CVE-2023-52455: iommu: Don't reserve 0-length IOVA region
In the Linux kernel, the following vulnerability has been resolved:
iommu: Don't reserve 0-length IOVA region
When the bootloader/firmware doesn't setup the framebuffers, their address and size are 0 in "iommu-addresses" property. If IOVA region is reserved with 0 length, then it ends up corrupting the IOVA rbtree with an entry which has pfnhi < pfnlo. If we intend to use display driver in kernel without framebuffer then it's causing the display IOMMU mappings to fail as entire valid IOVA space is reserved when address and length are passed as 0. An ideal solution would be firmware removing the "iommu-addresses" property and corresponding "memory-region" if display is not present. But the kernel should be able to handle this by checking for size of IOVA region and skipping the IOVA reservation if size is 0. Also, add a warning if firmware is requesting 0-length IOVA region reservation.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
debian/linuxto a version that resolves this vulnerability.Fixed in 5.10.223-1Fixed in 5.10.234-1Fixed in 6.1.129-1Fixed in 6.1.135-1Fixed in 6.12.22-1Fixed in 6.12.25-1 - Upgrade
Upgrade
redhat/kernelto a version that resolves this vulnerability.Fixed in 6.8 - Configuration
Remove the "iommu-addresses" property and its corresponding "memory-region" property when the display is not present.
Bootloader/firmware display configuration iommu-addresses and corresponding memory-region properties = removed when display is not present
Event History
Frequently Asked Questions
What is the severity of CVE-2023-52455?
CVE-2023-52455 is considered to have a high impact due to potential system instability resulting from IOVA region mismanagement.
How do I fix CVE-2023-52455?
To fix CVE-2023-52455, update the Linux kernel to version 6.8 or later, or apply the specified patches for earlier versions.
Which versions of the Linux kernel are affected by CVE-2023-52455?
CVE-2023-52455 affects Linux kernel versions between 6.3.0 and 6.7.2 and also includes specific older versions like 5.10.x and 6.1.x.
What are the potential risks of not addressing CVE-2023-52455?
Neglecting to address CVE-2023-52455 may lead to system crashes or unreliable hardware operations due to improper IOVA region allocations.
Who is responsible for releasing the patches for CVE-2023-52455?
Patches for CVE-2023-52455 have been released by maintainers of the Linux kernel across various distributions such as Red Hat and Debian.