CVE-2025-21913: x86/amd_nb: Use rdmsr_safe() in amd_get_mmconfig_range()
In the Linux kernel, the following vulnerability has been resolved:
x86/amdnb: Use rdmsrsafe() in amdgetmmconfigrange()
Xen doesn't offer MSRFAM10HMMIOCONFBASE to all guests. This results in the following warning:
unchecked MSR access error: RDMSR from 0xc0010058 at rIP: 0xffffffff8101d19f (xendoreadmsr+0x7f/0xa0) Call Trace: xenreadmsr+0x1e/0x30 amdgetmmconfigrange+0x2b/0x80 quirkamdmmconfigarea+0x28/0x100 pnpfixupdevice+0x39/0x50 pnpadddevice+0xf/0x150 pnpadddevice+0x3d/0x100 pnpacpiadddevicehandler+0x1f9/0x280 acpinsgetdevicecallback+0x104/0x1c0 acpinswalknamespace+0x1d0/0x260 acpigetdevices+0x8a/0xb0 pnpacpiinit+0x50/0x80 dooneinitcall+0x46/0x2e0 kernelinitfreeable+0x1da/0x2f0 kernelinit+0x16/0x1b0 retfromfork+0x30/0x50 retfromforkasm+0x1b/0x30
based on quirks for a "PNP0c01" device. Treating MMCFG as disabled is the right course of action, so no change is needed there.
This was most likely exposed by fixing the Xen MSR accessors to not be silently-safe.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2025-21913?
CVE-2025-21913 has been classified with moderate severity due to the potential for unchecked MSR access.
How does CVE-2025-21913 affect the Linux kernel?
CVE-2025-21913 affects the Linux kernel by allowing unchecked RDMSR access, impacting system stability and security.
How do I fix CVE-2025-21913?
To fix CVE-2025-21913, update your Linux kernel to the latest stable version that includes the patch for this vulnerability.
What systems are impacted by CVE-2025-21913?
CVE-2025-21913 primarily impacts systems running the Linux kernel with AMD processors.
Is there a workaround for CVE-2025-21913 if I cannot update?
Currently, there is no known workaround for CVE-2025-21913; updating the kernel is the recommended mitigation.