From: Hans de Goede <[email protected]> Commit 79832f0b5f71 ("efi/libstub/tpm: Initialize pointer variables to zero for mixed mode") fixes a problem with the tpm code on mixed mode (64 bit kernel on 32 bit UEFI), where 64-bit pointer variables are not fully initialized by the 32-bit EFI code.
A similar problem applies to the efi_physical_addr_t variables which are written by the get_event_log EFI call. Even though efi_physical_addr_t is 64 bit everywhere it seems that some 32 bit UEFI implementations only fill in the lower 32 bits when passed a pointer to an efi_physical_addr_t to fill. This commit initializes these to 0 to, to ensure the upper 32 bits are 0 in mixed mode. This fixes recent kernels sometimes hanging during early boot on mixed mode UEFI systems. Cc: <[email protected]> # v4.16+ Signed-off-by: Hans de Goede <[email protected]> Signed-off-by: Ard Biesheuvel <[email protected]> --- drivers/firmware/efi/libstub/tpm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/firmware/efi/libstub/tpm.c b/drivers/firmware/efi/libstub/tpm.c index caa37a6dd9d4..a90b0b8fc69a 100644 --- a/drivers/firmware/efi/libstub/tpm.c +++ b/drivers/firmware/efi/libstub/tpm.c @@ -64,7 +64,7 @@ static void efi_retrieve_tpm2_eventlog_1_2(efi_system_table_t *sys_table_arg) efi_guid_t tcg2_guid = EFI_TCG2_PROTOCOL_GUID; efi_guid_t linux_eventlog_guid = LINUX_EFI_TPM_EVENT_LOG_GUID; efi_status_t status; - efi_physical_addr_t log_location, log_last_entry; + efi_physical_addr_t log_location = 0, log_last_entry = 0; struct linux_efi_tpm_eventlog *log_tbl = NULL; unsigned long first_entry_addr, last_entry_addr; size_t log_size, last_entry_size; -- 2.17.1 -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
