Description

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.

References 4

• git.kernel.org https://git.kernel.org/stable/c/6615212d8e131b45bd9705b0d69cc0d2f624666f
• git.kernel.org https://git.kernel.org/stable/c/8ae7457e71a320867d868f2622d7c643596e4f43
• git.kernel.org https://git.kernel.org/stable/c/ac3f9c9f1b37edaa7d1a9b908bc79d843955a1a2
• git.kernel.org https://git.kernel.org/stable/c/ba50e7773a99a109a1ea6f753b766a080d3b21cc

Remediation