CVE-2026-89847 PUBLISHED

scsi: qla2xxx: Avoid double completion in async IOCB timeout

Assigner: Linux
Reserved: 11.09.2026 Published: 16.09.2026 Updated: 16.09.2026

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().

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS Score: 9.8

AV:N - qla2x00_async_iocb_timeout() runs on fabric login, CT/SNS, and target-mode NACK IOCBs; a remote FC/FCoE/FCIP peer delays then completes those exchanges so the response ISR races the timer. That is a SAN-network path, consistent with other qla2xxx FC-peer memory-corruption scores. AC:L - The peer controls both sides of the race by withholding the login/CT/NACK completion until the async timer fires, then posting it so the ISR removes the SRB while timeout still calls sp->done(). Abort failure is also attacker-driven via GFP_ATOMIC SRB exhaustion or ISP-abort from injected link errors. PR:N - Fabric login, name-server CT, and target-mode notify-ack run in driver ISR/DPC context with no Linux credential or capability check. FC-SP/EDIF is opt-in and rare, so a fabric peer needs no account on the victim host. UI:N - Discovery, PLOGI, and NACK IOCBs are posted automatically on link-up, RSCN, and inbound ELS. The async timer and response ISR then run without any victim mount, open, or administrator action. S:U - Double completion corrupts host-kernel SRB and completion state inside the qla2xxx driver. The impact stays in that kernel authority and is not a VM escape, IOMMU bypass, or other cross-boundary breakout. C:H - The extra sp->done() drops the SRB INIT kref twice so the timeout path later frees a mempool SRB still in use, a use-after-free that can disclose reused heap contents. The CTRL_VP path also complete()s a reclaimed on-stack completion. I:H - The same mempool SRB use-after-free and complete() write into a freed stack frame are kernel write primitives. Reuse of the freed SRB can hijack control flow rather than producing only a clean timeout. A:H - Double completion of a live SRB is a use-after-free that oopses or panics the host, as in the original switch-CT crash in qla2x00_chk_ms_status from the response ISR, taking down storage on the adapter.

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from f6145e86d21fccd59bbb87bc1e1eb076658fd79a to 71a7b6e3c7f121439f51a058e53d4a8e05b63dec (excl.)
  • affected from f6145e86d21fccd59bbb87bc1e1eb076658fd79a to 7257b5e1fb6c9387714f66e01b79ec82b717eede (excl.)
  • affected from f6145e86d21fccd59bbb87bc1e1eb076658fd79a to f5b660e0b0d9190d8853c795c2522cc5f8c93003 (excl.)
  • affected from f6145e86d21fccd59bbb87bc1e1eb076658fd79a to 6e217a9482eabbd8b29847be334c74cf468d3544 (excl.)
  • affected from f6145e86d21fccd59bbb87bc1e1eb076658fd79a to d6d856c722f40f0694ff755208552e658db6dd42 (excl.)
  • affected from f6145e86d21fccd59bbb87bc1e1eb076658fd79a to 9fa1d71233a82416492d9c9de9756ebe140fe714 (excl.)
  • affected from f6145e86d21fccd59bbb87bc1e1eb076658fd79a to 845d4abd92cd2f97551356c8b281ad6e197acb07 (excl.)
  • affected from f6145e86d21fccd59bbb87bc1e1eb076658fd79a to bb45bc4bd53c95a7bf6f782577b5ede94c0f8aa8 (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 4.19 is affected
  • unaffected from 0 to 4.19 (excl.)
  • unaffected from 5.10.270 to 5.10.* (incl.)
  • unaffected from 5.15.221 to 5.15.* (incl.)
  • unaffected from 6.1.188 to 6.1.* (incl.)
  • unaffected from 6.6.157 to 6.6.* (incl.)
  • unaffected from 6.12.110 to 6.12.* (incl.)
  • unaffected from 6.18.51 to 6.18.* (incl.)
  • unaffected from 7.2.5 to 7.2.* (incl.)
  • unaffected from 7.3-rc1 to * (incl.)

References