From: Jonas Jensen Date: Mon, 25 Aug 2014 14:22:22 +0000 (+0200) Subject: net: moxa: replace build_skb() with netdev_alloc_skb_ip_align() / memcpy() X-Git-Tag: v3.17-rc5~41^2~47 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=9fe1b3bc8d9182e950a744e4a47187420efa67f3;p=linux.git net: moxa: replace build_skb() with netdev_alloc_skb_ip_align() / memcpy() build_skb() is used to make skbs out of existing RX ring memory which is bad because the RX ring is allocated only once, on probe. Memory corruption occur because said memory is reclaimed, i.e. __kfree_skb() (and eventually put_page()). Replace build_skb() with netdev_alloc_skb_ip_align() and use memcpy(). Remove SKB_DATA_ALIGN() from RX buffer size while we're at it. Addresses https://bugzilla.kernel.org/show_bug.cgi?id=69041 Signed-off-by: Jonas Jensen Signed-off-by: David S. Miller --- diff --git a/drivers/net/ethernet/moxa/moxart_ether.c b/drivers/net/ethernet/moxa/moxart_ether.c index eed70d9f0d9d..d66058d5c429 100644 --- a/drivers/net/ethernet/moxa/moxart_ether.c +++ b/drivers/net/ethernet/moxa/moxart_ether.c @@ -226,13 +226,15 @@ static int moxart_rx_poll(struct napi_struct *napi, int budget) if (len > RX_BUF_SIZE) len = RX_BUF_SIZE; - skb = build_skb(priv->rx_buf[rx_head], priv->rx_buf_size); + skb = netdev_alloc_skb_ip_align(ndev, len); + if (unlikely(!skb)) { - net_dbg_ratelimited("build_skb failed\n"); + net_dbg_ratelimited("netdev_alloc_skb_ip_align failed\n"); priv->stats.rx_dropped++; priv->stats.rx_errors++; } + memcpy(skb->data, priv->rx_buf[rx_head], len); skb_put(skb, len); skb->protocol = eth_type_trans(skb, ndev); napi_gro_receive(&priv->napi, skb); @@ -464,8 +466,7 @@ static int moxart_mac_probe(struct platform_device *pdev) spin_lock_init(&priv->txlock); priv->tx_buf_size = TX_BUF_SIZE; - priv->rx_buf_size = RX_BUF_SIZE + - SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); + priv->rx_buf_size = RX_BUF_SIZE; priv->tx_desc_base = dma_alloc_coherent(NULL, TX_REG_DESC_SIZE * TX_DESC_NUM, &priv->tx_base,