Re: [PATCH] clocksource/drivers: Fix memory leak in ttc_setup_clockevent

[Michal Simek]

On 22. 10. 19 10:26, Markus Elfring wrote:
>> In the impelementation of ttc_setup_clockevent() the allocated memory
>> for ttcce should be released if clk_notifier_register() fails.
> 
> * Please avoid the copying of typos from previous change descriptions.
> 
> * Under which circumstances will an âimperative moodâ matter for you here?
>   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/submitting-patches.rst?id=7d194c2100ad2a6dded545887d02754948ca5241#n151
> 
> 
>> +++ b/drivers/clocksource/timer-cadence-ttc.c
>> @@ -424,6 +424,7 @@ static int __init ttc_setup_clockevent(struct clk *clk,
>>  				    &ttcce->ttc.clk_rate_change_nb);
>>  	if (err) {
>>  		pr_warn("Unable to register clock notifier.\n");
>> +		kfree(ttcce);
>>  		return err;
>>  	}
> 
> This addition looks correct.
> But I would prefer to move such exception handling code to the end of
> this function implementation so that duplicate source code will be reduced.
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/coding-style.rst?id=7d194c2100ad2a6dded545887d02754948ca5241#n450

Just a note. Maybe you should also consider to fix this error path in
ttc_setup_clocksource() when notifier also can fail that there is no
need to continue with code execution.

Thanks,
Michal