Re: [PATCH v2] net/mlx5e: fix bpf_prog reference count leaks in mlx5e_alloc_rq

[Saeed Mahameed]

On Thu, 2020-07-30 at 18:29 +0800, Xin Xiong wrote:
> 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")
> 

Please don't break the line of the fixes tag.
I will fix this up.

> Signed-off-by: Xin Xiong 
> Signed-off-by: Xiyu Yang 
> Signed-off-by: Xin Tan 
> ---
> v1 -> v2:
> - Amended parts of wording to be better understood
> - Added Fixes tag
> ---

Applied to net-mlx5, Thanks !

Re: [PATCH v2] net/mlx5e: fix bpf_prog reference count leaks in mlx5e_alloc_rq

[Jakub Kicinski]

On Thu, 30 Jul 2020 18:29:41 +0800 Xin Xiong wrote:
> Fixes: 422d4c401edd ("net/mlx5e: RX, Split WQ objects for different RQ
> types")
> 
> Signed-off-by: Xin Xiong 
> Signed-off-by: Xiyu Yang 
> Signed-off-by: Xin Tan 

Thanks for the patch, please make sure Fixes tag is not line-wrapped
and there is no empty line between that and the sign-offs.

[PATCH v2] net/mlx5e: fix bpf_prog reference count leaks in mlx5e_alloc_rq

[Xin Xiong]

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 
Signed-off-by: Xiyu Yang 
Signed-off-by: Xin Tan 
---
v1 -> v2:
- Amended parts of wording to be better understood
- Added Fixes tag
---
 drivers/net/ethernet/mellanox/mlx5/core/en_main.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c 
b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index a836a02a2116..8e1b1ab416d8 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -419,7 +419,7 @@ static int mlx5e_alloc_rq(struct mlx5e_channel *c,
err = mlx5_wq_ll_create(mdev, >wq, rqc_wq, >mpwqe.wq,
>wq_ctrl);
if (err)
-   return err;
+   goto err_rq_wq_destroy;
 
rq->mpwqe.wq.db = >mpwqe.wq.db[MLX5_RCV_DBR];
 
@@ -470,7 +470,7 @@ static int mlx5e_alloc_rq(struct mlx5e_channel *c,
err = mlx5_wq_cyc_create(mdev, >wq, rqc_wq, >wqe.wq,
 >wq_ctrl);
if (err)
-   return err;
+   goto err_rq_wq_destroy;
 
rq->wqe.wq.db = >wqe.wq.db[MLX5_RCV_DBR];
 
-- 
2.25.1