SUNRPC: Fix RPCAUTH_LOOKUP_ROOTCREDS

The current RPCAUTH_LOOKUP_ROOTCREDS flag only works for AUTH_SYS
authentication, and then only as a special case in the code. This patch
removes the auth_sys special casing, and replaces it with generic code.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

4 files changed, 49 insertions, 50 deletions

diff --git a/include/linux/sunrpc/auth.h b/include/linux/sunrpc/auth.h
index 84d5f3a05b16..012566a6257b 100644
--- a/include/linux/sunrpc/auth.h
+++ b/include/linux/sunrpc/auth.h
@@ -89,7 +89,6 @@ struct rpc_auth {
 
 /* Flags for rpcauth_lookupcred() */
 #define RPCAUTH_LOOKUP_NEW              0x01    /* Accept an uninitialised cred */
-#define RPCAUTH_LOOKUP_ROOTCREDS        0x02    /* This really ought to go! */
 
 /*
  * Client authentication ops
@@ -136,7 +135,8 @@ void			rpcauth_release(struct rpc_auth *);
 struct rpc_cred *       rpcauth_lookup_credcache(struct rpc_auth *, struct auth_cred *, int);
 void                    rpcauth_init_cred(struct rpc_cred *, const struct auth_cred *, struct rpc_auth *, const struct rpc_credops *);
 struct rpc_cred *       rpcauth_lookupcred(struct rpc_auth *, int);
-struct rpc_cred *       rpcauth_bindcred(struct rpc_task *);
+void                    rpcauth_bindcred(struct rpc_task *);
+void                    rpcauth_bind_root_cred(struct rpc_task *);
 void                    rpcauth_holdcred(struct rpc_task *);
 void                    put_rpccred(struct rpc_cred *);
 void                    rpcauth_unbindcred(struct rpc_task *);
diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c
index b38f6ee2f5e2..b0f2b2ee7cc0 100644
--- a/net/sunrpc/auth.c
+++ b/net/sunrpc/auth.c
@@ -285,9 +285,6 @@ rpcauth_lookup_credcache(struct rpc_auth *auth, struct auth_cred * acred,
 
         nr = hash_long(acred->uid, RPC_CREDCACHE_HASHBITS);
 
-        if (!(flags & RPCAUTH_LOOKUP_ROOTCREDS))
-                nr = acred->uid & RPC_CREDCACHE_MASK;
-
         rcu_read_lock();
         hlist_for_each_entry_rcu(entry, pos, &cache->hashtable[nr], cr_hash) {
                 if (!entry->cr_ops->crmatch(acred, entry, flags))
@@ -378,30 +375,38 @@ rpcauth_init_cred(struct rpc_cred *cred, const struct auth_cred *acred,
 }
 EXPORT_SYMBOL_GPL(rpcauth_init_cred);
 
-struct rpc_cred *
-rpcauth_bindcred(struct rpc_task *task)
+void
+rpcauth_bind_root_cred(struct rpc_task *task)
 {
         struct rpc_auth *auth = task->tk_client->cl_auth;
         struct auth_cred acred = {
-                .uid = current->fsuid,
-                .gid = current->fsgid,
-                .group_info = current->group_info,
+                .uid = 0,
+                .gid = 0,
         };
         struct rpc_cred *ret;
-        int flags = 0;
 
         dprintk("RPC: %5u looking up %s cred\n",
                 task->tk_pid, task->tk_client->cl_auth->au_ops->au_name);
-        get_group_info(acred.group_info);
-        if (task->tk_flags & RPC_TASK_ROOTCREDS)
-                flags |= RPCAUTH_LOOKUP_ROOTCREDS;
-        ret = auth->au_ops->lookup_cred(auth, &acred, flags);
+        ret = auth->au_ops->lookup_cred(auth, &acred, 0);
+        if (!IS_ERR(ret))
+                task->tk_msg.rpc_cred = ret;
+        else
+                task->tk_status = PTR_ERR(ret);
+}
+
+void
+rpcauth_bindcred(struct rpc_task *task)
+{
+        struct rpc_auth *auth = task->tk_client->cl_auth;
+        struct rpc_cred *ret;
+
+        dprintk("RPC: %5u looking up %s cred\n",
+                task->tk_pid, auth->au_ops->au_name);
+        ret = rpcauth_lookupcred(auth, 0);
         if (!IS_ERR(ret))
                 task->tk_msg.rpc_cred = ret;
         else
                 task->tk_status = PTR_ERR(ret);
-        put_group_info(acred.group_info);
-        return ret;
 }
 
 void
diff --git a/net/sunrpc/auth_unix.c b/net/sunrpc/auth_unix.c
index 5ed91e5bcee4..b763710d3dbd 100644
--- a/net/sunrpc/auth_unix.c
+++ b/net/sunrpc/auth_unix.c
@@ -60,7 +60,8 @@ static struct rpc_cred *
 unx_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
 {
         struct unx_cred *cred;
-        int             i;
+        unsigned int groups = 0;
+        unsigned int i;
 
         dprintk("RPC:       allocating UNIX cred for uid %d gid %d\n",
                         acred->uid, acred->gid);
@@ -70,21 +71,17 @@ unx_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
 
         rpcauth_init_cred(&cred->uc_base, acred, auth, &unix_credops);
         cred->uc_base.cr_flags = 1UL << RPCAUTH_CRED_UPTODATE;
-        if (flags & RPCAUTH_LOOKUP_ROOTCREDS) {
-                cred->uc_uid = 0;
-                cred->uc_gid = 0;
-                cred->uc_gids[0] = NOGROUP;
-        } else {
-                int groups = acred->group_info->ngroups;
-                if (groups > NFS_NGROUPS)
-                        groups = NFS_NGROUPS;
-
-                cred->uc_gid = acred->gid;
-                for (i = 0; i < groups; i++)
-                        cred->uc_gids[i] = GROUP_AT(acred->group_info, i);
-                if (i < NFS_NGROUPS)
-                  cred->uc_gids[i] = NOGROUP;
-        }
+
+        if (acred->group_info != NULL)
+                groups = acred->group_info->ngroups;
+        if (groups > NFS_NGROUPS)
+                groups = NFS_NGROUPS;
+
+        cred->uc_gid = acred->gid;
+        for (i = 0; i < groups; i++)
+                cred->uc_gids[i] = GROUP_AT(acred->group_info, i);
+        if (i < NFS_NGROUPS)
+                cred->uc_gids[i] = NOGROUP;
 
         return &cred->uc_base;
 }
@@ -118,26 +115,21 @@ static int
 unx_match(struct auth_cred *acred, struct rpc_cred *rcred, int flags)
 {
         struct unx_cred *cred = container_of(rcred, struct unx_cred, uc_base);
-        int             i;
+        unsigned int groups = 0;
+        unsigned int i;
 
-        if (!(flags & RPCAUTH_LOOKUP_ROOTCREDS)) {
-                int groups;
 
-                if (cred->uc_uid != acred->uid
-                 || cred->uc_gid != acred->gid)
-                        return 0;
+        if (cred->uc_uid != acred->uid || cred->uc_gid != acred->gid)
+                return 0;
 
+        if (acred->group_info != NULL)
                 groups = acred->group_info->ngroups;
-                if (groups > NFS_NGROUPS)
-                        groups = NFS_NGROUPS;
-                for (i = 0; i < groups ; i++)
-                        if (cred->uc_gids[i] != GROUP_AT(acred->group_info, i))
-                                return 0;
-                return 1;
-        }
-        return (cred->uc_uid == 0
-             && cred->uc_gid == 0
-             && cred->uc_gids[0] == (gid_t) NOGROUP);
+        if (groups > NFS_NGROUPS)
+                groups = NFS_NGROUPS;
+        for (i = 0; i < groups ; i++)
+                if (cred->uc_gids[i] != GROUP_AT(acred->group_info, i))
+                        return 0;
+        return 1;
 }
 
 /*
diff --git a/net/sunrpc/sched.c b/net/sunrpc/sched.c
index cae219c8caeb..7db956f6e018 100644
--- a/net/sunrpc/sched.c
+++ b/net/sunrpc/sched.c
@@ -821,8 +821,10 @@ static void rpc_init_task(struct rpc_task *task, const struct rpc_task_setup *ta
                 /* Bind the user cred */
                 if (task->tk_msg.rpc_cred != NULL)
                         rpcauth_holdcred(task);
-                else
+                else if (!(task_setup_data->flags & RPC_TASK_ROOTCREDS))
                         rpcauth_bindcred(task);
+                else
+                        rpcauth_bind_root_cred(task);
                 if (task->tk_action == NULL)
                         rpc_call_start(task);
         }