In this commit, we make ip_route_use_hint() return drop reasons. The
drop reasons that we return are similar to what we do in
ip_route_input_slow(), and no drop reasons are added in this commit.
Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn>
---
include/net/route.h | 7 ++++---
net/ipv4/ip_input.c | 9 ++++-----
net/ipv4/route.c | 26 ++++++++++++++++----------
3 files changed, 24 insertions(+), 18 deletions(-)
diff --git a/include/net/route.h b/include/net/route.h
index f4ab5412c9c9..4debc335d276 100644
--- a/include/net/route.h
+++ b/include/net/route.h
@@ -206,9 +206,10 @@ ip_mc_validate_source(struct sk_buff *skb, __be32 daddr, __be32 saddr,
enum skb_drop_reason
ip_route_input_noref(struct sk_buff *skb, __be32 daddr, __be32 saddr,
dscp_t dscp, struct net_device *dev);
-int ip_route_use_hint(struct sk_buff *skb, __be32 daddr, __be32 saddr,
- dscp_t dscp, struct net_device *dev,
- const struct sk_buff *hint);
+enum skb_drop_reason
+ip_route_use_hint(struct sk_buff *skb, __be32 daddr, __be32 saddr,
+ dscp_t dscp, struct net_device *dev,
+ const struct sk_buff *hint);
static inline enum skb_drop_reason
ip_route_input(struct sk_buff *skb, __be32 dst, __be32 src, dscp_t dscp,
diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c
index 513eb0c6435a..f0a4dda246ab 100644
--- a/net/ipv4/ip_input.c
+++ b/net/ipv4/ip_input.c
@@ -322,15 +322,14 @@ static int ip_rcv_finish_core(struct net *net, struct sock *sk,
int err, drop_reason;
struct rtable *rt;
- drop_reason = SKB_DROP_REASON_NOT_SPECIFIED;
-
if (ip_can_use_hint(skb, iph, hint)) {
- err = ip_route_use_hint(skb, iph->daddr, iph->saddr,
- ip4h_dscp(iph), dev, hint);
- if (unlikely(err))
+ drop_reason = ip_route_use_hint(skb, iph->daddr, iph->saddr,
+ ip4h_dscp(iph), dev, hint);
+ if (unlikely(drop_reason))
goto drop_error;
}
+ drop_reason = SKB_DROP_REASON_NOT_SPECIFIED;
if (READ_ONCE(net->ipv4.sysctl_ip_early_demux) &&
!skb_dst(skb) &&
!skb->sk &&
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index e248e5577d0e..7f969c865c81 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -2142,28 +2142,34 @@ ip_mkroute_input(struct sk_buff *skb, struct fib_result *res,
* assuming daddr is valid and the destination is not a local broadcast one.
* Uses the provided hint instead of performing a route lookup.
*/
-int ip_route_use_hint(struct sk_buff *skb, __be32 daddr, __be32 saddr,
- dscp_t dscp, struct net_device *dev,
- const struct sk_buff *hint)
+enum skb_drop_reason
+ip_route_use_hint(struct sk_buff *skb, __be32 daddr, __be32 saddr,
+ dscp_t dscp, struct net_device *dev,
+ const struct sk_buff *hint)
{
+ enum skb_drop_reason reason = SKB_DROP_REASON_NOT_SPECIFIED;
struct in_device *in_dev = __in_dev_get_rcu(dev);
struct rtable *rt = skb_rtable(hint);
struct net *net = dev_net(dev);
- enum skb_drop_reason reason;
- int err = -EINVAL;
u32 tag = 0;
if (!in_dev)
- return -EINVAL;
+ return reason;
- if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr))
+ if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr)) {
+ reason = SKB_DROP_REASON_IP_INVALID_SOURCE;
goto martian_source;
+ }
- if (ipv4_is_zeronet(saddr))
+ if (ipv4_is_zeronet(saddr)) {
+ reason = SKB_DROP_REASON_IP_INVALID_SOURCE;
goto martian_source;
+ }
- if (ipv4_is_loopback(saddr) && !IN_DEV_NET_ROUTE_LOCALNET(in_dev, net))
+ if (ipv4_is_loopback(saddr) && !IN_DEV_NET_ROUTE_LOCALNET(in_dev, net)) {
+ reason = SKB_DROP_REASON_IP_LOCALNET;
goto martian_source;
+ }
if (rt->rt_type != RTN_LOCAL)
goto skip_validate_source;
@@ -2179,7 +2185,7 @@ int ip_route_use_hint(struct sk_buff *skb, __be32 daddr, __be32 saddr,
martian_source:
ip_handle_martian_source(dev, in_dev, skb, daddr, saddr);
- return err;
+ return reason;
}
/* get device for dst_alloc with local routes */
--
2.39.5On 10/30/24 02:41, Menglong Dong wrote:
> diff --git a/net/ipv4/route.c b/net/ipv4/route.c
> index e248e5577d0e..7f969c865c81 100644
> --- a/net/ipv4/route.c
> +++ b/net/ipv4/route.c
> @@ -2142,28 +2142,34 @@ ip_mkroute_input(struct sk_buff *skb, struct fib_result *res,
> * assuming daddr is valid and the destination is not a local broadcast one.
> * Uses the provided hint instead of performing a route lookup.
> */
> -int ip_route_use_hint(struct sk_buff *skb, __be32 daddr, __be32 saddr,
> - dscp_t dscp, struct net_device *dev,
> - const struct sk_buff *hint)
> +enum skb_drop_reason
> +ip_route_use_hint(struct sk_buff *skb, __be32 daddr, __be32 saddr,
> + dscp_t dscp, struct net_device *dev,
> + const struct sk_buff *hint)
> {
> + enum skb_drop_reason reason = SKB_DROP_REASON_NOT_SPECIFIED;
> struct in_device *in_dev = __in_dev_get_rcu(dev);
> struct rtable *rt = skb_rtable(hint);
> struct net *net = dev_net(dev);
> - enum skb_drop_reason reason;
> - int err = -EINVAL;
> u32 tag = 0;
>
> if (!in_dev)
> - return -EINVAL;
> + return reason;
>
> - if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr))
> + if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr)) {
> + reason = SKB_DROP_REASON_IP_INVALID_SOURCE;
> goto martian_source;
> + }
>
> - if (ipv4_is_zeronet(saddr))
> + if (ipv4_is_zeronet(saddr)) {
> + reason = SKB_DROP_REASON_IP_INVALID_SOURCE;
> goto martian_source;
> + }
>
> - if (ipv4_is_loopback(saddr) && !IN_DEV_NET_ROUTE_LOCALNET(in_dev, net))
> + if (ipv4_is_loopback(saddr) && !IN_DEV_NET_ROUTE_LOCALNET(in_dev, net)) {
> + reason = IP_LOCALNET;
> goto martian_source;
> + }
>
> if (rt->rt_type != RTN_LOCAL)
> goto skip_validate_source;
Please explicitly replace also the
return 0;
with
return SKB_NOT_DROPPED_YET;
So that is clear the drop reason is always specified.
Thanks,
Paolo
On Tue, Nov 5, 2024 at 7:28 PM Paolo Abeni <pabeni@redhat.com> wrote:
>
> On 10/30/24 02:41, Menglong Dong wrote:
> > diff --git a/net/ipv4/route.c b/net/ipv4/route.c
> > index e248e5577d0e..7f969c865c81 100644
> > --- a/net/ipv4/route.c
> > +++ b/net/ipv4/route.c
> > @@ -2142,28 +2142,34 @@ ip_mkroute_input(struct sk_buff *skb, struct fib_result *res,
> > * assuming daddr is valid and the destination is not a local broadcast one.
> > * Uses the provided hint instead of performing a route lookup.
> > */
> > -int ip_route_use_hint(struct sk_buff *skb, __be32 daddr, __be32 saddr,
> > - dscp_t dscp, struct net_device *dev,
> > - const struct sk_buff *hint)
> > +enum skb_drop_reason
> > +ip_route_use_hint(struct sk_buff *skb, __be32 daddr, __be32 saddr,
> > + dscp_t dscp, struct net_device *dev,
> > + const struct sk_buff *hint)
> > {
> > + enum skb_drop_reason reason = SKB_DROP_REASON_NOT_SPECIFIED;
> > struct in_device *in_dev = __in_dev_get_rcu(dev);
> > struct rtable *rt = skb_rtable(hint);
> > struct net *net = dev_net(dev);
> > - enum skb_drop_reason reason;
> > - int err = -EINVAL;
> > u32 tag = 0;
> >
> > if (!in_dev)
> > - return -EINVAL;
> > + return reason;
> >
> > - if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr))
> > + if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr)) {
> > + reason = SKB_DROP_REASON_IP_INVALID_SOURCE;
> > goto martian_source;
> > + }
> >
> > - if (ipv4_is_zeronet(saddr))
> > + if (ipv4_is_zeronet(saddr)) {
> > + reason = SKB_DROP_REASON_IP_INVALID_SOURCE;
> > goto martian_source;
> > + }
> >
> > - if (ipv4_is_loopback(saddr) && !IN_DEV_NET_ROUTE_LOCALNET(in_dev, net))
> > + if (ipv4_is_loopback(saddr) && !IN_DEV_NET_ROUTE_LOCALNET(in_dev, net)) {
> > + reason = IP_LOCALNET;
> > goto martian_source;
> > + }
> >
> > if (rt->rt_type != RTN_LOCAL)
> > goto skip_validate_source;
>
> Please explicitly replace also the
>
> return 0;
>
> with
>
> return SKB_NOT_DROPPED_YET;
>
> So that is clear the drop reason is always specified.
Okay!
Thanks!
Menglong Dong
> Thanks,
>
> Paolo
>
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