[PATCH 4.14 41/54] IB/hfi1: Fix incorrect mixing of ERR_PTR and NULL return values

From: Greg Kroah-Hartman
Date: Mon Jul 16 2018 - 03:41:24 EST


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

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

From: Michael J. Ruhl <michael.j.ruhl@xxxxxxxxx>

commit b697d7d8c741f27b728a878fc55852b06d0f6f5e upstream.

The __get_txreq() function can return a pointer, ERR_PTR(-EBUSY), or NULL.
All of the relevant call sites look for IS_ERR, so the NULL return would
lead to a NULL pointer exception.

Do not use the ERR_PTR mechanism for this function.

Update all call sites to handle the return value correctly.

Clean up error paths to reflect return value.

Fixes: 45842abbb292 ("staging/rdma/hfi1: move txreq header code")
Cc: <stable@xxxxxxxxxxxxxxx> # 4.9.x+
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@xxxxxxxxx>
Reviewed-by: Kamenee Arumugam <kamenee.arumugam@xxxxxxxxx>
Signed-off-by: Michael J. Ruhl <michael.j.ruhl@xxxxxxxxx>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@xxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/infiniband/hw/hfi1/rc.c | 2 +-
drivers/infiniband/hw/hfi1/uc.c | 4 ++--
drivers/infiniband/hw/hfi1/ud.c | 4 ++--
drivers/infiniband/hw/hfi1/verbs_txreq.c | 4 ++--
drivers/infiniband/hw/hfi1/verbs_txreq.h | 4 ++--
5 files changed, 9 insertions(+), 9 deletions(-)

--- a/drivers/infiniband/hw/hfi1/rc.c
+++ b/drivers/infiniband/hw/hfi1/rc.c
@@ -273,7 +273,7 @@ int hfi1_make_rc_req(struct rvt_qp *qp,

lockdep_assert_held(&qp->s_lock);
ps->s_txreq = get_txreq(ps->dev, qp);
- if (IS_ERR(ps->s_txreq))
+ if (!ps->s_txreq)
goto bail_no_tx;

ps->s_txreq->phdr.hdr.hdr_type = priv->hdr_type;
--- a/drivers/infiniband/hw/hfi1/uc.c
+++ b/drivers/infiniband/hw/hfi1/uc.c
@@ -1,5 +1,5 @@
/*
- * Copyright(c) 2015, 2016 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.
@@ -72,7 +72,7 @@ int hfi1_make_uc_req(struct rvt_qp *qp,
int middle = 0;

ps->s_txreq = get_txreq(ps->dev, qp);
- if (IS_ERR(ps->s_txreq))
+ if (!ps->s_txreq)
goto bail_no_tx;

if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_SEND_OK)) {
--- a/drivers/infiniband/hw/hfi1/ud.c
+++ b/drivers/infiniband/hw/hfi1/ud.c
@@ -1,5 +1,5 @@
/*
- * Copyright(c) 2015, 2016 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.
@@ -479,7 +479,7 @@ int hfi1_make_ud_req(struct rvt_qp *qp,
u32 lid;

ps->s_txreq = get_txreq(ps->dev, qp);
- if (IS_ERR(ps->s_txreq))
+ if (!ps->s_txreq)
goto bail_no_tx;

if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_NEXT_SEND_OK)) {
--- a/drivers/infiniband/hw/hfi1/verbs_txreq.c
+++ b/drivers/infiniband/hw/hfi1/verbs_txreq.c
@@ -1,5 +1,5 @@
/*
- * Copyright(c) 2016 - 2017 Intel Corporation.
+ * Copyright(c) 2016 - 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.
@@ -94,7 +94,7 @@ struct verbs_txreq *__get_txreq(struct h
struct rvt_qp *qp)
__must_hold(&qp->s_lock)
{
- struct verbs_txreq *tx = ERR_PTR(-EBUSY);
+ struct verbs_txreq *tx = NULL;

write_seqlock(&dev->txwait_lock);
if (ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK) {
--- a/drivers/infiniband/hw/hfi1/verbs_txreq.h
+++ b/drivers/infiniband/hw/hfi1/verbs_txreq.h
@@ -1,5 +1,5 @@
/*
- * Copyright(c) 2016 Intel Corporation.
+ * Copyright(c) 2016 - 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.
@@ -83,7 +83,7 @@ static inline struct verbs_txreq *get_tx
if (unlikely(!tx)) {
/* call slow path to get the lock */
tx = __get_txreq(dev, qp);
- if (IS_ERR(tx))
+ if (!tx)
return tx;
}
tx->qp = qp;