Re: [syzbot] Re: [syzbot] [net?] WARNING in hsr_fill_frame_info

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Subject: Re: [syzbot] [net?] WARNING in hsr_fill_frame_info
Author: lizhi.xu@xxxxxxxxxxxxx

missing lock before call hsr_forward_skb

#syz test

diff --git a/net/hsr/hsr_slave.c b/net/hsr/hsr_slave.c
index af6cf64a00e0..3971dbc0644a 100644
--- a/net/hsr/hsr_slave.c
+++ b/net/hsr/hsr_slave.c
@@ -67,7 +67,9 @@ static rx_handler_result_t hsr_handle_frame(struct sk_buff **pskb)
 		skb_set_network_header(skb, ETH_HLEN + HSR_HLEN);
 	skb_reset_mac_len(skb);
 
+	spin_lock_bh(&hsr->seqnr_lock);
 	hsr_forward_skb(skb, port);
+	spin_unlock_bh(&hsr->seqnr_lock);
 
 finish_consume:
 	return RX_HANDLER_CONSUMED;