lkml.org 
[lkml]   [2017]   [Dec]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v3,net-next] ip6_gre: fix a pontential issue in ip6erspan_rcv
Date
pskb_may_pull() can change skb->data, so we need to load ipv6h/ershdr at
the right place.

Fixes: 5a963eb61b7c ("ip6_gre: Add ERSPAN native tunnel support")
Cc: William Tu <u9012063@gmail.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>

---
Change since v3:
* Rebase on latest master branch.
* Fix wrong commit information.
---
net/ipv6/ip6_gre.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c
index 87b9892..9bd1103 100644
--- a/net/ipv6/ip6_gre.c
+++ b/net/ipv6/ip6_gre.c
@@ -507,12 +507,11 @@ static int ip6erspan_rcv(struct sk_buff *skb, int gre_hdr_len,
struct ip6_tnl *tunnel;
u8 ver;

- ipv6h = ipv6_hdr(skb);
- ershdr = (struct erspan_base_hdr *)skb->data;
-
if (unlikely(!pskb_may_pull(skb, sizeof(*ershdr))))
return PACKET_REJECT;

+ ipv6h = ipv6_hdr(skb);
+ ershdr = (struct erspan_base_hdr *)skb->data;
ver = (ntohs(ershdr->ver_vlan) & VER_MASK) >> VER_OFFSET;
tpi->key = cpu_to_be32(ntohs(ershdr->session_id) & ID_MASK);

--
1.8.3.1


\
 
 \ /
  Last update: 2017-12-20 02:54    [W:0.041 / U:3.768 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site