CVE-2026-89854

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

scsi: qla2xxx: Fix cs84xx use-after-free on host teardown

qla84xx_put_chip() drops the last reference to ha->cs84xx and frees it via

__qla84xx_chip_release() without clearing ha->cs84xx. During teardown it ran

before scsi_remove_host(), which is what removes the 84xx_fw_version host

sysfs attribute. A concurrent read of that attribute in the window between

the two calls executes qla24xx_84xx_fw_version_show(), which dereferences

the freed ha->cs84xx, resulting in a use-after-free.

Move qla84xx_put_chip() to after scsi_remove_host() in both

qla2x00_remove_one() and qla2x00_disable_board_on_pci_error(). Once

scsi_remove_host() returns, the sysfs attribute is gone and kernfs has

drained any in-flight show(), so no reader can touch cs84xx; the put still

runs before the host and ha are freed.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References