Re: [PATCH] perf kmem: Fix memory leak in compact_gfp_flags()

[Yunfeng Ye]

On 2019/10/16 21:09, Arnaldo Carvalho de Melo wrote:
> Em Wed, Oct 16, 2019 at 10:04:03AM -0300, Arnaldo Carvalho de Melo escreveu:
>> Em Wed, Oct 16, 2019 at 04:38:45PM +0800, Yunfeng Ye escreveu:
>>> The memory @orig_flags is allocated by strdup(), it is freed on the
>>> normal path, but leak to free on the error path.
>>
>> Are you using some tool to find out these problems? Or is it just visual
>> inspection?
> 
By a static code anaylsis tool which not an open source tool. thanks.

> Anyway, applied after adding this to the commit log message:
> 
> Fixes: 0e11115644b3 ("perf kmem: Print gfp flags in human readable string")
> 
ok, thanks.

> - Arnaldo
>  
>> - Arnaldo
>>  
>>> Fix this by adding free(orig_flags) on the error path.
>>>
>>> Signed-off-by: Yunfeng Ye <yeyunfeng@xxxxxxxxxx>
>>> ---
>>>  tools/perf/builtin-kmem.c | 1 +
>>>  1 file changed, 1 insertion(+)
>>>
>>> diff --git a/tools/perf/builtin-kmem.c b/tools/perf/builtin-kmem.c
>>> index 1e61e353f579..9661671cc26e 100644
>>> --- a/tools/perf/builtin-kmem.c
>>> +++ b/tools/perf/builtin-kmem.c
>>> @@ -691,6 +691,7 @@ static char *compact_gfp_flags(char *gfp_flags)
>>>  			new = realloc(new_flags, len + strlen(cpt) + 2);
>>>  			if (new == NULL) {
>>>  				free(new_flags);
>>> +				free(orig_flags);
>>>  				return NULL;
>>>  			}
>>>
>>> -- 
>>> 2.7.4.3
>>
>> -- 
>>
>> - Arnaldo
>