tpm: Return tpm2_sessions_init() when null key creation fails

Do not continue tpm2_sessions_init() further if the null key pair creation
fails.

Cc: stable@vger.kernel.org # v6.10+
Fixes: d2add27 ("tpm: Add NULL primary creation")
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>

Author: jarkkojs

drivers/char/tpm/tpm2-sessions.c

@@ -1347,14 +1347,21 @@ static int tpm2_create_null_primary(struct tpm_chip *chip)
  *
  * Derive and context save the null primary and allocate memory in the
  * struct tpm_chip for the authorizations.
+ *
+ * Return:
+ * * 0		- OK
+ * * -errno	- A system error
+ * * TPM_RC	- A TPM error
  */
 int tpm2_sessions_init(struct tpm_chip *chip)
 {
 	int rc;
 
 	rc = tpm2_create_null_primary(chip);
-	if (rc)
-		dev_err(&chip->dev, "TPM: security failed (NULL seed derivation): %d\n", rc);
+	if (rc) {
+		dev_err(&chip->dev, "null key creation failed with %d\n", rc);
+		return rc;
+	}
 
 	chip->auth = kmalloc(sizeof(*chip->auth), GFP_KERNEL);
 	if (!chip->auth)