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 <[email protected]> Tested-by: Jarkko Sakkinen <[email protected]> Reviewed-by: Jarkko Sakkinen <[email protected]> Signed-off-by: Jarkko Sakkinen <[email protected]>
kawasaki · Feb 13, 2023 · 85b93bb · 85b93bb
1 parent 1e2714b
commit 85b93bb
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diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
@@ -777,10 +777,12 @@ int tpm2_auto_startup(struct tpm_chip *chip)
 
 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
@@ -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