[PATCH net-next v10 6/8] hsr: Assign a socket for cloned skbs

The cloned skb does not have the socket recorded of the original skb
because skb_clone() clears sk_buff::sk. The original skb is never
submitted but freed in hsr_forward_skb(). skb_tstamp_tx() will only
submit timestamp information to the sender if the socket is recorded and
the TS flags are available.

As of the recent changes everything is available except the socket and
the requested timestamp gets lost.

This does not consider PRP part of the stack. The specification says
that PTP-PRP packets do not have the RCT therefore these packets can be
sent directly from userland skipping the stack.

Assign the socket of the original skb to the clone so the timestamp is
forwarded to the user.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
 net/hsr/hsr_forward.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/net/hsr/hsr_forward.c b/net/hsr/hsr_forward.c
index d2a11d4560309..85c8dd61ee6f8 100644
--- a/net/hsr/hsr_forward.c
+++ b/net/hsr/hsr_forward.c

@@ -12,6 +12,7 @@
 #include <linux/skbuff.h>
 #include <linux/etherdevice.h>
 #include <linux/if_vlan.h>
+#include <net/sock.h>
 #include "hsr_main.h"
 #include "hsr_framereg.h"
 

@@ -347,6 +348,9 @@ struct sk_buff *hsr_create_tagged_frame(struct hsr_frame_info *frame,
 	if (!skb)
 		return NULL;
 
+	if (frame->req_tx_port != HSR_PT_NONE && frame->skb_std->sk)
+		skb_set_owner_w(skb, frame->skb_std->sk);
+
 	if (port->dev->features & NETIF_F_HW_HSR_TAG_INS)
 		return skb;
 

@@ -581,6 +585,8 @@ static void hsr_forward_do(struct hsr_frame_info *frame)
 		 */
 		if (frame->has_hsr_header && frame->skb_std) {
 			skb = skb_clone(frame->skb_std, GFP_ATOMIC);
+			if (skb && frame->skb_std->sk)
+				skb_set_owner_w(skb, frame->skb_std->sk);
 			goto inject_into_stack;
 		}
 

-- 
2.55.0