Securing Linux VM boot with AMD SEV measurement
summary
Extends AMD SEV launch measurement by placing a hash table in initial guest memory (SHA‑256, 32‑byte hashes) that lists kernel, initrd and kernel command line digests so OVMF verifies any firmware config–loaded content before jumping to the kernel. Implementation adds qemu computing the hashes and populating the measured page and OVMF verification; edk2 merge occurred July 2021 and qemu inclusion targets version 62. Mitigates host-on-hostile-kernel swap; caveat: kernel/initrd/cmdline remain host‑readable. qemu+OVMF implementation merged into edk2 (July 2021)
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chapters (15)
- 0:00Intro
- 0:21Work of many people
- 0:45Confidential Computing setting
- 1:38The problem
- 2:05AMD SEV
- 3:27VM boot process with -kernel
- 5:48Host attack on boot with -kernel
- 7:09Vulnerability
- 8:14Hashes GUIDed table
- 9:50Solution details
- 10:54Attack mitigation
- 12:15Caveat
- 13:05Implementation status
- 14:39Accessing injected secrets
- 17:06Future plans
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