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path: root/net/ipv4/route.c
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2021-08-05net: Remove redundant if statementsYajun Deng
The 'if (dev)' statement already move into dev_{put , hold}, so remove redundant if statements. Signed-off-by: Yajun Deng <yajun.deng@linux.dev> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-03net: Keep vertical alignmentYajun Deng
Those files under /proc/net/stat/ don't have vertical alignment, it looks very difficult. Modify the seq_printf statement, keep vertical alignment. v2: - Use seq_puts() and seq_printf() correctly. Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Yajun Deng <yajun.deng@linux.dev> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21net: ipv4: Consolidate ipv4_mtu and ip_dst_mtu_maybe_forwardVadim Fedorenko
Consolidate IPv4 MTU code the same way it is done in IPv6 to have code aligned in both address families Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-29Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Trivial conflict in net/netfilter/nf_tables_api.c. Duplicate fix in tools/testing/selftests/net/devlink_port_split.py - take the net-next version. skmsg, and L4 bpf - keep the bpf code but remove the flags and err params. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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>
2021-06-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Trivial conflicts in net/can/isotp.c and tools/testing/selftests/net/mptcp/mptcp_connect.sh scaled_ppm_to_ppb() was moved from drivers/ptp/ptp_clock.c to include/linux/ptp_clock_kernel.h in -next so re-apply the fix there. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-06-14ipv4: Fix device used for dst_alloc with local routesDavid Ahern
Oliver reported a use case where deleting a VRF device can hang waiting for the refcnt to drop to 0. The root cause is that the dst is allocated against the VRF device but cached on the loopback device. The use case (added to the selftests) has an implicit VRF crossing due to the ordering of the FIB rules (lookup local is before the l3mdev rule, but the problem occurs even if the FIB rules are re-ordered with local after l3mdev because the VRF table does not have a default route to terminate the lookup). The end result is is that the FIB lookup returns the loopback device as the nexthop, but the ingress device is in a VRF. The mismatch causes the dst alloc against the VRF device but then cached on the loopback. The fix is to bring the trick used for IPv6 (see ip6_rt_get_dev_rcu): pick the dst alloc device based the fib lookup result but with checks that the result has a nexthop device (e.g., not an unreachable or prohibit entry). Fixes: f5a0aab84b74 ("net: ipv4: dst for local input routes should use l3mdev if relevant") Reported-by: Oliver Herms <oliver.peter.herms@gmail.com> Signed-off-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-18ipv4: Add custom multipath hash policyIdo Schimmel
Add a new multipath hash policy where the packet fields used for hash calculation are determined by user space via the fib_multipath_hash_fields sysctl that was introduced in the previous patch. The current set of available packet fields includes both outer and inner fields, which requires two invocations of the flow dissector. Avoid unnecessary dissection of the outer or inner flows by skipping dissection if none of the outer or inner fields are required. In accordance with the existing policies, when an skb is not available, packet fields are extracted from the provided flow key. In which case, only outer fields are considered. Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-18ipv4: Calculate multipath hash inside switch statementIdo Schimmel
A subsequent patch will add another multipath hash policy where the multipath hash is calculated directly by the policy specific code and not outside of the switch statement. Prepare for this change by moving the multipath hash calculation inside the switch statement. No functional changes intended. Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-25Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-24inet: use bigger hash table for IP ID generationEric Dumazet
In commit 73f156a6e8c1 ("inetpeer: get rid of ip_id_count") I used a very small hash table that could be abused by patient attackers to reveal sensitive information. Switch to a dynamic sizing, depending on RAM size. Typical big hosts will now use 128x more storage (2 MB) to get a similar increase in security and reduction of hash collisions. As a bonus, use of alloc_large_system_hash() spreads allocated memory among all NUMA nodes. Fixes: 73f156a6e8c1 ("inetpeer: get rid of ip_id_count") Reported-by: Amit Klein <aksecurity@gmail.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willy Tarreau <w@1wt.eu> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-16net: ipv4: route.c: simplify procfs codeYejune Deng
proc_creat_seq() that directly take a struct seq_operations, and deal with network namespaces in ->open. Signed-off-by: Yejune Deng <yejune.deng@gmail.com> Reviewed-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-12net: ipv4: route.c: Fix indentation of multi line comment.Shubhankar Kuranagatti
All comment lines inside the comment block have been aligned. Every line of comment starts with a * (uniformity in code). Signed-off-by: Shubhankar Kuranagatti <shubhankarvk@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-10net: ipv4: route.c: fix space before tabShubhankar Kuranagatti
The extra space before tab space has been removed. Signed-off-by: Shubhankar Kuranagatti <shubhankarvk@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-03-10net: Consolidate common blackhole dst opsDaniel Borkmann
Move generic blackhole dst ops to the core and use them from both ipv4_dst_blackhole_ops and ip6_dst_blackhole_ops where possible. No functional change otherwise. We need these also in other locations and having to define them over and over again is not great. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-08IPv4: Add "offload failed" indication to routesAmit Cohen
After installing a route to the kernel, user space receives an acknowledgment, which means the route was installed in the kernel, but not necessarily in hardware. The asynchronous nature of route installation in hardware can lead to a routing daemon advertising a route before it was actually installed in hardware. This can result in packet loss or mis-routed packets until the route is installed in hardware. To avoid such cases, previous patch set added the ability to emit RTM_NEWROUTE notifications whenever RTM_F_OFFLOAD/RTM_F_TRAP flags are changed, this behavior is controlled by sysctl. With the above mentioned behavior, it is possible to know from user-space if the route was offloaded, but if the offload fails there is no indication to user-space. Following a failure, a routing daemon will wait indefinitely for a notification that will never come. This patch adds an "offload_failed" indication to IPv4 routes, so that users will have better visibility into the offload process. 'struct fib_alias', and 'struct fib_rt_info' are extended with new field that indicates if route offload failed. Note that the new field is added using unused bit and therefore there is no need to increase structs size. Signed-off-by: Amit Cohen <amcohen@nvidia.com> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-02-04net: fix building errors on powerpc when CONFIG_RETPOLINE is not setBrian Vazquez
This commit fixes the errores reported when building for powerpc: ERROR: modpost: "ip6_dst_check" [vmlinux] is a static EXPORT_SYMBOL ERROR: modpost: "ipv4_dst_check" [vmlinux] is a static EXPORT_SYMBOL ERROR: modpost: "ipv4_mtu" [vmlinux] is a static EXPORT_SYMBOL ERROR: modpost: "ip6_mtu" [vmlinux] is a static EXPORT_SYMBOL Fixes: f67fbeaebdc0 ("net: use indirect call helpers for dst_mtu") Fixes: bbd807dfbf20 ("net: indirect call helpers for ipv4/ipv6 dst_check functions") Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Brian Vazquez <brianvv@google.com> Link: https://lore.kernel.org/r/20210204181839.558951-2-brianvv@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-02-03net: indirect call helpers for ipv4/ipv6 dst_check functionsBrian Vazquez
This patch avoids the indirect call for the common case: ip6_dst_check and ipv4_dst_check Signed-off-by: Brian Vazquez <brianvv@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-02-03net: use indirect call helpers for dst_mtuBrian Vazquez
This patch avoids the indirect call for the common case: ip6_mtu and ipv4_mtu Signed-off-by: Brian Vazquez <brianvv@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-03Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Conflicts: drivers/net/ethernet/ibm/ibmvnic.c Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-28ipv4: Fix tos mask in inet_rtm_getroute()Guillaume Nault
When inet_rtm_getroute() was converted to use the RCU variants of ip_route_input() and ip_route_output_key(), the TOS parameters stopped being masked with IPTOS_RT_MASK before doing the route lookup. As a result, "ip route get" can return a different route than what would be used when sending real packets. For example: $ ip route add 192.0.2.11/32 dev eth0 $ ip route add unreachable 192.0.2.11/32 tos 2 $ ip route get 192.0.2.11 tos 2 RTNETLINK answers: No route to host But, packets with TOS 2 (ECT(0) if interpreted as an ECN bit) would actually be routed using the first route: $ ping -c 1 -Q 2 192.0.2.11 PING 192.0.2.11 (192.0.2.11) 56(84) bytes of data. 64 bytes from 192.0.2.11: icmp_seq=1 ttl=64 time=0.173 ms --- 192.0.2.11 ping statistics --- 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 0.173/0.173/0.173/0.000 ms This patch re-applies IPTOS_RT_MASK in inet_rtm_getroute(), to return results consistent with real route lookups. Fixes: 3765d35ed8b9 ("net: ipv4: Convert inet_rtm_getroute to rcu versions of route lookup") Signed-off-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/b2d237d08317ca55926add9654a48409ac1b8f5b.1606412894.git.gnault@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-14IPv4: RTM_GETROUTE: Add RTA_ENCAP to resultOliver Herms
This patch adds an IPv4 routes encapsulation attribute to the result of netlink RTM_GETROUTE requests (e.g. ip route get 192.0.2.1). Signed-off-by: Oliver Herms <oliver.peter.herms@gmail.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20201113085517.GA1307262@tws Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-11net: evaluate net.ipvX.conf.all.disable_policy and disable_xfrmVincent Bernat
The disable_policy and disable_xfrm are a per-interface sysctl to disable IPsec policy or encryption on an interface. However, while a "all" variant is exposed, it was a noop since it was never evaluated. We use the usual "or" logic for this kind of sysctls. Signed-off-by: Vincent Bernat <vincent@bernat.ch> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-10-15Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Minor conflicts in net/mptcp/protocol.h and tools/testing/selftests/net/Makefile. In both cases code was added on both sides in the same place so just keep both. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-10-10ipv4: Restore flowi4_oif update before call to xfrm_lookup_routeDavid Ahern
Tobias reported regressions in IPsec tests following the patch referenced by the Fixes tag below. The root cause is dropping the reset of the flowi4_oif after the fib_lookup. Apparently it is needed for xfrm cases, so restore the oif update to ip_route_output_flow right before the call to xfrm_lookup_route. Fixes: 2fbc6e89b2f1 ("ipv4: Update exception handling for multipath routes via same device") Reported-by: Tobias Brunner <tobias@strongswan.org> Signed-off-by: David Ahern <dsahern@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-09-22Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
Two minor conflicts: 1) net/ipv4/route.c, adding a new local variable while moving another local variable and removing it's initial assignment. 2) drivers/net/dsa/microchip/ksz9477.c, overlapping changes. One pretty prints the port mode differently, whilst another changes the driver to try and obtain the port mode from the port node rather than the switch node. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-15ipv4: Update exception handling for multipath routes via same deviceDavid Ahern
Kfir reported that pmtu exceptions are not created properly for deployments where multipath routes use the same device. After some digging I see 2 compounding problems: 1. ip_route_output_key_hash_rcu is updating the flowi4_oif *after* the route lookup. This is the second use case where this has been a problem (the first is related to use of vti devices with VRF). I can not find any reason for the oif to be changed after the lookup; the code goes back to the start of git. It does not seem logical so remove it. 2. fib_lookups for exceptions do not call fib_select_path to handle multipath route selection based on the hash. The end result is that the fib_lookup used to add the exception always creates it based using the first leg of the route. An example topology showing the problem: | host1 +------+ | eth0 | .209 +------+ | +------+ switch | br0 | +------+ | +---------+---------+ | host2 | host3 +------+ +------+ | eth0 | .250 | eth0 | 192.168.252.252 +------+ +------+ +-----+ +-----+ | vti | .2 | vti | 192.168.247.3 +-----+ +-----+ \ / ================================= tunnels 192.168.247.1/24 for h in host1 host2 host3; do ip netns add ${h} ip -netns ${h} link set lo up ip netns exec ${h} sysctl -wq net.ipv4.ip_forward=1 done ip netns add switch ip -netns switch li set lo up ip -netns switch link add br0 type bridge stp 0 ip -netns switch link set br0 up for n in 1 2 3; do ip -netns switch link add eth-sw type veth peer name eth-h${n} ip -netns switch li set eth-h${n} master br0 up ip -netns switch li set eth-sw netns host${n} name eth0 done ip -netns host1 addr add 192.168.252.209/24 dev eth0 ip -netns host1 link set dev eth0 up ip -netns host1 route add 192.168.247.0/24 \ nexthop via 192.168.252.250 dev eth0 nexthop via 192.168.252.252 dev eth0 ip -netns host2 addr add 192.168.252.250/24 dev eth0 ip -netns host2 link set dev eth0 up ip -netns host2 addr add 192.168.252.252/24 dev eth0 ip -netns host3 link set dev eth0 up ip netns add tunnel ip -netns tunnel li set lo up ip -netns tunnel li add br0 type bridge ip -netns tunnel li set br0 up for n in $(seq 11 20); do ip -netns tunnel addr add dev br0 192.168.247.${n}/24 done for n in 2 3 do ip -netns tunnel link add vti${n} type veth peer name eth${n} ip -netns tunnel link set eth${n} mtu 1360 master br0 up ip -netns tunnel link set vti${n} netns host${n} mtu 1360 up ip -netns host${n} addr add dev vti${n} 192.168.247.${n}/24 done ip -netns tunnel ro add default nexthop via 192.168.247.2 nexthop via 192.168.247.3 ip netns exec host1 ping -M do -s 1400 -c3 -I 192.168.252.209 192.168.247.11 ip netns exec host1 ping -M do -s 1400 -c3 -I 192.168.252.209 192.168.247.15 ip -netns host1 ro ls cache Before this patch the cache always shows exceptions against the first leg in the multipath route; 192.168.252.250 per this example. Since the hash has an initial random seed, you may need to vary the final octet more than what is listed. In my tests, using addresses between 11 and 19 usually found 1 that used both legs. With this patch, the cache will have exceptions for both legs. Fixes: 4895c771c7f0 ("ipv4: Add FIB nexthop exceptions") Reported-by: Kfir Itzhak <mastertheknife@gmail.com> Signed-off-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-14ipv4: Initialize flowi4_multipath_hash in data pathDavid Ahern
flowi4_multipath_hash was added by the commit referenced below for tunnels. Unfortunately, the patch did not initialize the new field for several fast path lookups that do not initialize the entire flow struct to 0. Fix those locations. Currently, flowi4_multipath_hash is random garbage and affects the hash value computed by fib_multipath_hash for multipath selection. Fixes: 24ba14406c5c ("route: Add multipath_hash in flowi_common to make user-define hash") Signed-off-by: David Ahern <dsahern@gmail.com> Cc: wenxu <wenxu@ucloud.cn> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-31net: clean up codestyleMiaohe Lin
This is a pure codestyle cleanup patch. No functional change intended. Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-25net: clean up codestyle for net/ipv4Miaohe Lin
This is a pure codestyle cleanup patch. Also add a blank line after declarations as warned by checkpatch.pl. Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-25net: gain ipv4 mtu when mtu is not lockedMiaohe Lin
When mtu is locked, we should not obtain ipv4 mtu as we return immediately in this case and leave acquired ipv4 mtu unused. Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-04ipv4: route: Ignore output interface in FIB lookup for PMTU routeStefano Brivio
Currently, processes sending traffic to a local bridge with an encapsulation device as a port don't get ICMP errors if they exceed the PMTU of the encapsulated link. David Ahern suggested this as a hack, but it actually looks like the correct solution: when we update the PMTU for a given destination by means of updating or creating a route exception, the encapsulation might trigger this because of PMTU discovery happening either on the encapsulation device itself, or its lower layer. This happens on bridged encapsulations only. The output interface shouldn't matter, because we already have a valid destination. Drop the output interface restriction from the associated route lookup. For UDP tunnels, we will now have a route exception created for the encapsulation itself, with a MTU value reflecting its headroom, which allows a bridge forwarding IP packets originated locally to deliver errors back to the sending socket. The behaviour is now consistent with IPv6 and verified with selftests pmtu_ipv{4,6}_br_{geneve,vxlan}{4,6}_exception introduced later in this series. v2: - reset output interface only for bridge ports (David Ahern) - add and use netif_is_any_bridge_port() helper (David Ahern) Suggested-by: David Ahern <dsahern@gmail.com> Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-27net: ipv4: Fix wrong type conversion from hint to rt in ip_route_use_hint()Miaohe Lin
We can't cast sk_buff to rtable by (struct rtable *)hint. Use skb_rtable(). Fixes: 02b24941619f ("ipv4: use dst hint for ipv4 list receive") Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
The MSCC bug fix in 'net' had to be slightly adjusted because the register accesses are done slightly differently in net-next. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-17net: revert "net: get rid of an signed integer overflow in ip_idents_reserve()"Yuqi Jin
Commit adb03115f459 ("net: get rid of an signed integer overflow in ip_idents_reserve()") used atomic_cmpxchg to replace "atomic_add_return" inside the function "ip_idents_reserve". The reason was to avoid UBSAN warning. However, this change has caused performance degrade and in GCC-8, fno-strict-overflow is now mapped to -fwrapv -fwrapv-pointer and signed integer overflow is now undefined by default at all optimization levels[1]. Moreover, it was a bug in UBSAN vs -fwrapv /-fno-strict-overflow, so Let's revert it safely. [1] https://gcc.gnu.org/gcc-8/changes.html Suggested-by: Peter Zijlstra <peterz@infradead.org> Suggested-by: Eric Dumazet <edumazet@google.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Jiri Pirko <jiri@resnulli.us> Cc: Arvind Sankar <nivedita@alum.mit.edu> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Eric Dumazet <edumazet@google.com> Cc: Jiong Wang <jiongwang@huawei.com> Signed-off-by: Yuqi Jin <jinyuqi@huawei.com> Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-15Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
Move the bpf verifier trace check into the new switch statement in HEAD. Resolve the overlapping changes in hinic, where bug fixes overlap the addition of VF support. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-08net: ipv4: really enforce backoff for redirectsPaolo Abeni
In commit b406472b5ad7 ("net: ipv4: avoid mixed n_redirects and rate_tokens usage") I missed the fact that a 0 'rate_tokens' will bypass the backoff algorithm. Since rate_tokens is cleared after a redirect silence, and never incremented on redirects, if the host keeps receiving packets requiring redirect it will reply ignoring the backoff. Additionally, the 'rate_last' field will be updated with the cadence of the ingress packet requiring redirect. If that rate is high enough, that will prevent the host from generating any other kind of ICMP messages The check for a zero 'rate_tokens' value was likely a shortcut to avoid the more complex backoff algorithm after a redirect silence period. Address the issue checking for 'n_redirects' instead, which is incremented on successful redirect, and does not interfere with other ICMP replies. Fixes: b406472b5ad7 ("net: ipv4: avoid mixed n_redirects and rate_tokens usage") Reported-and-tested-by: Colin Walters <walters@redhat.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-04-27sysctl: pass kernel pointers to ->proc_handlerChristoph Hellwig
Instead of having all the sysctl handlers deal with user pointers, which is rather hairy in terms of the BPF interaction, copy the input to and from userspace in common code. This also means that the strings are always NUL-terminated by the common code, making the API a little bit safer. As most handler just pass through the data to one of the common handlers a lot of the changes are mechnical. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-03-23Remove DST_HOSTDavid Laight
Previous changes to the IP routing code have removed all the tests for the DS_HOST route flag. Remove the flags and all the code that sets it. Signed-off-by: David Laight <david.laight@aculab.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-24net: UDP tunnel encapsulation module for tunnelling different protocols like ↵Martin Varghese
MPLS, IP, NSH etc. The Bareudp tunnel module provides a generic L3 encapsulation tunnelling module for tunnelling different protocols like MPLS, IP,NSH etc inside a UDP tunnel. Signed-off-by: Martin Varghese <martin.varghese@nokia.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-04proc: convert everything to "struct proc_ops"Alexey Dobriyan
The most notable change is DEFINE_SHOW_ATTRIBUTE macro split in seq_file.h. Conversion rule is: llseek => proc_lseek unlocked_ioctl => proc_ioctl xxx => proc_xxx delete ".owner = THIS_MODULE" line [akpm@linux-foundation.org: fix drivers/isdn/capi/kcapi_proc.c] [sfr@canb.auug.org.au: fix kernel/sched/psi.c] Link: http://lkml.kernel.org/r/20200122180545.36222f50@canb.auug.org.au Link: http://lkml.kernel.org/r/20191225172546.GB13378@avx2 Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-01-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
Minor conflict in mlx5 because changes happened to code that has moved meanwhile. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-24rt_cpu_seq_next should increase position indexVasily Averin
if seq_file .next fuction does not change position index, read after some lseek can generate unexpected output. https://bugzilla.kernel.org/show_bug.cgi?id=206283 Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-14ipv4: Add "offload" and "trap" indications to routesIdo Schimmel
When performing L3 offload, routes and nexthops are usually programmed into two different tables in the underlying device. Therefore, the fact that a nexthop resides in hardware does not necessarily mean that all the associated routes also reside in hardware and vice-versa. While the kernel can signal to user space the presence of a nexthop in hardware (via 'RTNH_F_OFFLOAD'), it does not have a corresponding flag for routes. In addition, the fact that a route resides in hardware does not necessarily mean that the traffic is offloaded. For example, unreachable routes (i.e., 'RTN_UNREACHABLE') are programmed to trap packets to the CPU so that the kernel will be able to generate the appropriate ICMP error packet. This patch adds an "offload" and "trap" indications to IPv4 routes, so that users will have better visibility into the offload process. 'struct fib_alias' is extended with two new fields that indicate if the route resides in hardware or not and if it is offloading traffic from the kernel or trapping packets to it. Note that the new fields are added in the 6 bytes hole and therefore the struct still fits in a single cache line [1]. Capable drivers are expected to invoke fib_alias_hw_flags_set() with the route's key in order to set the flags. The indications are dumped to user space via a new flags (i.e., 'RTM_F_OFFLOAD' and 'RTM_F_TRAP') in the 'rtm_flags' field in the ancillary header. v2: * Make use of 'struct fib_rt_info' in fib_alias_hw_flags_set() [1] struct fib_alias { struct hlist_node fa_list; /* 0 16 */ struct fib_info * fa_info; /* 16 8 */ u8 fa_tos; /* 24 1 */ u8 fa_type; /* 25 1 */ u8 fa_state; /* 26 1 */ u8 fa_slen; /* 27 1 */ u32 tb_id; /* 28 4 */ s16 fa_default; /* 32 2 */ u8 offload:1; /* 34: 0 1 */ u8 trap:1; /* 34: 1 1 */ u8 unused:6; /* 34: 2 1 */ /* XXX 5 bytes hole, try to pack */ struct callback_head rcu __attribute__((__aligned__(8))); /* 40 16 */ /* size: 56, cachelines: 1, members: 12 */ /* sum members: 50, holes: 1, sum holes: 5 */ /* sum bitfield members: 8 bits (1 bytes) */ /* forced alignments: 1, forced holes: 1, sum forced holes: 5 */ /* last cacheline: 56 bytes */ } __attribute__((__aligned__(8))); Signed-off-by: Ido Schimmel <idosch@mellanox.com> Reviewed-by: David Ahern <dsahern@gmail.com> Reviewed-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-01-14ipv4: Encapsulate function arguments in a structIdo Schimmel
fib_dump_info() is used to prepare RTM_{NEW,DEL}ROUTE netlink messages using the passed arguments. Currently, the function takes 11 arguments, 6 of which are attributes of the route being dumped (e.g., prefix, TOS). The next patch will need the function to also dump to user space an indication if the route is present in hardware or not. Instead of passing yet another argument, change the function to take a struct containing the different route attributes. v2: * Name last argument of fib_dump_info() * Move 'struct fib_rt_info' to include/net/ip_fib.h so that it could later be passed to fib_alias_hw_flags_set() Signed-off-by: Ido Schimmel <idosch@mellanox.com> Reviewed-by: David Ahern <dsahern@gmail.com> Reviewed-by: Jiri Pirko <jiri@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-12-24net: add bool confirm_neigh parameter for dst_ops.update_pmtuHangbin Liu
The MTU update code is supposed to be invoked in response to real networking events that update the PMTU. In IPv6 PMTU update function __ip6_rt_update_pmtu() we called dst_confirm_neigh() to update neighbor confirmed time. But for tunnel code, it will call pmtu before xmit, like: - tnl_update_pmtu() - skb_dst_update_pmtu() - ip6_rt_update_pmtu() - __ip6_rt_update_pmtu() - dst_confirm_neigh() If the tunnel remote dst mac address changed and we still do the neigh confirm, we will not be able to update neigh cache and ping6 remote will failed. So for this ip_tunnel_xmit() case, _EVEN_ if the MTU is changed, we should not be invoking dst_confirm_neigh() as we have no evidence of successful two-way communication at this point. On the other hand it is also important to keep the neigh reachability fresh for TCP flows, so we cannot remove this dst_confirm_neigh() call. To fix the issue, we have to add a new bool parameter for dst_ops.update_pmtu to choose whether we should do neigh update or not. I will add the parameter in this patch and set all the callers to true to comply with the previous way, and fix the tunnel code one by one on later patches. v5: No change. v4: No change. v3: Do not remove dst_confirm_neigh, but add a new bool parameter in dst_ops.update_pmtu to control whether we should do neighbor confirm. Also split the big patch to small ones for each area. v2: Remove dst_confirm_neigh in __ip6_rt_update_pmtu. Suggested-by: David Miller <davem@davemloft.net> Reviewed-by: Guillaume Nault <gnault@redhat.com> Acked-by: David Ahern <dsahern@gmail.com> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-21ipv4: use dst hint for ipv4 list receivePaolo Abeni
This is alike the previous change, with some additional ipv4 specific quirk. Even when using the route hint we still have to do perform additional per packet checks about source address validity: a new helper is added to wrap them. Hints are explicitly disabled if the destination is a local broadcast, that keeps the code simple and local broadcast are a slower path anyway. UDP flood performances vs recvmmsg() receiver: vanilla patched delta Kpps Kpps % 1683 1871 +11 In the worst case scenario - each packet has a different destination address - the performance delta is within noise range. v3 -> v4: - re-enable hints for forward v2 -> v3: - really fix build (sic) and hint usage check - use fib4_has_custom_rules() helpers (David A.) - add ip_extract_route_hint() helper (Edward C.) - use prev skb as hint instead of copying data (Willem) v1 -> v2: - fix build issue with !CONFIG_IP_MULTIPLE_TABLES Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-05icmp: remove duplicate codeMatteo Croce
The same code which recognizes ICMP error packets is duplicated several times. Use the icmp_is_err() and icmpv6_is_err() helpers instead, which do the same thing. ip_multipath_l3_keys() and tcf_nat_act() didn't check for all the error types, assume that they should instead. Signed-off-by: Matteo Croce <mcroce@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-17ipv4: fix race condition between route lookup and invalidationWei Wang
Jesse and Ido reported the following race condition: <CPU A, t0> - Received packet A is forwarded and cached dst entry is taken from the nexthop ('nhc->nhc_rth_input'). Calls skb_dst_set() <t1> - Given Jesse has busy routers ("ingesting full BGP routing tables from multiple ISPs"), route is added / deleted and rt_cache_flush() is called <CPU B, t2> - Received packet B tries to use the same cached dst entry from t0, but rt_cache_valid() is no longer true and it is replaced in rt_cache_route() by the newer one. This calls dst_dev_put() on the original dst entry which assigns the blackhole netdev to 'dst->dev' <CPU A, t3> - dst_input(skb) is called on packet A and it is dropped due to 'dst->dev' being the blackhole netdev There are 2 issues in the v4 routing code: 1. A per-netns counter is used to do the validation of the route. That means whenever a route is changed in the netns, users of all routes in the netns needs to redo lookup. v6 has an implementation of only updating fn_sernum for routes that are affected. 2. When rt_cache_valid() returns false, rt_cache_route() is called to throw away the current cache, and create a new one. This seems unnecessary because as long as this route does not change, the route cache does not need to be recreated. To fully solve the above 2 issues, it probably needs quite some code changes and requires careful testing, and does not suite for net branch. So this patch only tries to add the deleted cached rt into the uncached list, so user could still be able to use it to receive packets until it's done. Fixes: 95c47f9cf5e0 ("ipv4: call dst_dev_put() properly") Signed-off-by: Wei Wang <weiwan@google.com> Reported-by: Ido Schimmel <idosch@idosch.org> Reported-by: Jesse Hathaway <jesse@mbuki-mvuki.org> Tested-by: Jesse Hathaway <jesse@mbuki-mvuki.org> Acked-by: Martin KaFai Lau <kafai@fb.com> Cc: David Ahern <dsahern@gmail.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-17ipv4: Return -ENETUNREACH if we can't create route but saddr is validStefano Brivio
...instead of -EINVAL. An issue was found with older kernel versions while unplugging a NFS client with pending RPCs, and the wrong error code here prevented it from recovering once link is back up with a configured address. Incidentally, this is not an issue anymore since commit 4f8943f80883 ("SUNRPC: Replace direct task wakeups from softirq context"), included in 5.2-rc7, had the effect of decoupling the forwarding of this error by using SO_ERROR in xs_wake_error(), as pointed out by Benjamin Coddington. To the best of my knowledge, this isn't currently causing any further issue, but the error code doesn't look appropriate anyway, and we might hit this in other paths as well. In detail, as analysed by Gonzalo Siero, once the route is deleted because the interface is down, and can't be resolved and we return -EINVAL here, this ends up, courtesy of inet_sk_rebuild_header(), as the socket error seen by tcp_write_err(), called by tcp_retransmit_timer(). In turn, tcp_write_err() indirectly calls xs_error_report(), which wakes up the RPC pending tasks with a status of -EINVAL. This is then seen by call_status() in the SUN RPC implementation, which aborts the RPC call calling rpc_exit(), instead of handling this as a potentially temporary condition, i.e. as a timeout. Return -EINVAL only if the input parameters passed to ip_route_output_key_hash_rcu() are actually invalid (this is the case if the specified source address is multicast, limited broadcast or all zeroes), but return -ENETUNREACH in all cases where, at the given moment, the given source address doesn't allow resolving the route. While at it, drop the initialisation of err to -ENETUNREACH, which was added to __ip_route_output_key() back then by commit 0315e3827048 ("net: Fix behaviour of unreachable, blackhole and prohibit routes"), but actually had no effect, as it was, and is, overwritten by the fib_lookup() return code assignment, and anyway ignored in all other branches, including the if (fl4->saddr) one: I find this rather confusing, as it would look like -ENETUNREACH is the "default" error, while that statement has no effect. Also note that after commit fc75fc8339e7 ("ipv4: dont create routes on down devices"), we would get -ENETUNREACH if the device is down, but -EINVAL if the source address is specified and we can't resolve the route, and this appears to be rather inconsistent. Reported-by: Stefan Walter <walteste@inf.ethz.ch> Analysed-by: Benjamin Coddington <bcodding@redhat.com> Analysed-by: Gonzalo Siero <gsierohu@redhat.com> Signed-off-by: Stefano Brivio <sbrivio@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>