[116/126] ipv6/tcp: Stop processing ICMPv6 redirect messages

Steven Rostedt
2013-05-07T04:42:53Z

[-- Attachment #1: 0116-ipv6-tcp-Stop-processing-ICMPv6-redirect-messages.patch --]
[-- Type: text/plain, Size: 1636 bytes --]

3.6.11.3 stable review patch.
If anyone has any objections, please let me know.

------------------

From: Christoph Paasch <christoph.paasch@uclouvain.be>

[ Upstream commit 50a75a8914539c5dcd441c5f54d237a666a426fd ]

Tetja Rediske found that if the host receives an ICMPv6 redirect message
after sending a SYN+ACK, the connection will be reset.

He bisected it down to 093d04d (ipv6: Change skb->data before using
icmpv6_notify() to propagate redirect), but the origin of the bug comes
from ec18d9a26 (ipv6: Add redirect support to all protocol icmp error
handlers.). The bug simply did not trigger prior to 093d04d, because
skb->data did not point to the inner IP header and thus icmpv6_notify
did not call the correct err_handler.

This patch adds the missing "goto out;" in tcp_v6_err. After receiving
an ICMPv6 Redirect, we should not continue processing the ICMP in
tcp_v6_err, as this may trigger the removal of request-socks or setting
sk_err(_soft).

Reported-by: Tetja Rediske <tetja@tetja.de>
Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
net/ipv6/tcp_ipv6.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index fe48fc9..e3eec75 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -397,6 +397,7 @@ static void tcp_v6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,

if (dst)
dst->ops->redirect(dst, sk, skb);
+ goto out;
}

if (type == ICMPV6_PKT_TOOBIG) {
--
1.7.10.4