From: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
This place is not obvious, nbd_export_close may theoretically reduce
refcount to 0. It may happen if someone calls nbd_export_put on named
export not through nbd_export_set_name when refcount is 1.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
Reviewed-by: Eric Blake <ebl...@redhat.com>
Reviewed-by: Max Reitz <mre...@redhat.com>
Message-Id: <20171207155102.66622-2-vsement...@virtuozzo.com>
Signed-off-by: Eric Blake <ebl...@redhat.com>
---
nbd/server.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/nbd/server.c b/nbd/server.c
index e443b3cf5c..6cf2eeb2c1 100644
--- a/nbd/server.c
+++ b/nbd/server.c
@@ -1190,6 +1190,12 @@ void nbd_export_put(NBDExport *exp)
nbd_export_close(exp);
}
+ /* nbd_export_close() may theoretically reduce refcount to 0. It may happen
+ * if someone calls nbd_export_put() on named export not through
+ * nbd_export_set_name() when refcount is 1. So, let's assert that
+ * it is > 0.
+ */
+ assert(exp->refcount > 0);
if (--exp->refcount == 0) {
assert(exp->name == NULL);
assert(exp->description == NULL);
--
2.14.3
