[PATCH net] net: phylink: put link_gpio if phylink_create fails

[Christian Marangi]

In phylink_create() if phylink_register_sfp() returns an error, link_gpio
obtained by phylink_parse_fixedlink() is never released. While this is a
very unlikely scenario, it's worth to fix/handle this.

This was present from the very first implementation of phylink but got
relevant only with the introduction of ce0aa27ff3f6 ("sfp: add sfp-bus to
bridge between network devices and sfp cages") where additional function
were added after phylink_parse_fixedlink() making the release of link_gpio
needed if such additional function errored out.

While at it, restructure the exit condition of phylink_create() with the
goto pattern to reduce code duplication on handling error conditions.

Fixes: ce0aa27ff3f6 ("sfp: add sfp-bus to bridge between network devices and sfp cages")
Signed-off-by: Christian Marangi <ansuelsmth@xxxxxxxxx>
---
 drivers/net/phy/phylink.c | 29 +++++++++++++++--------------
 1 file changed, 15 insertions(+), 14 deletions(-)

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index 59dfe35afa54..f40acc0d4133 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -1874,8 +1874,8 @@ struct phylink *phylink_create(struct phylink_config *config,
 	} else if (config->type == PHYLINK_DEV) {
 		pl->dev = config->dev;
 	} else {
-		kfree(pl);
-		return ERR_PTR(-EINVAL);
+		ret = -EINVAL;
+		goto free_pl;
 	}
 
 	pl->mac_supports_eee_ops = phylink_mac_implements_lpi(mac_ops);
@@ -1908,28 +1908,29 @@ struct phylink *phylink_create(struct phylink_config *config,
 	phylink_validate(pl, pl->supported, &pl->link_config);
 
 	ret = phylink_parse_mode(pl, fwnode);
-	if (ret < 0) {
-		kfree(pl);
-		return ERR_PTR(ret);
-	}
+	if (ret < 0)
+		goto free_pl;
 
 	if (pl->cfg_link_an_mode == MLO_AN_FIXED) {
 		ret = phylink_parse_fixedlink(pl, fwnode);
-		if (ret < 0) {
-			kfree(pl);
-			return ERR_PTR(ret);
-		}
+		if (ret < 0)
+			goto release_link_gpio;
 	}
 
 	pl->req_link_an_mode = pl->cfg_link_an_mode;
 
 	ret = phylink_register_sfp(pl, fwnode);
-	if (ret < 0) {
-		kfree(pl);
-		return ERR_PTR(ret);
-	}
+	if (ret < 0)
+		goto release_link_gpio;
 
 	return pl;
+
+release_link_gpio:
+	if (pl->link_gpio)
+		gpiod_put(pl->link_gpio);
+free_pl:
+	kfree(pl);
+	return ERR_PTR(ret);
 }
 EXPORT_SYMBOL_GPL(phylink_create);
 
-- 
2.53.0