Commit ec1da08d authored Feb 22, 2014 by andrea merello Committed by John W. Linville Feb 28, 2014

rtl818x: check for pci_map_single() success when initializing RX ring



During initialization a number of RX skbs are allocated and mapped
for DMA.
Currently if pci_map_single() fails, it will result in passing to the
HW a wrong DMA address (to write to!).

This patch adds check for this condition and eventually causes the
driver not to initialize, avoiding at least dangerous DMAs.

Signed-off-by: Andrea Merello <andrea.merello@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

parent 0269da28

drivers/net/wireless/rtl818x/rtl8180/dev.c

+7 −0

Original line number	Diff line number	Diff line
		@@ -483,6 +483,13 @@ static int rtl8180_init_rx_ring(struct ieee80211_hw *dev)
		mapping = (dma_addr_t *)skb->cb;
		*mapping = pci_map_single(priv->pdev, skb_tail_pointer(skb),
		MAX_RX_SIZE, PCI_DMA_FROMDEVICE);

		if (pci_dma_mapping_error(priv->pdev, *mapping)) {
		kfree_skb(skb);
		wiphy_err(dev->wiphy, "Cannot map DMA for RX skb\n");
		return -ENOMEM;
		}

		entry->rx_buf = cpu_to_le32(*mapping);
		entry->flags = cpu_to_le32(RTL818X_RX_DESC_FLAG_OWN \|
		MAX_RX_SIZE);