From: jeffreyji <[email protected]>
Increment rx_otherhost_dropped counter when packet dropped due to
mismatched dest MAC addr.
An example when this drop can occur is when manually crafting raw
packets that will be consumed by a user space application via a tap
device. For testing purposes local traffic was generated using trafgen
for the client and netcat to start a server
Tested: Created 2 netns, sent 1 packet using trafgen from 1 to the other
with "{eth(daddr=$INCORRECT_MAC...}", verified that iproute2 showed the
counter was incremented. (Also had to modify iproute2 to show the stat,
additional patch for that coming next.)
Signed-off-by: jeffreyji <[email protected]>
---
include/linux/netdevice.h | 1 +
include/uapi/linux/if_link.h | 5 +++++
net/core/dev.c | 2 ++
net/ipv4/ip_input.c | 1 +
net/ipv6/ip6_input.c | 1 +
5 files changed, 10 insertions(+)
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index c79ee2296296..96c2030f4c1f 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -2025,6 +2025,7 @@ struct net_device {
atomic_long_t rx_dropped;
atomic_long_t tx_dropped;
atomic_long_t rx_nohandler;
+ atomic_long_t rx_otherhost_dropped;
/* Stats to monitor link on/off, flapping */
atomic_t carrier_up_count;
diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index be09d2ad4b5d..834382317889 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -211,6 +211,9 @@ struct rtnl_link_stats {
* @rx_nohandler: Number of packets received on the interface
* but dropped by the networking stack because the device is
* not designated to receive packets (e.g. backup link in a bond).
+ *
+ * @rx_otherhost_dropped: Number of packets dropped due to mismatch in
+ * packet's destination MAC address.
*/
struct rtnl_link_stats64 {
__u64 rx_packets;
@@ -243,6 +246,8 @@ struct rtnl_link_stats64 {
__u64 rx_compressed;
__u64 tx_compressed;
__u64 rx_nohandler;
+
+ __u64 rx_otherhost_dropped;
};
/* The struct should be in sync with struct ifmap */
diff --git a/net/core/dev.c b/net/core/dev.c
index 2d6771075720..d039d8fdc16a 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -10037,6 +10037,8 @@ struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
storage->rx_dropped += (unsigned long)atomic_long_read(&dev->rx_dropped);
storage->tx_dropped += (unsigned long)atomic_long_read(&dev->tx_dropped);
storage->rx_nohandler += (unsigned long)atomic_long_read(&dev->rx_nohandler);
+ storage->rx_otherhost_dropped +=
+ (unsigned long)atomic_long_read(&dev->rx_otherhost_dropped);
return storage;
}
EXPORT_SYMBOL(dev_get_stats);
diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c
index d94f9f7e60c3..ef97b0a4c77f 100644
--- a/net/ipv4/ip_input.c
+++ b/net/ipv4/ip_input.c
@@ -450,6 +450,7 @@ static struct sk_buff *ip_rcv_core(struct sk_buff *skb, struct net *net)
* that it receives, do not try to analyse it.
*/
if (skb->pkt_type == PACKET_OTHERHOST) {
+ atomic_long_inc(&skb->dev->rx_otherhost_dropped);
drop_reason = SKB_DROP_REASON_OTHERHOST;
goto drop;
}
diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c
index d4b1e2c5aa76..3f0cbe126d82 100644
--- a/net/ipv6/ip6_input.c
+++ b/net/ipv6/ip6_input.c
@@ -150,6 +150,7 @@ static struct sk_buff *ip6_rcv_core(struct sk_buff *skb, struct net_device *dev,
struct inet6_dev *idev;
if (skb->pkt_type == PACKET_OTHERHOST) {
+ atomic_long_inc(&skb->dev->rx_otherhost_dropped);
kfree_skb(skb);
return NULL;
}
--
2.35.1.574.g5d30c73bfb-goog
Hey Jeffrey,
Looking at it in patchwork
(https://patchwork.kernel.org/project/netdevbpf/patch/[email protected]/),
it is complaining about kdoc.
Seems that you're missing the kdoc comment about rx_otherhost_dropped
in the include/linux/netdevice.h file, other than that LGTM.
On Mon, Feb 28, 2022 at 4:12 PM Jeffrey Ji <[email protected]> wrote:
>
> From: jeffreyji <[email protected]>
>
> Increment rx_otherhost_dropped counter when packet dropped due to
> mismatched dest MAC addr.
>
> An example when this drop can occur is when manually crafting raw
> packets that will be consumed by a user space application via a tap
> device. For testing purposes local traffic was generated using trafgen
> for the client and netcat to start a server
>
> Tested: Created 2 netns, sent 1 packet using trafgen from 1 to the other
> with "{eth(daddr=$INCORRECT_MAC...}", verified that iproute2 showed the
> counter was incremented. (Also had to modify iproute2 to show the stat,
> additional patch for that coming next.)
>
> Signed-off-by: jeffreyji <[email protected]>
> ---
> include/linux/netdevice.h | 1 +
> include/uapi/linux/if_link.h | 5 +++++
> net/core/dev.c | 2 ++
> net/ipv4/ip_input.c | 1 +
> net/ipv6/ip6_input.c | 1 +
> 5 files changed, 10 insertions(+)
>
> diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
> index c79ee2296296..96c2030f4c1f 100644
> --- a/include/linux/netdevice.h
> +++ b/include/linux/netdevice.h
> @@ -2025,6 +2025,7 @@ struct net_device {
> atomic_long_t rx_dropped;
> atomic_long_t tx_dropped;
> atomic_long_t rx_nohandler;
> + atomic_long_t rx_otherhost_dropped;
>
> /* Stats to monitor link on/off, flapping */
> atomic_t carrier_up_count;
> diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
> index be09d2ad4b5d..834382317889 100644
> --- a/include/uapi/linux/if_link.h
> +++ b/include/uapi/linux/if_link.h
> @@ -211,6 +211,9 @@ struct rtnl_link_stats {
> * @rx_nohandler: Number of packets received on the interface
> * but dropped by the networking stack because the device is
> * not designated to receive packets (e.g. backup link in a bond).
> + *
> + * @rx_otherhost_dropped: Number of packets dropped due to mismatch in
> + * packet's destination MAC address.
> */
> struct rtnl_link_stats64 {
> __u64 rx_packets;
> @@ -243,6 +246,8 @@ struct rtnl_link_stats64 {
> __u64 rx_compressed;
> __u64 tx_compressed;
> __u64 rx_nohandler;
> +
> + __u64 rx_otherhost_dropped;
> };
>
> /* The struct should be in sync with struct ifmap */
> diff --git a/net/core/dev.c b/net/core/dev.c
> index 2d6771075720..d039d8fdc16a 100644
> --- a/net/core/dev.c
> +++ b/net/core/dev.c
> @@ -10037,6 +10037,8 @@ struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
> storage->rx_dropped += (unsigned long)atomic_long_read(&dev->rx_dropped);
> storage->tx_dropped += (unsigned long)atomic_long_read(&dev->tx_dropped);
> storage->rx_nohandler += (unsigned long)atomic_long_read(&dev->rx_nohandler);
> + storage->rx_otherhost_dropped +=
> + (unsigned long)atomic_long_read(&dev->rx_otherhost_dropped);
> return storage;
> }
> EXPORT_SYMBOL(dev_get_stats);
> diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c
> index d94f9f7e60c3..ef97b0a4c77f 100644
> --- a/net/ipv4/ip_input.c
> +++ b/net/ipv4/ip_input.c
> @@ -450,6 +450,7 @@ static struct sk_buff *ip_rcv_core(struct sk_buff *skb, struct net *net)
> * that it receives, do not try to analyse it.
> */
> if (skb->pkt_type == PACKET_OTHERHOST) {
> + atomic_long_inc(&skb->dev->rx_otherhost_dropped);
> drop_reason = SKB_DROP_REASON_OTHERHOST;
> goto drop;
> }
> diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c
> index d4b1e2c5aa76..3f0cbe126d82 100644
> --- a/net/ipv6/ip6_input.c
> +++ b/net/ipv6/ip6_input.c
> @@ -150,6 +150,7 @@ static struct sk_buff *ip6_rcv_core(struct sk_buff *skb, struct net_device *dev,
> struct inet6_dev *idev;
>
> if (skb->pkt_type == PACKET_OTHERHOST) {
> + atomic_long_inc(&skb->dev->rx_otherhost_dropped);
> kfree_skb(skb);
> return NULL;
> }
> --
> 2.35.1.574.g5d30c73bfb-goog
>