From b8e8a86337c25941cb06e9a1c8ee01ab9aab0cc2 Mon Sep 17 00:00:00 2001 From: Eiichi Tsukata Date: Tue, 25 Jun 2019 12:08:01 +0900 Subject: net/ipv6: Fix misuse of proc_dointvec "skip_notify_on_dev_down" /proc/sys/net/ipv6/route/skip_notify_on_dev_down assumes given value to be 0 or 1. Use proc_dointvec_minmax instead of proc_dointvec. Fixes: 7c6bb7d2faaf ("net/ipv6: Add knob to skip DELROUTE message ondevice down") Signed-off-by: Eiichi Tsukata Signed-off-by: David S. Miller --- net/ipv6/route.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/ipv6/route.c') diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 11ad62effd56..aade636c6be6 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -5281,7 +5281,7 @@ static struct ctl_table ipv6_route_table_template[] = { .data = &init_net.ipv6.sysctl.skip_notify_on_dev_down, .maxlen = sizeof(int), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_dointvec_minmax, .extra1 = &zero, .extra2 = &one, }, -- cgit v1.2.3 From 2c6b55f45d53420d8310d41310e0e2cd41fe073f Mon Sep 17 00:00:00 2001 From: Nicolas Dichtel Date: Mon, 24 Jun 2019 16:01:09 +0200 Subject: ipv6: fix neighbour resolution with raw socket The scenario is the following: the user uses a raw socket to send an ipv6 packet, destinated to a not-connected network, and specify a connected nh. Here is the corresponding python script to reproduce this scenario: import socket IPPROTO_RAW = 255 send_s = socket.socket(socket.AF_INET6, socket.SOCK_RAW, IPPROTO_RAW) # scapy # p = IPv6(src='fd00:100::1', dst='fd00:200::fa')/ICMPv6EchoRequest() # str(p) req = b'`\x00\x00\x00\x00\x08:@\xfd\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\xfd\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xfa\x80\x00\x81\xc0\x00\x00\x00\x00' send_s.sendto(req, ('fd00:175::2', 0, 0, 0)) fd00:175::/64 is a connected route and fd00:200::fa is not a connected host. With this scenario, the kernel starts by sending a NS to resolve fd00:175::2. When it receives the NA, it flushes its queue and try to send the initial packet. But instead of sending it, it sends another NS to resolve fd00:200::fa, which obvioulsy fails, thus the packet is dropped. If the user sends again the packet, it now uses the right nh (fd00:175::2). The problem is that ip6_dst_lookup_neigh() uses the rt6i_gateway, which is :: because the associated route is a connected route, thus it uses the dst addr of the packet. Let's use rt6_nexthop() to choose the right nh. Signed-off-by: Nicolas Dichtel Signed-off-by: David S. Miller --- net/ipv6/route.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'net/ipv6/route.c') diff --git a/net/ipv6/route.c b/net/ipv6/route.c index aade636c6be6..97a843cf164c 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -218,7 +218,8 @@ static struct neighbour *ip6_dst_neigh_lookup(const struct dst_entry *dst, { const struct rt6_info *rt = container_of(dst, struct rt6_info, dst); - return ip6_neigh_lookup(&rt->rt6i_gateway, dst->dev, skb, daddr); + return ip6_neigh_lookup(rt6_nexthop(rt, &in6addr_any), + dst->dev, skb, daddr); } static void ip6_confirm_neigh(const struct dst_entry *dst, const void *daddr) -- cgit v1.2.3