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2023-10-18ipv4: fib: annotate races around nh->nh_saddr_genid and nh->nh_saddrEric Dumazet
syzbot reported a data-race while accessing nh->nh_saddr_genid [1] Add annotations, but leave the code lazy as intended. [1] BUG: KCSAN: data-race in fib_select_path / fib_select_path write to 0xffff8881387166f0 of 4 bytes by task 6778 on cpu 1: fib_info_update_nhc_saddr net/ipv4/fib_semantics.c:1334 [inline] fib_result_prefsrc net/ipv4/fib_semantics.c:1354 [inline] fib_select_path+0x292/0x330 net/ipv4/fib_semantics.c:2269 ip_route_output_key_hash_rcu+0x659/0x12c0 net/ipv4/route.c:2810 ip_route_output_key_hash net/ipv4/route.c:2644 [inline] __ip_route_output_key include/net/route.h:134 [inline] ip_route_output_flow+0xa6/0x150 net/ipv4/route.c:2872 send4+0x1f5/0x520 drivers/net/wireguard/socket.c:61 wg_socket_send_skb_to_peer+0x94/0x130 drivers/net/wireguard/socket.c:175 wg_socket_send_buffer_to_peer+0xd6/0x100 drivers/net/wireguard/socket.c:200 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:40 [inline] wg_packet_handshake_send_worker+0x10c/0x150 drivers/net/wireguard/send.c:51 process_one_work kernel/workqueue.c:2630 [inline] process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2703 worker_thread+0x525/0x730 kernel/workqueue.c:2784 kthread+0x1d7/0x210 kernel/kthread.c:388 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 read to 0xffff8881387166f0 of 4 bytes by task 6759 on cpu 0: fib_result_prefsrc net/ipv4/fib_semantics.c:1350 [inline] fib_select_path+0x1cb/0x330 net/ipv4/fib_semantics.c:2269 ip_route_output_key_hash_rcu+0x659/0x12c0 net/ipv4/route.c:2810 ip_route_output_key_hash net/ipv4/route.c:2644 [inline] __ip_route_output_key include/net/route.h:134 [inline] ip_route_output_flow+0xa6/0x150 net/ipv4/route.c:2872 send4+0x1f5/0x520 drivers/net/wireguard/socket.c:61 wg_socket_send_skb_to_peer+0x94/0x130 drivers/net/wireguard/socket.c:175 wg_socket_send_buffer_to_peer+0xd6/0x100 drivers/net/wireguard/socket.c:200 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:40 [inline] wg_packet_handshake_send_worker+0x10c/0x150 drivers/net/wireguard/send.c:51 process_one_work kernel/workqueue.c:2630 [inline] process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2703 worker_thread+0x525/0x730 kernel/workqueue.c:2784 kthread+0x1d7/0x210 kernel/kthread.c:388 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 value changed: 0x959d3217 -> 0x959d3218 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 6759 Comm: kworker/u4:15 Not tainted 6.6.0-rc4-syzkaller-00029-gcbf3a2cb156a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Workqueue: wg-kex-wg1 wg_packet_handshake_send_worker Fixes: 436c3b66ec98 ("ipv4: Invalidate nexthop cache nh_saddr more correctly.") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Simon Horman <horms@kernel.org> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20231017192304.82626-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-10-03ipv4/fib: send notify when delete source address routesHangbin Liu
After deleting an interface address in fib_del_ifaddr(), the function scans the fib_info list for stray entries and calls fib_flush() and fib_table_flush(). Then the stray entries will be deleted silently and no RTM_DELROUTE notification will be sent. This lack of notification can make routing daemons, or monitor like `ip monitor route` miss the routing changes. e.g. + ip link add dummy1 type dummy + ip link add dummy2 type dummy + ip link set dummy1 up + ip link set dummy2 up + ip addr add 192.168.5.5/24 dev dummy1 + ip route add 7.7.7.0/24 dev dummy2 src 192.168.5.5 + ip -4 route 7.7.7.0/24 dev dummy2 scope link src 192.168.5.5 192.168.5.0/24 dev dummy1 proto kernel scope link src 192.168.5.5 + ip monitor route + ip addr del 192.168.5.5/24 dev dummy1 Deleted 192.168.5.0/24 dev dummy1 proto kernel scope link src 192.168.5.5 Deleted broadcast 192.168.5.255 dev dummy1 table local proto kernel scope link src 192.168.5.5 Deleted local 192.168.5.5 dev dummy1 table local proto kernel scope host src 192.168.5.5 As Ido reminded, fib_table_flush() isn't only called when an address is deleted, but also when an interface is deleted or put down. The lack of notification in these cases is deliberate. And commit 7c6bb7d2faaf ("net/ipv6: Add knob to skip DELROUTE message on device down") introduced a sysctl to make IPv6 behave like IPv4 in this regard. So we can't send the route delete notify blindly in fib_table_flush(). To fix this issue, let's add a new flag in "struct fib_info" to track the deleted prefer source address routes, and only send notify for them. After update: + ip monitor route + ip addr del 192.168.5.5/24 dev dummy1 Deleted 192.168.5.0/24 dev dummy1 proto kernel scope link src 192.168.5.5 Deleted broadcast 192.168.5.255 dev dummy1 table local proto kernel scope link src 192.168.5.5 Deleted local 192.168.5.5 dev dummy1 table local proto kernel scope host src 192.168.5.5 Deleted 7.7.7.0/24 dev dummy2 scope link src 192.168.5.5 Suggested-by: Thomas Haller <thaller@redhat.com> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20230922075508.848925-1-liuhangbin@gmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-08-31ipv4: annotate data-races around fi->fib_deadEric Dumazet
syzbot complained about a data-race in fib_table_lookup() [1] Add appropriate annotations to document it. [1] BUG: KCSAN: data-race in fib_release_info / fib_table_lookup write to 0xffff888150f31744 of 1 bytes by task 1189 on cpu 0: fib_release_info+0x3a0/0x460 net/ipv4/fib_semantics.c:281 fib_table_delete+0x8d2/0x900 net/ipv4/fib_trie.c:1777 fib_magic+0x1c1/0x1f0 net/ipv4/fib_frontend.c:1106 fib_del_ifaddr+0x8cf/0xa60 net/ipv4/fib_frontend.c:1317 fib_inetaddr_event+0x77/0x200 net/ipv4/fib_frontend.c:1448 notifier_call_chain kernel/notifier.c:93 [inline] blocking_notifier_call_chain+0x90/0x200 kernel/notifier.c:388 __inet_del_ifa+0x4df/0x800 net/ipv4/devinet.c:432 inet_del_ifa net/ipv4/devinet.c:469 [inline] inetdev_destroy net/ipv4/devinet.c:322 [inline] inetdev_event+0x553/0xaf0 net/ipv4/devinet.c:1606 notifier_call_chain kernel/notifier.c:93 [inline] raw_notifier_call_chain+0x6b/0x1c0 kernel/notifier.c:461 call_netdevice_notifiers_info net/core/dev.c:1962 [inline] call_netdevice_notifiers_mtu+0xd2/0x130 net/core/dev.c:2037 dev_set_mtu_ext+0x30b/0x3e0 net/core/dev.c:8673 do_setlink+0x5be/0x2430 net/core/rtnetlink.c:2837 rtnl_setlink+0x255/0x300 net/core/rtnetlink.c:3177 rtnetlink_rcv_msg+0x807/0x8c0 net/core/rtnetlink.c:6445 netlink_rcv_skb+0x126/0x220 net/netlink/af_netlink.c:2549 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:6463 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x56f/0x640 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x665/0x770 net/netlink/af_netlink.c:1914 sock_sendmsg_nosec net/socket.c:725 [inline] sock_sendmsg net/socket.c:748 [inline] sock_write_iter+0x1aa/0x230 net/socket.c:1129 do_iter_write+0x4b4/0x7b0 fs/read_write.c:860 vfs_writev+0x1a8/0x320 fs/read_write.c:933 do_writev+0xf8/0x220 fs/read_write.c:976 __do_sys_writev fs/read_write.c:1049 [inline] __se_sys_writev fs/read_write.c:1046 [inline] __x64_sys_writev+0x45/0x50 fs/read_write.c:1046 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd read to 0xffff888150f31744 of 1 bytes by task 21839 on cpu 1: fib_table_lookup+0x2bf/0xd50 net/ipv4/fib_trie.c:1585 fib_lookup include/net/ip_fib.h:383 [inline] ip_route_output_key_hash_rcu+0x38c/0x12c0 net/ipv4/route.c:2751 ip_route_output_key_hash net/ipv4/route.c:2641 [inline] __ip_route_output_key include/net/route.h:134 [inline] ip_route_output_flow+0xa6/0x150 net/ipv4/route.c:2869 send4+0x1e7/0x500 drivers/net/wireguard/socket.c:61 wg_socket_send_skb_to_peer+0x94/0x130 drivers/net/wireguard/socket.c:175 wg_socket_send_buffer_to_peer+0xd6/0x100 drivers/net/wireguard/socket.c:200 wg_packet_send_handshake_initiation drivers/net/wireguard/send.c:40 [inline] wg_packet_handshake_send_worker+0x10c/0x150 drivers/net/wireguard/send.c:51 process_one_work+0x434/0x860 kernel/workqueue.c:2600 worker_thread+0x5f2/0xa10 kernel/workqueue.c:2751 kthread+0x1d7/0x210 kernel/kthread.c:389 ret_from_fork+0x2e/0x40 arch/x86/kernel/process.c:145 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 value changed: 0x00 -> 0x01 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 21839 Comm: kworker/u4:18 Tainted: G W 6.5.0-syzkaller #0 Fixes: dccd9ecc3744 ("ipv4: Do not use dead fib_info entries.") Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20230830095520.1046984-1-edumazet@google.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-03-21neighbour: switch to standard rcu, instead of rcu_bhEric Dumazet
rcu_bh is no longer a win, especially for objects freed with standard call_rcu(). Switch neighbour code to no longer disable BH when not necessary. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-03-15neighbour: annotate lockless accesses to n->nud_stateEric Dumazet
We have many lockless accesses to n->nud_state. Before adding another one in the following patch, add annotations to readers and writers. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Reviewed-by: Martin KaFai Lau <martin.lau@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-01-23ipv4: prevent potential spectre v1 gadget in fib_metrics_match()Eric Dumazet
if (!type) continue; if (type > RTAX_MAX) return false; ... fi_val = fi->fib_metrics->metrics[type - 1]; @type being used as an array index, we need to prevent cpu speculation or risk leaking kernel memory content. Fixes: 5f9ae3d9e7e4 ("ipv4: do metrics match when looking up and deleting a route") Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20230120133140.3624204-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-12-06ipv4: Fix incorrect route flushing when source address is deletedIdo Schimmel
Cited commit added the table ID to the FIB info structure, but did not prevent structures with different table IDs from being consolidated. This can lead to routes being flushed from a VRF when an address is deleted from a different VRF. Fix by taking the table ID into account when looking for a matching FIB info. This is already done for FIB info structures backed by a nexthop object in fib_find_info_nh(). Add test cases that fail before the fix: # ./fib_tests.sh -t ipv4_del_addr IPv4 delete address route tests Regular FIB info TEST: Route removed from VRF when source address deleted [ OK ] TEST: Route in default VRF not removed [ OK ] TEST: Route removed in default VRF when source address deleted [ OK ] TEST: Route in VRF is not removed by address delete [ OK ] Identical FIB info with different table ID TEST: Route removed from VRF when source address deleted [FAIL] TEST: Route in default VRF not removed [ OK ] RTNETLINK answers: File exists TEST: Route removed in default VRF when source address deleted [ OK ] TEST: Route in VRF is not removed by address delete [FAIL] Tests passed: 6 Tests failed: 2 And pass after: # ./fib_tests.sh -t ipv4_del_addr IPv4 delete address route tests Regular FIB info TEST: Route removed from VRF when source address deleted [ OK ] TEST: Route in default VRF not removed [ OK ] TEST: Route removed in default VRF when source address deleted [ OK ] TEST: Route in VRF is not removed by address delete [ OK ] Identical FIB info with different table ID TEST: Route removed from VRF when source address deleted [ OK ] TEST: Route in default VRF not removed [ OK ] TEST: Route removed in default VRF when source address deleted [ OK ] TEST: Route in VRF is not removed by address delete [ OK ] Tests passed: 8 Tests failed: 0 Fixes: 5a56a0b3a45d ("net: Don't delete routes in different VRFs") Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-11-28ipv4: Fix route deletion when nexthop info is not specifiedIdo Schimmel
When the kernel receives a route deletion request from user space it tries to delete a route that matches the route attributes specified in the request. If only prefix information is specified in the request, the kernel should delete the first matching FIB alias regardless of its associated FIB info. However, an error is currently returned when the FIB info is backed by a nexthop object: # ip nexthop add id 1 via 192.0.2.2 dev dummy10 # ip route add 198.51.100.0/24 nhid 1 # ip route del 198.51.100.0/24 RTNETLINK answers: No such process Fix by matching on such a FIB info when legacy nexthop attributes are not specified in the request. An earlier check already covers the case where a nexthop ID is specified in the request. Add tests that cover these flows. Before the fix: # ./fib_nexthops.sh -t ipv4_fcnal ... TEST: Delete route when not specifying nexthop attributes [FAIL] Tests passed: 11 Tests failed: 1 After the fix: # ./fib_nexthops.sh -t ipv4_fcnal ... TEST: Delete route when not specifying nexthop attributes [ OK ] Tests passed: 12 Tests failed: 0 No regressions in other tests: # ./fib_nexthops.sh ... Tests passed: 228 Tests failed: 0 # ./fib_tests.sh ... Tests passed: 186 Tests failed: 0 Cc: stable@vger.kernel.org Reported-by: Jonas Gorski <jonas.gorski@gmail.com> Tested-by: Jonas Gorski <jonas.gorski@gmail.com> Fixes: 493ced1ac47c ("ipv4: Allow routes to use nexthop objects") Fixes: 6bf92d70e690 ("net: ipv4: fix route with nexthop object delete warning") Fixes: 61b91eb33a69 ("ipv4: Handle attempt to delete multipath route when fib_info contains an nh reference") Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20221124210932.2470010-1-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-10-27Revert "ip: fix dflt addr selection for connected nexthop"Nicolas Dichtel
This reverts commit 747c14307214b55dbd8250e1ab44cad8305756f1. As explained by Julian, nhc_scope is related to nhc_gw, not to the route. Revert the original patch. The initial problem is fixed differently in the next commit. Link: https://lore.kernel.org/netdev/6c8a44ba-c2d5-cdf-c5c7-5baf97cba38@ssi.bg/ Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Reviewed-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-10-07ipv4: Handle attempt to delete multipath route when fib_info contains an nh ↵David Ahern
reference Gwangun Jung reported a slab-out-of-bounds access in fib_nh_match: fib_nh_match+0xf98/0x1130 linux-6.0-rc7/net/ipv4/fib_semantics.c:961 fib_table_delete+0x5f3/0xa40 linux-6.0-rc7/net/ipv4/fib_trie.c:1753 inet_rtm_delroute+0x2b3/0x380 linux-6.0-rc7/net/ipv4/fib_frontend.c:874 Separate nexthop objects are mutually exclusive with the legacy multipath spec. Fix fib_nh_match to return if the config for the to be deleted route contains a multipath spec while the fib_info is using a nexthop object. Fixes: 493ced1ac47c ("ipv4: Allow routes to use nexthop objects") Fixes: 6bf92d70e690 ("net: ipv4: fix route with nexthop object delete warning") Reported-by: Gwangun Jung <exsociety@gmail.com> Signed-off-by: David Ahern <dsahern@kernel.org> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Tested-by: Ido Schimmel <idosch@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-21Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
No conflicts. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-20ipv4: Fix a data-race around sysctl_fib_multipath_use_neigh.Kuniyuki Iwashima
While reading sysctl_fib_multipath_use_neigh, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: a6db4494d218 ("net: ipv4: Consider failed nexthops in multipath routes") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-14Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
include/net/sock.h 310731e2f161 ("net: Fix data-races around sysctl_mem.") e70f3c701276 ("Revert "net: set SK_MEM_QUANTUM to 4096"") https://lore.kernel.org/all/20220711120211.7c8b7cba@canb.auug.org.au/ net/ipv4/fib_semantics.c 747c14307214 ("ip: fix dflt addr selection for connected nexthop") d62607c3fe45 ("net: rename reference+tracking helpers") net/tls/tls.h include/net/tls.h 3d8c51b25a23 ("net/tls: Check for errors in tls_device_init") 587903142308 ("tls: create an internal header") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-14ip: fix dflt addr selection for connected nexthopNicolas Dichtel
When a nexthop is added, without a gw address, the default scope was set to 'host'. Thus, when a source address is selected, 127.0.0.1 may be chosen but rejected when the route is used. When using a route without a nexthop id, the scope can be configured in the route, thus the problem doesn't exist. To explain more deeply: when a user creates a nexthop, it cannot specify the scope. To create it, the function nh_create_ipv4() calls fib_check_nh() with scope set to 0. fib_check_nh() calls fib_check_nh_nongw() wich was setting scope to 'host'. Then, nh_create_ipv4() calls fib_info_update_nhc_saddr() with scope set to 'host'. The src addr is chosen before the route is inserted. When a 'standard' route (ie without a reference to a nexthop) is added, fib_create_info() calls fib_info_update_nhc_saddr() with the scope set by the user. iproute2 set the scope to 'link' by default. Here is a way to reproduce the problem: ip netns add foo ip -n foo link set lo up ip netns add bar ip -n bar link set lo up sleep 1 ip -n foo link add name eth0 type dummy ip -n foo link set eth0 up ip -n foo address add 192.168.0.1/24 dev eth0 ip -n foo link add name veth0 type veth peer name veth1 netns bar ip -n foo link set veth0 up ip -n bar link set veth1 up ip -n bar address add 192.168.1.1/32 dev veth1 ip -n bar route add default dev veth1 ip -n foo nexthop add id 1 dev veth0 ip -n foo route add 192.168.1.1 nhid 1 Try to get/use the route: > $ ip -n foo route get 192.168.1.1 > RTNETLINK answers: Invalid argument > $ ip netns exec foo ping -c1 192.168.1.1 > ping: connect: Invalid argument Try without nexthop group (iproute2 sets scope to 'link' by dflt): ip -n foo route del 192.168.1.1 ip -n foo route add 192.168.1.1 dev veth0 Try to get/use the route: > $ ip -n foo route get 192.168.1.1 > 192.168.1.1 dev veth0 src 192.168.0.1 uid 0 > cache > $ ip netns exec foo ping -c1 192.168.1.1 > PING 192.168.1.1 (192.168.1.1) 56(84) bytes of data. > 64 bytes from 192.168.1.1: icmp_seq=1 ttl=64 time=0.039 ms > > --- 192.168.1.1 ping statistics --- > 1 packets transmitted, 1 received, 0% packet loss, time 0ms > rtt min/avg/max/mdev = 0.039/0.039/0.039/0.000 ms CC: stable@vger.kernel.org Fixes: 597cfe4fc339 ("nexthop: Add support for IPv4 nexthops") Reported-by: Edwin Brossette <edwin.brossette@6wind.com> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Link: https://lore.kernel.org/r/20220713114853.29406-1-nicolas.dichtel@6wind.com Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-07-13nexthop: Fix data-races around nexthop_compat_mode.Kuniyuki Iwashima
While reading nexthop_compat_mode, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. Fixes: 4f80116d3df3 ("net: ipv4: add sysctl for nexthop api compatibility mode") Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-06-09net: rename reference+tracking helpersJakub Kicinski
Netdev reference helpers have a dev_ prefix for historic reasons. Renaming the old helpers would be too much churn but we can rename the tracking ones which are relatively recent and should be the default for new code. Rename: dev_hold_track() -> netdev_hold() dev_put_track() -> netdev_put() dev_replace_track() -> netdev_ref_replace() Link: https://lore.kernel.org/r/20220608043955.919359-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-04-11ipv4: Use dscp_t in struct fib_rt_infoGuillaume Nault
Use the new dscp_t type to replace the tos field of struct fib_rt_info. This ensures ECN bits are ignored and makes it compatible with the fa_dscp field of struct fib_alias. This also allows sparse to flag potential incorrect uses of DSCP and ECN bits. Signed-off-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-04-01net: ipv4: fix route with nexthop object delete warningNikolay Aleksandrov
FRR folks have hit a kernel warning[1] while deleting routes[2] which is caused by trying to delete a route pointing to a nexthop id without specifying nhid but matching on an interface. That is, a route is found but we hit a warning while matching it. The warning is from fib_info_nh() in include/net/nexthop.h because we run it on a fib_info with nexthop object. The call chain is: inet_rtm_delroute -> fib_table_delete -> fib_nh_match (called with a nexthop fib_info and also with fc_oif set thus calling fib_info_nh on the fib_info and triggering the warning). The fix is to not do any matching in that branch if the fi has a nexthop object because those are managed separately. I.e. we should match when deleting without nh spec and should fail when deleting a nexthop route with old-style nh spec because nexthop objects are managed separately, e.g.: $ ip r show 1.2.3.4/32 1.2.3.4 nhid 12 via 192.168.11.2 dev dummy0 $ ip r del 1.2.3.4/32 $ ip r del 1.2.3.4/32 nhid 12 <both should work> $ ip r del 1.2.3.4/32 dev dummy0 <should fail with ESRCH> [1] [ 523.462226] ------------[ cut here ]------------ [ 523.462230] WARNING: CPU: 14 PID: 22893 at include/net/nexthop.h:468 fib_nh_match+0x210/0x460 [ 523.462236] Modules linked in: dummy rpcsec_gss_krb5 xt_socket nf_socket_ipv4 nf_socket_ipv6 ip6table_raw iptable_raw bpf_preload xt_statistic ip_set ip_vs_sh ip_vs_wrr ip_vs_rr ip_vs xt_mark nf_tables xt_nat veth nf_conntrack_netlink nfnetlink xt_addrtype br_netfilter overlay dm_crypt nfsv3 nfs fscache netfs vhost_net vhost vhost_iotlb tap tun xt_CHECKSUM xt_MASQUERADE xt_conntrack 8021q garp mrp ipt_REJECT nf_reject_ipv4 ip6table_mangle ip6table_nat iptable_mangle iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 iptable_filter bridge stp llc rfcomm snd_seq_dummy snd_hrtimer rpcrdma rdma_cm iw_cm ib_cm ib_core ip6table_filter xt_comment ip6_tables vboxnetadp(OE) vboxnetflt(OE) vboxdrv(OE) qrtr bnep binfmt_misc xfs vfat fat squashfs loop nvidia_drm(POE) nvidia_modeset(POE) nvidia_uvm(POE) nvidia(POE) intel_rapl_msr intel_rapl_common snd_hda_codec_realtek snd_hda_codec_generic ledtrig_audio snd_hda_codec_hdmi btusb btrtl iwlmvm uvcvideo btbcm snd_hda_intel edac_mce_amd [ 523.462274] videobuf2_vmalloc videobuf2_memops btintel snd_intel_dspcfg videobuf2_v4l2 snd_intel_sdw_acpi bluetooth snd_usb_audio snd_hda_codec mac80211 snd_usbmidi_lib joydev snd_hda_core videobuf2_common kvm_amd snd_rawmidi snd_hwdep snd_seq videodev ccp snd_seq_device libarc4 ecdh_generic mc snd_pcm kvm iwlwifi snd_timer drm_kms_helper snd cfg80211 cec soundcore irqbypass rapl wmi_bmof i2c_piix4 rfkill k10temp pcspkr acpi_cpufreq nfsd auth_rpcgss nfs_acl lockd grace sunrpc drm zram ip_tables crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel nvme sp5100_tco r8169 nvme_core wmi ipmi_devintf ipmi_msghandler fuse [ 523.462300] CPU: 14 PID: 22893 Comm: ip Tainted: P OE 5.16.18-200.fc35.x86_64 #1 [ 523.462302] Hardware name: Micro-Star International Co., Ltd. MS-7C37/MPG X570 GAMING EDGE WIFI (MS-7C37), BIOS 1.C0 10/29/2020 [ 523.462303] RIP: 0010:fib_nh_match+0x210/0x460 [ 523.462304] Code: 7c 24 20 48 8b b5 90 00 00 00 e8 bb ee f4 ff 48 8b 7c 24 20 41 89 c4 e8 ee eb f4 ff 45 85 e4 0f 85 2e fe ff ff e9 4c ff ff ff <0f> 0b e9 17 ff ff ff 3c 0a 0f 85 61 fe ff ff 48 8b b5 98 00 00 00 [ 523.462306] RSP: 0018:ffffaa53d4d87928 EFLAGS: 00010286 [ 523.462307] RAX: 0000000000000000 RBX: ffffaa53d4d87a90 RCX: ffffaa53d4d87bb0 [ 523.462308] RDX: ffff9e3d2ee6be80 RSI: ffffaa53d4d87a90 RDI: ffffffff920ed380 [ 523.462309] RBP: ffff9e3d2ee6be80 R08: 0000000000000064 R09: 0000000000000000 [ 523.462310] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000031 [ 523.462310] R13: 0000000000000020 R14: 0000000000000000 R15: ffff9e3d331054e0 [ 523.462311] FS: 00007f245517c1c0(0000) GS:ffff9e492ed80000(0000) knlGS:0000000000000000 [ 523.462313] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 523.462313] CR2: 000055e5dfdd8268 CR3: 00000003ef488000 CR4: 0000000000350ee0 [ 523.462315] Call Trace: [ 523.462316] <TASK> [ 523.462320] fib_table_delete+0x1a9/0x310 [ 523.462323] inet_rtm_delroute+0x93/0x110 [ 523.462325] rtnetlink_rcv_msg+0x133/0x370 [ 523.462327] ? _copy_to_iter+0xb5/0x6f0 [ 523.462330] ? rtnl_calcit.isra.0+0x110/0x110 [ 523.462331] netlink_rcv_skb+0x50/0xf0 [ 523.462334] netlink_unicast+0x211/0x330 [ 523.462336] netlink_sendmsg+0x23f/0x480 [ 523.462338] sock_sendmsg+0x5e/0x60 [ 523.462340] ____sys_sendmsg+0x22c/0x270 [ 523.462341] ? import_iovec+0x17/0x20 [ 523.462343] ? sendmsg_copy_msghdr+0x59/0x90 [ 523.462344] ? __mod_lruvec_page_state+0x85/0x110 [ 523.462348] ___sys_sendmsg+0x81/0xc0 [ 523.462350] ? netlink_seq_start+0x70/0x70 [ 523.462352] ? __dentry_kill+0x13a/0x180 [ 523.462354] ? __fput+0xff/0x250 [ 523.462356] __sys_sendmsg+0x49/0x80 [ 523.462358] do_syscall_64+0x3b/0x90 [ 523.462361] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 523.462364] RIP: 0033:0x7f24552aa337 [ 523.462365] Code: 0e 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10 [ 523.462366] RSP: 002b:00007fff7f05a838 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 523.462368] RAX: ffffffffffffffda RBX: 000000006245bf91 RCX: 00007f24552aa337 [ 523.462368] RDX: 0000000000000000 RSI: 00007fff7f05a8a0 RDI: 0000000000000003 [ 523.462369] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 [ 523.462370] R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000001 [ 523.462370] R13: 00007fff7f05ce08 R14: 0000000000000000 R15: 000055e5dfdd1040 [ 523.462373] </TASK> [ 523.462374] ---[ end trace ba537bc16f6bf4ed ]--- [2] https://github.com/FRRouting/frr/issues/6412 Fixes: 4c7e8084fd46 ("ipv4: Plumb support for nexthop object in a fib_info") Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-03-15net: Add l3mdev index to flow struct and avoid oif reset for port devicesDavid Ahern
The fundamental premise of VRF and l3mdev core code is binding a socket to a device (l3mdev or netdev with an L3 domain) to indicate L3 scope. Legacy code resets flowi_oif to the l3mdev losing any original port device binding. Ben (among others) has demonstrated use cases where the original port device binding is important and needs to be retained. This patch handles that by adding a new entry to the common flow struct that can indicate the l3mdev index for later rule and table matching avoiding the need to reset flowi_oif. In addition to allowing more use cases that require port device binds, this patch brings a few datapath simplications: 1. l3mdev_fib_rule_match is only called when walking fib rules and always after l3mdev_update_flow. That allows an optimization to bail early for non-VRF type uses cases when flowi_l3mdev is not set. Also, only that index needs to be checked for the FIB table id. 2. l3mdev_update_flow can be called with flowi_oif set to a l3mdev (e.g., VRF) device. By resetting flowi_oif only for this case the FLOWI_FLAG_SKIP_NH_OIF flag is not longer needed and can be removed, removing several checks in the datapath. The flowi_iif path can be simplified to only be called if the it is not loopback (loopback can not be assigned to an L3 domain) and the l3mdev index is not already set. 3. Avoid another device lookup in the output path when the fib lookup returns a reject failure. Note: 2 functional tests for local traffic with reject fib rules are updated to reflect the new direct failure at FIB lookup time for ping rather than the failure on packet path. The current code fails like this: HINT: Fails since address on vrf device is out of device scope COMMAND: ip netns exec ns-A ping -c1 -w1 -I eth1 172.16.3.1 ping: Warning: source address might be selected on device other than: eth1 PING 172.16.3.1 (172.16.3.1) from 172.16.3.1 eth1: 56(84) bytes of data. --- 172.16.3.1 ping statistics --- 1 packets transmitted, 0 received, 100% packet loss, time 0ms where the test now directly fails: HINT: Fails since address on vrf device is out of device scope COMMAND: ip netns exec ns-A ping -c1 -w1 -I eth1 172.16.3.1 ping: connect: No route to host Signed-off-by: David Ahern <dsahern@kernel.org> Tested-by: Ben Greear <greearb@candelatech.com> Link: https://lore.kernel.org/r/20220314204551.16369-1-dsahern@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-17Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
No conflicts. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-17ipv4: fix data races in fib_alias_hw_flags_setEric Dumazet
fib_alias_hw_flags_set() can be used by concurrent threads, and is only RCU protected. We need to annotate accesses to following fields of struct fib_alias: offload, trap, offload_failed Because of READ_ONCE()WRITE_ONCE() limitations, make these field u8. BUG: KCSAN: data-race in fib_alias_hw_flags_set / fib_alias_hw_flags_set read to 0xffff888134224a6a of 1 bytes by task 2013 on cpu 1: fib_alias_hw_flags_set+0x28a/0x470 net/ipv4/fib_trie.c:1050 nsim_fib4_rt_hw_flags_set drivers/net/netdevsim/fib.c:350 [inline] nsim_fib4_rt_add drivers/net/netdevsim/fib.c:367 [inline] nsim_fib4_rt_insert drivers/net/netdevsim/fib.c:429 [inline] nsim_fib4_event drivers/net/netdevsim/fib.c:461 [inline] nsim_fib_event drivers/net/netdevsim/fib.c:881 [inline] nsim_fib_event_work+0x1852/0x2cf0 drivers/net/netdevsim/fib.c:1477 process_one_work+0x3f6/0x960 kernel/workqueue.c:2307 process_scheduled_works kernel/workqueue.c:2370 [inline] worker_thread+0x7df/0xa70 kernel/workqueue.c:2456 kthread+0x1bf/0x1e0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 write to 0xffff888134224a6a of 1 bytes by task 4872 on cpu 0: fib_alias_hw_flags_set+0x2d5/0x470 net/ipv4/fib_trie.c:1054 nsim_fib4_rt_hw_flags_set drivers/net/netdevsim/fib.c:350 [inline] nsim_fib4_rt_add drivers/net/netdevsim/fib.c:367 [inline] nsim_fib4_rt_insert drivers/net/netdevsim/fib.c:429 [inline] nsim_fib4_event drivers/net/netdevsim/fib.c:461 [inline] nsim_fib_event drivers/net/netdevsim/fib.c:881 [inline] nsim_fib_event_work+0x1852/0x2cf0 drivers/net/netdevsim/fib.c:1477 process_one_work+0x3f6/0x960 kernel/workqueue.c:2307 process_scheduled_works kernel/workqueue.c:2370 [inline] worker_thread+0x7df/0xa70 kernel/workqueue.c:2456 kthread+0x1bf/0x1e0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 value changed: 0x00 -> 0x02 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 4872 Comm: kworker/0:0 Not tainted 5.17.0-rc3-syzkaller-00188-g1d41d2e82623-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events nsim_fib_event_work Fixes: 90b93f1b31f8 ("ipv4: Add "offload" and "trap" indications to routes") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://lore.kernel.org/r/20220216173217.3792411-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-07ipv4: Use dscp_t in struct fib_aliasGuillaume Nault
Use the new dscp_t type to replace the fa_tos field of fib_alias. This ensures ECN bits are ignored and makes the field compatible with the fc_dscp field of struct fib_config. Converting old *tos variables and fields to dscp_t allows sparse to flag incorrect uses of DSCP and ECN bits. This patch is entirely about type annotation and shouldn't change any existing behaviour. Signed-off-by: Guillaume Nault <gnault@redhat.com> Acked-by: David Ahern <dsahern@kernel.org> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-25ipv4: get rid of fib_info_hash_{alloc|free}Eric Dumazet
Use kvzalloc()/kvfree() instead of hand coded functions. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-19ipv4: add net_hash_mix() dispersion to fib_info_laddrhash keysEric Dumazet
net/ipv4/fib_semantics.c uses a hash table (fib_info_laddrhash) in which fib_sync_down_addr() can locate fib_info based on IPv4 local address. This hash table is resized based on total number of hashed fib_info, but the hash function is only using the local address. For hosts having many active network namespaces, all fib_info for loopback devices (IPv4 address 127.0.0.1) are hashed into a single bucket, making netns dismantles very slow. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-19ipv4: avoid quadratic behavior in netns dismantleEric Dumazet
net/ipv4/fib_semantics.c uses an hash table of 256 slots, keyed by device ifindexes: fib_info_devhash[DEVINDEX_HASHSIZE] Problem is that with network namespaces, devices tend to use the same ifindex. lo device for instance has a fixed ifindex of one, for all network namespaces. This means that hosts with thousands of netns spend a lot of time looking at some hash buckets with thousands of elements, notably at netns dismantle. Simply add a per netns perturbation (net_hash_mix()) to spread elements more uniformely. Also change fib_devindex_hashfn() to use more entropy. Fixes: aa79e66eee5d ("net: Make ifindex generation per-net namespace") Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-16ipv4: update fib_info_cnt under spinlock protectionEric Dumazet
In the past, free_fib_info() was supposed to be called under RTNL protection. This eventually was no longer the case. Instead of enforcing RTNL it seems we simply can move fib_info_cnt changes to occur when fib_info_lock is held. v2: David Laight suggested to update fib_info_cnt only when an entry is added/deleted to/from the hash table, as fib_info_cnt is used to make sure hash table size is optimal. BUG: KCSAN: data-race in fib_create_info / free_fib_info write to 0xffffffff86e243a0 of 4 bytes by task 26429 on cpu 0: fib_create_info+0xe78/0x3440 net/ipv4/fib_semantics.c:1428 fib_table_insert+0x148/0x10c0 net/ipv4/fib_trie.c:1224 fib_magic+0x195/0x1e0 net/ipv4/fib_frontend.c:1087 fib_add_ifaddr+0xd0/0x2e0 net/ipv4/fib_frontend.c:1109 fib_netdev_event+0x178/0x510 net/ipv4/fib_frontend.c:1466 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0x53/0xb0 kernel/notifier.c:391 __dev_notify_flags+0x1d3/0x3b0 dev_change_flags+0xa2/0xc0 net/core/dev.c:8872 do_setlink+0x810/0x2410 net/core/rtnetlink.c:2719 rtnl_group_changelink net/core/rtnetlink.c:3242 [inline] __rtnl_newlink net/core/rtnetlink.c:3396 [inline] rtnl_newlink+0xb10/0x13b0 net/core/rtnetlink.c:3506 rtnetlink_rcv_msg+0x745/0x7e0 net/core/rtnetlink.c:5571 netlink_rcv_skb+0x14e/0x250 net/netlink/af_netlink.c:2496 rtnetlink_rcv+0x18/0x20 net/core/rtnetlink.c:5589 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x5fc/0x6c0 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x726/0x840 net/netlink/af_netlink.c:1921 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg net/socket.c:724 [inline] ____sys_sendmsg+0x39a/0x510 net/socket.c:2409 ___sys_sendmsg net/socket.c:2463 [inline] __sys_sendmsg+0x195/0x230 net/socket.c:2492 __do_sys_sendmsg net/socket.c:2501 [inline] __se_sys_sendmsg net/socket.c:2499 [inline] __x64_sys_sendmsg+0x42/0x50 net/socket.c:2499 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffffffff86e243a0 of 4 bytes by task 31505 on cpu 1: free_fib_info+0x35/0x80 net/ipv4/fib_semantics.c:252 fib_info_put include/net/ip_fib.h:575 [inline] nsim_fib4_rt_destroy drivers/net/netdevsim/fib.c:294 [inline] nsim_fib4_rt_replace drivers/net/netdevsim/fib.c:403 [inline] nsim_fib4_rt_insert drivers/net/netdevsim/fib.c:431 [inline] nsim_fib4_event drivers/net/netdevsim/fib.c:461 [inline] nsim_fib_event drivers/net/netdevsim/fib.c:881 [inline] nsim_fib_event_work+0x15ca/0x2cf0 drivers/net/netdevsim/fib.c:1477 process_one_work+0x3fc/0x980 kernel/workqueue.c:2298 process_scheduled_works kernel/workqueue.c:2361 [inline] worker_thread+0x7df/0xa70 kernel/workqueue.c:2447 kthread+0x2c7/0x2e0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 value changed: 0x00000d2d -> 0x00000d2e Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 31505 Comm: kworker/1:21 Not tainted 5.16.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events nsim_fib_event_work Fixes: 48bb9eb47b27 ("netdevsim: fib: Add dummy implementation for FIB offload") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Cc: David Laight <David.Laight@ACULAB.COM> Cc: Ido Schimmel <idosch@mellanox.com> Cc: Jiri Pirko <jiri@mellanox.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
No conflicts. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-31lwtunnel: Validate RTA_ENCAP_TYPE attribute lengthDavid Ahern
lwtunnel_valid_encap_type_attr is used to validate encap attributes within a multipath route. Add length validation checking to the type. lwtunnel_valid_encap_type_attr is called converting attributes to fib{6,}_config struct which means it is used before fib_get_nhs, ip6_route_multipath_add, and ip6_route_multipath_del - other locations that use rtnh_ok and then nla_get_u16 on RTA_ENCAP_TYPE attribute. Fixes: 9ed59592e3e3 ("lwtunnel: fix autoload of lwt modules") Signed-off-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-31ipv4: Check attribute length for RTA_FLOW in multipath routeDavid Ahern
Make sure RTA_FLOW is at least 4B before using. Fixes: 4e902c57417c ("[IPv4]: FIB configuration using struct fib_config") Signed-off-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-31ipv4: Check attribute length for RTA_GATEWAY in multipath routeDavid Ahern
syzbot reported uninit-value: ============================================================ BUG: KMSAN: uninit-value in fib_get_nhs+0xac4/0x1f80 net/ipv4/fib_semantics.c:708 fib_get_nhs+0xac4/0x1f80 net/ipv4/fib_semantics.c:708 fib_create_info+0x2411/0x4870 net/ipv4/fib_semantics.c:1453 fib_table_insert+0x45c/0x3a10 net/ipv4/fib_trie.c:1224 inet_rtm_newroute+0x289/0x420 net/ipv4/fib_frontend.c:886 Add helper to validate RTA_GATEWAY length before using the attribute. Fixes: 4e902c57417c ("[IPv4]: FIB configuration using struct fib_config") Reported-by: syzbot+d4b9a2851cc3ce998741@syzkaller.appspotmail.com Signed-off-by: David Ahern <dsahern@kernel.org> Cc: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-07inet: add net device refcount tracker to struct fib_nh_commonEric Dumazet
Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-02ipv4: convert fib_num_tclassid_users to atomic_tEric Dumazet
Before commit faa041a40b9f ("ipv4: Create cleanup helper for fib_nh") changes to net->ipv4.fib_num_tclassid_users were protected by RTNL. After the change, this is no longer the case, as free_fib_info_rcu() runs after rcu grace period, without rtnl being held. Fixes: faa041a40b9f ("ipv4: Create cleanup helper for fib_nh") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: David Ahern <dsahern@kernel.org> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-09-24net: ipv4: Fix rtnexthop len when RTA_FLOW is presentXiao Liang
Multipath RTA_FLOW is embedded in nexthop. Dump it in fib_add_nexthop() to get the length of rtnexthop correct. Fixes: b0f60193632e ("ipv4: Refactor nexthop attributes in fib_dump_info") Signed-off-by: Xiao Liang <shaw.leon@gmail.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
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>
2021-08-02ipv4: Fix refcount warning for new fib_infoDavid Ahern
Ioana reported a refcount warning when booting over NFS: [ 5.042532] ------------[ cut here ]------------ [ 5.047184] refcount_t: addition on 0; use-after-free. [ 5.052324] WARNING: CPU: 7 PID: 1 at lib/refcount.c:25 refcount_warn_saturate+0xa4/0x150 ... [ 5.167201] Call trace: [ 5.169635] refcount_warn_saturate+0xa4/0x150 [ 5.174067] fib_create_info+0xc00/0xc90 [ 5.177982] fib_table_insert+0x8c/0x620 [ 5.181893] fib_magic.isra.0+0x110/0x11c [ 5.185891] fib_add_ifaddr+0xb8/0x190 [ 5.189629] fib_inetaddr_event+0x8c/0x140 fib_treeref needs to be set after kzalloc. The old code had a ++ which led to the confusion when the int was replaced by a refcount_t. Fixes: 79976892f7ea ("net: convert fib_treeref from int to refcount_t") Signed-off-by: David Ahern <dsahern@kernel.org> Reported-by: Ioana Ciornei <ciorneiioana@gmail.com> Cc: Yajun Deng <yajun.deng@linux.dev> Tested-by: Matthieu Baerts <matthieu.baerts@tessares.net> Link: https://lore.kernel.org/r/20210802160221.27263-1-dsahern@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-07-30net: convert fib_treeref from int to refcount_tYajun Deng
refcount_t type should be used instead of int when fib_treeref is used as a reference counter,and avoid use-after-free risks. Signed-off-by: Yajun Deng <yajun.deng@linux.dev> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20210729071350.28919-1-yajun.deng@linux.dev Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-05-17ipv4: Fix fall-through warnings for ClangGustavo A. R. Silva
In preparation to enable -Wimplicit-fallthrough for Clang, fix multiple warnings by explicitly adding multiple break statements instead of just letting the code fall through to the next case. Link: https://github.com/KSPP/linux/issues/115 Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
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>
2021-02-02net: ipv4: Publish fib_nlmsg_size()Amit Cohen
Publish fib_nlmsg_size() to allow it to be used later on from fib_alias_hw_flags_set(). Remove the inline keyword since it shouldn't be used inside C files. Signed-off-by: Amit Cohen <amcohen@nvidia.com> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-02-02net: ipv4: Pass fib_rt_info as const to fib_dump_info()Amit Cohen
fib_dump_info() does not change 'fri', so pass it as 'const'. It will later allow us to invoke fib_dump_info() from fib_alias_hw_flags_set(). Signed-off-by: Amit Cohen <amcohen@nvidia.com> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-16treewide: rename nla_strlcpy to nla_strscpy.Francis Laniel
Calls to nla_strlcpy are now replaced by calls to nla_strscpy which is the new name of this function. Signed-off-by: Francis Laniel <laniel_francis@privacyrequired.com> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-11ipv4: Set nexthop flags in a more consistent wayIdo Schimmel
Be more consistent about the way in which the nexthop flags are set and set them in one go. Suggested-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20201110102553.1924232-1-idosch@idosch.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-06rtnetlink: Add RTNH_F_TRAP flagIdo Schimmel
The flag indicates to user space that the nexthop is not programmed to forward packets in hardware, but rather to trap them to the CPU. This is needed, for example, when the MAC of the nexthop neighbour is not resolved and packets should reach the CPU to trigger neighbour resolution. The flag will be used in subsequent patches by netdevsim to test nexthop objects programming to device drivers and in the future by mlxsw as well. Changes since RFC: * Reword commit message Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-06-18net: Fix the arp error in some casesguodeqing
ie., $ ifconfig eth0 6.6.6.6 netmask 255.255.255.0 $ ip rule add from 6.6.6.6 table 6666 $ ip route add 9.9.9.9 via 6.6.6.6 $ ping -I 6.6.6.6 9.9.9.9 PING 9.9.9.9 (9.9.9.9) from 6.6.6.6 : 56(84) bytes of data. 3 packets transmitted, 0 received, 100% packet loss, time 2079ms $ arp Address HWtype HWaddress Flags Mask Iface 6.6.6.6 (incomplete) eth0 The arp request address is error, this is because fib_table_lookup in fib_check_nh lookup the destnation 9.9.9.9 nexthop, the scope of the fib result is RT_SCOPE_LINK,the correct scope is RT_SCOPE_HOST. Here I add a check of whether this is RT_TABLE_MAIN to solve this problem. Fixes: 3bfd847203c6 ("net: Use passed in table for nexthop lookups") Signed-off-by: guodeqing <geffrey.guo@huawei.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-28net: ipv4: add sysctl for nexthop api compatibility modeRoopa Prabhu
Current route nexthop API maintains user space compatibility with old route API by default. Dumps and netlink notifications support both new and old API format. In systems which have moved to the new API, this compatibility mode cancels some of the performance benefits provided by the new nexthop API. This patch adds new sysctl nexthop_compat_mode which is on by default but provides the ability to turn off compatibility mode allowing systems to run entirely with the new routing API. Old route API behaviour and support is not modified by this sysctl. Uses a single sysctl to cover both ipv4 and ipv6 following other sysctls. Covers dumps and delete notifications as suggested by David Ahern. Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-04-22ipv4: Update fib_select_default to handle nexthop objectsDavid Ahern
A user reported [0] hitting the WARN_ON in fib_info_nh: [ 8633.839816] ------------[ cut here ]------------ [ 8633.839819] WARNING: CPU: 0 PID: 1719 at include/net/nexthop.h:251 fib_select_path+0x303/0x381 ... [ 8633.839846] RIP: 0010:fib_select_path+0x303/0x381 ... [ 8633.839848] RSP: 0018:ffffb04d407f7d00 EFLAGS: 00010286 [ 8633.839850] RAX: 0000000000000000 RBX: ffff9460b9897ee8 RCX: 00000000000000fe [ 8633.839851] RDX: 0000000000000000 RSI: 00000000ffffffff RDI: 0000000000000000 [ 8633.839852] RBP: ffff946076049850 R08: 0000000059263a83 R09: ffff9460840e4000 [ 8633.839853] R10: 0000000000000014 R11: 0000000000000000 R12: ffffb04d407f7dc0 [ 8633.839854] R13: ffffffffa4ce3240 R14: 0000000000000000 R15: ffff9460b7681f60 [ 8633.839857] FS: 00007fcac2e02700(0000) GS:ffff9460bdc00000(0000) knlGS:0000000000000000 [ 8633.839858] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 8633.839859] CR2: 00007f27beb77e28 CR3: 0000000077734000 CR4: 00000000000006f0 [ 8633.839867] Call Trace: [ 8633.839871] ip_route_output_key_hash_rcu+0x421/0x890 [ 8633.839873] ip_route_output_key_hash+0x5e/0x80 [ 8633.839876] ip_route_output_flow+0x1a/0x50 [ 8633.839878] __ip4_datagram_connect+0x154/0x310 [ 8633.839880] ip4_datagram_connect+0x28/0x40 [ 8633.839882] __sys_connect+0xd6/0x100 ... The WARN_ON is triggered in fib_select_default which is invoked when there are multiple default routes. Update the function to use fib_info_nhc and convert the nexthop checks to use fib_nh_common. Add test case that covers the affected code path. [0] https://github.com/FRRouting/frr/issues/6089 Fixes: 493ced1ac47c ("ipv4: Allow routes to use nexthop objects") Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-29net: add net available in build_stateAlexander Aring
The build_state callback of lwtunnel doesn't contain the net namespace structure yet. This patch will add it so we can check on specific address configuration at creation time of rpl source routes. Signed-off-by: Alexander Aring <alex.aring@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-12inet: Use fallthrough;Joe Perches
Convert the various uses of fallthrough comments to fallthrough; Done via script Link: https://lore.kernel.org/lkml/b56602fcf79f849e733e7b521bb0e17895d390fa.1582230379.git.joe@perches.com/ And by hand: net/ipv6/ip6_fib.c has a fallthrough comment outside of an #ifdef block that causes gcc to emit a warning if converted in-place. So move the new fallthrough; inside the containing #ifdef/#endif too. Signed-off-by: Joe Perches <joe@perches.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>