From 82808b422617ea5d1e62f5c5741eb8ce9dff4a7b Mon Sep 17 00:00:00 2001 From: Laszlo Ersek Date: Mon, 15 Jun 2020 16:45:14 +0200 Subject: [PATCH] Revert "OvmfPkg: use generic QEMU image loader for secure boot enabled ..." MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Cc: Jordan Justen Cc: Philippe Mathieu-Daudé Signed-off-by: Laszlo Ersek Acked-by: Ard Biesheuvel Message-Id: <20200615144514.24597-1-lersek@redhat.com> Reviewed-by: Philippe Mathieu-Daudé [lersek@redhat.com: truncate the subject line, originally auto-generated by git-revert, to pacify PatchCheck.py] --- 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 d0df9cbbfb..16103d1773 100644 --- a/OvmfPkg/OvmfPkgIa32.dsc +++ b/OvmfPkg/OvmfPkgIa32.dsc @@ -379,11 +379,7 @@ 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 b3ae62fee9..9597ef6721 100644 --- a/OvmfPkg/OvmfPkgIa32X64.dsc +++ b/OvmfPkg/OvmfPkgIa32X64.dsc @@ -383,11 +383,7 @@ 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 f7fe75ebf5..a6e585c03d 100644 --- a/OvmfPkg/OvmfPkgX64.dsc +++ b/OvmfPkg/OvmfPkgX64.dsc @@ -383,11 +383,7 @@ 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