If postcopy has finished, it frees the array.
But vhost-user unregister it at cleanup time.

Signed-off-by: Juan Quintela <quintela@redhat.com>
---
 migration/postcopy-ram.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c
index e721f69d0f..d18b5d05b2 100644
--- a/migration/postcopy-ram.c
+++ b/migration/postcopy-ram.c
@@ -1457,6 +1457,10 @@ void postcopy_unregister_shared_ufd(struct PostCopyFD *pcfd)
     MigrationIncomingState *mis = migration_incoming_get_current();
     GArray *pcrfds = mis->postcopy_remote_fds;
 
+    if (!pcrfds) {
+        /* migration has already finished and freed the array */
+        return;
+    }
     for (i = 0; i < pcrfds->len; i++) {
         struct PostCopyFD *cur = &g_array_index(pcrfds, struct PostCopyFD, i);
         if (cur->fd == pcfd->fd) {
-- 
2.33.1