net: hsr: fix hsr_init_sk() vs network/transport headers.

JIRA: https://issues.redhat.com/browse/RHEL-84580

commit 9cfb5e7
Author: Eric Dumazet <edumazet@google.com>
Date:   Fri Nov 22 17:13:43 2024 +0000

    net: hsr: fix hsr_init_sk() vs network/transport headers.
    
    Following sequence in hsr_init_sk() is invalid :
    
        skb_reset_mac_header(skb);
        skb_reset_mac_len(skb);
        skb_reset_network_header(skb);
        skb_reset_transport_header(skb);
    
    It is invalid because skb_reset_mac_len() needs the correct
    network header, which should be after the mac header.
    
    This patch moves the skb_reset_network_header()
    and skb_reset_transport_header() before
    the call to dev_hard_header().
    
    As a result skb->mac_len is no longer set to a value
    close to 65535.
    
    Fixes: 48b491a ("net: hsr: fix mac_len checks")
    Signed-off-by: Eric Dumazet <edumazet@google.com>
    Cc: George McCollister <george.mccollister@gmail.com>
    Link: https://patch.msgid.link/20241122171343.897551-1-edumazet@google.com
    Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Signed-off-by: Felix Maurer <fmaurer@redhat.com>

Author: fmaurer-rh

net/hsr/hsr_device.c

@@ -260,15 +260,15 @@ static struct sk_buff *hsr_init_skb(struct hsr_port *master)
 	skb->dev = master->dev;
 	skb->priority = TC_PRIO_CONTROL;
 
+	skb_reset_network_header(skb);
+	skb_reset_transport_header(skb);
 	if (dev_hard_header(skb, skb->dev, ETH_P_PRP,
 			    hsr->sup_multicast_addr,
 			    skb->dev->dev_addr, skb->len) <= 0)
 		goto out;
 
 	skb_reset_mac_header(skb);
 	skb_reset_mac_len(skb);
-	skb_reset_network_header(skb);
-	skb_reset_transport_header(skb);
 
 	return skb;
 out: