The compat layer needs to parse untrusted input (the ruleset)
to translate it to a 64bit compatible format.
We had a number of bugs in this department in the past, so allow users
to turn this feature off.
Add CONFIG_NETFILTER_XTABLES_COMPAT kconfig knob and make it default to y
to keep existing behaviour.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Update batch callbacks to use the nfnl_info structure. Rename one
clashing info variable to expr_info.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add a new structure to reduce callback footprint and to facilite
extensions of the nfnetlink callback interface in the future.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
iptable_x modules rely on 'struct net' to contain a pointer to the
table that should be evaluated.
In order to remove these pointers from struct net, pass them via
the 'priv' pointer in a similar fashion as nf_tables passes the
rule data.
To do that, duplicate the nf_hook_info array passed in from the
iptable_x modules, update the ops->priv pointers of the copy to
refer to the table and then change the hookfn implementations to
just pass the 'priv' argument to the traverser.
After this patch, the xt_table pointers can already be removed
from struct net.
However, changes to struct net result in re-compile of the entire
network stack, so do the removal after arptables and ip6tables
have been converted as well.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This will be used to obtain the xt_table struct given address family and
table name.
Followup patches will reduce the number of direct accesses to the xt_table
structures via net->ipv{4,6}.ip(6)table_{nat,mangle,...} pointers, then
remove them.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This removes the only reference of net->nfnl outside of the nfnetlink
module. This allows to move net->nfnl to net_generic infra.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch adds a helper function to set up the netlink and nfnetlink headers.
Update existing codebase to use it.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
struct ip_set is declared twice. One is declared at 79th line,
so remove the duplicate.
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Acked-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When a new table value was assigned, it was followed by a write memory
barrier. This ensured that all writes before this point would complete
before any writes after this point. However, to determine whether the
rules are unused, the sequence counter is read. To ensure that all
writes have been done before these reads, a full memory barrier is
needed, not just a write memory barrier. The same argument applies when
incrementing the counter, before the rules are read.
Changing to using smp_mb() instead of smp_wmb() fixes the kernel panic
reported in cc00bcaa58 (which is still present), while still
maintaining the same speed of replacing tables.
The smb_mb() barriers potentially slow the packet path, however testing
has shown no measurable change in performance on a 4-core MIPS64
platform.
Fixes: 7f5c6d4f66 ("netfilter: get rid of atomic ops in fast path")
Signed-off-by: Mark Tomlinson <mark.tomlinson@alliedtelesis.co.nz>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This reverts commit cc00bcaa58.
This (and the preceding) patch basically re-implemented the RCU
mechanisms of patch 784544739a. That patch was replaced because of the
performance problems that it created when replacing tables. Now, we have
the same issue: the call to synchronize_rcu() makes replacing tables
slower by as much as an order of magnitude.
Prior to using RCU a script calling "iptables" approx. 200 times was
taking 1.16s. With RCU this increased to 11.59s.
Revert these patches and fix the issue in a different way.
Signed-off-by: Mark Tomlinson <mark.tomlinson@alliedtelesis.co.nz>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
xdp_return_frame_bulk() needs to pass a xdp_buff
to __xdp_return().
strlcpy got converted to strscpy but here it makes no
functional difference, so just keep the right code.
Conflicts:
net/netfilter/nf_tables_api.c
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When running concurrent iptables rules replacement with data, the per CPU
sequence count is checked after the assignment of the new information.
The sequence count is used to synchronize with the packet path without the
use of any explicit locking. If there are any packets in the packet path using
the table information, the sequence count is incremented to an odd value and
is incremented to an even after the packet process completion.
The new table value assignment is followed by a write memory barrier so every
CPU should see the latest value. If the packet path has started with the old
table information, the sequence counter will be odd and the iptables
replacement will wait till the sequence count is even prior to freeing the
old table info.
However, this assumes that the new table information assignment and the memory
barrier is actually executed prior to the counter check in the replacement
thread. If CPU decides to execute the assignment later as there is no user of
the table information prior to the sequence check, the packet path in another
CPU may use the old table information. The replacement thread would then free
the table information under it leading to a use after free in the packet
processing context-
Unable to handle kernel NULL pointer dereference at virtual
address 000000000000008e
pc : ip6t_do_table+0x5d0/0x89c
lr : ip6t_do_table+0x5b8/0x89c
ip6t_do_table+0x5d0/0x89c
ip6table_filter_hook+0x24/0x30
nf_hook_slow+0x84/0x120
ip6_input+0x74/0xe0
ip6_rcv_finish+0x7c/0x128
ipv6_rcv+0xac/0xe4
__netif_receive_skb+0x84/0x17c
process_backlog+0x15c/0x1b8
napi_poll+0x88/0x284
net_rx_action+0xbc/0x23c
__do_softirq+0x20c/0x48c
This could be fixed by forcing instruction order after the new table
information assignment or by switching to RCU for the synchronization.
Fixes: 80055dab5d ("netfilter: x_tables: make xt_replace_table wait until old rules are not used anymore")
Reported-by: Sean Tranchetti <stranche@codeaurora.org>
Reported-by: kernel test robot <lkp@intel.com>
Suggested-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The parameter defines the upper limit in any hash bucket at adding new entries
from userspace - if the limit would be exceeded, ipset doubles the hash size
and rehashes. It means the set may consume more memory but gives faster
evaluation at matching in the set.
Signed-off-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
If userspace does not include the trailing end of batch message, then
nfnetlink aborts the transaction. This allows to check that ruleset
updates trigger no errors.
After this patch, invoking this command from the prerouting chain:
# nft -c add rule x y fib saddr . oif type local
fails since oif is not supported there.
This patch fixes the lack of rule validation from the abort/check path
to catch configuration errors such as the one above.
Fixes: a654de8fdc ("netfilter: nf_tables: fix chain dependency validation")
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 net-next:
1) Rewrite inner header IPv6 in ICMPv6 messages in ip6t_NPT,
from Michael Zhou.
2) do_ip_vs_set_ctl() dereferences uninitialized value,
from Peilin Ye.
3) Support for userdata in tables, from Jose M. Guisado.
4) Do not increment ct error and invalid stats at the same time,
from Florian Westphal.
5) Remove ct ignore stats, also from Florian.
6) Add ct stats for clash resolution, from Florian Westphal.
7) Bump reference counter bump on ct clash resolution only,
this is safe because bucket lock is held, again from Florian.
8) Use ip_is_fragment() in xt_HMARK, from YueHaibing.
9) Add wildcard support for nft_socket, from Balazs Scheidler.
10) Remove superfluous IPVS dependency on iptables, from
Yaroslav Bolyukin.
11) Remove unused definition in ebt_stp, from Wang Hai.
12) Replace CONFIG_NFT_CHAIN_NAT_{IPV4,IPV6} by CONFIG_NFT_NAT
in selftests/net, from Fabian Frederick.
13) Add userdata support for nft_object, from Jose M. Guisado.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Frontend callback reports EAGAIN to nfnetlink to retry a command, this
is used to signal that module autoloading is required. Unfortunately,
nlmsg_unicast() reports EAGAIN in case the receiver socket buffer gets
full, so it enters a busy-loop.
This patch updates nfnetlink_unicast() to turn EAGAIN into ENOBUFS and
to use nlmsg_unicast(). Remove the flags field in nfnetlink_unicast()
since this is always MSG_DONTWAIT in the existing code which is exactly
what nlmsg_unicast() passes to netlink_unicast() as parameter.
Fixes: 96518518cc ("netfilter: add nftables")
Reported-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
There is a misconception about what "insert_failed" means.
We increment this even when a clash got resolved, so it might not indicate
a problem.
Add a dedicated counter for clash resolution and only increment
insert_failed if a clash cannot be resolved.
For the old /proc interface, export this in place of an older stat
that got removed a while back.
For ctnetlink, export this with a new attribute.
Also correct an outdated comment that implies we add a duplicate tuple --
we only add the (unique) reply direction.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This counter increments when nf_conntrack_in sees a packet that already
has a conntrack attached or when the packet is marked as UNTRACKED.
Neither is an error.
The former is normal for loopback traffic. The second happens for
certain ICMPv6 packets or when nftables/ip(6)tables rules are in place.
In case someone needs to count UNTRACKED packets, or packets
that are marked as untracked before conntrack_in this can be done with
both nftables and ip(6)tables rules.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
If an sctp connection gets re-used, heartbeats are flagged as invalid
because their vtag doesn't match.
Handle this in a similar way as TCP conntrack when it suspects that the
endpoints and conntrack are out-of-sync.
When a HEARTBEAT request fails its vtag validation, flag this in the
conntrack state and accept the packet.
When a HEARTBEAT_ACK is received with an invalid vtag in the reverse
direction after we allowed such a HEARTBEAT through, assume we are
out-of-sync and re-set the vtag info.
v2: remove left-over snippet from an older incarnation that moved
new_state/old_state assignments, thats not needed so keep that
as-is.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pass a sockptr_t to prepare for set_fs-less handling of the kernel
pointer from bpf-cgroup.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Lift the in_compat_syscall() from the callers instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
>> include/linux/netfilter/nf_conntrack_pptp.h:13:20: warning: 'const' type qualifier on return type has no effect [-Wignored-qualifiers]
extern const char *const pptp_msg_name(u_int16_t msg);
^~~~~~
Reported-by: kbuild test robot <lkp@intel.com>
Fixes: 4c559f15ef ("netfilter: nf_conntrack_pptp: prevent buffer overflows in debug code")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
