Re: [PATCH] wan: dscc4: add checks for dma mapping errors
flat view
From: Francois Romieu <romieu@fr.zoreil.com>
Date: 2017-08-07 21:59:58
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lkml
Alexey Khoroshilov [off-list ref] :
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 <redacted>
Please amend your subject line as: Subject: [PATCH net-next v2 1/1] dscc4: add checks for dma mapping errors. Rationale: davem is not supposed to guess the branch the patch should be applied to. [...]
quoted hunk ↗ jump to hunk
diff --git a/drivers/net/wan/dscc4.c b/drivers/net/wan/dscc4.c index 799830ffcae2..1a94f0a95b2c 100644 --- a/drivers/net/wan/dscc4.c +++ b/drivers/net/wan/dscc4.c@@ -522,19 +522,27 @@ static inline int try_get_rx_skb(struct dscc4_dev_priv *dpriv, struct RxFD *rx_fd = dpriv->rx_fd + dirty; const int len = RX_MAX(HDLC_MAX_MRU); struct sk_buff *skb; - int ret = 0; + dma_addr_t addr; skb = dev_alloc_skb(len); dpriv->rx_skbuff[dirty] = skb; - if (skb) { - skb->protocol = hdlc_type_trans(skb, dev); - rx_fd->data = cpu_to_le32(pci_map_single(dpriv->pci_priv->pdev, - skb->data, len, PCI_DMA_FROMDEVICE)); - } else { - rx_fd->data = 0; - ret = -1; - } - return ret; + if (!skb) + goto err_out; + + skb->protocol = hdlc_type_trans(skb, dev); + addr = pci_map_single(dpriv->pci_priv->pdev, + skb->data, len, PCI_DMA_FROMDEVICE); + if (pci_dma_mapping_error(dpriv->pci_priv->pdev, addr)) + goto err_free_skb;
Nit: please use a local 'struct pci_dev *pdev = dpriv->pci_priv->pdev;' [...]
quoted hunk ↗ jump to hunk
@@ -1147,14 +1155,22 @@ static netdev_tx_t dscc4_start_xmit(struct sk_buff *skb, struct dscc4_dev_priv *dpriv = dscc4_priv(dev); struct dscc4_pci_priv *ppriv = dpriv->pci_priv; struct TxFD *tx_fd; + dma_addr_t addr; int next; + addr = pci_map_single(ppriv->pdev, skb->data, skb->len, + PCI_DMA_TODEVICE); + if (pci_dma_mapping_error(ppriv->pdev, addr)) { + dev_kfree_skb_any(skb); + dev->stats.tx_errors++;
It should read 'dev->stats.tx_dropped++'. -- Ueimor