diff options
author | David S. Miller <davem@davemloft.net> | 2019-03-11 16:14:14 -0700 |
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committer | David S. Miller <davem@davemloft.net> | 2019-03-11 16:14:14 -0700 |
commit | ab0891f5d820a863a24ee410b04ac10424b9bb03 (patch) | |
tree | 21c57caa76bb0105e575e1abbfceb4f330574cf6 /net | |
parent | ee74d0bd4325efb41e38affe5955f920ed973f23 (diff) | |
parent | b8b27498659c65034032af79842913844a6cc79a (diff) | |
download | linux-ab0891f5d820a863a24ee410b04ac10424b9bb03.tar.bz2 |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contains Netfilter fixes for your net tree:
1) Fix list corruption in device notifier in the masquerade
infrastructure, from Florian Westphal.
2) Fix double-free of sets and use-after-free when deleting elements.
3) Don't bogusly return EBUSY when removing a set after flush command.
4) Use-after-free in dynamically allocate operations.
5) Don't report a new ruleset generation to userspace if transaction
list is empty, this invalidates the userspace cache innecessarily.
From Florian Westphal.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
-rw-r--r-- | net/netfilter/nf_nat_masquerade.c | 35 | ||||
-rw-r--r-- | net/netfilter/nf_tables_api.c | 54 | ||||
-rw-r--r-- | net/netfilter/nft_dynset.c | 13 | ||||
-rw-r--r-- | net/netfilter/nft_lookup.c | 13 | ||||
-rw-r--r-- | net/netfilter/nft_objref.c | 13 |
5 files changed, 92 insertions, 36 deletions
diff --git a/net/netfilter/nf_nat_masquerade.c b/net/netfilter/nf_nat_masquerade.c index 86fa4dcc63c5..d85c4d902e7b 100644 --- a/net/netfilter/nf_nat_masquerade.c +++ b/net/netfilter/nf_nat_masquerade.c @@ -11,7 +11,8 @@ #include <net/netfilter/ipv6/nf_nat_masquerade.h> static DEFINE_MUTEX(masq_mutex); -static unsigned int masq_refcnt __read_mostly; +static unsigned int masq_refcnt4 __read_mostly; +static unsigned int masq_refcnt6 __read_mostly; unsigned int nf_nat_masquerade_ipv4(struct sk_buff *skb, unsigned int hooknum, @@ -141,8 +142,13 @@ int nf_nat_masquerade_ipv4_register_notifier(void) int ret = 0; mutex_lock(&masq_mutex); + if (WARN_ON_ONCE(masq_refcnt4 == UINT_MAX)) { + ret = -EOVERFLOW; + goto out_unlock; + } + /* check if the notifier was already set */ - if (++masq_refcnt > 1) + if (++masq_refcnt4 > 1) goto out_unlock; /* Register for device down reports */ @@ -160,7 +166,7 @@ int nf_nat_masquerade_ipv4_register_notifier(void) err_unregister: unregister_netdevice_notifier(&masq_dev_notifier); err_dec: - masq_refcnt--; + masq_refcnt4--; out_unlock: mutex_unlock(&masq_mutex); return ret; @@ -171,7 +177,7 @@ void nf_nat_masquerade_ipv4_unregister_notifier(void) { mutex_lock(&masq_mutex); /* check if the notifier still has clients */ - if (--masq_refcnt > 0) + if (--masq_refcnt4 > 0) goto out_unlock; unregister_netdevice_notifier(&masq_dev_notifier); @@ -321,25 +327,23 @@ int nf_nat_masquerade_ipv6_register_notifier(void) int ret = 0; mutex_lock(&masq_mutex); - /* check if the notifier is already set */ - if (++masq_refcnt > 1) + if (WARN_ON_ONCE(masq_refcnt6 == UINT_MAX)) { + ret = -EOVERFLOW; goto out_unlock; + } - ret = register_netdevice_notifier(&masq_dev_notifier); - if (ret) - goto err_dec; + /* check if the notifier is already set */ + if (++masq_refcnt6 > 1) + goto out_unlock; ret = register_inet6addr_notifier(&masq_inet6_notifier); if (ret) - goto err_unregister; + goto err_dec; mutex_unlock(&masq_mutex); return ret; - -err_unregister: - unregister_netdevice_notifier(&masq_dev_notifier); err_dec: - masq_refcnt--; + masq_refcnt6--; out_unlock: mutex_unlock(&masq_mutex); return ret; @@ -350,11 +354,10 @@ void nf_nat_masquerade_ipv6_unregister_notifier(void) { mutex_lock(&masq_mutex); /* check if the notifier still has clients */ - if (--masq_refcnt > 0) + if (--masq_refcnt6 > 0) goto out_unlock; unregister_inet6addr_notifier(&masq_inet6_notifier); - unregister_netdevice_notifier(&masq_dev_notifier); out_unlock: mutex_unlock(&masq_mutex); } diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index faf6bd10a19f..513f93118604 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -142,7 +142,7 @@ static void nft_set_trans_bind(const struct nft_ctx *ctx, struct nft_set *set) list_for_each_entry_reverse(trans, &net->nft.commit_list, list) { if (trans->msg_type == NFT_MSG_NEWSET && nft_trans_set(trans) == set) { - nft_trans_set_bound(trans) = true; + set->bound = true; break; } } @@ -2162,9 +2162,11 @@ err1: static void nf_tables_expr_destroy(const struct nft_ctx *ctx, struct nft_expr *expr) { + const struct nft_expr_type *type = expr->ops->type; + if (expr->ops->destroy) expr->ops->destroy(ctx, expr); - module_put(expr->ops->type->owner); + module_put(type->owner); } struct nft_expr *nft_expr_init(const struct nft_ctx *ctx, @@ -3672,6 +3674,9 @@ err1: static void nft_set_destroy(struct nft_set *set) { + if (WARN_ON(set->use > 0)) + return; + set->ops->destroy(set); module_put(to_set_type(set->ops)->owner); kfree(set->name); @@ -3712,7 +3717,7 @@ static int nf_tables_delset(struct net *net, struct sock *nlsk, NL_SET_BAD_ATTR(extack, attr); return PTR_ERR(set); } - if (!list_empty(&set->bindings) || + if (set->use || (nlh->nlmsg_flags & NLM_F_NONREC && atomic_read(&set->nelems) > 0)) { NL_SET_BAD_ATTR(extack, attr); return -EBUSY; @@ -3742,6 +3747,9 @@ int nf_tables_bind_set(const struct nft_ctx *ctx, struct nft_set *set, struct nft_set_binding *i; struct nft_set_iter iter; + if (set->use == UINT_MAX) + return -EOVERFLOW; + if (!list_empty(&set->bindings) && nft_set_is_anonymous(set)) return -EBUSY; @@ -3769,6 +3777,7 @@ bind: binding->chain = ctx->chain; list_add_tail_rcu(&binding->list, &set->bindings); nft_set_trans_bind(ctx, set); + set->use++; return 0; } @@ -3788,6 +3797,25 @@ void nf_tables_unbind_set(const struct nft_ctx *ctx, struct nft_set *set, } EXPORT_SYMBOL_GPL(nf_tables_unbind_set); +void nf_tables_deactivate_set(const struct nft_ctx *ctx, struct nft_set *set, + struct nft_set_binding *binding, + enum nft_trans_phase phase) +{ + switch (phase) { + case NFT_TRANS_PREPARE: + set->use--; + return; + case NFT_TRANS_ABORT: + case NFT_TRANS_RELEASE: + set->use--; + /* fall through */ + default: + nf_tables_unbind_set(ctx, set, binding, + phase == NFT_TRANS_COMMIT); + } +} +EXPORT_SYMBOL_GPL(nf_tables_deactivate_set); + void nf_tables_destroy_set(const struct nft_ctx *ctx, struct nft_set *set) { if (list_empty(&set->bindings) && nft_set_is_anonymous(set)) @@ -6536,6 +6564,11 @@ static int nf_tables_commit(struct net *net, struct sk_buff *skb) struct nft_chain *chain; struct nft_table *table; + if (list_empty(&net->nft.commit_list)) { + mutex_unlock(&net->nft.commit_mutex); + return 0; + } + /* 0. Validate ruleset, otherwise roll back for error reporting. */ if (nf_tables_validate(net) < 0) return -EAGAIN; @@ -6709,8 +6742,7 @@ static void nf_tables_abort_release(struct nft_trans *trans) nf_tables_rule_destroy(&trans->ctx, nft_trans_rule(trans)); break; case NFT_MSG_NEWSET: - if (!nft_trans_set_bound(trans)) - nft_set_destroy(nft_trans_set(trans)); + nft_set_destroy(nft_trans_set(trans)); break; case NFT_MSG_NEWSETELEM: nft_set_elem_destroy(nft_trans_elem_set(trans), @@ -6783,8 +6815,11 @@ static int __nf_tables_abort(struct net *net) break; case NFT_MSG_NEWSET: trans->ctx.table->use--; - if (!nft_trans_set_bound(trans)) - list_del_rcu(&nft_trans_set(trans)->list); + if (nft_trans_set(trans)->bound) { + nft_trans_destroy(trans); + break; + } + list_del_rcu(&nft_trans_set(trans)->list); break; case NFT_MSG_DELSET: trans->ctx.table->use++; @@ -6792,8 +6827,11 @@ static int __nf_tables_abort(struct net *net) nft_trans_destroy(trans); break; case NFT_MSG_NEWSETELEM: + if (nft_trans_elem_set(trans)->bound) { + nft_trans_destroy(trans); + break; + } te = (struct nft_trans_elem *)trans->data; - te->set->ops->remove(net, te->set, &te->elem); atomic_dec(&te->set->nelems); break; diff --git a/net/netfilter/nft_dynset.c b/net/netfilter/nft_dynset.c index a8a74a16f9c4..e461007558e8 100644 --- a/net/netfilter/nft_dynset.c +++ b/net/netfilter/nft_dynset.c @@ -240,11 +240,15 @@ static void nft_dynset_deactivate(const struct nft_ctx *ctx, { struct nft_dynset *priv = nft_expr_priv(expr); - if (phase == NFT_TRANS_PREPARE) - return; + nf_tables_deactivate_set(ctx, priv->set, &priv->binding, phase); +} + +static void nft_dynset_activate(const struct nft_ctx *ctx, + const struct nft_expr *expr) +{ + struct nft_dynset *priv = nft_expr_priv(expr); - nf_tables_unbind_set(ctx, priv->set, &priv->binding, - phase == NFT_TRANS_COMMIT); + priv->set->use++; } static void nft_dynset_destroy(const struct nft_ctx *ctx, @@ -292,6 +296,7 @@ static const struct nft_expr_ops nft_dynset_ops = { .eval = nft_dynset_eval, .init = nft_dynset_init, .destroy = nft_dynset_destroy, + .activate = nft_dynset_activate, .deactivate = nft_dynset_deactivate, .dump = nft_dynset_dump, }; diff --git a/net/netfilter/nft_lookup.c b/net/netfilter/nft_lookup.c index 14496da5141d..161c3451a747 100644 --- a/net/netfilter/nft_lookup.c +++ b/net/netfilter/nft_lookup.c @@ -127,11 +127,15 @@ static void nft_lookup_deactivate(const struct nft_ctx *ctx, { struct nft_lookup *priv = nft_expr_priv(expr); - if (phase == NFT_TRANS_PREPARE) - return; + nf_tables_deactivate_set(ctx, priv->set, &priv->binding, phase); +} + +static void nft_lookup_activate(const struct nft_ctx *ctx, + const struct nft_expr *expr) +{ + struct nft_lookup *priv = nft_expr_priv(expr); - nf_tables_unbind_set(ctx, priv->set, &priv->binding, - phase == NFT_TRANS_COMMIT); + priv->set->use++; } static void nft_lookup_destroy(const struct nft_ctx *ctx, @@ -222,6 +226,7 @@ static const struct nft_expr_ops nft_lookup_ops = { .size = NFT_EXPR_SIZE(sizeof(struct nft_lookup)), .eval = nft_lookup_eval, .init = nft_lookup_init, + .activate = nft_lookup_activate, .deactivate = nft_lookup_deactivate, .destroy = nft_lookup_destroy, .dump = nft_lookup_dump, diff --git a/net/netfilter/nft_objref.c b/net/netfilter/nft_objref.c index 79ef074c18ca..457a9ceb46af 100644 --- a/net/netfilter/nft_objref.c +++ b/net/netfilter/nft_objref.c @@ -162,11 +162,15 @@ static void nft_objref_map_deactivate(const struct nft_ctx *ctx, { struct nft_objref_map *priv = nft_expr_priv(expr); - if (phase == NFT_TRANS_PREPARE) - return; + nf_tables_deactivate_set(ctx, priv->set, &priv->binding, phase); +} + +static void nft_objref_map_activate(const struct nft_ctx *ctx, + const struct nft_expr *expr) +{ + struct nft_objref_map *priv = nft_expr_priv(expr); - nf_tables_unbind_set(ctx, priv->set, &priv->binding, - phase == NFT_TRANS_COMMIT); + priv->set->use++; } static void nft_objref_map_destroy(const struct nft_ctx *ctx, @@ -183,6 +187,7 @@ static const struct nft_expr_ops nft_objref_map_ops = { .size = NFT_EXPR_SIZE(sizeof(struct nft_objref_map)), .eval = nft_objref_map_eval, .init = nft_objref_map_init, + .activate = nft_objref_map_activate, .deactivate = nft_objref_map_deactivate, .destroy = nft_objref_map_destroy, .dump = nft_objref_map_dump, |