From 98910db2c01d8f7079a44cc8e9c54177e12c943e Mon Sep 17 00:00:00 2001
From: Amit Krishnan <amit.krishnan@oracle.com>
Date: Mon, 14 Mar 2016 13:22:05 -0700
Subject: [PATCH] Remove flush(stdout) in pkg/chrootarchive/diff_unix.go and
 improve error reporting of flush() to fix #21103
 pkg/chrootarchive/diff_unix.go erroneously calls flush on stdout, which tries
 to read from stdout returning an error. This has been fixed by removing the
 call and by modifying flush to return errors and checking for these errors on
 calls to flush.

Signed-off-by: Amit Krishnan <krish.amit@gmail.com>
---
 chrootarchive/archive_unix.go | 5 ++++-
 chrootarchive/diff_unix.go    | 6 ++++--
 chrootarchive/init_unix.go    | 4 ++--
 3 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/chrootarchive/archive_unix.go b/chrootarchive/archive_unix.go
index 51a43f6..9b26856 100644
--- a/chrootarchive/archive_unix.go
+++ b/chrootarchive/archive_unix.go
@@ -46,7 +46,10 @@ func untar() {
 		fatal(err)
 	}
 	// fully consume stdin in case it is zero padded
-	flush(os.Stdin)
+	if _, err := flush(os.Stdin); err != nil {
+		fatal(err)
+	}
+
 	os.Exit(0)
 }
 
diff --git a/chrootarchive/diff_unix.go b/chrootarchive/diff_unix.go
index 4196dd4..a4adb74 100644
--- a/chrootarchive/diff_unix.go
+++ b/chrootarchive/diff_unix.go
@@ -65,8 +65,10 @@ func applyLayer() {
 		fatal(fmt.Errorf("unable to encode layerSize JSON: %s", err))
 	}
 
-	flush(os.Stdout)
-	flush(os.Stdin)
+	if _, err := flush(os.Stdin); err != nil {
+		fatal(err)
+	}
+
 	os.Exit(0)
 }
 
diff --git a/chrootarchive/init_unix.go b/chrootarchive/init_unix.go
index 49fcacc..4f637f1 100644
--- a/chrootarchive/init_unix.go
+++ b/chrootarchive/init_unix.go
@@ -23,6 +23,6 @@ func fatal(err error) {
 
 // flush consumes all the bytes from the reader discarding
 // any errors
-func flush(r io.Reader) {
-	io.Copy(ioutil.Discard, r)
+func flush(r io.Reader) (bytes int64, err error) {
+	return io.Copy(ioutil.Discard, r)
 }