[PATCH nf] netfilter: ctnetlink: memleak in filter initialization error path

[PATCH nf] netfilter: ctnetlink: memleak in filter initialization error path

[Pablo Neira Ayuso]

Release the filter object in case of error.

Fixes: cb8aa9a3affb ("netfilter: ctnetlink: add kernel side filtering for dump")
Reported-by: syzbot+38b8b548a851a01793c5@syzkaller.appspotmail.com
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/nf_conntrack_netlink.c | 32 +++++++++++++++++++---------
 1 file changed, 22 insertions(+), 10 deletions(-)

diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index d7bd8b1f27d5..832eabecfbdd 100644
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -939,7 +939,8 @@ ctnetlink_alloc_filter(const struct nlattr * const cda[], u8 family)
 			filter->mark.mask = 0xffffffff;
 		}
 	} else if (cda[CTA_MARK_MASK]) {
-		return ERR_PTR(-EINVAL);
+		err = -EINVAL;
+		goto err_filter;
 	}
 #endif
 	if (!cda[CTA_FILTER])
@@ -947,15 +948,17 @@ ctnetlink_alloc_filter(const struct nlattr * const cda[], u8 family)
 
 	err = ctnetlink_parse_zone(cda[CTA_ZONE], &filter->zone);
 	if (err < 0)
-		return ERR_PTR(err);
+		goto err_filter;
 
 	err = ctnetlink_parse_filter(cda[CTA_FILTER], filter);
 	if (err < 0)
-		return ERR_PTR(err);
+		goto err_filter;
 
 	if (filter->orig_flags) {
-		if (!cda[CTA_TUPLE_ORIG])
-			return ERR_PTR(-EINVAL);
+		if (!cda[CTA_TUPLE_ORIG]) {
+			err = -EINVAL;
+			goto err_filter;
+		}
 
 		err = ctnetlink_parse_tuple_filter(cda, &filter->orig,
 						   CTA_TUPLE_ORIG,
@@ -963,23 +966,32 @@ ctnetlink_alloc_filter(const struct nlattr * const cda[], u8 family)
 						   &filter->zone,
 						   filter->orig_flags);
 		if (err < 0)
-			return ERR_PTR(err);
+			goto err_filter;
 	}
 
 	if (filter->reply_flags) {
-		if (!cda[CTA_TUPLE_REPLY])
-			return ERR_PTR(-EINVAL);
+		if (!cda[CTA_TUPLE_REPLY]) {
+			err = -EINVAL;
+			goto err_filter;
+		}
 
 		err = ctnetlink_parse_tuple_filter(cda, &filter->reply,
 						   CTA_TUPLE_REPLY,
 						   filter->family,
 						   &filter->zone,
 						   filter->orig_flags);
-		if (err < 0)
-			return ERR_PTR(err);
+		if (err < 0) {
+			err = -EINVAL;
+			goto err_filter;
+		}
 	}
 
 	return filter;
+
+err_filter:
+	kfree(filter);
+
+	return ERR_PTR(err);
 }
 
 static bool ctnetlink_needs_filter(u8 family, const struct nlattr * const *cda)
-- 
2.20.1

[PATCH nf] netfilter: nf_tables: hook list memleak in flowtable deletion

[Pablo Neira Ayuso]

After looking up for the flowtable hooks that need to be removed,
release the hook objects in the deletion list. The error path needs to
released these hook objects too.

Reported-by: syzbot+eb9d5924c51d6d59e094@syzkaller.appspotmail.com
Fixes: abadb2f865d7 ("netfilter: nf_tables: delete devices from flowtable")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/nf_tables_api.c | 31 ++++++++++++++++++++++++-------
 1 file changed, 24 insertions(+), 7 deletions(-)

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 073aa1051d43..5792e9dcd9bc 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -6550,12 +6550,22 @@ static int nf_tables_newflowtable(struct net *net, struct sock *nlsk,
 	return err;
 }
 
+static void nft_flowtable_hook_release(struct nft_flowtable_hook *flowtable_hook)
+{
+	struct nft_hook *this, *next;
+
+	list_for_each_entry_safe(this, next, &flowtable_hook->list, list) {
+		list_del(&this->list);
+		kfree(this);
+	}
+}
+
 static int nft_delflowtable_hook(struct nft_ctx *ctx,
 				 struct nft_flowtable *flowtable)
 {
 	const struct nlattr * const *nla = ctx->nla;
 	struct nft_flowtable_hook flowtable_hook;
-	struct nft_hook *this, *next, *hook;
+	struct nft_hook *this, *hook;
 	struct nft_trans *trans;
 	int err;
 
@@ -6564,33 +6574,40 @@ static int nft_delflowtable_hook(struct nft_ctx *ctx,
 	if (err < 0)
 		return err;
 
-	list_for_each_entry_safe(this, next, &flowtable_hook.list, list) {
+	list_for_each_entry(this, &flowtable_hook.list, list) {
 		hook = nft_hook_list_find(&flowtable->hook_list, this);
 		if (!hook) {
 			err = -ENOENT;
 			goto err_flowtable_del_hook;
 		}
 		hook->inactive = true;
-		list_del(&this->list);
-		kfree(this);
 	}
 
 	trans = nft_trans_alloc(ctx, NFT_MSG_DELFLOWTABLE,
 				sizeof(struct nft_trans_flowtable));
-	if (!trans)
-		return -ENOMEM;
+	if (!trans) {
+		err = -ENOMEM;
+		goto err_flowtable_del_hook;
+	}
 
 	nft_trans_flowtable(trans) = flowtable;
 	nft_trans_flowtable_update(trans) = true;
 	INIT_LIST_HEAD(&nft_trans_flowtable_hooks(trans));
+	nft_flowtable_hook_release(&flowtable_hook);
 
 	list_add_tail(&trans->list, &ctx->net->nft.commit_list);
 
 	return 0;
 
 err_flowtable_del_hook:
-	list_for_each_entry(hook, &flowtable_hook.list, list)
+	list_for_each_entry(this, &flowtable->hook_list, list) {
+		hook = nft_hook_list_find(&flowtable->hook_list, this);
+		if (!hook)
+			break;
+
 		hook->inactive = false;
+	}
+	nft_flowtable_hook_release(&flowtable_hook);
 
 	return err;
 }
-- 
2.20.1