tpm: add vendor flag to command code validation

Some TPM 2.0 devices have support for additional commands which are not
part of the TPM 2.0 specifications.
These commands are identified with bit 29 of the 32 bits command codes.
Contrarily to other fields of the TPMA_CC spec structure used to list
available commands, the Vendor flag also has to be present in the
command code itself (TPM_CC) when called.

Add this flag to tpm_find_cc() mask to prevent blocking vendor command
codes that can actually be supported by the underlying TPM device.

Signed-off-by: Julien Gomes <julien@arista.com>
Tested-by: Jarkko Sakkinen <jarkko@kernel.org>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>

diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 65d03867e114c563de61fbb6e06cbfe4505cfd99..93545be190a50d54fec136152d6ef23fa81e2be3 100644 (file)
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -777,10 +777,12 @@ out:
 
 int tpm2_find_cc(struct tpm_chip *chip, u32 cc)
 {
+       u32 cc_mask;
        int i;
 
+       cc_mask = 1 << TPM2_CC_ATTR_VENDOR | GENMASK(15, 0);
        for (i = 0; i < chip->nr_commands; i++)
-               if (cc == (chip->cc_attrs_tbl[i] & GENMASK(15, 0)))
+               if (cc == (chip->cc_attrs_tbl[i] & cc_mask))
                        return i;
 
        return -1;

diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index dfeb25a0362deee6d00a831fcd3d2b14354e0629..4dc97b9f65fb0c6ee8137bb90a80efd0bfd0908d 100644 (file)
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -265,6 +265,7 @@ enum tpm2_startup_types {
 enum tpm2_cc_attrs {
        TPM2_CC_ATTR_CHANDLES   = 25,
        TPM2_CC_ATTR_RHANDLE    = 28,
+       TPM2_CC_ATTR_VENDOR     = 29,
 };
 
 #define TPM_VID_INTEL    0x8086