send() to before icmp_push_reply(). v3->v4: Some fixes according to https://lore.kernel.org/all/CANn89i+EFEr7VHXNdOi59Ba_R1nFKSBJzBzkJFVgCTdXBx=YBg@mail.gmail.com/ 1.Add legality check for UDP header in SKB. 2.Target this patch for net-next. Changelog ======== v2->v3: Some fixes according to https://lore.kernel.org/all/20240319102549.7f7f6f53@gandalf.local.home/ 1. Change the tracking directory to/sys/kernel/tracking. 2. Adjust the layout of the TP-STRUCT_entry parameter structure. v1->v2: Some fixes according to https://lore.kernel.org/all/CANn89iL-y9e_VFpdw=sZtRnKRu_tnUwqHuFQTJvJsv-nz1xPDw@mail.gmail.com/ 1. adjust the trace_icmp_send() to more protocols than UDP. 2. move the calling of trace_icmp_send after sanity checks in __icmp_send(). Signed-off-by: Peilin He Reviewed-by: xu xin Reviewed-by: Yunkai Zhang Cc: Yang Yang Cc: Liu Chun Cc: Xuexin Jiang --- include/trace/events/icmp.h | 65 +++++++++++++++++++++++++++++++++++++ net/ipv4/icmp.c | 4 +++ 2 files changed, 69 insertions(+) create mode 100644 include/trace/events/icmp.h diff --git a/include/trace/events/icmp.h b/include/trace/events/icmp.h new file mode 100644 index 000000000..7d5190f48 --- /dev/null +++ b/include/trace/events/icmp.h @@ -0,0 +1,65 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM icmp + +#if !defined(_TRACE_ICMP_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_ICMP_H + +#include +#include + +TRACE_EVENT(icmp_send, + + TP_PROTO(const struct sk_buff *skb, int type, int code), + + TP_ARGS(skb, type, code), + + TP_STRUCT__entry( + __field(const void *, skbaddr) + __field(int, type) + __field(int, code) + __array(__u8, saddr, 4) + __array(__u8, daddr, 4) + __field(__u16, sport) + __field(__u16, dport) + __field(unsigned short, ulen) + ), + + TP_fast_assign( + struct iphdr *iph = ip_hdr(skb); + int proto_4 = iph->protocol; + __be32 *p32; + + __entry->skbaddr = skb; + __entry->type = type; + __entry->code = code; + + struct udphdr *uh = udp_hdr(skb); + if (proto_4 != IPPROTO_UDP || (u8 *)uh < skb->head || + (u8 *)uh + sizeof(struct udphdr) > skb_tail_pointer(skb)) { + __entry->sport = 0; + __entry->dport = 0; + __entry->ulen = 0; + } else { + __entry->sport = ntohs(uh->source); + __entry->dport = ntohs(uh->dest); + __entry->ulen = ntohs(uh->len); + } + + p32 = (__be32 *) __entry->saddr; + *p32 = iph->saddr; + + p32 = (__be32 *) __entry->daddr; + *p32 = iph->daddr; + ), + + TP_printk("icmp_send: type=%d, code=%d. From %pI4:%u to %pI4:%u ulen=%d skbaddr=%p", + __entry->type, __entry->code, + __entry->saddr, __entry->sport, __entry->daddr, + __entry->dport, __entry->ulen, __entry->skbaddr) +); + +#endif /* _TRACE_ICMP_H */ + +/* This part must be outside protection */ +#include \ No newline at end of file diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c index b71b836cc..2081fee18 100644 --- a/net/ipv4/icmp.c +++ b/net/ipv4/icmp.c @@ -92,6 +92,8 @@ #include #include #include +#define CREATE_TRACE_POINTS +#include /* * Build xmit assembly blocks @@ -766,6 +768,8 @@ void __icmp_send(struct sk_buff *skb_in, int type, int code, __be32 info, if (!fl4.saddr) fl4.saddr = htonl(INADDR_DUMMY); + trace_icmp_send(skb_in, type, code); + icmp_push_reply(&icmp_param, &fl4, &ipc, &rt); ende: ip_rt_put(rt);