[PATCH v2] can: isotp: fix isotp_getname() leak

Initialize the sockaddr_can structure to prevent a data leak to user space.

Suggested-by: Cong Wang <redacted>
Reported-by: syzbot+057884e2f453e8afebc8@syzkaller.appspotmail.com
Fixes: e057dd3fc20f ("can: add ISO 15765-2:2016 transport protocol")
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
---
 net/can/isotp.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/can/isotp.c b/net/can/isotp.c
index 7839c3b9e5be..3ef7f78e553b 100644
--- a/net/can/isotp.c
+++ b/net/can/isotp.c

@@ -1153,10 +1153,11 @@ static int isotp_getname(struct socket *sock, struct sockaddr *uaddr, int peer)
 	struct isotp_sock *so = isotp_sk(sk);
 
 	if (peer)
 		return -EOPNOTSUPP;
 
+	memset(addr, 0, sizeof(*addr));
 	addr->can_family = AF_CAN;
 	addr->can_ifindex = so->ifindex;
 	addr->can_addr.tp.rx_id = so->rxid;
 	addr->can_addr.tp.tx_id = so->txid;
 

-- 
2.29.2

On 1/12/21 10:16 AM, Oliver Hartkopp wrote:

Initialize the sockaddr_can structure to prevent a data leak to user space.

Suggested-by: Cong Wang <redacted>
Reported-by: syzbot+057884e2f453e8afebc8@syzkaller.appspotmail.com
Fixes: e057dd3fc20f ("can: add ISO 15765-2:2016 transport protocol")
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>

Applied to linux-can/testing

Tnx,
Marc

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