mpegtsmux: Avoid crash when best pad gets flushed

The 'best' pad might receive a flush event between us picking it and us
popping the buffer. In this case, the buffer will be missing.

Similar to https://gitlab.freedesktop.org/gstreamer/gst-plugins-good/-/merge_requests/711

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/1042>

diff --git a/subprojects/gst-plugins-bad/gst/mpegtsmux/gstbasetsmux.c b/subprojects/gst-plugins-bad/gst/mpegtsmux/gstbasetsmux.c
index e312ff0..844a4ea 100644 (file)
--- a/subprojects/gst-plugins-bad/gst/mpegtsmux/gstbasetsmux.c
+++ b/subprojects/gst-plugins-bad/gst/mpegtsmux/gstbasetsmux.c
@@ -2294,6 +2294,10 @@ gst_base_ts_mux_aggregate (GstAggregator * agg, gboolean timeout)
     GstBuffer *buffer;
 
     buffer = gst_aggregator_pad_pop_buffer (GST_AGGREGATOR_PAD (best));
+    if (!buffer) {
+      /* We might have gotten a flush event after we picked the pad */
+      goto done;
+    }
 
     ret =
         gst_base_ts_mux_aggregate_buffer (GST_BASE_TS_MUX (agg),