From a8dbb565f7ef8722d26712c8c14512b8f21e7734 Mon Sep 17 00:00:00 2001
From: Michal Suchanek <msuchanek@suse.de>
Date: Wed, 7 Jul 2021 12:48:32 +0200
Subject: [PATCH] efi/tpm: Differentiate missing and invalid final event log
table.
To: linux-integrity@vger.kernel.org, Ard Biesheuvel <ardb@kernel.org>
Cc: Peter Huewe <peterhuewe@gmx.de>, Jarkko Sakkinen <jarkko@kernel.org>, Jason Gunthorpe <jgg@ziepe.ca>, Loïc Yhuel <loic.yhuel@gmail.com>, Javier Martinez Canillas <javierm@redhat.com>, Jerry Snitselaar <jsnitsel@redhat.com>, Matthew Garrett <mjg59@google.com>,
Cc: Ard Biesheuvel <ardb@kernel.org>,Jerry Snitselaar <jsnitsel@redhat.com>,"Loïc Yhuel" <loic.yhuel@gmail.com>,Javier Martinez Canillas <javierm@redhat.com>,Matthew Garrett <mjg59@google.com>,linux-efi@vger.kernel.org,linux-kernel@vger.kernel.org,
References: bsc#1188036
Patch-mainline: v5.14-rc3
Git-commit: 674a9f1f6815849bfb5bf385e7da8fc198aaaba9
Missing TPM final event log table is not a firmware bug.
Clearly if providing event log in the old format makes the final event
log invalid it should not be provided at least in that case.
Fixes: b4f1874c6216 ("tpm: check event log version before reading final events")
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
---
drivers/firmware/efi/tpm.c | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/drivers/firmware/efi/tpm.c b/drivers/firmware/efi/tpm.c
index c1955d320fec..8f665678e9e3 100644
--- a/drivers/firmware/efi/tpm.c
+++ b/drivers/firmware/efi/tpm.c
@@ -62,9 +62,11 @@ int __init efi_tpm_eventlog_init(void)
tbl_size = sizeof(*log_tbl) + log_tbl->size;
memblock_reserve(efi.tpm_log, tbl_size);
- if (efi.tpm_final_log == EFI_INVALID_TABLE_ADDR ||
- log_tbl->version != EFI_TCG2_EVENT_LOG_FORMAT_TCG_2) {
- pr_warn(FW_BUG "TPM Final Events table missing or invalid\n");
+ if (efi.tpm_final_log == EFI_INVALID_TABLE_ADDR) {
+ pr_info("TPM Final Events table not present\n");
+ goto out;
+ } else if (log_tbl->version != EFI_TCG2_EVENT_LOG_FORMAT_TCG_2) {
+ pr_warn(FW_BUG "TPM Final Events table invalid\n");
goto out;
}
--
2.26.2