CVE-2026-43012

medium

Published 2026-05-01 · Modified 2026-05-07

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CVSS v3

5.5

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS v4 NEW

—

not yet in upstream

VIR risk

5.5

Description

In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Fix switchdev mode rollback in case of failure If for some internal reason switchdev mode fails, we rollback to legacy mode, before this patch, rollback will unregister the uplink netdev and leave it unregistered causing the below kernel bug. To fix this, we need to avoid netdev unregister by setting the proper rollback flag 'MLX5_PRIV_FLAGS_SWITCH_LEGACY' to indicate legacy mode. devlink (431) used greatest stack depth: 11048 bytes left mlx5_core 0000:00:03.0: E-Switch: Disable: mode(LEGACY), nvfs(0), \ necvfs(0), active vports(0) mlx5_core 0000:00:03.0: E-Switch: Supported tc chains and prios offload mlx5_core 0000:00:03.0: Loading uplink representor for vport 65535 mlx5_core 0000:00:03.0: mlx5_cmd_out_err:816:(pid 456): \ QUERY_HCA_CAP(0x100) op_mod(0x0) failed, \ status bad parameter(0x3), syndrome (0x3a3846), err(-22) mlx5_core 0000:00:03.0 enp0s3np0 (unregistered): Unloading uplink \ representor for vport 65535 ------------[ cut here ]------------ kernel BUG at net/core/dev.c:12070! Oops: invalid opcode: 0000 [#1] SMP NOPTI CPU: 2 UID: 0 PID: 456 Comm: devlink Not tainted 6.16.0-rc3+ \ #9 PREEMPT(voluntary) RIP: 0010:unregister_netdevice_many_notify+0x123/0xae0 ... Call Trace: [ 90.923094] unregister_netdevice_queue+0xad/0xf0 [ 90.923323] unregister_netdev+0x1c/0x40 [ 90.923522] mlx5e_vport_rep_unload+0x61/0xc6 [ 90.923736] esw_offloads_enable+0x8e6/0x920 [ 90.923947] mlx5_eswitch_enable_locked+0x349/0x430 [ 90.924182] ? is_mp_supported+0x57/0xb0 [ 90.924376] mlx5_devlink_eswitch_mode_set+0x167/0x350 [ 90.924628] devlink_nl_eswitch_set_doit+0x6f/0xf0 [ 90.924862] genl_family_rcv_msg_doit+0xe8/0x140 [ 90.925088] genl_rcv_msg+0x18b/0x290 [ 90.925269] ? __pfx_devlink_nl_pre_doit+0x10/0x10 [ 90.925506] ? __pfx_devlink_nl_eswitch_set_doit+0x10/0x10 [ 90.925766] ? __pfx_devlink_nl_post_doit+0x10/0x10 [ 90.926001] ? __pfx_genl_rcv_msg+0x10/0x10 [ 90.926206] netlink_rcv_skb+0x52/0x100 [ 90.926393] genl_rcv+0x28/0x40 [ 90.926557] netlink_unicast+0x27d/0x3d0 [ 90.926749] netlink_sendmsg+0x1f7/0x430 [ 90.926942] __sys_sendto+0x213/0x220 [ 90.927127] ? __sys_recvmsg+0x6a/0xd0 [ 90.927312] __x64_sys_sendto+0x24/0x30 [ 90.927504] do_syscall_64+0x50/0x1c0 [ 90.927687] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 90.927929] RIP: 0033:0x7f7d0363e047

Predictions

Exploit likelihood

55%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

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OS impact

OS	Version	Status	Fixed in
sles		affected
debian	bookworm	fixed	`0`
debian	bullseye	fixed	`0`
debian	forky	fixed	`6.19.12-1`
debian	sid	fixed	`6.19.12-1`
debian	trixie	fixed	`6.12.85-1`
linux-kernel		affected	`6.12.81`
linux-kernel	6.13	affected
linux-kernel	7.0	affected

References

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.