Re: [Qemu-devel] [PATCH 1/2] vnc: fix segfault due to failed handshake

["Andreas Färber" <afaerber@suse.de>]

Am 14.10.2012 15:08, schrieb Tim Hardeck:
> When the VNC server disconnects due to a failed handshake we don't have
> vs->bh allocated yet.
> 
> Check for this case and don't delete it.
> 
> Signed-off-by: Tim Hardeck <thardeck@suse.de>
> ---
>  ui/vnc.c |    4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/ui/vnc.c b/ui/vnc.c
> index 01b2daf..656895a 100644
> --- a/ui/vnc.c
> +++ b/ui/vnc.c
> @@ -1055,7 +1055,9 @@ static void vnc_disconnect_finish(VncState *vs)
>      vnc_unlock_output(vs);
>  
>      qemu_mutex_destroy(&vs->output_mutex);
> -    qemu_bh_delete(vs->bh);
> +    if (vs->bh != NULL) {
> +        qemu_bh_delete(vs->bh);
> +    }
>      buffer_free(&vs->jobs_buffer);
>  
>      for (i = 0; i < VNC_STAT_ROWS; ++i) {

qemu_bh_delete() is not checking for a NULL argument, therefore this fix
looks good to me,

Acked-by: Andreas Färber <afaerber@suse.de>

Adding some CCs.

As a followup it might be a good idea to either assert or ignore a NULL
argument in qemu_bh_delete().

Regards,
Andreas

-- 
SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany
GF: Jeff Hawn, Jennifer Guild, Felix Imendörffer; HRB 16746 AG Nürnberg