crypto: dh - Don't permit 'key' or 'g' size longer than 'p'

[thirdparty/kernel/stable.git] / crypto / dh_helper.c

diff --git a/crypto/dh_helper.c b/crypto/dh_helper.c
index 788a9e5729187434420db3ae41bdcd1de407a17a..24fdb2ecaa85dd9ad20d223898e94503f4307c3c 100644 (file)
--- a/crypto/dh_helper.c
+++ b/crypto/dh_helper.c
@@ -83,6 +83,14 @@ int crypto_dh_decode_key(const char *buf, unsigned int len, struct dh *params)
        if (secret.len != crypto_dh_key_len(params))
                return -EINVAL;
 
+       /*
+        * Don't permit the buffer for 'key' or 'g' to be larger than 'p', since
+        * some drivers assume otherwise.
+        */
+       if (params->key_size > params->p_size ||
+           params->g_size > params->p_size)
+               return -EINVAL;
+
        /* Don't allocate memory. Set pointers to data within
         * the given buffer
         */