From 64d26422516b2e347b32e6d9b1d40b3c19a62aae Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Tue, 30 Jun 2020 15:55:45 -0400 Subject: [PATCH] svcrdma: Fix another Receive buffer leak During a connection tear down, the Receive queue is flushed before the device resources are freed. Typically, all the Receives flush with IB_WR_FLUSH_ERR. However, any pending successful Receives flush with IB_WR_SUCCESS, and the server automatically posts a fresh Receive to replace the completing one. This happens even after the connection has closed and the RQ is drained. Receives that are posted after the RQ is drained appear never to complete, causing a Receive resource leak. The leaked Receive buffer is left DMA-mapped. To prevent these late-posted recv_ctxt's from leaking, block new Receive posting after XPT_CLOSE is set. Signed-off-by: Chuck Lever --- net/sunrpc/xprtrdma/svc_rdma_recvfrom.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c index d5ec85cb652c..5bb97b5f4606 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c +++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c @@ -275,6 +275,8 @@ static int svc_rdma_post_recv(struct svcxprt_rdma *rdma) { struct svc_rdma_recv_ctxt *ctxt; + if (test_bit(XPT_CLOSE, &rdma->sc_xprt.xpt_flags)) + return 0; ctxt = svc_rdma_recv_ctxt_get(rdma); if (!ctxt) return -ENOMEM;