Re: [PATCH 06/31] serial: qcom_geni_serial: fix potential mem leak in qcom_geni_serial_probe()

From: Viresh Kumar
Date: Mon Jan 04 2021 - 02:04:00 EST


On 01-01-21, 16:54, Yangtao Li wrote:
> We should use dev_pm_opp_put_clkname() to free opp table each time
> dev_pm_opp_of_add_table() got error.
>
> Signed-off-by: Yangtao Li <tiny.windzz@xxxxxxxxx>
> ---
> drivers/tty/serial/qcom_geni_serial.c | 10 ++++++----
> 1 file changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
> index 291649f02821..5aada7ebae35 100644
> --- a/drivers/tty/serial/qcom_geni_serial.c
> +++ b/drivers/tty/serial/qcom_geni_serial.c
> @@ -1438,9 +1438,12 @@ static int qcom_geni_serial_probe(struct platform_device *pdev)
> return PTR_ERR(port->se.opp_table);
> /* OPP table is optional */
> ret = dev_pm_opp_of_add_table(&pdev->dev);
> - if (ret && ret != -ENODEV) {
> - dev_err(&pdev->dev, "invalid OPP table in device tree\n");
> - goto put_clkname;
> + if (ret) {
> + dev_pm_opp_put_clkname(port->se.opp_table);
> + if (ret != -ENODEV) {
> + dev_err(&pdev->dev, "invalid OPP table in device tree\n");
> + return ret;
> + }
> }
>
> port->private_data.drv = drv;
> @@ -1482,7 +1485,6 @@ static int qcom_geni_serial_probe(struct platform_device *pdev)
> return 0;
> err:
> dev_pm_opp_of_remove_table(&pdev->dev);
> -put_clkname:
> dev_pm_opp_put_clkname(port->se.opp_table);
> return ret;
> }

Since put_clkname is always done in remove(), I don't think there is
any memleak here. Over that with your patch we will do put_clkname
twice now, once in probe and once in remove. And that is a bug AFAICT.

--
viresh