[PATCH] adm80211: add checks for dma mapping errors

From: Alexey Khoroshilov
Date: Fri Dec 02 2016 - 16:53:11 EST


The driver does not check if mapping dma memory succeed.
The patch adds the checks and failure handling.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@xxxxxxxxx>
---
drivers/net/wireless/admtek/adm8211.c | 24 ++++++++++++++++++++++--
1 file changed, 22 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/admtek/adm8211.c b/drivers/net/wireless/admtek/adm8211.c
index 70ecd82d674d..2b4a3eb38dfa 100644
--- a/drivers/net/wireless/admtek/adm8211.c
+++ b/drivers/net/wireless/admtek/adm8211.c
@@ -413,6 +413,13 @@ static void adm8211_interrupt_rci(struct ieee80211_hw *dev)
skb_tail_pointer(newskb),
RX_PKT_SIZE,
PCI_DMA_FROMDEVICE);
+ if (pci_dma_mapping_error(priv->pdev,
+ priv->rx_buffers[entry].mapping)) {
+ priv->rx_buffers[entry].skb = NULL;
+ dev_kfree_skb(newskb);
+ skb = NULL;
+ /* TODO: update rx dropped stats */
+ }
} else {
skb = NULL;
/* TODO: update rx dropped stats */
@@ -1450,6 +1457,12 @@ static int adm8211_init_rings(struct ieee80211_hw *dev)
skb_tail_pointer(rx_info->skb),
RX_PKT_SIZE,
PCI_DMA_FROMDEVICE);
+ if (pci_dma_mapping_error(priv->pdev, rx_info->mapping)) {
+ dev_kfree_skb(rx_info->skb);
+ rx_info->skb = NULL;
+ break;
+ }
+
desc->buffer1 = cpu_to_le32(rx_info->mapping);
desc->status = cpu_to_le32(RDES0_STATUS_OWN | RDES0_STATUS_SQL);
}
@@ -1613,7 +1626,7 @@ static void adm8211_calc_durations(int *dur, int *plcp, size_t payload_len, int
}

/* Transmit skb w/adm8211_tx_hdr (802.11 header created by hardware) */
-static void adm8211_tx_raw(struct ieee80211_hw *dev, struct sk_buff *skb,
+static int adm8211_tx_raw(struct ieee80211_hw *dev, struct sk_buff *skb,
u16 plcp_signal,
size_t hdrlen)
{
@@ -1625,6 +1638,8 @@ static void adm8211_tx_raw(struct ieee80211_hw *dev, struct sk_buff *skb,

mapping = pci_map_single(priv->pdev, skb->data, skb->len,
PCI_DMA_TODEVICE);
+ if (pci_dma_mapping_error(priv->pdev, mapping))
+ return -ENOMEM;

spin_lock_irqsave(&priv->lock, flags);

@@ -1657,6 +1672,8 @@ static void adm8211_tx_raw(struct ieee80211_hw *dev, struct sk_buff *skb,

/* Trigger transmit poll */
ADM8211_CSR_WRITE(TDR, 0);
+
+ return 0;
}

/* Put adm8211_tx_hdr on skb and transmit */
@@ -1710,7 +1727,10 @@ static void adm8211_tx(struct ieee80211_hw *dev,

txhdr->retry_limit = info->control.rates[0].count;

- adm8211_tx_raw(dev, skb, plcp_signal, hdrlen);
+ if (adm8211_tx_raw(dev, skb, plcp_signal, hdrlen)) {
+ /* Drop packet */
+ ieee80211_free_txskb(dev, skb);
+ }
}

static int adm8211_alloc_rings(struct ieee80211_hw *dev)
--
2.7.4