Oracle Linux: CVE-2024-56568: ELSA-2025-20095: Unbreakable Enterprise kernel security update (IMPORTANT) (Multiple Advisories)

Oracle Linux: CVE-2024-56568: ELSA-2025-20095: Unbreakable Enterprise kernel security update (IMPORTANT) (Multiple Advisories)

Severity

5

CVSS

(AV:L/AC:L/Au:S/C:N/I:N/A:C)

Published

12/27/2024

Created

02/13/2025

Added

02/11/2025

Modified

02/13/2025

Description

In the Linux kernel, the following vulnerability has been resolved: iommu/arm-smmu: Defer probe of clients after smmu device bound Null pointer dereference occurs due to a race between smmu driver probe and client driver probe, when of_dma_configure() for client is called after the iommu_device_register() for smmu driver probe has executed but before the driver_bound() for smmu driver has been called. Following is how the race occurs: T1:Smmu device probeT2: Client device probe really_probe() arm_smmu_device_probe() iommu_device_register() really_probe() platform_dma_configure() of_dma_configure() of_dma_configure_id() of_iommu_configure() iommu_probe_device() iommu_init_device() arm_smmu_probe_device() arm_smmu_get_by_fwnode() driver_find_device_by_fwnode() driver_find_device() next_device() klist_next() /* null ptr assigned to smmu */ /* null ptr dereference while smmu->streamid_mask */ driver_bound() klist_add_tail() When this null smmu pointer is dereferenced later in arm_smmu_probe_device, the device crashes. Fix this by deferring the probe of the client device until the smmu device has bound to the arm smmu driver. [will: Add comment]

Solution(s)

• oracle-linux-upgrade-kernel-uek

References

• https://attackerkb.com/topics/cve-2024-56568
• CVE - 2024-56568
• ELSA-2025-20095