From f3c82ade7c59303167d56b0be3e0707751fc45e2 Mon Sep 17 00:00:00 2001 From: Jarkko Sakkinen Date: Wed, 6 Jan 2016 16:43:30 +0200 Subject: [PATCH] tpm: fix checks for policy digest existence in tpm2_seal_trusted() In my original patch sealing with policy was done with dynamically allocated buffer that I changed later into an array so the checks in tpm2-cmd.c became invalid. This patch fixes the issue. Fixes: 5beb0c435bdd ("keys, trusted: seal with a TPM2 authorization policy") Reported-by: Dan Carpenter Signed-off-by: Jarkko Sakkinen Acked-by: Peter Huewe --- drivers/char/tpm/tpm2-cmd.c | 12 ++++-------- include/keys/trusted-type.h | 2 +- security/keys/trusted.c | 11 +++++------ 3 files changed, 10 insertions(+), 15 deletions(-) diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c index 45a634016f95..66e04b41a73d 100644 --- a/drivers/char/tpm/tpm2-cmd.c +++ b/drivers/char/tpm/tpm2-cmd.c @@ -478,20 +478,16 @@ int tpm2_seal_trusted(struct tpm_chip *chip, tpm_buf_append_u8(&buf, payload->migratable); /* public */ - if (options->policydigest) - tpm_buf_append_u16(&buf, 14 + options->digest_len); - else - tpm_buf_append_u16(&buf, 14); - + tpm_buf_append_u16(&buf, 14 + options->policydigest_len); tpm_buf_append_u16(&buf, TPM2_ALG_KEYEDHASH); tpm_buf_append_u16(&buf, hash); /* policy */ - if (options->policydigest) { + if (options->policydigest_len) { tpm_buf_append_u32(&buf, 0); - tpm_buf_append_u16(&buf, options->digest_len); + tpm_buf_append_u16(&buf, options->policydigest_len); tpm_buf_append(&buf, options->policydigest, - options->digest_len); + options->policydigest_len); } else { tpm_buf_append_u32(&buf, TPM2_ATTR_USER_WITH_AUTH); tpm_buf_append_u16(&buf, 0); diff --git a/include/keys/trusted-type.h b/include/keys/trusted-type.h index 42cf2d991bf4..4ea7e55f20b0 100644 --- a/include/keys/trusted-type.h +++ b/include/keys/trusted-type.h @@ -38,7 +38,7 @@ struct trusted_key_options { unsigned char pcrinfo[MAX_PCRINFO_SIZE]; int pcrlock; uint32_t hash; - uint32_t digest_len; + uint32_t policydigest_len; unsigned char policydigest[MAX_DIGEST_SIZE]; uint32_t policyhandle; }; diff --git a/security/keys/trusted.c b/security/keys/trusted.c index 0dcab20cdacd..90d61751ff12 100644 --- a/security/keys/trusted.c +++ b/security/keys/trusted.c @@ -744,6 +744,7 @@ static int getoptions(char *c, struct trusted_key_payload *pay, unsigned long handle; unsigned long lock; unsigned long token_mask = 0; + unsigned int digest_len; int i; int tpm2; @@ -752,7 +753,6 @@ static int getoptions(char *c, struct trusted_key_payload *pay, return tpm2; opt->hash = tpm2 ? HASH_ALGO_SHA256 : HASH_ALGO_SHA1; - opt->digest_len = hash_digest_size[opt->hash]; while ((p = strsep(&c, " \t"))) { if (*p == '\0' || *p == ' ' || *p == '\t') @@ -812,8 +812,6 @@ static int getoptions(char *c, struct trusted_key_payload *pay, for (i = 0; i < HASH_ALGO__LAST; i++) { if (!strcmp(args[0].from, hash_algo_name[i])) { opt->hash = i; - opt->digest_len = - hash_digest_size[opt->hash]; break; } } @@ -825,13 +823,14 @@ static int getoptions(char *c, struct trusted_key_payload *pay, } break; case Opt_policydigest: - if (!tpm2 || - strlen(args[0].from) != (2 * opt->digest_len)) + digest_len = hash_digest_size[opt->hash]; + if (!tpm2 || strlen(args[0].from) != (2 * digest_len)) return -EINVAL; res = hex2bin(opt->policydigest, args[0].from, - opt->digest_len); + digest_len); if (res < 0) return -EINVAL; + opt->policydigest_len = digest_len; break; case Opt_policyhandle: if (!tpm2)