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path: root/include/net/ip6_route.h
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2024-07-14ipv6: fix source address selection with route leakNicolas Dichtel
By default, an address assigned to the output interface is selected when the source address is not specified. This is problematic when a route, configured in a vrf, uses an interface from another vrf (aka route leak). The original vrf does not own the selected source address. Let's add a check against the output interface and call the appropriate function to select the source address. CC: stable@vger.kernel.org Fixes: 0d240e7811c4 ("net: vrf: Implement get_saddr for IPv6") Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Link: https://patch.msgid.link/20240710081521.3809742-3-nicolas.dichtel@6wind.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-29ipv6: introduce dst_rt6_info() helperEric Dumazet
Instead of (struct rt6_info *)dst casts, we can use : #define dst_rt6_info(_ptr) \ container_of_const(_ptr, struct rt6_info, dst) Some places needed missing const qualifiers : ip6_confirm_neigh(), ipv6_anycast_destination(), ipv6_unicast_destination(), has_gateway() v2: added missing parts (David Ahern) Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-03-01ipv6: annotate data-races around cnf.mtu6Eric Dumazet
idev->cnf.mtu6 might be read locklessly, add appropriate READ_ONCE() and WRITE_ONCE() annotations. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-02-12net/ipv6: set expires in rt6_add_dflt_router().Kui-Feng Lee
Pass the duration of a lifetime (in seconds) to the function rt6_add_dflt_router() so that it can properly set the expiration time. The function ndisc_router_discovery() is the only one that calls rt6_add_dflt_router(), and it will later set the expiration time for the route created by rt6_add_dflt_router(). However, there is a gap of time between calling rt6_add_dflt_router() and setting the expiration time in ndisc_router_discovery(). During this period, there is a possibility that a new route may be removed from the routing table. By setting the correct expiration time in rt6_add_dflt_router(), we can prevent this from happening. The reason for setting RTF_EXPIRES in rt6_add_dflt_router() is to start the Garbage Collection (GC) timer, as it only activates when a route with RTF_EXPIRES is added to a table. Suggested-by: David Ahern <dsahern@kernel.org> Reviewed-by: Hangbin Liu <liuhangbin@gmail.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-09-19ipv6: lockless IPV6_ADDR_PREFERENCES implementationEric Dumazet
We have data-races while reading np->srcprefs Switch the field to a plain byte, add READ_ONCE() and WRITE_ONCE() annotations where needed, and IPV6_ADDR_PREFERENCES setsockopt() can now be lockless. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20230918142321.1794107-1-edumazet@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-09-15ipv6: lockless IPV6_MTU_DISCOVER implementationEric Dumazet
Most np->pmtudisc reads are racy. Move this 3bit field on a full byte, add annotations and make IPV6_MTU_DISCOVER setsockopt() lockless. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-07-28IPv6: add extack info for IPv6 address add/deleteHangbin Liu
Add extack info for IPv6 address add/delete, which would be useful for users to understand the problem without having to read kernel code. Suggested-by: Beniamino Galvani <bgalvani@redhat.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-28net: dst: Prevent false sharing vs. dst_entry:: __refcntWangyang Guo
dst_entry::__refcnt is highly contended in scenarios where many connections happen from and to the same IP. The reference count is an atomic_t, so the reference count operations have to take the cache-line exclusive. Aside of the unavoidable reference count contention there is another significant problem which is caused by that: False sharing. perf top identified two affected read accesses. dst_entry::lwtstate and rtable::rt_genid. dst_entry:__refcnt is located at offset 64 of dst_entry, which puts it into a seperate cacheline vs. the read mostly members located at the beginning of the struct. That prevents false sharing vs. the struct members in the first 64 bytes of the structure, but there is also dst_entry::lwtstate which is located after the reference count and in the same cache line. This member is read after a reference count has been acquired. struct rtable embeds a struct dst_entry at offset 0. struct dst_entry has a size of 112 bytes, which means that the struct members of rtable which follow the dst member share the same cache line as dst_entry::__refcnt. Especially rtable::rt_genid is also read by the contexts which have a reference count acquired already. When dst_entry:__refcnt is incremented or decremented via an atomic operation these read accesses stall. This was found when analysing the memtier benchmark in 1:100 mode, which amplifies the problem extremly. Move the rt[6i]_uncached[_list] members out of struct rtable and struct rt6_info into struct dst_entry to provide padding and move the lwtstate member after that so it ends up in the same cache line. The resulting improvement depends on the micro-architecture and the number of CPUs. It ranges from +20% to +120% with a localhost memtier/memcached benchmark. [ tglx: Rearrange struct ] Signed-off-by: Wangyang Guo <wangyang.guo@intel.com> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20230323102800.042297517@linutronix.de Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-24ipv6: Make ip6_route_output_flags_noref() static.Guillaume Nault
This function is only used in net/ipv6/route.c and has no reason to be visible outside of it. Signed-off-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/50706db7f675e40b3594d62011d9363dce32b92e.1674495822.git.gnault@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-22net: add missing includes and forward declarations under net/Jakub Kicinski
This patch adds missing includes to headers under include/net. All these problems are currently masked by the existing users including the missing dependency before the broken header. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-19ipv6: ip6_skb_dst_mtu() cleanupsEric Dumazet
Use const attribute where we can, and cache skb_dst() Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20211119022355.2985984-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Build failure in drivers/net/wwan/mhi_wwan_mbim.c: add missing parameter (0, assuming we don't want buffer pre-alloc). Conflict in drivers/net/dsa/sja1105/sja1105_main.c between: 589918df9322 ("net: dsa: sja1105: be stateless with FDB entries on SJA1105P/Q/R/S/SJA1110 too") 0fac6aa098ed ("net: dsa: sja1105: delete the best_effort_vlan_filtering mode") Follow the instructions from the commit message of the former commit - removed the if conditions. When looking at commit 589918df9322 ("net: dsa: sja1105: be stateless with FDB entries on SJA1105P/Q/R/S/SJA1110 too") note that the mask_iotag fields get removed by the following patch. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-03net: ipv6: fix returned variable type in ip6_skb_dst_mtuAntoine Tenart
The patch fixing the returned value of ip6_skb_dst_mtu (int -> unsigned int) was rebased between its initial review and the version applied. In the meantime fade56410c22 was applied, which added a new variable (int) used as the returned value. This lead to a mismatch between the function prototype and the variable used as the return value. Fixes: 40fc3054b458 ("net: ipv6: fix return value of ip6_skb_dst_mtu") Cc: Vadim Fedorenko <vfedorenko@novek.ru> Signed-off-by: Antoine Tenart <atenart@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21net: ipv6: introduce ip6_dst_mtu_maybe_forwardVadim Fedorenko
Replace ip6_dst_mtu_forward with ip6_dst_mtu_maybe_forward and reuse this code in ip6_mtu. Actually these two functions were almost duplicates, this change will simplify the maintaince of mtu calculation code. Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-02net: ipv6: fix return value of ip6_skb_dst_mtuVadim Fedorenko
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 <dsahern@kernel.org> Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-28net: lwtunnel: handle MTU calculation in forwadingVadim Fedorenko
Commit 14972cbd34ff ("net: lwtunnel: Handle fragmentation") moved fragmentation logic away from lwtunnel by carry encap headroom and use it in output MTU calculation. But the forwarding part was not covered and created difference in MTU for output and forwarding and further to silent drops on ipv4 forwarding path. Fix it by taking into account lwtunnel encap headroom. The same commit also introduced difference in how to treat RTAX_MTU in IPv4 and IPv6 where latter explicitly removes lwtunnel encap headroom from route MTU. Make IPv4 version do the same. Fixes: 14972cbd34ff ("net: lwtunnel: Handle fragmentation") Suggested-by: David Ahern <dsahern@gmail.com> Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-01-26net: allow user to set metric on default route learned via Router AdvertisementPraveen Chaudhary
For IPv4, default route is learned via DHCPv4 and user is allowed to change metric using config etc/network/interfaces. But for IPv6, default route can be learned via RA, for which, currently a fixed metric value 1024 is used. Ideally, user should be able to configure metric on default route for IPv6 similar to IPv4. This patch adds sysctl for the same. Logs: For IPv4: Config in etc/network/interfaces: auto eth0 iface eth0 inet dhcp metric 4261413864 IPv4 Kernel Route Table: $ ip route list default via 172.21.47.1 dev eth0 metric 4261413864 FRR Table, if a static route is configured: [In real scenario, it is useful to prefer BGP learned default route over DHCPv4 default route.] Codes: K - kernel route, C - connected, S - static, R - RIP, O - OSPF, I - IS-IS, B - BGP, P - PIM, E - EIGRP, N - NHRP, T - Table, v - VNC, V - VNC-Direct, A - Babel, D - SHARP, > - selected route, * - FIB route S>* 0.0.0.0/0 [20/0] is directly connected, eth0, 00:00:03 K 0.0.0.0/0 [254/1000] via 172.21.47.1, eth0, 6d08h51m i.e. User can prefer Default Router learned via Routing Protocol in IPv4. Similar behavior is not possible for IPv6, without this fix. After fix [for IPv6]: sudo sysctl -w net.ipv6.conf.eth0.net.ipv6.conf.eth0.ra_defrtr_metric=1996489705 IP monitor: [When IPv6 RA is received] default via fe80::xx16:xxxx:feb3:ce8e dev eth0 proto ra metric 1996489705 pref high Kernel IPv6 routing table $ ip -6 route list default via fe80::be16:65ff:feb3:ce8e dev eth0 proto ra metric 1996489705 expires 21sec hoplimit 64 pref high FRR Table, if a static route is configured: [In real scenario, it is useful to prefer BGP learned default route over IPv6 RA default route.] Codes: K - kernel route, C - connected, S - static, R - RIPng, O - OSPFv3, I - IS-IS, B - BGP, N - NHRP, T - Table, v - VNC, V - VNC-Direct, A - Babel, D - SHARP, > - selected route, * - FIB route S>* ::/0 [20/0] is directly connected, eth0, 00:00:06 K ::/0 [119/1001] via fe80::xx16:xxxx:feb3:ce8e, eth0, 6d07h43m If the metric is changed later, the effect will be seen only when next IPv6 RA is received, because the default route must be fully controlled by RA msg. Below metric is changed from 1996489705 to 1996489704. $ sudo sysctl -w net.ipv6.conf.eth0.ra_defrtr_metric=1996489704 net.ipv6.conf.eth0.ra_defrtr_metric = 1996489704 IP monitor: [On next IPv6 RA msg, Kernel deletes prev route and installs new route with updated metric] Deleted default via fe80::xx16:xxxx:feb3:ce8e dev eth0 proto ra metric 1996489705 expires 3sec hoplimit 64 pref high default via fe80::xx16:xxxx:feb3:ce8e dev eth0 proto ra metric 1996489704 pref high Signed-off-by: Praveen Chaudhary <pchaudhary@linkedin.com> Signed-off-by: Zhenggen Xu <zxu@linkedin.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20210125214430.24079-1-pchaudhary@linkedin.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-05-18ipv6: lift copy_from_user out of ipv6_route_ioctlChristoph Hellwig
Prepare for better compat ioctl handling by moving the user copy out of ipv6_route_ioctl. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-28net: ipv6: new arg skip_notify to ip6_rt_delRoopa Prabhu
Used in subsequent work to skip route delete notifications on nexthop deletes. Suggested-by: David Ahern <dsahern@gmail.com> Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-07net: ipv6: do not consider routes via gateways for anycast address checkTim Stallard
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 <code@timstallard.me.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-29net: ip6_route: Replace zero-length array with flexible-array memberGustavo A. R. Silva
The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-27Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
The new route handling in ip_mc_finish_output() from 'net' overlapped with the new support for returning congestion notifications from BPF programs. In order to handle this I had to take the dev_loopback_xmit() calls out of the switch statement. The aquantia driver conflicts were simple overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-26ipv6: constify rt6_nexthop()Nicolas Dichtel
There is no functional change in this patch, it only prepares the next one. rt6_nexthop() will be used by ip6_dst_lookup_neigh(), which uses const variables. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Reported-by: kbuild test robot <lkp@intel.com> Acked-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-24ipv6: Dump route exceptions if requestedStefano Brivio
Since commit 2b760fcf5cfb ("ipv6: hook up exception table to store dst cache"), route exceptions reside in a separate hash table, and won't be found by walking the FIB, so they won't be dumped to userspace on a RTM_GETROUTE message. This causes 'ip -6 route list cache' and 'ip -6 route flush cache' to have no function anymore: # ip -6 route get fc00:3::1 fc00:3::1 via fc00:1::2 dev veth_A-R1 src fc00:1::1 metric 1024 expires 539sec mtu 1400 pref medium # ip -6 route get fc00:4::1 fc00:4::1 via fc00:2::2 dev veth_A-R2 src fc00:2::1 metric 1024 expires 536sec mtu 1500 pref medium # ip -6 route list cache # ip -6 route flush cache # ip -6 route get fc00:3::1 fc00:3::1 via fc00:1::2 dev veth_A-R1 src fc00:1::1 metric 1024 expires 520sec mtu 1400 pref medium # ip -6 route get fc00:4::1 fc00:4::1 via fc00:2::2 dev veth_A-R2 src fc00:2::1 metric 1024 expires 519sec mtu 1500 pref medium because iproute2 lists cached routes using RTM_GETROUTE, and flushes them by listing all the routes, and deleting them with RTM_DELROUTE one by one. If cached routes are requested using the RTM_F_CLONED flag together with strict checking, or if no strict checking is requested (and hence we can't consistently apply filters), look up exceptions in the hash table associated with the current fib6_info in rt6_dump_route(), and, if present and not expired, add them to the dump. We might be unable to dump all the entries for a given node in a single message, so keep track of how many entries were handled for the current node in fib6_walker, and skip that amount in case we start from the same partially dumped node. When a partial dump restarts, as the starting node might change when 'sernum' changes, we have no guarantee that we need to skip the same amount of in-node entries. Therefore, we need two counters, and we need to zero the in-node counter if the node from which the dump is resumed differs. Note that, with the current version of iproute2, this only fixes the 'ip -6 route list cache': on a flush command, iproute2 doesn't pass RTM_F_CLONED and, due to this inconsistency, 'ip -6 route flush cache' is still unable to fetch the routes to be flushed. This will be addressed in a patch for iproute2. To flush cached routes, a procfs entry could be introduced instead: that's how it works for IPv4. We already have a rt6_flush_exception() function ready to be wired to it. However, this would not solve the issue for listing. Versions of iproute2 and kernel tested: iproute2 kernel 4.14.0 4.15.0 4.19.0 5.0.0 5.1.0 5.1.0, patched 3.18 list + + + + + + flush + + + + + + 4.4 list + + + + + + flush + + + + + + 4.9 list + + + + + + flush + + + + + + 4.14 list + + + + + + flush + + + + + + 4.15 list flush 4.19 list flush 5.0 list flush 5.1 list flush with list + + + + + + fix flush + + + + v7: - Explain usage of "skip" counters in commit message (suggested by David Ahern) v6: - Rebase onto net-next, use recently introduced nexthop walker - Make rt6_nh_dump_exceptions() a separate function (suggested by David Ahern) v5: - Use dump_routes and dump_exceptions from filter, ignore NLM_F_MATCH, update test results (flushing works with iproute2 < 5.0.0 now) v4: - Split NLM_F_MATCH and strict check handling in separate patches - Filter routes using RTM_F_CLONED: if it's not set, only return non-cached routes, and if it's set, only return cached routes: change requested by David Ahern and Martin Lau. This implies that iproute2 needs a separate patch to be able to flush IPv6 cached routes. This is not ideal because we can't fix the breakage caused by 2b760fcf5cfb entirely in kernel. However, two years have passed since then, and this makes it more tolerable v3: - More descriptive comment about expired exceptions in rt6_dump_route() - Swap return values of rt6_dump_route() (suggested by Martin Lau) - Don't zero skip_in_node in case we don't dump anything in a given pass (also suggested by Martin Lau) - Remove check on RTM_F_CLONED altogether: in the current UAPI semantic, it's just a flag to indicate the route was cloned, not to filter on routes v2: Add tracking of number of entries to be skipped in current node after a partial dump. As we restart from the same node, if not all the exceptions for a given node fit in a single message, the dump will not terminate, as suggested by Martin Lau. This is a concrete possibility, setting up a big number of exceptions for the same route actually causes the issue, suggested by David Ahern. Reported-by: Jianlin Shi <jishi@redhat.com> Fixes: 2b760fcf5cfb ("ipv6: hook up exception table to store dst cache") Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-23ipv6: convert major tx path to use RT6_LOOKUP_F_DST_NOREFWei Wang
For tx path, in most cases, we still have to take refcnt on the dst cause the caller is caching the dst somewhere. But it still is beneficial to make use of RT6_LOOKUP_F_DST_NOREF flag while doing the route lookup. It is cause this flag prevents manipulating refcnt on net->ipv6.ip6_null_entry when doing fib6_rule_lookup() to traverse each routing table. The null_entry is a shared object and constant updates on it cause false sharing. We converted the current major lookup function ip6_route_output_flags() to make use of RT6_LOOKUP_F_DST_NOREF. Together with the change in the rx path, we see noticable performance boost: I ran synflood tests between 2 hosts under the same switch. Both hosts have 20G mlx NIC, and 8 tx/rx queues. Sender sends pure SYN flood with random src IPs and ports using trafgen. Receiver has a simple TCP listener on the target port. Both hosts have multiple custom rules: - For incoming packets, only local table is traversed. - For outgoing packets, 3 tables are traversed to find the route. The packet processing rate on the receiver is as follows: - Before the fix: 3.78Mpps - After the fix: 5.50Mpps Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-23ipv6: honor RT6_LOOKUP_F_DST_NOREF in rule lookup logicWei Wang
This patch specifically converts the rule lookup logic to honor this flag and not release refcnt when traversing each rule and calling lookup() on each routing table. Similar to previous patch, we also need some special handling of dst entries in uncached list because there is always 1 refcnt taken for them even if RT6_LOOKUP_F_DST_NOREF flag is set. Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-23ipv6: introduce RT6_LOOKUP_F_DST_NOREF flag in ip6_pol_route()Wei Wang
This new flag is to instruct the route lookup function to not take refcnt on the dst entry. The user which does route lookup with this flag must properly use rcu protection. ip6_pol_route() is the major route lookup function for both tx and rx path. In this function: Do not take refcnt on dst if RT6_LOOKUP_F_DST_NOREF flag is set, and directly return the route entry. The caller should be holding rcu lock when using this flag, and decide whether to take refcnt or not. One note on the dst cache in the uncached_list: As uncached_list does not consume refcnt, one refcnt is always returned back to the caller even if RT6_LOOKUP_F_DST_NOREF flag is set. Uncached dst is only possible in the output path. So in such call path, caller MUST check if the dst is in the uncached_list before assuming that there is no refcnt taken on the returned dst. Signed-off-by: Wei Wang <weiwan@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Acked-by: Mahesh Bandewar <maheshb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-04ipv6: Plumb support for nexthop object in a fib6_infoDavid Ahern
Add struct nexthop and nh_list list_head to fib6_info. nh_list is the fib6_info side of the nexthop <-> fib_info relationship. Since a fib6_info referencing a nexthop object can not have 'sibling' entries (the old way of doing multipath routes), the nh_list is a union with fib6_siblings. Add f6i_list list_head to 'struct nexthop' to track fib6_info entries using a nexthop instance. Update __remove_nexthop_fib to walk f6_list and delete fib entries using the nexthop. Add a few nexthop helpers for use when a nexthop is added to fib6_info: - nexthop_fib6_nh - return first fib6_nh in a nexthop object - fib6_info_nh_dev moved to nexthop.h and updated to use nexthop_fib6_nh if the fib6_info references a nexthop object - nexthop_path_fib6_result - similar to ipv4, select a path within a multipath nexthop object. If the nexthop is a blackhole, set fib6_result type to RTN_BLACKHOLE, and set the REJECT flag Update the fib6_info references to check for nh and take a different path as needed: - rt6_qualify_for_ecmp - if a fib entry uses a nexthop object it can NOT be coalesced with other fib entries into a multipath route - rt6_duplicate_nexthop - use nexthop_cmp if either fib6_info references a nexthop - addrconf (host routes), RA's and info entries (anything configured via ndisc) does not use nexthop objects - fib6_info_destroy_rcu - put reference to nexthop object - fib6_purge_rt - drop fib6_info from f6i_list - fib6_select_path - update to use the new nexthop_path_fib6_result when fib entry uses a nexthop object - rt6_device_match - update to catch use of nexthop object as a blackhole and set fib6_type and flags. - ip6_route_info_create - don't add space for fib6_nh if fib entry is going to reference a nexthop object, take a reference to nexthop object, disallow use of source routing - rt6_nlmsg_size - add space for RTA_NH_ID - add rt6_fill_node_nexthop to add nexthop data on a dump As with ipv4, most of the changes push existing code into the else branch of whether the fib entry uses a nexthop object. Update the nexthop code to walk f6i_list on a nexthop deleted to remove fib entries referencing it. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-24ipv6: Make fib6_nh optional at the end of fib6_infoDavid Ahern
Move fib6_nh to the end of fib6_info and make it an array of size 0. Pass a flag to fib6_info_alloc indicating if the allocation needs to add space for a fib6_nh. The current code path always has a fib6_nh allocated with a fib6_info; with nexthop objects they will be separate. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-23net: Change nhc_flags to unsigned charDavid Ahern
nhc_flags holds the RTNH_F flags for a given nexthop (fib{6}_nh). All of the RTNH_F_ flags fit in an unsigned char, and since the API to userspace (rtnh_flags and lower byte of rtm_flags) is 1 byte it can not grow. Make nhc_flags in fib_nh_common an unsigned char and shrink the size of the struct by 8, from 56 to 48 bytes. Update the flags arguments for up netdevice events and fib_nexthop_info which determines the RTNH_F flags to return on a dump/event. The RTNH_F flags are passed in the lower byte of rtm_flags which is an unsigned int so use a temp variable for the flags to fib_nexthop_info and combine with rtm_flags in the caller. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-21ipv6: Restore RTF_ADDRCONF check in rt6_qualify_for_ecmpDavid Ahern
The RTF_ADDRCONF flag filters out routes added by RA's in determining which routes can be appended to an existing one to create a multipath route. Restore the flag check and add a comment to document the RA piece. Fixes: 4e54507ab1a9 ("ipv6: Simplify rt6_qualify_for_ecmp") Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-21ipv6: Simplify rt6_qualify_for_ecmpDavid Ahern
After commit c7a1ce397ada ("ipv6: Change addrconf_f6i_alloc to use ip6_route_info_create"), the gateway is no longer filled in for fib6_nh structs in a prefix route. Accordingly, the RTF_ADDRCONF flag check can be dropped from the 'rt6_qualify_for_ecmp'. Further, RTF_DYNAMIC is only set in rt6_info instances, so it can be removed from the check as well. This reduces rt6_qualify_for_ecmp and the mlxsw version to just checking if the nexthop has a gateway which is the real indication of whether entries can be coalesced into a multipath route. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-17ipv6: Pass fib6_result to ip6_mtu_from_fib6 and fib6_mtuDavid Ahern
Change ip6_mtu_from_fib6 and fib6_mtu to take a fib6_result over a fib6_info. Update both to use the fib6_nh from fib6_result. Since the signature of ip6_mtu_from_fib6 is already changing, add const to daddr and saddr. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-08net: Replace nhc_has_gw with nhc_gw_familyDavid Ahern
Allow the gateway in a fib_nh_common to be from a different address family than the outer fib{6}_nh. To that end, replace nhc_has_gw with nhc_gw_family and update users of nhc_has_gw to check nhc_gw_family. Now nhc_family is used to know if the nh_common is part of a fib_nh or fib6_nh (used for container_of to get to route family specific data), and nhc_gw_family represents the address family for the gateway. Signed-off-by: David Ahern <dsahern@gmail.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-29ipv6: Rename fib6_nh entriesDavid Ahern
Rename fib6_nh entries that will be moved to a fib_nh_common struct. Specifically, the device, gateway, flags, and lwtstate are common with all nexthop definitions. In some places new temporary variables are declared or local variables renamed to maintain line lengths. Rename only; no functional change intended. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-29ipv6: Move gateway checks to a fib6_nh settingDavid Ahern
The gateway setting is not per fib6_info entry but per-fib6_nh. Add a new fib_nh_has_gw flag to fib6_nh and convert references to RTF_GATEWAY to the new flag. For IPv6 address the flag is cheaper than checking that nh_gw is non-0 like IPv4 does. While this increases fib6_nh by 8-bytes, the effective allocation size of a fib6_info is unchanged. The 8 bytes is recovered later with a fib_nh_common change. Signed-off-by: David Ahern <dsahern@gmail.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-16net: Add struct for fib dump filterDavid Ahern
Add struct fib_dump_filter for options on limiting which routes are returned in a dump request. The current list is table id, protocol, route type, rtm_flags and nexthop device index. struct net is needed to lookup the net_device from the index. Declare the filter for each route dump handler and plumb the new arguments from dump handlers to ip_valid_fib_dump_req. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-02net: remove 1 always zero parameter from ip6_redirect_no_header()Maciej Żenczykowski
(the parameter in question is mark) Signed-off-by: Maciej Żenczykowski <maze@google.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-04net/ipv6: Revert attempt to simplify route replace and appendDavid Ahern
NetworkManager likes to manage linklocal prefix routes and does so with the NLM_F_APPEND flag, breaking attempts to simplify the IPv6 route code and by extension enable multipath routes with device only nexthops. Revert f34436a43092 and these followup patches: 6eba08c3626b ("ipv6: Only emit append events for appended routes"). ce45bded6435 ("mlxsw: spectrum_router: Align with new route replace logic") 53b562df8c20 ("mlxsw: spectrum_router: Allow appending to dev-only routes") Update the fib_tests cases to reflect the old behavior. Fixes: f34436a43092 ("net/ipv6: Simplify route replace and appending into multipath route") Signed-off-by: David Ahern <dsahern@gmail.com>
2018-05-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller
Alexei Starovoitov says: ==================== pull-request: bpf-next 2018-05-24 The following pull-request contains BPF updates for your *net-next* tree. The main changes are: 1) Björn Töpel cleans up AF_XDP (removes rebind, explicit cache alignment from uapi, etc). 2) David Ahern adds mtu checks to bpf_ipv{4,6}_fib_lookup() helpers. 3) Jesper Dangaard Brouer adds bulking support to ndo_xdp_xmit. 4) Jiong Wang adds support for indirect and arithmetic shifts to NFP 5) Martin KaFai Lau cleans up BTF uapi and makes the btf_header extensible. 6) Mathieu Xhonneux adds an End.BPF action to seg6local with BPF helpers allowing to edit/grow/shrink a SRH and apply on a packet generic SRv6 actions. 7) Sandipan Das adds support for bpf2bpf function calls in ppc64 JIT. 8) Yonghong Song adds BPF_TASK_FD_QUERY command for introspection of tracing events. 9) other misc fixes from Gustavo A. R. Silva, Sirio Balmelli, John Fastabend, and Magnus Karlsson ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-22net/ipv6: Simplify route replace and appending into multipath routeDavid Ahern
Bring consistency to ipv6 route replace and append semantics. Remove rt6_qualify_for_ecmp which is just guess work. It fails in 2 cases: 1. can not replace a route with a reject route. Existing code appends a new route instead of replacing the existing one. 2. can not have a multipath route where a leg uses a dev only nexthop Existing use cases affected by this change: 1. adding a route with existing prefix and metric using NLM_F_CREATE without NLM_F_APPEND or NLM_F_EXCL (ie., what iproute2 calls 'prepend'). Existing code auto-determines that the new nexthop can be appended to an existing route to create a multipath route. This change breaks that by requiring the APPEND flag for the new route to be added to an existing one. Instead the prepend just adds another route entry. 2. route replace. Existing code replaces first matching multipath route if new route is multipath capable and fallback to first matching non-ECMP route (reject or dev only route) in case one isn't available. New behavior replaces first matching route. (Thanks to Ido for spotting this one) Note: Newer iproute2 is needed to display multipath routes with a dev-only nexthop. This is due to a bug in iproute2 and parsing nexthops. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-22net/ipv6: Add helper to return path MTU based on fib resultDavid Ahern
Determine path MTU from a FIB lookup result. Logic is based on ip6_dst_mtu_forward plus lookup of nexthop exception. Add ip6_dst_mtu_forward to ipv6_stubs to handle access by core bpf code. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2018-05-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-nextDavid S. Miller
Pablo Neira Ayuso says: ==================== Netfilter/IPVS updates for net-next The following patchset contains Netfilter/IPVS updates for your net-next tree, more relevant updates in this batch are: 1) Add Maglev support to IPVS. Moreover, store lastest server weight in IPVS since this is needed by maglev, patches from from Inju Song. 2) Preparation works to add iptables flowtable support, patches from Felix Fietkau. 3) Hand over flows back to conntrack slow path in case of TCP RST/FIN packet is seen via new teardown state, also from Felix. 4) Add support for extended netlink error reporting for nf_tables. 5) Support for larger timeouts that 23 days in nf_tables, patch from Florian Westphal. 6) Always set an upper limit to dynamic sets, also from Florian. 7) Allow number generator to make map lookups, from Laura Garcia. 8) Use hash_32() instead of opencode hashing in IPVS, from Vicent Bernat. 9) Extend ip6tables SRH match to support previous, next and last SID, from Ahmed Abdelsalam. 10) Move Passive OS fingerprint nf_osf.c, from Fernando Fernandez. 11) Expose nf_conntrack_max through ctnetlink, from Florent Fourcot. 12) Several housekeeping patches for xt_NFLOG, x_tables and ebtables, from Taehee Yoo. 13) Unify meta bridge with core nft_meta, then make nft_meta built-in. Make rt and exthdr built-in too, again from Florian. 14) Missing initialization of tbl->entries in IPVS, from Cong Wang. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-21ipv6: make ip6_dst_mtu_forward inlineFelix Fietkau
Just like ip_dst_mtu_maybe_forward(), to avoid a dependency with ipv6.ko. Signed-off-by: Felix Fietkau <nbd@nbd.name> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-04-19net/ipv6: Remove compare of fib6_idev from rt6_duplicate_nexthopDavid Ahern
After 4832c30d5458 ("net: ipv6: put host and anycast routes on device with address") the comparison of idev does not add value since it correlates to the nexthop device which is already compared. Remove the idev comparison. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-19net/ipv6: Change ip6_route_get_saddr to get dev from routeDavid Ahern
Prior to 4832c30d5458 ("net: ipv6: put host and anycast routes on device with address") host routes and anycast routes were installed with the device set to loopback (or VRF device once that feature was added). In the older code dst.dev was set to loopback (needed for packet tx) and rt6i_idev was used to denote the actual interface. Commit 4832c30d5458 changed the code to have dst.dev pointing to the real device with the switch to lo or vrf device done on dst clones. As a consequence of this change ip6_route_get_saddr can just pass the nexthop device to ipv6_dev_get_saddr. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-19net/ipv6: Rename addrconf_dst_allocDavid Ahern
addrconf_dst_alloc now returns a fib6_info. Update the name and its users to reflect the change. Rename only; no functional change intended. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-19net/ipv6: Rename fib6_info struct elementsDavid Ahern
Change the prefix for fib6_info struct elements from rt6i_ to fib6_. rt6i_pcpu and rt6i_exception_bucket are left as is given that they point to rt6_info entries. Rename only; not functional change intended. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-17net/ipv6: Flip FIB entries to fib6_infoDavid Ahern
Convert all code paths referencing a FIB entry from rt6_info to fib6_info. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-17net/ipv6: separate handling of FIB entries from dst based routesDavid Ahern
Last step before flipping the data type for FIB entries: - use fib6_info_alloc to create FIB entries in ip6_route_info_create and addrconf_dst_alloc - use fib6_info_release in place of dst_release, ip6_rt_put and rt6_release - remove the dst_hold before calling __ip6_ins_rt or ip6_del_rt - when purging routes, drop per-cpu routes - replace inc and dec of rt6i_ref with fib6_info_hold and fib6_info_release - use rt->from since it points to the FIB entry - drop references to exception bucket, fib6_metrics and per-cpu from dst entries (those are relevant for fib entries only) Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>