This patch fixes a silent out-of-bound read possibility that was present
because of the misuse of this function.
Mostly it was called with a struct udphdr *hp which had only the udphdr
part linearized by the skb_header_pointer, however
nf_tproxy_get_sock_v{4,6} uses it as a tcphdr pointer, so some reads for
tcp specific attributes may be invalid.
Fixes: a583636a83ea ("inet: refactor inet[6]_lookup functions to take skb")
Signed-off-by: Máté Eckl <ecklm94@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nft_compat relies on xt_request_find_match to increment refcount of the module that provides the match/target. The (builtin) icmp matches did't set the module owner so it was possible to rmmod ip(6)tables while icmp extensions were still in use. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pablo Neira Ayuso says:
====================
Netfilter/IPVS fixes for net
The following patchset contains Netfilter/IPVS fixes for your net tree:
1) Reject non-null terminated helper names from xt_CT, from Gao Feng.
2) Fix KASAN splat due to out-of-bound access from commit phase, from
Alexey Kodanev.
3) Missing conntrack hook registration on IPVS FTP helper, from Julian
Anastasov.
4) Incorrect skbuff allocation size in bridge nft_reject, from Taehee Yoo.
5) Fix inverted check on packet xmit to non-local addresses, also from
Julian.
6) Fix ebtables alignment compat problems, from Alin Nastac.
7) Hook mask checks are not correct in xt_set, from Serhey Popovych.
8) Fix timeout listing of element in ipsets, from Jozsef.
9) Cap maximum timeout value in ipset, also from Jozsef.
10) Don't allow family option for hash:mac sets, from Florent Fourcot.
11) Restrict ebtables to work with NFPROTO_BRIDGE targets only, this
Florian.
12) Another bug reported by KASAN in the rbtree set backend, from
Taehee Yoo.
13) Missing __IPS_MAX_BIT update doesn't include IPS_OFFLOAD_BIT.
From Gao Feng.
14) Missing initialization of match/target in ebtables, from Florian
Westphal.
15) Remove useless nft_dup.h file in include path, from C. Labbe.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
syzbot reports following splat:
BUG: KMSAN: uninit-value in ebt_stp_mt_check+0x24b/0x450
net/bridge/netfilter/ebt_stp.c:162
ebt_stp_mt_check+0x24b/0x450 net/bridge/netfilter/ebt_stp.c:162
xt_check_match+0x1438/0x1650 net/netfilter/x_tables.c:506
ebt_check_match net/bridge/netfilter/ebtables.c:372 [inline]
ebt_check_entry net/bridge/netfilter/ebtables.c:702 [inline]
The uninitialised access is
xt_mtchk_param->nft_compat
... which should be set to 0.
Fix it by zeroing the struct beforehand, same for tgchk.
ip(6)tables targetinfo uses c99-style initialiser, so no change
needed there.
Reported-by: syzbot+da4494182233c23a5fcf@syzkaller.appspotmail.com
Fixes: 55917a21d0cc0 ("netfilter: x_tables: add context to know if extension runs from nft_compat")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The extracted functions will likely be usefull to implement tproxy support in nf_tables. Extrancted functions: - nf_tproxy_sk_is_transparent - nf_tproxy_laddr4 - nf_tproxy_handle_time_wait4 - nf_tproxy_get_sock_v4 - nf_tproxy_laddr6 - nf_tproxy_handle_time_wait6 - nf_tproxy_get_sock_v6 (nf_)tproxy_handle_time_wait6 also needed some refactor as its current implementation was xtables-specific. Signed-off-by: Máté Eckl <ecklm94@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Instead of using extra modules for these, turn the config options into an implicit dependency that adds masq feature to the protocol specific nf_nat module. before: text data bss dec hex filename 2001 860 4 2865 b31 net/ipv4/netfilter/nf_nat_masquerade_ipv4.ko 5579 780 2 6361 18d9 net/ipv4/netfilter/nf_nat_ipv4.ko 2860 836 8 3704 e78 net/ipv6/netfilter/nf_nat_masquerade_ipv6.ko 6648 780 2 7430 1d06 net/ipv6/netfilter/nf_nat_ipv6.ko after: text data bss dec hex filename 7245 872 8 8125 1fbd net/ipv4/netfilter/nf_nat_ipv4.ko 9165 848 12 10025 2729 net/ipv6/netfilter/nf_nat_ipv6.ko Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pablo Neira Ayuso says:
====================
Netfilter updates for net-next
The following patchset contains Netfilter updates for your net-next
tree, they are:
1) Remove obsolete nf_log tracing from nf_tables, from Florian Westphal.
2) Add support for map lookups to numgen, random and hash expressions,
from Laura Garcia.
3) Allow to register nat hooks for iptables and nftables at the same
time. Patchset from Florian Westpha.
4) Timeout support for rbtree sets.
5) ip6_rpfilter works needs interface for link-local addresses, from
Vincent Bernat.
6) Add nf_ct_hook and nf_nat_hook structures and use them.
7) Do not drop packets on packets raceing to insert conntrack entries
into hashes, this is particularly a problem in nfqueue setups.
8) Address fallout from xt_osf separation to nf_osf, patches
from Florian Westphal and Fernando Mancera.
9) Remove reference to struct nft_af_info, which doesn't exist anymore.
From Taehee Yoo.
This batch comes with is a conflict between 25fd386e0bc0 ("netfilter:
core: add missing __rcu annotation") in your tree and 2c205dd3981f
("netfilter: add struct nf_nat_hook and use it") coming in this batch.
This conflict can be solved by leaving the __rcu tag on
__netfilter_net_init() - added by 25fd386e0bc0 - and remove all code
related to nf_nat_decode_session_hook - which is gone after
2c205dd3981f, as described by:
diff --cc net/netfilter/core.c
index e0ae4aae96f5,206fb2c4c319..168af54db975
--- a/net/netfilter/core.c
+++ b/net/netfilter/core.c
@@@ -611,7 -580,13 +611,8 @@@ const struct nf_conntrack_zone nf_ct_zo
EXPORT_SYMBOL_GPL(nf_ct_zone_dflt);
#endif /* CONFIG_NF_CONNTRACK */
- static void __net_init __netfilter_net_init(struct nf_hook_entries **e, int max)
-#ifdef CONFIG_NF_NAT_NEEDED
-void (*nf_nat_decode_session_hook)(struct sk_buff *, struct flowi *);
-EXPORT_SYMBOL(nf_nat_decode_session_hook);
-#endif
-
+ static void __net_init
+ __netfilter_net_init(struct nf_hook_entries __rcu **e, int max)
{
int h;
I can also merge your net-next tree into nf-next, solve the conflict and
resend the pull request if you prefer so.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently the packet rewrite and instantiation of nat NULL bindings
happens from the protocol specific nat backend.
Invocation occurs either via ip(6)table_nat or the nf_tables nat chain type.
Invocation looks like this (simplified):
NF_HOOK()
|
`---iptable_nat
|
`---> nf_nat_l3proto_ipv4 -> nf_nat_packet
|
new packet? pass skb though iptables nat chain
|
`---> iptable_nat: ipt_do_table
In nft case, this looks the same (nft_chain_nat_ipv4 instead of
iptable_nat).
This is a problem for two reasons:
1. Can't use iptables nat and nf_tables nat at the same time,
as the first user adds a nat binding (nf_nat_l3proto_ipv4 adds a
NULL binding if do_table() did not find a matching nat rule so we
can detect post-nat tuple collisions).
2. If you use e.g. nft_masq, snat, redir, etc. uses must also register
an empty base chain so that the nat core gets called fro NF_HOOK()
to do the reverse translation, which is neither obvious nor user
friendly.
After this change, the base hook gets registered not from iptable_nat or
nftables nat hooks, but from the l3 nat core.
iptables/nft nat base hooks get registered with the nat core instead:
NF_HOOK()
|
`---> nf_nat_l3proto_ipv4 -> nf_nat_packet
|
new packet? pass skb through iptables/nftables nat chains
|
+-> iptables_nat: ipt_do_table
+-> nft nat chain x
`-> nft nat chain y
The nat core deals with null bindings and reverse translation.
When no mapping exists, it calls the registered nat lookup hooks until
one creates a new mapping.
If both iptables and nftables nat hooks exist, the first matching
one is used (i.e., higher priority wins).
Also, nft users do not need to create empty nat hooks anymore,
nat core always registers the base hooks that take care of reverse/reply
translation.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Will be used in followup patch when nat types no longer use nf_register_net_hook() but will instead register with the nat core. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The ip(6)tables nat table is currently receiving skbs from the netfilter core, after a followup patch skbs will be coming from the netfilter nat core instead, so the table is no longer backed by normal hook_ops. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>