[PATCH net v3] net: ethernet: ti: am65-cpsw-nuss: Fix skb size by accounting for skb_shared_info

[Chintan Vankar <c-vankar@ti.com>]

While transitioning from netdev_alloc_ip_align() to build_skb(), memory
for the "skb_shared_info" member of an "skb" was not allocated. Fix this
by allocating "PAGE_SIZE" as the skb length, accounting for the packet
length, headroom and tailroom, thereby including the required memory space
for skb_shared_info.

Fixes: 8acacc40f733 ("net: ethernet: ti: am65-cpsw: Add minimal XDP support")
Reviewed-by: Siddharth Vadapalli <s-vadapalli@ti.com>
Signed-off-by: Chintan Vankar <c-vankar@ti.com>
---

This patch is based on the commit 'af80679632063' of origin/main branch of
Linux-net repository.

Link to v2: 
https://lore.kernel.org/r/20250626051226.2418638-1-c-vankar@ti.com/

Changes from v2 to v3: 
- Updated skb length with the PAGE_SIZE as suggested by Jakub Kicinski.

 drivers/net/ethernet/ti/am65-cpsw-nuss.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.c b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
index f20d1ff192ef..231ca141331f 100644
--- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c
+++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
@@ -856,8 +856,6 @@ static struct sk_buff *am65_cpsw_build_skb(void *page_addr,
 {
 	struct sk_buff *skb;
 
-	len += AM65_CPSW_HEADROOM;
-
 	skb = build_skb(page_addr, len);
 	if (unlikely(!skb))
 		return NULL;
@@ -1344,7 +1342,7 @@ static int am65_cpsw_nuss_rx_packets(struct am65_cpsw_rx_flow *flow,
 	}
 
 	skb = am65_cpsw_build_skb(page_addr, ndev,
-				  AM65_CPSW_MAX_PACKET_SIZE, headroom);
+				  PAGE_SIZE, headroom);
 	if (unlikely(!skb)) {
 		new_page = page;
 		goto requeue;
-- 
2.34.1