kernel/linux.git/include/net/netfilter, branch v4.9.113

netfilter: nat: Revert "netfilter: nat: convert nat bysrc hash to rhashtable"

2017-11-18T10:22:24+00:00

commit e1bf1687740ce1a3598a1c5e452b852ff2190682 upstream. This reverts commit 870190a9ec9075205c0fa795a09fa931694a3ff1. It was not a good idea. The custom hash table was a much better fit for this purpose. A fast lookup is not essential, in fact for most cases there is no lookup at all because original tuple is not taken and can be used as-is. What needs to be fast is insertion and deletion. rhlist removal however requires a rhlist walk. We can have thousands of entries in such a list if source port/addresses are reused for multiple flows, if this happens removal requests are so expensive that deletions of a few thousand flows can take several seconds(!). The advantages that we got from rhashtable are: 1) table auto-sizing 2) multiple locks 1) would be nice to have, but it is not essential as we have at most one lookup per new flow, so even a million flows in the bysource table are not a problem compared to current deletion cost. 2) is easy to add to custom hash table. I tried to add hlist_node to rhlist to speed up rhltable_remove but this isn't doable without changing semantics. rhltable_remove_fast will check that the to-be-deleted object is part of the table and that requires a list walk that we want to avoid. Furthermore, using hlist_node increases size of struct rhlist_head, which in turn increases nf_conn size. Link: https://bugzilla.kernel.org/show_bug.cgi?id=196821 Reported-by: Ivan Babrou Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso Signed-off-by: Greg Kroah-Hartman

netfilter: nf_tables: set pktinfo->thoff at AH header if found

2017-10-08T08:26:11+00:00

[ Upstream commit 568af6de058cb2b0c5b98d98ffcf37cdc6bc38a7 ] Phil Sutter reports that IPv6 AH header matching is broken. From userspace, nft generates bytecode that expects to find the AH header at NFT_PAYLOAD_TRANSPORT_HEADER both for IPv4 and IPv6. However, pktinfo->thoff is set to the inner header after the AH header in IPv6, while in IPv4 pktinfo->thoff points to the AH header indeed. This behaviour is inconsistent. This patch fixes this problem by updating ipv6_find_hdr() to get the IP6_FH_F_AUTH flag so this function stops at the AH header, so both IPv4 and IPv6 pktinfo->thoff point to the AH header. This is also inconsistent when trying to match encapsulated headers: 1) A packet that looks like IPv4 + AH + TCP dport 22 will *not* match. 2) A packet that looks like IPv6 + AH + TCP dport 22 will match. Reported-by: Phil Sutter Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

netfilter: nat: fix crash when conntrack entry is re-used

2016-11-24T13:43:35+00:00

Stas Nichiporovich reports oops in nf_nat_bysource_cmp(), trying to access nf_conn struct at address 0xffffffffffffff50. This is the result of fetching a null rhash list (struct embedded at offset 176; 0 - 176 gets us ...fff50). The problem is that conntrack entries are allocated from a SLAB_DESTROY_BY_RCU cache, i.e. entries can be free'd and reused on another cpu while nf nat bysource hash access the same conntrack entry. Freeing is fine (we hold rcu read lock); zeroing rhlist_head isn't. -> Move the rhlist struct outside of the memset()-inited area. Fixes: 7c9664351980aaa6a ("netfilter: move nat hlist_head to nf_conn") Reported-by: Stas Nichiporovich Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso

netfilter: nf_tables: fix inconsistent element expiration calculation

2016-11-24T13:43:34+00:00

As Liping Zhang reports, after commit a8b1e36d0d1d ("netfilter: nft_dynset: fix element timeout for HZ != 1000"), priv->timeout was stored in jiffies, while set->timeout was stored in milliseconds. This is inconsistent and incorrect. Firstly, we already call msecs_to_jiffies in nft_set_elem_init, so priv->timeout will be converted to jiffies twice. Secondly, if the user did not specify the NFTA_DYNSET_TIMEOUT attr, set->timeout will be used, but we forget to call msecs_to_jiffies when do update elements. Fix this by using jiffies internally for traditional sets and doing the conversions to/from msec when interacting with userspace - as dynset already does. This is preferable to doing the conversions, when elements are inserted or updated, because this can happen very frequently on busy dynsets. Fixes: a8b1e36d0d1d ("netfilter: nft_dynset: fix element timeout for HZ != 1000") Reported-by: Liping Zhang Signed-off-by: Anders K. Pedersen Acked-by: Liping Zhang Signed-off-by: Pablo Neira Ayuso

netfilter: nat: switch to new rhlist interface

2016-11-24T13:43:34+00:00

I got offlist bug report about failing connections and high cpu usage. This happens because we hit 'elasticity' checks in rhashtable that refuses bucket list exceeding 16 entries. The nat bysrc hash unfortunately needs to insert distinct objects that share same key and are identical (have same source tuple), this cannot be avoided. Switch to the rhlist interface which is designed for this. The nulls_base is removed here, I don't think its needed: A (unlikely) false positive results in unneeded port clash resolution, a false negative results in packet drop during conntrack confirmation, when we try to insert the duplicate into main conntrack hash table. Tested by adding multiple ip addresses to host, then adding iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE ... and then creating multiple connections, from same source port but different addresses: for i in $(seq 2000 2032);do nc -p 1234 192.168.7.1 $i > /dev/null & done (all of these then get hashed to same bysource slot) Then, to test that nat conflict resultion is working: nc -s 10.0.0.1 -p 1234 192.168.7.1 2000 nc -s 10.0.0.2 -p 1234 192.168.7.1 2000 tcp .. src=10.0.0.1 dst=192.168.7.1 sport=1234 dport=2000 src=192.168.7.1 dst=192.168.7.10 sport=2000 dport=1024 [ASSURED] tcp .. src=10.0.0.2 dst=192.168.7.1 sport=1234 dport=2000 src=192.168.7.1 dst=192.168.7.10 sport=2000 dport=1025 [ASSURED] tcp .. src=192.168.7.10 dst=192.168.7.1 sport=1234 dport=2000 src=192.168.7.1 dst=192.168.7.10 sport=2000 dport=1234 [ASSURED] tcp .. src=192.168.7.10 dst=192.168.7.1 sport=1234 dport=2001 src=192.168.7.1 dst=192.168.7.10 sport=2001 dport=1234 [ASSURED] [..] -> nat altered source ports to 1024 and 1025, respectively. This can also be confirmed on destination host which shows ESTAB 0 0 192.168.7.1:2000 192.168.7.10:1024 ESTAB 0 0 192.168.7.1:2000 192.168.7.10:1025 ESTAB 0 0 192.168.7.1:2000 192.168.7.10:1234 Cc: Herbert Xu Fixes: 870190a9ec907 ("netfilter: nat: convert nat bysrc hash to rhashtable") Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso

netfilter: conntrack: avoid excess memory allocation

2016-10-27T16:29:02+00:00

This is now a fixed-size extension, so we don't need to pass a variable alloc size. This (harmless) error results in allocating 32 instead of the needed 16 bytes for this extension as the size gets passed twice. Fixes: 23014011ba420 ("netfilter: conntrack: support a fixed size of 128 distinct labels") Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso

netfilter: nf_tables: fix type mismatch with error return from nft_parse_u32_check

2016-10-27T16:29:01+00:00

Commit 36b701fae12ac ("netfilter: nf_tables: validate maximum value of u32 netlink attributes") introduced nft_parse_u32_check with a return value of "unsigned int", yet on error it returns "-ERANGE". This patch corrects the mismatch by changing the return value to "int", which happens to match the actual users of nft_parse_u32_check already. Found by Coverity, CID 1373930. Note that commit 21a9e0f1568ea ("netfilter: nft_exthdr: fix error handling in nft_exthdr_init()) attempted to address the issue, but did not address the return type of nft_parse_u32_check. Signed-off-by: John W. Linville Cc: Laura Garcia Liebana Cc: Pablo Neira Ayuso Cc: Dan Carpenter Fixes: 36b701fae12ac ("netfilter: nf_tables: validate maximum value...") Signed-off-by: Pablo Neira Ayuso

netfilter: nf_tables: fix leak when expr clone fail

2016-10-27T16:20:45+00:00

When nft_expr_clone failed, a series of problems will happen: 1. module refcnt will leak, we call __module_get at the beginning but we forget to put it back if ops->clone returns fail 2. memory will be leaked, if clone fail, we just return NULL and forget to free the alloced element 3. set->nelems will become incorrect when set->size is specified. If clone fail, we should decrease the set->nelems Now this patch fixes these problems. And fortunately, clone fail will only happen on counter expression when memory is exhausted. Fixes: 086f332167d6 ("netfilter: nf_tables: add clone interface to expression operations") Signed-off-by: Liping Zhang Signed-off-by: Pablo Neira Ayuso

netfilter: merge fixup for "nf_tables_netdev: remove redundant ip_hdr assignment"

2016-10-06T00:25:48+00:00

Signed-off-by: Stephen Rothwell Acked-by: Pablo Neira Ayuso Signed-off-by: David S. Miller

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

2016-09-25T21:34:19+00:00

Conflicts: net/netfilter/core.c net/netfilter/nf_tables_netdev.c Resolve two conflicts before pull request for David's net-next tree: 1) Between c73c24849011 ("netfilter: nf_tables_netdev: remove redundant ip_hdr assignment") from the net tree and commit ddc8b6027ad0 ("netfilter: introduce nft_set_pktinfo_{ipv4, ipv6}_validate()"). 2) Between e8bffe0cf964 ("net: Add _nf_(un)register_hooks symbols") and Aaron Conole's patches to replace list_head with single linked list. Signed-off-by: Pablo Neira Ayuso