kernel/git/stable/linux.git/net/ipv6, branch linux-4.11.y

net: ipv6: Compare lwstate in detecting duplicate nexthops

2017-07-21T05:00:07+00:00

[ Upstream commit f06b7549b79e29a672336d4e134524373fb7a232 ] 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: dad: don't remove dynamic addresses if link is down

2017-07-21T05:00:07+00:00

[ Upstream commit ec8add2a4c9df723c94a863b8fcd6d93c472deed ] Currently, when the link for $DEV is down, this command succeeds but the address is removed immediately by DAD (1): ip addr add 1111::12/64 dev $DEV valid_lft 3600 preferred_lft 1800 In the same situation, this will succeed and not remove the address (2): ip addr add 1111::12/64 dev $DEV ip addr change 1111::12/64 dev $DEV valid_lft 3600 preferred_lft 1800 The comment in addrconf_dad_begin() when !IF_READY makes it look like this is the intended behavior, but doesn't explain why: * If the device is not ready: * - keep it tentative if it is a permanent address. * - otherwise, kill it. We clearly cannot prevent userspace from doing (2), but we can make (1) work consistently with (2). addrconf_dad_stop() is only called in two cases: if DAD failed, or to skip DAD when the link is down. In that second case, the fix is to avoid deleting the address, like we already do for permanent addresses. Fixes: 3c21edbd1137 ("[IPV6]: Defer IPv6 device initialization until the link becomes ready.") Signed-off-by: Sabrina Dubroca Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: account for current skb length when deciding about UFO

2017-07-21T05:00:05+00:00

[ Upstream commit a5cb659bbc1c8644efa0c3138a757a1e432a4880 ] Our customer encountered stuck NFS writes for blocks starting at specific offsets w.r.t. page boundary caused by networking stack sending packets via UFO enabled device with wrong checksum. The problem can be reproduced by composing a long UDP datagram from multiple parts using MSG_MORE flag: sendto(sd, buff, 1000, MSG_MORE, ...); sendto(sd, buff, 1000, MSG_MORE, ...); sendto(sd, buff, 3000, 0, ...); Assume this packet is to be routed via a device with MTU 1500 and NETIF_F_UFO enabled. When second sendto() gets into __ip_append_data(), this condition is tested (among others) to decide whether to call ip_ufo_append_data(): ((length + fragheaderlen) > mtu) || (skb && skb_is_gso(skb)) At the moment, we already have skb with 1028 bytes of data which is not marked for GSO so that the test is false (fragheaderlen is usually 20). Thus we append second 1000 bytes to this skb without invoking UFO. Third sendto(), however, has sufficient length to trigger the UFO path so that we end up with non-UFO skb followed by a UFO one. Later on, udp_send_skb() uses udp_csum() to calculate the checksum but that assumes all fragments have correct checksum in skb->csum which is not true for UFO fragments. When checking against MTU, we need to add skb->len to length of new segment if we already have a partially filled skb and fragheaderlen only if there isn't one. In the IPv6 case, skb can only be null if this is the first segment so that we have to use headersize (length of the first IPv6 header) rather than fragheaderlen (length of IPv6 header of further fragments) for skb == NULL. Fixes: e89e9cf539a2 ("[IPv4/IPv6]: UFO Scatter-gather approach") Fixes: e4c5e13aa45c ("ipv6: Should use consistent conditional judgement for ip6 fragment between __ip6_append_data and ip6_finish_output") Signed-off-by: Michal Kubecek Acked-by: Vlad Yasevich Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

ipv6: avoid unregistering inet6_dev for loopback

2017-07-21T05:00:05+00:00

[ Upstream commit 60abc0be96e00ca71bac083215ac91ad2e575096 ] The per netns loopback_dev->ip6_ptr is unregistered and set to NULL when its mtu is set to smaller than IPV6_MIN_MTU, this leads to that we could set rt->rt6i_idev NULL after a rt6_uncached_list_flush_dev() and then crash after another call. In this case we should just bring its inet6_dev down, rather than unregistering it, at least prior to commit 176c39af29bc ("netns: fix addrconf_ifdown kernel panic") we always override the case for loopback. Thanks a lot to Andrey for finding a reliable reproducer. Fixes: 176c39af29bc ("netns: fix addrconf_ifdown kernel panic") Reported-by: Andrey Konovalov Cc: Andrey Konovalov Cc: Daniel Lezcano Cc: David Ahern Signed-off-by: Cong Wang Acked-by: David Ahern Tested-by: Andrey Konovalov Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

xfrm6: Fix IPv6 payload_len in xfrm6_transport_finish

2017-07-05T12:41:40+00:00

commit 7c88e21aefcf86fb41b48b2e04528db5a30fbe18 upstream. IPv6 payload length indicates the size of the payload, including any extension headers. In xfrm6_transport_finish, ipv6_hdr(skb)->payload_len is set to the payload size only, regardless of the presence of any extension headers. After ESP GRO transport mode decapsulation, ipv6_rcv trims the packet according to the wrong payload_len, thus corrupting the packet. Set payload_len to account for extension headers as well. Fixes: 7785bba299a8 ("esp: Add a software GRO codepath") Signed-off-by: Yossi Kuperman Signed-off-by: Steffen Klassert Signed-off-by: Greg Kroah-Hartman

ipv6: Do not leak throw route references

2017-07-05T12:41:37+00:00

[ Upstream commit 07f615574f8ac499875b21c1142f26308234a92c ] While commit 73ba57bfae4a ("ipv6: fix backtracking for throw routes") does good job on error propagation to the fib_rules_lookup() in fib rules core framework that also corrects throw routes handling, it does not solve route reference leakage problem happened when we return -EAGAIN to the fib_rules_lookup() and leave routing table entry referenced in arg->result. If rule with matched throw route isn't last matched in the list we overwrite arg->result losing reference on throw route stored previously forever. We also partially revert commit ab997ad40839 ("ipv6: fix the incorrect return value of throw route") since we never return routing table entry with dst.error == -EAGAIN when CONFIG_IPV6_MULTIPLE_TABLES is on. Also there is no point to check for RTF_REJECT flag since it is always set throw route. Fixes: 73ba57bfae4a ("ipv6: fix backtracking for throw routes") Signed-off-by: Serhey Popovych Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

ipv6: fix calling in6_ifa_hold incorrectly for dad work

2017-07-05T12:41:36+00:00

[ Upstream commit f8a894b218138888542a5058d0e902378fd0d4ec ] Now when starting the dad work in addrconf_mod_dad_work, if the dad work is idle and queued, it needs to hold ifa. The problem is there's one gap in [1], during which if the pending dad work is removed elsewhere. It will miss to hold ifa, but the dad word is still idea and queue. if (!delayed_work_pending(&ifp->dad_work)) in6_ifa_hold(ifp); <--------------[1] mod_delayed_work(addrconf_wq, &ifp->dad_work, delay); An use-after-free issue can be caused by this. Chen Wei found this issue when WARN_ON(!hlist_unhashed(&ifp->addr_lst)) in net6_ifa_finish_destroy was hit because of it. As Hannes' suggestion, this patch is to fix it by holding ifa first in addrconf_mod_dad_work, then calling mod_delayed_work and putting ifa if the dad_work is already in queue. Note that this patch did not choose to fix it with: if (!mod_delayed_work(delay)) in6_ifa_hold(ifp); As with it, when delay == 0, dad_work would be scheduled immediately, all addrconf_mod_dad_work(0) callings had to be moved under ifp->lock. Reported-by: Wei Chen Suggested-by: Hannes Frederic Sowa Acked-by: Hannes Frederic Sowa Signed-off-by: Xin Long Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: don't global ICMP rate limit packets originating from loopback

2017-07-05T12:41:36+00:00

[ Upstream commit 849a44de91636c24cea799cb8ad8c36433feb913 ] Florian Weimer seems to have a glibc test-case which requires that loopback interfaces does not get ICMP ratelimited. This was broken by commit c0303efeab73 ("net: reduce cycles spend on ICMP replies that gets rate limited"). An ICMP response will usually be routed back-out the same incoming interface. Thus, take advantage of this and skip global ICMP ratelimit when the incoming device is loopback. In the unlikely event that the outgoing it not loopback, due to strange routing policy rules, ICMP rate limiting still works via peer ratelimiting via icmpv4_xrlim_allow(). Thus, we should still comply with RFC1812 (section 4.3.2.8 "Rate Limiting"). This seems to fix the reproducer given by Florian. While still avoiding to perform expensive and unneeded outgoing route lookup for rate limited packets (in the non-loopback case). Fixes: c0303efeab73 ("net: reduce cycles spend on ICMP replies that gets rate limited") Reported-by: Florian Weimer Reported-by: "H.J. Lu" Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

proc: snmp6: Use correct type in memset

2017-07-05T12:41:36+00:00

[ Upstream commit 3500cd73dff48f28f4ba80c171c4c80034d40f76 ] Reading /proc/net/snmp6 yields bogus values on 32 bit kernels. Use "u64" instead of "unsigned long" in sizeof(). Fixes: 4a4857b1c81e ("proc: Reduce cache miss in snmp6_seq_show") Signed-off-by: Christian Perle Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: ipv6: Release route when device is unregistering

2017-07-05T12:41:35+00:00

[ Upstream commit 8397ed36b7c585f8d3e06c431f4137309124f78f ] Roopa reported attempts to delete a bond device that is referenced in a multipath route is hanging: $ ifdown bond2 # ifupdown2 command that deletes virtual devices unregister_netdevice: waiting for bond2 to become free. Usage count = 2 Steps to reproduce: echo 1 > /proc/sys/net/ipv6/conf/all/ignore_routes_with_linkdown ip link add dev bond12 type bond ip link add dev bond13 type bond ip addr add 2001:db8:2::0/64 dev bond12 ip addr add 2001:db8:3::0/64 dev bond13 ip route add 2001:db8:33::0/64 nexthop via 2001:db8:2::2 nexthop via 2001:db8:3::2 ip link del dev bond12 ip link del dev bond13 The root cause is the recent change to keep routes on a linkdown. Update the check to detect when the device is unregistering and release the route for that case. Fixes: a1a22c12060e4 ("net: ipv6: Keep nexthop of multipath route on admin down") Reported-by: Roopa Prabhu Signed-off-by: David Ahern Acked-by: Roopa Prabhu Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman