kernel.git/drivers/net/bonding, branch linux-5.10.y

bonding: alb: fix UAF in rlb_arp_recv during bond up/down

2026-03-04T12:19:48Z

[ Upstream commit e6834a4c474697df23ab9948fd3577b26bf48656 ] The ALB RX path may access rx_hashtbl concurrently with bond teardown. During rapid bond up/down cycles, rlb_deinitialize() frees rx_hashtbl while RX handlers are still running, leading to a null pointer dereference detected by KASAN. However, the root cause is that rlb_arp_recv() can still be accessed after setting recv_probe to NULL, which is actually a use-after-free (UAF) issue. That is the reason for using the referenced commit in the Fixes tag. [ 214.174138] Oops: general protection fault, probably for non-canonical address 0xdffffc000000001d: 0000 [#1] SMP KASAN PTI [ 214.186478] KASAN: null-ptr-deref in range [0x00000000000000e8-0x00000000000000ef] [ 214.194933] CPU: 30 UID: 0 PID: 2375 Comm: ping Kdump: loaded Not tainted 6.19.0-rc8+ #2 PREEMPT(voluntary) [ 214.205907] Hardware name: Dell Inc. PowerEdge R730/0WCJNT, BIOS 2.14.0 01/14/2022 [ 214.214357] RIP: 0010:rlb_arp_recv+0x505/0xab0 [bonding] [ 214.220320] Code: 0f 85 2b 05 00 00 48 b8 00 00 00 00 00 fc ff df 40 0f b6 ed 48 c1 e5 06 49 03 ad 78 01 00 00 48 8d 7d 28 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 06 0f 8e 12 05 00 00 80 7d 28 00 0f 84 8c 00 [ 214.241280] RSP: 0018:ffffc900073d8870 EFLAGS: 00010206 [ 214.247116] RAX: dffffc0000000000 RBX: ffff888168556822 RCX: ffff88816855681e [ 214.255082] RDX: 000000000000001d RSI: dffffc0000000000 RDI: 00000000000000e8 [ 214.263048] RBP: 00000000000000c0 R08: 0000000000000002 R09: ffffed11192021c8 [ 214.271013] R10: ffff8888c9010e43 R11: 0000000000000001 R12: 1ffff92000e7b119 [ 214.278978] R13: ffff8888c9010e00 R14: ffff888168556822 R15: ffff888168556810 [ 214.286943] FS: 00007f85d2d9cb80(0000) GS:ffff88886ccb3000(0000) knlGS:0000000000000000 [ 214.295966] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 214.302380] CR2: 00007f0d047b5e34 CR3: 00000008a1c2e002 CR4: 00000000001726f0 [ 214.310347] Call Trace: [ 214.313070] [ 214.315318] ? __pfx_rlb_arp_recv+0x10/0x10 [bonding] [ 214.320975] bond_handle_frame+0x166/0xb60 [bonding] [ 214.326537] ? __pfx_bond_handle_frame+0x10/0x10 [bonding] [ 214.332680] __netif_receive_skb_core.constprop.0+0x576/0x2710 [ 214.339199] ? __pfx_arp_process+0x10/0x10 [ 214.343775] ? sched_balance_find_src_group+0x98/0x630 [ 214.349513] ? __pfx___netif_receive_skb_core.constprop.0+0x10/0x10 [ 214.356513] ? arp_rcv+0x307/0x690 [ 214.360311] ? __pfx_arp_rcv+0x10/0x10 [ 214.364499] ? __lock_acquire+0x58c/0xbd0 [ 214.368975] __netif_receive_skb_one_core+0xae/0x1b0 [ 214.374518] ? __pfx___netif_receive_skb_one_core+0x10/0x10 [ 214.380743] ? lock_acquire+0x10b/0x140 [ 214.385026] process_backlog+0x3f1/0x13a0 [ 214.389502] ? process_backlog+0x3aa/0x13a0 [ 214.394174] __napi_poll.constprop.0+0x9f/0x370 [ 214.399233] net_rx_action+0x8c1/0xe60 [ 214.403423] ? __pfx_net_rx_action+0x10/0x10 [ 214.408193] ? lock_acquire.part.0+0xbd/0x260 [ 214.413058] ? sched_clock_cpu+0x6c/0x540 [ 214.417540] ? mark_held_locks+0x40/0x70 [ 214.421920] handle_softirqs+0x1fd/0x860 [ 214.426302] ? __pfx_handle_softirqs+0x10/0x10 [ 214.431264] ? __neigh_event_send+0x2d6/0xf50 [ 214.436131] do_softirq+0xb1/0xf0 [ 214.439830] The issue is reproducible by repeatedly running ip link set bond0 up/down while receiving ARP messages, where rlb_arp_recv() can race with rlb_deinitialize() and dereference a freed rx_hashtbl entry. Fix this by setting recv_probe to NULL and then calling synchronize_net() to wait for any concurrent RX processing to finish. This ensures that no RX handler can access rx_hashtbl after it is freed in bond_alb_deinitialize(). Reported-by: Liang Li Fixes: 3aba891dde38 ("bonding: move processing of recv handlers into handle_frame()") Reviewed-by: Nikolay Aleksandrov Acked-by: Jay Vosburgh Signed-off-by: Hangbin Liu Link: https://patch.msgid.link/20260218060919.101574-1-liuhangbin@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

bonding: only set speed/duplex to unknown, if getting speed failed

2026-03-04T12:19:35Z

[ Upstream commit 48dec8d88af96039a4a17b8c2f148f2a4066e195 ] bond_update_speed_duplex() first set speed/duplex to unknown and then asks slave driver for current speed/duplex. Since getting speed/duplex might take longer there is a race, where this false state is visible by /proc/net/bonding. With commit 691b2bf14946 ("bonding: update port speed when getting bond speed") this race gets more visible, if user space is calling ethtool on a regular base. Fix this by only setting speed/duplex to unknown, if link speed is really unknown/unusable. Fixes: 98f41f694f46 ("bonding:update speed/duplex for NETDEV_CHANGE") Signed-off-by: Thomas Bogendoerfer Acked-by: Jay Vosburgh Reviewed-by: Nikolay Aleksandrov Reviewed-by: Hangbin Liu Link: https://patch.msgid.link/20260203141153.51581-1-tbogendoerfer@suse.de Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

bonding: provide a net pointer to __skb_flow_dissect()

2026-02-06T15:40:06Z

commit 5f9b329096596b7e53e07d041d7fca4cbe1be752 upstream. After 3cbf4ffba5ee ("net: plumb network namespace into __skb_flow_dissect") we have to provide a net pointer to __skb_flow_dissect(), either via skb->dev, skb->sk, or a user provided pointer. In the following case, syzbot was able to cook a bare skb. WARNING: net/core/flow_dissector.c:1131 at __skb_flow_dissect+0xb57/0x68b0 net/core/flow_dissector.c:1131, CPU#1: syz.2.1418/11053 Call Trace: bond_flow_dissect drivers/net/bonding/bond_main.c:4093 [inline] __bond_xmit_hash+0x2d7/0xba0 drivers/net/bonding/bond_main.c:4157 bond_xmit_hash_xdp drivers/net/bonding/bond_main.c:4208 [inline] bond_xdp_xmit_3ad_xor_slave_get drivers/net/bonding/bond_main.c:5139 [inline] bond_xdp_get_xmit_slave+0x1fd/0x710 drivers/net/bonding/bond_main.c:5515 xdp_master_redirect+0x13f/0x2c0 net/core/filter.c:4388 bpf_prog_run_xdp include/net/xdp.h:700 [inline] bpf_test_run+0x6b2/0x7d0 net/bpf/test_run.c:421 bpf_prog_test_run_xdp+0x795/0x10e0 net/bpf/test_run.c:1390 bpf_prog_test_run+0x2c7/0x340 kernel/bpf/syscall.c:4703 __sys_bpf+0x562/0x860 kernel/bpf/syscall.c:6182 __do_sys_bpf kernel/bpf/syscall.c:6274 [inline] __se_sys_bpf kernel/bpf/syscall.c:6272 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:6272 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94 Fixes: 58deb77cc52d ("bonding: balance ICMP echoes in layer3+4 mode") Reported-by: syzbot+c46409299c70a221415e@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/696faa23.050a0220.4cb9c.001f.GAE@google.com/T/#u Signed-off-by: Eric Dumazet Cc: Matteo Croce Acked-by: Stanislav Fomichev Link: https://patch.msgid.link/20260120161744.1893263-1-edumazet@google.com Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman

net: bonding: fix possible peer notify event loss or dup issue

2025-10-29T13:01:22Z

commit 10843e1492e474c02b91314963161731fa92af91 upstream. If the send_peer_notif counter and the peer event notify are not synchronized. It may cause problems such as the loss or dup of peer notify event. Before this patch: - If should_notify_peers is true and the lock for send_peer_notif-- fails, peer event may be sent again in next mii_monitor loop, because should_notify_peers is still true. - If should_notify_peers is true and the lock for send_peer_notif-- succeeded, but the lock for peer event fails, the peer event will be lost. This patch locks the RTNL for send_peer_notif, events, and commit simultaneously. Fixes: 07a4ddec3ce9 ("bonding: add an option to specify a delay between peer notifications") Cc: Jay Vosburgh Cc: Andrew Lunn Cc: Eric Dumazet Cc: Jakub Kicinski Cc: Paolo Abeni Cc: Hangbin Liu Cc: Nikolay Aleksandrov Cc: Vincent Bernat Cc: Signed-off-by: Tonghao Zhang Acked-by: Jay Vosburgh Link: https://patch.msgid.link/20251021050933.46412-1-tonghao@bamaicloud.com Signed-off-by: Paolo Abeni Signed-off-by: Greg Kroah-Hartman

bonding: report duplicate MAC address in all situations

2025-06-04T12:37:03Z

[ Upstream commit 28d68d396a1cd21591e8c6d74afbde33a7ea107e ] Normally, a bond uses the MAC address of the first added slave as the bond’s MAC address. And the bond will set active slave’s MAC address to bond’s address if fail_over_mac is set to none (0) or follow (2). When the first slave is removed, the bond will still use the removed slave’s MAC address, which can lead to a duplicate MAC address and potentially cause issues with the switch. To avoid confusion, let's warn the user in all situations, including when fail_over_mac is set to 2 or not in active-backup mode. Signed-off-by: Hangbin Liu Reviewed-by: Nikolay Aleksandrov Link: https://patch.msgid.link/20250225033914.18617-1-liuhangbin@gmail.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin

bonding: Fix feature propagation of NETIF_F_GSO_ENCAP_ALL

2024-12-19T17:06:11Z

[ Upstream commit 77b11c8bf3a228d1c63464534c2dcc8d9c8bf7ff ] Drivers like mlx5 expose NIC's vlan_features such as NETIF_F_GSO_UDP_TUNNEL & NETIF_F_GSO_UDP_TUNNEL_CSUM which are later not propagated when the underlying devices are bonded and a vlan device created on top of the bond. Right now, the more cumbersome workaround for this is to create the vlan on top of the mlx5 and then enslave the vlan devices to a bond. To fix this, add NETIF_F_GSO_ENCAP_ALL to BOND_VLAN_FEATURES such that bond_compute_features() can probe and propagate the vlan_features from the slave devices up to the vlan device. Given the following bond: # ethtool -i enp2s0f{0,1}np{0,1} driver: mlx5_core [...] # ethtool -k enp2s0f0np0 | grep udp tx-udp_tnl-segmentation: on tx-udp_tnl-csum-segmentation: on tx-udp-segmentation: on rx-udp_tunnel-port-offload: on rx-udp-gro-forwarding: off # ethtool -k enp2s0f1np1 | grep udp tx-udp_tnl-segmentation: on tx-udp_tnl-csum-segmentation: on tx-udp-segmentation: on rx-udp_tunnel-port-offload: on rx-udp-gro-forwarding: off # ethtool -k bond0 | grep udp tx-udp_tnl-segmentation: on tx-udp_tnl-csum-segmentation: on tx-udp-segmentation: on rx-udp_tunnel-port-offload: off [fixed] rx-udp-gro-forwarding: off Before: # ethtool -k bond0.100 | grep udp tx-udp_tnl-segmentation: off [requested on] tx-udp_tnl-csum-segmentation: off [requested on] tx-udp-segmentation: on rx-udp_tunnel-port-offload: off [fixed] rx-udp-gro-forwarding: off After: # ethtool -k bond0.100 | grep udp tx-udp_tnl-segmentation: on tx-udp_tnl-csum-segmentation: on tx-udp-segmentation: on rx-udp_tunnel-port-offload: off [fixed] rx-udp-gro-forwarding: off Various users have run into this reporting performance issues when configuring Cilium in vxlan tunneling mode and having the combination of bond & vlan for the core devices connecting the Kubernetes cluster to the outside world. Fixes: a9b3ace44c7d ("bonding: fix vlan_features computing") Signed-off-by: Daniel Borkmann Cc: Nikolay Aleksandrov Cc: Ido Schimmel Cc: Jiri Pirko Reviewed-by: Nikolay Aleksandrov Reviewed-by: Hangbin Liu Link: https://patch.msgid.link/20241210141245.327886-3-daniel@iogearbox.net Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin

net: bonding, dummy, ifb, team: advertise NETIF_F_GSO_SOFTWARE

2024-12-19T17:06:11Z

[ Upstream commit ecb8fed408b6454606bbb3cd0edb083bf0ad162a ] Virtual netdevs should use NETIF_F_GSO_SOFTWARE to forward GSO skbs as-is and let the final drivers deal with them when supported. Also remove NETIF_F_GSO_UDP_L4 from bonding and team drivers as it's now included in the "software" list. Suggested-by: Willem de Bruijn Signed-off-by: Alexander Lobakin Acked-by: Willem de Bruijn Signed-off-by: Jakub Kicinski Stable-dep-of: 77b11c8bf3a2 ("bonding: Fix feature propagation of NETIF_F_GSO_ENCAP_ALL") Signed-off-by: Sasha Levin

bonding: fix xfrm state handling when clearing active slave

2024-09-04T11:17:40Z

[ Upstream commit c4c5c5d2ef40a9f67a9241dc5422eac9ffe19547 ] If the active slave is cleared manually the xfrm state is not flushed. This leads to xfrm add/del imbalance and adding the same state multiple times. For example when the device cannot handle anymore states we get: [ 1169.884811] bond0: (slave eni0np1): bond_ipsec_add_sa_all: failed to add SA because it's filled with the same state after multiple active slave clearings. This change also has a few nice side effects: user-space gets a notification for the change, the old device gets its mac address and promisc/mcast adjusted properly. Fixes: 18cb261afd7b ("bonding: support hardware encryption offload to slaves") Signed-off-by: Nikolay Aleksandrov Reviewed-by: Hangbin Liu Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin

bonding: fix xfrm real_dev null pointer dereference

2024-09-04T11:17:40Z

[ Upstream commit f8cde9805981c50d0c029063dc7d82821806fc44 ] We shouldn't set real_dev to NULL because packets can be in transit and xfrm might call xdo_dev_offload_ok() in parallel. All callbacks assume real_dev is set. Example trace: kernel: BUG: unable to handle page fault for address: 0000000000001030 kernel: bond0: (slave eni0np1): making interface the new active one kernel: #PF: supervisor write access in kernel mode kernel: #PF: error_code(0x0002) - not-present page kernel: PGD 0 P4D 0 kernel: Oops: 0002 [#1] PREEMPT SMP kernel: CPU: 4 PID: 2237 Comm: ping Not tainted 6.7.7+ #12 kernel: Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-2.fc40 04/01/2014 kernel: RIP: 0010:nsim_ipsec_offload_ok+0xc/0x20 [netdevsim] kernel: bond0: (slave eni0np1): bond_ipsec_add_sa_all: failed to add SA kernel: Code: e0 0f 0b 48 83 7f 38 00 74 de 0f 0b 48 8b 47 08 48 8b 37 48 8b 78 40 e9 b2 e5 9a d7 66 90 0f 1f 44 00 00 48 8b 86 80 02 00 00 <83> 80 30 10 00 00 01 b8 01 00 00 00 c3 0f 1f 80 00 00 00 00 0f 1f kernel: bond0: (slave eni0np1): making interface the new active one kernel: RSP: 0018:ffffabde81553b98 EFLAGS: 00010246 kernel: bond0: (slave eni0np1): bond_ipsec_add_sa_all: failed to add SA kernel: kernel: RAX: 0000000000000000 RBX: ffff9eb404e74900 RCX: ffff9eb403d97c60 kernel: RDX: ffffffffc090de10 RSI: ffff9eb404e74900 RDI: ffff9eb3c5de9e00 kernel: RBP: ffff9eb3c0a42000 R08: 0000000000000010 R09: 0000000000000014 kernel: R10: 7974203030303030 R11: 3030303030303030 R12: 0000000000000000 kernel: R13: ffff9eb3c5de9e00 R14: ffffabde81553cc8 R15: ffff9eb404c53000 kernel: FS: 00007f2a77a3ad00(0000) GS:ffff9eb43bd00000(0000) knlGS:0000000000000000 kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 kernel: CR2: 0000000000001030 CR3: 00000001122ab000 CR4: 0000000000350ef0 kernel: bond0: (slave eni0np1): making interface the new active one kernel: Call Trace: kernel: kernel: ? __die+0x1f/0x60 kernel: bond0: (slave eni0np1): bond_ipsec_add_sa_all: failed to add SA kernel: ? page_fault_oops+0x142/0x4c0 kernel: ? do_user_addr_fault+0x65/0x670 kernel: ? kvm_read_and_reset_apf_flags+0x3b/0x50 kernel: bond0: (slave eni0np1): making interface the new active one kernel: ? exc_page_fault+0x7b/0x180 kernel: ? asm_exc_page_fault+0x22/0x30 kernel: ? nsim_bpf_uninit+0x50/0x50 [netdevsim] kernel: bond0: (slave eni0np1): bond_ipsec_add_sa_all: failed to add SA kernel: ? nsim_ipsec_offload_ok+0xc/0x20 [netdevsim] kernel: bond0: (slave eni0np1): making interface the new active one kernel: bond_ipsec_offload_ok+0x7b/0x90 [bonding] kernel: xfrm_output+0x61/0x3b0 kernel: bond0: (slave eni0np1): bond_ipsec_add_sa_all: failed to add SA kernel: ip_push_pending_frames+0x56/0x80 Fixes: 18cb261afd7b ("bonding: support hardware encryption offload to slaves") Signed-off-by: Nikolay Aleksandrov Reviewed-by: Hangbin Liu Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin

bonding: fix null pointer deref in bond_ipsec_offload_ok

2024-09-04T11:17:40Z

[ Upstream commit 95c90e4ad89d493a7a14fa200082e466e2548f9d ] We must check if there is an active slave before dereferencing the pointer. Fixes: 18cb261afd7b ("bonding: support hardware encryption offload to slaves") Signed-off-by: Nikolay Aleksandrov Reviewed-by: Hangbin Liu Reviewed-by: Eric Dumazet Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin