SUNRPC: Fix an infinite loop in call_refresh/call_refreshresult

If the rpcauth_refreshcred() call returns an error other than
EACCES, ENOMEM or ETIMEDOUT, we currently end up looping forever
between call_refresh and call_refreshresult.

The correct thing to do here is to exit on all errors except
EAGAIN and ETIMEDOUT, for which case we retry 3 times, then
return EACCES.

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

1 files changed, 15 insertions, 9 deletions

diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index 9dab9573be41..92ce94f5146b 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -989,20 +989,26 @@ call_refreshresult(struct rpc_task *task)
         dprint_status(task);
 
         task->tk_status = 0;
-        task->tk_action = call_allocate;
-        if (status >= 0 && rpcauth_uptodatecred(task))
-                return;
+        task->tk_action = call_refresh;
         switch (status) {
-        case -EACCES:
-                rpc_exit(task, -EACCES);
-                return;
-        case -ENOMEM:
-                rpc_exit(task, -ENOMEM);
+        case 0:
+                if (rpcauth_uptodatecred(task))
+                        task->tk_action = call_allocate;
                 return;
         case -ETIMEDOUT:
                 rpc_delay(task, 3*HZ);
+        case -EAGAIN:
+                status = -EACCES;
+                if (!task->tk_cred_retry)
+                        break;
+                task->tk_cred_retry--;
+                dprintk("RPC: %5u %s: retry refresh creds\n",
+                                task->tk_pid, __func__);
+                return;
         }
-        task->tk_action = call_refresh;
+        dprintk("RPC: %5u %s: refresh creds failed with error %d\n",
+                                task->tk_pid, __func__, status);
+        rpc_exit(task, status);
 }
 
 /*