On 06/15/20 16:49, Philippe Mathieu-Daudé wrote:
> On 6/15/20 4:45 PM, Laszlo Ersek wrote:
>> This reverts commit ced77332cab626f35fbdb36630be27303d289d79.
>>
>> The command
>>
>> virt-install --location NETWORK-URL
>>
>> downloads the vmlinuz and initrd files from the remote OS tree, and passes
>> them to the guest firmware via fw_cfg.
>>
>> When used with IA32 / X64 guests, virt-install expects the guest firmware
>> to do two things, at the same time:
>>
>> - launch the fw_cfg kernel image even if the latter does not pass SB
>> verification (SB checking is supposed to be bypassed entirely in favor
>> of the Linux/x86 Boot Protocol),
>>
>> - still let the guest kernel perceive SB as enabled.
>>
>> Commit ced77332cab6 prevented this, by removing the Linux/x86 Boot
>> Protocol from such an OVMF image that was built with SECURE_BOOT_ENALBE.
>> While that's the right thing in theory, in practice "virt-install
>> --location NETWORK-URL" is entrenched, and we shouldn't break it.
>>
>> We can tolerate the Linux/x86 Boot Protocol as a one-of-a-kind SB bypass
>> for direct-booted kernels, because:
>>
>> - the fw_cfg content comes from QEMU, and the guest is already at QEMU's
>> mercy,
>>
>> - in the guest, OS boots after the initial installation will use "shim"
>> rather than an fw_cfg kernel, which we can consider somewhat similar to
>> "Audit Mode / Deployed Mode" (~ trust for install, lock down after).
>>
>> Cc: Ard Biesheuvel <ard.biesheu...@arm.com>
>> Cc: Jordan Justen <jordan.l.jus...@intel.com>
>> Cc: Philippe Mathieu-Daudé <phi...@redhat.com>
>> Signed-off-by: Laszlo Ersek <ler...@redhat.com>
>> Acked-by: Ard Biesheuvel <ard.biesheu...@arm.com>
>> ---
>>
>> Notes:
>> - pick up Ard's ACK from
>>
>>
>> c06ee730-e421-0aa5-882f-bc09ae9c546f@arm.com">http://mid.mail-archive.com/c06ee730-e421-0aa5-882f-bc09ae9c546f@arm.com
>> https://edk2.groups.io/g/devel/message/61169
>>
>> - posting to the list to enable feedback on the commit message (I intend
>> to push the patch in one or two days)
>>
>> - repo: https://pagure.io/lersek/edk2.git
>> branch: reenable_fwcfg_x86_boot_proto
>>
>> OvmfPkg/OvmfPkgIa32.dsc | 4 ----
>> OvmfPkg/OvmfPkgIa32X64.dsc | 4 ----
>> OvmfPkg/OvmfPkgX64.dsc | 4 ----
>> 3 files changed, 12 deletions(-)
>>
>> diff --git a/OvmfPkg/OvmfPkgIa32.dsc b/OvmfPkg/OvmfPkgIa32.dsc
>> index d0df9cbbfb2b..16103d177374 100644
>> --- a/OvmfPkg/OvmfPkgIa32.dsc
>> +++ b/OvmfPkg/OvmfPkgIa32.dsc
>> @@ -379,11 +379,7 @@ [LibraryClasses.common.DXE_DRIVER]
>> PciLib|OvmfPkg/Library/DxePciLibI440FxQ35/DxePciLibI440FxQ35.inf
>> MpInitLib|UefiCpuPkg/Library/MpInitLib/DxeMpInitLib.inf
>> QemuFwCfgS3Lib|OvmfPkg/Library/QemuFwCfgS3Lib/DxeQemuFwCfgS3LibFwCfg.inf
>> -!if $(SECURE_BOOT_ENABLE) == TRUE
>> -
>> QemuLoadImageLib|OvmfPkg/Library/GenericQemuLoadImageLib/GenericQemuLoadImageLib.inf
>> -!else
>>
>> QemuLoadImageLib|OvmfPkg/Library/X86QemuLoadImageLib/X86QemuLoadImageLib.inf
>> -!endif
>> !if $(TPM_ENABLE) == TRUE
>> Tpm12DeviceLib|SecurityPkg/Library/Tpm12DeviceLibTcg/Tpm12DeviceLibTcg.inf
>> Tpm2DeviceLib|SecurityPkg/Library/Tpm2DeviceLibTcg2/Tpm2DeviceLibTcg2.inf
>> diff --git a/OvmfPkg/OvmfPkgIa32X64.dsc b/OvmfPkg/OvmfPkgIa32X64.dsc
>> index b3ae62fee92b..9597ef6721da 100644
>> --- a/OvmfPkg/OvmfPkgIa32X64.dsc
>> +++ b/OvmfPkg/OvmfPkgIa32X64.dsc
>> @@ -383,11 +383,7 @@ [LibraryClasses.common.DXE_DRIVER]
>> PciLib|OvmfPkg/Library/DxePciLibI440FxQ35/DxePciLibI440FxQ35.inf
>> MpInitLib|UefiCpuPkg/Library/MpInitLib/DxeMpInitLib.inf
>> QemuFwCfgS3Lib|OvmfPkg/Library/QemuFwCfgS3Lib/DxeQemuFwCfgS3LibFwCfg.inf
>> -!if $(SECURE_BOOT_ENABLE) == TRUE
>> -
>> QemuLoadImageLib|OvmfPkg/Library/GenericQemuLoadImageLib/GenericQemuLoadImageLib.inf
>> -!else
>>
>> QemuLoadImageLib|OvmfPkg/Library/X86QemuLoadImageLib/X86QemuLoadImageLib.inf
>> -!endif
>> !if $(TPM_ENABLE) == TRUE
>> Tpm12DeviceLib|SecurityPkg/Library/Tpm12DeviceLibTcg/Tpm12DeviceLibTcg.inf
>> Tpm2DeviceLib|SecurityPkg/Library/Tpm2DeviceLibTcg2/Tpm2DeviceLibTcg2.inf
>> diff --git a/OvmfPkg/OvmfPkgX64.dsc b/OvmfPkg/OvmfPkgX64.dsc
>> index f7fe75ebf531..a6e585c03d41 100644
>> --- a/OvmfPkg/OvmfPkgX64.dsc
>> +++ b/OvmfPkg/OvmfPkgX64.dsc
>> @@ -383,11 +383,7 @@ [LibraryClasses.common.DXE_DRIVER]
>> PciLib|OvmfPkg/Library/DxePciLibI440FxQ35/DxePciLibI440FxQ35.inf
>> MpInitLib|UefiCpuPkg/Library/MpInitLib/DxeMpInitLib.inf
>> QemuFwCfgS3Lib|OvmfPkg/Library/QemuFwCfgS3Lib/DxeQemuFwCfgS3LibFwCfg.inf
>> -!if $(SECURE_BOOT_ENABLE) == TRUE
>> -
>> QemuLoadImageLib|OvmfPkg/Library/GenericQemuLoadImageLib/GenericQemuLoadImageLib.inf
>> -!else
>>
>> QemuLoadImageLib|OvmfPkg/Library/X86QemuLoadImageLib/X86QemuLoadImageLib.inf
>> -!endif
>> !if $(TPM_ENABLE) == TRUE
>> Tpm12DeviceLib|SecurityPkg/Library/Tpm12DeviceLibTcg/Tpm12DeviceLibTcg.inf
>> Tpm2DeviceLib|SecurityPkg/Library/Tpm2DeviceLibTcg2/Tpm2DeviceLibTcg2.inf
>>
>
> Reviewed-by: Philippe Mathieu-Daude <phi...@redhat.com>
Thanks!
Merged as commit 82808b422617 ('Revert "OvmfPkg: use generic QEMU image
loader for secure boot enabled ..."', 2020-06-16) via
<https://github.com/tianocore/edk2/pull/703>, after truncating the
subject line (originally auto-generated by git-revert), to pacify
PatchCheck.py.
Laszlo
-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#61358): https://edk2.groups.io/g/devel/message/61358
Mute This Topic: https://groups.io/mt/74895863/21656
Group Owner: devel+ow...@edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com]
-=-=-=-=-=-=-=-=-=-=-=-
