In this commit, we make ip_route_input_rcu() return drop reasons, which come from ip_route_input_mc() and ip_route_input_slow(). The only caller of ip_route_input_rcu() is ip_route_input_noref(). We adjust it by making it return -EINVAL on error and ignore the reasons that ip_route_input_rcu() returns. In the following patch, we will make ip_route_input_noref() returns the drop reasons. Signed-off-by: Menglong Dong <dongml2@xxxxxxxxxxxxxxx> --- v4: - collapse the 2 lines that we modify in inet_rtm_getroute() --- net/ipv4/route.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 1c4727504909..1926a8a1a83a 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -2435,9 +2435,10 @@ ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr, } /* called with rcu_read_lock held */ -static int ip_route_input_rcu(struct sk_buff *skb, __be32 daddr, __be32 saddr, - dscp_t dscp, struct net_device *dev, - struct fib_result *res) +static enum skb_drop_reason +ip_route_input_rcu(struct sk_buff *skb, __be32 daddr, __be32 saddr, + dscp_t dscp, struct net_device *dev, + struct fib_result *res) { /* Multicast recognition logic is moved from route cache to here. * The problem was that too many Ethernet cards have broken/missing @@ -2480,23 +2481,23 @@ static int ip_route_input_rcu(struct sk_buff *skb, __be32 daddr, __be32 saddr, reason = ip_route_input_mc(skb, daddr, saddr, dscp, dev, our); } - return reason ? -EINVAL : 0; + return reason; } - return ip_route_input_slow(skb, daddr, saddr, dscp, dev, res) ? -EINVAL : 0; + return ip_route_input_slow(skb, daddr, saddr, dscp, dev, res); } int ip_route_input_noref(struct sk_buff *skb, __be32 daddr, __be32 saddr, dscp_t dscp, struct net_device *dev) { + enum skb_drop_reason reason; struct fib_result res; - int err; rcu_read_lock(); - err = ip_route_input_rcu(skb, daddr, saddr, dscp, dev, &res); + reason = ip_route_input_rcu(skb, daddr, saddr, dscp, dev, &res); rcu_read_unlock(); - return err; + return reason ? -EINVAL : 0; } EXPORT_SYMBOL(ip_route_input_noref); @@ -3308,7 +3309,7 @@ static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh, skb->mark = mark; err = ip_route_input_rcu(skb, dst, src, inet_dsfield_to_dscp(rtm->rtm_tos), - dev, &res); + dev, &res) ? -EINVAL : 0; rt = skb_rtable(skb); if (err == 0 && rt->dst.error) -- 2.39.5