kernel/linux.git/include/net/ip_fib.h, branch v4.4.142

ipv4: lock mtu in fnhe when received PMTU < net.ipv4.route.min_pmtu

2018-05-30T05:49:04+00:00

[ Upstream commit d52e5a7e7ca49457dd31fc8b42fb7c0d58a31221 ] Prior to the rework of PMTU information storage in commit 2c8cec5c10bc ("ipv4: Cache learned PMTU information in inetpeer."), when a PMTU event advertising a PMTU smaller than net.ipv4.route.min_pmtu was received, we would disable setting the DF flag on packets by locking the MTU metric, and set the PMTU to net.ipv4.route.min_pmtu. Since then, we don't disable DF, and set PMTU to net.ipv4.route.min_pmtu, so the intermediate router that has this link with a small MTU will have to drop the packets. This patch reestablishes pre-2.6.39 behavior by splitting rtable->rt_pmtu into a bitfield with rt_mtu_locked and rt_pmtu. rt_mtu_locked indicates that we shouldn't set the DF bit on that path, and is checked in ip_dont_fragment(). One possible workaround is to set net.ipv4.route.min_pmtu to a value low enough to accommodate the lowest MTU encountered. Fixes: 2c8cec5c10bc ("ipv4: Cache learned PMTU information in inetpeer.") Signed-off-by: Sabrina Dubroca Reviewed-by: Stefano Brivio Signed-off-by: David S. Miller Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

ipv4: add reference counting to metrics

2017-06-07T10:05:59+00:00

[ Upstream commit 3fb07daff8e99243366a081e5129560734de4ada ] Andrey Konovalov reported crashes in ipv4_mtu() I could reproduce the issue with KASAN kernels, between 10.246.7.151 and 10.246.7.152 : 1) 20 concurrent netperf -t TCP_RR -H 10.246.7.152 -l 1000 & 2) At the same time run following loop : while : do ip ro add 10.246.7.152 dev eth0 src 10.246.7.151 mtu 1500 ip ro del 10.246.7.152 dev eth0 src 10.246.7.151 mtu 1500 done Cong Wang attempted to add back rt->fi in commit 82486aa6f1b9 ("ipv4: restore rt->fi for reference counting") but this proved to add some issues that were complex to solve. Instead, I suggested to add a refcount to the metrics themselves, being a standalone object (in particular, no reference to other objects) I tried to make this patch as small as possible to ease its backport, instead of being super clean. Note that we believe that only ipv4 dst need to take care of the metric refcount. But if this is wrong, this patch adds the basic infrastructure to extend this to other families. Many thanks to Julian Anastasov for reviewing this patch, and Cong Wang for his efforts on this problem. Fixes: 2860583fe840 ("ipv4: Kill rt->fi") Signed-off-by: Eric Dumazet Reported-by: Andrey Konovalov Reviewed-by: Julian Anastasov Acked-by: Cong Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

route: check and remove route cache when we get route

2016-03-03T23:07:07+00:00

[ Upstream commit deed49df7390d5239024199e249190328f1651e7 ] Since the gc of ipv4 route was removed, the route cached would has no chance to be removed, and even it has been timeout, it still could be used, cause no code to check it's expires. Fix this issue by checking and removing route cache when we get route. Signed-off-by: Xin Long Acked-by: Hannes Frederic Sowa Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2015-11-03T18:41:45+00:00

Minor overlapping changes in net/ipv4/ipmr.c, in 'net' we were fixing the "BH-ness" of the counter bumps whilst in 'net-next' the functions were modified to take an explicit 'net' parameter. Signed-off-by: David S. Miller

ipv4: fix to not remove local route on link down

2015-11-01T21:57:39+00:00

When fib_netdev_event calls fib_disable_ip on NETDEV_DOWN event we should not delete the local routes if the local address is still present. The confusion comes from the fact that both fib_netdev_event and fib_inetaddr_event use the NETDEV_DOWN constant. Fix it by returning back the variable 'force'. Steps to reproduce: modprobe dummy ifconfig dummy0 192.168.168.1 up ifconfig dummy0 down ip route list table local | grep dummy | grep host local 192.168.168.1 dev dummy0 proto kernel scope host src 192.168.168.1 Fixes: 8a3d03166f19 ("net: track link-status of ipv4 nexthops") Signed-off-by: Julian Anastasov Signed-off-by: David S. Miller

net: Refactor path selection in __ip_route_output_key_hash

2015-10-07T11:27:44+00:00

VRF device needs the same path selection following lookup to set source address. Rather than duplicating code, move existing code into a function that is exported to modules. Code move only; no functional change. Signed-off-by: David Ahern Signed-off-by: David S. Miller

ipv4: L3 hash-based multipath

2015-10-05T09:59:21+00:00

Replaces the per-packet multipath with a hash-based multipath using source and destination address. Signed-off-by: Peter Nørlund Signed-off-by: David S. Miller

net: Fix behaviour of unreachable, blackhole and prohibit routes

2015-09-21T04:45:08+00:00

Man page of ip-route(8) says following about route types: unreachable - these destinations are unreachable. Packets are dis‐ carded and the ICMP message host unreachable is generated. The local senders get an EHOSTUNREACH error. blackhole - these destinations are unreachable. Packets are dis‐ carded silently. The local senders get an EINVAL error. prohibit - these destinations are unreachable. Packets are discarded and the ICMP message communication administratively prohibited is generated. The local senders get an EACCES error. In the inet6 address family, this was correct, except the local senders got ENETUNREACH error instead of EHOSTUNREACH in case of unreachable route. In the inet address family, all three route types generated ICMP message net unreachable, and the local senders got ENETUNREACH error. In both address families all three route types now behave consistently with documentation. Signed-off-by: Nikola Forró Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2015-08-01T06:52:20+00:00

Conflicts: arch/s390/net/bpf_jit_comp.c drivers/net/ethernet/ti/netcp_ethss.c net/bridge/br_multicast.c net/ipv4/ip_fragment.c All four conflicts were cases of simple overlapping changes. Signed-off-by: David S. Miller

ipv4: consider TOS in fib_select_default

2015-07-25T05:46:11+00:00

fib_select_default considers alternative routes only when res->fi is for the first alias in res->fa_head. In the common case this can happen only when the initial lookup matches the first alias with highest TOS value. This prevents the alternative routes to require specific TOS. This patch solves the problem as follows: - routes that require specific TOS should be returned by fib_select_default only when TOS matches, as already done in fib_table_lookup. This rule implies that depending on the TOS we can have many different lists of alternative gateways and we have to keep the last used gateway (fa_default) in first alias for the TOS instead of using single tb_default value. - as the aliases are ordered by many keys (TOS desc, fib_priority asc), we restrict the possible results to routes with matching TOS and lowest metric (fib_priority) and routes that match any TOS, again with lowest metric. For example, packet with TOS 8 can not use gw3 (not lowest metric), gw4 (different TOS) and gw6 (not lowest metric), all other gateways can be used: tos 8 via gw1 metric 2 <--- res->fa_head and res->fi tos 8 via gw2 metric 2 tos 8 via gw3 metric 3 tos 4 via gw4 tos 0 via gw5 tos 0 via gw6 metric 1 Reported-by: Hagen Paul Pfeifer Signed-off-by: Julian Anastasov Signed-off-by: David S. Miller