Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org,
        Nicolas Ferre <Nicolas.Ferre@microchip.com>,
        Tong Zhang <ztong0001@gmail.com>,
        Nicolas Ferre <nicolas.ferre@microchip.com>,
        "David S. Miller" <davem@davemloft.net>,
        Sasha Levin <sashal@kernel.org>
Subject: [PATCH 4.19 33/95] net: macb: fix use after free on rmmod
Date:   Mon,  4 Oct 2021 14:52:03 +0200
Message-Id: <20211004125034.645427784@linuxfoundation.org>
In-Reply-To: <20211004125033.572932188@linuxfoundation.org>
References: <20211004125033.572932188@linuxfoundation.org>
User-Agent: quilt/0.66
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Tong Zhang <ztong0001@gmail.com>

[ 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>
---
 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