CVE-2026-89854scsi: qla2xxx: Fix cs84xx use-after-free on host teardown

Official 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.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/8c1ebcade6aac58137f2645b579894301febabf3
• https://git.kernel.org/stable/c/1d8bbc4344b9367d9d54731475d745fbc9ea28f2
• https://git.kernel.org/stable/c/2c3b17ee53f034936f7398dbf4d143e608b7c35c
• https://git.kernel.org/stable/c/ae09260be7454ed7630a913f147591a25e3a9d09
• https://git.kernel.org/stable/c/fcf0804dfe05862007189ac9dc4dc2063be36de1
• https://git.kernel.org/stable/c/8286a9095fb59751fba171afa2b4f590271c87d5
• https://git.kernel.org/stable/c/122bf170c94a3797531b12fee580639a5dc893ed
• https://git.kernel.org/stable/c/33d102102d925357c5fd172dd6672a27d74b3215