From 58e35d1471287c59b9749fb82f04c628c36b9994 Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Fri, 5 Apr 2013 06:41:11 +0000 Subject: [PATCH] netfilter: ipv6: propagate routing errors from ip6_route_me_harder() Propagate routing errors from ip_route_me_harder() when dropping a packet using NF_DROP_ERR(). This makes userspace get the proper error instead of EPERM for everything. # ip -6 r a unreachable default table 100 # ip -6 ru add fwmark 0x1 lookup 100 # ip6tables -t mangle -A OUTPUT -d 2001:4860:4860::8888 -j MARK --set-mark 0x1 Old behaviour: PING 2001:4860:4860::8888(2001:4860:4860::8888) 56 data bytes ping: sendmsg: Operation not permitted ping: sendmsg: Operation not permitted ping: sendmsg: Operation not permitted New behaviour: PING 2001:4860:4860::8888(2001:4860:4860::8888) 56 data bytes ping: sendmsg: Network is unreachable ping: sendmsg: Network is unreachable ping: sendmsg: Network is unreachable Signed-off-by: Patrick McHardy Signed-off-by: Pablo Neira Ayuso --- net/ipv6/netfilter.c | 6 +++--- net/ipv6/netfilter/ip6table_mangle.c | 9 ++++++--- net/ipv6/netfilter/ip6table_nat.c | 6 ++++-- 3 files changed, 13 insertions(+), 8 deletions(-) diff --git a/net/ipv6/netfilter.c b/net/ipv6/netfilter.c index 429089cb073d..fc5fbd7f67af 100644 --- a/net/ipv6/netfilter.c +++ b/net/ipv6/netfilter.c @@ -29,7 +29,7 @@ int ip6_route_me_harder(struct sk_buff *skb) IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_OUTNOROUTES); LIMIT_NETDEBUG(KERN_DEBUG "ip6_route_me_harder: No more route.\n"); dst_release(dst); - return -EINVAL; + return dst->error; } /* Drop old route. */ @@ -43,7 +43,7 @@ int ip6_route_me_harder(struct sk_buff *skb) skb_dst_set(skb, NULL); dst = xfrm_lookup(net, dst, flowi6_to_flowi(&fl6), skb->sk, 0); if (IS_ERR(dst)) - return -1; + return PTR_ERR(dst); skb_dst_set(skb, dst); } #endif @@ -53,7 +53,7 @@ int ip6_route_me_harder(struct sk_buff *skb) if (skb_headroom(skb) < hh_len && pskb_expand_head(skb, HH_DATA_ALIGN(hh_len - skb_headroom(skb)), 0, GFP_ATOMIC)) - return -1; + return -ENOMEM; return 0; } diff --git a/net/ipv6/netfilter/ip6table_mangle.c b/net/ipv6/netfilter/ip6table_mangle.c index 6134a1ebfb1b..e075399d8b72 100644 --- a/net/ipv6/netfilter/ip6table_mangle.c +++ b/net/ipv6/netfilter/ip6table_mangle.c @@ -38,7 +38,7 @@ ip6t_mangle_out(struct sk_buff *skb, const struct net_device *out) struct in6_addr saddr, daddr; u_int8_t hop_limit; u_int32_t flowlabel, mark; - + int err; #if 0 /* root is playing with raw sockets. */ if (skb->len < sizeof(struct iphdr) || @@ -65,8 +65,11 @@ ip6t_mangle_out(struct sk_buff *skb, const struct net_device *out) !ipv6_addr_equal(&ipv6_hdr(skb)->daddr, &daddr) || skb->mark != mark || ipv6_hdr(skb)->hop_limit != hop_limit || - flowlabel != *((u_int32_t *)ipv6_hdr(skb)))) - return ip6_route_me_harder(skb) == 0 ? ret : NF_DROP; + flowlabel != *((u_int32_t *)ipv6_hdr(skb)))) { + err = ip6_route_me_harder(skb); + if (err < 0) + ret = NF_DROP_ERR(err); + } return ret; } diff --git a/net/ipv6/netfilter/ip6table_nat.c b/net/ipv6/netfilter/ip6table_nat.c index e0e788d25b14..97e2edd8c209 100644 --- a/net/ipv6/netfilter/ip6table_nat.c +++ b/net/ipv6/netfilter/ip6table_nat.c @@ -215,6 +215,7 @@ nf_nat_ipv6_local_fn(unsigned int hooknum, const struct nf_conn *ct; enum ip_conntrack_info ctinfo; unsigned int ret; + int err; /* root is playing with raw sockets. */ if (skb->len < sizeof(struct ipv6hdr)) @@ -227,8 +228,9 @@ nf_nat_ipv6_local_fn(unsigned int hooknum, if (!nf_inet_addr_cmp(&ct->tuplehash[dir].tuple.dst.u3, &ct->tuplehash[!dir].tuple.src.u3)) { - if (ip6_route_me_harder(skb)) - ret = NF_DROP; + err = ip6_route_me_harder(skb); + if (err < 0) + ret = NF_DROP_ERR(err); } #ifdef CONFIG_XFRM else if (!(IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED) && -- 2.20.1