4.17-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 @@ -271,7 +271,7 @@ 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; if (priv->hdr_type == HFI1_PKT_TYPE_9B) { --- 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. @@ -482,7 +482,7 @@ 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;