releases/6.4.16/rdma-rxe-fix-unsafe-drain-work-queue-code.patch

From 31ae0995a40a513008d8853b5a2a63794db62f46 Mon Sep 17 00:00:00 2001
From: Sasha Levin <sashal@kernel.org>
Date: Tue, 20 Jun 2023 08:55:21 -0500
Subject: RDMA/rxe: Fix unsafe drain work queue code

From: Bob Pearson <rpearsonhpe@gmail.com>

[ Upstream commit 5993b75d0bc71cd2b441d174b028fc36180f032c ]

If create_qp does not fully succeed it is possible for qp cleanup
code to attempt to drain the send or recv work queues before the
queues have been created causing a seg fault. This patch checks
to see if the queues exist before attempting to drain them.

Link: https://lore.kernel.org/r/20230620135519.9365-3-rpearsonhpe@gmail.com
Reported-by: syzbot+2da1965168e7dbcba136@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-rdma/00000000000012d89205fe7cfe00@google.com/raw
Fixes: 49dc9c1f0c7e ("RDMA/rxe: Cleanup reset state handling in rxe_resp.c")
Fixes: fbdeb828a21f ("RDMA/rxe: Cleanup error state handling in rxe_comp.c")
Signed-off-by: Bob Pearson <rpearsonhpe@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/infiniband/sw/rxe/rxe_comp.c | 4 ++++
 drivers/infiniband/sw/rxe/rxe_resp.c | 4 ++++
 2 files changed, 8 insertions(+)

diff --git a/drivers/infiniband/sw/rxe/rxe_comp.c b/drivers/infiniband/sw/rxe/rxe_comp.c
index f46c5a5fd0aea..44fece204abdd 100644
--- a/drivers/infiniband/sw/rxe/rxe_comp.c
+++ b/drivers/infiniband/sw/rxe/rxe_comp.c
@@ -597,6 +597,10 @@ static void flush_send_queue(struct rxe_qp *qp, bool notify)
 	struct rxe_queue *q = qp->sq.queue;
 	int err;
 
+	/* send queue never got created. nothing to do. */
+	if (!qp->sq.queue)
+		return;
+
 	while ((wqe = queue_head(q, q->type))) {
 		if (notify) {
 			err = flush_send_wqe(qp, wqe);
diff --git a/drivers/infiniband/sw/rxe/rxe_resp.c b/drivers/infiniband/sw/rxe/rxe_resp.c
index ee68306555b99..ed5af55237d9f 100644
--- a/drivers/infiniband/sw/rxe/rxe_resp.c
+++ b/drivers/infiniband/sw/rxe/rxe_resp.c
@@ -1452,6 +1452,10 @@ static void flush_recv_queue(struct rxe_qp *qp, bool notify)
 	if (qp->srq)
 		return;
 
+	/* recv queue not created. nothing to do. */
+	if (!qp->rq.queue)
+		return;
+
 	while ((wqe = queue_head(q, q->type))) {
 		if (notify) {
 			err = flush_recv_wqe(qp, wqe);
-- 
2.40.1