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Diffstat (limited to 'net/netfilter/nf_tables_api.c')
-rw-r--r--net/netfilter/nf_tables_api.c126
1 files changed, 86 insertions, 40 deletions
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 4aa01c1253b1..7e63b481cc86 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -578,35 +578,45 @@ __nf_tables_chain_type_lookup(const struct nlattr *nla, u8 family)
return NULL;
}
-/*
- * Loading a module requires dropping mutex that guards the transaction.
- * A different client might race to start a new transaction meanwhile. Zap the
- * list of pending transaction and then restore it once the mutex is grabbed
- * again. Users of this function return EAGAIN which implicitly triggers the
- * transaction abort path to clean up the list of pending transactions.
- */
+struct nft_module_request {
+ struct list_head list;
+ char module[MODULE_NAME_LEN];
+ bool done;
+};
+
#ifdef CONFIG_MODULES
-static void nft_request_module(struct net *net, const char *fmt, ...)
+static int nft_request_module(struct net *net, const char *fmt, ...)
{
char module_name[MODULE_NAME_LEN];
- LIST_HEAD(commit_list);
+ struct nft_module_request *req;
va_list args;
int ret;
- list_splice_init(&net->nft.commit_list, &commit_list);
-
va_start(args, fmt);
ret = vsnprintf(module_name, MODULE_NAME_LEN, fmt, args);
va_end(args);
if (ret >= MODULE_NAME_LEN)
- return;
+ return 0;
- mutex_unlock(&net->nft.commit_mutex);
- request_module("%s", module_name);
- mutex_lock(&net->nft.commit_mutex);
+ list_for_each_entry(req, &net->nft.module_list, list) {
+ if (!strcmp(req->module, module_name)) {
+ if (req->done)
+ return 0;
- WARN_ON_ONCE(!list_empty(&net->nft.commit_list));
- list_splice(&commit_list, &net->nft.commit_list);
+ /* A request to load this module already exists. */
+ return -EAGAIN;
+ }
+ }
+
+ req = kmalloc(sizeof(*req), GFP_KERNEL);
+ if (!req)
+ return -ENOMEM;
+
+ req->done = false;
+ strlcpy(req->module, module_name, MODULE_NAME_LEN);
+ list_add_tail(&req->list, &net->nft.module_list);
+
+ return -EAGAIN;
}
#endif
@@ -630,10 +640,9 @@ nf_tables_chain_type_lookup(struct net *net, const struct nlattr *nla,
lockdep_nfnl_nft_mutex_not_held();
#ifdef CONFIG_MODULES
if (autoload) {
- nft_request_module(net, "nft-chain-%u-%.*s", family,
- nla_len(nla), (const char *)nla_data(nla));
- type = __nf_tables_chain_type_lookup(nla, family);
- if (type != NULL)
+ if (nft_request_module(net, "nft-chain-%u-%.*s", family,
+ nla_len(nla),
+ (const char *)nla_data(nla)) == -EAGAIN)
return ERR_PTR(-EAGAIN);
}
#endif
@@ -2341,9 +2350,8 @@ static const struct nft_expr_type *__nft_expr_type_get(u8 family,
static int nft_expr_type_request_module(struct net *net, u8 family,
struct nlattr *nla)
{
- nft_request_module(net, "nft-expr-%u-%.*s", family,
- nla_len(nla), (char *)nla_data(nla));
- if (__nft_expr_type_get(family, nla))
+ if (nft_request_module(net, "nft-expr-%u-%.*s", family,
+ nla_len(nla), (char *)nla_data(nla)) == -EAGAIN)
return -EAGAIN;
return 0;
@@ -2369,9 +2377,9 @@ static const struct nft_expr_type *nft_expr_type_get(struct net *net,
if (nft_expr_type_request_module(net, family, nla) == -EAGAIN)
return ERR_PTR(-EAGAIN);
- nft_request_module(net, "nft-expr-%.*s",
- nla_len(nla), (char *)nla_data(nla));
- if (__nft_expr_type_get(family, nla))
+ if (nft_request_module(net, "nft-expr-%.*s",
+ nla_len(nla),
+ (char *)nla_data(nla)) == -EAGAIN)
return ERR_PTR(-EAGAIN);
}
#endif
@@ -2462,9 +2470,10 @@ static int nf_tables_expr_parse(const struct nft_ctx *ctx,
err = PTR_ERR(ops);
#ifdef CONFIG_MODULES
if (err == -EAGAIN)
- nft_expr_type_request_module(ctx->net,
- ctx->family,
- tb[NFTA_EXPR_NAME]);
+ if (nft_expr_type_request_module(ctx->net,
+ ctx->family,
+ tb[NFTA_EXPR_NAME]) != -EAGAIN)
+ err = -ENOENT;
#endif
goto err1;
}
@@ -3301,8 +3310,7 @@ nft_select_set_ops(const struct nft_ctx *ctx,
lockdep_nfnl_nft_mutex_not_held();
#ifdef CONFIG_MODULES
if (list_empty(&nf_tables_set_types)) {
- nft_request_module(ctx->net, "nft-set");
- if (!list_empty(&nf_tables_set_types))
+ if (nft_request_module(ctx->net, "nft-set") == -EAGAIN)
return ERR_PTR(-EAGAIN);
}
#endif
@@ -5428,8 +5436,7 @@ nft_obj_type_get(struct net *net, u32 objtype)
lockdep_nfnl_nft_mutex_not_held();
#ifdef CONFIG_MODULES
if (type == NULL) {
- nft_request_module(net, "nft-obj-%u", objtype);
- if (__nft_obj_type_get(objtype))
+ if (nft_request_module(net, "nft-obj-%u", objtype) == -EAGAIN)
return ERR_PTR(-EAGAIN);
}
#endif
@@ -6002,8 +6009,7 @@ nft_flowtable_type_get(struct net *net, u8 family)
lockdep_nfnl_nft_mutex_not_held();
#ifdef CONFIG_MODULES
if (type == NULL) {
- nft_request_module(net, "nf-flowtable-%u", family);
- if (__nft_flowtable_type_get(family))
+ if (nft_request_module(net, "nf-flowtable-%u", family) == -EAGAIN)
return ERR_PTR(-EAGAIN);
}
#endif
@@ -7005,6 +7011,18 @@ static void nft_chain_del(struct nft_chain *chain)
list_del_rcu(&chain->list);
}
+static void nf_tables_module_autoload_cleanup(struct net *net)
+{
+ struct nft_module_request *req, *next;
+
+ WARN_ON_ONCE(!list_empty(&net->nft.commit_list));
+ list_for_each_entry_safe(req, next, &net->nft.module_list, list) {
+ WARN_ON_ONCE(!req->done);
+ list_del(&req->list);
+ kfree(req);
+ }
+}
+
static void nf_tables_commit_release(struct net *net)
{
struct nft_trans *trans;
@@ -7017,6 +7035,7 @@ static void nf_tables_commit_release(struct net *net)
* to prevent expensive synchronize_rcu() in commit phase.
*/
if (list_empty(&net->nft.commit_list)) {
+ nf_tables_module_autoload_cleanup(net);
mutex_unlock(&net->nft.commit_mutex);
return;
}
@@ -7031,6 +7050,7 @@ static void nf_tables_commit_release(struct net *net)
list_splice_tail_init(&net->nft.commit_list, &nf_tables_destroy_list);
spin_unlock(&nf_tables_destroy_list_lock);
+ nf_tables_module_autoload_cleanup(net);
mutex_unlock(&net->nft.commit_mutex);
schedule_work(&trans_destroy_work);
@@ -7222,6 +7242,26 @@ static int nf_tables_commit(struct net *net, struct sk_buff *skb)
return 0;
}
+static void nf_tables_module_autoload(struct net *net)
+{
+ struct nft_module_request *req, *next;
+ LIST_HEAD(module_list);
+
+ list_splice_init(&net->nft.module_list, &module_list);
+ mutex_unlock(&net->nft.commit_mutex);
+ list_for_each_entry_safe(req, next, &module_list, list) {
+ if (req->done) {
+ list_del(&req->list);
+ kfree(req);
+ } else {
+ request_module("%s", req->module);
+ req->done = true;
+ }
+ }
+ mutex_lock(&net->nft.commit_mutex);
+ list_splice(&module_list, &net->nft.module_list);
+}
+
static void nf_tables_abort_release(struct nft_trans *trans)
{
switch (trans->msg_type) {
@@ -7251,7 +7291,7 @@ static void nf_tables_abort_release(struct nft_trans *trans)
kfree(trans);
}
-static int __nf_tables_abort(struct net *net)
+static int __nf_tables_abort(struct net *net, bool autoload)
{
struct nft_trans *trans, *next;
struct nft_trans_elem *te;
@@ -7373,6 +7413,11 @@ static int __nf_tables_abort(struct net *net)
nf_tables_abort_release(trans);
}
+ if (autoload)
+ nf_tables_module_autoload(net);
+ else
+ nf_tables_module_autoload_cleanup(net);
+
return 0;
}
@@ -7381,9 +7426,9 @@ static void nf_tables_cleanup(struct net *net)
nft_validate_state_update(net, NFT_VALIDATE_SKIP);
}
-static int nf_tables_abort(struct net *net, struct sk_buff *skb)
+static int nf_tables_abort(struct net *net, struct sk_buff *skb, bool autoload)
{
- int ret = __nf_tables_abort(net);
+ int ret = __nf_tables_abort(net, autoload);
mutex_unlock(&net->nft.commit_mutex);
@@ -7978,6 +8023,7 @@ static int __net_init nf_tables_init_net(struct net *net)
{
INIT_LIST_HEAD(&net->nft.tables);
INIT_LIST_HEAD(&net->nft.commit_list);
+ INIT_LIST_HEAD(&net->nft.module_list);
mutex_init(&net->nft.commit_mutex);
net->nft.base_seq = 1;
net->nft.validate_state = NFT_VALIDATE_SKIP;
@@ -7989,7 +8035,7 @@ static void __net_exit nf_tables_exit_net(struct net *net)
{
mutex_lock(&net->nft.commit_mutex);
if (!list_empty(&net->nft.commit_list))
- __nf_tables_abort(net);
+ __nf_tables_abort(net, false);
__nft_release_tables(net);
mutex_unlock(&net->nft.commit_mutex);
WARN_ON_ONCE(!list_empty(&net->nft.tables));
generated by cgit (git 2.34.1) at 2024-05-04 11:35:20 +0000