IB/hfi1: Add limit test for RC/UC send via loopback

Fix potential memory corruption and panic in loopback for IB_WR_SEND
variants.

The code blindly assumes the posted length will fit in the fetched rwqe,
which is not a valid assumption.

Fix by adding a limit test, and triggering the appropriate send completion
and putting the QP in an error state.  This mimics the handling for
non-loopback QPs.

Fixes: 15703461533a ("IB/{hfi1, qib, rdmavt}: Move ruc_loopback to rdmavt")
Cc: <stable@vger.kernel.org> #v4.20+
Reviewed-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

diff --git a/drivers/infiniband/sw/rdmavt/qp.c b/drivers/infiniband/sw/rdmavt/qp.c
index a1bd8cf..c6cc3e4 100644 (file)
--- a/drivers/infiniband/sw/rdmavt/qp.c
+++ b/drivers/infiniband/sw/rdmavt/qp.c
@@ -2910,6 +2910,8 @@ send:
                        goto op_err;
                if (!ret)
                        goto rnr_nak;
+               if (wqe->length > qp->r_len)
+                       goto inv_err;
                break;
 
        case IB_WR_RDMA_WRITE_WITH_IMM:
@@ -3078,7 +3080,10 @@ op_err:
        goto err;
 
 inv_err:
-       send_status = IB_WC_REM_INV_REQ_ERR;
+       send_status =
+               sqp->ibqp.qp_type == IB_QPT_RC ?
+                       IB_WC_REM_INV_REQ_ERR :
+                       IB_WC_SUCCESS;
        wc.status = IB_WC_LOC_QP_OP_ERR;
        goto err;