CVE-2026-74472

/// Technical description

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

ublk: reset kernel-owned dev_info fields in ublk_ctrl_add_dev()

ublk_ctrl_add_dev() memcpy()s the userspace ublksrv_ctrl_dev_info into

ub->dev_info and then fixes up the fields the driver owns, but misses

->state and ->ublksrv_pid.

A device added with ->state = UBLK_S_DEV_LIVE passes the

"->state != UBLK_S_DEV_DEAD" test that ublk_stop_dev_unlocked() uses as its

proxy for "a disk is attached", while ->ub_disk is still NULL, so DEL_DEV

right after ADD_DEV oopses in del_gendisk(). UBLK_S_DEV_QUIESCED plus

UBLK_F_USER_RECOVERY dies one step earlier, in ublk_force_abort_dev(). A

poisoned ->state also gets START_USER_RECOVERY and the char device

read/write path onto a device that was never started, and wedges START_DEV

at -EEXIST. A poisoned ->ublksrv_pid just makes GET_DEV_INFO report an

unrelated task as the ublk server.

Reset both after the memcpy(), as ublk_detach_disk() does. Userspace only

ever reads these bac

/// 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