x86/sev: Evict cache lines during SNP memory validation
- 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- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean?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 6.1.148, 6.6.102, 6.12.42, 6.15.10, 6.16.1
- 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: x86/sev: Evict cache lines during SNP memory validation An SNP cache coherency vulnerability requires a cache line eviction mitigation when validating memory after a page state change to private. The specific mitigation is to touch the first and last byte of each 4K page that is being validated. There is no need to perform the mitigation when performing a page state change to shared and rescinding validation. CPUID bit Fn8000001F_EBX[31] defines the COHERENCY_SFW_NO CPUID bit that, when set, indicates that the software mitigation for this vulnerability is not needed. Implement the mitigation and invoke it when validating memory (making it private) and the COHERENCY_SFW_NO bit is not set, indicating the SNP guest is vulnerable.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: total
- Record last updated
Affected versions
- Linux Linux
From 4f9c403e44e5e88feb27d5e617d1adc9cc7ef684 · fixed in 1fec416c03d0a64cc21aa04ce4aa14254b017e6a; From 4f9c403e44e5e88feb27d5e617d1adc9cc7ef684 · fixed in 1fb873971e23c35c53823c62809a474a92bc3022; From 4f9c403e44e5e88feb27d5e617d1adc9cc7ef684 · fixed in aed15fc08f15dbb15822b2a0b653f67e76aa0fdf; From 4f9c403e44e5e88feb27d5e617d1adc9cc7ef684 · fixed in a762a4c8d9e768b538b3cc60615361a8cf377de8; From 4f9c403e44e5e88feb27d5e617d1adc9cc7ef684 · fixed in f92af52e6dbd8d066d77beba451e0230482dc45b; From 4f9c403e44e5e88feb27d5e617d1adc9cc7ef684 · fixed in 7b306dfa326f70114312b320d083b21fa9481e1e
- Linux Linux
5.19
- KernelLinux
From 5.19.0 · fixed in 6.1.148; From 6.2.0 · fixed in 6.6.102; From 6.7.0 · fixed in 6.12.42; From 6.13.0 · fixed in 6.15.10; From 6.16.0 · fixed in 6.16.1