linux-kernel - [PATCH net-next] tcp: use data length instead of skb->len in tcp

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 24 May 2018 20:48:17 +0800
From:   Yafang Shao <laoar.shao@...il.com>
To:     davem@...emloft.net, songliubraving@...com
Cc:     netdev@...r.kernel.org, linux-kernel@...r.kernel.org,
        Yafang Shao <laoar.shao@...il.com>
Subject: [PATCH net-next] tcp: use data length instead of skb->len in tcp_probe

skb->len is meaningless to user.
data length could be more helpful, with which we can easily filter out
the packet without payload.

Signed-off-by: Yafang Shao <laoar.shao@...il.com>
---
 include/trace/events/tcp.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/trace/events/tcp.h b/include/trace/events/tcp.h
index c1a5284..259b991 100644
--- a/include/trace/events/tcp.h
+++ b/include/trace/events/tcp.h
@@ -261,7 +261,7 @@
 		__entry->dport = ntohs(inet->inet_dport);
 		__entry->mark = skb->mark;
 
-		__entry->length = skb->len;
+		__entry->length = skb->len - tcp_hdrlen(skb);
 		__entry->snd_nxt = tp->snd_nxt;
 		__entry->snd_una = tp->snd_una;
 		__entry->snd_cwnd = tp->snd_cwnd;
@@ -272,7 +272,7 @@
 		__entry->sock_cookie = sock_gen_cookie(sk);
 	),
 
-	TP_printk("src=%pISpc dest=%pISpc mark=%#x length=%d snd_nxt=%#x snd_una=%#x snd_cwnd=%u ssthresh=%u snd_wnd=%u srtt=%u rcv_wnd=%u sock_cookie=%llx",
+	TP_printk("src=%pISpc dest=%pISpc mark=%#x data_len=%d snd_nxt=%#x snd_una=%#x snd_cwnd=%u ssthresh=%u snd_wnd=%u srtt=%u rcv_wnd=%u sock_cookie=%llx",
 		  __entry->saddr, __entry->daddr, __entry->mark,
 		  __entry->length, __entry->snd_nxt, __entry->snd_una,
 		  __entry->snd_cwnd, __entry->ssthresh, __entry->snd_wnd,
-- 
1.8.3.1