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

[Jarkko Sakkinen]

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.sakki...@iki.fi>
---
 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