[PATCH 6.12 0652/1102] net: bcmasp: clear txcb->last before writing each descriptor

6.12-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Justin Chen <justin.chen@broadcom.com>

[ Upstream commit 18e5e0ec0e9282c897e2aa81a3e43ccaee03b003 ]

bcmasp_xmit() only wrote txcb->last = true for the final fragment
of an SKB; non-final fragments left the field untouched.  If a
descriptor slot was reused while it still held a stale true from
a previous SKB (possible when tx_spb_ring_full() underreported
fullness), bcmasp_tx_reclaim() would see last == true mid-SKB and
call dev_consume_skb_any() prematurely, freeing the sk_buff while
its remaining fragments were still in flight.

Unconditionally clear txcb->last before the conditional set so every
descriptor slot starts from a known false state regardless of what a
prior transmission left behind.

Fixes: 490cb412007d ("net: bcmasp: Add support for ASP2.0 Ethernet controller")
Signed-off-by: Justin Chen <justin.chen@broadcom.com>
Signed-off-by: Danesh Petigara <redacted>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://patch.msgid.link/20260831184235.4133351-2-danesh.petigara@broadcom.com (local)
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/net/ethernet/broadcom/asp2/bcmasp_intf.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/ethernet/broadcom/asp2/bcmasp_intf.c b/drivers/net/ethernet/broadcom/asp2/bcmasp_intf.c
index 5ab4be83122d9..6232dc6c6c6ba 100644
--- a/drivers/net/ethernet/broadcom/asp2/bcmasp_intf.c
+++ b/drivers/net/ethernet/broadcom/asp2/bcmasp_intf.c

@@ -333,6 +333,7 @@ static netdev_tx_t bcmasp_xmit(struct sk_buff *skb, struct net_device *dev)
 		txcb->bytes_sent = total_bytes;
 		dma_unmap_addr_set(txcb, dma_addr, mapping);
 		dma_unmap_len_set(txcb, dma_len, size);
+		txcb->last = false;
 		if (!i) {
 			desc->flags |= DESC_SOF;
 			if (csum_hw)

-- 
2.53.0