[FIXED] SkipMsg left in mb.dmap after recovery

server/filestore.go

@@ -1458,15 +1458,14 @@ func (mb *msgBlock) rebuildStateLocked() (*LostStreamData, []uint64, error) {
 		if seq == 0 || seq&ebit != 0 || seq < fseq {
 			seq = seq &^ ebit
 			if seq >= fseq {
-				// Only add to dmap if past recorded first seq and non-zero.
-				if seq != 0 {
-					addToDmap(seq)
-				}
 				atomic.StoreUint64(&mb.last.seq, seq)
 				mb.last.ts = ts
 				if mb.msgs == 0 {
 					atomic.StoreUint64(&mb.first.seq, seq+1)
 					mb.first.ts = 0
+				} else if seq != 0 {
+					// Only add to dmap if past recorded first seq and non-zero.
+					addToDmap(seq)
 				}
 			}
 			index += rl
@@ -7425,11 +7424,7 @@ func (fs *fileStore) State() StreamState {
 			}
 			// Add in deleted.
 			mb.dmap.Range(func(seq uint64) bool {
-				if seq < fseq {
-					mb.dmap.Delete(seq)
-				} else {
-					state.Deleted = append(state.Deleted, seq)
-				}
+				state.Deleted = append(state.Deleted, seq)
 				return true
 			})
 			mb.mu.Unlock()

server/filestore_test.go

@@ -8887,3 +8887,58 @@ func changeDirectoryPermission(directory string, mode fs.FileMode) error {
 	})
 	return err
 }
+
+func TestFileStoreLeftoverSkipMsgInDmap(t *testing.T) {
+	storeDir := t.TempDir()
+	fs, err := newFileStore(
+		FileStoreConfig{StoreDir: storeDir},
+		StreamConfig{Name: "zzz", Subjects: []string{"test.*"}, Storage: FileStorage, MaxMsgsPer: 1},
+	)
+	require_NoError(t, err)
+	defer fs.Stop()
+
+	getLmbState := func(fs *fileStore) (uint64, uint64, int) {
+		fs.mu.RLock()
+		lmb := fs.lmb
+		fs.mu.RUnlock()
+		lmb.mu.RLock()
+		fseq := atomic.LoadUint64(&lmb.first.seq)
+		lseq := atomic.LoadUint64(&lmb.last.seq)
+		dmaps := lmb.dmap.Size()
+		lmb.mu.RUnlock()
+		return fseq, lseq, dmaps
+	}
+
+	// Only skip a message.
+	fs.SkipMsg()
+
+	// Confirm state.
+	state := fs.State()
+	require_Equal(t, state.FirstSeq, 2)
+	require_Equal(t, state.LastSeq, 1)
+	require_Equal(t, state.NumDeleted, 0)
+	fseq, lseq, dmaps := getLmbState(fs)
+	require_Equal(t, fseq, 2)
+	require_Equal(t, lseq, 1)
+	require_Len(t, dmaps, 0)
+
+	// Stop without writing index.db so we recover based on just the blk file.
+	require_NoError(t, fs.stop(false, false))
+
+	fs, err = newFileStore(
+		FileStoreConfig{StoreDir: storeDir},
+		StreamConfig{Name: "zzz", Subjects: []string{"test.*"}, Storage: FileStorage, MaxMsgsPer: 1},
+	)
+	require_NoError(t, err)
+	defer fs.Stop()
+
+	// Confirm the skipped message is not included in the deletes.
+	state = fs.State()
+	require_Equal(t, state.FirstSeq, 2)
+	require_Equal(t, state.LastSeq, 1)
+	require_Equal(t, state.NumDeleted, 0)
+	fseq, lseq, dmaps = getLmbState(fs)
+	require_Equal(t, fseq, 2)
+	require_Equal(t, lseq, 1)
+	require_Len(t, dmaps, 0)
+}