[PATCH net] net: systemport: Free DMA coherent descriptors on errors

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 <redacted>
Fixes: 80105befdb4b ("net: systemport: add Broadcom SYSTEMPORT Ethernet MAC driver")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
 drivers/net/ethernet/broadcom/bcmsysport.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/ethernet/broadcom/bcmsysport.c b/drivers/net/ethernet/broadcom/bcmsysport.c
index e6add99cc31c..c28fa5a8734c 100644
--- a/drivers/net/ethernet/broadcom/bcmsysport.c
+++ b/drivers/net/ethernet/broadcom/bcmsysport.c

@@ -1346,6 +1346,8 @@ static int bcm_sysport_init_tx_ring(struct bcm_sysport_priv *priv,
 
 	ring->cbs = kcalloc(size, sizeof(struct bcm_sysport_cb), 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;
 	}

-- 
2.9.3

From: Florian Fainelli <f.fainelli@gmail.com>
Date: Thu, 24 Aug 2017 16:01:13 -0700

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 <redacted>
Fixes: 80105befdb4b ("net: systemport: add Broadcom SYSTEMPORT Ethernet MAC driver")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>

Applied and queued up for -stable.