[PATCH] nfsd: Fix nfs4_disable_idmapping option

["Pali Rohár" <pali@kernel.org>]

NFSv4 server option nfs4_disable_idmapping says that it turn off server's
NFSv4 idmapping when using 'sec=sys'. But it also turns idmapping off also
for 'sec=none'.

NFSv4 client option nfs4_disable_idmapping says same thing and really it
turns the NFSv4 idmapping only for 'sec=sys'.

Fix the NFSv4 server option nfs4_disable_idmapping to turn off idmapping
only for 'sec=sys'. This aligns the server nfs4_disable_idmapping option
with its description and also aligns behavior with the client option.

Signed-off-by: Pali Rohár <pali@kernel.org>
Cc: stable@vger.kernel.org
---
 fs/nfsd/nfs4idmap.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/nfsd/nfs4idmap.c b/fs/nfsd/nfs4idmap.c
index 7a806ac13e31..641293711f53 100644
--- a/fs/nfsd/nfs4idmap.c
+++ b/fs/nfsd/nfs4idmap.c
@@ -620,7 +620,7 @@ numeric_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namel
 static __be32
 do_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, u32 *id)
 {
-	if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor < RPC_AUTH_GSS)
+	if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor == RPC_AUTH_UNIX)
 		if (numeric_name_to_id(rqstp, type, name, namelen, id))
 			return 0;
 		/*
@@ -633,7 +633,7 @@ do_name_to_id(struct svc_rqst *rqstp, int type, const char *name, u32 namelen, u
 static __be32 encode_name_from_id(struct xdr_stream *xdr,
 				  struct svc_rqst *rqstp, int type, u32 id)
 {
-	if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor < RPC_AUTH_GSS)
+	if (nfs4_disable_idmapping && rqstp->rq_cred.cr_flavor == RPC_AUTH_UNIX)
 		return encode_ascii_id(xdr, id);
 	return idmap_id_to_name(xdr, rqstp, type, id);
 }
-- 
2.20.1