kernel/linux.git/net/ipv4/fib_semantics.c, branch v6.6.131

net: remove NULL-pointer net parameter in ip_metrics_convert

2024-09-08T05:54:45+00:00

[ Upstream commit 61e2bbafb00e4b9a5de45e6448a7b6b818658576 ] When I was doing some experiments, I found that when using the first parameter, namely, struct net, in ip_metrics_convert() always triggers NULL pointer crash. Then I digged into this part, realizing that we can remove this one due to its uselessness. Signed-off-by: Jason Xing Reviewed-by: Simon Horman Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

ipv4: fix source address selection with route leak

2024-08-03T06:54:13+00:00

commit 6807352353561187a718e87204458999dbcbba1b upstream. By default, an address assigned to the output interface is selected when the source address is not specified. This is problematic when a route, configured in a vrf, uses an interface from another vrf (aka route leak). The original vrf does not own the selected source address. Let's add a check against the output interface and call the appropriate function to select the source address. CC: stable@vger.kernel.org Fixes: 8cbb512c923d ("net: Add source address lookup op for VRF") Signed-off-by: Nicolas Dichtel Reviewed-by: David Ahern Link: https://patch.msgid.link/20240710081521.3809742-2-nicolas.dichtel@6wind.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

ipv4: fib: annotate races around nh->nh_saddr_genid and nh->nh_saddr

2023-10-19T01:11:31+00:00

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 Signed-off-by: Eric Dumazet Reviewed-by: Simon Horman Reviewed-by: David Ahern Link: https://lore.kernel.org/r/20231017192304.82626-1-edumazet@google.com Signed-off-by: Jakub Kicinski

ipv4/fib: send notify when delete source address routes

2023-10-03T07:00:40+00:00

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 Signed-off-by: Hangbin Liu Acked-by: Nicolas Dichtel Reviewed-by: David Ahern Link: https://lore.kernel.org/r/20230922075508.848925-1-liuhangbin@gmail.com Signed-off-by: Paolo Abeni

ipv4: annotate data-races around fi->fib_dead

2023-08-31T09:58:18+00:00

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 Signed-off-by: Eric Dumazet Reviewed-by: David Ahern Link: https://lore.kernel.org/r/20230830095520.1046984-1-edumazet@google.com Signed-off-by: Paolo Abeni

neighbour: switch to standard rcu, instead of rcu_bh

2023-03-22T04:32:18+00:00

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 Signed-off-by: Jakub Kicinski

neighbour: annotate lockless accesses to n->nud_state

2023-03-15T07:37:32+00:00

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 Reviewed-by: David Ahern Reviewed-by: Martin KaFai Lau Signed-off-by: Jakub Kicinski

ipv4: prevent potential spectre v1 gadget in fib_metrics_match()

2023-01-24T05:37:39+00:00

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 Link: https://lore.kernel.org/r/20230120133140.3624204-1-edumazet@google.com Signed-off-by: Jakub Kicinski

ipv4: Fix incorrect route flushing when source address is deleted

2022-12-07T04:34:43+00:00

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 Reviewed-by: David Ahern Signed-off-by: Jakub Kicinski

ipv4: Fix route deletion when nexthop info is not specified

2022-11-29T00:56:04+00:00

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 Tested-by: Jonas Gorski 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 Reviewed-by: Nikolay Aleksandrov Reviewed-by: David Ahern Link: https://lore.kernel.org/r/20221124210932.2470010-1-idosch@nvidia.com Signed-off-by: Jakub Kicinski