xen/pvcalls: Fix a check in pvcalls_front_remove()
bedata->ref can't be less than zero because it's unsigned. This affects
certain error paths in probe. We first set ->ref = -1 and then we set
it to a valid value later.
Fixes: 219681909913 ("xen/pvcalls: connect to the backend")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
diff --git a/drivers/xen/pvcalls-front.c b/drivers/xen/pvcalls-front.c
index afa3f1b..d1e1d8d 100644
--- a/drivers/xen/pvcalls-front.c
+++ b/drivers/xen/pvcalls-front.c
@@ -1103,7 +1103,7 @@ static int pvcalls_front_remove(struct xenbus_device *dev)
kfree(map);
}
}
- if (bedata->ref >= 0)
+ if (bedata->ref != -1)
gnttab_end_foreign_access(bedata->ref, 0, 0);
kfree(bedata->ring.sring);
kfree(bedata);