6.6-stable review patch. If anyone has any objections, please let me know.
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From: Peilin He he.peilin@zte.com.cn
[ Upstream commit db3efdcf70c752e8a8deb16071d8e693c3ef8746 ]
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
Signed-off-by: Peilin He he.peilin@zte.com.cn Signed-off-by: xu xin xu.xin16@zte.com.cn Reviewed-by: Yunkai Zhang zhang.yunkai@zte.com.cn Cc: Yang Yang yang.yang29@zte.com.cn Cc: Liu Chun liu.chun2@zte.com.cn Cc: Xuexin Jiang jiang.xuexin@zte.com.cn Reviewed-by: Steven Rostedt (Google) rostedt@goodmis.org Signed-off-by: David S. Miller davem@davemloft.net Stable-dep-of: 27843ce6ba3d ("ipvlan: ensure network headers are in skb linear part") Signed-off-by: Sasha Levin sashal@kernel.org --- include/trace/events/icmp.h | 67 +++++++++++++++++++++++++++++++++++++ net/ipv4/icmp.c | 4 +++ 2 files changed, 71 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 0000000000000..31559796949a7 --- /dev/null +++ b/include/trace/events/icmp.h @@ -0,0 +1,67 @@ +/* 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 <linux/icmp.h> +#include <linux/tracepoint.h> + +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); + struct udphdr *uh = udp_hdr(skb); + int proto_4 = iph->protocol; + __be32 *p32; + + __entry->skbaddr = skb; + __entry->type = type; + __entry->code = code; + + 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 <trace/define_trace.h> + diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c index a21d32b3ae6c3..b05fa424ad5ce 100644 --- a/net/ipv4/icmp.c +++ b/net/ipv4/icmp.c @@ -93,6 +93,8 @@ #include <net/ip_fib.h> #include <net/l3mdev.h> #include <net/addrconf.h> +#define CREATE_TRACE_POINTS +#include <trace/events/icmp.h>
/* * Build xmit assembly blocks @@ -778,6 +780,8 @@ 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(sk, &icmp_param, &fl4, &ipc, &rt); ende: ip_rt_put(rt);