CVE-2026-22981

CVE-2026-22981 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-476.

Key facts

Description

In the Linux kernel, the following vulnerability has been resolved: idpf: detach and close netdevs while handling a reset Protect the reset path from callbacks by setting the netdevs to detached state and close any netdevs in UP state until the reset handling has completed. During a reset, the driver will de-allocate resources for the vport, and there is no guarantee that those will recover, which is why the existing vport_ctrl_lock does not provide sufficient protection. idpf_detach_and_close() is called right before reset handling. If the reset handling succeeds, the netdevs state is recovered via call to idpf_attach_and_open(). If the reset handling fails the netdevs remain down. The detach/down calls are protected with RTNL lock to avoid racing with callbacks. On the recovery side the attach can be done without holding the RTNL lock as there are no callbacks expected at that point, due to detach/close always being done first in that flow. The previous logic restoring the netdevs state based on the IDPF_VPORT_UP_REQUESTED flag in the init task is not needed anymore, hence the removal of idpf_set_vport_state(). The IDPF_VPORT_UP_REQUESTED is still being used to restore the state of the netdevs following the reset, but has no use outside of the reset handling flow. idpf_init_hard_reset() is converted to void, since it was used as such and there is no error handling being done based on its return value. Before this change, invoking hard and soft resets simultaneously will cause the driver to lose the vport state: ip -br a <inf> UP echo 1 > /sys/class/net/ens801f0/device/reset& \ ethtool -L ens801f0 combined 8 ip -br a <inf> DOWN ip link set <inf> up ip -br a <inf> DOWN Also in case of a failure in the reset path, the netdev is left exposed to external callbacks, while vport resources are not initialized, leading to a crash on subsequent ifup/down: [408471.398966] idpf 0000:83:00.0: HW reset detected [408471.411744] idpf 0000:83:00.0: Device HW Reset initiated [408472.277901] idpf 0000:83:00.0: The driver was unable to contact the device's firmware. Check that the FW is running. Driver state= 0x2 [408508.125551] BUG: kernel NULL pointer dereference, address: 0000000000000078 [408508.126112] #PF: supervisor read access in kernel mode [408508.126687] #PF: error_code(0x0000) - not-present page [408508.127256] PGD 2aae2f067 P4D 0 [408508.127824] Oops: Oops: 0000 [#1] SMP NOPTI ... [408508.130871] RIP: 0010:idpf_stop+0x39/0x70 [idpf] ... [408508.139193] Call Trace: [408508.139637] <TASK> [408508.140077] __dev_close_many+0xbb/0x260 [408508.140533] __dev_change_flags+0x1cf/0x280 [408508.140987] netif_change_flags+0x26/0x70 [408508.141434] dev_change_flags+0x3d/0xb0 [408508.141878] devinet_ioctl+0x460/0x890 [408508.142321] inet_ioctl+0x18e/0x1d0 [408508.142762] ? _copy_to_user+0x22/0x70 [408508.143207] sock_do_ioctl+0x3d/0xe0 [408508.143652] sock_ioctl+0x10e/0x330 [408508.144091] ? find_held_lock+0x2b/0x80 [408508.144537] __x64_sys_ioctl+0x96/0xe0 [408508.144979] do_syscall_64+0x79/0x3d0 [408508.145415] entry_SYSCALL_64_after_hwframe+0x76/0x7e [408508.145860] RIP: 0033:0x7f3e0bb4caff

Frequently asked questions

What is CVE-2026-22981?
In the Linux kernel, the following vulnerability has been resolved: idpf: detach and close netdevs while handling a reset Protect the reset path from callbacks by setting the netdevs to detached state and close any netdevs in UP state until the reset handling has completed. During a reset, the driver will de-allocate resources for the vport, and there is no guarantee that those will recover, which is why the existing vport_ctrl_lock does not provide sufficient protection. idpf_detach_and_close() is called right before reset handling. If the reset handling succeeds, the netdevs state is recovered via call to idpf_attach_and_open(). If the reset handling fails the netdevs remain down. The detach/down calls are protected with RTNL lock to avoid racing with callbacks. On the recovery side the attach can be done without holding the RTNL lock as there are no callbacks expected at that point, due to detach/close always being done first in that flow. The previous logic restoring the netdevs state based on the IDPF_VPORT_UP_REQUESTED flag in the init task is not needed anymore, hence the removal of idpf_set_vport_state(). The IDPF_VPORT_UP_REQUESTED is still being used to restore the state of the netdevs following the reset, but has no use outside of the reset handling flow. idpf_init_hard_reset() is converted to void, since it was used as such and there is no error handling being done based on its return value. Before this change, invoking hard and soft resets simultaneously will cause the driver to lose the vport state: ip -br a <inf> UP echo 1 > /sys/class/net/ens801f0/device/reset& \ ethtool -L ens801f0 combined 8 ip -br a <inf> DOWN ip link set <inf> up ip -br a <inf> DOWN Also in case of a failure in the reset path, the netdev is left exposed to external callbacks, while vport resources are not initialized, leading to a crash on subsequent ifup/down: [408471.398966] idpf 0000:83:00.0: HW reset detected [408471.411744] idpf 0000:83:00.0: Device HW Reset initiated [408472.277901] idpf 0000:83:00.0: The driver was unable to contact the device's firmware. Check that the FW is running. Driver state= 0x2 [408508.125551] BUG: kernel NULL pointer dereference, address: 0000000000000078 [408508.126112] #PF: supervisor read access in kernel mode [408508.126687] #PF: error_code(0x0000) - not-present page [408508.127256] PGD 2aae2f067 P4D 0 [408508.127824] Oops: Oops: 0000 [#1] SMP NOPTI ... [408508.130871] RIP: 0010:idpf_stop+0x39/0x70 [idpf] ... [408508.139193] Call Trace: [408508.139637] <TASK> [408508.140077] __dev_close_many+0xbb/0x260 [408508.140533] __dev_change_flags+0x1cf/0x280 [408508.140987] netif_change_flags+0x26/0x70 [408508.141434] dev_change_flags+0x3d/0xb0 [408508.141878] devinet_ioctl+0x460/0x890 [408508.142321] inet_ioctl+0x18e/0x1d0 [408508.142762] ? _copy_to_user+0x22/0x70 [408508.143207] sock_do_ioctl+0x3d/0xe0 [408508.143652] sock_ioctl+0x10e/0x330 [408508.144091] ? find_held_lock+0x2b/0x80 [408508.144537] __x64_sys_ioctl+0x96/0xe0 [408508.144979] do_syscall_64+0x79/0x3d0 [408508.145415] entry_SYSCALL_64_after_hwframe+0x76/0x7e [408508.145860] RIP: 0033:0x7f3e0bb4caff
How severe is CVE-2026-22981?
CVE-2026-22981 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-22981 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (2nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-22981?
CVE-2026-22981 primarily affects Linux Linux Kernel. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-22981?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-22981 have an EU (EUVD) identifier?
Yes. CVE-2026-22981 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-4317.
When was CVE-2026-22981 published?
CVE-2026-22981 was published on 2026-01-23 and last updated on 2026-06-17.

References

Affected products (5)

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