[PATCH 6.18 047/333] net: spacemit: Fix error handling in emac_alloc_rx_desc_buffers()

Greg Kroah-Hartman
2026-03-17T17:07:28Z

From: Vivian Wang <wangruikang@iscas.ac.cn>

[ Upstream commit 3aa1417803c1833cbd5bacb7e6a6489a196f2519 ]

Even if we get a dma_mapping_error() while mapping an RX buffer, we
should still update rx_ring->head to ensure that the buffers we were
able to allocate and map are used. Fix this by breaking out to the
existing code after the loop, analogous to the existing handling for skb
allocation failure.

Fixes: bfec6d7f2001 ("net: spacemit: Add K1 Ethernet MAC")
Signed-off-by: Vivian Wang <wangruikang@iscas.ac.cn>
Link: https://patch.msgid.link/20260305-k1-ethernet-more-fixes-v2-1-e4e434d65055@iscas.ac.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/spacemit/k1_emac.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/spacemit/k1_emac.c b/drivers/net/ethernet/spacemit/k1_emac.c
index b49c4708bf9eb..5de69a105168a 100644
--- a/drivers/net/ethernet/spacemit/k1_emac.c
+++ b/drivers/net/ethernet/spacemit/k1_emac.c
@@ -582,7 +582,9 @@ static void emac_alloc_rx_desc_buffers(struct emac_priv *priv)
DMA_FROM_DEVICE);
if (dma_mapping_error(&priv->pdev->dev, rx_buf->dma_addr)) {
dev_err_ratelimited(&ndev->dev, "Mapping skb failed\n");
- goto err_free_skb;
+ dev_kfree_skb_any(skb);
+ rx_buf->skb = NULL;
+ break;
}

rx_desc_addr = &((struct emac_desc *)rx_ring->desc_addr)[i];
@@ -607,10 +609,6 @@ static void emac_alloc_rx_desc_buffers(struct emac_priv *priv)

rx_ring->head = i;
return;
-
-err_free_skb:
- dev_kfree_skb_any(skb);
- rx_buf->skb = NULL;
}

/* Returns number of packets received */
--
2.51.0