diff options
| author | Paolo Abeni <pabeni@redhat.com> | 2018-09-24 15:48:19 +0200 |
|---|---|---|
| committer | Moyster <oysterized@gmail.com> | 2019-05-03 19:24:03 +0200 |
| commit | 15bb1d39066d670d126224bb09f40f66d6935c0e (patch) | |
| tree | 8ad549d5b9a7c8644acba5df86fbbee1d15e2430 /net/ipv4 | |
| parent | 74e89fdb9d6d4dba2db651b060bd58fc5df1f85e (diff) | |
ip_tunnel: be careful when accessing the inner header
commit ccfec9e5cb2d48df5a955b7bf47f7782157d3bc2 upstream.
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.")
Change-Id: I6b15e17962ffa2cc6c2d0715a6172b7f8e99e9bc
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: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'net/ipv4')
| -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 aee92dbd1..7150b4c8b 100644 --- a/net/ipv4/ip_tunnel.c +++ b/net/ipv4/ip_tunnel.c @@ -542,6 +542,7 @@ void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, const struct iphdr *tnl_params) { struct ip_tunnel *tunnel = netdev_priv(dev); + unsigned int inner_nhdr_len = 0; const struct iphdr *inner_iph; struct iphdr *iph; struct flowi4 fl4; @@ -552,6 +553,14 @@ void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, unsigned int max_headroom; /* The extra header space needed */ __be32 dst; + /* 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); memset(IPCB(skb), 0, sizeof(*IPCB(skb))); |