Allow trusted.ko to initialize w/o a TPM. This commit adds checks to the key type callbacks and exported functions to fail when a TPM is not available. Cc: James Morris <jmorris@xxxxxxxxx> Reported-by: Dan Williams <dan.j.williams@xxxxxxxxx> Tested-by: Dan Williams <dan.j.williams@xxxxxxxxx> Fixes: 240730437deb ("KEYS: trusted: explicitly use tpm_chip structure...") Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@xxxxxxxxxxxxxxx> --- v3: - remove unnecessary check for chip in init_trusted() v2: - Remove checks from the key type callbacks because the key type will not be registered. - Cc to James Morris because hopefully we can land this 5.1.0. security/keys/trusted.c | 28 +++++++++++++++++++++++----- 1 file changed, 23 insertions(+), 5 deletions(-) diff --git a/security/keys/trusted.c b/security/keys/trusted.c index ecec672d3a77..efdbf17f3915 100644 --- a/security/keys/trusted.c +++ b/security/keys/trusted.c @@ -135,6 +135,9 @@ int TSS_authhmac(unsigned char *digest, const unsigned char *key, int ret; va_list argp; + if (!chip) + return -ENODEV; + sdesc = init_sdesc(hashalg); if (IS_ERR(sdesc)) { pr_info("trusted_key: can't alloc %s\n", hash_alg); @@ -196,6 +199,9 @@ int TSS_checkhmac1(unsigned char *buffer, va_list argp; int ret; + if (!chip) + return -ENODEV; + bufsize = LOAD32(buffer, TPM_SIZE_OFFSET); tag = LOAD16(buffer, 0); ordinal = command; @@ -363,6 +369,9 @@ int trusted_tpm_send(unsigned char *cmd, size_t buflen) { int rc; + if (!chip) + return -ENODEV; + dump_tpm_buf(cmd); rc = tpm_send(chip, cmd, buflen); dump_tpm_buf(cmd); @@ -429,6 +438,9 @@ int oiap(struct tpm_buf *tb, uint32_t *handle, unsigned char *nonce) { int ret; + if (!chip) + return -ENODEV; + INIT_BUF(tb); store16(tb, TPM_TAG_RQU_COMMAND); store32(tb, TPM_OIAP_SIZE); @@ -1245,9 +1257,13 @@ static int __init init_trusted(void) { int ret; + /* encrypted_keys.ko depends on successful load of this module even if + * TPM is not used. + */ chip = tpm_default_chip(); if (!chip) - return -ENOENT; + return 0; + ret = init_digests(); if (ret < 0) goto err_put; @@ -1269,10 +1285,12 @@ static int __init init_trusted(void) static void __exit cleanup_trusted(void) { - put_device(&chip->dev); - kfree(digests); - trusted_shash_release(); - unregister_key_type(&key_type_trusted); + if (chip) { + put_device(&chip->dev); + kfree(digests); + trusted_shash_release(); + unregister_key_type(&key_type_trusted); + } } late_initcall(init_trusted); -- 2.19.1