The buffer 'derived_buf' in the function get_derived_key() must be
allocated dynamically in order to make room for an arbitrary length
master key.
Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxx>
---
security/keys/encrypted_defined.c | 15 +++++++++++++--
1 files changed, 13 insertions(+), 2 deletions(-)
diff --git a/security/keys/encrypted_defined.c b/security/keys/encrypted_defined.c
index 5331925..65d9b13 100644
--- a/security/keys/encrypted_defined.c
+++ b/security/keys/encrypted_defined.c
@@ -289,10 +289,20 @@ enum derived_key_type { ENC_KEY, AUTH_KEY };
static int get_derived_key(char *derived_key, enum derived_key_type key_type,
void *master_key, unsigned int master_keylen)
{
- char derived_buf[hash_size + 10];
+ char *derived_buf;
int ret;
+ unsigned int derived_buf_len;
+
+ derived_buf_len = strlen("AUTH_KEY") + 1 + master_keylen;
+ if (derived_buf_len < hash_size)
+ derived_buf_len = hash_size;
+
+ derived_buf = kzalloc(derived_buf_len, GFP_KERNEL);
+ if (!derived_buf) {
+ pr_err("encrypted_key: out of memory\n");
+ return -ENOMEM;
+ }
- memset(derived_buf, 0, sizeof derived_buf);
if (key_type)
strcpy(derived_buf, "AUTH_KEY");
else
@@ -301,6 +311,7 @@ static int get_derived_key(char *derived_key, enum derived_key_type key_type,
memcpy(derived_buf + strlen(derived_buf) + 1, master_key,
master_keylen);
ret = calc_hash(derived_key, derived_buf, sizeof derived_buf);
+ kfree(derived_buf);
return ret;
}
--
1.7.2.3
Attachment:
smime.p7s
Description: S/MIME cryptographic signature
