From 36367a99eb803a7941f6cbfd6086e7a71bf91e21 Mon Sep 17 00:00:00 2001
From: Andrew Price <anprice@redhat.com>
Date: Tue, 29 Oct 2019 11:27:06 +0000
Subject: [PATCH] fence_virtd: Fix segfault in vl_get when no domains are found

If virConnectListAllDomains() returns 0 on every iteration, the loop
will end with a vl == NULL and the pointer dereference in the qsort()
call will result in a segfault. Check for NULL on completion of the loop
to guard against that.

Signed-off-by: Andrew Price <anprice@redhat.com>
---
 server/virt.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/server/virt.c b/server/virt.c
index 9710791..ed08e0c 100644
--- a/server/virt.c
+++ b/server/virt.c
@@ -128,6 +128,9 @@ virt_list_t *vl_get(virConnectPtr *vp, int vp_count, int my_id)
 
 		_free_dom_list(dom_list, ret);
 	}
+	/* No domains found */
+	if (!vl)
+		return NULL;
 
 	/* We have all the locally running domains & states now */
 	/* Sort */