[PATCH] net: gianfar: Add of_node_put() before goto statement

[PATCH] net: gianfar: Add of_node_put() before goto statement

[Sumera Priyadarsini]

Every iteration of for_each_available_child_of_node() decrements
reference count of the previous node, however when control
is transferred from the middle of the loop, as in the case of
a return or break or goto, there is no decrement thus ultimately
resulting in a memory leak.

Fix a potential memory leak in gianfar.c by inserting of_node_put()
before the goto statement.

Issue found with Coccinelle.

Signed-off-by: Sumera Priyadarsini <sylphrenadin@gmail.com>
---
 drivers/net/ethernet/freescale/gianfar.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/freescale/gianfar.c b/drivers/net/ethernet/freescale/gianfar.c
index b513b8c5c3b5..41dd3d0f3452 100644
--- a/drivers/net/ethernet/freescale/gianfar.c
+++ b/drivers/net/ethernet/freescale/gianfar.c
@@ -750,8 +750,10 @@ static int gfar_of_init(struct platform_device *ofdev, struct net_device **pdev)
 				continue;
 
 			err = gfar_parse_group(child, priv, model);
-			if (err)
+			if (err) {
+				of_node_put(child);
 				goto err_grp_init;
+			}
 		}
 	} else { /* SQ_SG_MODE */
 		err = gfar_parse_group(np, priv, model);
-- 
2.17.1

Re: [PATCH] net: gianfar: Add of_node_put() before goto statement

[David Miller]

From: Sumera Priyadarsini <sylphrenadin@gmail.com>
Date: Wed, 19 Aug 2020 00:22:41 +0530

> Every iteration of for_each_available_child_of_node() decrements
> reference count of the previous node, however when control
> is transferred from the middle of the loop, as in the case of
> a return or break or goto, there is no decrement thus ultimately
> resulting in a memory leak.
> 
> Fix a potential memory leak in gianfar.c by inserting of_node_put()
> before the goto statement.
> 
> Issue found with Coccinelle.
> 
> Signed-off-by: Sumera Priyadarsini <sylphrenadin@gmail.com>

These OF iterators are so error prone...

Applied, thanks.