[PATCH 5.4 179/340] RDMA/rxe: Fix coding error in rxe_recv.c

[Greg Kroah-Hartman]

From: Bob Pearson <rpearsonhpe@xxxxxxxxx>

[ Upstream commit 7d9ae80e31df57dd3253e1ec514f0000aa588a81 ]

check_type_state() in rxe_recv.c is written as if the type bits in the
packet opcode were a bit mask which is not correct. This patch corrects
this code to compare all 3 type bits to the required type.

Fixes: 8700e3e7c485 ("Soft RoCE driver")
Link: https://lore.kernel.org/r/20210127214500.3707-1-rpearson@xxxxxxx
Signed-off-by: Bob Pearson <rpearson@xxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/infiniband/sw/rxe/rxe_recv.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/infiniband/sw/rxe/rxe_recv.c b/drivers/infiniband/sw/rxe/rxe_recv.c
index 9bfb98056fc2a..2dc808988d949 100644
--- a/drivers/infiniband/sw/rxe/rxe_recv.c
+++ b/drivers/infiniband/sw/rxe/rxe_recv.c
@@ -36,21 +36,26 @@
 #include "rxe.h"
 #include "rxe_loc.h"
 
+/* check that QP matches packet opcode type and is in a valid state */
 static int check_type_state(struct rxe_dev *rxe, struct rxe_pkt_info *pkt,
 			    struct rxe_qp *qp)
 {
+	unsigned int pkt_type;
+
 	if (unlikely(!qp->valid))
 		goto err1;
 
+	pkt_type = pkt->opcode & 0xe0;
+
 	switch (qp_type(qp)) {
 	case IB_QPT_RC:
-		if (unlikely((pkt->opcode & IB_OPCODE_RC) != 0)) {
+		if (unlikely(pkt_type != IB_OPCODE_RC)) {
 			pr_warn_ratelimited("bad qp type\n");
 			goto err1;
 		}
 		break;
 	case IB_QPT_UC:
-		if (unlikely(!(pkt->opcode & IB_OPCODE_UC))) {
+		if (unlikely(pkt_type != IB_OPCODE_UC)) {
 			pr_warn_ratelimited("bad qp type\n");
 			goto err1;
 		}
@@ -58,7 +63,7 @@ static int check_type_state(struct rxe_dev *rxe, struct rxe_pkt_info *pkt,
 	case IB_QPT_UD:
 	case IB_QPT_SMI:
 	case IB_QPT_GSI:
-		if (unlikely(!(pkt->opcode & IB_OPCODE_UD))) {
+		if (unlikely(pkt_type != IB_OPCODE_UD)) {
 			pr_warn_ratelimited("bad qp type\n");
 			goto err1;
 		}
-- 
2.27.0