[PATCH 4.12 30/52] net/mlx5e: Fix inline header size for small packets

From: Greg Kroah-Hartman
Date: Mon Sep 18 2017 - 05:13:53 EST


4.12-stable review patch. If anyone has any objections, please let me know.

------------------

From: Moshe Shemesh <moshe@xxxxxxxxxxxx>


[ Upstream commit 6aace17e64f4aa1c49802c46bd10688968b3787f ]

Fix inline header size, make sure it is not greater than skb len.
This bug effects small packets, for example L2 packets with size < 18.

Fixes: ae76715d153e ("net/mlx5e: Check the minimum inline header mode before xmit")
Signed-off-by: Moshe Shemesh <moshe@xxxxxxxxxxxx>
Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/mellanox/mlx5/core/en_tx.c | 17 ++++++++++-------
1 file changed, 10 insertions(+), 7 deletions(-)

--- a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
@@ -127,10 +127,10 @@ static inline int mlx5e_skb_l3_header_of
return mlx5e_skb_l2_header_offset(skb);
}

-static inline unsigned int mlx5e_calc_min_inline(enum mlx5_inline_modes mode,
- struct sk_buff *skb)
+static inline u16 mlx5e_calc_min_inline(enum mlx5_inline_modes mode,
+ struct sk_buff *skb)
{
- int hlen;
+ u16 hlen;

switch (mode) {
case MLX5_INLINE_MODE_NONE:
@@ -139,19 +139,22 @@ static inline unsigned int mlx5e_calc_mi
hlen = eth_get_headlen(skb->data, skb_headlen(skb));
if (hlen == ETH_HLEN && !skb_vlan_tag_present(skb))
hlen += VLAN_HLEN;
- return hlen;
+ break;
case MLX5_INLINE_MODE_IP:
/* When transport header is set to zero, it means no transport
* header. When transport header is set to 0xff's, it means
* transport header wasn't set.
*/
- if (skb_transport_offset(skb))
- return mlx5e_skb_l3_header_offset(skb);
+ if (skb_transport_offset(skb)) {
+ hlen = mlx5e_skb_l3_header_offset(skb);
+ break;
+ }
/* fall through */
case MLX5_INLINE_MODE_L2:
default:
- return mlx5e_skb_l2_header_offset(skb);
+ hlen = mlx5e_skb_l2_header_offset(skb);
}
+ return min_t(u16, hlen, skb->len);
}

static inline void mlx5e_tx_skb_pull_inline(unsigned char **skb_data,