Re: [Qemu-devel] [PATCH v2 2/3] migration: fix memory leak when updating tls-creds and tls-hostname

[Peter Xu <peterx@redhat.com>]

On Fri, Jan 11, 2019 at 02:37:31PM +0800, guangrong.xiao@gmail.com wrote:
> From: Xiao Guangrong <xiaoguangrong@tencent.com>
> 
> If we update parameter, tls-creds and tls-hostname, these string
> values are duplicated to local variables in migrate_params_test_apply()
> by using g_strdup(), however these new allocated memory are missed to
> be freed
> 
> Actually, they are not used to check anything, we can directly skip
> them
> 
> Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
> ---
>  migration/migration.c | 10 ----------
>  1 file changed, 10 deletions(-)
> 
> diff --git a/migration/migration.c b/migration/migration.c
> index a82d594f29..fb39d7bec1 100644
> --- a/migration/migration.c
> +++ b/migration/migration.c
> @@ -1145,16 +1145,6 @@ static void migrate_params_test_apply(MigrateSetParameters *params,
>          dest->cpu_throttle_increment = params->cpu_throttle_increment;
>      }
>  
> -    if (params->has_tls_creds) {
> -        assert(params->tls_creds->type == QTYPE_QSTRING);
> -        dest->tls_creds = g_strdup(params->tls_creds->u.s);
> -    }
> -
> -    if (params->has_tls_hostname) {
> -        assert(params->tls_hostname->type == QTYPE_QSTRING);
> -        dest->tls_hostname = g_strdup(params->tls_hostname->u.s);
> -    }
> -

Hi, Guangrong,

The memleak seems to be correct here but before that I'm even a bit
confused on why we need to copy the whole parameter list here instead
of checking against a MigrateSetParameters* in migrate_params_check().
Could anyone shed some light?  CC Markus too.

Thanks,

>      if (params->has_max_bandwidth) {
>          dest->max_bandwidth = params->max_bandwidth;
>      }
> -- 
> 2.14.5
> 

Regards,

-- 
Peter Xu