fix audio

(cherry picked from commit c25f93a)
(cherry picked from commit e1328cd)

Author: hyt-hz

trunk/src/app/srs_app_rtc_codec.cpp

@@ -335,6 +335,15 @@ srs_error_t SrsAudioTranscoder::decode_and_resample(SrsAudioFrame *pkt)
     }
 
     char err_buf[AV_ERROR_MAX_STRING_SIZE] = {0};
+
+    if (dec_packet_->data == NULL || dec_packet_->size == 0) {
+        return srs_error_new(
+            ERROR_RTC_INVALID_PARAMS,
+            "dec_pakcet is invalide(%p,%d)",
+            dec_packet_->data, dec_packet_->size
+        );
+    }
+
     int error = avcodec_send_packet(dec_, dec_packet_);
     if (error < 0) {
         return srs_error_new(ERROR_RTC_RTP_MUXER, "submit to dec(%d,%s)", error,