[PATCH] tools/power turbostat: close file after use

[PATCH] tools/power turbostat: close file after use

[Tom Rix]

The cppcheck reports this issue
turbostat.c:2039]: (error) Resource leak: fp

When the fscanf fails an error is returned without closing fp.
Move the fclose so even if the fscanf fails, the file will be closed.

Fixes: eae97e053fe3 ("tools/power turbostat: Support thermal throttle count print")
Signed-off-by: Tom Rix <trix@redhat.com>
---
 tools/power/x86/turbostat/turbostat.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c
index ede31a4287a0..2e9a751af260 100644
--- a/tools/power/x86/turbostat/turbostat.c
+++ b/tools/power/x86/turbostat/turbostat.c
@@ -2035,9 +2035,9 @@ int get_core_throt_cnt(int cpu, unsigned long long *cnt)
 	if (!fp)
 		return -1;
 	ret = fscanf(fp, "%lld", &tmp);
+	fclose(fp);
 	if (ret != 1)
 		return -1;
-	fclose(fp);
 	*cnt = tmp;
 
 	return 0;
-- 
2.27.0

Re: [PATCH] tools/power turbostat: close file after use

[Chen Yu]

On Sat, Apr 30, 2022 at 10:15:57AM -0400, Tom Rix wrote:
> The cppcheck reports this issue
> turbostat.c:2039]: (error) Resource leak: fp
> 
> When the fscanf fails an error is returned without closing fp.
> Move the fclose so even if the fscanf fails, the file will be closed.
> 
> Fixes: eae97e053fe3 ("tools/power turbostat: Support thermal throttle count print")
> Signed-off-by: Tom Rix <trix@redhat.com>
> ---
>  tools/power/x86/turbostat/turbostat.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c
> index ede31a4287a0..2e9a751af260 100644
> --- a/tools/power/x86/turbostat/turbostat.c
> +++ b/tools/power/x86/turbostat/turbostat.c
> @@ -2035,9 +2035,9 @@ int get_core_throt_cnt(int cpu, unsigned long long *cnt)
>  	if (!fp)
>  		return -1;
>  	ret = fscanf(fp, "%lld", &tmp);
> +	fclose(fp);
>  	if (ret != 1)
>  		return -1;
> -	fclose(fp);
>  	*cnt = tmp;
>  
>  	return 0;
> --
Thank you Tom, and Colin has proposed a fix here:
https://lore.kernel.org/lkml/20220426131607.1520483-1-colin.i.king@gmail.com/

thanks,
Chenyu

Re: [PATCH] tools/power turbostat: close file after use

[Tom Rix]

On 4/30/22 7:19 AM, Chen Yu wrote:
> On Sat, Apr 30, 2022 at 10:15:57AM -0400, Tom Rix wrote:
>> The cppcheck reports this issue
>> turbostat.c:2039]: (error) Resource leak: fp
>>
>> When the fscanf fails an error is returned without closing fp.
>> Move the fclose so even if the fscanf fails, the file will be closed.
>>
>> Fixes: eae97e053fe3 ("tools/power turbostat: Support thermal throttle count print")
>> Signed-off-by: Tom Rix <trix@redhat.com>
>> ---
>>   tools/power/x86/turbostat/turbostat.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c
>> index ede31a4287a0..2e9a751af260 100644
>> --- a/tools/power/x86/turbostat/turbostat.c
>> +++ b/tools/power/x86/turbostat/turbostat.c
>> @@ -2035,9 +2035,9 @@ int get_core_throt_cnt(int cpu, unsigned long long *cnt)
>>   	if (!fp)
>>   		return -1;
>>   	ret = fscanf(fp, "%lld", &tmp);
>> +	fclose(fp);
>>   	if (ret != 1)
>>   		return -1;
>> -	fclose(fp);
>>   	*cnt = tmp;
>>   
>>   	return 0;
>> --
> Thank you Tom, and Colin has proposed a fix here:
> https://lore.kernel.org/lkml/20220426131607.1520483-1-colin.i.king@gmail.com/

Obviously I approve of Colin's fix :)

If it is not too much trouble, please add

Reviewed-by: Tom Rix <trix@redhat.com>

If it is already on its way to linux-next, don't worry about it.

Thanks,

Tom

>
> thanks,
> Chenyu
>