>
> On Fri, Sep 01, 2017 at 04:05:25PM +0100, Frediano Ziglio wrote:
> > Is possible to have a leak processing update commands if
> > the update command is synchronous and the rectangle list
> > is empty. Note that Qemu always pass an empty list.
> >
> > If the list is empty display_channel_update fill the list.
> > This is used to send back the list in case of asynchronous
> > requests. But in handle_dev_update_async (the callback that
> > handle the asynchronous case) the list is correctly freed.
> >
> > This was discovered by accident looking at the code.
> >
> > Reproduced with a Windows recording file using GCC address
> > sanitizer and this patch to spice-server-replay:
> >
> > --- a/server/red-replay-qxl.c
> > +++ b/server/red-replay-qxl.c
> > @@ -1280,7 +1280,10 @@ static void replay_handle_dev_input(QXLWorker
> > *worker, SpiceReplay *replay,
> > replay->created_primary = FALSE;
> > worker->destroy_surfaces(worker);
> > break;
> > - case RED_WORKER_MESSAGE_UPDATE:
> > + case RED_WORKER_MESSAGE_UPDATE: {
> > + QXLRect update = { 0, 0, 100, 100 };
> > + worker->update_area(worker, 0, &update, NULL, 0, 0);
> > + } break;
> > // XXX do anything? we record the correct bitmaps already.
> > case RED_WORKER_MESSAGE_DISPLAY_CONNECT:
> > // we want to ignore this one - it is sent on client connection,
> > we
>
> NB: inline patches in commit logs confuse git am :-/
>
> >
> > Signed-off-by: Frediano Ziglio <fziglio@xxxxxxxxxx>
> > ---
> > server/red-worker.c | 6 +++++-
> > 1 file changed, 5 insertions(+), 1 deletion(-)
> >
> > diff --git a/server/red-worker.c b/server/red-worker.c
> > index 4d8566be..594dec55 100644
> > --- a/server/red-worker.c
> > +++ b/server/red-worker.c
> > @@ -437,13 +437,17 @@ static void handle_dev_update(void *opaque, void
> > *payload)
> > {
> > RedWorker *worker = opaque;
> > RedWorkerMessageUpdate *msg = payload;
> > + QXLRect *qxl_dirty_rects = msg->qxl_dirty_rects;
> >
> > spice_return_if_fail(worker->running);
> >
> > flush_display_commands(worker);
> > display_channel_update(worker->display_channel,
> > msg->surface_id, msg->qxl_area,
> > msg->clear_dirty_region,
> > - &msg->qxl_dirty_rects, &msg->num_dirty_rects);
> > + &qxl_dirty_rects, &msg->num_dirty_rects);
> > + if (msg->qxl_dirty_rects != qxl_dirty_rects) {
> > + free(qxl_dirty_rects);
> > + }
>
> Given that the caller (red_qxl_update_area) does not care about the
> msg->qxl_dirty_rects/msg->num_dirty_rects, I guess you could always pass
> NULL, and update display_channel_update accordingly. Maybe it would even
> be enough to call display_channel_draw() here instead?
>
> Christophe
>
In case of async message (used by Linux drivers) display_channel_draw
fills the rectangle list and the list is passed back to Qemu.
Is not an output variable, is also an input one we need the
value passed by red_qxl_update_area.
Maybe I didn't get what you suggested.
Frediano
_______________________________________________
Spice-devel mailing list
Spice-devel@xxxxxxxxxxxxxxxxxxxxx
https://lists.freedesktop.org/mailman/listinfo/spice-devel