SUNRPC: Don't recognize RPC_AUTH_MAXFLAVOR

RPC_AUTH_MAXFLAVOR is an invalid flavor, on purpose.  Don't allow
any processing whatsoever if a caller passes it to rpcauth_create()
or rpcauth_get_gssinfo().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c
index 2bc0cc2196e0..ed2fdd210c0b 100644
--- a/net/sunrpc/auth.c
+++ b/net/sunrpc/auth.c
@@ -82,7 +82,7 @@ MODULE_PARM_DESC(auth_hashtable_size, "RPC credential cache hashtable size");
 
 static u32
 pseudoflavor_to_flavor(u32 flavor) {
-        if (flavor >= RPC_AUTH_MAXFLAVOR)
+        if (flavor > RPC_AUTH_MAXFLAVOR)
                 return RPC_AUTH_GSS;
         return flavor;
 }
@@ -173,6 +173,9 @@ rpcauth_get_gssinfo(rpc_authflavor_t pseudoflavor, struct rpcsec_gss_info *info)
         const struct rpc_authops *ops;
         int result;
 
+        if (flavor >= RPC_AUTH_MAXFLAVOR)
+                return -EINVAL;
+
         ops = auth_flavors[flavor];
         if (ops == NULL)
                 request_module("rpc-auth-%u", flavor);