This is a note to let you know that I've just added the patch titled
ip6_tunnel: must reload ipv6h in ip6ip6_tnl_xmit()
to the 4.9-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:
ip6_tunnel-must-reload-ipv6h-in-ip6ip6_tnl_xmit.patch
and it can be found in the queue-4.9 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 Mon Jul 3 13:22:04 CEST 2017
From: Eric Dumazet <edumazet@xxxxxxxxxx>
Date: Mon, 23 Jan 2017 16:43:05 -0800
Subject: ip6_tunnel: must reload ipv6h in ip6ip6_tnl_xmit()
From: Eric Dumazet <edumazet@xxxxxxxxxx>
[ Upstream commit 21b995a9cb093fff33ec91d7cb3822b882a90a1e ]
Since ip6_tnl_parse_tlv_enc_lim() can call pskb_may_pull(),
we must reload any pointer that was related to skb->head
(or skb->data), or risk use after free.
Fixes: c12b395a4664 ("gre: Support GRE over IPv6")
Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Cc: Dmitry Kozlov <xeb@xxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/ipv6/ip6_gre.c | 3 +++
net/ipv6/ip6_tunnel.c | 2 ++
2 files changed, 5 insertions(+)
--- a/net/ipv6/ip6_gre.c
+++ b/net/ipv6/ip6_gre.c
@@ -582,6 +582,9 @@ static inline int ip6gre_xmit_ipv6(struc
return -1;
offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
+ /* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */
+ ipv6h = ipv6_hdr(skb);
+
if (offset > 0) {
struct ipv6_tlv_tnl_enc_lim *tel;
tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -1313,6 +1313,8 @@ ip6ip6_tnl_xmit(struct sk_buff *skb, str
fl6.flowlabel = key->label;
} else {
offset = ip6_tnl_parse_tlv_enc_lim(skb, skb_network_header(skb));
+ /* ip6_tnl_parse_tlv_enc_lim() might have reallocated skb->head */
+ ipv6h = ipv6_hdr(skb);
if (offset > 0) {
struct ipv6_tlv_tnl_enc_lim *tel;
Patches currently in stable-queue which might be from edumazet@xxxxxxxxxx are
queue-4.9/ip6_tunnel-must-reload-ipv6h-in-ip6ip6_tnl_xmit.patch
queue-4.9/gianfar-do-not-reuse-pages-from-emergency-reserve.patch
queue-4.9/fix-an-intermittent-pr_emerg-warning-about-lo-becoming-free.patch
queue-4.9/netfilter-xt_tcpmss-add-more-sanity-tests-on-tcph-doff.patch
queue-4.9/ipv6-release-dst-on-error-in-ip6_dst_lookup_tail.patch
queue-4.9/igmp-acquire-pmc-lock-for-ip_mc_clear_src.patch