From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Dan Carpenter <dan.carpenter@oracle.com>
Subject: [PATCH 5.4 15/92] staging: rtl8192e: Fix use after free in _rtl92e_pci_disconnect()
Date:   Mon, 29 Nov 2021 19:17:44 +0100
Message-Id: <20211129181707.929598147@linuxfoundation.org>
In-Reply-To: <20211129181707.392764191@linuxfoundation.org>
References: <20211129181707.392764191@linuxfoundation.org>
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From: Dan Carpenter <dan.carpenter@oracle.com>

commit b535917c51acc97fb0761b1edec85f1f3d02bda4 upstream.

The free_rtllib() function frees the "dev" pointer so there is use
after free on the next line.  Re-arrange things to avoid that.

Fixes: 66898177e7e5 ("staging: rtl8192e: Fix unload/reload problem")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20211117072016.GA5237@kili
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/staging/rtl8192e/rtl8192e/rtl_core.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/staging/rtl8192e/rtl8192e/rtl_core.c
+++ b/drivers/staging/rtl8192e/rtl8192e/rtl_core.c
@@ -2559,13 +2559,14 @@ static void _rtl92e_pci_disconnect(struc
 			free_irq(dev->irq, dev);
 			priv->irq = 0;
 		}
-		free_rtllib(dev);
 
 		if (dev->mem_start != 0) {
 			iounmap((void __iomem *)dev->mem_start);
 			release_mem_region(pci_resource_start(pdev, 1),
 					pci_resource_len(pdev, 1));
 		}
+
+		free_rtllib(dev);
 	} else {
 		priv = rtllib_priv(dev);
 	}