[PATCH v4 6/6] usb: dwc3: qcom: Improve error handling

From: Lee Jones
Date: Wed Jun 12 2019 - 10:31:50 EST


dwc3_qcom_clk_init() is called with of_count_phandle_with_args() as an
argument. If of_count_phandle_with_args() returns an error, the number
of clocks will be a negative value and will lead to undefined behaviour.

Ensure we check for an error before attempting to blindly use the value.

Signed-off-by: Lee Jones <lee.jones@xxxxxxxxxx>
Reviewed-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
---
drivers/usb/dwc3/dwc3-qcom.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c
index 55ba04254e38..e4dac82abd7d 100644
--- a/drivers/usb/dwc3/dwc3-qcom.c
+++ b/drivers/usb/dwc3/dwc3-qcom.c
@@ -409,6 +409,9 @@ static int dwc3_qcom_clk_init(struct dwc3_qcom *qcom, int count)
if (!np || !count)
return 0;

+ if (count < 0)
+ return count;
+
qcom->num_clocks = count;

qcom->clks = devm_kcalloc(dev, qcom->num_clocks,
--
2.17.1