From: "Michael J. Ruhl" <michael.j.ruhl@intel.com>
Date: Fri, 28 Sep 2018 07:34:57 -0700
Subject: IB/hfi1: Error path MAD response size is incorrect
Patch-mainline: v4.20-rc1
Git-commit: 935c84ac649a147e1aad2c48ee5c5a1a9176b2d0
References: bsc#1114685 FATE#325854

If a MAD packet has incorrect header information, the logic uses the reply
path to report the error.  The reply path expects *resp_len to be set
prior to return.  Unfortunately, *resp_len is set to 0 for this path.
This causes an incorrect response packet.

Fix by ensuring that the *resp_len is defaulted to the incoming packet
size (wc->bytes_len - sizeof(GRH)).

Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/infiniband/hw/hfi1/mad.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/infiniband/hw/hfi1/mad.c
+++ b/drivers/infiniband/hw/hfi1/mad.c
@@ -1,5 +1,5 @@
 /*
- * Copyright(c) 2015-2017 Intel Corporation.
+ * Copyright(c) 2015-2018 Intel Corporation.
  *
  * This file is provided under a dual BSD/GPLv2 license.  When using or
  * redistributing this file, you may do so under either license.
@@ -4836,7 +4836,7 @@ static int hfi1_process_opa_mad(struct i
 	int ret;
 	int pkey_idx;
 	int local_mad = 0;
-	u32 resp_len = 0;
+	u32 resp_len = in_wc->byte_len - sizeof(*in_grh);
 	struct hfi1_ibport *ibp = to_iport(ibdev, port);
 
 	pkey_idx = hfi1_lookup_pkey_idx(ibp, LIM_MGMT_P_KEY);