[PATCH 3.16 140/294] net: systemport: Free DMA coherent descriptors on errors

[Ben Hutchings]

3.16.50-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Florian Fainelli <f.fainelli@xxxxxxxxx>

commit c2062ee3d9615828109ffe8089fbf69bed394d05 upstream.

In case bcm_sysport_init_tx_ring() is not able to allocate ring->cbs, we
would return with an error, and call bcm_sysport_fini_tx_ring() and it
would see that ring->cbs is NULL and do nothing. This would leak the
coherent DMA descriptor area, so we need to free it on error before
returning.

Reported-by: Eric Dumazet <edumazet@xxxxxxxxx>
Fixes: 80105befdb4b ("net: systemport: add Broadcom SYSTEMPORT Ethernet MAC driver")
Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/net/ethernet/broadcom/bcmsysport.c | 2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/net/ethernet/broadcom/bcmsysport.c
+++ b/drivers/net/ethernet/broadcom/bcmsysport.c
@@ -1024,6 +1024,8 @@ static int bcm_sysport_init_tx_ring(stru
 
 	ring->cbs = kzalloc(sizeof(struct bcm_sysport_cb) * size, GFP_KERNEL);
 	if (!ring->cbs) {
+		dma_free_coherent(kdev, sizeof(struct dma_desc),
+				  ring->desc_cpu, ring->desc_dma);
 		netif_err(priv, hw, priv->netdev, "CB allocation failed\n");
 		return -ENOMEM;
 	}