[PATCH] tpm: do handle area size validation only when TPM space used

From: Jarkko Sakkinen
Date: Sun Mar 26 2017 - 17:08:35 EST


In order to not cause backwards compatibility issues with
/dev/tpm0 disable handle area size validation if tpm_transmit
is not called with a TPM space.

Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxx>
---
drivers/char/tpm/tpm-interface.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index bf0c3fa..158c1db 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -328,7 +328,9 @@ unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
}
EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);

-static bool tpm_validate_command(struct tpm_chip *chip, const u8 *cmd,
+static bool tpm_validate_command(struct tpm_chip *chip,
+ struct tpm_space *space,
+ const u8 *cmd,
size_t len)
{
const struct tpm_input_header *header = (const void *)cmd;
@@ -340,6 +342,9 @@ static bool tpm_validate_command(struct tpm_chip *chip, const u8 *cmd,
if (len < TPM_HEADER_SIZE)
return false;

+ if (!space)
+ return true;
+
if (chip->flags & TPM_CHIP_FLAG_TPM2 && chip->nr_commands) {
cc = be32_to_cpu(header->ordinal);

@@ -386,7 +391,7 @@ ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space,
unsigned long stop;
bool need_locality;

- if (!tpm_validate_command(chip, buf, bufsiz))
+ if (!tpm_validate_command(chip, space, buf, bufsiz))
return -EINVAL;

if (bufsiz > TPM_BUFSIZE)
--
2.9.3