The probe function never performs any paltform device allocation, thus error path "undo_platform_dev_alloc" is entirely bogus. It drops the reference count from the platform device being probed. If error path is triggered, this will lead to unbalanced device reference counts and premature release of device resources, thus possible use-after-free when releasing remaining devm-managed resources.
Fixes: f83fca0707c6 ("usb: dwc3: add ST dwc3 glue layer to manage dwc3 HC") Cc: stable@vger.kernel.org Signed-off-by: Krzysztof Kozlowski krzysztof.kozlowski@linaro.org --- drivers/usb/dwc3/dwc3-st.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-)
diff --git a/drivers/usb/dwc3/dwc3-st.c b/drivers/usb/dwc3/dwc3-st.c index 211360eee95a..a9cb04043f08 100644 --- a/drivers/usb/dwc3/dwc3-st.c +++ b/drivers/usb/dwc3/dwc3-st.c @@ -219,10 +219,8 @@ static int st_dwc3_probe(struct platform_device *pdev) dwc3_data->regmap = regmap;
res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "syscfg-reg"); - if (!res) { - ret = -ENXIO; - goto undo_platform_dev_alloc; - } + if (!res) + return -ENXIO;
dwc3_data->syscfg_reg_off = res->start;
@@ -233,8 +231,7 @@ static int st_dwc3_probe(struct platform_device *pdev) devm_reset_control_get_exclusive(dev, "powerdown"); if (IS_ERR(dwc3_data->rstc_pwrdn)) { dev_err(&pdev->dev, "could not get power controller\n"); - ret = PTR_ERR(dwc3_data->rstc_pwrdn); - goto undo_platform_dev_alloc; + return PTR_ERR(dwc3_data->rstc_pwrdn); }
/* Manage PowerDown */ @@ -300,8 +297,6 @@ static int st_dwc3_probe(struct platform_device *pdev) reset_control_assert(dwc3_data->rstc_rst); undo_powerdown: reset_control_assert(dwc3_data->rstc_pwrdn); -undo_platform_dev_alloc: - platform_device_put(pdev); return ret; }