[PATCH for-next] RDMA/core: Fix ib_qp_usecnt_dec() called when error

[PATCH for-next] RDMA/core: Fix ib_qp_usecnt_dec() called when error

[Yajun Deng]

ib_destroy_qp() would called by ib_create_qp_user() if error, the former
contains ib_qp_usecnt_dec(), but ib_qp_usecnt_inc() was not called before.

So move ib_qp_usecnt_inc() into create_qp().

Fixes: d2b10794fc13 ("RDMA/core: Create clean QP creations interface for uverbs")
Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
---
 drivers/infiniband/core/uverbs_cmd.c          | 1 -
 drivers/infiniband/core/uverbs_std_types_qp.c | 1 -
 drivers/infiniband/core/verbs.c               | 3 +--
 3 files changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c
index 6b6393176b3c..4437f834c0a7 100644
--- a/drivers/infiniband/core/uverbs_cmd.c
+++ b/drivers/infiniband/core/uverbs_cmd.c
@@ -1437,7 +1437,6 @@ static int create_qp(struct uverbs_attr_bundle *attrs,
 		ret = PTR_ERR(qp);
 		goto err_put;
 	}
-	ib_qp_usecnt_inc(qp);
 
 	obj->uevent.uobject.object = qp;
 	obj->uevent.event_file = READ_ONCE(attrs->ufile->default_async_file);
diff --git a/drivers/infiniband/core/uverbs_std_types_qp.c b/drivers/infiniband/core/uverbs_std_types_qp.c
index dd1075466f61..75353e09c6fe 100644
--- a/drivers/infiniband/core/uverbs_std_types_qp.c
+++ b/drivers/infiniband/core/uverbs_std_types_qp.c
@@ -254,7 +254,6 @@ static int UVERBS_HANDLER(UVERBS_METHOD_QP_CREATE)(
 		ret = PTR_ERR(qp);
 		goto err_put;
 	}
-	ib_qp_usecnt_inc(qp);
 
 	if (attr.qp_type == IB_QPT_XRC_TGT) {
 		obj->uxrcd = container_of(xrcd_uobj, struct ib_uxrcd_object,
diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c
index a9819c40a140..bc9a83f1ca2d 100644
--- a/drivers/infiniband/core/verbs.c
+++ b/drivers/infiniband/core/verbs.c
@@ -1245,6 +1245,7 @@ static struct ib_qp *create_qp(struct ib_device *dev, struct ib_pd *pd,
 	if (ret)
 		goto err_security;
 
+	ib_qp_usecnt_inc(qp);
 	rdma_restrack_add(&qp->res);
 	return qp;
 
@@ -1345,8 +1346,6 @@ struct ib_qp *ib_create_qp_kernel(struct ib_pd *pd,
 	if (IS_ERR(qp))
 		return qp;
 
-	ib_qp_usecnt_inc(qp);
-
 	if (qp_init_attr->cap.max_rdma_ctxs) {
 		ret = rdma_rw_init_mrs(qp, qp_init_attr);
 		if (ret)
-- 
2.25.1

Re: [PATCH for-next] RDMA/core: Fix ib_qp_usecnt_dec() called when error

[Leon Romanovsky]

On Thu, Mar 03, 2022 at 10:42:32AM +0800, Yajun Deng wrote:
> ib_destroy_qp() would called by ib_create_qp_user() if error, the former
> contains ib_qp_usecnt_dec(), but ib_qp_usecnt_inc() was not called before.
> 
> So move ib_qp_usecnt_inc() into create_qp().
> 
> Fixes: d2b10794fc13 ("RDMA/core: Create clean QP creations interface for uverbs")
> Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
> ---
>  drivers/infiniband/core/uverbs_cmd.c          | 1 -
>  drivers/infiniband/core/uverbs_std_types_qp.c | 1 -
>  drivers/infiniband/core/verbs.c               | 3 +--
>  3 files changed, 1 insertion(+), 4 deletions(-)
> 

Thanks,
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>

Re: [PATCH for-next] RDMA/core: Fix ib_qp_usecnt_dec() called when error

[Jason Gunthorpe]

On Thu, Mar 03, 2022 at 10:42:32AM +0800, Yajun Deng wrote:
> ib_destroy_qp() would called by ib_create_qp_user() if error, the former
> contains ib_qp_usecnt_dec(), but ib_qp_usecnt_inc() was not called before.
> 
> So move ib_qp_usecnt_inc() into create_qp().
> 
> Fixes: d2b10794fc13 ("RDMA/core: Create clean QP creations interface for uverbs")
> Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
> Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
> ---
>  drivers/infiniband/core/uverbs_cmd.c          | 1 -
>  drivers/infiniband/core/uverbs_std_types_qp.c | 1 -
>  drivers/infiniband/core/verbs.c               | 3 +--
>  3 files changed, 1 insertion(+), 4 deletions(-)

Applied to for-next, thanks

Jason