From 4ad6f2d23b0f6ac0d3e5f3102a4256d1c86c90f5 Mon Sep 17 00:00:00 2001
From: Tong Zhang <ztong0001@gmail.com>
Date: Wed, 8 Sep 2021 12:02:32 -0700
Subject: [PATCH] net: macb: fix use after free on rmmod
Git-commit: d82d5303c4c539db86588ffb5dc5b26c3f1513e8
Patch-mainline: v5.15-rc2
References: stable-5.14.9

[ Upstream commit d82d5303c4c539db86588ffb5dc5b26c3f1513e8 ]

plat_dev->dev->platform_data is released by platform_device_unregister(),
use of pclk and hclk is a use-after-free. Since device unregister won't
need a clk device we adjust the function call sequence to fix this issue.

[   31.261225] BUG: KASAN: use-after-free in macb_remove+0x77/0xc6 [macb_pci]
[   31.275563] Freed by task 306:
[   30.276782]  platform_device_release+0x25/0x80

Suggested-by: Nicolas Ferre <Nicolas.Ferre@microchip.com>
Signed-off-by: Tong Zhang <ztong0001@gmail.com>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/net/ethernet/cadence/macb_pci.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/cadence/macb_pci.c b/drivers/net/ethernet/cadence/macb_pci.c
index 8b7b59908a1a..f66d22de5168 100644
--- a/drivers/net/ethernet/cadence/macb_pci.c
+++ b/drivers/net/ethernet/cadence/macb_pci.c
@@ -111,9 +111,9 @@ static void macb_remove(struct pci_dev *pdev)
 	struct platform_device *plat_dev = pci_get_drvdata(pdev);
 	struct macb_platform_data *plat_data = dev_get_platdata(&plat_dev->dev);
 
-	platform_device_unregister(plat_dev);
 	clk_unregister(plat_data->pclk);
 	clk_unregister(plat_data->hclk);
+	platform_device_unregister(plat_dev);
 }
 
 static const struct pci_device_id dev_id_table[] = {
-- 
2.26.2