Several potential bugs of NULL Pointer Dereference

[yuxuan He]

Ubuntu version: 18.04
ncurses version:6.1

Hello,I found some potential bugs in package ncurses-6.1 .Would you help me check whether the bugs mentioned below are true? Thank you very much for your patience.

============================================================================================================

step 1 :
  In file ncurses-6.1/ncurses/tinfo/lib_data.c , function _nc_screen_of line 287 :
    Select the false branch at this point (win!=null is false)

step 2 :
  In file ncurses-6.1/ncurses/tinfo/lib_data.c , function _nc_screen_of line 290 :
    null assigned to sp reaches here

step 3 :
  In file ncurses-6.1/ncurses/tinfo/lib_data.c , function _nc_screen_of line 290 :
    Return sp to caller, which can be null

step 4 :
  In file ncurses-6.1/ncurses/base/resizeterm.c , function adjust_window line 218 :
    Function _nc_screen_of executes and returns

step 5 :
  In file ncurses-6.1/ncurses/base/resizeterm.c , function adjust_window line 218 :
    Load value from _nc_screen_of(win)->_topstolen

============================================================================================================

step 1 :
  In file ncurses-6.1/ncurses/base/nc_panel.c , function _nc_panelhook line 42 :
    Select the false branch at this point (SP!=null is false)

step 2 :
  In file ncurses-6.1/ncurses/base/nc_panel.c , function _nc_panelhook line 40 :
    Return null to caller

step 3 :
  In file ncurses-6.1/panel/p_new.c , function root_panel line 56 :
    Function _nc_panelhook executes and stores the return value to ph (ph can be null)

step 4 :
  In file ncurses-6.1/panel/p_new.c , function root_panel line 62 :
    Load value from ph->stdscr_pseudo_panel （_nc_stdscr_pseudo_panel is defined in panel.priv.h）

============================================================================================================

step 1 :
  In file ncurses-6.1/ncurses/base/nc_panel.c , function _nc_panelhook line 42 :
    Select the false branch at this point (SP!=null is false)

step 2 :
  In file ncurses-6.1/ncurses/base/nc_panel.c , function _nc_panelhook line 40 :
    Return null to caller

step 3 :
  In file ncurses-6.1/panel/p_move.c , function move_panel line 51 :
    Function _nc_panelhook_sp executes and stores the return value to ph (ph can be null)
  in file panel.priv.h(#define GetHook(pan) SCREEN* sp = _nc_screen_of(pan->win); )

step 4 :
  In file ncurses-6.1/panel/p_move.c , function move_panel line 52 :
    Load value from ph->bottom_panel
  in file panel.priv.h(#define IS_LINKED(p) (((p)->above || (p)->below ||((p)==_nc_bottom_panel)) ? TRUE : FALSE))

============================================================================================================

step 1 :
  In file ncurses-6.1/ncurses/tinfo/lib_data.c , function _nc_screen_of line 287 :
    Select the false branch at this point (win!=null is false)

step 2 :
  In file ncurses-6.1/ncurses/tinfo/lib_data.c , function _nc_screen_of line 290 :
    null assigned to sp reaches here

step 3 :
  In file ncurses-6.1/ncurses/tinfo/lib_data.c , function _nc_screen_of line 290 :
    Return sp to caller, which can be null

step 4 :
  In file ncurses-6.1/menu/m_sub.c , function set_menu_sub line 68 :
    Function _nc_screen_of executes and stores the return value to sp (sp can be null)

step 5 :
  In file ncurses-6.1/menu/m_sub.c , function set_menu_sub line 70 :
    Load value from sp->_stdscr

============================================================================================================

step 1 :
  In file ncurses-6.1/ncurses/base/nc_panel.c , function _nc_panelhook_sp line 42 :
    Select the false branch at this point (SP!=null is false)

step 2 :
  In file ncurses-6.1/ncurses/base/nc_panel.c , function _nc_panelhook_sp line 40 :
    Return null to caller

step 3 :
  In file ncurses-6.1/panel/p_hide.c , function hide_panel line 50 :
    Function _nc_panelhook_sp executes and stores the return value to ph (ph can be null)
  in file panel.priv.h(#define GetHook(pan) SCREEN* sp = _nc_screen_of(pan->win); )

step 4 :
  In file ncurses-6.1/panel/p_hide.c , function hide_panel line 55 :
    Load value from ph->bottom_panel and assign to pan
  HIDE_PANEL is defined in file panel.priv.h

============================================================================================================

step 1 :
  In file ncurses-6.1/ncurses/base/nc_panel.c , function _nc_panelhook_sp line 42 :
    Select the false branch at this point (SP!=null is false)

step 2 :
  In file ncurses-6.1/ncurses/base/nc_panel.c , function _nc_panelhook_sp line 40 :
    Return null to caller

step 3 :
  In file ncurses-6.1/panel/p_new.c , function new_panel line 96 :
    Function _nc_panelhook_sp executes and stores the return value to ph (ph can be null)
  GetWindowHook is defined in panel.priv.h

step 4 :
  In file ncurses-6.1/panel/p_new.c , function new_panel line 103 :
    Load value from ph->stdscr_pseudo_panel

============================================================================================================

step 1 :
  In file ncurses-6.1/ncurses/base/nc_panel.c , function _nc_panelhook_sp line 42 :
    Select the false branch at this point (SP!=null is false)

step 2 :
  In file ncurses-6.1/ncurses/base/nc_panel.c , function _nc_panelhook_sp line 40 :
    Return null to caller

step 3 :
  In file ncurses-6.1/panel/p_move.c , function move_panel line 51 :
    Function _nc_panelhook_sp executes and stores the return value to ph (ph can be null)
  GetHook is defined panel.priv.h

step 4 :
  In file ncurses-6.1/panel/p_move.c , function move_panel line 55 :
    Load value from ph->bottom_panel and assign to pan

============================================================================================================

step 1 :
  In file ncurses-6.1/ncurses/base/nc_panel.c , function _nc_panelhook_sp line 42 :
    Select the false branch at this point (SP!=null is false)

step 2 :
  In file ncurses-6.1/ncurses/base/nc_panel.c , function _nc_panelhook_sp line 40 :
    Return null to caller

step 3 :
  In file ncurses-6.1/panel/p_delete.c , function del_panel line 52 :
    Function _nc_panelhook_sp executes and stores the return value to ph (ph can be null)
  GetHook is defined panel.priv.h

step 4 :
  In file ncurses-6.1/panel/p_delete.c , function del_panel line 53 :
    Load value from ph->bottom_panel

============================================================================================================

step 1 :
  In file ncurses-6.1/ncurses/tinfo/lib_data.c , function _nc_screen_of line 287 :
    Select the false branch at this point (win!=null is false)

step 2 :
  In file ncurses-6.1/ncurses/tinfo/lib_data.c , function _nc_screen_of line 290 :
    null assigned to sp reaches here

step 3 :
  In file ncurses-6.1/ncurses/tinfo/lib_data.c , function _nc_screen_of line 290 :
    Return sp to caller, which can be null

step 4 :
  In file ncurses-6.1/menu/m_win.c , function set_menu_win line 68 :
    Function _nc_screen_of executes and stores the return value to sp (sp can be null)

step 5 :
  In file ncurses-6.1/menu/m_win.c , function set_menu_win line 70 :
    Load value from sp->_stdscr

============================================================================================================

step 1 :
  In file ncurses-6.1/ncurses/base/nc_panel.c , function _nc_panelhook_sp line 42 :
    Select the false branch at this point (SP!=null is false)

step 2 :
  In file ncurses-6.1/ncurses/base/nc_panel.c , function _nc_panelhook_sp line 40 :
    Return null to caller

step 3 :
  In file ncurses-6.1/panel/p_show.c , function show_panel line 50 :
    Function _nc_panelhook_sp executes and stores the return value to ph (ph can be null)
  GetHook is defined panel.priv.h

step 4 :
  In file ncurses-6.1/panel/p_show.c , function show_panel line 52 :
    Load value from ph->bottom_panel
  Is_Top is defined panel.priv.h

============================================================================================================

step 1 :
  In file ncurses-6.1/ncurses/base/nc_panel.c , function _nc_panelhook_sp line 42 :
    Select the false branch at this point (SP!=null is false)

step 2 :
  In file ncurses-6.1/ncurses/base/nc_panel.c , function _nc_panelhook_sp line 40 :
    Return null to caller

step 3 :
  In file ncurses-6.1/panel/p_hide.c , function hide_panel line 50 :
    Function _nc_panelhook_sp executes and stores the return value to ph (ph can be null)
  GetHook is defined panel.priv.h

step 4 :
  In file ncurses-6.1/panel/p_hide.c , function hide_panel line 55 :
    Load value from ph->bottom_panel
  dBug is defined panel.priv.h

============================================================================================================

step 1 :
  In file ncurses-6.1/ncurses/base/nc_panel.c , function _nc_panelhook_sp line 42 :
    Select the false branch at this point (SP!=null is false)

step 2 :
  In file ncurses-6.1/ncurses/base/nc_panel.c , function _nc_panelhook_sp line 40 :
    Return null to caller

step 3 :
  In file ncurses-6.1/panel/p_show.c , function show_panel line 50 :
    Function _nc_panelhook_sp executes and stores the return value to ph (ph can be null)
  GetHook is defined panel.priv.h

step 4 :
  In file ncurses-6.1/panel/p_show.c , function show_panel line 52 :
    Load value from ph->top_panel
  Is_Top is defined in panel.priv.h

============================================================================================================

step 1 :
  In file ncurses-6.1/ncurses/base/nc_panel.c , function _nc_panelhook_sp line 42 :
    Select the false branch at this point (SP!=null is false)

step 2 :
  In file ncurses-6.1/ncurses/base/nc_panel.c , function _nc_panelhook_sp line 40 :
    Return null to caller

step 3 :
  In file ncurses-6.1/panel/p_delete.c , function del_panel line 52 :
    Function _nc_panelhook_sp executes and stores the return value to ph (ph can be null)
  GetHook is defined panel.priv.h

step 4 :
  In file ncurses-6.1/panel/p_delete.c , function del_panel line 53 :
    Load value from ph->bottom_panel and assign to pan
  HIDE_PANEL is defined in panel.priv.h

[Thomas Dickey (dickey-his)]

There's no test-program which demonstrates the problem,
so there is no possibility to analyze these comments.

By the way, Ubuntu provides by itself no solutions or improvements of any type for ncurses.