[PATCH net v3] net: pch_gbe: handle TX skb allocation failure
From: Ruoyu Wang <hidden>
Date: 2026-06-15 12:50:52
Also in:
lkml
Subsystem:
networking drivers, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
pch_gbe_alloc_tx_buffers() allocates an skb for each TX descriptor and
then passes the returned pointer to skb_reserve(). If netdev_alloc_skb()
fails, skb_reserve() dereferences NULL.
Make pch_gbe_alloc_tx_buffers() return an error when an skb allocation
fails. On failure, let pch_gbe_alloc_tx_buffers() clean the partially
allocated TX ring before returning the error. While bringing the device
up, release the RX buffer pool through a shared cleanup helper before
unwinding the IRQ setup.
Fixes: 77555ee72282 ("net: Add Gigabit Ethernet driver of Topcliff PCH")
Signed-off-by: Ruoyu Wang <redacted>
---
Changes in v3:
- Move the partial TX ring cleanup into pch_gbe_alloc_tx_buffers(), as
suggested by Simon Horman.
Changes in v2:
- Add the kernel-doc return value description for
pch_gbe_alloc_tx_buffers().
.../ethernet/oki-semi/pch_gbe/pch_gbe_main.c | 38 ++++++++++++++-----
1 file changed, 29 insertions(+), 9 deletions(-)
diff --git a/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c b/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c
index e5a6f59..98091fb 100644
--- a/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c
+++ b/drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c@@ -1411,13 +1411,25 @@ pch_gbe_alloc_rx_buffers_pool(struct pch_gbe_adapter *adapter, return 0; } +static void pch_gbe_free_rx_buffers_pool(struct pch_gbe_adapter *adapter, + struct pch_gbe_rx_ring *rx_ring) +{ + dma_free_coherent(&adapter->pdev->dev, rx_ring->rx_buff_pool_size, + rx_ring->rx_buff_pool, rx_ring->rx_buff_pool_logic); + rx_ring->rx_buff_pool_logic = 0; + rx_ring->rx_buff_pool_size = 0; + rx_ring->rx_buff_pool = NULL; +} + /** * pch_gbe_alloc_tx_buffers - Allocate transmit buffers * @adapter: Board private structure * @tx_ring: Tx descriptor ring + * + * Return: 0 on success, -ENOMEM if a TX skb allocation fails. */ -static void pch_gbe_alloc_tx_buffers(struct pch_gbe_adapter *adapter, - struct pch_gbe_tx_ring *tx_ring) +static int pch_gbe_alloc_tx_buffers(struct pch_gbe_adapter *adapter, + struct pch_gbe_tx_ring *tx_ring) { struct pch_gbe_buffer *buffer_info; struct sk_buff *skb;
@@ -1431,12 +1443,17 @@ static void pch_gbe_alloc_tx_buffers(struct pch_gbe_adapter *adapter, for (i = 0; i < tx_ring->count; i++) { buffer_info = &tx_ring->buffer_info[i]; skb = netdev_alloc_skb(adapter->netdev, bufsz); + if (!skb) { + pch_gbe_clean_tx_ring(adapter, tx_ring); + return -ENOMEM; + } skb_reserve(skb, PCH_GBE_DMA_ALIGN); buffer_info->skb = skb; tx_desc = PCH_GBE_TX_DESC(*tx_ring, i); tx_desc->gbec_status = (DSC_INIT16); } - return; + + return 0; } /**
@@ -1878,7 +1895,12 @@ int pch_gbe_up(struct pch_gbe_adapter *adapter) "Error: can't bring device up - alloc rx buffers pool failed\n"); goto freeirq; } - pch_gbe_alloc_tx_buffers(adapter, tx_ring); + err = pch_gbe_alloc_tx_buffers(adapter, tx_ring); + if (err) { + netdev_err(netdev, + "Error: can't bring device up - alloc tx buffers failed\n"); + goto freebuf; + } pch_gbe_alloc_rx_buffers(adapter, rx_ring, rx_ring->count); adapter->tx_queue_len = netdev->tx_queue_len; pch_gbe_enable_dma_rx(&adapter->hw);
@@ -1892,6 +1914,8 @@ int pch_gbe_up(struct pch_gbe_adapter *adapter) return 0; +freebuf: + pch_gbe_free_rx_buffers_pool(adapter, rx_ring); freeirq: pch_gbe_free_irq(adapter); out:
@@ -1927,11 +1951,7 @@ void pch_gbe_down(struct pch_gbe_adapter *adapter) pch_gbe_clean_tx_ring(adapter, adapter->tx_ring); pch_gbe_clean_rx_ring(adapter, adapter->rx_ring); - dma_free_coherent(&adapter->pdev->dev, rx_ring->rx_buff_pool_size, - rx_ring->rx_buff_pool, rx_ring->rx_buff_pool_logic); - rx_ring->rx_buff_pool_logic = 0; - rx_ring->rx_buff_pool_size = 0; - rx_ring->rx_buff_pool = NULL; + pch_gbe_free_rx_buffers_pool(adapter, rx_ring); } /**
--
2.51.0