From 31f4303bdc82b6ce564d0c042416cded30410243 Mon Sep 17 00:00:00 2001
From: Pavel Belous <pbelous@marvell.com>
Date: Fri, 14 Feb 2020 18:44:56 +0300
Subject: [PATCH] net: atlantic: fix potential error handling

commit 380ec5b9af7f0d57dbf6ac067fd9f33cff2fef71 upstream.

Code inspection found that in case of mapping error we do return current
'ret' value. But beside error, it is used to count number of descriptors
allocated for the packet. In that case map_skb function could return '1'.

Changing it to return zero (number of mapped descriptors for skb)

Fixes: 018423e90bee ("net: ethernet: aquantia: Add ring support code")
Signed-off-by: Pavel Belous <pbelous@marvell.com>
Signed-off-by: Igor Russkikh <irusskikh@marvell.com>
Signed-off-by: Dmitry Bogdanov <dbogdanov@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_nic.c b/drivers/net/ethernet/aquantia/atlantic/aq_nic.c
index 006d92ca7f84..6fa4bbebf5dc 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_nic.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_nic.c
@@ -453,8 +453,10 @@ static unsigned int aq_nic_map_skb(struct aq_nic_s *self,
 				     dx_buff->len,
 				     DMA_TO_DEVICE);
 
-	if (unlikely(dma_mapping_error(aq_nic_get_dev(self), dx_buff->pa)))
+	if (unlikely(dma_mapping_error(aq_nic_get_dev(self), dx_buff->pa))) {
+		ret = 0;
 		goto exit;
+	}
 
 	first = dx_buff;
 	dx_buff->len_pkt = skb->len;
-- 
2.7.4