On Thu, 2021-05-13 at 14:35 -0400, Dai Ngo wrote:
> Currently if __nfs4_proc_set_acl fails with NFS4ERR_BADOWNER it
> re-enables the idmapper by clearing NFS_CAP_UIDGID_NOMAP before
> retrying again. The NFS_CAP_UIDGID_NOMAP remains cleared even if
> the retry fails. This causes problem for subsequent setattr
> requests for v4 server that does not have idmapping configured.
>
> Steps to reproduce the problem:
>
> # mount -o vers=4.1,sec=sys server:/export/test /tmp/mnt
> # touch /tmp/mnt/file1
> # chown 99 /tmp/mnt/file1
> # nfs4_setfacl -a A::unknown.user@xxxxxxx:wrtncy /tmp/mnt/file1
> Failed setxattr operation: Invalid argument
> # chown 99 /tmp/mnt/file1
> chown: changing ownership of ‘/tmp/mnt/file1’: Invalid argument
> # umount /tmp/mnt
> # mount -o vers=4.1,sec=sys server:/export/test /tmp/mnt
> # chown 99 /tmp/mnt/file1
> #
>
> Signed-off-by: Dai Ngo <dai.ngo@xxxxxxxxxx>
> ---
> fs/nfs/nfs4proc.c | 9 ++++++++-
> 1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
> index c65c4b41e2c1..e12630e3bb7c 100644
> --- a/fs/nfs/nfs4proc.c
> +++ b/fs/nfs/nfs4proc.c
> @@ -5926,13 +5926,20 @@ static int __nfs4_proc_set_acl(struct inode
> *inode, const void *buf, size_t bufl
> static int nfs4_proc_set_acl(struct inode *inode, const void *buf,
> size_t buflen)
> {
> struct nfs4_exception exception = { };
> - int err;
> + struct nfs_server *server = NFS_SERVER(inode);
> + int err, nomap;
> +
> + nomap = server->caps & NFS_CAP_UIDGID_NOMAP;
> do {
> err = __nfs4_proc_set_acl(inode, buf, buflen);
> trace_nfs4_set_acl(inode, err);
> err = nfs4_handle_exception(NFS_SERVER(inode), err,
> &exception);
> } while (exception.retry);
> +
> + /* if retry still fails then restore NFS_CAP_UIDGID_NOMAP
> setting */
> + if (err && nomap)
> + server->caps |= NFS_CAP_UIDGID_NOMAP;
If the server returns NFS4ERR_BADOWNER or NFS4ERR_BADNAME, why even
call nfs4_handle_exception()? There is nothing the kernel can do about
it, and changing the value of NFS_CAP_UIDGID_NOMAP isn't going to help
because the kernel isn't involved in encoding the ACEs.
IOW: Why not just exit with an appropriate error (-EINVAL perhaps?)
immediately.
> return err;
> }
>
--
Trond Myklebust
Linux NFS client maintainer, Hammerspace
trond.myklebust@xxxxxxxxxxxxxxx
