From 4f204dcbc15056cdd047b06ac6111becda5c2915 Mon Sep 17 00:00:00 2001
From: Pavel Borzenkov <pavel.borzenkov@gmail.com>
Date: Tue, 2 Apr 2019 15:16:29 +0300
Subject: [PATCH] chunks: close all opened MmapFiles on NewDirReader error path
 (#575)

Signed-off-by: Pavel Borzenkov <pavel.borzenkov@gmail.com>
---
 CHANGELOG.md     |  1 +
 chunks/chunks.go | 10 ++++++----
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 80f502304..787a180c4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,7 @@
  - [REMOVED] `FromData` is considered unused so was removed.
  - [FEATURE] Added option WALSegmentSize -1 to disable the WAL.
  - [BUGFIX] Fsync the meta file to persist it on disk to avoid data loss in case of a host crash.
+ - [BUGFIX] Fix fd and vm_area leak on error path in chunks.NewDirReader
 
 ## 0.6.1
   - [BUGFIX] Update `last` after appending a non-overlapping chunk in `chunks.MergeOverlappingChunks`. [#539](https://github.com/prometheus/tsdb/pull/539)
diff --git a/chunks/chunks.go b/chunks/chunks.go
index 9e7540707..2d93d7c33 100644
--- a/chunks/chunks.go
+++ b/chunks/chunks.go
@@ -408,13 +408,16 @@ func NewDirReader(dir string, pool chunkenc.Pool) (*Reader, error) {
 	}
 
 	var (
-		bs []ByteSlice
-		cs []io.Closer
+		bs   []ByteSlice
+		cs   []io.Closer
+		merr tsdb_errors.MultiError
 	)
 	for _, fn := range files {
 		f, err := fileutil.OpenMmapFile(fn)
 		if err != nil {
-			return nil, errors.Wrapf(err, "mmap files")
+			merr.Add(errors.Wrap(err, "mmap files"))
+			merr.Add(closeAll(cs))
+			return nil, merr
 		}
 		cs = append(cs, f)
 		bs = append(bs, realByteSlice(f.Bytes()))
@@ -422,7 +425,6 @@ func NewDirReader(dir string, pool chunkenc.Pool) (*Reader, error) {
 
 	reader, err := newReader(bs, cs, pool)
 	if err != nil {
-		var merr tsdb_errors.MultiError
 		merr.Add(err)
 		merr.Add(closeAll(cs))
 		return nil, merr