[Spice-devel] [usbredir v2] usbredirhost: avoid access to null pointer

[Pavel Grunt]

On Thu, 2016-08-04 at 13:57 +0200, Victor Toso wrote:
> ERROR() is a wrapper for va_log() which takes usbredirhost* as first
> argument. We can't use it if host == NULL. Changing to fprintf to not
> fail the function silently.
> 
> This was catched by coverity:
>  3. usbredir-0.7.1/usbredirhost/usbredirhost.c:1412: var_deref_model:
>     Passing null pointer "host" to "va_log", which dereferences it.
>  4. usbredir-0.7.1/usbredirhost/usbredirhost.c:163:5: deref_parm:
>     Directly dereferencing parameter "host".
>  #   161|       int n;
>  #   162|
>  #   163|->     if (level > host->verbose) {
>  #   164|           return;
>  #   165|       }
Acked-by: Pavel Grunt <pgrunt at redhat.com>
> ---
>  usbredirhost/usbredirhost.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/usbredirhost/usbredirhost.c b/usbredirhost/usbredirhost.c
> index 3e80677..857e821 100644
> --- a/usbredirhost/usbredirhost.c
> +++ b/usbredirhost/usbredirhost.c
> @@ -1409,7 +1409,7 @@ void usbredirhost_set_buffered_output_size_cb(struct
> usbredirhost *host,
>      usbredirhost_buffered_output_size buffered_output_size_func)
>  {
>      if (!host) {
> -        ERROR("invalid usbredirhost");
> +        fprintf(stderr, "%s: invalid usbredirhost", __func__);
the original code was always prepending "usbredirhost: ", function name is
probably more helpful (__func__ is C99, but I guess it is ok)

Pavel
>          return;
>      }
>