RDMA: Check umem pointer validity prior to release

Update ib_umem_release() to behave similarly to kfree() and allow
submitting NULL pointer as safe input to this function.

Fixes: a52c8e2469 ("RDMA: Clean destroy CQ in drivers do not return errors")
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/hns/hns_roce_cq.c

@@ -423,9 +423,8 @@ err_dbmap:
 
 err_mtt:
 	hns_roce_mtt_cleanup(hr_dev, &hr_cq->hr_buf.hr_mtt);
-	if (udata)
-		ib_umem_release(hr_cq->umem);
-	else
+	ib_umem_release(hr_cq->umem);
+	if (!udata)
 		hns_roce_ib_free_cq_buf(hr_dev, &hr_cq->hr_buf,
 					hr_cq->ib_cq.cqe);
 
@@ -451,9 +450,8 @@ void hns_roce_ib_destroy_cq(struct ib_cq *ib_cq, struct ib_udata *udata)
 	hns_roce_free_cq(hr_dev, hr_cq);
 	hns_roce_mtt_cleanup(hr_dev, &hr_cq->hr_buf.hr_mtt);
 
+	ib_umem_release(hr_cq->umem);
 	if (udata) {
-		ib_umem_release(hr_cq->umem);
-
 		if (hr_cq->db_en == 1)
 			hns_roce_db_unmap_user(rdma_udata_to_drv_context(
 						       udata,

drivers/infiniband/hw/hns/hns_roce_hw_v1.c

@@ -1163,8 +1163,7 @@ free_mr:
 	hns_roce_bitmap_free(&hr_dev->mr_table.mtpt_bitmap,
 			     key_to_hw_index(mr->key), 0);
 
-	if (mr->umem)
-		ib_umem_release(mr->umem);
+	ib_umem_release(mr->umem);
 
 	kfree(mr);
 
@@ -3641,9 +3640,8 @@ int hns_roce_v1_destroy_qp(struct ib_qp *ibqp, struct ib_udata *udata)
 
 	hns_roce_mtt_cleanup(hr_dev, &hr_qp->mtt);
 
-	if (udata)
-		ib_umem_release(hr_qp->umem);
-	else {
+	ib_umem_release(hr_qp->umem);
+	if (!udata) {
 		kfree(hr_qp->sq.wrid);
 		kfree(hr_qp->rq.wrid);
 
@@ -3694,9 +3692,8 @@ static void hns_roce_v1_destroy_cq(struct ib_cq *ibcq, struct ib_udata *udata)
 
 	hns_roce_mtt_cleanup(hr_dev, &hr_cq->hr_buf.hr_mtt);
 
-	if (ibcq->uobject)
-		ib_umem_release(hr_cq->umem);
-	else {
+	ib_umem_release(hr_cq->umem);
+	if (!udata) {
 		/* Free the buff of stored cq */
 		cq_buf_size = (ibcq->cqe + 1) * hr_dev->caps.cq_entry_sz;
 		hns_roce_buf_free(hr_dev, cq_buf_size, &hr_cq->hr_buf.hr_buf);

drivers/infiniband/hw/hns/hns_roce_hw_v2.c

@@ -4582,7 +4582,6 @@ static int hns_roce_v2_destroy_qp_common(struct hns_roce_dev *hr_dev,
 
 		if (hr_qp->rq.wqe_cnt && (hr_qp->rdb_en == 1))
 			hns_roce_db_unmap_user(context, &hr_qp->rdb);
-		ib_umem_release(hr_qp->umem);
 	} else {
 		kfree(hr_qp->sq.wrid);
 		kfree(hr_qp->rq.wrid);
@@ -4590,6 +4589,7 @@ static int hns_roce_v2_destroy_qp_common(struct hns_roce_dev *hr_dev,
 		if (hr_qp->rq.wqe_cnt)
 			hns_roce_free_db(hr_dev, &hr_qp->rdb);
 	}
+	ib_umem_release(hr_qp->umem);
 
 	if ((hr_dev->caps.flags & HNS_ROCE_CAP_FLAG_RQ_INLINE) &&
 	     hr_qp->rq.wqe_cnt) {

drivers/infiniband/hw/hns/hns_roce_mr.c

@@ -1298,9 +1298,7 @@ int hns_roce_dereg_mr(struct ib_mr *ibmr, struct ib_udata *udata)
 	} else {
 		hns_roce_mr_free(hr_dev, mr);
 
-		if (mr->umem)
-			ib_umem_release(mr->umem);
-
+		ib_umem_release(mr->umem);
 		kfree(mr);
 	}
 

drivers/infiniband/hw/hns/hns_roce_qp.c

@@ -938,10 +938,9 @@ err_get_bufs:
 	hns_roce_free_buf_list(buf_list, hr_qp->region_cnt);
 
 err_alloc_list:
-	if (hr_qp->umem)
-		ib_umem_release(hr_qp->umem);
-	else
+	if (!hr_qp->umem)
 		hns_roce_buf_free(hr_dev, hr_qp->buff_size, &hr_qp->hr_buf);
+	ib_umem_release(hr_qp->umem);
 
 err_db:
 	if (!udata && hns_roce_qp_has_rq(init_attr) &&

drivers/infiniband/hw/hns/hns_roce_srq.c

@@ -380,8 +380,7 @@ err_idx_buf:
 	hns_roce_mtt_cleanup(hr_dev, &srq->idx_que.mtt);
 
 err_idx_mtt:
-	if (udata)
-		ib_umem_release(srq->idx_que.umem);
+	ib_umem_release(srq->idx_que.umem);
 
 err_create_idx:
 	hns_roce_buf_free(hr_dev, srq->idx_que.buf_size,
@@ -392,9 +391,8 @@ err_srq_mtt:
 	hns_roce_mtt_cleanup(hr_dev, &srq->mtt);
 
 err_buf:
-	if (udata)
-		ib_umem_release(srq->umem);
-	else
+	ib_umem_release(srq->umem);
+	if (!udata)
 		hns_roce_buf_free(hr_dev, srq_buf_size, &srq->buf);
 
 	return ret;
@@ -408,15 +406,15 @@ void hns_roce_destroy_srq(struct ib_srq *ibsrq, struct ib_udata *udata)
 	hns_roce_srq_free(hr_dev, srq);
 	hns_roce_mtt_cleanup(hr_dev, &srq->mtt);
 
-	if (ibsrq->uobject) {
+	if (udata) {
 		hns_roce_mtt_cleanup(hr_dev, &srq->idx_que.mtt);
-		ib_umem_release(srq->idx_que.umem);
-		ib_umem_release(srq->umem);
 	} else {
 		kvfree(srq->wrid);
 		hns_roce_buf_free(hr_dev, srq->max << srq->wqe_shift,
 				  &srq->buf);
 	}
+	ib_umem_release(srq->idx_que.umem);
+	ib_umem_release(srq->umem);
 }
 
 int hns_roce_init_srq_table(struct hns_roce_dev *hr_dev)