Xwayland would crash in some circumstances while trying to issue a pointer locking when the cursor is hidden when there is no seat focus window set.
The crash signature looks like: #0 zwp_pointer_constraints_v1_lock_pointer () #1 xwl_pointer_warp_emulator_lock () at xwayland-input.c:2584 #2 xwl_seat_maybe_lock_on_hidden_cursor () at xwayland-input.c:2756 #3 xwl_seat_maybe_lock_on_hidden_cursor () at xwayland-input.c:2765 #4 xwl_seat_cursor_visibility_changed () at xwayland-input.c:2768 #5 xwl_set_cursor () at xwayland-cursor.c:245 #6 miPointerUpdateSprite () at mipointer.c:468 #7 miPointerDisplayCursor () at mipointer.c:206 #8 CursorDisplayCursor () at cursor.c:150 #9 AnimCurDisplayCursor () at animcur.c:220 #10 ChangeToCursor () at events.c:936 #11 ActivatePointerGrab () at events.c:1542 #12 GrabDevice () at events.c:5120 #13 ProcGrabPointer () at events.c:4908 #14 Dispatch () at dispatch.c:478 #15 dix_main () at main.c:276 xwl_pointer_warp_emulator_lock() tries to use the surface from the xwl_seat->focus_window leading to a NULL pointer dereference when that value is NULL. Check that xwl_seat->focus_window is not NULL earlier in the stack in xwl_seat_maybe_lock_on_hidden_cursor() and return early if not the case to avoid the crash. Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=102474 Signed-off-by: Olivier Fourdan <ofour...@redhat.com> --- hw/xwayland/xwayland-input.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/hw/xwayland/xwayland-input.c b/hw/xwayland/xwayland-input.c index 92e530d0d..acb467b91 100644 --- a/hw/xwayland/xwayland-input.c +++ b/hw/xwayland/xwayland-input.c @@ -2749,6 +2749,9 @@ xwl_seat_maybe_lock_on_hidden_cursor(struct xwl_seat *xwl_seat) !xwl_seat->cursor_confinement_window) return FALSE; + if (!xwl_seat->focus_window) + return FALSE; + if (xwl_seat->confined_pointer) xwl_seat_destroy_confined_pointer(xwl_seat); -- 2.13.5 _______________________________________________ wayland-devel mailing list wayland-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/wayland-devel
