in ovl_clear_empty(), the opaque bit is set on the dir in workingdir in ovl_create_over_whiteout() (the case we're currently looking at) it is also being set in the working dir.
in ovl_rename2(), it is set in two places, on the upper dentries for both the old and new. So it is never set on the lowerdir, at least. I'm still looking, but it may be safe to say that all needed inode checks are already done before we call ovl_set_opaque() so that we can indeed just use prepare_kernel_cred(NULL) instead of prepare_cred(). -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1531747 Title: overlay: mkdir fails if directory exists in lowerdir in a user namespace Status in linux package in Ubuntu: Triaged Status in linux source package in Wily: Triaged Status in linux source package in Xenial: Triaged Bug description: 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). ===================================================== #!/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" ===================================================== The above will work on the host, but fail in a user namespace, i.e in a regular lxd container. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1531747/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
