aboutsummaryrefslogtreecommitdiff
path: root/net/ipv4/ip_tunnel.c
diff options
context:
space:
mode:
authorSteffen Klassert <steffen.klassert@secunet.com>2013-10-01 11:33:59 +0200
committerDavid S. Miller <davem@davemloft.net>2013-10-01 12:42:16 -0400
commit3e08f4a72f689c6296d336c2aab4bddd60c93ae2 (patch)
tree726a51f17de026da0e7c0135f827d529a406fcfd /net/ipv4/ip_tunnel.c
parente024bdc051ab99eafb5dd9bad87e79afc27f8a44 (diff)
downloadlinux-stericsson-3e08f4a72f689c6296d336c2aab4bddd60c93ae2.tar.gz
ip_tunnel: Fix a memory corruption in ip_tunnel_xmit
We might extend the used aera of a skb beyond the total headroom when we install the ipip header. Fix this by calling skb_cow_head() unconditionally. Bug was introduced with commit c544193214 ("GRE: Refactor GRE tunneling code.") Cc: Pravin Shelar <pshelar@nicira.com> Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/ip_tunnel.c')
-rw-r--r--net/ipv4/ip_tunnel.c12
1 files changed, 6 insertions, 6 deletions
diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
index d3fbad422e0e..dfc6d8a3caa7 100644
--- a/net/ipv4/ip_tunnel.c
+++ b/net/ipv4/ip_tunnel.c
@@ -642,13 +642,13 @@ void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
max_headroom = LL_RESERVED_SPACE(rt->dst.dev) + sizeof(struct iphdr)
+ rt->dst.header_len;
- if (max_headroom > dev->needed_headroom) {
+ if (max_headroom > dev->needed_headroom)
dev->needed_headroom = max_headroom;
- if (skb_cow_head(skb, dev->needed_headroom)) {
- dev->stats.tx_dropped++;
- dev_kfree_skb(skb);
- return;
- }
+
+ if (skb_cow_head(skb, dev->needed_headroom)) {
+ dev->stats.tx_dropped++;
+ dev_kfree_skb(skb);
+ return;
}
err = iptunnel_xmit(rt, skb, fl4.saddr, fl4.daddr, protocol,