Re: [PATCH 1/1] NFSD: detect mismatch of file handle and delegation stateid in OPEN op
From: Chuck Lever <chuck.lever@oracle.com>
Date: 2025-06-10 13:52:41
On 6/10/25 9:50 AM, Jeff Layton wrote:
On Tue, 2025-06-10 at 06:41 -0700, Dai Ngo wrote:quoted
When the client sends an OPEN with claim type CLAIM_DELEG_CUR_FH or CLAIM_DELEGATION_CUR, the delegation stateid and the file handle must belongs to the same file, otherwise return NFS4ERR_BAD_STATEID. Signed-off-by: Dai Ngo <dai.ngo@oracle.com> --- fs/nfsd/nfs4state.c | 5 +++++ 1 file changed, 5 insertions(+)diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index 59a693f22452..be2ee641a22d 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c@@ -6318,6 +6318,11 @@ nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nf status = nfs4_check_deleg(cl, open, &dp); if (status) goto out; + if (dp && nfsd4_is_deleg_cur(open) && + (dp->dl_stid.sc_file != fp)) { + status = nfserr_bad_stateid; + goto out; + } stp = nfsd4_find_and_lock_existing_open(fp, open); } else { open->op_file = NULL;This seems like a good idea. I wonder if BAD_STATEID is the right error here. It is a valid stateid, after all, it just doesn't match the current_fh. Maybe this should be nfserr_inval ?
I agree, NFS4ERR_BAD_STATEID /might/ cause a loop, so that needs to be tested. BAD_STATEID is mandated by the spec, so if we choose to return a different status code here, it needs a comment explaining why.
In any case, whatever we decide: Reviewed-by: Jeff Layton <jlayton@kernel.org>
-- Chuck Lever