2020-02-25 15:35:16

by Tom Lendacky

[permalink] [raw]
Subject: [PATCH] x86/efi: Add additional efi tables for unencrypted mapping checks

When booting with SME active, EFI tables must be mapped unencrypted since
they were built by UEFI in unencrypted memory. Update the list of tables
to be checked during early_memremap() processing to account for new EFI
tables.

This fixes a bug where an EFI TPM log table has been created by UEFI, but
it lives in memory that has been marked as usable rather than reserved.

Signed-off-by: Tom Lendacky <[email protected]>
---
arch/x86/platform/efi/efi.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index ae923ee8e2b4..eba5038c7a44 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -85,6 +85,9 @@ static const unsigned long * const efi_tables[] = {
#ifdef CONFIG_EFI_RCI2_TABLE
&rci2_table_phys,
#endif
+ &efi.rng_seed,
+ &efi.tpm_log,
+ &efi.tpm_final_log,
};

u64 efi_setup; /* efi setup_data physical address */
--
2.17.1


2020-02-25 16:13:57

by Ard Biesheuvel

[permalink] [raw]
Subject: Re: [PATCH] x86/efi: Add additional efi tables for unencrypted mapping checks

On Tue, 25 Feb 2020 at 16:34, Tom Lendacky <[email protected]> wrote:
>
> When booting with SME active, EFI tables must be mapped unencrypted since
> they were built by UEFI in unencrypted memory. Update the list of tables
> to be checked during early_memremap() processing to account for new EFI
> tables.
>
> This fixes a bug where an EFI TPM log table has been created by UEFI, but
> it lives in memory that has been marked as usable rather than reserved.
>
> Signed-off-by: Tom Lendacky <[email protected]>

Thanks Tom

Mind respinning this on top of efi/next?

https://git.kernel.org/pub/scm/linux/kernel/git/efi/efi.git/

Thanks,


> ---
> arch/x86/platform/efi/efi.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
> index ae923ee8e2b4..eba5038c7a44 100644
> --- a/arch/x86/platform/efi/efi.c
> +++ b/arch/x86/platform/efi/efi.c
> @@ -85,6 +85,9 @@ static const unsigned long * const efi_tables[] = {
> #ifdef CONFIG_EFI_RCI2_TABLE
> &rci2_table_phys,
> #endif
> + &efi.rng_seed,
> + &efi.tpm_log,
> + &efi.tpm_final_log,
> };
>
> u64 efi_setup; /* efi setup_data physical address */
> --
> 2.17.1
>

2020-02-25 17:56:05

by Tom Lendacky

[permalink] [raw]
Subject: Re: [PATCH] x86/efi: Add additional efi tables for unencrypted mapping checks

On 2/25/20 10:09 AM, Ard Biesheuvel wrote:
> On Tue, 25 Feb 2020 at 16:34, Tom Lendacky <[email protected]> wrote:
>>
>> When booting with SME active, EFI tables must be mapped unencrypted since
>> they were built by UEFI in unencrypted memory. Update the list of tables
>> to be checked during early_memremap() processing to account for new EFI
>> tables.
>>
>> This fixes a bug where an EFI TPM log table has been created by UEFI, but
>> it lives in memory that has been marked as usable rather than reserved.
>>
>> Signed-off-by: Tom Lendacky <[email protected]>
>
> Thanks Tom
>
> Mind respinning this on top of efi/next?

Sure, no problem, v2 on the way. I wasn't sure if this would go through
the x86 tree or the efi tree (though this should apply cleanly to efi/next
with just a few lines of offset).

Thanks,
Tom

>
> https://git.kernel.org/pub/scm/linux/kernel/git/efi/efi.git/>
> Thanks,
>
>
>> ---
>> arch/x86/platform/efi/efi.c | 3 +++
>> 1 file changed, 3 insertions(+)
>>
>> diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
>> index ae923ee8e2b4..eba5038c7a44 100644
>> --- a/arch/x86/platform/efi/efi.c
>> +++ b/arch/x86/platform/efi/efi.c
>> @@ -85,6 +85,9 @@ static const unsigned long * const efi_tables[] = {
>> #ifdef CONFIG_EFI_RCI2_TABLE
>> &rci2_table_phys,
>> #endif
>> + &efi.rng_seed,
>> + &efi.tpm_log,
>> + &efi.tpm_final_log,
>> };
>>
>> u64 efi_setup; /* efi setup_data physical address */
>> --
>> 2.17.1
>>