From 2f326d9d9ff46fb2e45fb3b6ae77eff04332dde6 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Thu, 16 Feb 2023 16:28:38 +0000 Subject: ipv6: icmp6: add drop reason support to ndisc_router_discovery() Change ndisc_router_discovery() to return a drop reason. For the moment, return PKT_TOO_SMALL, NOT_SPECIFIED and SKB_CONSUMED. More reasons are added later. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/ipv6/ndisc.c | 37 +++++++++++++++++++------------------ 1 file changed, 19 insertions(+), 18 deletions(-) (limited to 'net/ipv6/ndisc.c') diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c index 514eb8cc7879..7c8ba308ea49 100644 --- a/net/ipv6/ndisc.c +++ b/net/ipv6/ndisc.c @@ -1231,20 +1231,21 @@ errout: rtnl_set_sk_err(net, RTNLGRP_ND_USEROPT, err); } -static void ndisc_router_discovery(struct sk_buff *skb) +static enum skb_drop_reason ndisc_router_discovery(struct sk_buff *skb) { struct ra_msg *ra_msg = (struct ra_msg *)skb_transport_header(skb); + bool send_ifinfo_notify = false; struct neighbour *neigh = NULL; - struct inet6_dev *in6_dev; + struct ndisc_options ndopts; struct fib6_info *rt = NULL; + struct inet6_dev *in6_dev; u32 defrtr_usr_metric; + unsigned int pref = 0; + __u32 old_if_flags; struct net *net; + SKB_DR(reason); int lifetime; - struct ndisc_options ndopts; int optlen; - unsigned int pref = 0; - __u32 old_if_flags; - bool send_ifinfo_notify = false; __u8 *opt = (__u8 *)(ra_msg + 1); @@ -1256,17 +1257,15 @@ static void ndisc_router_discovery(struct sk_buff *skb) __func__, skb->dev->name); if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) { ND_PRINTK(2, warn, "RA: source address is not link-local\n"); - return; - } - if (optlen < 0) { - ND_PRINTK(2, warn, "RA: packet too short\n"); - return; + return reason; } + if (optlen < 0) + return SKB_DROP_REASON_PKT_TOO_SMALL; #ifdef CONFIG_IPV6_NDISC_NODETYPE if (skb->ndisc_nodetype == NDISC_NODETYPE_HOST) { ND_PRINTK(2, warn, "RA: from host or unauthorized router\n"); - return; + return reason; } #endif @@ -1278,12 +1277,12 @@ static void ndisc_router_discovery(struct sk_buff *skb) if (!in6_dev) { ND_PRINTK(0, err, "RA: can't find inet6 device for %s\n", skb->dev->name); - return; + return reason; } if (!ndisc_parse_options(skb->dev, opt, optlen, &ndopts)) { ND_PRINTK(2, warn, "RA: invalid ND options\n"); - return; + return reason; } if (!ipv6_accept_ra(in6_dev)) { @@ -1365,7 +1364,7 @@ static void ndisc_router_discovery(struct sk_buff *skb) "RA: %s got default router without neighbour\n", __func__); fib6_info_release(rt); - return; + return reason; } } /* Set default route metric as specified by user */ @@ -1390,7 +1389,7 @@ static void ndisc_router_discovery(struct sk_buff *skb) ND_PRINTK(0, err, "RA: %s failed to add default route\n", __func__); - return; + return reason; } neigh = ip6_neigh_lookup(&rt->fib6_nh->fib_nh_gw6, @@ -1401,7 +1400,7 @@ static void ndisc_router_discovery(struct sk_buff *skb) "RA: %s got default router without neighbour\n", __func__); fib6_info_release(rt); - return; + return reason; } neigh->flags |= NTF_ROUTER; } else if (rt && IPV6_EXTRACT_PREF(rt->fib6_flags) != pref) { @@ -1488,6 +1487,7 @@ skip_linkparms: NEIGH_UPDATE_F_OVERRIDE_ISROUTER| NEIGH_UPDATE_F_ISROUTER, NDISC_ROUTER_ADVERTISEMENT, &ndopts); + reason = SKB_CONSUMED; } if (!ipv6_accept_ra(in6_dev)) { @@ -1598,6 +1598,7 @@ out: fib6_info_release(rt); if (neigh) neigh_release(neigh); + return reason; } static void ndisc_redirect_rcv(struct sk_buff *skb) @@ -1850,7 +1851,7 @@ enum skb_drop_reason ndisc_rcv(struct sk_buff *skb) break; case NDISC_ROUTER_ADVERTISEMENT: - ndisc_router_discovery(skb); + reason = ndisc_router_discovery(skb); break; case NDISC_REDIRECT: -- cgit v1.2.3