fix possible stack overflow

sudden6 · sudden6 · commit 1b02bad36864 · 2021-12-05T14:20:00.000+01:00
CRYPTO_SIZE is used in a subtraction as second argument and instead of
subtracting then intended value only '1' is subtracted due to operator
precedence rules and missing braces.
diff --git a/toxcore/DHT.c b/toxcore/DHT.c
@@ -295,7 +295,7 @@ void dht_get_shared_key_sent(DHT *dht, uint8_t *shared_key, const uint8_t *publi
     get_shared_key(dht->mono_time, &dht->shared_keys_sent, shared_key, dht->self_secret_key, public_key);
 }
 
-#define CRYPTO_SIZE 1 + CRYPTO_PUBLIC_KEY_SIZE * 2 + CRYPTO_NONCE_SIZE
+#define CRYPTO_SIZE (1 + CRYPTO_PUBLIC_KEY_SIZE * 2 + CRYPTO_NONCE_SIZE)
 
 /* Create a request to peer.
  * send_public_key and send_secret_key are the pub/secret keys of the sender.

Original file line number	Diff line number	Diff line change
`@@ -295,7 +295,7 @@ void dht_get_shared_key_sent(DHT dht, uint8_t shared_key, const uint8_t *publi`
`295`	`295`	`get_shared_key(dht->mono_time, &dht->shared_keys_sent, shared_key, dht->self_secret_key, public_key);`
`296`	`296`	`}`
`297`	`297`
`298`		`-#define CRYPTO_SIZE 1 + CRYPTO_PUBLIC_KEY_SIZE * 2 + CRYPTO_NONCE_SIZE`
	`298`	`+#define CRYPTO_SIZE (1 + CRYPTO_PUBLIC_KEY_SIZE * 2 + CRYPTO_NONCE_SIZE)`
`299`	`299`
`300`	`300`	`/* Create a request to peer.`
`301`	`301`	`* send_public_key and send_secret_key are the pub/secret keys of the sender.`