Forwarded: Test for a81f2759d022496b40ab

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Subject: Test for a81f2759d022496b40ab
Author: syoshida@redhat.com

#syz test

diff --git a/net/hsr/hsr_slave.c b/net/hsr/hsr_slave.c
index b87b6a6fe070..979fe4084f86 100644
--- a/net/hsr/hsr_slave.c
+++ b/net/hsr/hsr_slave.c
@@ -63,8 +63,12 @@ static rx_handler_result_t hsr_handle_frame(struct sk_buff **pskb)
 	skb_push(skb, ETH_HLEN);
 	skb_reset_mac_header(skb);
 	if ((!hsr->prot_version && protocol == htons(ETH_P_PRP)) ||
-	    protocol == htons(ETH_P_HSR))
+	    protocol == htons(ETH_P_HSR)) {
+		if (skb->len < ETH_HLEN + HSR_HLEN)
+			goto finish_pass;
+
 		skb_set_network_header(skb, ETH_HLEN + HSR_HLEN);
+	}
 	skb_reset_mac_len(skb);
 
 	/* Only the frames received over the interlink port will assign a