usb: dwc3: keystone: check return value

[ Upstream commit 018047a1dba7636e1f7fdae2cc290a528991d648 ]

Function devm_clk_get() returns an ERR_PTR when it fails. However, in
function kdwc3_probe(), its return value is not checked, which may
result in a bad memory access bug. This patch fixes the bug.

Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/dwc3/dwc3-keystone.c b/drivers/usb/dwc3/dwc3-keystone.c
index 2be268d..03a926e 100644 (file)
--- a/drivers/usb/dwc3/dwc3-keystone.c
+++ b/drivers/usb/dwc3/dwc3-keystone.c
@@ -112,6 +112,10 @@ static int kdwc3_probe(struct platform_device *pdev)
        dev->dma_mask = &kdwc3_dma_mask;
 
        kdwc->clk = devm_clk_get(kdwc->dev, "usb");
+       if (IS_ERR(kdwc->clk)) {
+               dev_err(kdwc->dev, "unable to get usb clock\n");
+               return PTR_ERR(kdwc->clk);
+       }
 
        error = clk_prepare_enable(kdwc->clk);
        if (error < 0) {