Patch "RDMA/rxe: Fix coding error in rxe_recv.c" has been added to the 5.11-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    RDMA/rxe: Fix coding error in rxe_recv.c

to the 5.11-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     rdma-rxe-fix-coding-error-in-rxe_recv.c.patch
and it can be found in the queue-5.11 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 0029fdf723a99b6abaafd14355d0575cf10f88ca
Author: Bob Pearson <rpearsonhpe@xxxxxxxxx>
Date:   Wed Jan 27 15:45:01 2021 -0600

    RDMA/rxe: Fix coding error in rxe_recv.c
    
    [ 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>

diff --git a/drivers/infiniband/sw/rxe/rxe_recv.c b/drivers/infiniband/sw/rxe/rxe_recv.c
index c9984a28eecc7..db0ee5c3962e4 100644
--- a/drivers/infiniband/sw/rxe/rxe_recv.c
+++ b/drivers/infiniband/sw/rxe/rxe_recv.c
@@ -9,21 +9,26 @@
 #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;
 		}
@@ -31,7 +36,7 @@ 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;
 		}