RPC: Ensure that we disconnect TCP socket when client requests error out

If we're part way through transmitting a TCP request, and the client
errors, then we need to disconnect and reconnect the TCP socket in order to
avoid confusing the server.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
(cherry picked from 031a50c8b9ea82616abd4a4e18021a25848941ce commit)

1 files changed, 28 insertions, 1 deletions

diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index ee678ed13b6f..441bd53f5eca 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -414,6 +414,33 @@ static int xs_tcp_send_request(struct rpc_task *task)
 }
 
 /**
+ * xs_tcp_release_xprt - clean up after a tcp transmission
+ * @xprt: transport
+ * @task: rpc task
+ *
+ * This cleans up if an error causes us to abort the transmission of a request.
+ * In this case, the socket may need to be reset in order to avoid confusing
+ * the server.
+ */
+static void xs_tcp_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task)
+{
+        struct rpc_rqst *req;
+
+        if (task != xprt->snd_task)
+                return;
+        if (task == NULL)
+                goto out_release;
+        req = task->tk_rqstp;
+        if (req->rq_bytes_sent == 0)
+                goto out_release;
+        if (req->rq_bytes_sent == req->rq_snd_buf.len)
+                goto out_release;
+        set_bit(XPRT_CLOSE_WAIT, &task->tk_xprt->state);
+out_release:
+        xprt_release_xprt(xprt, task);
+}
+
+/**
  * xs_close - close a socket
  * @xprt: transport
  *
@@ -1250,7 +1277,7 @@ static struct rpc_xprt_ops xs_udp_ops = {
 
 static struct rpc_xprt_ops xs_tcp_ops = {
         .reserve_xprt           = xprt_reserve_xprt,
-        .release_xprt           = xprt_release_xprt,
+        .release_xprt           = xs_tcp_release_xprt,
         .set_port               = xs_set_port,
         .connect                = xs_connect,
         .buf_alloc              = rpc_malloc,