[PATCH] net: via-rhine: net: Fix a resource leak in rhine_init()

[Jia-Ju Bai <baijiaju1990@gmail.com>]

When platform_driver_register() fails, pci_unregister_driver() is not
called to release the resource allocated by pci_register_driver().

To fix this bug, error handling code for platform_driver_register() and
pci_register_driver() is separately implemented.

This bug is found by a runtime fuzzing tool named FIZZER written by us.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
---
 drivers/net/ethernet/via/via-rhine.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/via/via-rhine.c b/drivers/net/ethernet/via/via-rhine.c
index 33949248c829..eb74e5a03aac 100644
--- a/drivers/net/ethernet/via/via-rhine.c
+++ b/drivers/net/ethernet/via/via-rhine.c
@@ -2633,10 +2633,15 @@ static int __init rhine_init(void)
 		pr_info("avoid_D3 set\n");
 
 	ret_pci = pci_register_driver(&rhine_driver_pci);
-	ret_platform = platform_driver_register(&rhine_driver_platform);
-	if ((ret_pci < 0) && (ret_platform < 0))
+	if (ret_pci)
 		return ret_pci;
 
+	ret_platform = platform_driver_register(&rhine_driver_platform);
+	if (ret_platform) {
+		pci_unregister_driver(&rhine_driver_pci);
+		return ret_platform;
+	}
+
 	return 0;
 }
 
-- 
2.17.0