[PATCH 4.20 012/171] IB/{hfi1, qib}: Fix WC.byte_len calculation for UD_SEND_WITH_IMM

[Greg Kroah-Hartman]

4.20-stable review patch.  If anyone has any objections, please let me know.

------------------

[ Upstream commit 904bba211acc2112fdf866e5a2bc6cd9ecd0de1b ]

The work completion length for a receiving a UD send with immediate is
short by 4 bytes causing application using this opcode to fail.

The UD receive logic incorrectly subtracts 4 bytes for immediate
value. These bytes are already included in header length and are used to
calculate header/payload split, so the result is these 4 bytes are
subtracted twice, once when the header length subtracted from the overall
length and once again in the UD opcode specific path.

Remove the extra subtraction when handling the opcode.

Fixes: 7724105686e7 ("IB/hfi1: add driver files")
Reviewed-by: Michael J. Ruhl <michael.j.ruhl@xxxxxxxxx>
Signed-off-by: Brian Welty <brian.welty@xxxxxxxxx>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@xxxxxxxxx>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@xxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/infiniband/hw/hfi1/ud.c    | 1 -
 drivers/infiniband/hw/qib/qib_ud.c | 1 -
 2 files changed, 2 deletions(-)

diff --git a/drivers/infiniband/hw/hfi1/ud.c b/drivers/infiniband/hw/hfi1/ud.c
index 4baa8f4d49de..46bf74375ea6 100644
--- a/drivers/infiniband/hw/hfi1/ud.c
+++ b/drivers/infiniband/hw/hfi1/ud.c
@@ -980,7 +980,6 @@ void hfi1_ud_rcv(struct hfi1_packet *packet)
 	    opcode == IB_OPCODE_UD_SEND_ONLY_WITH_IMMEDIATE) {
 		wc.ex.imm_data = packet->ohdr->u.ud.imm_data;
 		wc.wc_flags = IB_WC_WITH_IMM;
-		tlen -= sizeof(u32);
 	} else if (opcode == IB_OPCODE_UD_SEND_ONLY) {
 		wc.ex.imm_data = 0;
 		wc.wc_flags = 0;
diff --git a/drivers/infiniband/hw/qib/qib_ud.c b/drivers/infiniband/hw/qib/qib_ud.c
index 4d4c31ea4e2d..90268b838d4e 100644
--- a/drivers/infiniband/hw/qib/qib_ud.c
+++ b/drivers/infiniband/hw/qib/qib_ud.c
@@ -513,7 +513,6 @@ void qib_ud_rcv(struct qib_ibport *ibp, struct ib_header *hdr,
 	    opcode == IB_OPCODE_UD_SEND_ONLY_WITH_IMMEDIATE) {
 		wc.ex.imm_data = ohdr->u.ud.imm_data;
 		wc.wc_flags = IB_WC_WITH_IMM;
-		tlen -= sizeof(u32);
 	} else if (opcode == IB_OPCODE_UD_SEND_ONLY) {
 		wc.ex.imm_data = 0;
 		wc.wc_flags = 0;
-- 
2.19.1