[PATCH 4.19 37/43] net/mlx5e: Fix two double free cases

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

From: Dinghao Liu <dinghao.liu@zju.edu.cn>

commit 7a6eb072a9548492ead086f3e820e9aac71c7138 upstream.

mlx5e_create_ttc_table_groups() frees ft->g on failure of
kvzalloc(), but such failure will be caught by its caller
in mlx5e_create_ttc_table() and ft->g will be freed again
in mlx5e_destroy_flow_table(). The same issue also occurs
in mlx5e_create_ttc_table_groups(). Set ft->g to NULL after
kfree() to avoid double free.

Fixes: 7b3722fa9ef6 ("net/mlx5e: Support RSS for GRE tunneled packets")
Fixes: 33cfaaa8f36f ("net/mlx5e: Split the main flow steering table")
Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/net/ethernet/mellanox/mlx5/core/en_fs.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/net/ethernet/mellanox/mlx5/core/en_fs.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_fs.c
@@ -893,6 +893,7 @@ static int mlx5e_create_ttc_table_groups
 	in = kvzalloc(inlen, GFP_KERNEL);
 	if (!in) {
 		kfree(ft->g);
+		ft->g = NULL;
 		return -ENOMEM;
 	}
 
@@ -1033,6 +1034,7 @@ static int mlx5e_create_inner_ttc_table_
 	in = kvzalloc(inlen, GFP_KERNEL);
 	if (!in) {
 		kfree(ft->g);
+		ft->g = NULL;
 		return -ENOMEM;
 	}