Ubuntu
linux-lts-wily package

  1. Bug #1531747
  2. Comment #0

Comment 0 for bug 1531747

Revision history for this message
Serge Hallyn (serge-hallyn) wrote : overlay: mkdir fails if directory exists in lowerdir

If a directory exists in the lowerdir but not in the mounted
overlay, then mkdir of the directory in the target dir results
in a mysterious -EPERM. I've seen this both in wily kernel
(4.2.0-22-generic #27-Ubuntu) and in a hand-built xenial
master-next (with unrelated patches added).

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#!/bin/sh -ex
dir=`mktemp -d`
cleanup() {
 umount -l $dir/t
 rm -rf $dir
}

trap cleanup EXIT

echo "dir is $dir"
mkdir -p $dir/l $dir/u $dir/w $dir/t
mkdir $dir/l/dev
mount -t overlay -o lowerdir=$dir/l,upperdir=$dir/u,workdir=$dir/w o $dir/t
stat $dir/t/dev
rmdir $dir/t/dev
mkdir $dir/t/dev
echo $?
echo "mkdir should have succeeded"
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