mt76: fix handling full tx queues in mt76_dma_tx_queue_skb_raw

Fixes a theoretical issue where it could potentially overwrite an existing
descriptor entry (and leaking its skb)

Signed-off-by: Felix Fietkau <nbd@nbd.name>
This commit is contained in:
Felix Fietkau
2020-01-20 12:08:30 +01:00
parent 5ffc6b5a98
commit 93eaec7625

View File

@@ -271,10 +271,13 @@ mt76_dma_tx_queue_skb_raw(struct mt76_dev *dev, enum mt76_txq_id qid,
struct mt76_queue_buf buf;
dma_addr_t addr;
if (q->queued + 1 >= q->ndesc - 1)
goto error;
addr = dma_map_single(dev->dev, skb->data, skb->len,
DMA_TO_DEVICE);
if (unlikely(dma_mapping_error(dev->dev, addr)))
return -ENOMEM;
goto error;
buf.addr = addr;
buf.len = skb->len;
@@ -285,6 +288,10 @@ mt76_dma_tx_queue_skb_raw(struct mt76_dev *dev, enum mt76_txq_id qid,
spin_unlock_bh(&q->lock);
return 0;
error:
dev_kfree_skb(skb);
return -ENOMEM;
}
static int