rbd-mirror: do not attempt to unlink from more recent snapshots

The snapshot-based mirroring replayer should only attempt to unlink
from any snapshots that are older than the end remote snapshot id to
prevent the remote side from incorrectly deleted the snapshot.

Fixes: https://tracker.ceph.com/issues/48527
Signed-off-by: Jason Dillaman <dillaman@redhat.com>
(cherry picked from commit 78f8abce2d90d7c9bcf7b4bd4d805c3fe0b39b03)

diff --git a/src/test/rbd_mirror/image_replayer/snapshot/test_mock_Replayer.cc b/src/test/rbd_mirror/image_replayer/snapshot/test_mock_Replayer.cc
index d1117bb79eb6f8b2f1731b3044f15018788c67f9..4ce139d21f4e0da70052b4432a6c5cc8ff496141 100644 (file)
--- a/src/test/rbd_mirror/image_replayer/snapshot/test_mock_Replayer.cc
+++ b/src/test/rbd_mirror/image_replayer/snapshot/test_mock_Replayer.cc
@@ -783,7 +783,24 @@ TEST_F(TestMockImageReplayerSnapshotReplayer, SyncSnapshot) {
          1, true, 0, {{1, CEPH_NOSNAP}}},
        0, {}, 0, 0, {}}},
     }, 0);
-  expect_is_refresh_required(mock_remote_image_ctx, false);
+  expect_is_refresh_required(mock_remote_image_ctx, true);
+  expect_refresh(
+    mock_remote_image_ctx, {
+      {2U, librbd::SnapInfo{"snap2", cls::rbd::UserSnapshotNamespace{},
+       0, {}, 0, 0, {}}},
+      {3U, librbd::SnapInfo{"snap3", cls::rbd::MirrorSnapshotNamespace{
+         cls::rbd::MIRROR_SNAPSHOT_STATE_PRIMARY, {""},
+         "", CEPH_NOSNAP, true, 0, {}},
+       0, {}, 0, 0, {}}},
+      {4U, librbd::SnapInfo{"snap4", cls::rbd::MirrorSnapshotNamespace{
+         cls::rbd::MIRROR_SNAPSHOT_STATE_PRIMARY, {"remote mirror peer uuid"},
+         "", CEPH_NOSNAP, true, 0, {}},
+       0, {}, 0, 0, {}}},
+      {5U, librbd::SnapInfo{"snap5", cls::rbd::MirrorSnapshotNamespace{
+         cls::rbd::MIRROR_SNAPSHOT_STATE_PRIMARY, {"remote mirror peer uuid"},
+         "", CEPH_NOSNAP, true, 0, {}},
+       0, {}, 0, 0, {}}}
+    }, 0);
   expect_snapshot_copy(mock_snapshot_copy_request, 1, 4, 11,
                        {{1, 11}, {2, 12}, {4, CEPH_NOSNAP}}, 0);
   expect_get_image_state(mock_get_image_state_request, 4, 0);

diff --git a/src/tools/rbd_mirror/image_replayer/snapshot/Replayer.cc b/src/tools/rbd_mirror/image_replayer/snapshot/Replayer.cc
index 6fa7277ef474b9cf749e1a65fe7ae71bf226b68e..f46270c927fa554515c988efa4d5750f6bf43be7 100644 (file)
--- a/src/tools/rbd_mirror/image_replayer/snapshot/Replayer.cc
+++ b/src/tools/rbd_mirror/image_replayer/snapshot/Replayer.cc
@@ -555,7 +555,10 @@ void Replayer<I>::scan_remote_mirror_snapshots(
         ceph_assert(m_local_mirror_snap_ns.primary_mirror_uuid ==
                       m_state_builder->remote_mirror_uuid);
 
-        unlink_snap_ids.insert(remote_snap_id);
+        if (m_remote_snap_id_end == CEPH_NOSNAP) {
+          // haven't found the end snap so treat this as a candidate for unlink
+          unlink_snap_ids.insert(remote_snap_id);
+        }
         if (m_local_mirror_snap_ns.complete &&
             m_local_mirror_snap_ns.primary_snap_id >= remote_snap_id) {
           // skip past completed remote snapshot