Keep thumbnail path bounds and check UUID status in stress test

src/video/video.c

@@ -788,7 +788,9 @@ static int vc_first_frame(AVFormatContext* format, AVCodecContext* decoder, int
 }
 
 int video_extract_thumbnail(const char* src, const char* dst, int max_w) {
-    if (file_io_paths(src, dst)) return -1;
+    if (!src || !dst || strlen(src) >= VIDEO_PATH_MAX || strlen(dst) >= VIDEO_PATH_MAX || file_io_paths(src, dst)) {
+        DEBUG_ERROR(DEBUG_CATEGORY_VIDEO, "video thumbnail invalid/identical/oversized paths"); return -1;
+    }
     if (max_w <= 0) max_w = 320;
     if (max_w < 2) { DEBUG_ERROR(DEBUG_CATEGORY_VIDEO, "video thumbnail width must be >=2"); return -1; }
     video_ffmpeg_init();

tests/test_media_async.c

@@ -113,7 +113,7 @@ static void* worker_thread(void* arg) {
             real_op = 3;
             uint8_t uuid[16];
             t0 = now_us();
-            ma_uuid(uuid);
+            if (ma_uuid(uuid)) st->errors++;
             elapsed = now_us() - t0;
             int zero = 1;
             for (int i = 0; i < 16; i++) { if (uuid[i] != 0) { zero = 0; break; } }