On 6/10/25 7:01 AM, Chuck Lever wrote:
On 6/10/25 9:59 AM, Jeff Layton wrote:
On Tue, 2025-06-10 at 09:52 -0400, Chuck Lever wrote:
On 6/10/25 9:50 AM, Jeff Layton wrote:
On Tue, 2025-06-10 at 06:41 -0700, Dai Ngo wrote:
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@xxxxxxxxxx>
---
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.
Oh, I didn't realize that error was mandated, but you're right.
RFC8881, section 8.2.4:
- If the selected table entry does not match the current filehandle,
return NFS4ERR_BAD_STATEID.
I guess we're stuck with reporting that unless we want to amend the
spec.
It is spec-mandated behavior, but we are always free to ignore the
spec. I'm OK with NFS4ERR_INVAL if it results in better behavior
(as long as there is a comment explaining why we deviate from the
mandate).
Since the Linux client does not behave this way I can not test if this
error get us into a loop. I used pynfs to force this behavior.
However, here is the comment in nfs4_do_open:
/*
* BAD_STATEID on OPEN means that the server cancelled our
* state before it received the OPEN_CONFIRM.
* Recover by retrying the request as per the discussion
* on Page 181 of RFC3530.
*/
So it guess BAD_STATEID will get the client and server into a loop.
I'll change error to NFS4ERR_INVAL and add a comment in the code.
-Dai
In any case, whatever we decide:
Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
