[PATCH] usb: host: fotg2: Fix potential NULL dereference

Linus Walleij linus.walleij at linaro.org
Tue Sep 18 16:25:06 PDT 2018


There is code in the .remove() hook to handle the drvdata
being NULL, for good reasons: it is never set, so it will
always be NULL. As I moved code around, static checkers
start complaining.

Instead of this, make sure to always set it on successful
probe so we can always dereference it on the remove path.

Use the platform_device_[set|get]_drvdata() since this is
a platform device.

Fixes: ffa8a31b5b3b ("usb: host: fotg2: add silicon clock handling")
Reported-by: Dan Carpenter <dan.carpenter at oracle.com>
Cc: Dan Carpenter <dan.carpenter at oracle.com>
Signed-off-by: Linus Walleij <linus.walleij at linaro.org>
---
 drivers/usb/host/fotg210-hcd.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/host/fotg210-hcd.c b/drivers/usb/host/fotg210-hcd.c
index 058ff82ea789..bbcc68179bfc 100644
--- a/drivers/usb/host/fotg210-hcd.c
+++ b/drivers/usb/host/fotg210-hcd.c
@@ -5636,6 +5636,7 @@ static int fotg210_hcd_probe(struct platform_device *pdev)
 		goto failed_dis_clk;
 	}
 	device_wakeup_enable(hcd->self.controller);
+	platform_set_drvdata(pdev, hcd);
 
 	return retval;
 
@@ -5656,16 +5657,12 @@ static int fotg210_hcd_probe(struct platform_device *pdev)
  */
 static int fotg210_hcd_remove(struct platform_device *pdev)
 {
-	struct device *dev = &pdev->dev;
-	struct usb_hcd *hcd = dev_get_drvdata(dev);
+	struct usb_hcd *hcd = platform_get_drvdata(pdev);
 	struct fotg210_hcd *fotg210 = hcd_to_fotg210(hcd);
 
 	if (!IS_ERR(fotg210->pclk))
 		clk_disable_unprepare(fotg210->pclk);
 
-	if (!hcd)
-		return 0;
-
 	usb_remove_hcd(hcd);
 	usb_put_hcd(hcd);
 
-- 
2.17.1




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