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: Dan Williams dan.j.williams@intel.com Cc: stable@vger.kernel.org Fixes: 240730437deb ("KEYS: trusted: explicitly use tpm_chip structure...") Signed-off-by: Jarkko Sakkinen jarkko.sakkinen@linux.intel.com --- security/keys/trusted.c | 46 +++++++++++++++++++++++++++++++++++------ 1 file changed, 40 insertions(+), 6 deletions(-)

diff --git a/security/keys/trusted.c b/security/keys/trusted.c index ecec672d3a77..13fb1068e371 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); @@ -967,6 +979,9 @@ static int trusted_instantiate(struct key *key, size_t key_len; int tpm2;

+ if (!chip) + return -ENODEV; + tpm2 = tpm_is_tpm2(chip); if (tpm2 < 0) return tpm2; @@ -1050,6 +1065,9 @@ static void trusted_rcu_free(struct rcu_head *rcu) { struct trusted_key_payload *p;

+ if (!chip) + return; + p = container_of(rcu, struct trusted_key_payload, rcu); kzfree(p); } @@ -1066,6 +1084,9 @@ static int trusted_update(struct key *key, struct key_preparsed_payload *prep) char *datablob; int ret = 0;

+ if (!chip) + return -ENODEV; + if (key_is_negative(key)) return -ENOKEY; p = key->payload.data[0]; @@ -1144,6 +1165,9 @@ static long trusted_read(const struct key *key, char __user *buffer, char *bufp; int i;

+ if (!chip) + return -ENODEV; + p = dereference_key_locked(key); if (!p) return -EINVAL; @@ -1170,6 +1194,9 @@ static long trusted_read(const struct key *key, char __user *buffer, */ static void trusted_destroy(struct key *key) { + if (!chip) + return; + kzfree(key->payload.data[0]); }

@@ -1245,9 +1272,13 @@ 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; @@ -1263,16 +1294,19 @@ static int __init init_trusted(void) err_free: kfree(digests); err_put: - put_device(&chip->dev); + if (chip) + put_device(&chip->dev); return ret; }

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);