From: Xin Long <lucien.xin@xxxxxxxxx>
When checking Hop-by-hop option header, if the option data is in
nonlinear area, it should do pskb_may_pull instead of discarding
the skb as a bad IPv6 packet.
Signed-off-by: Xin Long <lucien.xin@xxxxxxxxx>
Reviewed-by: Simon Horman <simon.horman@xxxxxxxxxxxx>
Acked-by: Nikolay Aleksandrov <razor@xxxxxxxxxxxxx>
Reviewed-by: Aaron Conole <aconole@xxxxxxxxxx>
Signed-off-by: Florian Westphal <fw@xxxxxxxxx>
---
net/bridge/br_netfilter_ipv6.c | 14 +++++++++-----
1 file changed, 9 insertions(+), 5 deletions(-)
diff --git a/net/bridge/br_netfilter_ipv6.c b/net/bridge/br_netfilter_ipv6.c
index 6b07f30675bb..afd1c718b683 100644
--- a/net/bridge/br_netfilter_ipv6.c
+++ b/net/bridge/br_netfilter_ipv6.c
@@ -45,14 +45,18 @@
*/
static int br_nf_check_hbh_len(struct sk_buff *skb)
{
- unsigned char *raw = (u8 *)(ipv6_hdr(skb) + 1);
+ int len, off = sizeof(struct ipv6hdr);
+ unsigned char *nh;
u32 pkt_len;
- const unsigned char *nh = skb_network_header(skb);
- int off = raw - nh;
- int len = (raw[1] + 1) << 3;
- if ((raw + len) - skb->data > skb_headlen(skb))
+ if (!pskb_may_pull(skb, off + 8))
goto bad;
+ nh = (unsigned char *)(ipv6_hdr(skb) + 1);
+ len = (nh[1] + 1) << 3;
+
+ if (!pskb_may_pull(skb, off + len))
+ goto bad;
+ nh = skb_network_header(skb);
off += 2;
len -= 2;
--
2.39.2
