kernel/linux.git/net/openvswitch/actions.c, branch v6.1.168

net: openvswitch: remove never-working support for setting nsh fields

2025-12-06T21:12:39+00:00

[ Upstream commit dfe28c4167a9259fc0c372d9f9473e1ac95cff67 ] The validation of the set(nsh(...)) action is completely wrong. It runs through the nsh_key_put_from_nlattr() function that is the same function that validates NSH keys for the flow match and the push_nsh() action. However, the set(nsh(...)) has a very different memory layout. Nested attributes in there are doubled in size in case of the masked set(). That makes proper validation impossible. There is also confusion in the code between the 'masked' flag, that says that the nested attributes are doubled in size containing both the value and the mask, and the 'is_mask' that says that the value we're parsing is the mask. This is causing kernel crash on trying to write into mask part of the match with SW_FLOW_KEY_PUT() during validation, while validate_nsh() doesn't allocate any memory for it: BUG: kernel NULL pointer dereference, address: 0000000000000018 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 1c2383067 P4D 1c2383067 PUD 20b703067 PMD 0 Oops: Oops: 0000 [#1] SMP NOPTI CPU: 8 UID: 0 Kdump: loaded Not tainted 6.17.0-rc4+ #107 PREEMPT(voluntary) RIP: 0010:nsh_key_put_from_nlattr+0x19d/0x610 [openvswitch] Call Trace: validate_nsh+0x60/0x90 [openvswitch] validate_set.constprop.0+0x270/0x3c0 [openvswitch] __ovs_nla_copy_actions+0x477/0x860 [openvswitch] ovs_nla_copy_actions+0x8d/0x100 [openvswitch] ovs_packet_cmd_execute+0x1cc/0x310 [openvswitch] genl_family_rcv_msg_doit+0xdb/0x130 genl_family_rcv_msg+0x14b/0x220 genl_rcv_msg+0x47/0xa0 netlink_rcv_skb+0x53/0x100 genl_rcv+0x24/0x40 netlink_unicast+0x280/0x3b0 netlink_sendmsg+0x1f7/0x430 ____sys_sendmsg+0x36b/0x3a0 ___sys_sendmsg+0x87/0xd0 __sys_sendmsg+0x6d/0xd0 do_syscall_64+0x7b/0x2c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e The third issue with this process is that while trying to convert the non-masked set into masked one, validate_set() copies and doubles the size of the OVS_KEY_ATTR_NSH as if it didn't have any nested attributes. It should be copying each nested attribute and doubling them in size independently. And the process must be properly reversed during the conversion back from masked to a non-masked variant during the flow dump. In the end, the only two outcomes of trying to use this action are either validation failure or a kernel crash. And if somehow someone manages to install a flow with such an action, it will most definitely not do what it is supposed to, since all the keys and the masks are mixed up. Fixing all the issues is a complex task as it requires re-writing most of the validation code. Given that and the fact that this functionality never worked since introduction, let's just remove it altogether. It's better to re-introduce it later with a proper implementation instead of trying to fix it in stable releases. Fixes: b2d0f5d5dc53 ("openvswitch: enable NSH support") Reported-by: Junvy Yang Signed-off-by: Ilya Maximets Acked-by: Eelco Chaudron Reviewed-by: Aaron Conole Link: https://patch.msgid.link/20251112112246.95064-1-i.maximets@ovn.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

openvswitch: Fix unsafe attribute parsing in output_userspace()

2025-05-18T06:21:20+00:00

commit 6beb6835c1fbb3f676aebb51a5fee6b77fed9308 upstream. This patch replaces the manual Netlink attribute iteration in output_userspace() with nla_for_each_nested(), which ensures that only well-formed attributes are processed. Fixes: ccb1352e76cf ("net: Add Open vSwitch kernel components.") Signed-off-by: Eelco Chaudron Acked-by: Ilya Maximets Acked-by: Aaron Conole Link: https://patch.msgid.link/0bd65949df61591d9171c0dc13e42cea8941da10.1746541734.git.echaudro@redhat.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

tunnels: Accept PACKET_HOST in skb_tunnel_check_pmtu().

2025-04-10T12:33:40+00:00

[ Upstream commit 8930424777e43257f5bf6f0f0f53defd0d30415c ] Because skb_tunnel_check_pmtu() doesn't handle PACKET_HOST packets, commit 30a92c9e3d6b ("openvswitch: Set the skbuff pkt_type for proper pmtud support.") forced skb->pkt_type to PACKET_OUTGOING for openvswitch packets that are sent using the OVS_ACTION_ATTR_OUTPUT action. This allowed such packets to invoke the iptunnel_pmtud_check_icmp() or iptunnel_pmtud_check_icmpv6() helpers and thus trigger PMTU update on the input device. However, this also broke other parts of PMTU discovery. Since these packets don't have the PACKET_HOST type anymore, they won't trigger the sending of ICMP Fragmentation Needed or Packet Too Big messages to remote hosts when oversized (see the skb_in->pkt_type condition in __icmp_send() for example). These two skb->pkt_type checks are therefore incompatible as one requires skb->pkt_type to be PACKET_HOST, while the other requires it to be anything but PACKET_HOST. It makes sense to not trigger ICMP messages for non-PACKET_HOST packets as these messages should be generated only for incoming l2-unicast packets. However there doesn't seem to be any reason for skb_tunnel_check_pmtu() to ignore PACKET_HOST packets. Allow both cases to work by allowing skb_tunnel_check_pmtu() to work on PACKET_HOST packets and not overriding skb->pkt_type in openvswitch anymore. Fixes: 30a92c9e3d6b ("openvswitch: Set the skbuff pkt_type for proper pmtud support.") Fixes: 4cb47a8644cc ("tunnels: PMTU discovery support for directly bridged IP packets") Signed-off-by: Guillaume Nault Reviewed-by: Stefano Brivio Reviewed-by: Aaron Conole Tested-by: Aaron Conole Link: https://patch.msgid.link/eac941652b86fddf8909df9b3bf0d97bc9444793.1743208264.git.gnault@redhat.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

openvswitch: fix lockup on tx to unregistering netdev with carrier

2025-01-23T16:17:09+00:00

[ Upstream commit 47e55e4b410f7d552e43011baa5be1aab4093990 ] Commit in a fixes tag attempted to fix the issue in the following sequence of calls: do_output -> ovs_vport_send -> dev_queue_xmit -> __dev_queue_xmit -> netdev_core_pick_tx -> skb_tx_hash When device is unregistering, the 'dev->real_num_tx_queues' goes to zero and the 'while (unlikely(hash >= qcount))' loop inside the 'skb_tx_hash' becomes infinite, locking up the core forever. But unfortunately, checking just the carrier status is not enough to fix the issue, because some devices may still be in unregistering state while reporting carrier status OK. One example of such device is a net/dummy. It sets carrier ON on start, but it doesn't implement .ndo_stop to set the carrier off. And it makes sense, because dummy doesn't really have a carrier. Therefore, while this device is unregistering, it's still easy to hit the infinite loop in the skb_tx_hash() from the OVS datapath. There might be other drivers that do the same, but dummy by itself is important for the OVS ecosystem, because it is frequently used as a packet sink for tcpdump while debugging OVS deployments. And when the issue is hit, the only way to recover is to reboot. Fix that by also checking if the device is running. The running state is handled by the net core during unregistering, so it covers unregistering case better, and we don't really need to send packets to devices that are not running anyway. While only checking the running state might be enough, the carrier check is preserved. The running and the carrier states seem disjoined throughout the code and different drivers. And other core functions like __dev_direct_xmit() check both before attempting to transmit a packet. So, it seems safer to check both flags in OVS as well. Fixes: 066b86787fa3 ("net: openvswitch: fix race on port output") Reported-by: Friedrich Weber Closes: https://mail.openvswitch.org/pipermail/ovs-discuss/2025-January/053423.html Signed-off-by: Ilya Maximets Tested-by: Friedrich Weber Reviewed-by: Aaron Conole Link: https://patch.msgid.link/20250109122225.4034688-1-i.maximets@ovn.org Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

openvswitch: Set the skbuff pkt_type for proper pmtud support.

2024-06-12T09:03:51+00:00

[ Upstream commit 30a92c9e3d6b073932762bef2ac66f4ee784c657 ] Open vSwitch is originally intended to switch at layer 2, only dealing with Ethernet frames. With the introduction of l3 tunnels support, it crossed into the realm of needing to care a bit about some routing details when making forwarding decisions. If an oversized packet would need to be fragmented during this forwarding decision, there is a chance for pmtu to get involved and generate a routing exception. This is gated by the skbuff->pkt_type field. When a flow is already loaded into the openvswitch module this field is set up and transitioned properly as a packet moves from one port to another. In the case that a packet execute is invoked after a flow is newly installed this field is not properly initialized. This causes the pmtud mechanism to omit sending the required exception messages across the tunnel boundary and a second attempt needs to be made to make sure that the routing exception is properly setup. To fix this, we set the outgoing packet's pkt_type to PACKET_OUTGOING, since it can only get to the openvswitch module via a port device or packet command. Even for bridge ports as users, the pkt_type needs to be reset when doing the transmit as the packet is truly outgoing and routing needs to get involved post packet transformations, in the case of VXLAN/GENEVE/udp-tunnel packets. In general, the pkt_type on output gets ignored, since we go straight to the driver, but in the case of tunnel ports they go through IP routing layer. This issue is periodically encountered in complex setups, such as large openshift deployments, where multiple sets of tunnel traversal occurs. A way to recreate this is with the ovn-heater project that can setup a networking environment which mimics such large deployments. We need larger environments for this because we need to ensure that flow misses occur. In these environment, without this patch, we can see: ./ovn_cluster.sh start podman exec ovn-chassis-1 ip r a 170.168.0.5/32 dev eth1 mtu 1200 podman exec ovn-chassis-1 ip netns exec sw01p1 ip r flush cache podman exec ovn-chassis-1 ip netns exec sw01p1 \ ping 21.0.0.3 -M do -s 1300 -c2 PING 21.0.0.3 (21.0.0.3) 1300(1328) bytes of data. From 21.0.0.3 icmp_seq=2 Frag needed and DF set (mtu = 1142) --- 21.0.0.3 ping statistics --- ... Using tcpdump, we can also see the expected ICMP FRAG_NEEDED message is not sent into the server. With this patch, setting the pkt_type, we see the following: podman exec ovn-chassis-1 ip netns exec sw01p1 \ ping 21.0.0.3 -M do -s 1300 -c2 PING 21.0.0.3 (21.0.0.3) 1300(1328) bytes of data. From 21.0.0.3 icmp_seq=1 Frag needed and DF set (mtu = 1222) ping: local error: message too long, mtu=1222 --- 21.0.0.3 ping statistics --- ... In this case, the first ping request receives the FRAG_NEEDED message and a local routing exception is created. Tested-by: Jaime Caamano Reported-at: https://issues.redhat.com/browse/FDP-164 Fixes: 58264848a5a7 ("openvswitch: Add vxlan tunneling support.") Signed-off-by: Aaron Conole Acked-by: Eelco Chaudron Link: https://lore.kernel.org/r/20240516200941.16152-1-aconole@redhat.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin

net: openvswitch: fix race on port output

2023-04-20T10:35:09+00:00

[ Upstream commit 066b86787fa3d97b7aefb5ac0a99a22dad2d15f8 ] assume the following setup on a single machine: 1. An openvswitch instance with one bridge and default flows 2. two network namespaces "server" and "client" 3. two ovs interfaces "server" and "client" on the bridge 4. for each ovs interface a veth pair with a matching name and 32 rx and tx queues 5. move the ends of the veth pairs to the respective network namespaces 6. assign ip addresses to each of the veth ends in the namespaces (needs to be the same subnet) 7. start some http server on the server network namespace 8. test if a client in the client namespace can reach the http server when following the actions below the host has a chance of getting a cpu stuck in a infinite loop: 1. send a large amount of parallel requests to the http server (around 3000 curls should work) 2. in parallel delete the network namespace (do not delete interfaces or stop the server, just kill the namespace) there is a low chance that this will cause the below kernel cpu stuck message. If this does not happen just retry. Below there is also the output of bpftrace for the functions mentioned in the output. The series of events happening here is: 1. the network namespace is deleted calling `unregister_netdevice_many_notify` somewhere in the process 2. this sets first `NETREG_UNREGISTERING` on both ends of the veth and then runs `synchronize_net` 3. it then calls `call_netdevice_notifiers` with `NETDEV_UNREGISTER` 4. this is then handled by `dp_device_event` which calls `ovs_netdev_detach_dev` (if a vport is found, which is the case for the veth interface attached to ovs) 5. this removes the rx_handlers of the device but does not prevent packages to be sent to the device 6. `dp_device_event` then queues the vport deletion to work in background as a ovs_lock is needed that we do not hold in the unregistration path 7. `unregister_netdevice_many_notify` continues to call `netdev_unregister_kobject` which sets `real_num_tx_queues` to 0 8. port deletion continues (but details are not relevant for this issue) 9. at some future point the background task deletes the vport If after 7. but before 9. a packet is send to the ovs vport (which is not deleted at this point in time) which forwards it to the `dev_queue_xmit` flow even though the device is unregistering. In `skb_tx_hash` (which is called in the `dev_queue_xmit`) path there is a while loop (if the packet has a rx_queue recorded) that is infinite if `dev->real_num_tx_queues` is zero. To prevent this from happening we update `do_output` to handle devices without carrier the same as if the device is not found (which would be the code path after 9. is done). Additionally we now produce a warning in `skb_tx_hash` if we will hit the infinite loop. bpftrace (first word is function name): __dev_queue_xmit server: real_num_tx_queues: 1, cpu: 2, pid: 28024, tid: 28024, skb_addr: 0xffff9edb6f207000, reg_state: 1 netdev_core_pick_tx server: addr: 0xffff9f0a46d4a000 real_num_tx_queues: 1, cpu: 2, pid: 28024, tid: 28024, skb_addr: 0xffff9edb6f207000, reg_state: 1 dp_device_event server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, event 2, reg_state: 1 synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024 synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024 synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024 synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024 dp_device_event server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, event 6, reg_state: 2 ovs_netdev_detach_dev server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, reg_state: 2 netdev_rx_handler_unregister server: real_num_tx_queues: 1, cpu: 9, pid: 21024, tid: 21024, reg_state: 2 synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024 netdev_rx_handler_unregister ret server: real_num_tx_queues: 1, cpu: 9, pid: 21024, tid: 21024, reg_state: 2 dp_device_event server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, event 27, reg_state: 2 dp_device_event server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, event 22, reg_state: 2 dp_device_event server: real_num_tx_queues: 1 cpu 9, pid: 21024, tid: 21024, event 18, reg_state: 2 netdev_unregister_kobject: real_num_tx_queues: 1, cpu: 9, pid: 21024, tid: 21024 synchronize_rcu_expedited: cpu 9, pid: 21024, tid: 21024 ovs_vport_send server: real_num_tx_queues: 0, cpu: 2, pid: 28024, tid: 28024, skb_addr: 0xffff9edb6f207000, reg_state: 2 __dev_queue_xmit server: real_num_tx_queues: 0, cpu: 2, pid: 28024, tid: 28024, skb_addr: 0xffff9edb6f207000, reg_state: 2 netdev_core_pick_tx server: addr: 0xffff9f0a46d4a000 real_num_tx_queues: 0, cpu: 2, pid: 28024, tid: 28024, skb_addr: 0xffff9edb6f207000, reg_state: 2 broken device server: real_num_tx_queues: 0, cpu: 2, pid: 28024, tid: 28024 ovs_dp_detach_port server: real_num_tx_queues: 0 cpu 9, pid: 9124, tid: 9124, reg_state: 2 synchronize_rcu_expedited: cpu 9, pid: 33604, tid: 33604 stuck message: watchdog: BUG: soft lockup - CPU#5 stuck for 26s! [curl:1929279] Modules linked in: veth pktgen bridge stp llc ip_set_hash_net nft_counter xt_set nft_compat nf_tables ip_set_hash_ip ip_set nfnetlink_cttimeout nfnetlink openvswitch nsh nf_conncount nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 tls binfmt_misc nls_iso8859_1 input_leds joydev serio_raw dm_multipath scsi_dh_rdac scsi_dh_emc scsi_dh_alua sch_fq_codel drm efi_pstore 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 hid_generic usbhid hid crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel virtio_net ahci net_failover crypto_simd cryptd psmouse libahci virtio_blk failover CPU: 5 PID: 1929279 Comm: curl Not tainted 5.15.0-67-generic #74-Ubuntu Hardware name: OpenStack Foundation OpenStack Nova, BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 RIP: 0010:netdev_pick_tx+0xf1/0x320 Code: 00 00 8d 48 ff 0f b7 c1 66 39 ca 0f 86 e9 01 00 00 45 0f b7 ff 41 39 c7 0f 87 5b 01 00 00 44 29 f8 41 39 c7 0f 87 4f 01 00 00 f2 0f 1f 44 00 00 49 8b 94 24 28 04 00 00 48 85 d2 0f 84 53 01 RSP: 0018:ffffb78b40298820 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff9c8773adc2e0 RCX: 000000000000083f RDX: 0000000000000000 RSI: ffff9c8773adc2e0 RDI: ffff9c870a25e000 RBP: ffffb78b40298858 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff9c870a25e000 R13: ffff9c870a25e000 R14: ffff9c87fe043480 R15: 0000000000000000 FS: 00007f7b80008f00(0000) GS:ffff9c8e5f740000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f7b80f6a0b0 CR3: 0000000329d66000 CR4: 0000000000350ee0 Call Trace: netdev_core_pick_tx+0xa4/0xb0 __dev_queue_xmit+0xf8/0x510 ? __bpf_prog_exit+0x1e/0x30 dev_queue_xmit+0x10/0x20 ovs_vport_send+0xad/0x170 [openvswitch] do_output+0x59/0x180 [openvswitch] do_execute_actions+0xa80/0xaa0 [openvswitch] ? kfree+0x1/0x250 ? kfree+0x1/0x250 ? kprobe_perf_func+0x4f/0x2b0 ? flow_lookup.constprop.0+0x5c/0x110 [openvswitch] ovs_execute_actions+0x4c/0x120 [openvswitch] ovs_dp_process_packet+0xa1/0x200 [openvswitch] ? ovs_ct_update_key.isra.0+0xa8/0x120 [openvswitch] ? ovs_ct_fill_key+0x1d/0x30 [openvswitch] ? ovs_flow_key_extract+0x2db/0x350 [openvswitch] ovs_vport_receive+0x77/0xd0 [openvswitch] ? __htab_map_lookup_elem+0x4e/0x60 ? bpf_prog_680e8aff8547aec1_kfree+0x3b/0x714 ? trace_call_bpf+0xc8/0x150 ? kfree+0x1/0x250 ? kfree+0x1/0x250 ? kprobe_perf_func+0x4f/0x2b0 ? kprobe_perf_func+0x4f/0x2b0 ? __mod_memcg_lruvec_state+0x63/0xe0 netdev_port_receive+0xc4/0x180 [openvswitch] ? netdev_port_receive+0x180/0x180 [openvswitch] netdev_frame_hook+0x1f/0x40 [openvswitch] __netif_receive_skb_core.constprop.0+0x23d/0xf00 __netif_receive_skb_one_core+0x3f/0xa0 __netif_receive_skb+0x15/0x60 process_backlog+0x9e/0x170 __napi_poll+0x33/0x180 net_rx_action+0x126/0x280 ? ttwu_do_activate+0x72/0xf0 __do_softirq+0xd9/0x2e7 ? rcu_report_exp_cpu_mult+0x1b0/0x1b0 do_softirq+0x7d/0xb0 __local_bh_enable_ip+0x54/0x60 ip_finish_output2+0x191/0x460 __ip_finish_output+0xb7/0x180 ip_finish_output+0x2e/0xc0 ip_output+0x78/0x100 ? __ip_finish_output+0x180/0x180 ip_local_out+0x5e/0x70 __ip_queue_xmit+0x184/0x440 ? tcp_syn_options+0x1f9/0x300 ip_queue_xmit+0x15/0x20 __tcp_transmit_skb+0x910/0x9c0 ? __mod_memcg_state+0x44/0xa0 tcp_connect+0x437/0x4e0 ? ktime_get_with_offset+0x60/0xf0 tcp_v4_connect+0x436/0x530 __inet_stream_connect+0xd4/0x3a0 ? kprobe_perf_func+0x4f/0x2b0 ? aa_sk_perm+0x43/0x1c0 inet_stream_connect+0x3b/0x60 __sys_connect_file+0x63/0x70 __sys_connect+0xa6/0xd0 ? setfl+0x108/0x170 ? do_fcntl+0xe8/0x5a0 __x64_sys_connect+0x18/0x20 do_syscall_64+0x5c/0xc0 ? __x64_sys_fcntl+0xa9/0xd0 ? exit_to_user_mode_prepare+0x37/0xb0 ? syscall_exit_to_user_mode+0x27/0x50 ? do_syscall_64+0x69/0xc0 ? __sys_setsockopt+0xea/0x1e0 ? exit_to_user_mode_prepare+0x37/0xb0 ? syscall_exit_to_user_mode+0x27/0x50 ? __x64_sys_setsockopt+0x1f/0x30 ? do_syscall_64+0x69/0xc0 ? irqentry_exit+0x1d/0x30 ? exc_page_fault+0x89/0x170 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f7b8101c6a7 Code: 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2a 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 18 89 54 24 0c 48 89 34 24 89 RSP: 002b:00007ffffd6b2198 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7b8101c6a7 RDX: 0000000000000010 RSI: 00007ffffd6b2360 RDI: 0000000000000005 RBP: 0000561f1370d560 R08: 00002795ad21d1ac R09: 0030312e302e302e R10: 00007ffffd73f080 R11: 0000000000000246 R12: 0000561f1370c410 R13: 0000000000000000 R14: 0000000000000005 R15: 0000000000000000 Fixes: 7f8a436eaa2c ("openvswitch: Add conntrack action") Co-developed-by: Luca Czesla Signed-off-by: Luca Czesla Signed-off-by: Felix Huettner Reviewed-by: Eric Dumazet Reviewed-by: Simon Horman Link: https://lore.kernel.org/r/ZC0pBXBAgh7c76CA@kernel-bug-kernel-bug Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

treewide: use get_random_u32() when possible

2022-10-11T23:42:58+00:00

The prandom_u32() function has been a deprecated inline wrapper around get_random_u32() for several releases now, and compiles down to the exact same code. Replace the deprecated wrapper with a direct call to the real function. The same also applies to get_random_int(), which is just a wrapper around get_random_u32(). This was done as a basic find and replace. Reviewed-by: Greg Kroah-Hartman Reviewed-by: Kees Cook Reviewed-by: Yury Norov Reviewed-by: Jan Kara # for ext4 Acked-by: Toke Høiland-Jørgensen # for sch_cake Acked-by: Chuck Lever # for nfsd Acked-by: Jakub Kicinski Acked-by: Mika Westerberg # for thunderbolt Acked-by: Darrick J. Wong # for xfs Acked-by: Helge Deller # for parisc Acked-by: Heiko Carstens # for s390 Signed-off-by: Jason A. Donenfeld

net: openvswitch: fix misuse of the cached connection on tuple changes

2022-06-09T03:49:52+00:00

If packet headers changed, the cached nfct is no longer relevant for the packet and attempt to re-use it leads to the incorrect packet classification. This issue is causing broken connectivity in OpenStack deployments with OVS/OVN due to hairpin traffic being unexpectedly dropped. The setup has datapath flows with several conntrack actions and tuple changes between them: actions:ct(commit,zone=8,mark=0/0x1,nat(src)), set(eth(src=00:00:00:00:00:01,dst=00:00:00:00:00:06)), set(ipv4(src=172.18.2.10,dst=192.168.100.6,ttl=62)), ct(zone=8),recirc(0x4) After the first ct() action the packet headers are almost fully re-written. The next ct() tries to re-use the existing nfct entry and marks the packet as invalid, so it gets dropped later in the pipeline. Clearing the cached conntrack entry whenever packet tuple is changed to avoid the issue. The flow key should not be cleared though, because we should still be able to match on the ct_state if the recirculation happens after the tuple change but before the next ct() action. Cc: stable@vger.kernel.org Fixes: 7f8a436eaa2c ("openvswitch: Add conntrack action") Reported-by: Frode Nordahl Link: https://mail.openvswitch.org/pipermail/ovs-discuss/2022-May/051829.html Link: https://bugs.launchpad.net/ubuntu/+source/ovn/+bug/1967856 Signed-off-by: Ilya Maximets Link: https://lore.kernel.org/r/20220606221140.488984-1-i.maximets@ovn.org Signed-off-by: Jakub Kicinski

net: openvswitch: don't send internal clone attribute to the userspace.

2022-04-06T00:57:54+00:00

'OVS_CLONE_ATTR_EXEC' is an internal attribute that is used for performance optimization inside the kernel. It's added by the kernel while parsing user-provided actions and should not be sent during the flow dump as it's not part of the uAPI. The issue doesn't cause any significant problems to the ovs-vswitchd process, because reported actions are not really used in the application lifecycle and only supposed to be shown to a human via ovs-dpctl flow dump. However, the action list is still incorrect and causes the following error if the user wants to look at the datapath flows: # ovs-dpctl add-dp system@ovs-system # ovs-dpctl add-flow "" "clone(ct(commit),0)" # ovs-dpctl dump-flows , packets:0, bytes:0, used:never, actions:clone(bad length 4, expected -1 for: action0(01 00 00 00), ct(commit),0) With the fix: # ovs-dpctl dump-flows , packets:0, bytes:0, used:never, actions:clone(ct(commit),0) Additionally fixed an incorrect attribute name in the comment. Fixes: b233504033db ("openvswitch: kernel datapath clone action") Signed-off-by: Ilya Maximets Acked-by: Aaron Conole Link: https://lore.kernel.org/r/20220404104150.2865736-1-i.maximets@ovn.org Signed-off-by: Jakub Kicinski

openvswitch: Add recirc_id to recirc warning

2022-03-31T15:52:48+00:00

When hitting the recirculation limit, the kernel would currently log something like this: [ 58.586597] openvswitch: ovs-system: deferred action limit reached, drop recirc action Which isn't all that useful to debug as we only have the interface name to go on but can't track it down to a specific flow. With this change, we now instead get: [ 58.586597] openvswitch: ovs-system: deferred action limit reached, drop recirc action (recirc_id=0x9e) Which can now be correlated with the flow entries from OVS. Suggested-by: Frode Nordahl Signed-off-by: Stéphane Graber Tested-by: Stephane Graber Acked-by: Eelco Chaudron Link: https://lore.kernel.org/r/20220330194244.3476544-1-stgraber@ubuntu.com Signed-off-by: Jakub Kicinski