netfilter: nf_tables: make all set structs const

They do not need to be writeable anymore.

v2: remove left-over __read_mostly annotation in set_pipapo.c (Stefano)
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

include/net/netfilter/nf_tables.h

@@ -385,14 +385,10 @@ struct nft_set_ops {
  *      struct nft_set_type - nf_tables set type
  *
  *      @ops: set ops for this type
- *      @list: used internally
- *      @owner: module reference
  *      @features: features supported by the implementation
  */
 struct nft_set_type {
 	const struct nft_set_ops	ops;
-	struct list_head		list;
-	struct module			*owner;
 	u32				features;
 };
 #define to_set_type(o) container_of(o, struct nft_set_type, ops)

include/net/netfilter/nf_tables_core.h

@@ -69,12 +69,12 @@ extern const struct nft_expr_ops nft_payload_fast_ops;
 extern struct static_key_false nft_counters_enabled;
 extern struct static_key_false nft_trace_enabled;
 
-extern struct nft_set_type nft_set_rhash_type;
-extern struct nft_set_type nft_set_hash_type;
-extern struct nft_set_type nft_set_hash_fast_type;
-extern struct nft_set_type nft_set_rbtree_type;
-extern struct nft_set_type nft_set_bitmap_type;
-extern struct nft_set_type nft_set_pipapo_type;
+extern const struct nft_set_type nft_set_rhash_type;
+extern const struct nft_set_type nft_set_hash_type;
+extern const struct nft_set_type nft_set_hash_fast_type;
+extern const struct nft_set_type nft_set_rbtree_type;
+extern const struct nft_set_type nft_set_bitmap_type;
+extern const struct nft_set_type nft_set_pipapo_type;
 
 struct nft_expr;
 struct nft_regs;

net/netfilter/nf_tables_api.c

@@ -3344,11 +3344,6 @@ nft_select_set_ops(const struct nft_ctx *ctx,
 			break;
 		}
 
-		if (!try_module_get(type->owner))
-			continue;
-		if (bops != NULL)
-			module_put(to_set_type(bops)->owner);
-
 		bops = ops;
 		best = est;
 	}
@@ -4047,10 +4042,8 @@ static int nf_tables_newset(struct net *net, struct sock *nlsk,
 		size = ops->privsize(nla, &desc);
 
 	set = kvzalloc(sizeof(*set) + size + udlen, GFP_KERNEL);
-	if (!set) {
-		err = -ENOMEM;
-		goto err1;
-	}
+	if (!set)
+		return -ENOMEM;
 
 	name = nla_strdup(nla[NFTA_SET_NAME], GFP_KERNEL);
 	if (!name) {
@@ -4109,8 +4102,6 @@ static int nf_tables_newset(struct net *net, struct sock *nlsk,
 	kfree(set->name);
 err2:
 	kvfree(set);
-err1:
-	module_put(to_set_type(ops)->owner);
 	return err;
 }
 
@@ -4120,7 +4111,6 @@ static void nft_set_destroy(struct nft_set *set)
 		return;
 
 	set->ops->destroy(set);
-	module_put(to_set_type(set->ops)->owner);
 	kfree(set->name);
 	kvfree(set);
 }

net/netfilter/nft_set_bitmap.c

@@ -293,8 +293,7 @@ static bool nft_bitmap_estimate(const struct nft_set_desc *desc, u32 features,
 	return true;
 }
 
-struct nft_set_type nft_set_bitmap_type __read_mostly = {
-	.owner		= THIS_MODULE,
+const struct nft_set_type nft_set_bitmap_type = {
 	.ops		= {
 		.privsize	= nft_bitmap_privsize,
 		.elemsize	= offsetof(struct nft_bitmap_elem, ext),

net/netfilter/nft_set_hash.c

@@ -662,8 +662,7 @@ static bool nft_hash_fast_estimate(const struct nft_set_desc *desc, u32 features
 	return true;
 }
 
-struct nft_set_type nft_set_rhash_type __read_mostly = {
-	.owner		= THIS_MODULE,
+const struct nft_set_type nft_set_rhash_type = {
 	.features	= NFT_SET_MAP | NFT_SET_OBJECT |
 			  NFT_SET_TIMEOUT | NFT_SET_EVAL,
 	.ops		= {
@@ -686,8 +685,7 @@ struct nft_set_type nft_set_rhash_type __read_mostly = {
 	},
 };
 
-struct nft_set_type nft_set_hash_type __read_mostly = {
-	.owner		= THIS_MODULE,
+const struct nft_set_type nft_set_hash_type = {
 	.features	= NFT_SET_MAP | NFT_SET_OBJECT,
 	.ops		= {
 		.privsize       = nft_hash_privsize,
@@ -706,8 +704,7 @@ struct nft_set_type nft_set_hash_type __read_mostly = {
 	},
 };
 
-struct nft_set_type nft_set_hash_fast_type __read_mostly = {
-	.owner		= THIS_MODULE,
+const struct nft_set_type nft_set_hash_fast_type = {
 	.features	= NFT_SET_MAP | NFT_SET_OBJECT,
 	.ops		= {
 		.privsize       = nft_hash_privsize,

net/netfilter/nft_set_pipapo.c

@@ -2081,8 +2081,7 @@ static void nft_pipapo_gc_init(const struct nft_set *set)
 	priv->last_gc = jiffies;
 }
 
-struct nft_set_type nft_set_pipapo_type __read_mostly = {
-	.owner		= THIS_MODULE,
+const struct nft_set_type nft_set_pipapo_type = {
 	.features	= NFT_SET_INTERVAL | NFT_SET_MAP | NFT_SET_OBJECT |
 			  NFT_SET_TIMEOUT,
 	.ops		= {

net/netfilter/nft_set_rbtree.c

@@ -481,8 +481,7 @@ static bool nft_rbtree_estimate(const struct nft_set_desc *desc, u32 features,
 	return true;
 }
 
-struct nft_set_type nft_set_rbtree_type __read_mostly = {
-	.owner		= THIS_MODULE,
+const struct nft_set_type nft_set_rbtree_type = {
 	.features	= NFT_SET_INTERVAL | NFT_SET_MAP | NFT_SET_OBJECT | NFT_SET_TIMEOUT,
 	.ops		= {
 		.privsize	= nft_rbtree_privsize,