net: prestera: acl: Add check for kmemdup

As the kemdup could return NULL, it should be better to check the return
value and return error if fails.
Moreover, the return value of prestera_acl_ruleset_keymask_set() should
be checked by cascade.

Fixes: 604ba230 ("net: prestera: flower template support")
Signed-off-by: NJiasheng Jiang <jiasheng@iscas.ac.cn>
Reviewed-by: Taras Chornyi<tchornyi@marvell.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/marvell/prestera/prestera_acl.c

@@ -178,10 +178,14 @@ prestera_acl_ruleset_create(struct prestera_acl *acl,
 	return ERR_PTR(err);
 }
 
-void prestera_acl_ruleset_keymask_set(struct prestera_acl_ruleset *ruleset,
-				      void *keymask)
+int prestera_acl_ruleset_keymask_set(struct prestera_acl_ruleset *ruleset,
+				     void *keymask)
 {
 	ruleset->keymask = kmemdup(keymask, ACL_KEYMASK_SIZE, GFP_KERNEL);
+	if (!ruleset->keymask)
+		return -ENOMEM;
+
+	return 0;
 }
 
 int prestera_acl_ruleset_offload(struct prestera_acl_ruleset *ruleset)

drivers/net/ethernet/marvell/prestera/prestera_acl.h

@@ -185,8 +185,8 @@ struct prestera_acl_ruleset *
 prestera_acl_ruleset_lookup(struct prestera_acl *acl,
 			    struct prestera_flow_block *block,
 			    u32 chain_index);
-void prestera_acl_ruleset_keymask_set(struct prestera_acl_ruleset *ruleset,
-				      void *keymask);
+int prestera_acl_ruleset_keymask_set(struct prestera_acl_ruleset *ruleset,
+				     void *keymask);
 bool prestera_acl_ruleset_is_offload(struct prestera_acl_ruleset *ruleset);
 int prestera_acl_ruleset_offload(struct prestera_acl_ruleset *ruleset);
 void prestera_acl_ruleset_put(struct prestera_acl_ruleset *ruleset);

drivers/net/ethernet/marvell/prestera/prestera_flower.c

@@ -452,7 +452,9 @@ int prestera_flower_tmplt_create(struct prestera_flow_block *block,
 	}
 
 	/* preserve keymask/template to this ruleset */
-	prestera_acl_ruleset_keymask_set(ruleset, rule.re_key.match.mask);
+	err = prestera_acl_ruleset_keymask_set(ruleset, rule.re_key.match.mask);
+	if (err)
+		goto err_ruleset_keymask_set;
 
 	/* skip error, as it is not possible to reject template operation,
 	 * so, keep the reference to the ruleset for rules to be added
@@ -468,6 +470,8 @@ int prestera_flower_tmplt_create(struct prestera_flow_block *block,
 	list_add_rcu(&template->list, &block->template_list);
 	return 0;
 
+err_ruleset_keymask_set:
+	prestera_acl_ruleset_put(ruleset);
 err_ruleset_get:
 	kfree(template);
 err_malloc: