Hi On Tue, Sep 8, 2026 at 8:49 PM Kim, Dongwon <[email protected]> wrote: > > Hi Marc-André, > > > Subject: Re: [PATCH] ui/gtk: Handle empty notebook state in menu handlers > > > > Hi > > > > On Tue, Sep 8, 2026 at 12:18 AM <[email protected]> wrote: > > > > > > From: Dongwon Kim <[email protected]> > > > > > > When the GTK notebook has no active page (e.g. before pages are added > > > or if all pages are detached/removed), gtk_notebook_get_current_page() > > > returns -1. Previously, this value was passed unchecked to > > > gd_vc_find_by_page(), which could result in unexpected lookups or NULL > > > dereferences. > > > > > > Update gd_vc_find_current() to explicitly return NULL when page < 0. > > > Additionally, add NULL checks for the current VirtualConsole across > > > all relevant UI menu callbacks to avoid dereferencing an invalid or > > > NULL pointer when no console tab is currently focused. > > > > This looks reasonable, but can it happen? if so, how? Rather than handling a > > situation that should not happen, I would rather crash or abort if we broke > > an > > invariant. > > > > thanks > > The mention of "NULL dereferences" in the commit message was inaccurate. > It's not causing a crash, but rather logic bugs. This happens when all VC tabs > are detached (untabified). In that state: > > gtk_notebook_get_current_page() returns -1. > > For any detached tab, gtk_notebook_page_num() also returns -1. > > Consequently, gd_vc_find_by_page(s, -1) matches the very first detached > console in s->vcs. Menu actions triggered on the empty main window mistakenly > route to that detached window instead of being ignored. >
Please correct the commit message then thanks > Thanks! > > > > > > > > > Cc: Daniel P. Berrangé <[email protected]> > > > Cc: Marc-André Lureau <[email protected]> > > > Signed-off-by: Dongwon Kim <[email protected]> > > > --- > > > ui/gtk.c | 56 > > > ++++++++++++++++++++++++++++++++++++++++++++++++++------ > > > 1 file changed, 50 insertions(+), 6 deletions(-) > > > > > > diff --git a/ui/gtk.c b/ui/gtk.c > > > index 7078d89d67..0b5139ef31 100644 > > > --- a/ui/gtk.c > > > +++ b/ui/gtk.c > > > @@ -184,6 +184,11 @@ static VirtualConsole > > *gd_vc_find_current(GtkDisplayState *s) > > > gint page; > > > > > > page = gtk_notebook_get_current_page(GTK_NOTEBOOK(s->notebook)); > > > + > > > + if (page < 0) { > > > + return NULL; > > > + } > > > + > > > return gd_vc_find_by_page(s, page); } > > > > > > @@ -1462,7 +1467,10 @@ static void gd_menu_show_tabs(GtkMenuItem > > *item, void *opaque) > > > } else { > > > gtk_notebook_set_show_tabs(GTK_NOTEBOOK(s->notebook), FALSE); > > > } > > > - gd_update_windowsize(vc); > > > + > > > + if (vc) { > > > + gd_update_windowsize(vc); > > > + } > > > } > > > > > > static int gd_vc_notebook_pos(GtkDisplayState *s, VirtualConsole > > > *target) @@ -1535,6 +1543,10 @@ static void > > gd_menu_untabify(GtkMenuItem *item, void *opaque) > > > GtkDisplayState *s = opaque; > > > VirtualConsole *vc = gd_vc_find_current(s); > > > > > > + if (!vc) { > > > + return; > > > + } > > > + > > > if (vc->type == GD_VC_GFX && > > > qemu_console_is_graphic(vc->gfx.dcl.con)) { > > > > > > gtk_check_menu_item_set_active(GTK_CHECK_MENU_ITEM(s->grab_item), > > > @@ -1588,7 +1600,10 @@ static void > > gd_menu_show_menubar(GtkMenuItem *item, void *opaque) > > > } else { > > > gtk_widget_hide(s->menu_bar); > > > } > > > - gd_update_windowsize(vc); > > > + > > > + if (vc) { > > > + gd_update_windowsize(vc); > > > + } > > > } > > > > > > static void gd_accel_show_menubar(void *opaque) @@ -1605,7 +1620,7 > > @@ > > > static void gd_menu_full_screen(GtkMenuItem *item, void *opaque) > > > if (!s->full_screen) { > > > gtk_notebook_set_show_tabs(GTK_NOTEBOOK(s->notebook), FALSE); > > > gtk_widget_hide(s->menu_bar); > > > - if (vc->type == GD_VC_GFX) { > > > + if (vc && vc->type == GD_VC_GFX) { > > > gtk_widget_set_size_request(vc->gfx.drawing_area, -1, -1); > > > } > > > gtk_window_fullscreen(GTK_WINDOW(s->window)); > > > @@ -1618,14 +1633,16 @@ static void gd_menu_full_screen(GtkMenuItem > > *item, void *opaque) > > > gtk_widget_show(s->menu_bar); > > > } > > > s->full_screen = FALSE; > > > - if (vc->type == GD_VC_GFX) { > > > + if (vc && vc->type == GD_VC_GFX) { > > > vc->gfx.scale_x = vc->gfx.preferred_scale; > > > vc->gfx.scale_y = vc->gfx.preferred_scale; > > > gd_update_windowsize(vc); > > > } > > > } > > > > > > - gd_update_cursor(vc); > > > + if (vc) { > > > + gd_update_cursor(vc); > > > + } > > > } > > > > > > static void gd_accel_full_screen(void *opaque) @@ -1639,6 +1656,10 @@ > > > static void gd_menu_zoom_in(GtkMenuItem *item, void *opaque) > > > GtkDisplayState *s = opaque; > > > VirtualConsole *vc = gd_vc_find_current(s); > > > > > > + if (!vc) { > > > + return; > > > + } > > > + > > > gtk_check_menu_item_set_active(GTK_CHECK_MENU_ITEM(s- > > >zoom_fit_item), > > > FALSE); > > > > > > @@ -1659,6 +1680,10 @@ static void gd_menu_zoom_out(GtkMenuItem > > *item, void *opaque) > > > GtkDisplayState *s = opaque; > > > VirtualConsole *vc = gd_vc_find_current(s); > > > > > > + if (!vc) { > > > + return; > > > + } > > > + > > > gtk_check_menu_item_set_active(GTK_CHECK_MENU_ITEM(s- > > >zoom_fit_item), > > > FALSE); > > > > > > @@ -1676,6 +1701,10 @@ static void gd_menu_zoom_fixed(GtkMenuItem > > *item, void *opaque) > > > GtkDisplayState *s = opaque; > > > VirtualConsole *vc = gd_vc_find_current(s); > > > > > > + if (!vc) { > > > + return; > > > + } > > > + > > > vc->gfx.scale_x = vc->gfx.preferred_scale; > > > vc->gfx.scale_y = vc->gfx.preferred_scale; > > > > > > @@ -1687,6 +1716,10 @@ static void gd_menu_zoom_fit(GtkMenuItem > > *item, void *opaque) > > > GtkDisplayState *s = opaque; > > > VirtualConsole *vc = gd_vc_find_current(s); > > > > > > + if (!vc) { > > > + return; > > > + } > > > + > > > if (gtk_check_menu_item_get_active(GTK_CHECK_MENU_ITEM(s- > > >zoom_fit_item))) { > > > s->free_scale = TRUE; > > > } else { > > > @@ -1800,6 +1833,11 @@ static void gd_menu_grab_input(GtkMenuItem > > *item, void *opaque) > > > VirtualConsole *vc = gd_vc_find_current(s); > > > > > > if (gd_is_grab_active(s)) { > > > + if (!vc) { > > > + gtk_check_menu_item_set_active(GTK_CHECK_MENU_ITEM(s- > > >grab_item), > > > + FALSE); > > > + return; > > > + } > > > gd_grab_keyboard(vc, "user-request-main-window"); > > > gd_grab_pointer(vc, "user-request-main-window"); > > > } else { > > > @@ -1807,7 +1845,9 @@ static void gd_menu_grab_input(GtkMenuItem > > *item, void *opaque) > > > gd_ungrab_pointer(s); > > > } > > > > > > - gd_update_cursor(vc); > > > + if (vc) { > > > + gd_update_cursor(vc); > > > + } > > > } > > > > > > static void gd_change_page(GtkNotebook *nb, gpointer arg1, guint > > > arg2, @@ -1983,6 +2023,10 @@ static void gd_menu_copy(GtkMenuItem > > *item, void *opaque) > > > GtkDisplayState *s = opaque; > > > VirtualConsole *vc = gd_vc_find_current(s); > > > > > > + if (!vc) { > > > + return; > > > + } > > > + > > > #if VTE_CHECK_VERSION(0, 50, 0) > > > vte_terminal_copy_clipboard_format(VTE_TERMINAL(vc->vte.terminal), > > > VTE_FORMAT_TEXT); > > > -- > > > 2.43.0 > > > > > > > > > > > > -- > > Marc-André Lureau -- Marc-André Lureau
