From: Sergey Bashirov Date: Mon, 25 Aug 2025 13:11:02 +0000 (+0300) Subject: NFSD: Disallow layoutget during grace period X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=db155b7c7c85b5f14edec21e164001a168581ffb;p=users%2Fhch%2Fmisc.git NFSD: Disallow layoutget during grace period When the server is recovering from a reboot and is in a grace period, any operation that may result in deletion or reallocation of block extents should not be allowed. See RFC 8881, section 18.43.3. If multiple clients write data to the same file, rebooting the server during writing may result in file corruption. In the worst case, the exported XFS may also become corrupted. Observed this behavior while testing pNFS block volume setup. Co-developed-by: Konstantin Evtushenko Signed-off-by: Konstantin Evtushenko Signed-off-by: Sergey Bashirov Signed-off-by: Chuck Lever --- diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c index d7c58aa64f06..2dc8910f8f72 100644 --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -2435,6 +2435,7 @@ static __be32 nfsd4_layoutget(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, union nfsd4_op_u *u) { + struct net *net = SVC_NET(rqstp); struct nfsd4_layoutget *lgp = &u->layoutget; struct svc_fh *current_fh = &cstate->current_fh; const struct nfsd4_layout_ops *ops; @@ -2486,6 +2487,10 @@ nfsd4_layoutget(struct svc_rqst *rqstp, if (lgp->lg_seg.length == 0) goto out; + nfserr = nfserr_grace; + if (locks_in_grace(net)) + goto out; + nfserr = nfsd4_preprocess_layout_stateid(rqstp, cstate, &lgp->lg_sid, true, lgp->lg_layout_type, &ls); if (nfserr) {