diff options
author | Olivier Fourdan <ofourdan@redhat.com> | 2017-08-31 10:23:00 +0200 |
---|---|---|
committer | Peter Hutterer <peter.hutterer@who-t.net> | 2017-09-05 11:35:40 +1000 |
commit | cdd0352ba05d4d8482aaca41797e05d40e58da36 (patch) | |
tree | f4b3fdf5eea5c7f6148813853ffeef698ad703df | |
parent | 3fbc3c3eefd3803d0c4e86e42595d8a891aeb5f2 (diff) |
xwayland: Fix a segfault with pointer locking
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 <ofourdan@redhat.com>
Acked-by: Peter Hutterer <peter.hutterer@who-t.net>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
-rw-r--r-- | hw/xwayland/xwayland-input.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/hw/xwayland/xwayland-input.c b/hw/xwayland/xwayland-input.c index 0ef073f64..d45bee410 100644 --- a/hw/xwayland/xwayland-input.c +++ b/hw/xwayland/xwayland-input.c @@ -2762,6 +2762,9 @@ 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); |