Re: [PATCH net-next] net/mlx5: check for allocation failure in mlx5_ft_pool_init()

On Thu, Jun 03, 2021 at 04:12:38PM +0300, Leon Romanovsky wrote:

On Thu, Jun 03, 2021 at 03:39:24PM +0300, Dan Carpenter wrote:

quoted

Add a check for if the kzalloc() fails.

Fixes: 4a98544d1827 ("net/mlx5: Move chains ft pool to be used by all firmware steering")
Signed-off-by: Dan Carpenter <redacted>
---
 drivers/net/ethernet/mellanox/mlx5/core/fs_ft_pool.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/fs_ft_pool.c b/drivers/net/ethernet/mellanox/mlx5/core/fs_ft_pool.c
index 526fbb669142..c14590acc772 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/fs_ft_pool.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/fs_ft_pool.c

@@ -27,6 +27,8 @@ int mlx5_ft_pool_init(struct mlx5_core_dev *dev)
 	int i;
 
 	ft_pool = kzalloc(sizeof(*ft_pool), GFP_KERNEL);
+	if (!ft_pool)
+		return -ENOMEM;
 
 	for (i = ARRAY_SIZE(FT_POOLS) - 1; i >= 0; i--)
 		ft_pool->ft_left[i] = FT_SIZE / FT_POOLS[i];

Dan thanks for your patch.

When reviewed your patch, I spotted another error in the patch from the Fixes line.

  2955         err = mlx5_ft_pool_init(dev);
  2956         if (err)
  2957                 return err;
  2958
  2959         steering = kzalloc(sizeof(*steering), GFP_KERNEL);
  2960         if (!steering)
  2961                 goto err;
                       ^^^^^^^^ it will return success, while should return ENOMEM.

Smatch prints a static checker warning for this, but I never finished
going through the backlog of old "missing error code" warnings.  At one
point I was down to 38 warnings left but now I see that the backlog is
62 warnings so people are adding new bugs faster than I'm reviewing
them...  :P

I will take care of this tomorrow as a separate patch.  I will just
report or the other 61 warnings and get the backlog cleared out so that
I can start checking these better in the future.

regards,
dan carpenter