xlib/shm: Discard damage upon shm finish

Both to make sure we do not leak the memory, but to also prevent
_cairo_xlib_surface_put_shm() from operating upon the finished shm
surface after the display is closed.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=58253
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

3 files changed, 13 insertions, 0 deletions

diff --git a/src/cairo-damage-private.h b/src/cairo-damage-private.h
index 28768fd30..97b177e86 100644
--- a/src/cairo-damage-private.h
+++ b/src/cairo-damage-private.h
@@ -60,6 +60,9 @@ cairo_private cairo_damage_t *
 _cairo_damage_create (void);
 
 cairo_private cairo_damage_t *
+_cairo_damage_create_in_error (cairo_status_t status);
+
+cairo_private cairo_damage_t *
 _cairo_damage_add_box (cairo_damage_t *damage,
 		       const cairo_box_t *box);
 
diff --git a/src/cairo-damage.c b/src/cairo-damage.c
index 1e06b2649..63191fee9 100644
--- a/src/cairo-damage.c
+++ b/src/cairo-damage.c
@@ -40,6 +40,13 @@
 static const cairo_damage_t __cairo_damage__nil = { CAIRO_STATUS_NO_MEMORY };
 
 cairo_damage_t *
+_cairo_damage_create_in_error (cairo_status_t status)
+{
+    _cairo_error_throw (status);
+    return (cairo_damage_t *) &__cairo_damage__nil;
+}
+
+cairo_damage_t *
 _cairo_damage_create (void)
 {
     cairo_damage_t *damage;
diff --git a/src/cairo-xlib-surface-shm.c b/src/cairo-xlib-surface-shm.c
index 2c2858cd2..ff0aaf876 100644
--- a/src/cairo-xlib-surface-shm.c
+++ b/src/cairo-xlib-surface-shm.c
@@ -710,6 +710,9 @@ _cairo_xlib_shm_surface_finish (void *abstract_surface)
     cairo_xlib_display_t *display;
     cairo_status_t status;
 
+    _cairo_damage_destroy (shm->image.base.damage);
+    shm->image.base.damage = _cairo_damage_create_in_error (CAIRO_STATUS_SURFACE_FINISHED);
+
     status = _cairo_xlib_display_acquire (shm->image.base.device, &display);
     if (unlikely (status))
 	return status;