Currently, CONFIG_JUMP_LABEL just means "I _want_ to use jump label".
The jump label is controlled by HAVE_JUMP_LABEL, which is defined
like this:
#if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL)
# define HAVE_JUMP_LABEL
#endif
We can improve this by testing 'asm goto' support in Kconfig, then
make JUMP_LABEL depend on CC_HAS_ASM_GOTO.
Ugly #ifdef HAVE_JUMP_LABEL will go away, and CONFIG_JUMP_LABEL will
match to the real kernel capability.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
This adds a global netfilter function to extract a conntrack tuple from an
skb. The function uses a new function added to nf_ct_hook, which will try
to get the tuple from skb->_nfct, and do a full lookup if that fails. This
makes it possible to use the lookup function before the skb has passed
through the conntrack init hooks (e.g., in an ingress qdisc). The tuple is
copied to the caller to avoid issues with reference counting.
The function returns false if conntrack is not loaded, allowing it to be
used without incurring a module dependency on conntrack. This is used by
the NAT mode in sch_cake.
Cc: netfilter-devel@vger.kernel.org
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
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 25fd386e0b ("netfilter:
core: add missing __rcu annotation") in your tree and 2c205dd398
("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 25fd386e0b - and remove all code
related to nf_nat_decode_session_hook - which is gone after
2c205dd398, 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>
This reverts commit f92b40a8b2
("netfilter: core: only allow one nat hook per hook point"), this
limitation is no longer needed. The nat core now invokes these
functions and makes sure that hook evaluation stops after a mapping is
created and a null binding is created otherwise.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This will allow the nat core to reuse the nf_hook infrastructure
to maintain nat lookup functions.
The raw versions don't assume a particular hook location, the
functions get added/deleted from the hook blob that is passed to the
functions.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
EEXIST is used for an object that already exists, with the same
name/handle. However, there no same object there, instead there is a
object that is using the single slot that is available for NAT hooks
since patch f92b40a8b2 ("netfilter: core: only allow one nat hook per
hook point"). Let's change this return value before this behaviour gets
exposed in the first -rc.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Fixes the following sparse warning:
net/netfilter/core.c:380:6: warning:
symbol '__nf_unregister_net_hook' was not declared. Should it be static?
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This abstraction has no clients anymore, remove it.
This is what remains from previous authors, so correct copyright
statement after recent modifications and code removal.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Expand NFPROTO_INET in two hook registrations, one for NFPROTO_IPV4 and
another for NFPROTO_IPV6. Hence, we handle NFPROTO_INET from the core.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Instead of passing struct nf_hook_ops, this is needed by follow up
patches to handle NFPROTO_INET from the core.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Just a cleanup, __nf_unregister_net_hook() is used by a follow up patch
when handling NFPROTO_INET as a real family from the core.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The netfilter NAT core cannot deal with more than one NAT hook per hook
location (prerouting, input ...), because the NAT hooks install a NAT null
binding in case the iptables nat table (iptable_nat hooks) or the
corresponding nftables chain (nft nat hooks) doesn't specify a nat
transformation.
Null bindings are needed to detect port collsisions between NAT-ed and
non-NAT-ed connections.
This causes nftables NAT rules to not work when iptable_nat module is
loaded, and vice versa because nat binding has already been attached
when the second nat hook is consulted.
The netfilter core is not really the correct location to handle this
(hooks are just hooks, the core has no notion of what kinds of side
effects a hook implements), but its the only place where we can check
for conflicts between both iptables hooks and nftables hooks without
adding dependencies.
So add nat annotation to hook_ops to describe those hooks that will
add NAT bindings and then make core reject if such a hook already exists.
The annotation fills a padding hole, in case further restrictions appar
we might change this to a 'u8 type' instead of bool.
iptables error if nft nat hook active:
iptables -t nat -A POSTROUTING -j MASQUERADE
iptables v1.4.21: can't initialize iptables table `nat': File exists
Perhaps iptables or your kernel needs to be upgraded.
nftables error if iptables nat table present:
nft -f /etc/nftables/ipv4-nat
/usr/etc/nftables/ipv4-nat:3:1-2: Error: Could not process rule: File exists
table nat {
^^
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
no need to define hook points if the family isn't supported.
Because we need these hooks for either nftables, arp/ebtables
or the 'call-iptables' hack we have in the bridge layer add two
new dependencies, NETFILTER_FAMILY_{ARP,BRIDGE}, and have the
users select them.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
no need to define hook points if the family isn't supported.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Not all families share the same hook count, adjust sizes to what is
needed.
struct net before:
/* size: 6592, cachelines: 103, members: 46 */
after:
/* size: 5952, cachelines: 93, members: 46 */
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
struct net contains:
struct nf_hook_entries __rcu *hooks[NFPROTO_NUMPROTO][NF_MAX_HOOKS];
which store the hook entry point locations for the various protocol
families and the hooks.
Using array results in compact c code when doing accesses, i.e.
x = rcu_dereference(net->nf.hooks[pf][hook]);
but its also wasting a lot of memory, as most families are
not used.
So split the array into those families that are used, which
are only 5 (instead of 13). In most cases, the 'pf' argument is
constant, i.e. gcc removes switch statement.
struct net before:
/* size: 5184, cachelines: 81, members: 46 */
after:
/* size: 4672, cachelines: 73, members: 46 */
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Giuseppe Scrivano says:
"SELinux, if enabled, registers for each new network namespace 6
netfilter hooks."
Cost for this is high. With synchronize_net() removed:
"The net benefit on an SMP machine with two cores is that creating a
new network namespace takes -40% of the original time."
This patch replaces synchronize_net+kvfree with call_rcu().
We store rcu_head at the tail of a structure that has no fixed layout,
i.e. we cannot use offsetof() to compute the start of the original
allocation. Thus store this information right after the rcu head.
We could simplify this by just placing the rcu_head at the start
of struct nf_hook_entries. However, this structure is used in
packet processing hotpath, so only place what is needed for that
at the beginning of the struct.
Reported-by: Giuseppe Scrivano <gscrivan@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
since commit 960632ece6 ("netfilter: convert hook list to an array")
nfqueue no longer stores a pointer to the hook that caused the packet
to be queued. Therefore no extra synchronize_net() call is needed after
dropping the packets enqueued by the old rule blob.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This reverts commit d3ad2c17b4
("netfilter: core: batch nf_unregister_net_hooks synchronize_net calls").
Nothing wrong with it. However, followup patch will delay freeing of hooks
with call_rcu, so all synchronize_net() calls become obsolete and there
is no need anymore for this batching.
This revert causes a temporary performance degradation when destroying
network namespace, but its resolved with the upcoming call_rcu conversion.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
kernel test robot reported:
WARNING: CPU: 0 PID: 1244 at net/netfilter/core.c:218 __nf_hook_entries_try_shrink+0x49/0xcd
[..]
After allowing batching in nf_unregister_net_hooks its possible that an earlier
call to __nf_hook_entries_try_shrink already compacted the list.
If this happens we don't need to do anything.
Fixes: d3ad2c17b4 ("netfilter: core: batch nf_unregister_net_hooks synchronize_net calls")
Reported-by: kernel test robot <xiaolong.ye@intel.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
re-add batching in nf_unregister_net_hooks().
Similar as before, just store an array with to-be-free'd rule arrays
on stack, then call synchronize_net once per batch.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Make sure our grow/shrink routine places them in the correct order.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This converts the storage and layout of netfilter hook entries from a
linked list to an array. After this commit, hook entries will be
stored adjacent in memory. The next pointer is no longer required.
The ops pointers are stored at the end of the array as they are only
used in the register/unregister path and in the legacy br_netfilter code.
nf_unregister_net_hooks() is slower than needed as it just calls
nf_unregister_net_hook in a loop (i.e. at least n synchronize_net()
calls), this will be addressed in followup patch.
Test setup:
- ixgbe 10gbit
- netperf UDP_STREAM, 64 byte packets
- 5 hooks: (raw + mangle prerouting, mangle+filter input, inet filter):
empty mangle and raw prerouting, mangle and filter input hooks:
353.9
this patch:
364.2
Signed-off-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We accidentally return an uninitialized variable.
Fixes: cf56c2f892 ("netfilter: remove old pre-netns era hook api")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
no more users in the tree, remove this.
The old api is racy wrt. module removal, all users have been converted
to the netns-aware api.
The old api pretended we still have global hooks but that has not been
true for a long time.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nf_unregister_net_hook(s) can avoid a second call to synchronize_net,
provided there is no nfqueue active in that net namespace (which is
the common case).
This also gets rid of the extra arg to nf_queue_nf_hook_drop(), normally
this gets called during netns cleanup so no packets should be queued.
For the rare case of base chain being unregistered or module removal
while nfqueue is in use the extra hiccup due to the packet drops isn't
a big deal.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
synchronize_net is expensive and slows down netns cleanup a lot.
We have two APIs to unregister a hook:
nf_unregister_net_hook (which calls synchronize_net())
and
nf_unregister_net_hooks (calls nf_unregister_net_hook in a loop)
Make nf_unregister_net_hook a wapper around new helper
__nf_unregister_net_hook, which unlinks the hook but does not free it.
Then, we can call that helper in nf_unregister_net_hooks and then
call synchronize_net() only once.
Andrey Konovalov reports this change improves syzkaller fuzzing speed at
least twice.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
After this change conntrack operations (lookup, creation, matching from
ruleset) only access one instead of two sk_buff cache lines.
This works for normal conntracks because those are allocated from a slab
that guarantees hw cacheline or 8byte alignment (whatever is larger)
so the 3 bits needed for ctinfo won't overlap with nf_conn addresses.
Template allocation now does manual address alignment (see previous change)
on arches that don't have sufficent kmalloc min alignment.
Some spots intentionally use skb->_nfct instead of skb_nfct() helpers,
this is to avoid undoing the skb_nfct() use when we remove untracked
conntrack object in the future.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This is to facilitate converting from a singly-linked list to an array
of elements.
Signed-off-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
NF_REPEAT is only needed from nf_conntrack_in() under a very specific
case required by the TCP protocol tracker, we can handle this case
without returning to the core hook path. Handling of NF_REPEAT from the
nf_reinject() is left untouched.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nf_iterate() has become rather simple, we can integrate this code into
nf_hook_slow() to reduce the amount of LOC in the core path.
However, we still need nf_iterate() around for nf_queue packet handling,
so move this function there where we only need it. I think it should be
possible to refactor nf_queue code to get rid of it definitely, but
given this is slow path anyway, let's have a look this later.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This field is only useful for nf_queue, so store it in the
nf_queue_entry structure instead, away from the core path. Pass
hook_head to nf_hook_slow().
Since we always have a valid entry on the first iteration in
nf_iterate(), we can use 'do { ... } while (entry)' loop instead.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Use switch() for verdict handling and add explicit handling for
NF_STOLEN and other non-conventional verdicts.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
NF_STOP is only used by br_netfilter these days, and it can be emulated
with a combination of NF_STOLEN plus explicit call to the ->okfn()
function as Florian suggests.
To retain binary compatibility with userspace nf_queue application, we
have to keep NF_STOP around, so libnetfilter_queue userspace userspace
applications still work if they use NF_STOP for some exotic reason.
Out of tree modules using NF_STOP would break, but we don't care about
those.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Patch c5136b15ea ("netfilter: bridge: add and use br_nf_hook_thresh")
introduced br_nf_hook_thresh().
Replace NF_HOOK_THRESH() by br_nf_hook_thresh from
br_nf_forward_finish(), so we have no more callers for this macro.
As a result, state->thresh and explicit thresh parameter in the hook
state structure is not required anymore. And we can get rid of
skip-hook-under-thresh loop in nf_iterate() in the core path that is
only used by br_netfilter to search for the filter hook.
Suggested-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We cannot block/sleep on nf_iterate because netfilter runs under rcu
read lock these days, where blocking is well-known to be illegal. So
let's remove these old comments.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch remove compile time code to catch inconventional verdicts.
We have better ways to handle this case these days, eg. pr_debug() but
even though I don't think this is useful at all, so let's remove this.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nf_queue handling is broken since e3b37f11e6 ("netfilter: replace
list_head with single linked list") for two reasons:
1) If the bypass flag is set on, there are no userspace listeners and
we still have more hook entries to iterate over, then jump to the
next hook. Otherwise accept the packet. On nf_reinject() path, the
okfn() needs to be invoked.
2) We should not re-enter the same hook on packet reinjection. If the
packet is accepted, we have to skip the current hook from where the
packet was enqueued, otherwise the packets gets enqueued over and
over again.
This restores the previous list_for_each_entry_continue() behaviour
happening from nf_iterate() that was dealing with these two cases.
This patch introduces a new nf_queue() wrapper function so this fix
becomes simpler.
Fixes: e3b37f11e6 ("netfilter: replace list_head with single linked list")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Use the correct pattern for singly linked list insertion and
deletion. We can also calculate the list head outside of the
mutex.
Fixes: e3b37f11e6 ("netfilter: replace list_head with single linked list")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/netfilter/core.c | 108 ++++++++++++++++-----------------------------------
1 file changed, 33 insertions(+), 75 deletions(-)
When CONFIG_NETFILTER_INGRESS is unset (or no), we need to handle
the request for registration properly by dropping the hook. This
releases the entry during the set.
Fixes: e3b37f11e6 ("netfilter: replace list_head with single linked list")
Signed-off-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
It's possible for nf_hook_entry_head to return NULL. If two
nf_unregister_net_hook calls happen simultaneously with a single hook
entry in the list, both will enter the nf_hook_mutex critical section.
The first will successfully delete the head, but the second will see
this NULL pointer and attempt to dereference.
This fix ensures that no null pointer dereference could occur when such
a condition happens.
Fixes: e3b37f11e6 ("netfilter: replace list_head with single linked list")
Signed-off-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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 c73c248490 ("netfilter: nf_tables_netdev: remove redundant
ip_hdr assignment") from the net tree and commit ddc8b6027a
("netfilter: introduce nft_set_pktinfo_{ipv4, ipv6}_validate()").
2) Between e8bffe0cf9 ("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 <pablo@netfilter.org>
The netfilter hook list never uses the prev pointer, and so can be trimmed to
be a simple singly-linked list.
In addition to having a more light weight structure for hook traversal,
struct net becomes 5568 bytes (down from 6400) and struct net_device becomes
2176 bytes (down from 2240).
Signed-off-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit adds an upfront check for sane values to be passed when
registering a netfilter hook. This will be used in a future patch for a
simplified hook list traversal.
Signed-off-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
All of the callers of nf_hook_slow already hold the rcu_read_lock, so this
cleanup removes the recursive call. This is just a cleanup, as the locking
code gracefully handles this situation.
Signed-off-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Masahiro Yamada