[PATCH net v2 1/2] net: airoha: Move ndesc initialization at end of airoha_qdma_init_rx_queue()

Lorenzo Bianconi
2026-04-20T08:08:08Z

If queue entry or DMA descriptor list allocation fails in
airoha_qdma_init_rx_queue routine, airoha_qdma_cleanup() will trigger a
NULL pointer dereference running netif_napi_del() for RX queue NAPIs
since netif_napi_add() has never been executed to this particular RX NAPI.
The issue is due to the early ndesc initialization in
airoha_qdma_init_rx_queue() since airoha_qdma_cleanup() relies on ndesc
value to check if the queue is properly initialized. Fix the issue moving
ndesc initialization at end of airoha_qdma_init_tx routine.
Move page_pool allocation after descriptor list allocation in order to
avoid memory leaks if desc allocation fails.

Fixes: 23020f049327 ("net: airoha: Introduce ethernet support for EN7581 SoC")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
---
drivers/net/ethernet/airoha/airoha_eth.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/airoha/airoha_eth.c b/drivers/net/ethernet/airoha/airoha_eth.c
index e1ab15f1ee7d..fc79c456743c 100644
--- a/drivers/net/ethernet/airoha/airoha_eth.c
+++ b/drivers/net/ethernet/airoha/airoha_eth.c
@@ -745,14 +745,18 @@ static int airoha_qdma_init_rx_queue(struct airoha_queue *q,
dma_addr_t dma_addr;

q->buf_size = PAGE_SIZE / 2;
- q->ndesc = ndesc;
q->qdma = qdma;

- q->entry = devm_kzalloc(eth->dev, q->ndesc * sizeof(*q->entry),
+ q->entry = devm_kzalloc(eth->dev, ndesc * sizeof(*q->entry),
GFP_KERNEL);
if (!q->entry)
return -ENOMEM;

+ q->desc = dmam_alloc_coherent(eth->dev, ndesc * sizeof(*q->desc),
+ &dma_addr, GFP_KERNEL);
+ if (!q->desc)
+ return -ENOMEM;
+
q->page_pool = page_pool_create(&pp_params);
if (IS_ERR(q->page_pool)) {
int err = PTR_ERR(q->page_pool);
@@ -761,11 +765,7 @@ static int airoha_qdma_init_rx_queue(struct airoha_queue *q,
return err;
}

- q->desc = dmam_alloc_coherent(eth->dev, q->ndesc * sizeof(*q->desc),
- &dma_addr, GFP_KERNEL);
- if (!q->desc)
- return -ENOMEM;
-
+ q->ndesc = ndesc;
netif_napi_add(eth->napi_dev, &q->napi, airoha_qdma_rx_napi_poll);

airoha_qdma_wr(qdma, REG_RX_RING_BASE(qid), dma_addr);

--
2.53.0