Linux Kernel INVLPGB Flag Misconfiguration Vulnerability on AMD Zen2 Processors

A vulnerability exists in the Linux kernel's handling of the INVLPGB instruction for certain AMD Zen2 processors, specifically the Cyan Skillfish model. This issue arises from a misconfigured CPUID that incorrectly reports the INVLPGB bit, leading to system crashes when TLB flushes are performed using this instruction. The kernel's representation of the INVLPGB flag has been corrected to prevent confusion.

Impact

The vulnerability causes system crashes and panics due to improper handling of the INVLPGB instruction, which is used for TLB flush operations.

Remediation

Users can upgrade to the latest version of the Linux kernel where this vulnerability has been addressed. Instructions for downloading the patched version are available on the Linux Kernel Archive.