From c8eb017867c9dc5068826129b16133b7e99886f0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Fabian=20Gr=C3=BCnbichler?= <f.gruenbichler@proxmox.com>
Date: Tue, 22 Sep 2020 08:56:12 +0200
Subject: [PATCH] zfs: handle unexpectedly missing snapshots better
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Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
---
 PVE/Storage/ZFSPoolPlugin.pm | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/PVE/Storage/ZFSPoolPlugin.pm b/PVE/Storage/ZFSPoolPlugin.pm
index 10354b3..6fa9127 100644
--- a/PVE/Storage/ZFSPoolPlugin.pm
+++ b/PVE/Storage/ZFSPoolPlugin.pm
@@ -472,6 +472,10 @@ sub volume_rollback_is_possible {
     my ($class, $scfg, $storeid, $volname, $snap) = @_;
 
     my $recentsnap = $class->zfs_get_latest_snapshot($scfg, $volname);
+
+    die "can't rollback, no snapshots exist at all\n"
+	if !defined($recentsnap);
+
     if ($snap ne $recentsnap) {
 	die "can't rollback, more recent snapshots exist\n";
     }