net: ti: icssg-prueth: Fix skb handling for XDP_PASS

emac_rx_packet() is a common function for handling traffic
for both xdp and non-xdp use cases. Use common logic for
handling skb with or without xdp to prevent any incorrect
packet processing. This patch fixes ping working with
XDP_PASS for icssg driver.

Fixes: 62aa324 ("net: ti: icssg-prueth: Add XDP support")
Signed-off-by: Meghana Malladi <[email protected]>
Reviewed-by: Jacob Keller <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Author: MeghanaMalladiTI

drivers/net/ethernet/ti/icssg/icssg_common.c

@@ -706,9 +706,9 @@ static int emac_rx_packet(struct prueth_emac *emac, u32 flow_id, u32 *xdp_state)
 	struct page_pool *pool;
 	struct sk_buff *skb;
 	struct xdp_buff xdp;
+	int headroom, ret;
 	u32 *psdata;
 	void *pa;
-	int ret;
 
 	*xdp_state = 0;
 	pool = rx_chn->pg_pool;
@@ -757,22 +757,23 @@ static int emac_rx_packet(struct prueth_emac *emac, u32 flow_id, u32 *xdp_state)
 		xdp_prepare_buff(&xdp, pa, PRUETH_HEADROOM, pkt_len, false);
 
 		*xdp_state = emac_run_xdp(emac, &xdp, page, &pkt_len);
-		if (*xdp_state == ICSSG_XDP_PASS)
-			skb = xdp_build_skb_from_buff(&xdp);
-		else
+		if (*xdp_state != ICSSG_XDP_PASS)
 			goto requeue;
+		headroom = xdp.data - xdp.data_hard_start;
+		pkt_len = xdp.data_end - xdp.data;
 	} else {
-		/* prepare skb and send to n/w stack */
-		skb = napi_build_skb(pa, PAGE_SIZE);
+		headroom = PRUETH_HEADROOM;
 	}
 
+	/* prepare skb and send to n/w stack */
+	skb = napi_build_skb(pa, PAGE_SIZE);
 	if (!skb) {
 		ndev->stats.rx_dropped++;
 		page_pool_recycle_direct(pool, page);
 		goto requeue;
 	}
 
-	skb_reserve(skb, PRUETH_HEADROOM);
+	skb_reserve(skb, headroom);
 	skb_put(skb, pkt_len);
 	skb->dev = ndev;