nfsd: deal with revoked delegations appropriately

If a delegation has been revoked by the server, operations using that
delegation should error out with NFS4ERR_DELEG_REVOKED in the >4.1
case, and NFS4ERR_BAD_STATEID otherwise.

The server needs NFSv4.1 clients to explicitly free revoked delegations.
If the server returns NFS4ERR_DELEG_REVOKED, the client will do that;
otherwise it may just forget about the delegation and be unable to
recover when it later sees SEQ4_STATUS_RECALLABLE_STATE_REVOKED set on a
SEQUENCE reply.  That can cause the Linux 4.1 client to loop in its
stage manager.

Signed-off-by: Andrew Elble <aweits@rit.edu>
Reviewed-by: Trond Myklebust <trond.myklebust@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This commit is contained in:
Andrew Elble 2017-11-03 14:06:31 -04:00 committed by J. Bruce Fields
parent 77a08867a6
commit 95da1b3a5a

View File

@ -4016,7 +4016,8 @@ static struct nfs4_delegation *find_deleg_stateid(struct nfs4_client *cl, statei
{
struct nfs4_stid *ret;
ret = find_stateid_by_type(cl, s, NFS4_DELEG_STID);
ret = find_stateid_by_type(cl, s,
NFS4_DELEG_STID|NFS4_REVOKED_DELEG_STID);
if (!ret)
return NULL;
return delegstateid(ret);
@ -4039,6 +4040,12 @@ nfs4_check_deleg(struct nfs4_client *cl, struct nfsd4_open *open,
deleg = find_deleg_stateid(cl, &open->op_delegate_stateid);
if (deleg == NULL)
goto out;
if (deleg->dl_stid.sc_type == NFS4_REVOKED_DELEG_STID) {
nfs4_put_stid(&deleg->dl_stid);
if (cl->cl_minorversion)
status = nfserr_deleg_revoked;
goto out;
}
flags = share_access_to_flags(open->op_share_access);
status = nfs4_check_delegmode(deleg, flags);
if (status) {
@ -4908,6 +4915,16 @@ nfsd4_lookup_stateid(struct nfsd4_compound_state *cstate,
struct nfs4_stid **s, struct nfsd_net *nn)
{
__be32 status;
bool return_revoked = false;
/*
* only return revoked delegations if explicitly asked.
* otherwise we report revoked or bad_stateid status.
*/
if (typemask & NFS4_REVOKED_DELEG_STID)
return_revoked = true;
else if (typemask & NFS4_DELEG_STID)
typemask |= NFS4_REVOKED_DELEG_STID;
if (ZERO_STATEID(stateid) || ONE_STATEID(stateid))
return nfserr_bad_stateid;
@ -4922,6 +4939,12 @@ nfsd4_lookup_stateid(struct nfsd4_compound_state *cstate,
*s = find_stateid_by_type(cstate->clp, stateid, typemask);
if (!*s)
return nfserr_bad_stateid;
if (((*s)->sc_type == NFS4_REVOKED_DELEG_STID) && !return_revoked) {
nfs4_put_stid(*s);
if (cstate->minorversion)
return nfserr_deleg_revoked;
return nfserr_bad_stateid;
}
return nfs_ok;
}