Forwarded: [PATCH v2 net] net/core : fix KMSAN: uninit value in tipc_rcv

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Subject: [PATCH v2 net] net/core : fix KMSAN: uninit value in tipc_rcv
Author: hariconscious@xxxxxxxxx

From: HariKrishna Sagala <hariconscious@xxxxxxxxx>

---

#syz test

diff --git a/net/tipc/node.c b/net/tipc/node.c
index a07fb073368c..f64f653e775a 100644
--- a/net/tipc/node.c
+++ b/net/tipc/node.c
@@ -2117,6 +2117,8 @@ void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b)
 		goto discard;
 	__skb_queue_head_init(&xmitq);
 	hdr = buf_msg(skb);
+	if(!hdr)
+		return -EINVAL;
 	usr = msg_user(hdr);
 	bc_ack = msg_bcast_ack(hdr);