[PATCH 4.9 241/271] net: usb: lan78xx: Add .ndo_features_check

From: Greg Kroah-Hartman
Date: Tue Jan 28 2020 - 09:33:55 EST


From: James Hughes <james.hughes@xxxxxxxxxxxxxxx>

[ Upstream commit ce896476c65d72b4b99fa09c2f33436b4198f034 ]

As reported by Eric Dumazet, there are still some outstanding
cases where the driver does not handle TSO correctly when skb's
are over a certain size. Most cases have been fixed, this patch
should ensure that forwarded SKB's that are greater than
MAX_SINGLE_PACKET_SIZE - TX_OVERHEAD are software segmented
and handled correctly.

Signed-off-by: James Hughes <james.hughes@xxxxxxxxxxxxxxx>
Reviewed-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/usb/lan78xx.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)

--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c
@@ -30,6 +30,7 @@
#include <linux/ipv6.h>
#include <linux/mdio.h>
#include <net/ip6_checksum.h>
+#include <net/vxlan.h>
#include <linux/microchipphy.h>
#include <linux/of_net.h>
#include "lan78xx.h"
@@ -3291,6 +3292,19 @@ static void lan78xx_tx_timeout(struct ne
tasklet_schedule(&dev->bh);
}

+static netdev_features_t lan78xx_features_check(struct sk_buff *skb,
+ struct net_device *netdev,
+ netdev_features_t features)
+{
+ if (skb->len + TX_OVERHEAD > MAX_SINGLE_PACKET_SIZE)
+ features &= ~NETIF_F_GSO_MASK;
+
+ features = vlan_features_check(skb, features);
+ features = vxlan_features_check(skb, features);
+
+ return features;
+}
+
static const struct net_device_ops lan78xx_netdev_ops = {
.ndo_open = lan78xx_open,
.ndo_stop = lan78xx_stop,
@@ -3304,6 +3318,7 @@ static const struct net_device_ops lan78
.ndo_set_features = lan78xx_set_features,
.ndo_vlan_rx_add_vid = lan78xx_vlan_rx_add_vid,
.ndo_vlan_rx_kill_vid = lan78xx_vlan_rx_kill_vid,
+ .ndo_features_check = lan78xx_features_check,
};

static void lan78xx_stat_monitor(unsigned long param)