x86/sev: Make enc_dec_hypercall() accept a size instead of npages
In the Linux kernel, the following vulnerability has been resolved: x86/sev: Make enc_dec_hypercall() accept a size instead of npages enc_dec_hypercall() accepted a page count instead of a size, which forced its callers to round up. As a result, non-page aligned vaddrs caused pages to be spuriously marked as decrypted via the encryption status hypercall, which in turn caused consistent corruption of pages during live migration. Live migration requires accurate encryption status information to avoid migrating pages from the wrong perspective.
02 / AFFECTED SOFTWARE
Affected packages
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
In the Linux kernel, the following vulnerability has been resolved: x86/sev: Make enc_dec_hypercall() accept a size instead of npages enc_dec_hypercall() accepted a page count instead of a size, which forced its callers to round up. As a result, non-page aligned vaddrs caused pages to be spuriously marked as decrypted via the encryption status hypercall, which in turn caused consistent corruption of pages during live migration. Live migration requires accurate encryption status information to avoid migrating pages from the wrong perspective.
05 / REFERENCES
Further evidence
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- https://git.kernel.org/stable/c/6615212d8e131b45bd9705b0d69cc0d2f624666f
- https://git.kernel.org/stable/c/8ae7457e71a320867d868f2622d7c643596e4f43
- https://git.kernel.org/stable/c/ac3f9c9f1b37edaa7d1a9b908bc79d843955a1a2
- https://git.kernel.org/stable/c/ba50e7773a99a109a1ea6f753b766a080d3b21cc
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/53xxx/CVE-2023-53996.json
- https://nvd.nist.gov/vuln/detail/CVE-2023-53996