This is a note to let you know that I've just added the patch titled
vti6: Don't report path MTU below IPV6_MIN_MTU.
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
vti6-don-t-report-path-mtu-below-ipv6_min_mtu.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Tue Dec 12 13:38:50 CET 2017
From: Steffen Klassert <steffen.klassert@xxxxxxxxxxx>
Date: Wed, 15 Feb 2017 11:38:58 +0100
Subject: vti6: Don't report path MTU below IPV6_MIN_MTU.
From: Steffen Klassert <steffen.klassert@xxxxxxxxxxx>
[ Upstream commit e3dc847a5f85b43ee2bfc8eae407a7e383483228 ]
In vti6_xmit(), the check for IPV6_MIN_MTU before we
send a ICMPV6_PKT_TOOBIG message is missing. So we might
report a PMTU below 1280. Fix this by adding the required
check.
Fixes: ccd740cbc6e ("vti6: Add pmtu handling to vti6_xmit.")
Signed-off-by: Steffen Klassert <steffen.klassert@xxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/ipv6/ip6_vti.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
--- a/net/ipv6/ip6_vti.c
+++ b/net/ipv6/ip6_vti.c
@@ -474,11 +474,15 @@ vti6_xmit(struct sk_buff *skb, struct ne
if (!skb->ignore_df && skb->len > mtu) {
skb_dst(skb)->ops->update_pmtu(dst, NULL, skb, mtu);
- if (skb->protocol == htons(ETH_P_IPV6))
+ if (skb->protocol == htons(ETH_P_IPV6)) {
+ if (mtu < IPV6_MIN_MTU)
+ mtu = IPV6_MIN_MTU;
+
icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
- else
+ } else {
icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED,
htonl(mtu));
+ }
return -EMSGSIZE;
}
Patches currently in stable-queue which might be from steffen.klassert@xxxxxxxxxxx are
queue-4.4/xfrm-copy-policy-family-in-clone_policy.patch
queue-4.4/vti6-don-t-report-path-mtu-below-ipv6_min_mtu.patch