1 files changed, 20 insertions, 6 deletions

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index a885e97dc5f4..6cd86e0fe450 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -3085,10 +3085,11 @@ static __be32
 nfsd4_do_encode_secinfo(struct nfsd4_compoundres *resp,
                          __be32 nfserr, struct svc_export *exp)
 {
-        u32 i, nflavs;
+        u32 i, nflavs, supported;
         struct exp_flavor_info *flavs;
         struct exp_flavor_info def_flavs[2];
-        __be32 *p;
+        __be32 *p, *flavorsp;
+        static bool report = true;
 
         if (nfserr)
                 goto out;
@@ -3112,13 +3113,17 @@ nfsd4_do_encode_secinfo(struct nfsd4_compoundres *resp,
                 }
         }
 
+        supported = 0;
         RESERVE_SPACE(4);
-        WRITE32(nflavs);
+        flavorsp = p++;         /* to be backfilled later */
         ADJUST_ARGS();
+
         for (i = 0; i < nflavs; i++) {
+                rpc_authflavor_t pf = flavs[i].pseudoflavor;
                 struct rpcsec_gss_info info;
 
-                if (rpcauth_get_gssinfo(flavs[i].pseudoflavor, &info) == 0) {
+                if (rpcauth_get_gssinfo(pf, &info) == 0) {
+                        supported++;
                         RESERVE_SPACE(4 + 4 + info.oid.len + 4 + 4);
                         WRITE32(RPC_AUTH_GSS);
                         WRITE32(info.oid.len);
@@ -3126,13 +3131,22 @@ nfsd4_do_encode_secinfo(struct nfsd4_compoundres *resp,
                         WRITE32(info.qop);
                         WRITE32(info.service);
                         ADJUST_ARGS();
-                } else {
+                } else if (pf < RPC_AUTH_MAXFLAVOR) {
+                        supported++;
                         RESERVE_SPACE(4);
-                        WRITE32(flavs[i].pseudoflavor);
+                        WRITE32(pf);
                         ADJUST_ARGS();
+                } else {
+                        if (report)
+                                pr_warn("NFS: SECINFO: security flavor %u "
+                                        "is not supported\n", pf);
                 }
         }
 
+        if (nflavs != supported)
+                report = false;
+        *flavorsp = htonl(supported);
+
 out:
         if (exp)
                 exp_put(exp);