From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Date: Thu, 28 Jul 2022 16:50:48 -0700
Subject: Bluetooth: ISO: Fix info leak in iso_sock_getsockopt()
Patch-mainline: v6.0-rc1
Git-commit: 0eee4995f40573f65ed67cea4d20fcf389d353de
References: jsc#PED-1407

The C standard rules for when struct holes are zeroed out are slightly
weird.  The existing assignments might initialize everything, but GCC
is allowed to (and does sometimes) leave the struct holes uninitialized,
so instead of using yet another variable and copy the QoS settings just
use a pointer to the stored QoS settings.

Fixes: ccf74f2390d60 ("Bluetooth: Add BTPROTO_ISO socket type")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Acked-by: Lee, Chun-Yi <jlee@suse.com>
---
 net/bluetooth/iso.c |   10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

--- a/net/bluetooth/iso.c
+++ b/net/bluetooth/iso.c
@@ -1235,7 +1235,7 @@ static int iso_sock_getsockopt(struct so
 {
 	struct sock *sk = sock->sk;
 	int len, err = 0;
-	struct bt_iso_qos qos;
+	struct bt_iso_qos *qos;
 	u8 base_len;
 	u8 *base;
 
@@ -1261,12 +1261,12 @@ static int iso_sock_getsockopt(struct so
 
 	case BT_ISO_QOS:
 		if (sk->sk_state == BT_CONNECTED || sk->sk_state == BT_CONNECT2)
-			qos = iso_pi(sk)->conn->hcon->iso_qos;
+			qos = &iso_pi(sk)->conn->hcon->iso_qos;
 		else
-			qos = iso_pi(sk)->qos;
+			qos = &iso_pi(sk)->qos;
 
-		len = min_t(unsigned int, len, sizeof(qos));
-		if (copy_to_user(optval, (char *)&qos, len))
+		len = min_t(unsigned int, len, sizeof(*qos));
+		if (copy_to_user(optval, qos, len))
 			err = -EFAULT;
 
 		break;