diff mbox series

crypto: ecdh_helper - Ensure 'len >= secret.len' in decode_key()

Message ID 20210203112837.203732-1-daniele.alessandrelli@linux.intel.com
State New
Headers show
Series crypto: ecdh_helper - Ensure 'len >= secret.len' in decode_key() | expand

Commit Message

Daniele Alessandrelli Feb. 3, 2021, 11:28 a.m. UTC
From: Daniele Alessandrelli <daniele.alessandrelli@intel.com>

The length ('len' parameter) passed to crypto_ecdh_decode_key() is never
checked against the length encoded in the passed buffer ('buf'
parameter). This could lead to an out-of-bounds access when the passed
length is less than the encoded length.

Add a check to prevent that.

Signed-off-by: Daniele Alessandrelli <daniele.alessandrelli@intel.com>
---
 crypto/ecdh_helper.c | 3 +++
 1 file changed, 3 insertions(+)

Comments

Herbert Xu Feb. 10, 2021, 7:22 a.m. UTC | #1
On Wed, Feb 03, 2021 at 11:28:37AM +0000, Daniele Alessandrelli wrote:
> From: Daniele Alessandrelli <daniele.alessandrelli@intel.com>

> 

> The length ('len' parameter) passed to crypto_ecdh_decode_key() is never

> checked against the length encoded in the passed buffer ('buf'

> parameter). This could lead to an out-of-bounds access when the passed

> length is less than the encoded length.

> 

> Add a check to prevent that.

> 

> Signed-off-by: Daniele Alessandrelli <daniele.alessandrelli@intel.com>

> ---

>  crypto/ecdh_helper.c | 3 +++

>  1 file changed, 3 insertions(+)


Patch applied.  Thanks.
-- 
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
diff mbox series

Patch

diff --git a/crypto/ecdh_helper.c b/crypto/ecdh_helper.c
index 66fcb2ea8154..fca63b559f65 100644
--- a/crypto/ecdh_helper.c
+++ b/crypto/ecdh_helper.c
@@ -67,6 +67,9 @@  int crypto_ecdh_decode_key(const char *buf, unsigned int len,
 	if (secret.type != CRYPTO_KPP_SECRET_TYPE_ECDH)
 		return -EINVAL;
 
+	if (unlikely(len < secret.len))
+		return -EINVAL;
+
 	ptr = ecdh_unpack_data(&params->curve_id, ptr, sizeof(params->curve_id));
 	ptr = ecdh_unpack_data(&params->key_size, ptr, sizeof(params->key_size));
 	if (secret.len != crypto_ecdh_key_len(params))