From b1e93a68ca41e7e73766f95ba32ca05cf9052e15 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Mon, 16 Mar 2009 15:06:42 +0100 Subject: netfilter: conntrack: don't deliver events for racy packets This patch skips the delivery of conntrack events if the packet was drop due to a race condition in the conntrack insertion. Signed-off-by: Pablo Neira Ayuso Signed-off-by: Patrick McHardy --- include/net/netfilter/nf_conntrack_core.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/include/net/netfilter/nf_conntrack_core.h b/include/net/netfilter/nf_conntrack_core.h index c25068e3851..5a449b44ba3 100644 --- a/include/net/netfilter/nf_conntrack_core.h +++ b/include/net/netfilter/nf_conntrack_core.h @@ -62,7 +62,8 @@ static inline int nf_conntrack_confirm(struct sk_buff *skb) if (ct && ct != &nf_conntrack_untracked) { if (!nf_ct_is_confirmed(ct) && !nf_ct_is_dying(ct)) ret = __nf_conntrack_confirm(skb); - nf_ct_deliver_cached_events(ct); + if (likely(ret == NF_ACCEPT)) + nf_ct_deliver_cached_events(ct); } return ret; } -- cgit v1.2.3-70-g09d2 From 626ba8fbac9156a94a80be46ffd2f2ce9e4e89a0 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Mon, 16 Mar 2009 15:50:51 +0100 Subject: netfilter: ctnetlink: fix crash during expectation creation This patch fixes a possible crash due to the missing initialization of the expectation class when nf_ct_expect_related() is called. Reported-by: BORBELY Zoltan Signed-off-by: Pablo Neira Ayuso Signed-off-by: Patrick McHardy --- net/netfilter/nf_conntrack_netlink.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c index cb78aa00399..ed6d873ad38 100644 --- a/net/netfilter/nf_conntrack_netlink.c +++ b/net/netfilter/nf_conntrack_netlink.c @@ -1780,6 +1780,7 @@ ctnetlink_create_expect(struct nlattr *cda[], u_int8_t u3, u32 pid, int report) goto out; } + exp->class = 0; exp->expectfn = NULL; exp->flags = 0; exp->master = ct; -- cgit v1.2.3-70-g09d2 From ec8d540969da9a70790e9028d57b5b577dd7aa77 Mon Sep 17 00:00:00 2001 From: Christoph Paasch Date: Mon, 16 Mar 2009 15:51:29 +0100 Subject: netfilter: conntrack: fix dropping packet after l4proto->packet() We currently use the negative value in the conntrack code to encode the packet verdict in the error. As NF_DROP is equal to 0, inverting NF_DROP makes no sense and, as a result, no packets are ever dropped. Signed-off-by: Christoph Paasch Signed-off-by: Pablo Neira Ayuso Signed-off-by: Patrick McHardy --- net/netfilter/nf_conntrack_core.c | 2 +- net/netfilter/nf_conntrack_proto_tcp.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/net/netfilter/nf_conntrack_core.c b/net/netfilter/nf_conntrack_core.c index 90ce9ddb945..f4935e344b6 100644 --- a/net/netfilter/nf_conntrack_core.c +++ b/net/netfilter/nf_conntrack_core.c @@ -726,7 +726,7 @@ nf_conntrack_in(struct net *net, u_int8_t pf, unsigned int hooknum, NF_CT_ASSERT(skb->nfct); ret = l4proto->packet(ct, skb, dataoff, ctinfo, pf, hooknum); - if (ret < 0) { + if (ret <= 0) { /* Invalid: inverse of the return code tells * the netfilter core what to do */ pr_debug("nf_conntrack_in: Can't track with proto module\n"); diff --git a/net/netfilter/nf_conntrack_proto_tcp.c b/net/netfilter/nf_conntrack_proto_tcp.c index a1edb9c1ade..f3fd154d1dd 100644 --- a/net/netfilter/nf_conntrack_proto_tcp.c +++ b/net/netfilter/nf_conntrack_proto_tcp.c @@ -859,7 +859,7 @@ static int tcp_packet(struct nf_conn *ct, */ if (nf_ct_kill(ct)) return -NF_REPEAT; - return -NF_DROP; + return NF_DROP; } /* Fall through */ case TCP_CONNTRACK_IGNORE: @@ -892,7 +892,7 @@ static int tcp_packet(struct nf_conn *ct, nf_log_packet(pf, 0, skb, NULL, NULL, NULL, "nf_ct_tcp: killing out of sync session "); nf_ct_kill(ct); - return -NF_DROP; + return NF_DROP; } ct->proto.tcp.last_index = index; ct->proto.tcp.last_dir = dir; -- cgit v1.2.3-70-g09d2 From d1238d5337e8e53cddea77c2a26d26b6eb5a982f Mon Sep 17 00:00:00 2001 From: Christoph Paasch Date: Mon, 16 Mar 2009 15:52:11 +0100 Subject: netfilter: conntrack: check for NEXTHDR_NONE before header sanity checking NEXTHDR_NONE doesn't has an IPv6 option header, so the first check for the length will always fail and results in a confusing message "too short" if debugging enabled. With this patch, we check for NEXTHDR_NONE before length sanity checkings are done. Signed-off-by: Christoph Paasch Signed-off-by: Pablo Neira Ayuso Signed-off-by: Patrick McHardy --- net/ipv6/netfilter/nf_conntrack_reasm.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c index ed4d79a9e4a..058a5e4a60c 100644 --- a/net/ipv6/netfilter/nf_conntrack_reasm.c +++ b/net/ipv6/netfilter/nf_conntrack_reasm.c @@ -528,14 +528,14 @@ find_prev_fhdr(struct sk_buff *skb, u8 *prevhdrp, int *prevhoff, int *fhoff) if (!ipv6_ext_hdr(nexthdr)) { return -1; } - if (len < (int)sizeof(struct ipv6_opt_hdr)) { - pr_debug("too short\n"); - return -1; - } if (nexthdr == NEXTHDR_NONE) { pr_debug("next header is none\n"); return -1; } + if (len < (int)sizeof(struct ipv6_opt_hdr)) { + pr_debug("too short\n"); + return -1; + } if (skb_copy_bits(skb, start, &hdr, sizeof(hdr))) BUG(); if (nexthdr == NEXTHDR_AUTH) -- cgit v1.2.3-70-g09d2