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author | Roberto Sassu <roberto.sassu@huawei.com> | 2019-05-29 15:30:33 +0200 |
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committer | Mimi Zohar <zohar@linux.ibm.com> | 2019-05-30 05:18:25 +0200 |
commit | 221be106d75c1b511973301542f47d6000d0b63e (patch) | |
tree | 18f8246e67943de8fc8f5d9ebe2fcb927b8ed391 /security/integrity/evm | |
parent | ima: fix wrong signed policy requirement when not appraising (diff) | |
download | linux-221be106d75c1b511973301542f47d6000d0b63e.tar.xz linux-221be106d75c1b511973301542f47d6000d0b63e.zip |
evm: check hash algorithm passed to init_desc()
This patch prevents memory access beyond the evm_tfm array by checking the
validity of the index (hash algorithm) passed to init_desc(). The hash
algorithm can be arbitrarily set if the security.ima xattr type is not
EVM_XATTR_HMAC.
Fixes: 5feeb61183dde ("evm: Allow non-SHA1 digital signatures")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Cc: stable@vger.kernel.org
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Diffstat (limited to 'security/integrity/evm')
-rw-r--r-- | security/integrity/evm/evm_crypto.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/security/integrity/evm/evm_crypto.c b/security/integrity/evm/evm_crypto.c index e11564eb645b..82a38e801ee4 100644 --- a/security/integrity/evm/evm_crypto.c +++ b/security/integrity/evm/evm_crypto.c @@ -89,6 +89,9 @@ static struct shash_desc *init_desc(char type, uint8_t hash_algo) tfm = &hmac_tfm; algo = evm_hmac; } else { + if (hash_algo >= HASH_ALGO__LAST) + return ERR_PTR(-EINVAL); + tfm = &evm_tfm[hash_algo]; algo = hash_algo_name[hash_algo]; } |