[PATCH 4.19 33/95] net: macb: fix use after free on rmmod

[Greg Kroah-Hartman]

From: Tong Zhang <ztong0001@xxxxxxxxx>

[ 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@xxxxxxxxxxxxx>
Signed-off-by: Tong Zhang <ztong0001@xxxxxxxxx>
Acked-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 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 248a8fc45069..f06fddf9919b 100644
--- a/drivers/net/ethernet/cadence/macb_pci.c
+++ b/drivers/net/ethernet/cadence/macb_pci.c
@@ -123,9 +123,9 @@ 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[] = {
-- 
2.33.0