[1/2] overlay: dentry leak for default_permissions mount option

Commit Message

Eryu Guan June 29, 2016, 1:39 p.m. UTC

overlayfs was leaking dentry on non-directories when using the
'default_permissions' mount option, which resulted in "BUG Dentry
still in use".

The following kernel commit fixed it:
ovl: fix dentry leak for default_permissions

Signed-off-by: Eryu Guan <[e-mail]>
---
 tests/overlay/009     | 68 +++++++++++++++++++++++++++++++++++++++++++++++++++
 tests/overlay/009.out |  2 ++
 tests/overlay/group   |  1 +
 3 files changed, 71 insertions(+)
 create mode 100755 tests/overlay/009
 create mode 100644 tests/overlay/009.out

Patch

diff --git a/tests/overlay/009 b/tests/overlay/009
new file mode 100755
index 0000000..de94ca4
--- /dev/null
+++ b/tests/overlay/009
@@ -0,0 +1,68 @@ 
+#! /bin/bash
+# FS QA Test 009
+#
+# dentry leak for default_permissions mount option
+#
+# This is fixed by kernel commit named as
+# ovl: fix dentry leak for default_permissions
+#
+#-----------------------------------------------------------------------
+# Copyright (c) 2016 Red Hat Inc.  All Rights Reserved.
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it would be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write the Free Software Foundation,
+# Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+#-----------------------------------------------------------------------
+#
+
+seq=`basename $0`
+seqres=$RESULT_DIR/$seq
+echo "QA output created by $seq"
+
+here=`pwd`
+tmp=/tmp/$$
+status=1	# failure is the default!
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+_cleanup()
+{
+	cd /
+	rm -f $tmp.*
+}
+
+# get standard environment, filters and checks
+. ./common/rc
+. ./common/filter
+
+rm -f $seqres.full
+
+# real QA test starts here
+_supported_fs overlay
+_supported_os Linux
+_require_scratch
+
+# Remove all files from previous tests
+_scratch_mkfs
+
+# Create test file in lowerdir
+lowerdir=$SCRATCH_DEV/$OVERLAY_LOWER_DIR
+mkdir -p $lowerdir
+touch $lowerdir/testfile
+
+# mount overlay with default_permissions option, get a reference on the dentry
+_scratch_mount -o default_permissions
+cat $SCRATCH_MNT/testfile
+
+# overlay will be unmounted by test harness and kernel BUG if dentry leaked
+echo "Silence is golden"
+status=0
+exit
diff --git a/tests/overlay/009.out b/tests/overlay/009.out
new file mode 100644
index 0000000..7e97715
--- /dev/null
+++ b/tests/overlay/009.out
@@ -0,0 +1,2 @@ 
+QA output created by 009
+Silence is golden
diff --git a/tests/overlay/group b/tests/overlay/group
index 874bfdd..3f08cd3 100644
--- a/tests/overlay/group
+++ b/tests/overlay/group
@@ -11,3 +11,4 @@ 
 006 auto quick copyup whiteout
 007 auto quick
 008 auto quick whiteout
+009 auto quick