[PATCH] net: ethernet: mediatek: fix refcount leak in mtk_probe()

[Wentao Liang]

If mtk_sgmii_init() fails after successfully creating some PCS
instances, it returns an error without cleaning up the partially
created ones.  mtk_pcs_lynxi_create() increments the fwnode
refcount for each PCS it creates, but this refcount is never
released because mtk_probe() uses a plain "return err" instead of
a goto to the err_destroy_sgmii label.  This leaks both the PCS
devices and their fwnode references.

Fix the leak by jumping to the existing err_destroy_sgmii path
which calls mtk_sgmii_destroy() to safely release all allocated
resources.

Cc: stable at vger.kernel.org
Fixes: 9ffee4a8276c ("net: ethernet: mediatek: Extend SGMII related functions")
Signed-off-by: Wentao Liang <vulab at iscas.ac.cn>
---
 drivers/net/ethernet/mediatek/mtk_eth_soc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
index 8d225bc9f063..0f185462cf85 100644
--- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c
+++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c
@@ -5169,7 +5169,7 @@ static int mtk_probe(struct platform_device *pdev)
 		err = mtk_sgmii_init(eth);
 
 		if (err)
-			return err;
+			goto err_destroy_sgmii;
 	}
 
 	if (eth->soc->required_pctl) {
-- 
2.34.1