png_set_PLTE(png_structp png_ptr, png_infop info_ptr,
    png_colorp palette, int num_palette)
 {
 
    png_debug1(1, "in %s storage function", "PLTE");
 
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
   if (num_palette < 0 || num_palette > PNG_MAX_PALETTE_LENGTH)
    {
       if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
          png_error(png_ptr, "Invalid palette length");
      else
      {
         png_warning(png_ptr, "Invalid palette length");
         return;
      }
   }

   /* It may not actually be necessary to set png_ptr->palette here;
    * we do it for backward compatibility with the way the png_handle_tRNS
    * function used to do the allocation.
    */
#ifdef PNG_FREE_ME_SUPPORTED
   png_free_data(png_ptr, info_ptr, PNG_FREE_PLTE, 0);
 #endif
 
    /* Changed in libpng-1.2.1 to allocate PNG_MAX_PALETTE_LENGTH instead
    * of num_palette entries, in case of an invalid PNG file that has
    * too-large sample values.
     */
    png_ptr->palette = (png_colorp)png_calloc(png_ptr,
       PNG_MAX_PALETTE_LENGTH * png_sizeof(png_color));
   png_memcpy(png_ptr->palette, palette, num_palette * png_sizeof(png_color));
   info_ptr->palette = png_ptr->palette;
   info_ptr->num_palette = png_ptr->num_palette = (png_uint_16)num_palette;

#ifdef PNG_FREE_ME_SUPPORTED
   info_ptr->free_me |= PNG_FREE_PLTE;
#else
   png_ptr->flags |= PNG_FLAG_FREE_PLTE;
#endif

   info_ptr->valid |= PNG_INFO_PLTE;
}

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.