fix: dashcamd OMX crash on restart, add dashcam status indicator

- Reset OMX subsystem (Deinit/Init) on dashcamd startup to clear stale
  encoder state from previous unclean exits
- Validate OMX output buffers before memcpy to prevent segfault
- Validate VisionBuf frame data before encoding
- Add dashcam row to status window showing recording state and disk usage

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

selfdrive/clearpilot/dashcamd.cc

@@ -118,6 +118,10 @@ static std::string srt_time(int seconds) {
 int main(int argc, char *argv[]) {
   setpriority(PRIO_PROCESS, 0, -10);
 
+  // Reset OMX subsystem — clears any stale encoder state from previous unclean exit
+  OMX_Deinit();
+  OMX_Init();
+
   // Ensure base output directory exists
   mkdir(VIDEOS_BASE.c_str(), 0755);
 
@@ -341,6 +345,16 @@ int main(int argc, char *argv[]) {
 
     uint64_t ts = nanos_since_boot() - segment_start_ts;
 
+    // Validate buffer before encoding
+    if (buf->y == nullptr || buf->uv == nullptr || buf->width == 0 || buf->height == 0) {
+      LOGE("dashcamd: invalid frame buf y=%p uv=%p %zux%zu, skipping", buf->y, buf->uv, buf->width, buf->height);
+      continue;
+    }
+
+    if (frame_count == 0) {
+      LOGW("dashcamd: first encode w=%d h=%d stride=%d buf_y=%p buf_uv=%p", width, height, y_stride, buf->y, buf->uv);
+    }
+
     // Feed NV12 frame directly to OMX encoder
     encoder->encode_frame_nv12(buf->y, y_stride, buf->uv, uv_stride, width, height, ts);
     frame_count++;

selfdrive/frogpilot/screenrecorder/omx_encoder.cc

@@ -446,6 +446,12 @@ OmxEncoder::OmxEncoder(const char* path, int width, int height, int fps, int bit
 
 void OmxEncoder::handle_out_buf(OmxEncoder *e, OMX_BUFFERHEADERTYPE *out_buf) {
   int err;
+
+  if (out_buf->pBuffer == nullptr || out_buf->nFilledLen == 0) {
+    OMX_CHECK(OMX_FillThisBuffer(e->handle, out_buf));
+    return;
+  }
+
   uint8_t *buf_data = out_buf->pBuffer + out_buf->nOffset;
 
   if (out_buf->nFlags & OMX_BUFFERFLAG_CODECCONFIG) {
@@ -613,6 +619,7 @@ int OmxEncoder::encode_frame_nv12(const uint8_t *y_ptr, int y_stride, const uint
     handle_out_buf(this, out_buf);
   }
 
+
   this->dirty = true;
   this->counter++;
 

selfdrive/ui/qt/window.cc

@@ -263,6 +263,11 @@ static StatusWindow::StatusData collectStatus() {
   // Telemetry
   d.telemetry = readFile("/data/params/d/TelemetryEnabled");
 
+  // Dashcam
+  QString dashcam_pid = shellCmd("pgrep -x dashcamd");
+  d.dashcam_status = dashcam_pid.isEmpty() ? "stopped" : "recording";
+  d.dashcam_size = shellCmd("du -sh /data/media/0/videos 2>/dev/null | awk '{print $1}'");
+
   // Panda: checked on UI thread in applyResults() via scene.pandaType
 
   return d;
@@ -305,6 +310,7 @@ StatusWindow::StatusWindow(QWidget *parent) : QFrame(parent) {
   vpn_label = makeRow("VPN");
   gps_label = makeRow("GPS");
   telemetry_label = makeRow("Telemetry");
+  dashcam_label = makeRow("Dashcam");
 
   layout->addStretch();
 
@@ -376,6 +382,16 @@ void StatusWindow::applyResults() {
     telemetry_label->setText("Disabled");
     telemetry_label->setStyleSheet("color: grey; font-size: 38px;");
   }
+
+  if (d.dashcam_status == "recording") {
+    QString text = "Recording";
+    if (!d.dashcam_size.isEmpty()) text += " (" + d.dashcam_size + ")";
+    dashcam_label->setText(text);
+    dashcam_label->setStyleSheet("color: #17c44d; font-size: 38px;");
+  } else {
+    dashcam_label->setText("Stopped");
+    dashcam_label->setStyleSheet("color: #ff4444; font-size: 38px;");
+  }
 }
 
 void StatusWindow::mousePressEvent(QMouseEvent *e) {

selfdrive/ui/qt/window.h

@@ -20,6 +20,7 @@ public:
   struct StatusData {
     QString time, storage, ram, load, temp, fan, ip, wifi;
     QString vpn_status, vpn_ip, gps, telemetry;
+    QString dashcam_status, dashcam_size;
     float temp_c = 0;
   };
 
@@ -49,6 +50,7 @@ private:
   QLabel *gps_label;
   QLabel *time_label;
   QLabel *telemetry_label;
+  QLabel *dashcam_label;
   QLabel *panda_label;
 };