From 21cf377a9c40658777ecbd6242be449a19a84e44 Mon Sep 17 00:00:00 2001 From: Lino Sanfilippo Date: Wed, 21 Jul 2021 23:56:41 +0200 Subject: [PATCH 1/2] net: dsa: ensure linearized SKBs in case of tail taggers The function skb_put() that is used by tail taggers to make room for the DSA tag must only be called for linearized SKBS. However in case that the slave device inherited features like NETIF_F_HW_SG or NETIF_F_FRAGLIST the SKB passed to the slaves transmit function may not be linearized. Avoid those SKBs by clearing the NETIF_F_HW_SG and NETIF_F_FRAGLIST flags for tail taggers. Furthermore since the tagging protocol can be changed at runtime move the code for setting up the slaves features into dsa_slave_setup_tagger(). Suggested-by: Vladimir Oltean Signed-off-by: Lino Sanfilippo Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller --- net/dsa/slave.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) diff --git a/net/dsa/slave.c b/net/dsa/slave.c index ffbba1e71551..532085da8d8f 100644 --- a/net/dsa/slave.c +++ b/net/dsa/slave.c @@ -1808,6 +1808,7 @@ void dsa_slave_setup_tagger(struct net_device *slave) struct dsa_slave_priv *p = netdev_priv(slave); const struct dsa_port *cpu_dp = dp->cpu_dp; struct net_device *master = cpu_dp->master; + const struct dsa_switch *ds = dp->ds; slave->needed_headroom = cpu_dp->tag_ops->needed_headroom; slave->needed_tailroom = cpu_dp->tag_ops->needed_tailroom; @@ -1819,6 +1820,14 @@ void dsa_slave_setup_tagger(struct net_device *slave) slave->needed_tailroom += master->needed_tailroom; p->xmit = cpu_dp->tag_ops->xmit; + + slave->features = master->vlan_features | NETIF_F_HW_TC; + if (ds->ops->port_vlan_add && ds->ops->port_vlan_del) + slave->features |= NETIF_F_HW_VLAN_CTAG_FILTER; + slave->hw_features |= NETIF_F_HW_TC; + slave->features |= NETIF_F_LLTX; + if (slave->needed_tailroom) + slave->features &= ~(NETIF_F_SG | NETIF_F_FRAGLIST); } static struct lock_class_key dsa_slave_netdev_xmit_lock_key; @@ -1881,11 +1890,6 @@ int dsa_slave_create(struct dsa_port *port) if (slave_dev == NULL) return -ENOMEM; - slave_dev->features = master->vlan_features | NETIF_F_HW_TC; - if (ds->ops->port_vlan_add && ds->ops->port_vlan_del) - slave_dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER; - slave_dev->hw_features |= NETIF_F_HW_TC; - slave_dev->features |= NETIF_F_LLTX; slave_dev->ethtool_ops = &dsa_slave_ethtool_ops; if (!is_zero_ether_addr(port->mac)) ether_addr_copy(slave_dev->dev_addr, port->mac); From 37120f23ac8998c250573ea3247ff77426551f69 Mon Sep 17 00:00:00 2001 From: Lino Sanfilippo Date: Wed, 21 Jul 2021 23:56:42 +0200 Subject: [PATCH 2/2] net: dsa: tag_ksz: dont let the hardware process the layer 4 checksum If the checksum calculation is offloaded to the network device (e.g due to NETIF_F_HW_CSUM inherited from the DSA master device), the calculated layer 4 checksum is incorrect. This is since the DSA tag which is placed after the layer 4 data is considered as being part of the daa and thus errorneously included into the checksum calculation. To avoid this, always calculate the layer 4 checksum in software. Signed-off-by: Lino Sanfilippo Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller --- net/dsa/tag_ksz.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/net/dsa/tag_ksz.c b/net/dsa/tag_ksz.c index 53565f48934c..a201ccf2435d 100644 --- a/net/dsa/tag_ksz.c +++ b/net/dsa/tag_ksz.c @@ -53,6 +53,9 @@ static struct sk_buff *ksz8795_xmit(struct sk_buff *skb, struct net_device *dev) u8 *tag; u8 *addr; + if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb)) + return NULL; + /* Tag encoding */ tag = skb_put(skb, KSZ_INGRESS_TAG_LEN); addr = skb_mac_header(skb); @@ -114,6 +117,9 @@ static struct sk_buff *ksz9477_xmit(struct sk_buff *skb, u8 *addr; u16 val; + if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb)) + return NULL; + /* Tag encoding */ tag = skb_put(skb, KSZ9477_INGRESS_TAG_LEN); addr = skb_mac_header(skb); @@ -164,6 +170,9 @@ static struct sk_buff *ksz9893_xmit(struct sk_buff *skb, u8 *addr; u8 *tag; + if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb)) + return NULL; + /* Tag encoding */ tag = skb_put(skb, KSZ_INGRESS_TAG_LEN); addr = skb_mac_header(skb);