[PATCH 5.4 213/475] RDMA/mlx5: Fix memory leak in error flow for subscribe event routine

[Greg Kroah-Hartman]

From: Yongzhi Liu <lyz_cs@xxxxxxxxxx>

[ Upstream commit 087f9c3f2309ed183f7e4b85ae57121d8663224d ]

In case the second xa_insert() fails, the obj_event is not released.  Fix
the error unwind flow to free that memory to avoid a memory leak.

Fixes: 759738537142 ("IB/mlx5: Enable subscription for device events over DEVX")
Link: https://lore.kernel.org/r/1647018361-18266-1-git-send-email-lyz_cs@xxxxxxxxxx
Signed-off-by: Yongzhi Liu <lyz_cs@xxxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/infiniband/hw/mlx5/devx.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/infiniband/hw/mlx5/devx.c b/drivers/infiniband/hw/mlx5/devx.c
index 664e0f374ac0..747f42855b7b 100644
--- a/drivers/infiniband/hw/mlx5/devx.c
+++ b/drivers/infiniband/hw/mlx5/devx.c
@@ -1844,8 +1844,10 @@ subscribe_event_xa_alloc(struct mlx5_devx_event_table *devx_event_table,
 				key_level2,
 				obj_event,
 				GFP_KERNEL);
-		if (err)
+		if (err) {
+			kfree(obj_event);
 			return err;
+		}
 		INIT_LIST_HEAD(&obj_event->obj_sub_list);
 	}
 
-- 
2.34.1