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2022-11-03nh: fix scope used to find saddr when adding non gw nhNicolas Dichtel
[ Upstream commit bac0f937c343d651874f83b265ca8f5070ed4f06 ] As explained by Julian, fib_nh_scope is related to fib_nh_gw4, but fib_info_update_nhc_saddr() needs the scope of the route, which is the scope "before" fib_nh_scope, ie fib_nh_scope - 1. This patch fixes the problem described in commit 747c14307214 ("ip: fix dflt addr selection for connected nexthop"). Fixes: 597cfe4fc339 ("nexthop: Add support for IPv4 nexthops") 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> Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-07-21nexthop: Fix data-races around nexthop_compat_mode.Kuniyuki Iwashima
[ Upstream commit bdf00bf24bef9be1ca641a6390fd5487873e0d2e ] 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> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-12-01net: nexthop: release IPv6 per-cpu dsts when replacing a nexthop groupNikolay Aleksandrov
[ Upstream commit 1005f19b9357b81aa64e1decd08d6e332caaa284 ] When replacing a nexthop group, we must release the IPv6 per-cpu dsts of the removed nexthop entries after an RCU grace period because they contain references to the nexthop's net device and to the fib6 info. With specific series of events[1] we can reach net device refcount imbalance which is unrecoverable. IPv4 is not affected because dsts don't take a refcount on the route. [1] $ ip nexthop list id 200 via 2002:db8::2 dev bridge.10 scope link onlink id 201 via 2002:db8::3 dev bridge scope link onlink id 203 group 201/200 $ ip -6 route 2001:db8::10 nhid 203 metric 1024 pref medium nexthop via 2002:db8::3 dev bridge weight 1 onlink nexthop via 2002:db8::2 dev bridge.10 weight 1 onlink Create rt6_info through one of the multipath legs, e.g.: $ taskset -a -c 1 ./pkt_inj 24 bridge.10 2001:db8::10 (pkt_inj is just a custom packet generator, nothing special) Then remove that leg from the group by replace (let's assume it is id 200 in this case): $ ip nexthop replace id 203 group 201 Now remove the IPv6 route: $ ip -6 route del 2001:db8::10/128 The route won't be really deleted due to the stale rt6_info holding 1 refcnt in nexthop id 200. At this point we have the following reference count dependency: (deleted) IPv6 route holds 1 reference over nhid 203 nh 203 holds 1 ref over id 201 nh 200 holds 1 ref over the net device and the route due to the stale rt6_info Now to create circular dependency between nh 200 and the IPv6 route, and also to get a reference over nh 200, restore nhid 200 in the group: $ ip nexthop replace id 203 group 201/200 And now we have a permanent circular dependncy because nhid 203 holds a reference over nh 200 and 201, but the route holds a ref over nh 203 and is deleted. To trigger the bug just delete the group (nhid 203): $ ip nexthop del id 203 It won't really be deleted due to the IPv6 route dependency, and now we have 2 unlinked and deleted objects that reference each other: the group and the IPv6 route. Since the group drops the reference it holds over its entries at free time (i.e. its own refcount needs to drop to 0) that will never happen and we get a permanent ref on them, since one of the entries holds a reference over the IPv6 route it will also never be released. At this point the dependencies are: (deleted, only unlinked) IPv6 route holds reference over group nh 203 (deleted, only unlinked) group nh 203 holds reference over nh 201 and 200 nh 200 holds 1 ref over the net device and the route due to the stale rt6_info This is the last point where it can be fixed by running traffic through nh 200, and specifically through the same CPU so the rt6_info (dst) will get released due to the IPv6 genid, that in turn will free the IPv6 route, which in turn will free the ref count over the group nh 203. If nh 200 is deleted at this point, it will never be released due to the ref from the unlinked group 203, it will only be unlinked: $ ip nexthop del id 200 $ ip nexthop $ Now we can never release that stale rt6_info, we have IPv6 route with ref over group nh 203, group nh 203 with ref over nh 200 and 201, nh 200 with rt6_info (dst) with ref over the net device and the IPv6 route. All of these objects are only unlinked, and cannot be released, thus they can't release their ref counts. Message from syslogd@dev at Nov 19 14:04:10 ... kernel:[73501.828730] unregister_netdevice: waiting for bridge.10 to become free. Usage count = 3 Message from syslogd@dev at Nov 19 14:04:20 ... kernel:[73512.068811] unregister_netdevice: waiting for bridge.10 to become free. Usage count = 3 Fixes: 7bf4796dd099 ("nexthops: add support for replace") Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-12-01net: nexthop: fix null pointer dereference when IPv6 is not enabledNikolay Aleksandrov
commit 1c743127cc54b112b155f434756bd4b5fa565a99 upstream. When we try to add an IPv6 nexthop and IPv6 is not enabled (!CONFIG_IPV6) we'll hit a NULL pointer dereference[1] in the error path of nh_create_ipv6() due to calling ipv6_stub->fib6_nh_release. The bug has been present since the beginning of IPv6 nexthop gateway support. Commit 1aefd3de7bc6 ("ipv6: Add fib6_nh_init and release to stubs") tells us that only fib6_nh_init has a dummy stub because fib6_nh_release should not be called if fib6_nh_init returns an error, but the commit below added a call to ipv6_stub->fib6_nh_release in its error path. To fix it return the dummy stub's -EAFNOSUPPORT error directly without calling ipv6_stub->fib6_nh_release in nh_create_ipv6()'s error path. [1] Output is a bit truncated, but it clearly shows the error. BUG: kernel NULL pointer dereference, address: 000000000000000000 #PF: supervisor instruction fetch in kernel modede #PF: error_code(0x0010) - not-present pagege PGD 0 P4D 0 Oops: 0010 [#1] PREEMPT SMP NOPTI CPU: 4 PID: 638 Comm: ip Kdump: loaded Not tainted 5.16.0-rc1+ #446 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-4.fc34 04/01/2014 RIP: 0010:0x0 Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6. RSP: 0018:ffff888109f5b8f0 EFLAGS: 00010286^Ac RAX: 0000000000000000 RBX: ffff888109f5ba28 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8881008a2860 RBP: ffff888109f5b9d8 R08: 0000000000000000 R09: 0000000000000000 R10: ffff888109f5b978 R11: ffff888109f5b948 R12: 00000000ffffff9f R13: ffff8881008a2a80 R14: ffff8881008a2860 R15: ffff8881008a2840 FS: 00007f98de70f100(0000) GS:ffff88822bf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffffffffd6 CR3: 0000000100efc000 CR4: 00000000000006e0 Call Trace: <TASK> nh_create_ipv6+0xed/0x10c rtm_new_nexthop+0x6d7/0x13f3 ? check_preemption_disabled+0x3d/0xf2 ? lock_is_held_type+0xbe/0xfd rtnetlink_rcv_msg+0x23f/0x26a ? check_preemption_disabled+0x3d/0xf2 ? rtnl_calcit.isra.0+0x147/0x147 netlink_rcv_skb+0x61/0xb2 netlink_unicast+0x100/0x187 netlink_sendmsg+0x37f/0x3a0 ? netlink_unicast+0x187/0x187 sock_sendmsg_nosec+0x67/0x9b ____sys_sendmsg+0x19d/0x1f9 ? copy_msghdr_from_user+0x4c/0x5e ? rcu_read_lock_any_held+0x2a/0x78 ___sys_sendmsg+0x6c/0x8c ? asm_sysvec_apic_timer_interrupt+0x12/0x20 ? lockdep_hardirqs_on+0xd9/0x102 ? sockfd_lookup_light+0x69/0x99 __sys_sendmsg+0x50/0x6e do_syscall_64+0xcb/0xf2 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f98dea28914 Code: 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b5 0f 1f 80 00 00 00 00 48 8d 05 e9 5d 0c 00 8b 00 85 c0 75 13 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 41 54 41 89 d4 55 48 89 f5 53 RSP: 002b:00007fff859f5e68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e2e RAX: ffffffffffffffda RBX: 00000000619cb810 RCX: 00007f98dea28914 RDX: 0000000000000000 RSI: 00007fff859f5ed0 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000008 R10: fffffffffffffce6 R11: 0000000000000246 R12: 0000000000000001 R13: 000055c0097ae520 R14: 000055c0097957fd R15: 00007fff859f63a0 </TASK> Modules linked in: bridge stp llc bonding virtio_net Cc: stable@vger.kernel.org Fixes: 53010f991a9f ("nexthop: Add support for IPv6 gateways") Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-09-22Set fc_nlinfo in nh_create_ipv4, nh_create_ipv6Ryoga Saito
[ Upstream commit 9aca491e0dccf8a9d84a5b478e5eee3c6ea7803b ] This patch fixes kernel NULL pointer dereference when creating nexthop which is bound with SRv6 decapsulation. In the creation of nexthop, __seg6_end_dt_vrf_build is called. __seg6_end_dt_vrf_build expects fc_lninfo in fib6_config is set correctly, but it isn't set in nh_create_ipv6, which causes kernel crash. Here is steps to reproduce kernel crash: 1. modprobe vrf 2. ip -6 nexthop add encap seg6local action End.DT4 vrftable 1 dev eth0 We got the following message: [ 901.370336] BUG: kernel NULL pointer dereference, address: 0000000000000ba0 [ 901.371658] #PF: supervisor read access in kernel mode [ 901.372672] #PF: error_code(0x0000) - not-present page [ 901.373672] PGD 0 P4D 0 [ 901.374248] Oops: 0000 [#1] SMP PTI [ 901.374944] CPU: 0 PID: 8593 Comm: ip Not tainted 5.14-051400-generic #202108310811-Ubuntu [ 901.376404] Hardware name: Red Hat KVM, BIOS 1.11.1-4.module_el8.2.0+320+13f867d7 04/01/2014 [ 901.377907] RIP: 0010:vrf_ifindex_lookup_by_table_id+0x19/0x90 [vrf] [ 901.379182] Code: c1 e9 72 ff ff ff e8 96 49 01 c2 66 0f 1f 44 00 00 0f 1f 44 00 00 55 48 89 e5 41 56 41 55 41 89 f5 41 54 53 8b 05 47 4c 00 00 <48> 8b 97 a0 0b 00 00 48 8b 1c c2 e8 57 27 53 c1 4c 8d a3 88 00 00 [ 901.382652] RSP: 0018:ffffbf2d02043590 EFLAGS: 00010282 [ 901.383746] RAX: 000000000000000b RBX: ffff990808255e70 RCX: ffffbf2d02043aa8 [ 901.385436] RDX: 0000000000000001 RSI: 0000000000000001 RDI: 0000000000000000 [ 901.386924] RBP: ffffbf2d020435b0 R08: 00000000000000c0 R09: ffff990808255e40 [ 901.388537] R10: ffffffff83b08c90 R11: 0000000000000009 R12: 0000000000000000 [ 901.389937] R13: 0000000000000001 R14: 0000000000000000 R15: 000000000000000b [ 901.391226] FS: 00007fe49381f740(0000) GS:ffff99087dc00000(0000) knlGS:0000000000000000 [ 901.392737] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 901.393803] CR2: 0000000000000ba0 CR3: 000000000e3e8003 CR4: 0000000000770ef0 [ 901.395122] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 901.396496] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 901.397833] PKRU: 55555554 [ 901.398578] Call Trace: [ 901.399144] l3mdev_ifindex_lookup_by_table_id+0x3b/0x70 [ 901.400179] __seg6_end_dt_vrf_build+0x34/0xd0 [ 901.401067] seg6_end_dt4_build+0x16/0x20 [ 901.401904] seg6_local_build_state+0x271/0x430 [ 901.402797] lwtunnel_build_state+0x81/0x130 [ 901.403645] fib_nh_common_init+0x82/0x100 [ 901.404465] ? sock_def_readable+0x4b/0x80 [ 901.405285] fib6_nh_init+0x115/0x7c0 [ 901.406033] nh_create_ipv6.isra.0+0xe1/0x140 [ 901.406932] rtm_new_nexthop+0x3b7/0xeb0 [ 901.407828] rtnetlink_rcv_msg+0x152/0x3a0 [ 901.408663] ? rtnl_calcit.isra.0+0x130/0x130 [ 901.409535] netlink_rcv_skb+0x55/0x100 [ 901.410319] rtnetlink_rcv+0x15/0x20 [ 901.411026] netlink_unicast+0x1a8/0x250 [ 901.411813] netlink_sendmsg+0x238/0x470 [ 901.412602] ? _copy_from_user+0x2b/0x60 [ 901.413394] sock_sendmsg+0x65/0x70 [ 901.414112] ____sys_sendmsg+0x218/0x290 [ 901.414929] ? copy_msghdr_from_user+0x5c/0x90 [ 901.415814] ___sys_sendmsg+0x81/0xc0 [ 901.416559] ? fsnotify_destroy_marks+0x27/0xf0 [ 901.417447] ? call_rcu+0xa4/0x230 [ 901.418153] ? kmem_cache_free+0x23f/0x410 [ 901.418972] ? dentry_free+0x37/0x70 [ 901.419705] ? mntput_no_expire+0x4c/0x260 [ 901.420574] __sys_sendmsg+0x62/0xb0 [ 901.421297] __x64_sys_sendmsg+0x1f/0x30 [ 901.422057] do_syscall_64+0x5c/0xc0 [ 901.422756] ? syscall_exit_to_user_mode+0x27/0x50 [ 901.423675] ? __x64_sys_close+0x12/0x40 [ 901.424462] ? do_syscall_64+0x69/0xc0 [ 901.425219] ? irqentry_exit_to_user_mode+0x9/0x20 [ 901.426149] ? irqentry_exit+0x19/0x30 [ 901.426901] ? exc_page_fault+0x89/0x160 [ 901.427709] ? asm_exc_page_fault+0x8/0x30 [ 901.428536] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 901.429514] RIP: 0033:0x7fe493945747 [ 901.430248] Code: 64 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 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 [ 901.433549] RSP: 002b:00007ffe9932cf68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 901.434981] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fe493945747 [ 901.436303] RDX: 0000000000000000 RSI: 00007ffe9932cfe0 RDI: 0000000000000003 [ 901.437607] RBP: 00000000613053f7 R08: 0000000000000001 R09: 00007ffe9932d07c [ 901.438990] R10: 000055f4a903a010 R11: 0000000000000246 R12: 0000000000000001 [ 901.440340] R13: 0000000000000001 R14: 000055f4a802b163 R15: 000055f4a8042020 [ 901.441630] Modules linked in: vrf nls_utf8 isofs nls_iso8859_1 dm_multipath scsi_dh_rdac scsi_dh_emc scsi_dh_alua intel_rapl_msr intel_rapl_common isst_if_mbox_msr isst_if_common nfit rapl input_leds joydev serio_raw qemu_fw_cfg mac_hid sch_fq_codel drm virtio_rng ip_tables x_tables autofs4 btrfs blake2b_generic zstd_compress raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c raid1 raid0 multipath linear crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel crypto_simd virtio_net net_failover cryptd psmouse virtio_blk failover i2c_piix4 pata_acpi floppy [ 901.450808] CR2: 0000000000000ba0 [ 901.451514] ---[ end trace c27b934b99ade304 ]--- [ 901.452403] RIP: 0010:vrf_ifindex_lookup_by_table_id+0x19/0x90 [vrf] [ 901.453626] Code: c1 e9 72 ff ff ff e8 96 49 01 c2 66 0f 1f 44 00 00 0f 1f 44 00 00 55 48 89 e5 41 56 41 55 41 89 f5 41 54 53 8b 05 47 4c 00 00 <48> 8b 97 a0 0b 00 00 48 8b 1c c2 e8 57 27 53 c1 4c 8d a3 88 00 00 [ 901.456910] RSP: 0018:ffffbf2d02043590 EFLAGS: 00010282 [ 901.457912] RAX: 000000000000000b RBX: ffff990808255e70 RCX: ffffbf2d02043aa8 [ 901.459238] RDX: 0000000000000001 RSI: 0000000000000001 RDI: 0000000000000000 [ 901.460552] RBP: ffffbf2d020435b0 R08: 00000000000000c0 R09: ffff990808255e40 [ 901.461882] R10: ffffffff83b08c90 R11: 0000000000000009 R12: 0000000000000000 [ 901.463208] R13: 0000000000000001 R14: 0000000000000000 R15: 000000000000000b [ 901.464529] FS: 00007fe49381f740(0000) GS:ffff99087dc00000(0000) knlGS:0000000000000000 [ 901.466058] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 901.467189] CR2: 0000000000000ba0 CR3: 000000000e3e8003 CR4: 0000000000770ef0 [ 901.468515] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 901.469858] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 901.471139] PKRU: 55555554 Signed-off-by: Ryoga Saito <contact@proelbtn.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-03-17nexthop: Do not flush blackhole nexthops when loopback goes downIdo Schimmel
commit 76c03bf8e2624076b88d93542d78e22d5345c88e upstream. As far as user space is concerned, blackhole nexthops do not have a nexthop device and therefore should not be affected by the administrative or carrier state of any netdev. However, when the loopback netdev goes down all the blackhole nexthops are flushed. This happens because internally the kernel associates blackhole nexthops with the loopback netdev. This behavior is both confusing to those not familiar with kernel internals and also diverges from the legacy API where blackhole IPv4 routes are not flushed when the loopback netdev goes down: # ip route add blackhole 198.51.100.0/24 # ip link set dev lo down # ip route show 198.51.100.0/24 blackhole 198.51.100.0/24 Blackhole IPv6 routes are flushed, but at least user space knows that they are associated with the loopback netdev: # ip -6 route show 2001:db8:1::/64 blackhole 2001:db8:1::/64 dev lo metric 1024 pref medium Fix this by only flushing blackhole nexthops when the loopback netdev is unregistered. Fixes: ab84be7e54fc ("net: Initial nexthop code") Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reported-by: Donald Sharp <sharpd@nvidia.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-17nexthop: Bounce NHA_GATEWAY in FDB nexthop groupsPetr Machata
[ Upstream commit b19218b27f3477316d296e8bcf4446aaf017aa69 ] The function nh_check_attr_group() is called to validate nexthop groups. The intention of that code seems to have been to bounce all attributes above NHA_GROUP_TYPE except for NHA_FDB. However instead it bounces all these attributes except when NHA_FDB attribute is present--then it accepts them. NHA_FDB validation that takes place before, in rtm_to_nh_config(), already bounces NHA_OIF, NHA_BLACKHOLE, NHA_ENCAP and NHA_ENCAP_TYPE. Yet further back, NHA_GROUPS and NHA_MASTER are bounced unconditionally. But that still leaves NHA_GATEWAY as an attribute that would be accepted in FDB nexthop groups (with no meaning), so long as it keeps the address family as unspecified: # ip nexthop add id 1 fdb via 127.0.0.1 # ip nexthop add id 10 fdb via default group 1 The nexthop code is still relatively new and likely not used very broadly, and the FDB bits are newer still. Even though there is a reproducer out there, it relies on an improbable gateway arguments "via default", "via all" or "via any". Given all this, I believe it is OK to reformulate the condition to do the right thing and bounce NHA_GATEWAY. Fixes: 38428d68719c ("nexthop: support for fdb ecmp nexthops") Signed-off-by: Petr Machata <petrm@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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-17nexthop: Unlink nexthop group entry in error pathIdo Schimmel
[ Upstream commit 7b01e53eee6dce7a8a6736e06b99b68cd0cc7a27 ] In case of error, remove the nexthop group entry from the list to which it was previously added. Fixes: 430a049190de ("nexthop: Add support for nexthop groups") Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Petr Machata <petrm@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-01-17nexthop: Fix off-by-one error in error pathIdo Schimmel
[ Upstream commit 07e61a979ca4dddb3661f59328b3cd109f6b0070 ] A reference was not taken for the current nexthop entry, so do not try to put it in the error path. Fixes: 430a049190de ("nexthop: Add support for nexthop groups") Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Petr Machata <petrm@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-10-19nexthop: Fix performance regression in nexthop deletionIdo Schimmel
While insertion of 16k nexthops all using the same netdev ('dummy10') takes less than a second, deletion takes about 130 seconds: # time -p ip -b nexthop.batch real 0.29 user 0.01 sys 0.15 # time -p ip link set dev dummy10 down real 131.03 user 0.06 sys 0.52 This is because of repeated calls to synchronize_rcu() whenever a nexthop is removed from a nexthop group: # /usr/share/bcc/tools/offcputime -p `pgrep -nx ip` -K ... b'finish_task_switch' b'schedule' b'schedule_timeout' b'wait_for_completion' b'__wait_rcu_gp' b'synchronize_rcu.part.0' b'synchronize_rcu' b'__remove_nexthop' b'remove_nexthop' b'nexthop_flush_dev' b'nh_netdev_event' b'raw_notifier_call_chain' b'call_netdevice_notifiers_info' b'__dev_notify_flags' b'dev_change_flags' b'do_setlink' b'__rtnl_newlink' b'rtnl_newlink' b'rtnetlink_rcv_msg' b'netlink_rcv_skb' b'rtnetlink_rcv' b'netlink_unicast' b'netlink_sendmsg' b'____sys_sendmsg' b'___sys_sendmsg' b'__sys_sendmsg' b'__x64_sys_sendmsg' b'do_syscall_64' b'entry_SYSCALL_64_after_hwframe' - ip (277) 126554955 Since nexthops are always deleted under RTNL, synchronize_net() can be used instead. It will call synchronize_rcu_expedited() which only blocks for several microseconds as opposed to multiple milliseconds like synchronize_rcu(). With this patch deletion of 16k nexthops takes less than a second: # time -p ip link set dev dummy10 down real 0.12 user 0.00 sys 0.04 Tested with fib_nexthops.sh which includes torture tests that prompted the initial change: # ./fib_nexthops.sh ... Tests passed: 134 Tests failed: 0 Fixes: 90f33bffa382 ("nexthops: don't modify published nexthop groups") Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com> Reviewed-by: David Ahern <dsahern@gmail.com> Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com> Link: https://lore.kernel.org/r/20201016172914.643282-1-idosch@idosch.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-09-15nexthop: Only emit a notification when nexthop is actually deletedIdo Schimmel
Currently, the in-kernel delete notification is emitted from the error path of nexthop_add() and replace_nexthop(), which can be confusing to in-kernel listeners as they are not familiar with the nexthop. Instead, only emit the notification when the nexthop is actually deleted. The following sub-cases are covered: 1. User space deletes the nexthop 2. The nexthop is deleted by the kernel due to a netdev event (e.g., nexthop device going down) 3. A group is deleted because its last nexthop is being deleted 4. The network namespace of the nexthop device is deleted Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-09-15nexthop: Convert to blocking notification chainIdo Schimmel
Currently, the only listener of the nexthop notification chain is the VXLAN driver. Subsequent patches will add more listeners (e.g., device drivers such as netdevsim) that need to be able to block when processing notifications. Therefore, convert the notification chain to a blocking one. This is safe as notifications are always emitted from process context. Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-26ipv4: nexthop: Correctly update nexthop group when replacing a nexthopIdo Schimmel
Each nexthop group contains an indication if it has IPv4 nexthops ('has_v4'). Its purpose is to prevent IPv6 routes from using groups with IPv4 nexthops. However, the indication is not updated when a nexthop is replaced. This results in the kernel wrongly rejecting IPv6 routes from pointing to groups that only contain IPv6 nexthops. Example: # ip nexthop replace id 1 via 192.0.2.2 dev dummy10 # ip nexthop replace id 10 group 1 # ip nexthop replace id 1 via 2001:db8:1::2 dev dummy10 # ip route replace 2001:db8:10::/64 nhid 10 Error: IPv6 routes can not use an IPv4 nexthop. Solve this by iterating over all the nexthop groups that the replaced nexthop is a member of and potentially update their IPv4 indication according to the new set of member nexthops. Avoid wasting cycles by only performing the update in case an IPv4 nexthop is replaced by an IPv6 nexthop. Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-26ipv4: nexthop: Correctly update nexthop group when removing a nexthopIdo Schimmel
Each nexthop group contains an indication if it has IPv4 nexthops ('has_v4'). Its purpose is to prevent IPv6 routes from using groups with IPv4 nexthops. However, the indication is not updated when a nexthop is removed. This results in the kernel wrongly rejecting IPv6 routes from pointing to groups that only contain IPv6 nexthops. Example: # ip nexthop replace id 1 via 192.0.2.2 dev dummy10 # ip nexthop replace id 2 via 2001:db8:1::2 dev dummy10 # ip nexthop replace id 10 group 1/2 # ip nexthop del id 1 # ip route replace 2001:db8:10::/64 nhid 10 Error: IPv6 routes can not use an IPv4 nexthop. Solve this by updating the indication according to the new set of member nexthops. Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-26ipv4: nexthop: Remove unnecessary rtnl_dereference()Ido Schimmel
The pointer is not RCU protected, so remove the unnecessary rtnl_dereference(). This suppresses the following warning: net/ipv4/nexthop.c:1101:24: error: incompatible types in comparison expression (different address spaces): net/ipv4/nexthop.c:1101:24: struct rb_node [noderef] __rcu * net/ipv4/nexthop.c:1101:24: struct rb_node * Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-26ipv4: nexthop: Use nla_put_be32() for NHA_GATEWAYIdo Schimmel
The code correctly uses nla_get_be32() to get the payload of the attribute, but incorrectly uses nla_put_u32() to add the attribute to the payload. This results in the following warning: net/ipv4/nexthop.c:279:59: warning: incorrect type in argument 3 (different base types) net/ipv4/nexthop.c:279:59: expected unsigned int [usertype] value net/ipv4/nexthop.c:279:59: got restricted __be32 [usertype] ipv4 Suppress the warning by using nla_put_be32(). Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-26ipv4: nexthop: Reduce allocation size of 'struct nh_group'Ido Schimmel
The struct looks as follows: struct nh_group { struct nh_group *spare; /* spare group for removals */ u16 num_nh; bool mpath; bool fdb_nh; bool has_v4; struct nh_grp_entry nh_entries[]; }; But its offset within 'struct nexthop' is also taken into account to determine the allocation size. Instead, use struct_size() to allocate only the required number of bytes. Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-08-22net: nexthop: don't allow empty NHA_GROUPNikolay Aleksandrov
Currently the nexthop code will use an empty NHA_GROUP attribute, but it requires at least 1 entry in order to function properly. Otherwise we end up derefencing null or random pointers all over the place due to not having any nh_grp_entry members allocated, nexthop code relies on having at least the first member present. Empty NHA_GROUP doesn't make any sense so just disallow it. Also add a WARN_ON for any future users of nexthop_create_group(). BUG: kernel NULL pointer dereference, address: 0000000000000080 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] SMP CPU: 0 PID: 558 Comm: ip Not tainted 5.9.0-rc1+ #93 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-2.fc32 04/01/2014 RIP: 0010:fib_check_nexthop+0x4a/0xaa Code: 0f 84 83 00 00 00 48 c7 02 80 03 f7 81 c3 40 80 fe fe 75 12 b8 ea ff ff ff 48 85 d2 74 6b 48 c7 02 40 03 f7 81 c3 48 8b 40 10 <48> 8b 80 80 00 00 00 eb 36 80 78 1a 00 74 12 b8 ea ff ff ff 48 85 RSP: 0018:ffff88807983ba00 EFLAGS: 00010213 RAX: 0000000000000000 RBX: ffff88807983bc00 RCX: 0000000000000000 RDX: ffff88807983bc00 RSI: 0000000000000000 RDI: ffff88807bdd0a80 RBP: ffff88807983baf8 R08: 0000000000000dc0 R09: 000000000000040a R10: 0000000000000000 R11: ffff88807bdd0ae8 R12: 0000000000000000 R13: 0000000000000000 R14: ffff88807bea3100 R15: 0000000000000001 FS: 00007f10db393700(0000) GS:ffff88807dc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000080 CR3: 000000007bd0f004 CR4: 00000000003706f0 Call Trace: fib_create_info+0x64d/0xaf7 fib_table_insert+0xf6/0x581 ? __vma_adjust+0x3b6/0x4d4 inet_rtm_newroute+0x56/0x70 rtnetlink_rcv_msg+0x1e3/0x20d ? rtnl_calcit.isra.0+0xb8/0xb8 netlink_rcv_skb+0x5b/0xac netlink_unicast+0xfa/0x17b netlink_sendmsg+0x334/0x353 sock_sendmsg_nosec+0xf/0x3f ____sys_sendmsg+0x1a0/0x1fc ? copy_msghdr_from_user+0x4c/0x61 ___sys_sendmsg+0x63/0x84 ? handle_mm_fault+0xa39/0x11b5 ? sockfd_lookup_light+0x72/0x9a __sys_sendmsg+0x50/0x6e do_syscall_64+0x54/0xbe entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f10dacc0bb7 Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb cd 66 0f 1f 44 00 00 8b 05 9a 4b 2b 00 85 c0 75 2e 48 63 ff 48 63 d2 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 8b 15 b1 f2 2a 00 f7 d8 64 89 02 48 RSP: 002b:00007ffcbe628bf8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007ffcbe628f80 RCX: 00007f10dacc0bb7 RDX: 0000000000000000 RSI: 00007ffcbe628c60 RDI: 0000000000000003 RBP: 000000005f41099c R08: 0000000000000001 R09: 0000000000000008 R10: 00000000000005e9 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007ffcbe628d70 R15: 0000563a86c6e440 Modules linked in: CR2: 0000000000000080 CC: David Ahern <dsahern@gmail.com> Fixes: 430a049190de ("nexthop: Add support for nexthop groups") Reported-by: syzbot+a61aa19b0c14c8770bd9@syzkaller.appspotmail.com Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-10nexthop: Fix fdb labeling for groupsDavid Ahern
fdb nexthops are marked with a flag. For standalone nexthops, a flag was added to the nh_info struct. For groups that flag was added to struct nexthop when it should have been added to the group information. Fix by removing the flag from the nexthop struct and adding a flag to nh_group that mirrors nh_info and is really only a caching of the individual types. Add a helper, nexthop_is_fdb, for use by the vxlan code and fixup the internal code to use the flag from either nh_info or nh_group. v2 - propagate fdb_nh in remove_nh_grp_entry Fixes: 38428d68719c ("nexthop: support for fdb ecmp nexthops") Cc: Roopa Prabhu <roopa@cumulusnetworks.com> Signed-off-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-01ipv4: nexthop: Fix deadcode issue by performing a proper NULL checkPatrick Eigensatz
After allocating the spare nexthop group it should be tested for kzalloc() returning NULL, instead the already used nexthop group (which cannot be NULL at this point) had been tested so far. Additionally, if kzalloc() fails, return ERR_PTR(-ENOMEM) instead of NULL. Coverity-id: 1463885 Reported-by: Coverity <scan-admin@coverity.com> Signed-off-by: Patrick Eigensatz <patrickeigensatz@gmail.com> Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-31Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netDavid S. Miller
xdp_umem.c had overlapping changes between the 64-bit math fix for the calculation of npgs and the removal of the zerocopy memory type which got rid of the chunk_size_nohdr member. The mlx5 Kconfig conflict is a case where we just take the net-next copy of the Kconfig entry dependency as it takes on the ESWITCH dependency by one level of indirection which is what the 'net' conflicting change is trying to ensure. Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-27nexthop: Fix type of event_type in call_nexthop_notifiersNathan Chancellor
Clang warns: net/ipv4/nexthop.c:841:30: warning: implicit conversion from enumeration type 'enum nexthop_event_type' to different enumeration type 'enum fib_event_type' [-Wenum-conversion] call_nexthop_notifiers(net, NEXTHOP_EVENT_DEL, nh); ~~~~~~~~~~~~~~~~~~~~~~ ^~~~~~~~~~~~~~~~~ 1 warning generated. Use the right type for event_type so that clang does not warn. Fixes: 8590ceedb701 ("nexthop: add support for notifiers") Link: https://github.com/ClangBuiltLinux/linux/issues/1038 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-26nexthops: don't modify published nexthop groupsNikolay Aleksandrov
We must avoid modifying published nexthop groups while they might be in use, otherwise we might see NULL ptr dereferences. In order to do that we allocate 2 nexthoup group structures upon nexthop creation and swap between them when we have to delete an entry. The reason is that we can't fail nexthop group removal, so we can't handle allocation failure thus we move the extra allocation on creation where we can safely fail and return ENOMEM. Fixes: 430a049190de ("nexthop: Add support for nexthop groups") Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-26nexthops: Move code from remove_nexthop_from_groups to remove_nh_grp_entryDavid Ahern
Move nh_grp dereference and check for removing nexthop group due to all members gone into remove_nh_grp_entry. Fixes: 430a049190de ("nexthop: Add support for nexthop groups") Signed-off-by: David Ahern <dsahern@gmail.com> Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.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>
2020-05-22nexthop: add support for notifiersRoopa Prabhu
This patch adds nexthop add/del notifiers. To be used by vxlan driver in a later patch. Could possibly be used by switchdev drivers in the future. Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-22nexthop: support for fdb ecmp nexthopsRoopa Prabhu
This patch introduces ecmp nexthops and nexthop groups for mac fdb entries. In subsequent patches this is used by the vxlan driver fdb entries. The use case is E-VPN multihoming [1,2,3] which requires bridged vxlan traffic to be load balanced to remote switches (vteps) belonging to the same multi-homed ethernet segment (This is analogous to a multi-homed LAG but over vxlan). Changes include new nexthop flag NHA_FDB for nexthops referenced by fdb entries. These nexthops only have ip. This patch includes appropriate checks to avoid routes referencing such nexthops. example: $ip nexthop add id 12 via 172.16.1.2 fdb $ip nexthop add id 13 via 172.16.1.3 fdb $ip nexthop add id 102 group 12/13 fdb $bridge fdb add 02:02:00:00:00:13 dev vxlan1000 nhid 101 self [1] E-VPN https://tools.ietf.org/html/rfc7432 [2] E-VPN VxLAN: https://tools.ietf.org/html/rfc8365 [3] LPC talk with mention of nexthop groups for L2 ecmp http://vger.kernel.org/lpc_net2018_talks/scaling_bridge_fdb_database_slidesV3.pdf v4 - fixed uninitialized variable reported by kernel test robot Reported-by: kernel test robot <rong.a.chen@intel.com> Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-20net: nlmsg_cancel() if put fails for nhmsgStephen Worley
Fixes data remnant seen when we fail to reserve space for a nexthop group during a larger dump. If we fail the reservation, we goto nla_put_failure and cancel the message. Reproduce with the following iproute2 commands: ===================== ip link add dummy1 type dummy ip link add dummy2 type dummy ip link add dummy3 type dummy ip link add dummy4 type dummy ip link add dummy5 type dummy ip link add dummy6 type dummy ip link add dummy7 type dummy ip link add dummy8 type dummy ip link add dummy9 type dummy ip link add dummy10 type dummy ip link add dummy11 type dummy ip link add dummy12 type dummy ip link add dummy13 type dummy ip link add dummy14 type dummy ip link add dummy15 type dummy ip link add dummy16 type dummy ip link add dummy17 type dummy ip link add dummy18 type dummy ip link add dummy19 type dummy ip link add dummy20 type dummy ip link add dummy21 type dummy ip link add dummy22 type dummy ip link add dummy23 type dummy ip link add dummy24 type dummy ip link add dummy25 type dummy ip link add dummy26 type dummy ip link add dummy27 type dummy ip link add dummy28 type dummy ip link add dummy29 type dummy ip link add dummy30 type dummy ip link add dummy31 type dummy ip link add dummy32 type dummy ip link set dummy1 up ip link set dummy2 up ip link set dummy3 up ip link set dummy4 up ip link set dummy5 up ip link set dummy6 up ip link set dummy7 up ip link set dummy8 up ip link set dummy9 up ip link set dummy10 up ip link set dummy11 up ip link set dummy12 up ip link set dummy13 up ip link set dummy14 up ip link set dummy15 up ip link set dummy16 up ip link set dummy17 up ip link set dummy18 up ip link set dummy19 up ip link set dummy20 up ip link set dummy21 up ip link set dummy22 up ip link set dummy23 up ip link set dummy24 up ip link set dummy25 up ip link set dummy26 up ip link set dummy27 up ip link set dummy28 up ip link set dummy29 up ip link set dummy30 up ip link set dummy31 up ip link set dummy32 up ip link set dummy33 up ip link set dummy34 up ip link set vrf-red up ip link set vrf-blue up ip link set dummyVRFred up ip link set dummyVRFblue up ip ro add 1.1.1.1/32 dev dummy1 ip ro add 1.1.1.2/32 dev dummy2 ip ro add 1.1.1.3/32 dev dummy3 ip ro add 1.1.1.4/32 dev dummy4 ip ro add 1.1.1.5/32 dev dummy5 ip ro add 1.1.1.6/32 dev dummy6 ip ro add 1.1.1.7/32 dev dummy7 ip ro add 1.1.1.8/32 dev dummy8 ip ro add 1.1.1.9/32 dev dummy9 ip ro add 1.1.1.10/32 dev dummy10 ip ro add 1.1.1.11/32 dev dummy11 ip ro add 1.1.1.12/32 dev dummy12 ip ro add 1.1.1.13/32 dev dummy13 ip ro add 1.1.1.14/32 dev dummy14 ip ro add 1.1.1.15/32 dev dummy15 ip ro add 1.1.1.16/32 dev dummy16 ip ro add 1.1.1.17/32 dev dummy17 ip ro add 1.1.1.18/32 dev dummy18 ip ro add 1.1.1.19/32 dev dummy19 ip ro add 1.1.1.20/32 dev dummy20 ip ro add 1.1.1.21/32 dev dummy21 ip ro add 1.1.1.22/32 dev dummy22 ip ro add 1.1.1.23/32 dev dummy23 ip ro add 1.1.1.24/32 dev dummy24 ip ro add 1.1.1.25/32 dev dummy25 ip ro add 1.1.1.26/32 dev dummy26 ip ro add 1.1.1.27/32 dev dummy27 ip ro add 1.1.1.28/32 dev dummy28 ip ro add 1.1.1.29/32 dev dummy29 ip ro add 1.1.1.30/32 dev dummy30 ip ro add 1.1.1.31/32 dev dummy31 ip ro add 1.1.1.32/32 dev dummy32 ip next add id 1 via 1.1.1.1 dev dummy1 ip next add id 2 via 1.1.1.2 dev dummy2 ip next add id 3 via 1.1.1.3 dev dummy3 ip next add id 4 via 1.1.1.4 dev dummy4 ip next add id 5 via 1.1.1.5 dev dummy5 ip next add id 6 via 1.1.1.6 dev dummy6 ip next add id 7 via 1.1.1.7 dev dummy7 ip next add id 8 via 1.1.1.8 dev dummy8 ip next add id 9 via 1.1.1.9 dev dummy9 ip next add id 10 via 1.1.1.10 dev dummy10 ip next add id 11 via 1.1.1.11 dev dummy11 ip next add id 12 via 1.1.1.12 dev dummy12 ip next add id 13 via 1.1.1.13 dev dummy13 ip next add id 14 via 1.1.1.14 dev dummy14 ip next add id 15 via 1.1.1.15 dev dummy15 ip next add id 16 via 1.1.1.16 dev dummy16 ip next add id 17 via 1.1.1.17 dev dummy17 ip next add id 18 via 1.1.1.18 dev dummy18 ip next add id 19 via 1.1.1.19 dev dummy19 ip next add id 20 via 1.1.1.20 dev dummy20 ip next add id 21 via 1.1.1.21 dev dummy21 ip next add id 22 via 1.1.1.22 dev dummy22 ip next add id 23 via 1.1.1.23 dev dummy23 ip next add id 24 via 1.1.1.24 dev dummy24 ip next add id 25 via 1.1.1.25 dev dummy25 ip next add id 26 via 1.1.1.26 dev dummy26 ip next add id 27 via 1.1.1.27 dev dummy27 ip next add id 28 via 1.1.1.28 dev dummy28 ip next add id 29 via 1.1.1.29 dev dummy29 ip next add id 30 via 1.1.1.30 dev dummy30 ip next add id 31 via 1.1.1.31 dev dummy31 ip next add id 32 via 1.1.1.32 dev dummy32 i=100 while [ $i -le 200 ] do ip next add id $i group 1/2/3/4/5/6/7/8/9/10/11/12/13/14/15/16/17/18/19 echo $i ((i++)) done ip next add id 999 group 1/2/3/4/5/6 ip next ls ======================== Fixes: ab84be7e54fc ("net: Initial nexthop code") Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-17nexthop: Fix attribute checking for groupsDavid Ahern
For nexthop groups, attributes after NHA_GROUP_TYPE are invalid, but nh_check_attr_group starts checking at NHA_GROUP. The group type defaults to multipath and the NHA_GROUP_TYPE is currently optional so this has slipped through so far. Fix the attribute checking to handle support of new group types. Fixes: 430a049190de ("nexthop: Add support for nexthop groups") Signed-off-by: ASSOGBA Emery <assogba.emery@gmail.com> Signed-off-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>
2020-04-28net: ipv6: new arg skip_notify to ip6_rt_delRoopa Prabhu
Used in subsequent work to skip route delete notifications on nexthop deletes. Suggested-by: David Ahern <dsahern@gmail.com> Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-12inet: 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>
2020-01-27net: include struct nhmsg size in nh nlmsg sizeStephen Worley
Include the size of struct nhmsg size when calculating how much of a payload to allocate in a new netlink nexthop notification message. Without this, we will fail to fill the skbuff at certain nexthop group sizes. You can reproduce the failure with the following iproute2 commands: ip link add dummy1 type dummy ip link add dummy2 type dummy ip link add dummy3 type dummy ip link add dummy4 type dummy ip link add dummy5 type dummy ip link add dummy6 type dummy ip link add dummy7 type dummy ip link add dummy8 type dummy ip link add dummy9 type dummy ip link add dummy10 type dummy ip link add dummy11 type dummy ip link add dummy12 type dummy ip link add dummy13 type dummy ip link add dummy14 type dummy ip link add dummy15 type dummy ip link add dummy16 type dummy ip link add dummy17 type dummy ip link add dummy18 type dummy ip link add dummy19 type dummy ip ro add 1.1.1.1/32 dev dummy1 ip ro add 1.1.1.2/32 dev dummy2 ip ro add 1.1.1.3/32 dev dummy3 ip ro add 1.1.1.4/32 dev dummy4 ip ro add 1.1.1.5/32 dev dummy5 ip ro add 1.1.1.6/32 dev dummy6 ip ro add 1.1.1.7/32 dev dummy7 ip ro add 1.1.1.8/32 dev dummy8 ip ro add 1.1.1.9/32 dev dummy9 ip ro add 1.1.1.10/32 dev dummy10 ip ro add 1.1.1.11/32 dev dummy11 ip ro add 1.1.1.12/32 dev dummy12 ip ro add 1.1.1.13/32 dev dummy13 ip ro add 1.1.1.14/32 dev dummy14 ip ro add 1.1.1.15/32 dev dummy15 ip ro add 1.1.1.16/32 dev dummy16 ip ro add 1.1.1.17/32 dev dummy17 ip ro add 1.1.1.18/32 dev dummy18 ip ro add 1.1.1.19/32 dev dummy19 ip next add id 1 via 1.1.1.1 dev dummy1 ip next add id 2 via 1.1.1.2 dev dummy2 ip next add id 3 via 1.1.1.3 dev dummy3 ip next add id 4 via 1.1.1.4 dev dummy4 ip next add id 5 via 1.1.1.5 dev dummy5 ip next add id 6 via 1.1.1.6 dev dummy6 ip next add id 7 via 1.1.1.7 dev dummy7 ip next add id 8 via 1.1.1.8 dev dummy8 ip next add id 9 via 1.1.1.9 dev dummy9 ip next add id 10 via 1.1.1.10 dev dummy10 ip next add id 11 via 1.1.1.11 dev dummy11 ip next add id 12 via 1.1.1.12 dev dummy12 ip next add id 13 via 1.1.1.13 dev dummy13 ip next add id 14 via 1.1.1.14 dev dummy14 ip next add id 15 via 1.1.1.15 dev dummy15 ip next add id 16 via 1.1.1.16 dev dummy16 ip next add id 17 via 1.1.1.17 dev dummy17 ip next add id 18 via 1.1.1.18 dev dummy18 ip next add id 19 via 1.1.1.19 dev dummy19 ip next add id 1111 group 1/2/3/4/5/6/7/8/9/10/11/12/13/14/15/16/17/18/19 ip next del id 1111 Fixes: 430a049190de ("nexthop: Add support for nexthop groups") Signed-off-by: Stephen Worley <sworley@cumulusnetworks.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-21net: remove the unnecessary strict_start_type in some policiesXin Long
ct_policy and mpls_policy are parsed with nla_parse_nested(), which does NL_VALIDATE_STRICT validation, strict_start_type is not needed to set as it is actually trying to make some attributes parsed with NL_VALIDATE_STRICT. This patch is to remove it, and do the same on rtm_nh_policy which is parsed by nlmsg_parse(). Suggested-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Xin Long <lucien.xin@gmail.com> Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-22nexthops: remove redundant assignment to variable errColin Ian King
Variable err is initialized to a value that is never read and it is re-assigned later. The initialization is redundant and can be removed. Addresses-Coverity: ("Unused Value") Signed-off-by: Colin Ian King <colin.king@canonical.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-10nexthops: add support for replaceDavid Ahern
Add support for atomically upating a nexthop config. When updating a nexthop, walk the lists of associated fib entries and verify the new config is valid. Replace is done by swapping nh_info for single nexthops - new config is applied to old nexthop struct, and old config is moved to new nexthop struct. For nexthop groups the same applies but for nh_group. In addition for groups the nh_parent reference needs to be updated. The old config is released by calling __remove_nexthop on the 'new' nexthop which now has the old config. This is done to avoid messing around with the list_heads that track which fib entries are using the nexthop. After the swap of config data, bump the sequence counters for FIB entries to invalidate any dst entries and send notifications to userspace. The notifications include the new nexthop spec as well as any fib entries using the updated nexthop struct. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-10nexthops: Add ipv6 helper to walk all fib6_nh in a nexthop structDavid Ahern
IPv6 has traditionally had a single fib6_nh per fib6_info. With nexthops we can have multiple fib6_nh associated with a fib6_info. Add a nexthop helper to invoke a callback for each fib6_nh in a 'struct nexthop'. If the callback returns non-0, the loop is stopped and the return value passed to the caller. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-04ipv6: Plumb support for nexthop object in a fib6_infoDavid Ahern
Add struct nexthop and nh_list list_head to fib6_info. nh_list is the fib6_info side of the nexthop <-> fib_info relationship. Since a fib6_info referencing a nexthop object can not have 'sibling' entries (the old way of doing multipath routes), the nh_list is a union with fib6_siblings. Add f6i_list list_head to 'struct nexthop' to track fib6_info entries using a nexthop instance. Update __remove_nexthop_fib to walk f6_list and delete fib entries using the nexthop. Add a few nexthop helpers for use when a nexthop is added to fib6_info: - nexthop_fib6_nh - return first fib6_nh in a nexthop object - fib6_info_nh_dev moved to nexthop.h and updated to use nexthop_fib6_nh if the fib6_info references a nexthop object - nexthop_path_fib6_result - similar to ipv4, select a path within a multipath nexthop object. If the nexthop is a blackhole, set fib6_result type to RTN_BLACKHOLE, and set the REJECT flag Update the fib6_info references to check for nh and take a different path as needed: - rt6_qualify_for_ecmp - if a fib entry uses a nexthop object it can NOT be coalesced with other fib entries into a multipath route - rt6_duplicate_nexthop - use nexthop_cmp if either fib6_info references a nexthop - addrconf (host routes), RA's and info entries (anything configured via ndisc) does not use nexthop objects - fib6_info_destroy_rcu - put reference to nexthop object - fib6_purge_rt - drop fib6_info from f6i_list - fib6_select_path - update to use the new nexthop_path_fib6_result when fib entry uses a nexthop object - rt6_device_match - update to catch use of nexthop object as a blackhole and set fib6_type and flags. - ip6_route_info_create - don't add space for fib6_nh if fib entry is going to reference a nexthop object, take a reference to nexthop object, disallow use of source routing - rt6_nlmsg_size - add space for RTA_NH_ID - add rt6_fill_node_nexthop to add nexthop data on a dump As with ipv4, most of the changes push existing code into the else branch of whether the fib entry uses a nexthop object. Update the nexthop code to walk f6i_list on a nexthop deleted to remove fib entries referencing it. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-04ipv4: Plumb support for nexthop object in a fib_infoDavid Ahern
Add 'struct nexthop' and nh_list list_head to fib_info. nh_list is the fib_info side of the nexthop <-> fib_info relationship. Add fi_list list_head to 'struct nexthop' to track fib_info entries using a nexthop instance. Add __remove_nexthop_fib and add it to __remove_nexthop to walk the new list_head and mark those fib entries as dead when the nexthop is deleted. Add a few nexthop helpers for use when a nexthop is added to fib_info: - nexthop_cmp to determine if 2 nexthops are the same - nexthop_path_fib_result to select a path for a multipath 'struct nexthop' - nexthop_fib_nhc to select a specific fib_nh_common within a multipath 'struct nexthop' Update existing fib_info_nhc to use nexthop_fib_nhc if a fib_info uses a 'struct nexthop', and mark fib_info_nh as only used for the non-nexthop case. Update the fib_info functions to check for fi->nh and take a different path as needed: - free_fib_info_rcu - put the nexthop object reference - fib_release_info - remove the fib_info from the nexthop's fi_list - nh_comp - use nexthop_cmp when either fib_info references a nexthop object - fib_info_hashfn - use the nexthop id for the hashing vs the oif of each fib_nh in a fib_info - fib_nlmsg_size - add space for the RTA_NH_ID attribute - fib_create_info - verify nexthop reference can be taken, verify nexthop spec is valid for fib entry, and add fib_info to fi_list for a nexthop - fib_select_multipath - use the new nexthop_path_fib_result to select a path when nexthop objects are used - fib_table_lookup - if the 'struct nexthop' is a blackhole nexthop, treat it the same as a fib entry using 'blackhole' The bulk of the changes are in fib_semantics.c and most of that is moving the existing change_nexthops into an else branch. Update the nexthop code to walk fi_list on a nexthop deleted to remove fib entries referencing it. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-04ipv4: Prepare for fib6_nh from a nexthop objectDavid Ahern
Convert more IPv4 code to use fib_nh_common over fib_nh to enable routes to use a fib6_nh based nexthop. In the end, only code not using a nexthop object in a fib_info should directly access fib_nh in a fib_info without checking the famiy and going through fib_nh_common. Those functions will be marked when it is not directly evident. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-31nexthop: remove redundant assignment to errColin Ian King
The variable err is initialized with a value that is never read and err is reassigned a few statements later. This initialization is redundant and can be removed. Addresses-Coverity: ("Unused value") Signed-off-by: Colin Ian King <colin.king@canonical.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-28nexthop: Add support for nexthop groupsDavid Ahern
Allow the creation of nexthop groups which reference other nexthop objects to create multipath routes: +--------------+ +------------+ +--------------+ | | nh nh_grp --->| nh_grp_entry |-+ +------------+ +---------|----+ ^ | | +------------+ +----------------+ +--->| nh, weight | nh_parent +------------+ A group entry points to a nexthop with a weight for that hop within the group. The nexthop has a list_head, grp_list, for tracking which groups it is a member of and the group entry has a reference back to the parent. The grp_list is used when a nexthop is deleted - to efficiently remove it from groups using it. If a nexthop group spec is given, no other attributes can be set. Each nexthop id in a group spec must already exist. Similar to single nexthops, the specification of a nexthop group can be updated so that data is managed with rcu locking. Add path selection function to account for multiple paths and add ipv{4,6}_good_nh helpers to know that if a neighbor entry exists it is in a good state. Update NETDEV event handling to rebalance multipath nexthop groups if a nexthop is deleted due to a link event (down or unregister). When a nexthop is removed any groups using it are updated. Groups using a nexthop a tracked via a grp_list. Nexthop dumps can be limited to groups only by adding NHA_GROUPS to the request. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-28nexthop: Add support for lwt encapsDavid Ahern
Add support for NHA_ENCAP and NHA_ENCAP_TYPE. Leverages the existing code for lwtunnel within fib_nh_common, so the only change needed is handling the attributes in the nexthop code. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-28nexthop: Add support for IPv6 gatewaysDavid Ahern
Handle IPv6 gateway in a nexthop spec. If nh_family is set to AF_INET6, NHA_GATEWAY is expected to be an IPv6 address. Add ipv6 option to gw in nh_config to hold the address, add fib6_nh to nh_info to leverage the ipv6 initialization and cleanup code. Update nh_fill_node to dump the v6 address. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-28nexthop: Add support for IPv4 nexthopsDavid Ahern
Add support for IPv4 nexthops. If nh_family is set to AF_INET, then NHA_GATEWAY is expected to be an IPv4 address. Register for netdev events to be notified of admin up/down changes as well as deletes. A hash table is used to track nexthop per devices to quickly convert device events to the affected nexthops. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-28net: Initial nexthop codeDavid Ahern
Barebones start point for nexthops. Implementation for RTM commands, notifications, management of rbtree for holding nexthops by id, and kernel side data structures for nexthops and nexthop config. Nexthops are maintained in an rbtree sorted by id. Similar to routes, nexthops are configured per namespace using netns_nexthop struct added to struct net. Nexthop notifications are sent when a nexthop is added or deleted, but NOT if the delete is due to a device event or network namespace teardown (which also involves device events). Applications are expected to use the device down event to flush nexthops and any routes used by the nexthops. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
generated by cgit 1.2.3-korg (git 2.39.0) at 2024-07-02 03:58:28 +0000