net/mlx5e: Rx, Check ip headers sanity

In the two places is_last_ethertype_ip is being called, the caller will
be looking inside the ip header, to be safe, add ip{4,6} header sanity
check. And return true only on valid ip headers, i.e: the whole header
is contained in the linear part of the skb.

Note: Such situation is very rare and hard to reproduce, since mlx5e
allocates a large enough headroom to contain the largest header one can
imagine.

Fixes: 575c4738bc77 ("net/mlx5e: don't set CHECKSUM_COMPLETE on SCTP packets")
Reported-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
index 0e254de23f3d7310e429fa1591a69d75a1f4ec3a..36fd628188bc0e5eec13ea2d812ce5aa160503bb 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
@@ -692,7 +692,14 @@ static inline bool is_last_ethertype_ip(struct sk_buff *skb, int *network_depth,
 {
        *proto = ((struct ethhdr *)skb->data)->h_proto;
        *proto = __vlan_get_protocol(skb, *proto, network_depth);
-       return (*proto == htons(ETH_P_IP) || *proto == htons(ETH_P_IPV6));
+
+       if (*proto == htons(ETH_P_IP))
+               return pskb_may_pull(skb, *network_depth + sizeof(struct iphdr));
+
+       if (*proto == htons(ETH_P_IPV6))
+               return pskb_may_pull(skb, *network_depth + sizeof(struct ipv6hdr));
+
+       return false;
 }
 
 static inline void mlx5e_enable_ecn(struct mlx5e_rq *rq, struct sk_buff *skb)