From f04787555f4c9b1d5913e6c0f1413d6eecc47527 Mon Sep 17 00:00:00 2001 From: Daniele Alessandrelli Date: Wed, 3 Feb 2021 11:28:37 +0000 Subject: [PATCH] crypto: ecdh_helper - Ensure 'len >= secret.len' in decode_key() [ Upstream commit a53ab94eb6850c3657392e2d2ce9b38c387a2633 ] 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. Fixes: 3c4b23901a0c7 ("crypto: ecdh - Add ECDH software support") Signed-off-by: Daniele Alessandrelli Signed-off-by: Herbert Xu Signed-off-by: Sasha Levin --- crypto/ecdh_helper.c | 3 +++ 1 file changed, 3 insertions(+) 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(¶ms->curve_id, ptr, sizeof(params->curve_id)); ptr = ecdh_unpack_data(¶ms->key_size, ptr, sizeof(params->key_size)); if (secret.len != crypto_ecdh_key_len(params))