diff options
| author | Seth Forshee <seth.forshee@canonical.com> | 2016-08-01 08:19:10 -0500 |
|---|---|---|
| committer | Mimi Zohar <zohar@linux.vnet.ibm.com> | 2016-11-13 22:50:11 -0500 |
| commit | b4bfec7f4a86424b114f94f41c4e1841ec102df3 (patch) | |
| tree | 9f4a668c3d28ef3de0743d3dda285829b38a85a3 /security/integrity/ima/ima_appraise.c | |
| parent | 5465d02a4970990d8ec692c7539af5fdde95e613 (diff) | |
security/integrity: Harden against malformed xattrs
In general the handling of IMA/EVM xattrs is good, but I found
a few locations where either the xattr size or the value of the
type field in the xattr are not checked. Add a few simple checks
to these locations to prevent malformed or malicious xattrs from
causing problems.
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Diffstat (limited to 'security/integrity/ima/ima_appraise.c')
| -rw-r--r-- | security/integrity/ima/ima_appraise.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c index a705598ced5f..1fd9539a969d 100644 --- a/security/integrity/ima/ima_appraise.c +++ b/security/integrity/ima/ima_appraise.c @@ -130,6 +130,7 @@ enum hash_algo ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, int xattr_len) { struct signature_v2_hdr *sig; + enum hash_algo ret; if (!xattr_value || xattr_len < 2) /* return default hash algo */ @@ -143,7 +144,9 @@ enum hash_algo ima_get_hash_algo(struct evm_ima_xattr_data *xattr_value, return sig->hash_algo; break; case IMA_XATTR_DIGEST_NG: - return xattr_value->digest[0]; + ret = xattr_value->digest[0]; + if (ret < HASH_ALGO__LAST) + return ret; break; case IMA_XATTR_DIGEST: /* this is for backward compatibility */ |