user/sven/linux.git/include/net/ip6_route.h, branch v4.4.294

net: ipv6: fix return value of ip6_skb_dst_mtu

2021-07-28T07:12:34Z

commit 40fc3054b45820c28ea3c65e2c86d041dc244a8a upstream. Commit 628a5c561890 ("[INET]: Add IP(V6)_PMTUDISC_RPOBE") introduced ip6_skb_dst_mtu with return value of signed int which is inconsistent with actually returned values. Also 2 users of this function actually assign its value to unsigned int variable and only __xfrm6_output assigns result of this function to signed variable but actually uses as unsigned in further comparisons and calls. Change this function to return unsigned int value. Fixes: 628a5c561890 ("[INET]: Add IP(V6)_PMTUDISC_RPOBE") Reviewed-by: David Ahern Signed-off-by: Vadim Fedorenko Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: vrf: Fix dst reference counting

2020-05-10T08:26:22Z

commit 9ab179d83b4e31ea277a123492e419067c2f129a upstream. Vivek reported a kernel exception deleting a VRF with an active connection through it. The root cause is that the socket has a cached reference to a dst that is destroyed. Converting the dst_destroy to dst_release and letting proper reference counting kick in does not work as the dst has a reference to the device which needs to be released as well. I talked to Hannes about this at netdev and he pointed out the ipv4 and ipv6 dst handling has dst_ifdown for just this scenario. Rather than continuing with the reinvented dst wheel in VRF just remove it and leverage the ipv4 and ipv6 versions. Fixes: 193125dbd8eb2 ("net: Introduce VRF device driver") Fixes: 35402e3136634 ("net: Add IPv6 support to VRF device") Signed-off-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: ipv6: do not consider routes via gateways for anycast address check

2020-04-24T05:57:18Z

[ Upstream commit 03e2a984b6165621f287fadf5f4b5cd8b58dcaba ] The behaviour for what is considered an anycast address changed in commit 45e4fd26683c ("ipv6: Only create RTF_CACHE routes after encountering pmtu exception"). This now considers the first address in a subnet where there is a route via a gateway to be an anycast address. This breaks path MTU discovery and traceroutes when a host in a remote network uses the address at the start of a prefix (eg 2600:: advertised as 2600::/48 in the DFZ) as ICMP errors will not be sent to anycast addresses. This patch excludes any routes with a gateway, or via point to point links, like the behaviour previously from rt6_is_gw_or_nonexthop in net/ipv6/route.c. This can be tested with: ip link add v1 type veth peer name v2 ip netns add test ip netns exec test ip link set lo up ip link set v2 netns test ip link set v1 up ip netns exec test ip link set v2 up ip addr add 2001:db8::1/64 dev v1 nodad ip addr add 2001:db8:100:: dev lo nodad ip netns exec test ip addr add 2001:db8::2/64 dev v2 nodad ip netns exec test ip route add unreachable 2001:db8:1::1 ip netns exec test ip route add 2001:db8:100::/64 via 2001:db8::1 ip netns exec test sysctl net.ipv6.conf.all.forwarding=1 ip route add 2001:db8:1::1 via 2001:db8::2 ping -I 2001:db8::1 2001:db8:1::1 -c1 ping -I 2001:db8:100:: 2001:db8:1::1 -c1 ip addr delete 2001:db8:100:: dev lo ip netns delete test Currently the first ping will get back a destination unreachable ICMP error, but the second will never get a response, with "icmp6_send: acast source" logged. After this patch, both get destination unreachable ICMP replies. Fixes: 45e4fd26683c ("ipv6: Only create RTF_CACHE routes after encountering pmtu exception") Signed-off-by: Tim Stallard Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: ipv6: Compare lwstate in detecting duplicate nexthops

2017-07-21T05:44:55Z

commit f06b7549b79e29a672336d4e134524373fb7a232 upstream. Lennert reported a failure to add different mpls encaps in a multipath route: $ ip -6 route add 1234::/16 \ nexthop encap mpls 10 via fe80::1 dev ens3 \ nexthop encap mpls 20 via fe80::1 dev ens3 RTNETLINK answers: File exists The problem is that the duplicate nexthop detection does not compare lwtunnel configuration. Add it. Fixes: 19e42e451506 ("ipv6: support for fib route lwtunnel encap attributes") Signed-off-by: David Ahern Reported-by: João Taveira Araújo Reported-by: Lennert Buytenhek Acked-by: Roopa Prabhu Tested-by: Lennert Buytenhek Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

ipv6: initialize route null entry in addrconf_init()

2017-05-14T11:32:58Z

[ Upstream commit 2f460933f58eee3393aba64f0f6d14acb08d1724 ] Andrey reported a crash on init_net.ipv6.ip6_null_entry->rt6i_idev since it is always NULL. This is clearly wrong, we have code to initialize it to loopback_dev, unfortunately the order is still not correct. loopback_dev is registered very early during boot, we lose a chance to re-initialize it in notifier. addrconf_init() is called after ip6_route_init(), which means we have no chance to correct it. Fix it by moving this initialization explicitly after ipv6_add_dev(init_net.loopback_dev) in addrconf_init(). Reported-by: Andrey Konovalov Signed-off-by: Cong Wang Tested-by: Andrey Konovalov Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

ipv6: enforce flowi6_oif usage in ip6_dst_lookup_tail()

2016-03-03T23:07:05Z

[ Upstream commit 6f21c96a78b835259546d8f3fb4edff0f651d478 ] The current implementation of ip6_dst_lookup_tail basically ignore the egress ifindex match: if the saddr is set, ip6_route_output() purposefully ignores flowi6_oif, due to the commit d46a9d678e4c ("net: ipv6: Dont add RT6_LOOKUP_F_IFACE flag if saddr set"), if the saddr is 'any' the first route lookup in ip6_dst_lookup_tail fails, but upon failure a second lookup will be performed with saddr set, thus ignoring the ifindex constraint. This commit adds an output route lookup function variant, which allows the caller to specify lookup flags, and modify ip6_dst_lookup_tail() to enforce the ifindex match on the second lookup via said helper. ip6_route_output() becames now a static inline function build on top of ip6_route_output_flags(); as a side effect, out-of-tree modules need now a GPL license to access the output route lookup functionality. Signed-off-by: Paolo Abeni Acked-by: Hannes Frederic Sowa Acked-by: David Ahern Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

ipv6: kill sk_dst_lock

2015-12-03T16:32:06Z

While testing the np->opt RCU conversion, I found that UDP/IPv6 was using a mixture of xchg() and sk_dst_lock to protect concurrent changes to sk->sk_dst_cache, leading to possible corruptions and crashes. ip6_sk_dst_lookup_flow() uses sk_dst_check() anyway, so the simplest way to fix the mess is to remove sk_dst_lock completely, as we did for IPv4. __ip6_dst_store() and ip6_dst_store() share same implementation. sk_setup_caps() being called with socket lock being held or not, we have to use sk_dst_set() instead of __sk_dst_set() Note that I had to move the "np->dst_cookie = rt6_get_cookie(rt);" in ip6_dst_store() before the sk_setup_caps(sk, dst) call. This is because ip6_dst_store() can be called from process context, without any lock held. As soon as the dst is installed in sk->sk_dst_cache, dst can be freed from another cpu doing a concurrent ip6_dst_store() Doing the dst dereference before doing the install is needed to make sure no use after free would trigger. Signed-off-by: Eric Dumazet Reported-by: Dmitry Vyukov Signed-off-by: David S. Miller

ipv6: Pass struct net through ip6_fragment

2015-09-30T06:45:03Z

Signed-off-by: Eric W. Biederman

ipv6: Add rt6_get_cookie() function

2015-05-25T17:25:34Z

Instead of doing the rt6->rt6i_node check whenever we need to get the route's cookie. Refactor it into rt6_get_cookie(). It is a prep work to handle FLOWI_FLAG_KNOWN_NH and also percpu rt6_info later. Signed-off-by: Martin KaFai Lau Cc: Hannes Frederic Sowa Cc: Steffen Klassert Cc: Julian Anastasov Signed-off-by: David S. Miller

ipv6: Only create RTF_CACHE routes after encountering pmtu exception

2015-05-25T17:25:33Z

This patch creates a RTF_CACHE routes only after encountering a pmtu exception. After ip6_rt_update_pmtu() has inserted the RTF_CACHE route to the fib6 tree, the rt->rt6i_node->fn_sernum is bumped which will fail the ip6_dst_check() and trigger a relookup. Signed-off-by: Martin KaFai Lau Cc: Hannes Frederic Sowa Cc: Steffen Klassert Cc: Julian Anastasov Signed-off-by: David S. Miller