[PATCH 1/2] gatppp: Check ppp instance before unref it

[Marcel Holtmann]

Hi Zhenhua,

> ---
>  gatchat/gatppp.c |    3 +++
>  1 files changed, 3 insertions(+), 0 deletions(-)
> 
> diff --git a/gatchat/gatppp.c b/gatchat/gatppp.c
> index 1d41ded..d9b1627 100644
> --- a/gatchat/gatppp.c
> +++ b/gatchat/gatppp.c
> @@ -446,6 +446,9 @@ void g_at_ppp_unref(GAtPPP *ppp)
>  {
>  	gboolean is_zero;
>  
> +	if (ppp == NULL)
> +		return;
> +
>  	is_zero = g_atomic_int_dec_and_test(&ppp->ref_count);
>  
>  	if (is_zero == FALSE)

since we have been safe-guarding this in other unref functions as well,
I also applied this patch.

In general the calling code is doing something wrong here if it tries to
unref a NULL pointer.

Regards

Marcel