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Pablo Neira Ayuso says:
====================
Netfilter/IPVS updates for net-next
The following patchset contains Netfilter/IPVS updates for net-next:
1) Add support to specify a stateful expression in set definitions,
this allows users to specify e.g. counters per set elements.
2) Flowtable software counter support.
3) Flowtable hardware offload counter support, from wenxu.
3) Parallelize flowtable hardware offload requests, from Paul Blakey.
This includes a patch to add one work entry per offload command.
4) Several patches to rework nf_queue refcount handling, from Florian
Westphal.
4) A few fixes for the flowtable tunnel offload: Fix crash if tunneling
information is missing and set up indirect flow block as TC_SETUP_FT,
patch from wenxu.
5) Stricter netlink attribute sanity check on filters, from Romain Bellan
and Florent Fourcot.
5) Annotations to make sparse happy, from Jules Irenge.
6) Improve icmp errors in debugging information, from Haishuang Yan.
7) Fix warning in IPVS icmp error debugging, from Haishuang Yan.
8) Fix endianess issue in tcp extension header, from Sergey Marinkevich.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
If outer_proto is not set, GCC warning as following:
In file included from net/netfilter/ipvs/ip_vs_core.c:52:
net/netfilter/ipvs/ip_vs_core.c: In function 'ip_vs_in_icmp':
include/net/ip_vs.h:233:4: warning: 'outer_proto' may be used uninitialized in this function [-Wmaybe-uninitialized]
233 | printk(KERN_DEBUG pr_fmt(msg), ##__VA_ARGS__); \
| ^~~~~~
net/netfilter/ipvs/ip_vs_core.c:1666:8: note: 'outer_proto' was declared here
1666 | char *outer_proto;
| ^~~~~~~~~~~
Fixes: 73348fed35 ("ipvs: optimize tunnel dumps for icmp errors")
Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
I got a problem on MIPS with Big-Endian is turned on: every time when
NF trying to change TCP MSS it returns because of new.v16 was greater
than old.v16. But real MSS was 1460 and my rule was like this:
add rule table chain tcp option maxseg size set 1400
And 1400 is lesser that 1460, not greater.
Later I founded that main causer is cast from u32 to __be16.
Debugging:
In example MSS = 1400(HEX: 0x578). Here is representation of each byte
like it is in memory by addresses from left to right(e.g. [0x0 0x1 0x2
0x3]). LE — Little-Endian system, BE — Big-Endian, left column is type.
LE BE
u32: [78 05 00 00] [00 00 05 78]
As you can see, u32 representation will be casted to u16 from different
half of 4-byte address range. But actually nf_tables uses registers and
store data of various size. Actually TCP MSS stored in 2 bytes. But
registers are still u32 in definition:
struct nft_regs {
union {
u32 data[20];
struct nft_verdict verdict;
};
};
So, access like regs->data[priv->sreg] exactly u32. So, according to
table presents above, per-byte representation of stored TCP MSS in
register will be:
LE BE
(u32)regs->data[]: [78 05 00 00] [05 78 00 00]
^^ ^^
We see that register uses just half of u32 and other 2 bytes may be
used for some another data. But in nft_exthdr_tcp_set_eval() it casted
just like u32 -> __be16:
new.v16 = src
But u32 overfill __be16, so it get 2 low bytes. For clarity draw
one more table(<xx xx> means that bytes will be used for cast).
LE BE
u32: [<78 05> 00 00] [00 00 <05 78>]
(u32)regs->data[]: [<78 05> 00 00] [05 78 <00 00>]
As you can see, for Little-Endian nothing changes, but for Big-endian we
take the wrong half. In my case there is some other data instead of
zeros, so new MSS was wrongly greater.
For shooting this bug I used solution for ports ranges. Applying of this
patch does not affect Little-Endian systems.
Signed-off-by: Sergey Marinkevich <sergey.marinkevich@eltex-co.ru>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Store the conntrack counters to the conntrack entry in the
HW flowtable offload.
Signed-off-by: wenxu <wenxu@ucloud.cn>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add nf_ct_acct_add function to update the conntrack counter
with packets and bytes.
Signed-off-by: wenxu <wenxu@ucloud.cn>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Otherwise, nft_lookup might dereference an uninitialized pointer to the
element extension.
Fixes: 665153ff57 ("netfilter: nf_tables: add bitmap set type")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When CONFIG_NF_CONNTRACK_MARK is not set, any CTA_MARK or CTA_MARK_MASK
in netlink message are not supported. We should return an error when one
of them is set, not both
Fixes: 9306425b70 ("netfilter: ctnetlink: must check mark attributes vs NULL")
Signed-off-by: Romain Bellan <romain.bellan@wifirst.fr>
Signed-off-by: Florent Fourcot <florent.fourcot@wifirst.fr>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Instead of dropping refs+kfree, use the helper added in previous patch.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nf_queue is problematic when another NF_QUEUE invocation happens
from nf_reinject().
1. nf_queue is invoked, increments state->sk refcount.
2. skb is queued, waiting for verdict.
3. sk is closed/released.
3. verdict comes back, nf_reinject is called.
4. nf_reinject drops the reference -- refcount can now drop to 0
Instead of get_ref/release_ref pattern, we need to nest the get_ref calls:
get_ref
get_ref
release_ref
release_ref
So that when we invoke the next processing stage (another netfilter
or the okfn()), we hold at least one reference count on the
devices/socket.
After previous patch, it is now safe to put the entry even after okfn()
has potentially free'd the skb.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The refcount is done via entry->skb, which does work fine.
Major problem: When putting the refcount of the bridge ports, we
must always put the references while the skb is still around.
However, we will need to put the references after okfn() to avoid
a possible 1 -> 0 -> 1 refcount transition, so we cannot use the
skb pointer anymore.
Place the physports in the queue entry structure instead to allow
for refcounting changes in the next patch.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This is a preparation patch, no logical changes.
Move free_entry into core and rename it to something more sensible.
Will ease followup patches which will complicate the refcount handling.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
To allow offload commands to execute in parallel, create workqueue
for flow table offload, and use a work entry per offload command.
Signed-off-by: Paul Blakey <paulb@mellanox.com>
Reviewed-by: Oz Shlomo <ozsh@mellanox.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Currently flow offload threads are synchronized by the flow block mutex.
Use rw lock instead to increase flow insertion (read) concurrency.
Signed-off-by: Paul Blakey <paulb@mellanox.com>
Reviewed-by: Oz Shlomo <ozsh@mellanox.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
It is safe to traverse &net->nft.tables with &net->nft.commit_mutex
held using list_for_each_entry_rcu(). Silence the PROVE_RCU_LIST false
positive,
WARNING: suspicious RCU usage
net/netfilter/nf_tables_api.c:523 RCU-list traversed in non-reader section!!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
1 lock held by iptables/1384:
#0: ffffffff9745c4a8 (&net->nft.commit_mutex){+.+.}, at: nf_tables_valid_genid+0x25/0x60 [nf_tables]
Call Trace:
dump_stack+0xa1/0xea
lockdep_rcu_suspicious+0x103/0x10d
nft_table_lookup.part.0+0x116/0x120 [nf_tables]
nf_tables_newtable+0x12c/0x7d0 [nf_tables]
nfnetlink_rcv_batch+0x559/0x1190 [nfnetlink]
nfnetlink_rcv+0x1da/0x210 [nfnetlink]
netlink_unicast+0x306/0x460
netlink_sendmsg+0x44b/0x770
____sys_sendmsg+0x46b/0x4a0
___sys_sendmsg+0x138/0x1a0
__sys_sendmsg+0xb6/0x130
__x64_sys_sendmsg+0x48/0x50
do_syscall_64+0x69/0xf4
entry_SYSCALL_64_after_hwframe+0x49/0xb3
Signed-off-by: Qian Cai <cai@lca.pw>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The indirect block setup should use TC_SETUP_FT as the type instead of
TC_SETUP_BLOCK. Adjust existing users of the indirect flow block
infrastructure.
Fixes: b5140a36da ("netfilter: flowtable: add indr block setup support")
Signed-off-by: wenxu <wenxu@ucloud.cn>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
After strip GRE/UDP tunnel header for icmp errors, it's better to show
"GRE/UDP" instead of "IPIP" in debug message.
Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Sparse reports a warning at ctnetlink_parse_nat_setup()
warning: context imbalance in ctnetlink_parse_nat_setup()
- unexpected unlock
The root cause is the missing annotation at ctnetlink_parse_nat_setup()
Add the missing __must_hold(RCU) annotation
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Overlapping header include additions in macsec.c
A bug fix in 'net' overlapping with the removal of 'version'
string in ena_netdev.c
Overlapping test additions in selftests Makefile
Overlapping PCI ID table adjustments in iwlwifi driver.
Signed-off-by: David S. Miller <davem@davemloft.net>
net/netfilter/nft_fwd_netdev.c: In function ‘nft_fwd_netdev_eval’:
net/netfilter/nft_fwd_netdev.c:32:10: error: ‘struct sk_buff’ has no member named ‘tc_redirected’
pkt->skb->tc_redirected = 1;
^~
net/netfilter/nft_fwd_netdev.c:33:10: error: ‘struct sk_buff’ has no member named ‘tc_from_ingress’
pkt->skb->tc_from_ingress = 1;
^~
To avoid a direct dependency with tc actions from netfilter, wrap the
redirect bits around CONFIG_NET_REDIRECT and move helpers to
include/linux/skbuff.h. Turn on this toggle from the ifb driver, the
only existing client of these bits in the tree.
This patch adds skb_set_redirected() that sets on the redirected bit
on the skbuff, it specifies if the packet was redirect from ingress
and resets the timestamp (timestamp reset was originally missing in the
netfilter bugfix).
Fixes: bcfabee1af ("netfilter: nft_fwd_netdev: allow to redirect to ifb via ingress")
Reported-by: noreply@ellerman.id.au
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Set skb->tc_redirected to 1, otherwise the ifb driver drops the packet.
Set skb->tc_from_ingress to 1 to reinject the packet back to the ingress
path after leaving the ifb egress path.
This patch inconditionally sets on these two skb fields that are
meaningful to the ifb driver. The existing forward action is guaranteed
to run from ingress path.
Fixes: 39e6dea28a ("netfilter: nf_tables: add forward expression to the netdev family")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Make sure the forward action is only used from ingress.
Fixes: 39e6dea28a ("netfilter: nf_tables: add forward expression to the netdev family")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
...and return -ENOTEMPTY to the front-end in this case, instead of
proceeding. Currently, nft takes care of checking for these cases
and not sending them to the kernel, but if we drop the set_overlap()
call in nft we can end up in situations like:
# nft add table t
# nft add set t s '{ type inet_service ; flags interval ; }'
# nft add element t s '{ 1 - 5 }'
# nft add element t s '{ 6 - 10 }'
# nft add element t s '{ 4 - 7 }'
# nft list set t s
table ip t {
set s {
type inet_service
flags interval
elements = { 1-3, 4-5, 6-7 }
}
}
This change has the primary purpose of making the behaviour
consistent with nft_set_pipapo, but is also functional to avoid
inconsistent behaviour if userspace sends overlapping elements for
any reason.
v2: When we meet the same key data in the tree, as start element while
inserting an end element, or as end element while inserting a start
element, actually check that the existing element is active, before
resetting the overlap flag (Pablo Neira Ayuso)
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Replace negations of nft_rbtree_interval_end() with a new helper,
nft_rbtree_interval_start(), wherever this helps to visualise the
problem at hand, that is, for all the occurrences except for the
comparison against given flags in __nft_rbtree_get().
This gets especially useful in the next patch.
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
...and return -ENOTEMPTY to the front-end on collision, -EEXIST if
an identical element already exists. Together with the previous patch,
element collision will now be returned to the user as -EEXIST.
Reported-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Currently, the -EEXIST return code of ->insert() callbacks is ambiguous: it
might indicate that a given element (including intervals) already exists as
such, or that the new element would clash with existing ones.
If identical elements already exist, the front-end is ignoring this without
returning error, in case NLM_F_EXCL is not set. However, if the new element
can't be inserted due an overlap, we should report this to the user.
To this purpose, allow set back-ends to return -ENOTEMPTY on collision with
existing elements, translate that to -EEXIST, and return that to userspace,
no matter if NLM_F_EXCL was set.
Reported-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nf_flow_rule_match() sets control.addr_type in key, so needs to also set
the corresponding mask. An exact match is wanted, so mask is all ones.
Fixes: c29f74e0df ("netfilter: nf_flow_table: hardware offload support")
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The tc ct action does not cache the route in the flowtable entry.
Fixes: 88bf6e4114 ("netfilter: flowtable: add tunnel encap/decap action offload support")
Fixes: cfab6dbd0e ("netfilter: flowtable: add tunnel match offload support")
Signed-off-by: wenxu <wenxu@ucloud.cn>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Freeing a flowtable with offloaded flows, the flow are deleted from
hardware but are not deleted from the flow table, leaking them,
and leaving their offload bit on.
Add a second pass of the disabled gc to delete the these flows from
the flow table before freeing it.
Fixes: c29f74e0df ("netfilter: nf_flow_table: hardware offload support")
Signed-off-by: Paul Blakey <paulb@mellanox.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Since pskb_may_pull may change skb->data, so we need to reload ip{v6}h at
the right place.
Fixes: a908fdec3d ("netfilter: nf_flow_table: move ipv6 offload hook code to nf_flow_table")
Fixes: 7d20868717 ("netfilter: nf_flow_table: move ipv4 offload hook code to nf_flow_table")
Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Since nf_flow_snat_port and nf_flow_snat_ip{v6} call pskb_may_pull()
which may change skb->data, so we need to reload ip{v6}h at the right
place.
Fixes: a908fdec3d ("netfilter: nf_flow_table: move ipv6 offload hook code to nf_flow_table")
Fixes: 7d20868717 ("netfilter: nf_flow_table: move ipv4 offload hook code to nf_flow_table")
Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch adds nft_set_elem_expr_destroy() to destroy stateful
expressions in set elements.
This patch also updates the commit path to call this function to invoke
expr->ops->destroy_clone when required.
This is implicitly fixing up a module reference counter leak and
a memory leak in expressions that allocated internal state, e.g.
nft_counter.
Fixes: 4094445229 ("netfilter: nf_tables: add elements with stateful expressions")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
After copying the expression to the set element extension, release the
expression and reset the pointer to avoid a double-free from the error
path.
Fixes: 4094445229 ("netfilter: nf_tables: add elements with stateful expressions")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch allows users to specify the stateful expression for the
elements in this set via NFTA_SET_EXPR. This new feature allows you to
turn on counters for all of the elements in this set.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This reverts the following commits:
8537f78647 ("netfilter: Introduce egress hook")
5418d3881e ("netfilter: Generalize ingress hook")
b030f194ae ("netfilter: Rename ingress hook include file")
>From the discussion in [0], the author's main motivation to add a hook
in fast path is for an out of tree kernel module, which is a red flag
to begin with. Other mentioned potential use cases like NAT{64,46}
is on future extensions w/o concrete code in the tree yet. Revert as
suggested [1] given the weak justification to add more hooks to critical
fast-path.
[0] https://lore.kernel.org/netdev/cover.1583927267.git.lukas@wunner.de/
[1] https://lore.kernel.org/netdev/20200318.011152.72770718915606186.davem@davemloft.net/
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Miller <davem@davemloft.net>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Nacked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit e687ad60af ("netfilter: add netfilter ingress hook after
handle_ing() under unique static key") introduced the ability to
classify packets on ingress.
Allow the same on egress. Position the hook immediately before a packet
is handed to tc and then sent out on an interface, thereby mirroring the
ingress order. This order allows marking packets in the netfilter
egress hook and subsequently using the mark in tc. Another benefit of
this order is consistency with a lot of existing documentation which
says that egress tc is performed after netfilter hooks.
Egress hooks already exist for the most common protocols, such as
NF_INET_LOCAL_OUT or NF_ARP_OUT, and those are to be preferred because
they are executed earlier during packet processing. However for more
exotic protocols, there is currently no provision to apply netfilter on
egress. A common workaround is to enslave the interface to a bridge and
use ebtables, or to resort to tc. But when the ingress hook was
introduced, consensus was that users should be given the choice to use
netfilter or tc, whichever tool suits their needs best:
https://lore.kernel.org/netdev/20150430153317.GA3230@salvia/
This hook is also useful for NAT46/NAT64, tunneling and filtering of
locally generated af_packet traffic such as dhclient.
There have also been occasional user requests for a netfilter egress
hook in the past, e.g.:
https://www.spinics.net/lists/netfilter/msg50038.html
Performance measurements with pktgen surprisingly show a speedup rather
than a slowdown with this commit:
* Without this commit:
Result: OK: 34240933(c34238375+d2558) usec, 100000000 (60byte,0frags)
2920481pps 1401Mb/sec (1401830880bps) errors: 0
* With this commit:
Result: OK: 33997299(c33994193+d3106) usec, 100000000 (60byte,0frags)
2941410pps 1411Mb/sec (1411876800bps) errors: 0
* Without this commit + tc egress:
Result: OK: 39022386(c39019547+d2839) usec, 100000000 (60byte,0frags)
2562631pps 1230Mb/sec (1230062880bps) errors: 0
* With this commit + tc egress:
Result: OK: 37604447(c37601877+d2570) usec, 100000000 (60byte,0frags)
2659259pps 1276Mb/sec (1276444320bps) errors: 0
* With this commit + nft egress:
Result: OK: 41436689(c41434088+d2600) usec, 100000000 (60byte,0frags)
2413320pps 1158Mb/sec (1158393600bps) errors: 0
Tested on a bare-metal Core i7-3615QM, each measurement was performed
three times to verify that the numbers are stable.
Commands to perform a measurement:
modprobe pktgen
echo "add_device lo@3" > /proc/net/pktgen/kpktgend_3
samples/pktgen/pktgen_bench_xmit_mode_queue_xmit.sh -i 'lo@3' -n 100000000
Commands for testing tc egress:
tc qdisc add dev lo clsact
tc filter add dev lo egress protocol ip prio 1 u32 match ip dst 4.3.2.1/32
Commands for testing nft egress:
nft add table netdev t
nft add chain netdev t co \{ type filter hook egress device lo priority 0 \; \}
nft add rule netdev t co ip daddr 4.3.2.1/32 drop
All testing was performed on the loopback interface to avoid distorting
measurements by the packet handling in the low-level Ethernet driver.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
since commit b884fa4617 ("netfilter: conntrack: unify sysctl handling")
conntrack no longer exposes most of its sysctls (e.g. tcp timeouts
settings) to network namespaces that are not owned by the initial user
namespace.
This patch exposes all sysctls even if the namespace is unpriviliged.
compared to a 4.19 kernel, the newly visible and writeable sysctls are:
net.netfilter.nf_conntrack_acct
net.netfilter.nf_conntrack_timestamp
.. to allow to enable accouting and timestamp extensions.
net.netfilter.nf_conntrack_events
.. to turn off conntrack event notifications.
net.netfilter.nf_conntrack_checksum
.. to disable checksum validation.
net.netfilter.nf_conntrack_log_invalid
.. to enable logging of packets deemed invalid by conntrack.
newly visible sysctls that are only exported as read-only:
net.netfilter.nf_conntrack_count
.. current number of conntrack entries living in this netns.
net.netfilter.nf_conntrack_max
.. global upperlimit (maximum size of the table).
net.netfilter.nf_conntrack_buckets
.. size of the conntrack table (hash buckets).
net.netfilter.nf_conntrack_expect_max
.. maximum number of permitted expectations in this netns.
net.netfilter.nf_conntrack_helper
.. conntrack helper auto assignment.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Update nft_add_set_elem() to handle the NFTA_SET_ELEM_EXPR netlink
attribute. This patch allows users to to add elements with stateful
expressions.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
