In this commit, we make ip_mkroute_input() and __mkroute_input() return
drop reasons.
The drop reason "SKB_DROP_REASON_ARP_PVLAN_DISABLE" is introduced for
the case: the packet which is not IP is forwarded to the in_dev, and
the proxy_arp_pvlan is not enabled.
Signed-off-by: Menglong Dong <dongml2@xxxxxxxxxxxxxxx>
---
This name "SKB_DROP_REASON_ARP_PVLAN_DISABLE" is ugly, and I have not
figured out a suitable name for this case yet :/
v5:
- delete the unneeded comment in __mkroute_input()
---
include/net/dropreason-core.h | 7 +++++++
net/ipv4/route.c | 34 ++++++++++++++++++----------------
2 files changed, 25 insertions(+), 16 deletions(-)
diff --git a/include/net/dropreason-core.h b/include/net/dropreason-core.h
index 74624d369d48..6c5a1ea209a2 100644
--- a/include/net/dropreason-core.h
+++ b/include/net/dropreason-core.h
@@ -104,6 +104,7 @@
FN(IP_TUNNEL_ECN) \
FN(TUNNEL_TXINFO) \
FN(LOCAL_MAC) \
+ FN(ARP_PVLAN_DISABLE) \
FNe(MAX)
/**
@@ -477,6 +478,12 @@ enum skb_drop_reason {
* the MAC address of the local netdev.
*/
SKB_DROP_REASON_LOCAL_MAC,
+ /**
+ * @SKB_DROP_REASON_ARP_PVLAN_DISABLE: packet which is not IP is
+ * forwarded to the in_dev, and the proxy_arp_pvlan is not
+ * enabled.
+ */
+ SKB_DROP_REASON_ARP_PVLAN_DISABLE,
/**
* @SKB_DROP_REASON_MAX: the maximum of core drop reasons, which
* shouldn't be used as a real 'reason' - only for tracing code gen
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index ce1201dbf464..5061a935ce62 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1769,10 +1769,12 @@ static void ip_handle_martian_source(struct net_device *dev,
}
/* called in rcu_read_lock() section */
-static int __mkroute_input(struct sk_buff *skb, const struct fib_result *res,
- struct in_device *in_dev, __be32 daddr,
- __be32 saddr, dscp_t dscp)
+static enum skb_drop_reason
+__mkroute_input(struct sk_buff *skb, const struct fib_result *res,
+ struct in_device *in_dev, __be32 daddr,
+ __be32 saddr, dscp_t dscp)
{
+ enum skb_drop_reason reason = SKB_DROP_REASON_NOT_SPECIFIED;
struct fib_nh_common *nhc = FIB_RES_NHC(*res);
struct net_device *dev = nhc->nhc_dev;
struct fib_nh_exception *fnhe;
@@ -1786,13 +1788,13 @@ static int __mkroute_input(struct sk_buff *skb, const struct fib_result *res,
out_dev = __in_dev_get_rcu(dev);
if (!out_dev) {
net_crit_ratelimited("Bug in ip_route_input_slow(). Please report.\n");
- return -EINVAL;
+ return reason;
}
err = fib_validate_source(skb, saddr, daddr, dscp, FIB_RES_OIF(*res),
in_dev->dev, in_dev, &itag);
if (err < 0) {
- err = -EINVAL;
+ reason = -err;
ip_handle_martian_source(in_dev->dev, in_dev, skb, daddr,
saddr);
@@ -1820,7 +1822,7 @@ static int __mkroute_input(struct sk_buff *skb, const struct fib_result *res,
*/
if (out_dev == in_dev &&
IN_DEV_PROXY_ARP_PVLAN(in_dev) == 0) {
- err = -EINVAL;
+ reason = SKB_DROP_REASON_ARP_PVLAN_DISABLE;
goto cleanup;
}
}
@@ -1843,7 +1845,7 @@ static int __mkroute_input(struct sk_buff *skb, const struct fib_result *res,
rth = rt_dst_alloc(out_dev->dev, 0, res->type,
IN_DEV_ORCONF(out_dev, NOXFRM));
if (!rth) {
- err = -ENOBUFS;
+ reason = SKB_DROP_REASON_NOMEM;
goto cleanup;
}
@@ -1857,9 +1859,9 @@ static int __mkroute_input(struct sk_buff *skb, const struct fib_result *res,
lwtunnel_set_redirect(&rth->dst);
skb_dst_set(skb, &rth->dst);
out:
- err = 0;
- cleanup:
- return err;
+ reason = SKB_NOT_DROPPED_YET;
+cleanup:
+ return reason;
}
#ifdef CONFIG_IP_ROUTE_MULTIPATH
@@ -2117,9 +2119,10 @@ int fib_multipath_hash(const struct net *net, const struct flowi4 *fl4,
}
#endif /* CONFIG_IP_ROUTE_MULTIPATH */
-static int ip_mkroute_input(struct sk_buff *skb, struct fib_result *res,
- struct in_device *in_dev, __be32 daddr,
- __be32 saddr, dscp_t dscp, struct flow_keys *hkeys)
+static enum skb_drop_reason
+ip_mkroute_input(struct sk_buff *skb, struct fib_result *res,
+ struct in_device *in_dev, __be32 daddr,
+ __be32 saddr, dscp_t dscp, struct flow_keys *hkeys)
{
#ifdef CONFIG_IP_ROUTE_MULTIPATH
if (res->fi && fib_info_num_path(res->fi) > 1) {
@@ -2333,9 +2336,8 @@ ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
}
make_route:
- err = ip_mkroute_input(skb, res, in_dev, daddr, saddr, dscp, flkeys);
- if (!err)
- reason = SKB_NOT_DROPPED_YET;
+ reason = ip_mkroute_input(skb, res, in_dev, daddr, saddr, dscp,
+ flkeys);
out:
return reason;
--
2.39.5
