[PATCH 1/2] common/rc: introduce _overlay_mount_dirs helper

[PATCH 1/2] common/rc: introduce _overlay_mount_dirs helper

[Eryu Guan]

Introduce a new _overlay_mount_dirs() helper to do the actual
overlay mount operation and factor _overlay_scratch_mount and
_overlay_mount code to use a single implemention of
_overlay_mount_dirs(). Also convert all bare mount of overlay in
tests to use it.

Suggested-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Eryu Guan <eguan@redhat.com>
---
 common/rc         | 21 +++++++++++++++------
 tests/overlay/005 |  6 ++----
 tests/overlay/010 |  5 ++---
 3 files changed, 19 insertions(+), 13 deletions(-)

diff --git a/common/rc b/common/rc
index b19b698..6c1c3ff 100644
--- a/common/rc
+++ b/common/rc
@@ -266,6 +266,18 @@ _scratch_mount_options()
 					$SCRATCH_DEV $SCRATCH_MNT
 }
 
+# helper function to do the actual overlayfs mount operation
+_overlay_mount_dirs()
+{
+	local lowerdir=$1
+	local upperdir=$2
+	local workdir=$3
+	shift 3
+
+	$MOUNT_PROG -t overlay -o lowerdir=$lowerdir -o upperdir=$upperdir \
+		    -o workdir=$workdir $*
+}
+
 # Given a dir, set up 3 subdirectories and mount on the given mnt.
 # The dir is used as the mount device so it can be seen from df or mount
 _overlay_mount()
@@ -293,12 +305,9 @@ _overlay_mount()
 	mkdir -p $dir/$OVERLAY_LOWER_DIR
 	mkdir -p $dir/$OVERLAY_WORK_DIR
 
-	$MOUNT_PROG -t overlay $SELINUX_MOUNT_OPTIONS \
-		    -o lowerdir=$dir/$OVERLAY_LOWER_DIR \
-		    -o upperdir=$dir/$OVERLAY_UPPER_DIR \
-		    -o workdir=$dir/$OVERLAY_WORK_DIR   \
-		    $OVERLAY_MOUNT_OPTIONS $* \
-		    $dir $mnt
+	_overlay_mount_dirs $dir/$OVERLAY_LOWER_DIR $dir/$OVERLAY_UPPER_DIR \
+			    $dir/$OVERLAY_WORK_DIR $OVERLAY_MOUNT_OPTIONS $* \
+			    $dir $mnt
 }
 
 _overlay_test_mount()
diff --git a/tests/overlay/005 b/tests/overlay/005
index 495e7b5..522c6f0 100755
--- a/tests/overlay/005
+++ b/tests/overlay/005
@@ -93,10 +93,8 @@ $XFS_IO_PROG -f -c "truncate 48m" ${lowerd}/test_file \
 	>>$seqres.full 2>&1
 
 # mount new overlayfs
-$MOUNT_PROG -t overlay $SELINUX_MOUNT_OPTIONS \
-	    -o lowerdir=$lowerd -o upperdir=$upperd \
-	    -o workdir=$workd \
-	    $SCRATCH_DEV $SCRATCH_MNT
+_overlay_mount_dirs $lowerd $upperd $workd $SELINUX_MOUNT_OPTIONS \
+		    $SCRATCH_DEV $SCRATCH_MNT
 
 # the open call triggers copy-up and it will fail ENOSPC
 $XFS_IO_PROG -f -c "o" ${SCRATCH_MNT}/test_file \
diff --git a/tests/overlay/010 b/tests/overlay/010
index 5d1c2bd..a302d74 100755
--- a/tests/overlay/010
+++ b/tests/overlay/010
@@ -67,9 +67,8 @@ touch $lowerdir1/testdir/a $lowerdir1/testdir/b
 mknod $lowerdir2/testdir/a c 0 0
 
 # Mount overlayfs and remove testdir, which led to kernel crash
-$MOUNT_PROG -t overlay -o lowerdir=$lowerdir2:$lowerdir1 \
-	    -o upperdir=$upperdir,workdir=$workdir \
-	    $SCRATCH_DEV $SCRATCH_MNT
+_overlay_mount_dirs "$lowerdir2:$lowerdir1" $upperdir $workdir \
+		    $SCRATCH_DEV $SCRATCH_MNT
 rm -rf $SCRATCH_MNT/testdir
 
 # success, all done
-- 
2.7.4

[PATCH v2 2/2] overlay: copy-up lowerdir which has opaque xattr set

[Eryu Guan]

When copying up a directory with opaque xattr set, the xattr was
copied up as well, after a remount the opaque flag is honored so the
copied-up directory is treated as opaque, which causes files created
in the lowerdir to be hidden when using multiple lower directories.

This is fixed by "ovl: don't copy up opaqueness".

Signed-off-by: Eryu Guan <eguan@redhat.com>
---
v2:
- use _overlay_mount_dirs helper to do the overlay mount
- use _scratch_unmount instead of raw $UMOUNT_PROG
- remove unused _require_attrs

 tests/overlay/014     | 92 +++++++++++++++++++++++++++++++++++++++++++++++++++
 tests/overlay/014.out |  3 ++
 tests/overlay/group   |  1 +
 3 files changed, 96 insertions(+)
 create mode 100755 tests/overlay/014
 create mode 100644 tests/overlay/014.out

diff --git a/tests/overlay/014 b/tests/overlay/014
new file mode 100755
index 0000000..510f0cd
--- /dev/null
+++ b/tests/overlay/014
@@ -0,0 +1,92 @@
+#! /bin/bash
+# FS QA Test 014
+#
+# Test copy-up of lowerdir with opaque xattr set.
+#
+# When copying up a directory with opaque xattr set, the xattr was copied up as
+# well, after a remount the opaque flag is honored so the copied-up directory
+# is treated as opaque, which causes files created in the lowerdir to be hidden
+# when using multiple lower directories.
+#
+# This is fixed by "ovl: don't copy up opaqueness".
+#
+#-----------------------------------------------------------------------
+# 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
+. ./common/attr
+
+# remove previous $seqres.full before test
+rm -f $seqres.full
+
+# real QA test starts here
+_supported_fs overlay
+_supported_os Linux
+_require_test
+_require_scratch
+
+# Remove all files from previous tests
+_scratch_mkfs
+
+# Create multiple lowerdirs and upperdir, workdir, and testdir on lowerdir
+lowerdir1=$SCRATCH_DEV/lower1
+lowerdir2=$SCRATCH_DEV/lower2
+upperdir=$SCRATCH_DEV/upper
+workdir=$SCRATCH_DEV/workdir
+mkdir -p $lowerdir1 $lowerdir2 $upperdir $workdir
+mkdir -p $lowerdir1/testdir/d
+
+# mount overlay with $lowerdir2 as upperdir, and remove & recreate testdir,
+# make testdir on $lowerdir2 opaque
+_overlay_mount_dirs $lowerdir1 $lowerdir2 $workdir none $SCRATCH_MNT
+rm -rf $SCRATCH_MNT/testdir
+mkdir -p $SCRATCH_MNT/testdir/visibledir
+_scratch_unmount
+
+# mount overlay again, with lowerdir1 and lowerdir2 as multiple lowerdirs,
+# and create a new file in testdir, triggers copyup from lowerdir,
+# copyup should not copy overlayfs private xattr
+_overlay_mount_dirs "$lowerdir2:$lowerdir1" $upperdir $workdir none $SCRATCH_MNT
+touch $SCRATCH_MNT/testdir/visiblefile
+
+# umount and mount overlay again, buggy kernel treats the copied-up dir as
+# opaque, visibledir is not seen in merged dir.
+_scratch_unmount
+_overlay_mount_dirs "$lowerdir2:$lowerdir1" $upperdir $workdir none $SCRATCH_MNT
+ls $SCRATCH_MNT/testdir
+
+# success, all done
+status=0
+exit
diff --git a/tests/overlay/014.out b/tests/overlay/014.out
new file mode 100644
index 0000000..ec09c4d
--- /dev/null
+++ b/tests/overlay/014.out
@@ -0,0 +1,3 @@
+QA output created by 014
+visibledir
+visiblefile
diff --git a/tests/overlay/group b/tests/overlay/group
index 5c80566..71eaadb 100644
--- a/tests/overlay/group
+++ b/tests/overlay/group
@@ -16,3 +16,4 @@
 011 auto quick
 012 auto quick
 013 auto quick
+014 auto quick copyup
-- 
2.7.4

Re: [PATCH 1/2] common/rc: introduce _overlay_mount_dirs helper

[Eryu Guan]

On Tue, Aug 09, 2016 at 07:16:20PM +0800, Eryu Guan wrote:
> Introduce a new _overlay_mount_dirs() helper to do the actual
> overlay mount operation and factor _overlay_scratch_mount and
> _overlay_mount code to use a single implemention of
> _overlay_mount_dirs(). Also convert all bare mount of overlay in
> tests to use it.
> 
> Suggested-by: Dave Chinner <dchinner@redhat.com>
> Signed-off-by: Eryu Guan <eguan@redhat.com>

Ping on this one, hope I can push this out this week.

Thanks,
Eryu

Re: [PATCH 1/2] common/rc: introduce _overlay_mount_dirs helper

[Eryu Guan]

On Fri, Aug 12, 2016 at 11:33:42AM +0800, Eryu Guan wrote:
> On Tue, Aug 09, 2016 at 07:16:20PM +0800, Eryu Guan wrote:
> > Introduce a new _overlay_mount_dirs() helper to do the actual
> > overlay mount operation and factor _overlay_scratch_mount and
> > _overlay_mount code to use a single implemention of
> > _overlay_mount_dirs(). Also convert all bare mount of overlay in
> > tests to use it.
> > 
> > Suggested-by: Dave Chinner <dchinner@redhat.com>
> > Signed-off-by: Eryu Guan <eguan@redhat.com>
> 
> Ping on this one, hope I can push this out this week.

Ping again.

Thanks,
Eryu

Re: [PATCH 1/2] common/rc: introduce _overlay_mount_dirs helper

[Eryu Guan]

On Fri, Aug 19, 2016 at 11:05:17AM +0800, Eryu Guan wrote:
> On Fri, Aug 12, 2016 at 11:33:42AM +0800, Eryu Guan wrote:
> > On Tue, Aug 09, 2016 at 07:16:20PM +0800, Eryu Guan wrote:
> > > Introduce a new _overlay_mount_dirs() helper to do the actual
> > > overlay mount operation and factor _overlay_scratch_mount and
> > > _overlay_mount code to use a single implemention of
> > > _overlay_mount_dirs(). Also convert all bare mount of overlay in
> > > tests to use it.
> > > 
> > > Suggested-by: Dave Chinner <dchinner@redhat.com>
> > > Signed-off-by: Eryu Guan <eguan@redhat.com>
> > 
> > Ping on this one, hope I can push this out this week.
> 
> Ping again.

Ping for the third time :)

Thanks,
Eryu

Re: [PATCH 1/2] common/rc: introduce _overlay_mount_dirs helper

[Eryu Guan]

Hi all,

On Thu, Aug 25, 2016 at 12:11:11PM +0800, Eryu Guan wrote:
> On Fri, Aug 19, 2016 at 11:05:17AM +0800, Eryu Guan wrote:
> > On Fri, Aug 12, 2016 at 11:33:42AM +0800, Eryu Guan wrote:
> > > On Tue, Aug 09, 2016 at 07:16:20PM +0800, Eryu Guan wrote:
> > > > Introduce a new _overlay_mount_dirs() helper to do the actual
> > > > overlay mount operation and factor _overlay_scratch_mount and
> > > > _overlay_mount code to use a single implemention of
> > > > _overlay_mount_dirs(). Also convert all bare mount of overlay in
> > > > tests to use it.
> > > > 
> > > > Suggested-by: Dave Chinner <dchinner@redhat.com>
> > > > Signed-off-by: Eryu Guan <eguan@redhat.com>
> > > 
> > > Ping on this one, hope I can push this out this week.
> > 
> > Ping again.
> 
> Ping for the third time :)

I have trouble getting my patches reviewed. Could someone help review
this patchset? Thanks a lot!

Eryu

Re: [PATCH 1/2] common/rc: introduce _overlay_mount_dirs helper

[Dave Chinner]

On Tue, Aug 09, 2016 at 07:16:20PM +0800, Eryu Guan wrote:
> Introduce a new _overlay_mount_dirs() helper to do the actual
> overlay mount operation and factor _overlay_scratch_mount and
> _overlay_mount code to use a single implemention of
> _overlay_mount_dirs(). Also convert all bare mount of overlay in
> tests to use it.
> 
> Suggested-by: Dave Chinner <dchinner@redhat.com>
> Signed-off-by: Eryu Guan <eguan@redhat.com>
> ---
>  common/rc         | 21 +++++++++++++++------
>  tests/overlay/005 |  6 ++----
>  tests/overlay/010 |  5 ++---
>  3 files changed, 19 insertions(+), 13 deletions(-)
> 
> diff --git a/common/rc b/common/rc
> index b19b698..6c1c3ff 100644
> --- a/common/rc
> +++ b/common/rc
> @@ -266,6 +266,18 @@ _scratch_mount_options()
>  					$SCRATCH_DEV $SCRATCH_MNT
>  }
>  
> +# helper function to do the actual overlayfs mount operation
> +_overlay_mount_dirs()
> +{
> +	local lowerdir=$1
> +	local upperdir=$2
> +	local workdir=$3
> +	shift 3
> +
> +	$MOUNT_PROG -t overlay -o lowerdir=$lowerdir -o upperdir=$upperdir \
> +		    -o workdir=$workdir $*
> +}
> +
>  # Given a dir, set up 3 subdirectories and mount on the given mnt.
>  # The dir is used as the mount device so it can be seen from df or mount
>  _overlay_mount()
> @@ -293,12 +305,9 @@ _overlay_mount()
>  	mkdir -p $dir/$OVERLAY_LOWER_DIR
>  	mkdir -p $dir/$OVERLAY_WORK_DIR
>  
> -	$MOUNT_PROG -t overlay $SELINUX_MOUNT_OPTIONS \
> -		    -o lowerdir=$dir/$OVERLAY_LOWER_DIR \
> -		    -o upperdir=$dir/$OVERLAY_UPPER_DIR \
> -		    -o workdir=$dir/$OVERLAY_WORK_DIR   \
> -		    $OVERLAY_MOUNT_OPTIONS $* \
> -		    $dir $mnt
> +	_overlay_mount_dirs $dir/$OVERLAY_LOWER_DIR $dir/$OVERLAY_UPPER_DIR \
> +			    $dir/$OVERLAY_WORK_DIR $OVERLAY_MOUNT_OPTIONS $* \
> +			    $dir $mnt

This drops SELINUX_MOUNT_OPTIONS from the mount options. I'd suggest
this option should be moved inside _overlay_mount_dirs() so they are
always applied to overlayfs mounts if set.

Cheers,

Dave.
-- 
Dave Chinner
david@fromorbit.com

Re: [PATCH v2 2/2] overlay: copy-up lowerdir which has opaque xattr set

[Dave Chinner]

On Tue, Aug 09, 2016 at 07:16:21PM +0800, Eryu Guan wrote:
> When copying up a directory with opaque xattr set, the xattr was
> copied up as well, after a remount the opaque flag is honored so the
> copied-up directory is treated as opaque, which causes files created
> in the lowerdir to be hidden when using multiple lower directories.
> 
> This is fixed by "ovl: don't copy up opaqueness".
....
> +_scratch_mkfs
> +
> +# Create multiple lowerdirs and upperdir, workdir, and testdir on lowerdir
> +lowerdir1=$SCRATCH_DEV/lower1
> +lowerdir2=$SCRATCH_DEV/lower2
> +upperdir=$SCRATCH_DEV/upper
> +workdir=$SCRATCH_DEV/workdir
> +mkdir -p $lowerdir1 $lowerdir2 $upperdir $workdir
> +mkdir -p $lowerdir1/testdir/d
> +
> +# mount overlay with $lowerdir2 as upperdir, and remove & recreate testdir,
> +# make testdir on $lowerdir2 opaque
> +_overlay_mount_dirs $lowerdir1 $lowerdir2 $workdir none $SCRATCH_MNT

What is the "none" here? If _overlay_mount_dirs() doesn't require
this parameter to have a specifically valid value, then why are
we passing it in at all?

Cheers,

Dave.
-- 
Dave Chinner
david@fromorbit.com

Re: [PATCH 1/2] common/rc: introduce _overlay_mount_dirs helper

[Eryu Guan]

On Thu, Sep 01, 2016 at 10:16:29AM +1000, Dave Chinner wrote:
> On Tue, Aug 09, 2016 at 07:16:20PM +0800, Eryu Guan wrote:
> > Introduce a new _overlay_mount_dirs() helper to do the actual
> > overlay mount operation and factor _overlay_scratch_mount and
> > _overlay_mount code to use a single implemention of
> > _overlay_mount_dirs(). Also convert all bare mount of overlay in
> > tests to use it.
> > 
> > Suggested-by: Dave Chinner <dchinner@redhat.com>
> > Signed-off-by: Eryu Guan <eguan@redhat.com>
> > ---
> >  common/rc         | 21 +++++++++++++++------
> >  tests/overlay/005 |  6 ++----
> >  tests/overlay/010 |  5 ++---
> >  3 files changed, 19 insertions(+), 13 deletions(-)
> > 
> > diff --git a/common/rc b/common/rc
> > index b19b698..6c1c3ff 100644
> > --- a/common/rc
> > +++ b/common/rc
> > @@ -266,6 +266,18 @@ _scratch_mount_options()
> >  					$SCRATCH_DEV $SCRATCH_MNT
> >  }
> >  
> > +# helper function to do the actual overlayfs mount operation
> > +_overlay_mount_dirs()
> > +{
> > +	local lowerdir=$1
> > +	local upperdir=$2
> > +	local workdir=$3
> > +	shift 3
> > +
> > +	$MOUNT_PROG -t overlay -o lowerdir=$lowerdir -o upperdir=$upperdir \
> > +		    -o workdir=$workdir $*
> > +}
> > +
> >  # Given a dir, set up 3 subdirectories and mount on the given mnt.
> >  # The dir is used as the mount device so it can be seen from df or mount
> >  _overlay_mount()
> > @@ -293,12 +305,9 @@ _overlay_mount()
> >  	mkdir -p $dir/$OVERLAY_LOWER_DIR
> >  	mkdir -p $dir/$OVERLAY_WORK_DIR
> >  
> > -	$MOUNT_PROG -t overlay $SELINUX_MOUNT_OPTIONS \
> > -		    -o lowerdir=$dir/$OVERLAY_LOWER_DIR \
> > -		    -o upperdir=$dir/$OVERLAY_UPPER_DIR \
> > -		    -o workdir=$dir/$OVERLAY_WORK_DIR   \
> > -		    $OVERLAY_MOUNT_OPTIONS $* \
> > -		    $dir $mnt
> > +	_overlay_mount_dirs $dir/$OVERLAY_LOWER_DIR $dir/$OVERLAY_UPPER_DIR \
> > +			    $dir/$OVERLAY_WORK_DIR $OVERLAY_MOUNT_OPTIONS $* \
> > +			    $dir $mnt
> 
> This drops SELINUX_MOUNT_OPTIONS from the mount options. I'd suggest

This is unexpected, it's dropped by mistake..

> this option should be moved inside _overlay_mount_dirs() so they are
> always applied to overlayfs mounts if set.

Sure, will do.

Thanks a lot for the review!

Eryu

Re: [PATCH v2 2/2] overlay: copy-up lowerdir which has opaque xattr set

[Eryu Guan]

On Thu, Sep 01, 2016 at 10:22:41AM +1000, Dave Chinner wrote:
> On Tue, Aug 09, 2016 at 07:16:21PM +0800, Eryu Guan wrote:
> > When copying up a directory with opaque xattr set, the xattr was
> > copied up as well, after a remount the opaque flag is honored so the
> > copied-up directory is treated as opaque, which causes files created
> > in the lowerdir to be hidden when using multiple lower directories.
> > 
> > This is fixed by "ovl: don't copy up opaqueness".
> ....
> > +_scratch_mkfs
> > +
> > +# Create multiple lowerdirs and upperdir, workdir, and testdir on lowerdir
> > +lowerdir1=$SCRATCH_DEV/lower1
> > +lowerdir2=$SCRATCH_DEV/lower2
> > +upperdir=$SCRATCH_DEV/upper
> > +workdir=$SCRATCH_DEV/workdir
> > +mkdir -p $lowerdir1 $lowerdir2 $upperdir $workdir
> > +mkdir -p $lowerdir1/testdir/d
> > +
> > +# mount overlay with $lowerdir2 as upperdir, and remove & recreate testdir,
> > +# make testdir on $lowerdir2 opaque
> > +_overlay_mount_dirs $lowerdir1 $lowerdir2 $workdir none $SCRATCH_MNT
> 
> What is the "none" here? If _overlay_mount_dirs() doesn't require
> this parameter to have a specifically valid value, then why are
> we passing it in at all?

It's place-holder for device to be mounted, for overlayfs this can be
any string but cannot be omitted. I probably should use $SCRATCH_DEV
instead, like what _scratch_mount does on overlayfs, so helpers like
_fs_type and _df_device that look for mounted device could work
correctly.

Thanks for the review!

Eryu