CVE-2021-47429

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Source
https://nvd.nist.gov/vuln/detail/CVE-2021-47429
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-47429.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2021-47429
Related
Published
2024-05-21T15:15:28Z
Modified
2024-09-18T01:00:21Z
Summary
[none]
Details

In the Linux kernel, the following vulnerability has been resolved:

powerpc/64s: Fix unrecoverable MCE calling async handler from NMI

The machine check handler is not considered NMI on 64s. The early handler is the true NMI handler, and then it schedules the machinecheckexception handler to run when interrupts are enabled.

This works fine except the case of an unrecoverable MCE, where the true NMI is taken when MSR[RI] is clear, it can not recover, so it calls machinecheckexception directly so something might be done about it.

Calling an async handler from NMI context can result in irq state and other things getting corrupted. This can also trigger the BUG at arch/powerpc/include/asm/interrupt.h:168 BUGON(!archirqdisabledregs(regs) && !(regs->msr & MSR_EE));

Fix this by making an _async version of the handler which is called in the normal case, and a NMI version that is called for unrecoverable interrupts.

References

Affected packages

Debian:12 / linux

Package

Name
linux
Purl
pkg:deb/debian/linux?arch=source

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
5.14.12-1

Ecosystem specific

{
    "urgency": "not yet assigned"
}

Debian:13 / linux

Package

Name
linux
Purl
pkg:deb/debian/linux?arch=source

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
5.14.12-1

Ecosystem specific

{
    "urgency": "not yet assigned"
}