Without this, xwl_present_reset_timer would call
xwl_present_timer_callback if the timer was originally armed over a
second ago. xwl_present_timer_callback would call xwl_present_msc_bump,
which could end up hooking up the window to
xwl_window->frame_callback_list again. This would lead to use-after-free
in xwl_present_cleanup:
Invalid write of size 8
at 0x42B65C: __xorg_list_del (list.h:183)
by 0x42B693: xorg_list_del (list.h:204)
by 0x42C041: xwl_present_cleanup (xwayland-present.c:354)
by 0x423669: xwl_destroy_window (xwayland-window.c:770)
by 0x4FDDC5: compDestroyWindow (compwindow.c:620)
by 0x5233FB: damageDestroyWindow (damage.c:1590)
by 0x501C5F: DbeDestroyWindow (dbe.c:1326)
by 0x4EF35B: FreeWindowResources (window.c:1018)
by 0x4EF687: DeleteWindow (window.c:1086)
by 0x4E24B3: doFreeResource (resource.c:885)
by 0x4E2ED7: FreeClientResources (resource.c:1151)
by 0x4ACBA4: CloseDownClient (dispatch.c:3546)
Address 0x12f44980 is 144 bytes inside a block of size 160 free'd
at 0x48470E4: free (vg_replace_malloc.c:872)
by 0x423115: xwl_unrealize_window (xwayland-window.c:621)
by 0x4FCDD8: compUnrealizeWindow (compwindow.c:292)
by 0x4F3F5C: UnrealizeTree (window.c:2805)
by 0x4F424B: UnmapWindow (window.c:2863)
by 0x4EF58C: DeleteWindow (window.c:1075)
by 0x4E24B3: doFreeResource (resource.c:885)
by 0x4E2ED7: FreeClientResources (resource.c:1151)
by 0x4ACBA4: CloseDownClient (dispatch.c:3546)
by 0x5E27EE: ClientReady (connection.c:599)
by 0x5E6CB7: ospoll_wait (ospoll.c:657)
by 0x5DE6CD: WaitForSomething (WaitFor.c:208)
Block was alloc'd at
at 0x4849464: calloc (vg_replace_malloc.c:1328)
by 0x4229CE: ensure_surface_for_window (xwayland-window.c:439)
by 0x4231E8: xwl_window_set_window_pixmap (xwayland-window.c:647)
by 0x5232D6: damageSetWindowPixmap (damage.c:1565)
by 0x4FC7BC: compSetPixmapVisitWindow (compwindow.c:129)
by 0x4EDB3F: TraverseTree (window.c:441)
by 0x4FC851: compSetPixmap (compwindow.c:151)
by 0x4F8C1A: compAllocPixmap (compalloc.c:616)
by 0x4FC938: compCheckRedirect (compwindow.c:174)
by 0x4FCD1D: compRealizeWindow (compwindow.c:274)
by 0x4F36EC: RealizeTree (window.c:2606)
by 0x4F39F5: MapWindow (window.c:2683)
Fixes: 288ec0e046 ("xwayland/present: Run fallback timer callback after more than a second")
Tested-by: Olivier Fourdan <ofourdan@redhat.com>
Reviewed-by: Olivier Fourdan <ofourdan@redhat.com>
102764b683