SUNRPC: remove all refcounting of groupinfo from rpcauth_lookupcred

current_cred() can only be changed by 'current', and
cred->group_info is never changed.  If a new group_info is
needed, a new 'cred' is created.

Consequently it is always safe to access
   current_cred()->group_info

without taking any further references.
So drop the refcounting and the incorrect rcu_dereference().

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c
index 24fcbd23ae6c7e96af1f393f7e1c9a4650dabe1c..383eb919ac0be3ed1348528d59f0bd637cb65bf5 100644 (file)
--- a/net/sunrpc/auth.c
+++ b/net/sunrpc/auth.c
@@ -630,14 +630,8 @@ rpcauth_lookupcred(struct rpc_auth *auth, int flags)
        memset(&acred, 0, sizeof(acred));
        acred.uid = cred->fsuid;
        acred.gid = cred->fsgid;
-       if (flags & RPCAUTH_LOOKUP_RCU)
-               acred.group_info = rcu_dereference(cred->group_info);
-       else
-               acred.group_info = get_group_info(((struct cred *)cred)->group_info);
-
+       acred.group_info = cred->group_info;
        ret = auth->au_ops->lookup_cred(auth, &acred, flags);
-       if (!(flags & RPCAUTH_LOOKUP_RCU))
-               put_group_info(acred.group_info);
        return ret;
 }
 EXPORT_SYMBOL_GPL(rpcauth_lookupcred);