net/mlx5e: Rx, Check ip headers sanity

BugLink: https://bugs.launchpad.net/bugs/1847155
[ Upstream commit 0318a7b7fcad9765931146efa7ca3a034194737c ]

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: fe1dc069990c ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
index 341258b64ec105142d3b14315546e666f2c80908..6a3cb9e6aa57b7d6535307196f04c0dffb43f934 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
@@ -634,7 +634,14 @@ 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)