From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Wed, 22 Apr 2020 12:36:41 +0300
Subject: mlxsw: Fix some IS_ERR() vs NULL bugs
Git-commit: c391eb8366ae052d571bb2841f1ccb4d39f3ceb8
Patch-mainline: 5.7-rc3
References: networking-stable-20_04_27

The mlxsw_sp_acl_rulei_create() function is supposed to return an error
pointer from mlxsw_afa_block_create().  The problem is that these
functions both return NULL instead of error pointers.  Half the callers
expect NULL and half expect error pointers so it could lead to a NULL
dereference on failure.

This patch changes both of them to return error pointers and changes all
the callers which checked for NULL to check for IS_ERR() instead.

[js] no spectrum_acl and spectrum_mr_tcam in 4.12 yet.

Fixes: 4cda7d8d7098 ("mlxsw: core: Introduce flexible actions support")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/net/ethernet/mellanox/mlxsw/core_acl_flex_actions.c |    4 ++--
 drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c          |    2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/net/ethernet/mellanox/mlxsw/core_acl_flex_actions.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/core_acl_flex_actions.c
@@ -318,7 +318,7 @@ struct mlxsw_afa_block *mlxsw_afa_block_
 
 	block = kzalloc(sizeof(*block), GFP_KERNEL);
 	if (!block)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 	INIT_LIST_HEAD(&block->resource_list);
 	block->afa = mlxsw_afa;
 
@@ -331,7 +331,7 @@ struct mlxsw_afa_block *mlxsw_afa_block_
 	mlxsw_afa_set_destroy(block->first_set);
 err_first_set_create:
 	kfree(block);
-	return NULL;
+	return ERR_PTR(-ENOMEM);
 }
 EXPORT_SYMBOL(mlxsw_afa_block_create);
 
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c
@@ -278,7 +278,7 @@ mlxsw_sp_acl_rulei_create(struct mlxsw_s
 
 	rulei = kzalloc(sizeof(*rulei), GFP_KERNEL);
 	if (!rulei)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 	rulei->act_block = mlxsw_afa_block_create(acl->mlxsw_sp->afa);
 	if (IS_ERR(rulei->act_block)) {
 		err = PTR_ERR(rulei->act_block);