diff options
| author | Ard Biesheuvel <ard.biesheuvel@linaro.org> | 2018-03-13 17:09:21 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2018-03-13 17:28:29 +0300 |
| commit | 79832f0b5f718e0023d9dd73e6845310609a564d (patch) | |
| tree | 676d06e2e0b97673702dcc7ac8e5a0bfd41028c5 | |
| parent | fc6eabbbf8ef99efed778dd5afabc83c21dba585 (diff) | |
| download | linux-79832f0b5f718e0023d9dd73e6845310609a564d.tar.xz | |
efi/libstub/tpm: Initialize pointer variables to zero for mixed mode
As reported by Jeremy Cline, running the new TPM libstub code in mixed
mode (i.e., 64-bit kernel on 32-bit UEFI) results in hangs when invoking
the TCG2 protocol, or when accessing the log_tbl pool allocation.
The reason turns out to be that in both cases, the 64-bit pointer
variables are not fully initialized by the 32-bit EFI code, and so
we should take care to zero initialize these variables beforehand,
or we'll end up dereferencing bogus pointers.
Reported-by: Jeremy Cline <jeremy@jcline.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hdegoede@redhat.com
Cc: jarkko.sakkinen@linux.intel.com
Cc: javierm@redhat.com
Cc: linux-efi@vger.kernel.org
Cc: tweek@google.com
Link: http://lkml.kernel.org/r/20180313140922.17266-2-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
| -rw-r--r-- | drivers/firmware/efi/libstub/tpm.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/firmware/efi/libstub/tpm.c b/drivers/firmware/efi/libstub/tpm.c index da661bf8cb96..13c1edd37e96 100644 --- a/drivers/firmware/efi/libstub/tpm.c +++ b/drivers/firmware/efi/libstub/tpm.c @@ -68,11 +68,11 @@ void efi_retrieve_tpm2_eventlog_1_2(efi_system_table_t *sys_table_arg) 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; - struct linux_efi_tpm_eventlog *log_tbl; + struct linux_efi_tpm_eventlog *log_tbl = NULL; unsigned long first_entry_addr, last_entry_addr; size_t log_size, last_entry_size; efi_bool_t truncated; - void *tcg2_protocol; + void *tcg2_protocol = NULL; status = efi_call_early(locate_protocol, &tcg2_guid, NULL, &tcg2_protocol); |