KVM: SEV: Use READ_ONCE() when reading entries/indices from PSC buffer
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 6.12.93, 6.18.35, 7.0.12
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: total
Summary
In the Linux kernel, the following vulnerability has been resolved: KVM: SEV: Use READ_ONCE() when reading entries/indices from PSC buffer Use READ_ONCE() when reading entries/indices from the guest-accessible Page State Change buffer to defend against TOCTOU bugs. Don't bother with READ_ONCE()/WRITE_ONCE() for cases where KVM is writing (and not consuming the result!), as the guest isn't supposed to touch the buffer while it's being processed. I.e. using READ_ONCE() is all about protecting against misbehaving guests.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: total
- Record last updated
Affected versions
- Linux Linux
From 9b54e248d2644be71cb394eb85f31ad99e023a05 · fixed in bd232801ef1d1fd985d2d4ca3cd1d888303ca86f; From 9b54e248d2644be71cb394eb85f31ad99e023a05 · fixed in b1dfaa6f7a957726a6800135be3659fbe4bbf2a4; From 9b54e248d2644be71cb394eb85f31ad99e023a05 · fixed in edbbe88f83b524434974e84808d3093199d67c24; From 9b54e248d2644be71cb394eb85f31ad99e023a05 · fixed in c8cc238093ca6c99267032f6cfe78f59389f3157
- Linux Linux
6.11
- KernelLinux
From 6.11.0 · fixed in 6.12.93; From 6.13.0 · fixed in 6.18.35; From 6.19.0 · fixed in 7.0.12