netdev - [PATCH net-next 2/2] net-next: copy user configured flowlabel to reset packet

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: Windows password security audit tool. GUI, reports in PDF.

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

Date:   Fri, 17 Nov 2017 10:24:51 -0800
From:   Shaohua Li <shli@...nel.org>
To:     netdev@...r.kernel.org, davem@...emloft.net
Cc:     kafai@...com, eric.dumazet@...il.com, flo@...rcot.fr,
        xiyou.wangcong@...il.com, tom@...bertland.com,
        Kernel Team <Kernel-team@...com>, Shaohua Li <shli@...com>
Subject: [PATCH net-next 2/2] net-next: copy user configured flowlabel to reset packet

From: Shaohua Li <shli@...com>

Reset packet doesn't use user configured flowlabel, instead, it always
uses 0. This will cause inconsistency for flowlabel. tw sock already
records flowlabel info, so we can directly use it.

Cc: Martin KaFai Lau <kafai@...com>
Cc: Eric Dumazet <eric.dumazet@...il.com>
Cc: Florent Fourcot <flo@...rcot.fr>
Cc: Cong Wang <xiyou.wangcong@...il.com>
Cc: Tom Herbert <tom@...bertland.com>
Signed-off-by: Shaohua Li <shli@...com>
---
 net/ipv6/tcp_ipv6.c | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index a1a5802..9b678cd 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -901,6 +901,8 @@ static void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb)
 	struct sock *sk1 = NULL;
 #endif
 	int oif = 0;
+	u8 tclass = 0;
+	__be32 flowlabel = 0;
 
 	if (th->rst)
 		return;
@@ -954,7 +956,21 @@ static void tcp_v6_send_reset(const struct sock *sk, struct sk_buff *skb)
 		trace_tcp_send_reset(sk, skb);
 	}
 
-	tcp_v6_send_response(sk, skb, seq, ack_seq, 0, 0, 0, oif, key, 1, 0, 0);
+	if (sk) {
+		if (sk_fullsock(sk)) {
+			struct ipv6_pinfo *np = inet6_sk(sk);
+
+			tclass = np->tclass;
+			flowlabel = np->flow_label & IPV6_FLOWLABEL_MASK;
+		} else {
+			struct inet_timewait_sock *tw = inet_twsk(sk);
+
+			tclass = tw->tw_tclass;
+			flowlabel = cpu_to_be32(tw->tw_flowlabel);
+		}
+	}
+	tcp_v6_send_response(sk, skb, seq, ack_seq, 0, 0, 0, oif, key, 1,
+		tclass, flowlabel);
 
 #ifdef CONFIG_TCP_MD5SIG
 out:
-- 
2.9.5