nfsd: nfsd4_spo_must_allow() must check this is a v4 compound request

JIRA: https://issues.redhat.com/browse/RHEL-82689

commit 1244f0b
Author: NeilBrown <neil@brown.name>
Date:   Fri Mar 28 11:05:59 2025 +1100

    nfsd: nfsd4_spo_must_allow() must check this is a v4 compound request

    If the request being processed is not a v4 compound request, then
    examining the cstate can have undefined results.

    This patch adds a check that the rpc procedure being executed
    (rq_procinfo) is the NFSPROC4_COMPOUND procedure.

    Reported-by: Olga Kornievskaia <okorniev@redhat.com>
    Cc: stable@vger.kernel.org
    Reviewed-by: Jeff Layton <jlayton@kernel.org>
    Signed-off-by: NeilBrown <neil@brown.name>
    Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

Signed-off-by: Olga Kornievskaia <okorniev@redhat.com>

Author: Olga Kornievskaia

fs/nfsd/nfs4proc.c

@@ -3763,7 +3763,8 @@ bool nfsd4_spo_must_allow(struct svc_rqst *rqstp)
 	struct nfs4_op_map *allow = &cstate->clp->cl_spo_must_allow;
 	u32 opiter;
 
-	if (!cstate->minorversion)
+	if (rqstp->rq_procinfo != &nfsd_version4.vs_proc[NFSPROC4_COMPOUND] ||
+	    cstate->minorversion == 0)
 		return false;
 
 	if (cstate->spo_must_allowed)