CVE-2024-56764: ublk: detach gendisk from ublk device if add_disk() fails

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-01-06 · updated 2026-06-17
Weakness: CWE-416

Description

In the Linux kernel, the following vulnerability has been resolved: ublk: detach gendisk from ublk device if add_disk() fails Inside ublk_abort_requests(), gendisk is grabbed for aborting all inflight requests. And ublk_abort_requests() is called when exiting the uring context or handling timeout. If add_disk() fails, the gendisk may have been freed when calling ublk_abort_requests(), so use-after-free can be caused when getting disk's reference in ublk_abort_requests(). Fixes the bug by detaching gendisk from ublk device if add_disk() fails.

Affected products

Linux kernel: from 6.7 before 6.12.8; 6.13-rc1, 6.13-rc2, 6.13-rc3, 6.13-rc4 — fixed in 6.12.8

How to fix

Upgrade to a fixed version: Linux kernel 6.12.8. Check the vendor advisory for mitigations.

References

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