[PATCH] tty: serial: samsung_tty: Fix clk resource leak issue

[Krzysztof Kozlowski]

On 07/11/2022 08:17, Greg KH wrote:
> On Mon, Nov 07, 2022 at 02:21:20PM +0800, Xiu Jianfeng wrote:
>> In the s3c24xx_serial_get_options(), calling clk_get() without clk_put()
>> will cause clk resource leak issue, this patch fixes it.
>>
>> Fixes: b497549a035c ("[ARM] S3C24XX: Split serial driver into core and per-cpu drivers")
>> Signed-off-by: Xiu Jianfeng <xiujianfeng at huawei.com>
>> ---
>>  drivers/tty/serial/samsung_tty.c | 5 +++--
>>  1 file changed, 3 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/tty/serial/samsung_tty.c b/drivers/tty/serial/samsung_tty.c
>> index 77d1363029f5..8a3bb9832172 100644
>> --- a/drivers/tty/serial/samsung_tty.c
>> +++ b/drivers/tty/serial/samsung_tty.c
>> @@ -2529,9 +2529,10 @@ s3c24xx_serial_get_options(struct uart_port *port, int *baud,
>>  		sprintf(clk_name, "clk_uart_baud%d", clk_sel);
>>  
>>  		clk = clk_get(port->dev, clk_name);
>> -		if (!IS_ERR(clk))
>> +		if (!IS_ERR(clk)) {
>>  			rate = clk_get_rate(clk);
>> -		else
>> +			clk_put(clk);
>> +		} else
> 
> How was this tested?

The driver has such potential missing clk_put in few other places as
well: here on success path and few error paths after calling
s3c24xx_serial_enable_baudclk(). Yet I am concerned that none of these
paths were actually tested...

Best regards,
Krzysztof