From: Xin Xiong <xiongx18@fudan.edu.cn>
Date: Thu, 30 Jul 2020 18:29:41 +0800
Subject: net/mlx5e: fix bpf_prog reference count leaks in mlx5e_alloc_rq
Patch-mainline: v5.8
Git-commit: e692139e6af339a1495ef401b2d95f7f9d1c7a44
References: bsc#1103990 FATE#326006

The function invokes bpf_prog_inc(), which increases the reference
count of a bpf_prog object "rq->xdp_prog" if the object isn't NULL.

The refcount leak issues take place in two error handling paths. When
either mlx5_wq_ll_create() or mlx5_wq_cyc_create() fails, the function
simply returns the error code and forgets to drop the reference count
increased earlier, causing a reference count leak of "rq->xdp_prog".

Fix this issue by jumping to the error handling path err_rq_wq_destroy
while either function fails.

Fixes: 422d4c401edd ("net/mlx5e: RX, Split WQ objects for different RQ types")
Signed-off-by: Xin Xiong <xiongx18@fudan.edu.cn>
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/mellanox/mlx5/core/en_main.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -529,7 +529,7 @@ static int mlx5e_alloc_rq(struct mlx5e_c
 		err = mlx5_wq_ll_create(mdev, &rqp->wq, rqc_wq, &rq->mpwqe.wq,
 					&rq->wq_ctrl);
 		if (err)
-			return err;
+			goto err_rq_wq_destroy;
 
 		rq->mpwqe.wq.db = &rq->mpwqe.wq.db[MLX5_RCV_DBR];
 
@@ -574,7 +574,7 @@ static int mlx5e_alloc_rq(struct mlx5e_c
 		err = mlx5_wq_cyc_create(mdev, &rqp->wq, rqc_wq, &rq->wqe.wq,
 					 &rq->wq_ctrl);
 		if (err)
-			return err;
+			goto err_rq_wq_destroy;
 
 		rq->wqe.wq.db = &rq->wqe.wq.db[MLX5_RCV_DBR];