RDMA/rxe: Use structs to describe the uABI instead of opencoding

Open coding pointer math is not acceptable for describing the uABI in
RDMA. Provide structs for all the cases.

The udata is casted to the struct as close to the verbs entry point
as possible for maximum clarity. Function signatures and so forth
are revised to allow for this.

Tested-by: Yuval Shaia <yuval.shaia@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

1 files changed, 43 insertions, 5 deletions

diff --git a/drivers/infiniband/sw/rxe/rxe_verbs.c b/drivers/infiniband/sw/rxe/rxe_verbs.c
index 34539c3242a8..ced79e49234b 100644
--- a/drivers/infiniband/sw/rxe/rxe_verbs.c
+++ b/drivers/infiniband/sw/rxe/rxe_verbs.c
@@ -407,6 +407,13 @@ static struct ib_srq *rxe_create_srq(struct ib_pd *ibpd,
 	struct rxe_pd *pd = to_rpd(ibpd);
 	struct rxe_srq *srq;
 	struct ib_ucontext *context = udata ? ibpd->uobject->context : NULL;
+	struct rxe_create_srq_resp __user *uresp = NULL;
+
+	if (udata) {
+		if (udata->outlen < sizeof(*uresp))
+			return ERR_PTR(-EINVAL);
+		uresp = udata->outbuf;
+	}
 
 	err = rxe_srq_chk_attr(rxe, NULL, &init->attr, IB_SRQ_INIT_MASK);
 	if (err)
@@ -422,7 +429,7 @@ static struct ib_srq *rxe_create_srq(struct ib_pd *ibpd,
 	rxe_add_ref(pd);
 	srq->pd = pd;
 
-	err = rxe_srq_from_init(rxe, srq, init, context, udata);
+	err = rxe_srq_from_init(rxe, srq, init, context, uresp);
 	if (err)
 		goto err2;
 
@@ -443,12 +450,22 @@ static int rxe_modify_srq(struct ib_srq *ibsrq, struct ib_srq_attr *attr,
 	int err;
 	struct rxe_srq *srq = to_rsrq(ibsrq);
 	struct rxe_dev *rxe = to_rdev(ibsrq->device);
+	struct rxe_modify_srq_cmd ucmd = {};
+
+	if (udata) {
+		if (udata->inlen < sizeof(ucmd))
+			return -EINVAL;
+
+		err = ib_copy_from_udata(&ucmd, udata, sizeof(ucmd));
+		if (err)
+			return err;
+	}
 
 	err = rxe_srq_chk_attr(rxe, srq, attr, mask);
 	if (err)
 		goto err1;
 
-	err = rxe_srq_from_attr(rxe, srq, attr, mask, udata);
+	err = rxe_srq_from_attr(rxe, srq, attr, mask, &ucmd);
 	if (err)
 		goto err1;
 
@@ -517,6 +534,13 @@ static struct ib_qp *rxe_create_qp(struct ib_pd *ibpd,
 	struct rxe_dev *rxe = to_rdev(ibpd->device);
 	struct rxe_pd *pd = to_rpd(ibpd);
 	struct rxe_qp *qp;
+	struct rxe_create_qp_resp __user *uresp = NULL;
+
+	if (udata) {
+		if (udata->outlen < sizeof(*uresp))
+			return ERR_PTR(-EINVAL);
+		uresp = udata->outbuf;
+	}
 
 	err = rxe_qp_chk_init(rxe, init);
 	if (err)
@@ -538,7 +562,7 @@ static struct ib_qp *rxe_create_qp(struct ib_pd *ibpd,
 
 	rxe_add_index(qp);
 
-	err = rxe_qp_from_init(rxe, qp, pd, init, udata, ibpd);
+	err = rxe_qp_from_init(rxe, qp, pd, init, uresp, ibpd);
 	if (err)
 		goto err3;
 
@@ -888,6 +912,13 @@ static struct ib_cq *rxe_create_cq(struct ib_device *dev,
 	int err;
 	struct rxe_dev *rxe = to_rdev(dev);
 	struct rxe_cq *cq;
+	struct rxe_create_cq_resp __user *uresp = NULL;
+
+	if (udata) {
+		if (udata->outlen < sizeof(*uresp))
+			return ERR_PTR(-EINVAL);
+		uresp = udata->outbuf;
+	}
 
 	if (attr->flags)
 		return ERR_PTR(-EINVAL);
@@ -903,7 +934,7 @@ static struct ib_cq *rxe_create_cq(struct ib_device *dev,
 	}
 
 	err = rxe_cq_from_init(rxe, cq, attr->cqe, attr->comp_vector,
-			       context, udata);
+			       context, uresp);
 	if (err)
 		goto err2;
 
@@ -930,12 +961,19 @@ static int rxe_resize_cq(struct ib_cq *ibcq, int cqe, struct ib_udata *udata)
 	int err;
 	struct rxe_cq *cq = to_rcq(ibcq);
 	struct rxe_dev *rxe = to_rdev(ibcq->device);
+	struct rxe_resize_cq_resp __user *uresp = NULL;
+
+	if (udata) {
+		if (udata->outlen < sizeof(*uresp))
+			return -EINVAL;
+		uresp = udata->outbuf;
+	}
 
 	err = rxe_cq_chk_attr(rxe, cq, cqe, 0);
 	if (err)
 		goto err1;
 
-	err = rxe_cq_resize_queue(cq, cqe, udata);
+	err = rxe_cq_resize_queue(cq, cqe, uresp);
 	if (err)
 		goto err1;