diff options
| author | Paolo Abeni <pabeni@redhat.com> | 2018-09-24 15:48:19 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-10-20 09:52:36 +0200 |
| commit | f9d3572816ba724129da0ec2ecd590d5c899e86e (patch) | |
| tree | 382b38a9147eb3f5042571d174bdd00d46450dd8 | |
| parent | 20f16d1a3817523350e9c5b5a231c4cb2cf0ab3f (diff) | |
ip_tunnel: be careful when accessing the inner header
[ Upstream commit ccfec9e5cb2d48df5a955b7bf47f7782157d3bc2]
Cong noted that we need the same checks introduced by commit 76c0ddd8c3a6
("ip6_tunnel: be careful when accessing the inner header")
even for ipv4 tunnels.
Fixes: c54419321455 ("GRE: Refactor GRE tunneling code.")
Suggested-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | net/ipv4/ip_tunnel.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c index 3d62feb65932..9d3176b080a4 100644 --- a/net/ipv4/ip_tunnel.c +++ b/net/ipv4/ip_tunnel.c @@ -597,6 +597,7 @@ void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, const struct iphdr *tnl_params, u8 protocol) { struct ip_tunnel *tunnel = netdev_priv(dev); + unsigned int inner_nhdr_len = 0; const struct iphdr *inner_iph; struct flowi4 fl4; u8 tos, ttl; @@ -607,6 +608,14 @@ void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, int err; bool connected; + /* ensure we can access the inner net header, for several users below */ + if (skb->protocol == htons(ETH_P_IP)) + inner_nhdr_len = sizeof(struct iphdr); + else if (skb->protocol == htons(ETH_P_IPV6)) + inner_nhdr_len = sizeof(struct ipv6hdr); + if (unlikely(!pskb_may_pull(skb, inner_nhdr_len))) + goto tx_error; + inner_iph = (const struct iphdr *)skb_inner_network_header(skb); connected = (tunnel->parms.iph.daddr != 0); |