KernelScan.io

CRITICAL Introduced in 4.19

qla2xxx AsyncIOCB UAF

CVE-2026-89847

CVSS 9.8 / 10.0 NVD

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

KernelScan AI7.0HIGH

01

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().

02

Engine v0.6.0

Risk summary

A race condition in the QLogic Fibre Channel driver's async IOCB timeout handler can cause a use-after-free when the response interrupt handler completes a command before the timeout handler. This affects systems with QLogic FC hardware and can lead to kernel memory corruption, potentially allowing privilege escalation or denial of service. Exploitation requires winning a narrow timing window between ISR completion and timer expiry.

Affecteddrivers/scsi/qla2xxx/qla_init.c (qla2xxx SCSI driver)

Vulnerability analysis

The async IOCB timeout handler in the QLogic Fibre Channel driver unconditionally completes a command even when the response interrupt handler has already removed and completed that same command. When both paths run concurrently, the second completion call writes into a stack frame that the submitting function has already returned from and reclaimed, corrupting freed memory. The fix tracks whether the timeout path actually removed the command from the outstanding command list and only calls the completion callback if it did, ensuring each command is completed exactly once by whichever path owns it. This race is reachable on systems with QLogic Fibre Channel hardware where a local user can trigger fabric operations that lead to async IOCB timeouts, and requires winning a timing window between interrupt-driven completion and timer expiry.

03

BranchIntroducedFixed inPatch commit
5.104.195.10.27071a7b6e3c7f1
5.154.195.15.2217257b5e1fb6c
6.64.196.6.1576e217a9482ea
6.184.196.18.519fa1d71233a8
mainline4.197.3-rc1bb45bc4bd53c
7.24.197.2.5845d4abd92cd
6.124.196.12.110d6d856c722f4
6.14.196.1.188f5b660e0b0d9
cip/6.124.196.12.111-cip32d6d856c722f4