linux/net/netfilter, branch v3.2.41

netfilter: Validate the sequence number of dataless ACK packets as well

2012-12-06T11:20:10Z

commit 4a70bbfaef0361d27272629d1a250a937edcafe4 upstream. We spare nothing by not validating the sequence number of dataless ACK packets and enabling it makes harder off-path attacks. See: "Reflection scan: an Off-Path Attack on TCP" by Jan Wrobel, http://arxiv.org/abs/1201.2074 Signed-off-by: Jozsef Kadlecsik Signed-off-by: Pablo Neira Ayuso Signed-off-by: Ben Hutchings

netfilter: Mark SYN/ACK packets as invalid from original direction

2012-12-06T11:20:10Z

commit 64f509ce71b08d037998e93dd51180c19b2f464c upstream. Clients should not send such packets. By accepting them, we open up a hole by wich ephemeral ports can be discovered in an off-path attack. See: "Reflection scan: an Off-Path Attack on TCP" by Jan Wrobel, http://arxiv.org/abs/1201.2074 Signed-off-by: Jozsef Kadlecsik Signed-off-by: Pablo Neira Ayuso Signed-off-by: Ben Hutchings

netfilter: nf_conntrack: fix racy timer handling with reliable events

2012-10-30T23:27:08Z

commit 5b423f6a40a0327f9d40bc8b97ce9be266f74368 upstream. Existing code assumes that del_timer returns true for alive conntrack entries. However, this is not true if reliable events are enabled. In that case, del_timer may return true for entries that were just inserted in the dying list. Note that packets / ctnetlink may hold references to conntrack entries that were just inserted to such list. This patch fixes the issue by adding an independent timer for event delivery. This increases the size of the ecache extension. Still we can revisit this later and use variable size extensions to allocate this area on demand. Tested-by: Oliver Smith Signed-off-by: Pablo Neira Ayuso Acked-by: David Miller Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings

netfilter: xt_limit: have r->cost != 0 case work

2012-10-17T02:50:09Z

commit 82e6bfe2fbc4d48852114c4f979137cd5bf1d1a8 upstream. Commit v2.6.19-rc1~1272^2~41 tells us that r->cost != 0 can happen when a running state is saved to userspace and then reinstated from there. Make sure that private xt_limit area is initialized with correct values. Otherwise, random matchings due to use of uninitialized memory. Signed-off-by: Jan Engelhardt Signed-off-by: Pablo Neira Ayuso Signed-off-by: Ben Hutchings

netfilter: limit, hashlimit: avoid duplicated inline

2012-10-17T02:50:08Z

commit 7a909ac70f6b0823d9f23a43f19598d4b57ac901 upstream. credit_cap can be set to credit, which avoids inlining user2credits twice. Also, remove inline keyword and let compiler decide. old: 684 192 0 876 36c net/netfilter/xt_limit.o 4927 344 32 5303 14b7 net/netfilter/xt_hashlimit.o now: 668 192 0 860 35c net/netfilter/xt_limit.o 4793 344 32 5169 1431 net/netfilter/xt_hashlimit.o Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Ben Hutchings

netfilter: nf_ct_expect: fix possible access to uninitialized timer

2012-10-17T02:50:06Z

commit 2614f86490122bf51eb7c12ec73927f1900f4e7d upstream. In __nf_ct_expect_check, the function refresh_timer returns 1 if a matching expectation is found and its timer is successfully refreshed. This results in nf_ct_expect_related returning 0. Note that at this point: - the passed expectation is not inserted in the expectation table and its timer was not initialized, since we have refreshed one matching/existing expectation. - nf_ct_expect_alloc uses kmem_cache_alloc, so the expectation timer is in some undefined state just after the allocation, until it is appropriately initialized. This can be a problem for the SIP helper during the expectation addition: ... if (nf_ct_expect_related(rtp_exp) == 0) { if (nf_ct_expect_related(rtcp_exp) != 0) nf_ct_unexpect_related(rtp_exp); ... Note that nf_ct_expect_related(rtp_exp) may return 0 for the timer refresh case that is detailed above. Then, if nf_ct_unexpect_related(rtcp_exp) returns != 0, nf_ct_unexpect_related(rtp_exp) is called, which does: spin_lock_bh(&nf_conntrack_lock); if (del_timer(&exp->timeout)) { nf_ct_unlink_expect(exp); nf_ct_expect_put(exp); } spin_unlock_bh(&nf_conntrack_lock); Note that del_timer always returns false if the timer has been initialized. However, the timer was not initialized since setup_timer was not called, therefore, the expectation timer remains in some undefined state. If I'm not missing anything, this may lead to the removal an unexistent expectation. To fix this, the optimization that allows refreshing an expectation is removed. Now nf_conntrack_expect_related looks more consistent to me since it always add the expectation in case that it returns success. Thanks to Patrick McHardy for participating in the discussion of this patch. I think this may be the source of the problem described by: http://marc.info/?l=netfilter-devel&m=134073514719421&w=2 Reported-by: Rafal Fitt Acked-by: Patrick McHardy Signed-off-by: Pablo Neira Ayuso Signed-off-by: Ben Hutchings

ipvs: fix info leak in getsockopt(IP_VS_SO_GET_TIMEOUT)

2012-09-19T14:04:54Z

[ Upstream commit 2d8a041b7bfe1097af21441cb77d6af95f4f4680 ] If at least one of CONFIG_IP_VS_PROTO_TCP or CONFIG_IP_VS_PROTO_UDP is not set, __ip_vs_get_timeouts() does not fully initialize the structure that gets copied to userland and that for leaks up to 12 bytes of kernel stack. Add an explicit memset(0) before passing the structure to __ip_vs_get_timeouts() to avoid the info leak. Signed-off-by: Mathias Krause Cc: Wensong Zhang Cc: Simon Horman Cc: Julian Anastasov Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings

ipvs: fix matching of fwmark templates during scheduling

2012-03-01T00:31:19Z

commit e0aac52e17a3db68fe2ceae281780a70fc69957f upstream. Commit f11017ec2d1859c661f4e2b12c4a8d250e1f47cf (2.6.37) moved the fwmark variable in subcontext that is invalidated before reaching the ip_vs_ct_in_get call. As vaddr is provided as pointer in the param structure make sure the fwmark variable is in same context. As the fwmark templates can not be matched, more and more template connections are created and the controlled connections can not go to single real server. Signed-off-by: Julian Anastasov Signed-off-by: Simon Horman Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman

net: reintroduce missing rcu_assign_pointer() calls

2012-02-03T17:22:20Z

[ Upstream commit cf778b00e96df6d64f8e21b8395d1f8a859ecdc7 ] commit a9b3cd7f32 (rcu: convert uses of rcu_assign_pointer(x, NULL) to RCU_INIT_POINTER) did a lot of incorrect changes, since it did a complete conversion of rcu_assign_pointer(x, y) to RCU_INIT_POINTER(x, y). We miss needed barriers, even on x86, when y is not NULL. Signed-off-by: Eric Dumazet CC: Stephen Hemminger CC: Paul E. McKenney Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

netfilter: ctnetlink: fix timeout calculation

2011-12-31T15:59:04Z

The sanity check (timeout < 0) never works; the dividend is unsigned and so is the division, which should have been a signed division. long timeout = (ct->timeout.expires - jiffies) / HZ; if (timeout < 0) timeout = 0; This patch converts the time values to signed for the division. Signed-off-by: Xi Wang Signed-off-by: Pablo Neira Ayuso