Re: [PATCH] wan: dscc4: add checks for dma mapping errors
flat view
From: David Miller <davem@davemloft.net>
Date: 2017-08-07 21:06:43
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From: Alexey Khoroshilov <redacted> Date: Fri, 4 Aug 2017 23:23:24 +0300
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>
This is a great example of why it can be irritating to see these mechanical "bug fixes" for drivers very few people use and actually test, which introduces new bugs.
quoted hunk ↗ jump to hunk
@@ -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;
skb recorded here.
+err_free_skb: + dev_kfree_skb_any(skb);
Yet freed here in the error path. dpriv->rx_skbuff[dirty] should not be set to 'skb' until all possibile failure tests have passed.