Re: [PATCH RFC 11/24] nfsd: allow DELEGRETURN on directories

[Chuck Lever]

On Fri, Mar 15, 2024 at 12:53:02PM -0400, Jeff Layton wrote:
> fh_verify only allows you to filter on a single type of inode, so have
> nfsd4_delegreturn not filter by type. Once fh_verify returns, do the
> appropriate check of the type and return an error if it's not a regular
> file or directory.
> 
> Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
> ---
>  fs/nfsd/nfs4state.c | 14 +++++++++++++-
>  1 file changed, 13 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> index 17d09d72632b..c52e807f9672 100644
> --- a/fs/nfsd/nfs4state.c
> +++ b/fs/nfsd/nfs4state.c
> @@ -7425,12 +7425,24 @@ nfsd4_delegreturn(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
>  	struct nfs4_delegation *dp;
>  	stateid_t *stateid = &dr->dr_stateid;
>  	struct nfs4_stid *s;
> +	umode_t mode;
>  	__be32 status;
>  	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
>  
> -	if ((status = fh_verify(rqstp, &cstate->current_fh, S_IFREG, 0)))
> +	if ((status = fh_verify(rqstp, &cstate->current_fh, 0, 0)))
>  		return status;
>  
> +	mode = d_inode(cstate->current_fh.fh_dentry)->i_mode & S_IFMT;
> +	switch(mode) {
> +	case S_IFREG:
> +	case S_IFDIR:
> +		break;
> +	case S_IFLNK:
> +		return nfserr_symlink;
> +	default:
> +		return nfserr_inval;
> +	}
> +

RFC 8881 Section 15.2 does not list NFS4ERR_SYMLINK among the
valid status codes for the DELEGRETURN operation. Maybe the naked
fh_verify() call has gotten it wrong all these years...?


>  	status = nfsd4_lookup_stateid(cstate, stateid, SC_TYPE_DELEG, 0, &s, nn);
>  	if (status)
>  		goto out;
> 
> -- 
> 2.44.0
> 

-- 
Chuck Lever