From 930ae3dbcb11091955ca936c280d13f24494b245 Mon Sep 17 00:00:00 2001
From: Aaron Lehmann <aaron.lehmann@docker.com>
Date: Wed, 30 Mar 2016 19:26:12 -0700
Subject: [PATCH] Pull: only close temporary file once

Close could be called twice on a temporary download file, which could
have bad side effects.

This fixes the problem by setting to ld.tmpFile to nil when the download
completes sucessfully. Then the call to ld.Close will have no effect,
and only the download manager will close the temporary file when it's
done extracting the layer from it. ld.Close will be responsible for
closing the file if we hit the retry limit and there is still a partial
download present.

Fixes #21675

Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
---
 distribution/pull_v1.go | 15 ++++++++++++++-
 distribution/pull_v2.go | 14 +++++++++++++-
 2 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/distribution/pull_v1.go b/distribution/pull_v1.go
index a8ae624915..86fad2ef7a 100644
--- a/distribution/pull_v1.go
+++ b/distribution/pull_v1.go
@@ -330,7 +330,20 @@ func (ld *v1LayerDescriptor) Download(ctx context.Context, progressOutput progre
 	logrus.Debugf("Downloaded %s to tempfile %s", ld.ID(), ld.tmpFile.Name())
 
 	ld.tmpFile.Seek(0, 0)
-	return ld.tmpFile, ld.layerSize, nil
+
+	// hand off the temporary file to the download manager, so it will only
+	// be closed once
+	tmpFile := ld.tmpFile
+	ld.tmpFile = nil
+
+	return ioutils.NewReadCloserWrapper(tmpFile, func() error {
+		tmpFile.Close()
+		err := os.RemoveAll(tmpFile.Name())
+		if err != nil {
+			logrus.Errorf("Failed to remove temp file: %s", tmpFile.Name())
+		}
+		return err
+	}), ld.layerSize, nil
 }
 
 func (ld *v1LayerDescriptor) Close() {
diff --git a/distribution/pull_v2.go b/distribution/pull_v2.go
index 596d1c1321..ecddc170b7 100644
--- a/distribution/pull_v2.go
+++ b/distribution/pull_v2.go
@@ -278,7 +278,19 @@ func (ld *v2LayerDescriptor) Download(ctx context.Context, progressOutput progre
 		ld.verifier = nil
 		return nil, 0, xfer.DoNotRetry{Err: err}
 	}
-	return tmpFile, size, nil
+
+	// hand off the temporary file to the download manager, so it will only
+	// be closed once
+	ld.tmpFile = nil
+
+	return ioutils.NewReadCloserWrapper(tmpFile, func() error {
+		tmpFile.Close()
+		err := os.RemoveAll(tmpFile.Name())
+		if err != nil {
+			logrus.Errorf("Failed to remove temp file: %s", tmpFile.Name())
+		}
+		return err
+	}), size, nil
 }
 
 func (ld *v2LayerDescriptor) Close() {