SUNRPC: Fix read ordering problems with req->rq_private_buf.len

[mv-sheeva.git] / net / sunrpc / clnt.c

diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index fe95bd0ab1e96a40bdf0dc0be5e520ddd33b1ab3..3ae5604645135ec665c7415c77f1b043281df89f 100644 (file)
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -548,7 +548,7 @@ EXPORT_SYMBOL_GPL(rpc_run_task);
  * @msg: RPC call parameters
  * @flags: RPC call flags
  */
-int rpc_call_sync(struct rpc_clnt *clnt, struct rpc_message *msg, int flags)
+int rpc_call_sync(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags)
 {
        struct rpc_task *task;
        struct rpc_task_setup task_setup_data = {
@@ -579,7 +579,7 @@ EXPORT_SYMBOL_GPL(rpc_call_sync);
  * @data: user call data
  */
 int
-rpc_call_async(struct rpc_clnt *clnt, struct rpc_message *msg, int flags,
+rpc_call_async(struct rpc_clnt *clnt, const struct rpc_message *msg, int flags,
               const struct rpc_call_ops *tk_ops, void *data)
 {
        struct rpc_task *task;
@@ -1066,7 +1066,7 @@ call_transmit(struct rpc_task *task)
        if (task->tk_msg.rpc_proc->p_decode != NULL)
                return;
        task->tk_action = rpc_exit_task;
-       rpc_wake_up_task(task);
+       rpc_wake_up_queued_task(&task->tk_xprt->pending, task);
 }
 
 /*
@@ -1199,18 +1199,6 @@ call_decode(struct rpc_task *task)
                task->tk_flags &= ~RPC_CALL_MAJORSEEN;
        }
 
-       if (task->tk_status < 12) {
-               if (!RPC_IS_SOFT(task)) {
-                       task->tk_action = call_bind;
-                       clnt->cl_stats->rpcretrans++;
-                       goto out_retry;
-               }
-               dprintk("RPC:       %s: too small RPC reply size (%d bytes)\n",
-                               clnt->cl_protname, task->tk_status);
-               task->tk_action = call_timeout;
-               goto out_retry;
-       }
-
        /*
         * Ensure that we see all writes made by xprt_complete_rqst()
         * before it changed req->rq_received.
@@ -1222,6 +1210,18 @@ call_decode(struct rpc_task *task)
        WARN_ON(memcmp(&req->rq_rcv_buf, &req->rq_private_buf,
                                sizeof(req->rq_rcv_buf)) != 0);
 
+       if (req->rq_rcv_buf.len < 12) {
+               if (!RPC_IS_SOFT(task)) {
+                       task->tk_action = call_bind;
+                       clnt->cl_stats->rpcretrans++;
+                       goto out_retry;
+               }
+               dprintk("RPC:       %s: too small RPC reply size (%d bytes)\n",
+                               clnt->cl_protname, task->tk_status);
+               task->tk_action = call_timeout;
+               goto out_retry;
+       }
+
        /* Verify the RPC header */
        p = call_verify(task);
        if (IS_ERR(p)) {
@@ -1240,10 +1240,13 @@ call_decode(struct rpc_task *task)
                        task->tk_status);
        return;
 out_retry:
-       req->rq_received = req->rq_private_buf.len = 0;
        task->tk_status = 0;
-       if (task->tk_client->cl_discrtry)
-               xprt_force_disconnect(task->tk_xprt);
+       /* Note: call_verify() may have freed the RPC slot */
+       if (task->tk_rqstp == req) {
+               req->rq_received = req->rq_rcv_buf.len = 0;
+               if (task->tk_client->cl_discrtry)
+                       xprt_force_disconnect(task->tk_xprt);
+       }
 }
 
 /*