CVE-2021-47429

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description The issue is related to the powerpc/64s architecture in the Linux kernel. The machine check handler is not considered an NMI on 64s, and the early handler schedules the machine check exception handler to run when interrupts are enabled. However, in the case of an unrecoverable MCE, the true NMI is taken when MSR[RI] is clear, and it calls machine check exception directly. This can result in irq state and other things getting corrupted, triggering a BUG at arch/powerpc/include/asm/interrupt.h:168. The fix involves making an async version of the handler for normal cases and a NMI version for unrecoverable interrupts.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.