| From foo@baz Fri Nov 7 11:36:50 PST 2014 |
| From: Li RongQing <roy.qing.li@gmail.com> |
| Date: Fri, 17 Oct 2014 16:53:23 +0800 |
| Subject: ipv4: fix a potential use after free in ip_tunnel_core.c |
| |
| From: Li RongQing <roy.qing.li@gmail.com> |
| |
| [ Upstream commit 1245dfc8cadb258386fcd27df38215a0eccb1f17 ] |
| |
| pskb_may_pull() maybe change skb->data and make eth pointer oboslete, |
| so set eth after pskb_may_pull() |
| |
| Fixes:3d7b46cd("ip_tunnel: push generic protocol handling to ip_tunnel module") |
| Cc: Pravin B Shelar <pshelar@nicira.com> |
| Signed-off-by: Li RongQing <roy.qing.li@gmail.com> |
| Acked-by: Pravin B Shelar <pshelar@nicira.com> |
| Signed-off-by: David S. Miller <davem@davemloft.net> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| net/ipv4/ip_tunnel_core.c | 3 ++- |
| 1 file changed, 2 insertions(+), 1 deletion(-) |
| |
| --- a/net/ipv4/ip_tunnel_core.c |
| +++ b/net/ipv4/ip_tunnel_core.c |
| @@ -91,11 +91,12 @@ int iptunnel_pull_header(struct sk_buff |
| skb_pull_rcsum(skb, hdr_len); |
| |
| if (inner_proto == htons(ETH_P_TEB)) { |
| - struct ethhdr *eh = (struct ethhdr *)skb->data; |
| + struct ethhdr *eh; |
| |
| if (unlikely(!pskb_may_pull(skb, ETH_HLEN))) |
| return -ENOMEM; |
| |
| + eh = (struct ethhdr *)skb->data; |
| if (likely(ntohs(eh->h_proto) >= ETH_P_802_3_MIN)) |
| skb->protocol = eh->h_proto; |
| else |
