On Tue, Sep 17, 2019 at 3:26 PM Miklos Szeredi <miklos@xxxxxxxxxx> wrote:
>
> On Tue, Sep 17, 2019 at 11:37 AM Thomas Lange
> <lange@xxxxxxxxxxxxxxxxxxxxxxx> wrote:
> >
> > >>>>> On Tue, 17 Sep 2019 10:10:11 +0200, Miklos Szeredi <miklos@xxxxxxxxxx> said:
> >
> > > This is most probably about nfs4 acl support. Does "noacl" export
> > > option fix it?
> > Unfortunately it's not possible to disable acl support for NFS v4 (only in Debian?).
> > That's what I read in some articles.
> >
> > I've added no_acl to the exports line:
> > # exportfs -v
> > /files/scratch 134.95.9.128/25(ro,async,wdelay,no_root_squash,no_subtree_check,no_acl,sec=sys,ro,secure,no_root_squash,no_all_squash)
> >
> > But this command does not show the no_acl option:
> >
> > # cat /proc/fs/nfs/exports
> > # Version 1.1
> > # Path Client(Flags) # IPs
> > /files 134.95.9.128/25(ro,no_root_squash,sync,no_wdelay,no_subtree_check,v4root,uuid=9d4520b3:676a426f:92251f2f:b0e40f3b,sec=390003:390004:390005:1)
> > / 134.95.9.128/25(ro,no_root_squash,sync,no_wdelay,no_subtree_check,v4root,fsid=0,uuid=9d4520b3:676a426f:92251f2f:b0e40f3b,sec=390003:390004:390005:1)
> > /files/scratch 134.95.9.128/25(ro,no_root_squash,async,wdelay,no_subtree_check,uuid=9d4520b3:676a426f:92251f2f:b0e40f3b,sec=1)
> >
> >
> > I've also added -onoacl the the mount command on client side. Still the
> > same results, when I want to write to a file in overlayfs
> >
> > 13415 openat(AT_FDCWD, "/b/merged/etc/test1", O_WRONLY|O_CREAT|O_TRUNC, 0666) = -1 EOPNOTSUPP (Operation not supported)
> >
> >
> > I've checked the access to the "original" file in the lower (NFS v4
> > mounted) directory, by checking the results of getfacl and nfs4_getfacl.
> >
> >
> > NFS v3, exportfs with no_acl
> > ============================
> > + strace -etrace=getxattr getfacl /b/lower/etc/test1
> > getxattr("/b/lower/etc/test1", "system.posix_acl_access", 0x7ffcb6b56160, 132) = -1 EOPNOTSUPP (Operation not supported)
> > getfacl: Removing leading '/' from absolute path names
> >
> > suenner[~]# strace -etrace=getxattr nfs4_getfacl /b/lower/etc/test1
> > getxattr("/b/lower/etc/test1", "system.nfs4_acl", NULL, 0) = -1 EOPNOTSUPP (Operation not supported)
> >
> >
> >
> > NFS v4 using mount -onoacl, exportfs with no_acl
> > ================================================
> >
> > + strace -etrace=getxattr getfacl /b/lower/etc/test1
> > getxattr("/b/lower/etc/test1", "system.posix_acl_access", 0x7fff39fd9cd0, 132) = -1 EOPNOTSUPP (Operation not supported)
> >
> >
> > + strace -etrace=getxattr nfs4_getfacl /b/lower/etc/test1
> > getxattr("/b/lower/etc/test1", "system.nfs4_acl", NULL, 0) = 80
> > getxattr("/b/lower/etc/test1", "system.nfs4_acl", "\0\0\0\3\0\0\0\0\0\0\0\0\0\26\1\207\0\0\0\6OWNER@\0\0\0\0\0", 80) = 80
> >
> >
> > This shows that disabling ACL in NFS v4 does not work.
> > Does this disturb the behaviour of overlayfs?
>
> The problem is that overlayfs tries to copy-up the system.nfs4_acl,
> but fails (no other filesystem supports this xattr). Similar thing
> happens with "cp --preserv=xattr".
>
> Looking back...
>
> https://lore.kernel.org/linux-fsdevel/CAHpGcMKHjic6L+J0qvMYNG9hVCcDO1hEpx4BiEk0ZCKDV39BmA@xxxxxxxxxxxxxx/
The other thread discussing this issue:
https://lore.kernel.org/linux-nfs/f74fae81-d1bc-1c0e-7b41-69502bd7c489@xxxxxxx/
Thanks,
Miklos
