From 442fad9423b78319e0019a7f5047eddf3317afbc Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Mon, 11 Feb 2013 23:22:38 +0000 Subject: [PATCH 1/3] netfilter: ctnetlink: don't permit ct creation with random tuple Userspace can cause kernel panic by not specifying orig/reply tuple: kernel will create a tuple with random stack values. Problem is that tuple.dst.dir will be random, too, which causes nf_ct_tuplehash_to_ctrack() to return garbage. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_conntrack_netlink.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index 627b0e50b238..a081915e0531 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -1705,6 +1705,9 @@ ctnetlink_new_conntrack(struct sock *ctnl, struct sk_buff *skb, if (nlh->nlmsg_flags & NLM_F_CREATE) { enum ip_conntrack_events events; + if (!cda[CTA_TUPLE_ORIG] || !cda[CTA_TUPLE_REPLY]) + return -EINVAL; + ct = ctnetlink_create_conntrack(net, zone, cda, &otuple, &rtuple, u3); if (IS_ERR(ct)) From 6e2f0aa8cf8892868bf2c19349cb5d7c407f690d Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Tue, 12 Feb 2013 05:59:53 +0000 Subject: [PATCH 2/3] netfilter: nf_ct_helper: don't discard helper if it is actually the same commit (32f5376 netfilter: nf_ct_helper: disable automatic helper re-assignment of different type) broke transparent proxy scenarios. For example, initial helper lookup might yield "ftp" (dport 21), while re-lookup after REDIRECT yields "ftp-2121". This causes the autoassign code to toss the ftp helper, even though these are just different instances of the same helper. Change the test to check for the helper function address instead of the helper address, as suggested by Pablo. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_conntrack_helper.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/netfilter/nf_conntrack_helper.c b/net/netfilter/nf_conntrack_helper.c index 884f2b39319a..91527d5ba018 100644 --- a/net/netfilter/nf_conntrack_helper.c +++ b/net/netfilter/nf_conntrack_helper.c @@ -236,7 +236,9 @@ int __nf_ct_try_assign_helper(struct nf_conn *ct, struct nf_conn *tmpl, /* We only allow helper re-assignment of the same sort since * we cannot reallocate the helper extension area. */ - if (help->helper != helper) { + struct nf_conntrack_helper *tmp = rcu_dereference(help->helper); + + if (tmp && tmp->help != helper->help) { RCU_INIT_POINTER(help->helper, NULL); goto out; } From 894e2ac82bd0029adce7ad6c8d25501fdd82c994 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Michal=20Kube=C4=8Dek?= Date: Tue, 12 Feb 2013 23:46:09 +0000 Subject: [PATCH 3/3] netfilter: nf_ct_reasm: fix per-netns sysctl initialization Adjusting of data pointers in net/netfilter/nf_conntrack_frag6_* sysctl table for other namespaces points to wrong netns_frags structure and has reversed order of entries. Problem introduced by commit c038a767cd69 in 3.7-rc1 Signed-off-by: Michal Kubecek Signed-off-by: Pablo Neira Ayuso --- net/ipv6/netfilter/nf_conntrack_reasm.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c index 3dacecc99065..0156d07d732f 100644 --- a/net/ipv6/netfilter/nf_conntrack_reasm.c +++ b/net/ipv6/netfilter/nf_conntrack_reasm.c @@ -97,9 +97,9 @@ static int nf_ct_frag6_sysctl_register(struct net *net) if (table == NULL) goto err_alloc; - table[0].data = &net->ipv6.frags.high_thresh; - table[1].data = &net->ipv6.frags.low_thresh; - table[2].data = &net->ipv6.frags.timeout; + table[0].data = &net->nf_frag.frags.timeout; + table[1].data = &net->nf_frag.frags.low_thresh; + table[2].data = &net->nf_frag.frags.high_thresh; } hdr = register_net_sysctl(net, "net/netfilter", table);