Hi, In response to your queries:
1) With kernel version 5.0.0-37, I can confirm that the event log provided by the kernel is inconsistent with the TPM for PCR7 in a VM that's running OVMF. This is because of the opposite problem - in this case, the last event is missing from the log exported by the kernel. I'm not sure why that is yet because it occurs before ExitBootServices() and should appear in the firmware's main event log. There is also a mismatch for PCR5, but this one is expected because the kernel is missing events that occur as a result of or after ExitBootServices() (in this case, it misses 2 EV_EFI_ACTION events). This is the problem that will be addressed by this bug report. 2) The stock kernel for Ubuntu 18.04 doesn't export duplicate events in the event log because it doesn't contain any code to handle the final events table (to retrieve events that are recorded as a result of or after ExitBootServices()). The duplicate events occur in the test kernel with the patches in comment 12 applied because it misses some additional fixes to de-duplicate events that are recorded both to the firmware's main event log and the final events table. Events that occur between the first call to GetEventLog() and ExitBootServices() are recorded by the firmware to both places. 3) I think this is a GRUB issue. AFAICT, GRUB's linux loader only boots the kernel via its EFI stub when secure boot is enabled, and I think you need to boot the kernel with the EFI stub in order for it to retrieve the event log. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux-azure in Ubuntu. https://bugs.launchpad.net/bugs/1838796 Title: TPM event log does not contain events measured after ExitBootServices Status in linux package in Ubuntu: Won't Fix Status in linux-azure package in Ubuntu: In Progress Status in linux source package in Xenial: Won't Fix Status in linux-azure source package in Xenial: In Progress Status in linux source package in Disco: Won't Fix Status in linux-azure source package in Disco: In Progress Bug description: The TPM event log (/sys/kernel/security/tpm0/binary_bios_measurements) does not contain any events that are measured by UEFI after the kernel's EFI Boot stub calls ExitBootServices(). This means that PCR values calculated from the event log will not match the actual PCR values on the machine for PCR indices into which these events are measured. There are upstream patches to fix this in the mainline kernel tree: https://lore.kernel.org/lkml/20190520205501.177637-1-matthewgarr...@google.com/ --- ProblemType: Bug ApportVersion: 2.20.9-0ubuntu7.5 Architecture: amd64 AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1: CRDA: Error: command ['iw', 'reg', 'get'] failed with exit code 1: nl80211 not found. CurrentDesktop: ubuntu:GNOME DistroRelease: Ubuntu 18.04 InstallationDate: Installed on 2019-06-20 (43 days ago) InstallationMedia: Ubuntu-Server 18.04.2 LTS "Bionic Beaver" - Release amd64 (20190210) IwConfig: eth0 no wireless extensions. lo no wireless extensions. Lspci: Lsusb: Error: command ['lsusb'] failed with exit code 1: MachineType: Microsoft Corporation Virtual Machine Package: linux (not installed) ProcEnviron: TERM=xterm-256color PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=en_US.UTF-8 SHELL=/bin/bash ProcFB: 0 hyperv_fb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.18.0-22-generic root=UUID=fcb8dc9d-4dd3-490f-9f1c-fa6364770bb0 ro ProcVersionSignature: Ubuntu 4.18.0-22.23~18.04.1-generic 4.18.20 RelatedPackageVersions: linux-restricted-modules-4.18.0-22-generic N/A linux-backports-modules-4.18.0-22-generic N/A linux-firmware 1.173.3 RfKill: Tags: bionic Uname: Linux 4.18.0-22-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dip lpadmin lxd plugdev sambashare sudo _MarkForUpload: True dmi.bios.date: 01/30/2019 dmi.bios.vendor: Microsoft Corporation dmi.bios.version: Hyper-V UEFI Release v4.0 dmi.board.asset.tag: None dmi.board.name: Virtual Machine dmi.board.vendor: Microsoft Corporation dmi.board.version: Hyper-V UEFI Release v4.0 dmi.chassis.asset.tag: 8486-4870-7514-9524-5524-7794-69 dmi.chassis.type: 3 dmi.chassis.vendor: Microsoft Corporation dmi.chassis.version: Hyper-V UEFI Release v4.0 dmi.modalias: dmi:bvnMicrosoftCorporation:bvrHyper-VUEFIReleasev4.0:bd01/30/2019:svnMicrosoftCorporation:pnVirtualMachine:pvrHyper-VUEFIReleasev4.0:rvnMicrosoftCorporation:rnVirtualMachine:rvrHyper-VUEFIReleasev4.0:cvnMicrosoftCorporation:ct3:cvrHyper-VUEFIReleasev4.0: dmi.product.family: Virtual Machine dmi.product.name: Virtual Machine dmi.product.sku: None dmi.product.version: Hyper-V UEFI Release v4.0 dmi.sys.vendor: Microsoft Corporation To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1838796/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
