diff options
| author | Mimi Zohar <zohar@linux.vnet.ibm.com> | 2014-07-28 07:59:49 -0400 |
|---|---|---|
| committer | Mimi Zohar <zohar@linux.vnet.ibm.com> | 2014-09-02 17:03:35 -0400 |
| commit | 9a8d289fbcb7dfd1fc74959e9930b406e76b2002 (patch) | |
| tree | d06d101fc0a24619b7b7d8fff2951ac446e7300d /security | |
| parent | fbff66108352d19b5cffa7dce26d7638c9dd4d70 (diff) | |
ima: fix ima_alloc_atfm()
The patch 3bcced39ea7d: "ima: use ahash API for file hash
calculation" from Feb 26, 2014, leads to the following static checker
warning:
security/integrity/ima/ima_crypto.c:204 ima_alloc_atfm()
error: buffer overflow 'hash_algo_name' 17 <= 17
Unlike shash tfm memory, which is allocated on initialization, the
ahash tfm memory allocation is deferred until needed.
This patch fixes the case where ima_ahash_tfm has not yet been
allocated and the file's signature/hash xattr contains an invalid hash
algorithm. Although we can not verify the xattr, we still need to
measure the file. Use the default IMA hash algorithm.
Changelog:
- set valid algo before testing tfm - based on Dmitry's comment
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Diffstat (limited to 'security')
| -rw-r--r-- | security/integrity/ima/ima_crypto.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c index 0bd732843fe7..2d103dc13d90 100644 --- a/security/integrity/ima/ima_crypto.c +++ b/security/integrity/ima/ima_crypto.c @@ -200,7 +200,10 @@ static struct crypto_ahash *ima_alloc_atfm(enum hash_algo algo) struct crypto_ahash *tfm = ima_ahash_tfm; int rc; - if ((algo != ima_hash_algo && algo < HASH_ALGO__LAST) || !tfm) { + if (algo < 0 || algo >= HASH_ALGO__LAST) + algo = ima_hash_algo; + + if (algo != ima_hash_algo || !tfm) { tfm = crypto_alloc_ahash(hash_algo_name[algo], 0, 0); if (!IS_ERR(tfm)) { if (algo == ima_hash_algo) |