On 04/01/2016 03:08 PM, zhanghailiang wrote:
> After commit 338d3f, we support 'status' property for filter object.
> The segfault can be triggered by starting qemu with 'status=off' property
> for filter, when the s->incoming_queue is NULL, we reference it directly
> in qemu_net_queue_flush().
>
> Let's check the value of 's->incoming_queue' before calling
> qemu_net_queue_flush().
>
> Signed-off-by: zhanghailiang <zhang.zhanghaili...@huawei.com>
> ---
> net/filter-buffer.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/net/filter-buffer.c b/net/filter-buffer.c
> index cc6bd94..79e2ce3 100644
> --- a/net/filter-buffer.c
> +++ b/net/filter-buffer.c
> @@ -34,7 +34,7 @@ static void filter_buffer_flush(NetFilterState *nf)
> {
> FilterBufferState *s = FILTER_BUFFER(nf);
>
> - if (!qemu_net_queue_flush(s->incoming_queue)) {
> + if (s->incoming_queue && !qemu_net_queue_flush(s->incoming_queue)) {
> /* Unable to empty the queue, purge remaining packets */
> qemu_net_queue_purge(s->incoming_queue, nf->netdev);
> }
We'd better handle this at generic layer and don't let a specific net
filter need to worry about this.
Looks like the issue is we may trigger status_changed() too early (even
before the the filter was initialized).
How about not call status_changed() if the initialization is not done?
