Re: [PATCH 1/5] perf tools kvm: Add missed memory allocation check and free

["Mi, Dapeng" <dapeng1.mi@linux.intel.com>]

On 8/7/2025 7:40 AM, Namhyung Kim wrote:
> On Tue, Aug 05, 2025 at 08:46:29AM +0800, Dapeng Mi wrote:
>> Current code allocates rec_argv[] array, but doesn't check if the
>> allocation is successful and explicitly free the rec_argv[] array.
>>
>> Add them back.
>>
>> Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
>> ---
>>  tools/perf/builtin-kvm.c | 29 +++++++++++++++++++++++------
>>  1 file changed, 23 insertions(+), 6 deletions(-)
>>
>> diff --git a/tools/perf/builtin-kvm.c b/tools/perf/builtin-kvm.c
>> index 7b15b4a705e4..f78a67a199ff 100644
>> --- a/tools/perf/builtin-kvm.c
>> +++ b/tools/perf/builtin-kvm.c
>> @@ -1719,7 +1719,9 @@ kvm_events_record(struct perf_kvm_stat *kvm, int argc, const char **argv)
>>  	set_option_flag(record_options, 0, "transaction", PARSE_OPT_DISABLED);
>>  
>>  	record_usage = kvm_stat_record_usage;
>> -	return cmd_record(i, rec_argv);
>> +	ret = cmd_record(i, rec_argv);
>> +	free(rec_argv);
> Well.. it's not enough just to free rec_argv.  You also need to free all
> items in the rec_argv[].  Probably you want to add more STRDUP_FAIL_EXIT
> when copying the original argv (here and other places).

Oh, yes. Would do. Thanks. 


>
> Thanks,
> Namhyung
>
>
>> +	return ret;
>>  }
>>  
>>  static int
>> @@ -2006,6 +2008,9 @@ static int __cmd_record(const char *file_name, int argc, const char **argv)
>>  
>>  	rec_argc = argc + 2;
>>  	rec_argv = calloc(rec_argc + 1, sizeof(char *));
>> +	if (!rec_argv)
>> +		return -ENOMEM;
>> +
>>  	rec_argv[i++] = strdup("record");
>>  	rec_argv[i++] = strdup("-o");
>>  	rec_argv[i++] = strdup(file_name);
>> @@ -2014,16 +2019,21 @@ static int __cmd_record(const char *file_name, int argc, const char **argv)
>>  
>>  	BUG_ON(i != rec_argc);
>>  
>> -	return cmd_record(i, rec_argv);
>> +	ret = cmd_record(i, rec_argv);
>> +	free(rec_argv);
>> +	return ret;
>>  }
>>  
>>  static int __cmd_report(const char *file_name, int argc, const char **argv)
>>  {
>> -	int rec_argc, i = 0, j;
>> +	int rec_argc, i = 0, j, ret;
>>  	const char **rec_argv;
>>  
>>  	rec_argc = argc + 2;
>>  	rec_argv = calloc(rec_argc + 1, sizeof(char *));
>> +	if (!rec_argv)
>> +		return -ENOMEM;
>> +
>>  	rec_argv[i++] = strdup("report");
>>  	rec_argv[i++] = strdup("-i");
>>  	rec_argv[i++] = strdup(file_name);
>> @@ -2032,17 +2042,22 @@ static int __cmd_report(const char *file_name, int argc, const char **argv)
>>  
>>  	BUG_ON(i != rec_argc);
>>  
>> -	return cmd_report(i, rec_argv);
>> +	ret = cmd_report(i, rec_argv);
>> +	free(rec_argv);
>> +	return ret;
>>  }
>>  
>>  static int
>>  __cmd_buildid_list(const char *file_name, int argc, const char **argv)
>>  {
>> -	int rec_argc, i = 0, j;
>> +	int rec_argc, i = 0, j, ret;
>>  	const char **rec_argv;
>>  
>>  	rec_argc = argc + 2;
>>  	rec_argv = calloc(rec_argc + 1, sizeof(char *));
>> +	if (!rec_argv)
>> +		return -ENOMEM;
>> +
>>  	rec_argv[i++] = strdup("buildid-list");
>>  	rec_argv[i++] = strdup("-i");
>>  	rec_argv[i++] = strdup(file_name);
>> @@ -2051,7 +2066,9 @@ __cmd_buildid_list(const char *file_name, int argc, const char **argv)
>>  
>>  	BUG_ON(i != rec_argc);
>>  
>> -	return cmd_buildid_list(i, rec_argv);
>> +	ret = cmd_buildid_list(i, rec_argv);
>> +	free(rec_argv);
>> +	return ret;
>>  }
>>  
>>  int cmd_kvm(int argc, const char **argv)
>> -- 
>> 2.34.1
>>