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Author SHA1 Message Date
Vlad Buslov
9bc64bd0cd net/sched: act_ct: Always fill offloading tuple iifidx
Referenced commit doesn't always set iifidx when offloading the flow to
hardware. Fix the following cases:

- nf_conn_act_ct_ext_fill() is called before extension is created with
nf_conn_act_ct_ext_add() in tcf_ct_act(). This can cause rule offload with
unspecified iifidx when connection is offloaded after only single
original-direction packet has been processed by tc data path. Always fill
the new nf_conn_act_ct_ext instance after creating it in
nf_conn_act_ct_ext_add().

- Offloading of unidirectional UDP NEW connections is now supported, but ct
flow iifidx field is not updated when connection is promoted to
bidirectional which can result reply-direction iifidx to be zero when
refreshing the connection. Fill in the extension and update flow iifidx
before calling flow_offload_refresh().

Fixes: 9795ded7f9 ("net/sched: act_ct: Fill offloading tuple iifidx")
Reviewed-by: Paul Blakey <paulb@nvidia.com>
Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Fixes: 6a9bad0069 ("net/sched: act_ct: offload UDP NEW connections")
Link: https://lore.kernel.org/r/20231103151410.764271-1-vladbu@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-11-08 17:47:08 -08:00
Jakub Kicinski
ec4c20ca09 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

Conflicts:

net/mac80211/rx.c
  91535613b6 ("wifi: mac80211: don't drop all unprotected public action frames")
  6c02fab724 ("wifi: mac80211: split ieee80211_drop_unencrypted_mgmt() return value")

Adjacent changes:

drivers/net/ethernet/apm/xgene/xgene_enet_main.c
  61471264c0 ("net: ethernet: apm: Convert to platform remove callback returning void")
  d2ca43f306 ("net: xgene: Fix unused xgene_enet_of_match warning for !CONFIG_OF")

net/vmw_vsock/virtio_transport.c
  64c99d2d6a ("vsock/virtio: support to send non-linear skb")
  53b08c4985 ("vsock/virtio: initialize the_virtio_vsock before using VQs")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-10-26 13:46:28 -07:00
Pablo Neira Ayuso
735795f68b netfilter: flowtable: GC pushes back packets to classic path
Since 41f2c7c342 ("net/sched: act_ct: Fix promotion of offloaded
unreplied tuple"), flowtable GC pushes back flows with IPS_SEEN_REPLY
back to classic path in every run, ie. every second. This is because of
a new check for NF_FLOW_HW_ESTABLISHED which is specific of sched/act_ct.

In Netfilter's flowtable case, NF_FLOW_HW_ESTABLISHED never gets set on
and IPS_SEEN_REPLY is unreliable since users decide when to offload the
flow before, such bit might be set on at a later stage.

Fix it by adding a custom .gc handler that sched/act_ct can use to
deal with its NF_FLOW_HW_ESTABLISHED bit.

Fixes: 41f2c7c342 ("net/sched: act_ct: Fix promotion of offloaded unreplied tuple")
Reported-by: Vladimir Smelhaus <vl.sm@email.cz>
Reviewed-by: Paul Blakey <paulb@nvidia.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-10-25 11:35:46 +02:00
Pablo Neira Ayuso
078996fcd6 netfilter: nf_tables: set->ops->insert returns opaque set element in case of EEXIST
Return struct nft_elem_priv instead of struct nft_set_ext for
consistency with ("netfilter: nf_tables: expose opaque set element as
struct nft_elem_priv") and to prepare the introduction of element
timeout updates from control path.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-10-24 13:37:46 +02:00
Pablo Neira Ayuso
0e1ea651c9 netfilter: nf_tables: shrink memory consumption of set elements
Instead of copying struct nft_set_elem into struct nft_trans_elem, store
the pointer to the opaque set element object in the transaction. Adapt
set backend API (and set backend implementations) to take the pointer to
opaque set element representation whenever required.

This patch deconstifies .remove() and .activate() set backend API since
these modify the set element opaque object. And it also constify
nft_set_elem_ext() this provides access to the nft_set_ext struct
without updating the object.

According to pahole on x86_64, this patch shrinks struct nft_trans_elem
size from 216 to 24 bytes.

This patch also reduces stack memory consumption by removing the
template struct nft_set_elem object, using the opaque set element object
instead such as from the set iterator API, catchall elements and the get
element command.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-10-24 13:37:42 +02:00
Pablo Neira Ayuso
9dad402b89 netfilter: nf_tables: expose opaque set element as struct nft_elem_priv
Add placeholder structure and place it at the beginning of each struct
nft_*_elem for each existing set backend, instead of exposing elements
as void type to the frontend which defeats compiler type checks. Use
this pointer to this new type to replace void *.

This patch updates the following set backend API to use this new struct
nft_elem_priv placeholder structure:

- update
- deactivate
- flush
- get

as well as the following helper functions:

- nft_set_elem_ext()
- nft_set_elem_init()
- nft_set_elem_destroy()
- nf_tables_set_elem_destroy()

This patch adds nft_elem_priv_cast() to cast struct nft_elem_priv to
native element representation from the corresponding set backend.
BUILD_BUG_ON() makes sure this .priv placeholder is always at the top
of the opaque set element representation.

Suggested-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-10-24 13:16:30 +02:00
Pablo Neira Ayuso
6509a2e410 netfilter: nf_tables: set backend .flush always succeeds
.flush is always successful since this results from iterating over the
set elements to toggle mark the element as inactive in the next
generation.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-10-24 13:16:30 +02:00
Florian Westphal
643d126036 netfilter: conntrack: switch connlabels to atomic_t
The spinlock is back from the day when connabels did not have
a fixed size and reallocation had to be supported.

Remove it.  This change also allows to call the helpers from
softirq or timers without deadlocks.

Also add WARN()s to catch refcounting imbalances.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-10-24 13:16:30 +02:00
Florian Westphal
2560016721 netfilter: nf_tables: de-constify set commit ops function argument
The set backend using this already has to work around this via ugly
cast, don't spread this pattern.

Signed-off-by: Florian Westphal <fw@strlen.de>
2023-10-18 10:26:43 +02:00
George Guo
94ecde833b netfilter: cleanup struct nft_table
Add comments for nlpid, family, udlen and udata in struct nft_table, and
afinfo is no longer a member of struct nft_table, so remove the comment
for it.

Signed-off-by: George Guo <guodongtai@kylinos.cn>
Signed-off-by: Florian Westphal <fw@strlen.de>
2023-10-10 16:34:28 +02:00
Florian Westphal
8a23f4ab92 netfilter: conntrack: simplify nf_conntrack_alter_reply
nf_conntrack_alter_reply doesn't do helper reassignment anymore.
Remove the comments that make this claim.

Furthermore, remove dead code from the function and place ot
in nf_conntrack.h.

Signed-off-by: Florian Westphal <fw@strlen.de>
2023-10-10 16:34:28 +02:00
Florian Westphal
cf5000a778 netfilter: nf_tables: fix memleak when more than 255 elements expired
When more than 255 elements expired we're supposed to switch to a new gc
container structure.

This never happens: u8 type will wrap before reaching the boundary
and nft_trans_gc_space() always returns true.

This means we recycle the initial gc container structure and
lose track of the elements that came before.

While at it, don't deref 'gc' after we've passed it to call_rcu.

Fixes: 5f68718b34 ("netfilter: nf_tables: GC transaction API to avoid race with control plane")
Reported-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
2023-09-20 10:35:23 +02:00
Pablo Neira Ayuso
4a9e12ea7e netfilter: nft_set_pipapo: call nft_trans_gc_queue_sync() in catchall GC
pipapo needs to enqueue GC transactions for catchall elements through
nft_trans_gc_queue_sync(). Add nft_trans_gc_catchall_sync() and
nft_trans_gc_catchall_async() to handle GC transaction queueing
accordingly.

Fixes: 5f68718b34 ("netfilter: nf_tables: GC transaction API to avoid race with control plane")
Fixes: f6c383b8c3 ("netfilter: nf_tables: adapt set backend to use GC transaction API")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-09-08 03:26:57 +02:00
Jakub Kicinski
57ce6427e0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

Conflicts:

include/net/inet_sock.h
  f866fbc842 ("ipv4: fix data-races around inet->inet_id")
  c274af2242 ("inet: introduce inet->inet_flags")
https://lore.kernel.org/all/679ddff6-db6e-4ff6-b177-574e90d0103d@tessares.net/

Adjacent changes:

drivers/net/bonding/bond_alb.c
  e74216b8de ("bonding: fix macvlan over alb bond support")
  f11e5bd159 ("bonding: support balance-alb with openvswitch")

drivers/net/ethernet/broadcom/bgmac.c
  d6499f0b7c ("net: bgmac: Return PTR_ERR() for fixed_phy_register()")
  23a14488ea ("net: bgmac: Fix return value check for fixed_phy_register()")

drivers/net/ethernet/broadcom/genet/bcmmii.c
  32bbe64a13 ("net: bcmgenet: Fix return value check for fixed_phy_register()")
  acf50d1adb ("net: bcmgenet: Return PTR_ERR() for fixed_phy_register()")

net/sctp/socket.c
  f866fbc842 ("ipv4: fix data-races around inet->inet_id")
  b09bde5c35 ("inet: move inet->mc_loop to inet->inet_frags")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-24 10:51:39 -07:00
Florian Westphal
8e51830e29 netfilter: nf_tables: defer gc run if previous batch is still pending
Don't queue more gc work, else we may queue the same elements multiple
times.

If an element is flagged as dead, this can mean that either the previous
gc request was invalidated/discarded by a transaction or that the previous
request is still pending in the system work queue.

The latter will happen if the gc interval is set to a very low value,
e.g. 1ms, and system work queue is backlogged.

The sets refcount is 1 if no previous gc requeusts are queued, so add
a helper for this and skip gc run if old requests are pending.

Add a helper for this and skip the gc run in this case.

Fixes: f6c383b8c3 ("netfilter: nf_tables: adapt set backend to use GC transaction API")
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-08-23 16:12:59 +02:00
Florian Westphal
4b80ced971 netfilter: nf_tables: validate all pending tables
We have to validate all tables in the transaction that are in
VALIDATE_DO state, the blamed commit below did not move the break
statement to its right location so we only validate one table.

Moreover, we can't init table->validate to _SKIP when a table object
is allocated.

If we do, then if a transcaction creates a new table and then
fails the transaction, nfnetlink will loop and nft will hang until
user cancels the command.

Add back the pernet state as a place to stash the last state encountered.
This is either _DO (we hit an error during commit validation) or _SKIP
(transaction passed all checks).

Fixes: 00c320f9b7 ("netfilter: nf_tables: make validation state per table")
Reported-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
2023-08-23 16:10:01 +02:00
Jakub Kicinski
7ff57803d2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

Conflicts:

drivers/net/ethernet/sfc/tc.c
  fa165e1949 ("sfc: don't unregister flow_indr if it was never registered")
  3bf969e88a ("sfc: add MAE table machinery for conntrack table")
https://lore.kernel.org/all/20230818112159.7430e9b4@canb.auug.org.au/

No adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-18 12:44:56 -07:00
Florian Westphal
08713cb006 netfilter: nf_tables: fix kdoc warnings after gc rework
Jakub Kicinski says:
  We've got some new kdoc warnings here:
  net/netfilter/nft_set_pipapo.c:1557: warning: Function parameter or member '_set' not described in 'pipapo_gc'
  net/netfilter/nft_set_pipapo.c:1557: warning: Excess function parameter 'set' description in 'pipapo_gc'
  include/net/netfilter/nf_tables.h:577: warning: Function parameter or member 'dead' not described in 'nft_set'

Fixes: 5f68718b34 ("netfilter: nf_tables: GC transaction API to avoid race with control plane")
Fixes: f6c383b8c3 ("netfilter: nf_tables: adapt set backend to use GC transaction API")
Reported-by: Jakub Kicinski <kuba@kernel.org>
Closes: https://lore.kernel.org/netdev/20230810104638.746e46f1@kernel.org/
Signed-off-by: Florian Westphal <fw@strlen.de>
2023-08-16 00:05:14 +02:00
Jakub Kicinski
4d016ae42e Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

No conflicts.

Adjacent changes:

drivers/net/ethernet/intel/igc/igc_main.c
  06b412589e ("igc: Add lock to safeguard global Qbv variables")
  d3750076d4 ("igc: Add TransmissionOverrun counter")

drivers/net/ethernet/microsoft/mana/mana_en.c
  a7dfeda6fd ("net: mana: Fix MANA VF unload when hardware is unresponsive")
  a9ca9f9cef ("page_pool: split types and declarations from page_pool.h")
  92272ec410 ("eth: add missing xdp.h includes in drivers")

net/mptcp/protocol.h
  511b90e392 ("mptcp: fix disconnect vs accept race")
  b8dc6d6ce9 ("mptcp: fix rcv buffer auto-tuning")

tools/testing/selftests/net/mptcp/mptcp_join.sh
  c8c101ae39 ("selftests: mptcp: join: fix 'implicit EP' test")
  03668c65d1 ("selftests: mptcp: join: rework detailed report")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-08-10 14:10:53 -07:00
Pablo Neira Ayuso
a2dd0233cb netfilter: nf_tables: remove busy mark and gc batch API
Ditch it, it has been replace it by the GC transaction API and it has no
clients anymore.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-08-10 08:25:27 +02:00
Pablo Neira Ayuso
5f68718b34 netfilter: nf_tables: GC transaction API to avoid race with control plane
The set types rhashtable and rbtree use a GC worker to reclaim memory.
From system work queue, in periodic intervals, a scan of the table is
done.

The major caveat here is that the nft transaction mutex is not held.
This causes a race between control plane and GC when they attempt to
delete the same element.

We cannot grab the netlink mutex from the work queue, because the
control plane has to wait for the GC work queue in case the set is to be
removed, so we get following deadlock:

   cpu 1                                cpu2
     GC work                            transaction comes in , lock nft mutex
       `acquire nft mutex // BLOCKS
                                        transaction asks to remove the set
                                        set destruction calls cancel_work_sync()

cancel_work_sync will now block forever, because it is waiting for the
mutex the caller already owns.

This patch adds a new API that deals with garbage collection in two
steps:

1) Lockless GC of expired elements sets on the NFT_SET_ELEM_DEAD_BIT
   so they are not visible via lookup. Annotate current GC sequence in
   the GC transaction. Enqueue GC transaction work as soon as it is
   full. If ruleset is updated, then GC transaction is aborted and
   retried later.

2) GC work grabs the mutex. If GC sequence has changed then this GC
   transaction lost race with control plane, abort it as it contains
   stale references to objects and let GC try again later. If the
   ruleset is intact, then this GC transaction deactivates and removes
   the elements and it uses call_rcu() to destroy elements.

Note that no elements are removed from GC lockless path, the _DEAD bit
is set and pointers are collected. GC catchall does not remove the
elements anymore too. There is a new set->dead flag that is set on to
abort the GC transaction to deal with set->ops->destroy() path which
removes the remaining elements in the set from commit_release, where no
mutex is held.

To deal with GC when mutex is held, which allows safe deactivate and
removal, add sync GC API which releases the set element object via
call_rcu(). This is used by rbtree and pipapo backends which also
perform garbage collection from control plane path.

Since element removal from sets can happen from control plane and
element garbage collection/timeout, it is necessary to keep the set
structure alive until all elements have been deactivated and destroyed.

We cannot do a cancel_work_sync or flush_work in nft_set_destroy because
its called with the transaction mutex held, but the aforementioned async
work queue might be blocked on the very mutex that nft_set_destroy()
callchain is sitting on.

This gives us the choice of ABBA deadlock or UaF.

To avoid both, add set->refs refcount_t member. The GC API can then
increment the set refcount and release it once the elements have been
free'd.

Set backends are adapted to use the GC transaction API in a follow up
patch entitled:

  ("netfilter: nf_tables: use gc transaction API in set backends")

This is joint work with Florian Westphal.

Fixes: cfed7e1b1f ("netfilter: nf_tables: add set garbage collection helpers")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-08-10 08:25:16 +02:00
Yue Haibing
172af3eab0 netfilter: conntrack: Remove unused function declarations
Commit 1015c3de23 ("netfilter: conntrack: remove extension register api")
leave nf_conntrack_acct_fini() and nf_conntrack_labels_init() unused, remove it.
And commit a0ae2562c6 ("netfilter: conntrack: remove l3proto abstraction")
leave behind nf_ct_l3proto_try_module_get() and nf_ct_l3proto_module_put().

Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
2023-08-08 13:02:00 +02:00
Yue Haibing
529f63fa11 netfilter: helper: Remove unused function declarations
Commit b118509076 ("netfilter: remove nf_conntrack_helper sysctl and modparam toggles")
leave these unused declarations.

Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
2023-08-08 13:01:59 +02:00
Xin Long
4914109a8e netfilter: allow exp not to be removed in nf_ct_find_expectation
Currently nf_conntrack_in() calling nf_ct_find_expectation() will
remove the exp from the hash table. However, in some scenario, we
expect the exp not to be removed when the created ct will not be
confirmed, like in OVS and TC conntrack in the following patches.

This patch allows exp not to be removed by setting IPS_CONFIRMED
in the status of the tmpl.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Aaron Conole <aconole@redhat.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-07-20 10:06:36 +02:00
Florian Westphal
eaf9e7192e netfilter: conntrack: don't fold port numbers into addresses before hashing
Originally this used jhash2() over tuple and folded the zone id,
the pernet hash value, destination port and l4 protocol number into the
32bit seed value.

When the switch to siphash was done, I used an on-stack temporary
buffer to build a suitable key to be hashed via siphash().

But this showed up as performance regression, so I got rid of
the temporary copy and collected to-be-hashed data in 4 u64 variables.

This makes it easy to build tuples that produce the same hash, which isn't
desirable even though chain lengths are limited.

Switch back to plain siphash, but just like with jhash2(), take advantage
of the fact that most of to-be-hashed data is already in a suitable order.

Use an empty struct as annotation in 'struct nf_conntrack_tuple' to mark
last member that can be used as hash input.

The only remaining data that isn't present in the tuple structure are the
zone identifier and the pernet hash: fold those into the key.

Fixes: d2c806abcf ("netfilter: conntrack: use siphash_4u64")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-07-05 14:42:16 +02:00
Pablo Neira Ayuso
1689f25924 netfilter: nf_tables: report use refcount overflow
Overflow use refcount checks are not complete.

Add helper function to deal with object reference counter tracking.
Report -EMFILE in case UINT_MAX is reached.

nft_use_dec() splats in case that reference counter underflows,
which should not ever happen.

Add nft_use_inc_restore() and nft_use_dec_restore() which are used
to restore reference counter from error and abort paths.

Use u32 in nft_flowtable and nft_object since helper functions cannot
work on bitfields.

Remove the few early incomplete checks now that the helper functions
are in place and used to check for refcount overflow.

Fixes: 96518518cc ("netfilter: add nftables")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-07-05 14:42:15 +02:00
Jakub Kicinski
61dc651cdf netfilter pull request 23-06-26
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Merge tag 'nf-next-23-06-26' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next

Pablo Neira Ayuso says:

====================
Netfilter/IPVS updates for net-next

1) Allow slightly larger IPVS connection table size from Kconfig for
   64-bit arch, from Abhijeet Rastogi.

2) Since IPVS connection table might be larger than 2^20 after previous
   patch, allow to limit it depending on the available memory.
   Moreover, use kvmalloc. From Julian Anastasov.

3) Do not rebuild VLAN header in nft_payload when matching source and
   destination MAC address.

4) Remove nested rcu read lock side in ip_set_test(), from Florian Westphal.

5) Allow to update set size, also from Florian.

6) Improve NAT tuple selection when connection is closing,
   from Florian Westphal.

7) Support for resetting set element stateful expression, from Phil Sutter.

8) Use NLA_POLICY_MAX to narrow down maximum attribute value in nf_tables,
   from Florian Westphal.

* tag 'nf-next-23-06-26' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next:
  netfilter: nf_tables: limit allowed range via nla_policy
  netfilter: nf_tables: Introduce NFT_MSG_GETSETELEM_RESET
  netfilter: snat: evict closing tcp entries on reply tuple collision
  netfilter: nf_tables: permit update of set size
  netfilter: ipset: remove rcu_read_lock_bh pair from ip_set_test
  netfilter: nft_payload: rebuild vlan header when needed
  ipvs: dynamically limit the connection hash table
  ipvs: increase ip_vs_conn_tab_bits range for 64BIT
====================

Link: https://lore.kernel.org/r/20230626064749.75525-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-26 12:59:18 -07:00
Florian Westphal
96b2ef9b16 netfilter: nf_tables: permit update of set size
Now that set->nelems is always updated permit update of the sets max size.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-06-26 08:05:57 +02:00
Jakub Kicinski
a7384f3918 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

Conflicts:

tools/testing/selftests/net/fcnal-test.sh
  d7a2fc1437 ("selftests: net: fcnal-test: check if FIPS mode is enabled")
  dd017c72dd ("selftests: fcnal: Test SO_DONTROUTE on TCP sockets.")
https://lore.kernel.org/all/5007b52c-dd16-dbf6-8d64-b9701bfa498b@tessares.net/
https://lore.kernel.org/all/20230619105427.4a0df9b3@canb.auug.org.au/

No adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-22 18:40:38 -07:00
Pablo Neira Ayuso
938154b93b netfilter: nf_tables: reject unbound anonymous set before commit phase
Add a new list to track set transaction and to check for unbound
anonymous sets before entering the commit phase.

Bail out at the end of the transaction handling if an anonymous set
remains unbound.

Fixes: 96518518cc ("netfilter: add nftables")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-06-20 22:43:41 +02:00
Pablo Neira Ayuso
628bd3e49c netfilter: nf_tables: drop map element references from preparation phase
set .destroy callback releases the references to other objects in maps.
This is very late and it results in spurious EBUSY errors. Drop refcount
from the preparation phase instead, update set backend not to drop
reference counter from set .destroy path.

Exceptions: NFT_TRANS_PREPARE_ERROR does not require to drop the
reference counter because the transaction abort path releases the map
references for each element since the set is unbound. The abort path
also deals with releasing reference counter for new elements added to
unbound sets.

Fixes: 591054469b ("netfilter: nf_tables: revisit chain/object refcounting from elements")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-06-20 22:43:40 +02:00
Pablo Neira Ayuso
26b5a5712e netfilter: nf_tables: add NFT_TRANS_PREPARE_ERROR to deal with bound set/chain
Add a new state to deal with rule expressions deactivation from the
newrule error path, otherwise the anonymous set remains in the list in
inactive state for the next generation. Mark the set/chain transaction
as unbound so the abort path releases this object, set it as inactive in
the next generation so it is not reachable anymore from this transaction
and reference counter is dropped.

Fixes: 1240eb93f0 ("netfilter: nf_tables: incorrect error path handling with NFT_MSG_NEWRULE")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-06-20 22:43:40 +02:00
Pablo Neira Ayuso
4bedf9eee0 netfilter: nf_tables: fix chain binding transaction logic
Add bound flag to rule and chain transactions as in 6a0a8d10a3
("netfilter: nf_tables: use-after-free in failing rule with bound set")
to skip them in case that the chain is already bound from the abort
path.

This patch fixes an imbalance in the chain use refcnt that triggers a
WARN_ON on the table and chain destroy path.

This patch also disallows nested chain bindings, which is not
supported from userspace.

The logic to deal with chain binding in nft_data_hold() and
nft_data_release() is not correct. The NFT_TRANS_PREPARE state needs a
special handling in case a chain is bound but next expressions in the
same rule fail to initialize as described by 1240eb93f0 ("netfilter:
nf_tables: incorrect error path handling with NFT_MSG_NEWRULE").

The chain is left bound if rule construction fails, so the objects
stored in this chain (and the chain itself) are released by the
transaction records from the abort path, follow up patch ("netfilter:
nf_tables: add NFT_TRANS_PREPARE_ERROR to deal with bound set/chain")
completes this error handling.

When deleting an existing rule, chain bound flag is set off so the
rule expression .destroy path releases the objects.

Fixes: d0e2c7de92 ("netfilter: nf_tables: add NFT_CHAIN_BINDING")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-06-20 22:41:51 +02:00
Jakub Kicinski
173780ff18 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

Conflicts:

include/linux/mlx5/driver.h
  617f5db1a6 ("RDMA/mlx5: Fix affinity assignment")
  dc13180824 ("net/mlx5: Enable devlink port for embedded cpu VF vports")
https://lore.kernel.org/all/20230613125939.595e50b8@canb.auug.org.au/

tools/testing/selftests/net/mptcp/mptcp_join.sh
  47867f0a7e ("selftests: mptcp: join: skip check if MIB counter not supported")
  425ba80312 ("selftests: mptcp: join: support RM_ADDR for used endpoints or not")
  45b1a1227a ("mptcp: introduces more address related mibs")
  0639fa230a ("selftests: mptcp: add explicit check for new mibs")
https://lore.kernel.org/netdev/20230609-upstream-net-20230610-mptcp-selftests-support-old-kernels-part-3-v1-0-2896fe2ee8a3@tessares.net/

No adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-15 22:19:41 -07:00
Paul Blakey
41f2c7c342 net/sched: act_ct: Fix promotion of offloaded unreplied tuple
Currently UNREPLIED and UNASSURED connections are added to the nf flow
table. This causes the following connection packets to be processed
by the flow table which then skips conntrack_in(), and thus such the
connections will remain UNREPLIED and UNASSURED even if reply traffic
is then seen. Even still, the unoffloaded reply packets are the ones
triggering hardware update from new to established state, and if
there aren't any to triger an update and/or previous update was
missed, hardware can get out of sync with sw and still mark
packets as new.

Fix the above by:
1) Not skipping conntrack_in() for UNASSURED packets, but still
   refresh for hardware, as before the cited patch.
2) Try and force a refresh by reply-direction packets that update
   the hardware rules from new to established state.
3) Remove any bidirectional flows that didn't failed to update in
   hardware for re-insertion as bidrectional once any new packet
   arrives.

Fixes: 6a9bad0069 ("net/sched: act_ct: offload UDP NEW connections")
Co-developed-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: Paul Blakey <paulb@nvidia.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Link: https://lore.kernel.org/r/1686313379-117663-1-git-send-email-paulb@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-06-14 09:56:50 +02:00
Pablo Neira Ayuso
212ed75dc5 netfilter: nf_tables: integrate pipapo into commit protocol
The pipapo set backend follows copy-on-update approach, maintaining one
clone of the existing datastructure that is being updated. The clone
and current datastructures are swapped via rcu from the commit step.

The existing integration with the commit protocol is flawed because
there is no operation to clean up the clone if the transaction is
aborted. Moreover, the datastructure swap happens on set element
activation.

This patch adds two new operations for sets: commit and abort, these new
operations are invoked from the commit and abort steps, after the
transactions have been digested, and it updates the pipapo set backend
to use it.

This patch adds a new ->pending_update field to sets to maintain a list
of sets that require this new commit and abort operations.

Fixes: 3c4287f620 ("nf_tables: Add set type for arbitrary concatenation of ranges")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-06-08 03:56:20 +02:00
Pablo Neira Ayuso
fa502c8656 netfilter: flowtable: simplify route logic
Grab reference to dst from skbuff earlier to simplify route caching.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
2023-05-18 08:48:55 +02:00
Christophe JAILLET
61e03e912d netfilter: Reorder fields in 'struct nf_conntrack_expect'
Group some variables based on their sizes to reduce holes.
On x86_64, this shrinks the size of 'struct nf_conntrack_expect' from 264
to 256 bytes.

This structure deserve a dedicated cache, so reducing its size looks nice.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
2023-05-18 08:48:54 +02:00
Pablo Neira Ayuso
c1592a8994 netfilter: nf_tables: deactivate anonymous set from preparation phase
Toggle deleted anonymous sets as inactive in the next generation, so
users cannot perform any update on it. Clear the generation bitmask
in case the transaction is aborted.

The following KASAN splat shows a set element deletion for a bound
anonymous set that has been already removed in the same transaction.

[   64.921510] ==================================================================
[   64.923123] BUG: KASAN: wild-memory-access in nf_tables_commit+0xa24/0x1490 [nf_tables]
[   64.924745] Write of size 8 at addr dead000000000122 by task test/890
[   64.927903] CPU: 3 PID: 890 Comm: test Not tainted 6.3.0+ #253
[   64.931120] Call Trace:
[   64.932699]  <TASK>
[   64.934292]  dump_stack_lvl+0x33/0x50
[   64.935908]  ? nf_tables_commit+0xa24/0x1490 [nf_tables]
[   64.937551]  kasan_report+0xda/0x120
[   64.939186]  ? nf_tables_commit+0xa24/0x1490 [nf_tables]
[   64.940814]  nf_tables_commit+0xa24/0x1490 [nf_tables]
[   64.942452]  ? __kasan_slab_alloc+0x2d/0x60
[   64.944070]  ? nf_tables_setelem_notify+0x190/0x190 [nf_tables]
[   64.945710]  ? kasan_set_track+0x21/0x30
[   64.947323]  nfnetlink_rcv_batch+0x709/0xd90 [nfnetlink]
[   64.948898]  ? nfnetlink_rcv_msg+0x480/0x480 [nfnetlink]

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-05-03 08:24:32 +02:00
Paolo Abeni
c248b27cfc Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-04-26 10:17:46 +02:00
Jakub Kicinski
ffcddcaed6 netfilter pull request 23-04-22
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Merge tag 'nf-next-23-04-22' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next

Pablo Neira Ayuso says:

====================
Netfilter/IPVS updates for net-next

1) Reduce jumpstack footprint: Stash chain in last rule marker in blob for
   tracing. Remove last rule and chain from jumpstack. From Florian Westphal.

2) nf_tables validates all tables before committing the new rules.
   Unfortunately, this has two drawbacks:

   - Since addition of the transaction mutex pernet state gets written to
     outside of the locked section from the cleanup callback, this is
     wrong so do this cleanup directly after table has passed all checks.

   - Revalidate tables that saw no changes. This can be avoided by
     keeping the validation state per table, not per netns.

   From Florian Westphal.

3) Get rid of a few redundant pointers in the traceinfo structure.
   The three removed pointers are used in the expression evaluation loop,
   so gcc keeps them in registers. Passing them to the (inlined) helpers
   thus doesn't increase nft_do_chain text size, while stack is reduced
   by another 24 bytes on 64bit arches. From Florian Westphal.

4) IPVS cleanups in several ways without implementing any functional
   changes, aside from removing some debugging output:

   - Update width of source for ip_vs_sync_conn_options
     The operation is safe, use an annotation to describe it properly.

   - Consistently use array_size() in ip_vs_conn_init()
     It seems better to use helpers consistently.

   - Remove {Enter,Leave}Function. These seem to be well past their
     use-by date.

   - Correct spelling in comments.

   From Simon Horman.

5) Extended netlink error report for netdevice in flowtables and
   netdev/chains. Allow for incrementally add/delete devices to netdev
   basechain. Allow to create netdev chain without device.

* tag 'nf-next-23-04-22' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next:
  netfilter: nf_tables: allow to create netdev chain without device
  netfilter: nf_tables: support for deleting devices in an existing netdev chain
  netfilter: nf_tables: support for adding new devices to an existing netdev chain
  netfilter: nf_tables: rename function to destroy hook list
  netfilter: nf_tables: do not send complete notification of deletions
  netfilter: nf_tables: extended netlink error reporting for netdevice
  ipvs: Correct spelling in comments
  ipvs: Remove {Enter,Leave}Function
  ipvs: Consistently use array_size() in ip_vs_conn_init()
  ipvs: Update width of source for ip_vs_sync_conn_options
  netfilter: nf_tables: do not store rule in traceinfo structure
  netfilter: nf_tables: do not store verdict in traceinfo structure
  netfilter: nf_tables: do not store pktinfo in traceinfo structure
  netfilter: nf_tables: remove unneeded conditional
  netfilter: nf_tables: make validation state per table
  netfilter: nf_tables: don't write table validation state without mutex
  netfilter: nf_tables: don't store chain address on jump
  netfilter: nf_tables: don't store address of last rule on jump
  netfilter: nf_tables: merge nft_rules_old structure and end of ruleblob marker
====================

Link: https://lore.kernel.org/r/20230421235021.216950-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-24 15:37:36 -07:00
Jakub Kicinski
9a82cdc28f bpf-next-for-netdev
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Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
pull-request: bpf-next 2023-04-21

We've added 71 non-merge commits during the last 8 day(s) which contain
a total of 116 files changed, 13397 insertions(+), 8896 deletions(-).

The main changes are:

1) Add a new BPF netfilter program type and minimal support to hook
   BPF programs to netfilter hooks such as prerouting or forward,
   from Florian Westphal.

2) Fix race between btf_put and btf_idr walk which caused a deadlock,
   from Alexei Starovoitov.

3) Second big batch to migrate test_verifier unit tests into test_progs
   for ease of readability and debugging, from Eduard Zingerman.

4) Add support for refcounted local kptrs to the verifier for allowing
   shared ownership, useful for adding a node to both the BPF list and
   rbtree, from Dave Marchevsky.

5) Migrate bpf_for(), bpf_for_each() and bpf_repeat() macros from BPF
  selftests into libbpf-provided bpf_helpers.h header and improve
  kfunc handling, from Andrii Nakryiko.

6) Support 64-bit pointers to kfuncs needed for archs like s390x,
   from Ilya Leoshkevich.

7) Support BPF progs under getsockopt with a NULL optval,
   from Stanislav Fomichev.

8) Improve verifier u32 scalar equality checking in order to enable
   LLVM transformations which earlier had to be disabled specifically
   for BPF backend, from Yonghong Song.

9) Extend bpftool's struct_ops object loading to support links,
   from Kui-Feng Lee.

10) Add xsk selftest follow-up fixes for hugepage allocated umem,
    from Magnus Karlsson.

11) Support BPF redirects from tc BPF to ifb devices,
    from Daniel Borkmann.

12) Add BPF support for integer type when accessing variable length
    arrays, from Feng Zhou.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (71 commits)
  selftests/bpf: verifier/value_ptr_arith converted to inline assembly
  selftests/bpf: verifier/value_illegal_alu converted to inline assembly
  selftests/bpf: verifier/unpriv converted to inline assembly
  selftests/bpf: verifier/subreg converted to inline assembly
  selftests/bpf: verifier/spin_lock converted to inline assembly
  selftests/bpf: verifier/sock converted to inline assembly
  selftests/bpf: verifier/search_pruning converted to inline assembly
  selftests/bpf: verifier/runtime_jit converted to inline assembly
  selftests/bpf: verifier/regalloc converted to inline assembly
  selftests/bpf: verifier/ref_tracking converted to inline assembly
  selftests/bpf: verifier/map_ptr_mixing converted to inline assembly
  selftests/bpf: verifier/map_in_map converted to inline assembly
  selftests/bpf: verifier/lwt converted to inline assembly
  selftests/bpf: verifier/loops1 converted to inline assembly
  selftests/bpf: verifier/jeq_infer_not_null converted to inline assembly
  selftests/bpf: verifier/direct_packet_access converted to inline assembly
  selftests/bpf: verifier/d_path converted to inline assembly
  selftests/bpf: verifier/ctx converted to inline assembly
  selftests/bpf: verifier/btf_ctx_access converted to inline assembly
  selftests/bpf: verifier/bpf_get_stack converted to inline assembly
  ...
====================

Link: https://lore.kernel.org/r/20230421211035.9111-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-21 20:32:37 -07:00
Pablo Neira Ayuso
b9703ed44f netfilter: nf_tables: support for adding new devices to an existing netdev chain
This patch allows users to add devices to an existing netdev chain.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-04-22 01:39:42 +02:00
Florian Westphal
46df417544 netfilter: nf_tables: do not store rule in traceinfo structure
pass it as argument instead.  This reduces size of traceinfo to
16 bytes.  Total stack usage:

 nf_tables_core.c:252 nft_do_chain    304     static

While its possible to also pass basechain as argument, doing so
increases nft_do_chaininfo function size.

Unlike pktinfo/verdict/rule the basechain info isn't used in
the expression evaluation path. gcc places it on the stack, which
results in extra push/pop when it gets passed to the trace helpers
as argument rather than as part of the traceinfo structure.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-04-22 01:39:41 +02:00
Florian Westphal
0a202145d5 netfilter: nf_tables: do not store verdict in traceinfo structure
Just pass it as argument to nft_trace_notify. Stack is reduced by 8 bytes:

nf_tables_core.c:256 nft_do_chain    312     static

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-04-22 01:39:41 +02:00
Florian Westphal
698bb828a6 netfilter: nf_tables: do not store pktinfo in traceinfo structure
pass it as argument.  No change in object size.

stack usage decreases by 8 byte:
 nf_tables_core.c:254  nft_do_chain       320     static

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-04-22 01:39:41 +02:00
Florian Westphal
00c320f9b7 netfilter: nf_tables: make validation state per table
We only need to validate tables that saw changes in the current
transaction.

The existing code revalidates all tables, but this isn't needed as
cross-table jumps are not allowed (chains have table scope).

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-04-22 01:39:40 +02:00
Florian Westphal
63e9bbbcca netfilter: nf_tables: don't store chain address on jump
Now that the rule trailer/end marker and the rcu head reside in the
same structure, we no longer need to save/restore the chain pointer
when performing/returning from a jump.

We can simply let the trace infra walk the evaluated rule until it
hits the end marker and then fetch the chain pointer from there.

When the rule is NULL (policy tracing), then chain and basechain
pointers were already identical, so just use the basechain.

This cuts size of jumpstack in half, from 256 to 128 bytes in 64bit,
scripts/stackusage says:

nf_tables_core.c:251 nft_do_chain    328     static

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-04-22 01:39:40 +02:00
Florian Westphal
fd9c663b9a bpf: minimal support for programs hooked into netfilter framework
This adds minimal support for BPF_PROG_TYPE_NETFILTER bpf programs
that will be invoked via the NF_HOOK() points in the ip stack.

Invocation incurs an indirect call.  This is not a necessity: Its
possible to add 'DEFINE_BPF_DISPATCHER(nf_progs)' and handle the
program invocation with the same method already done for xdp progs.

This isn't done here to keep the size of this chunk down.

Verifier restricts verdicts to either DROP or ACCEPT.

Signed-off-by: Florian Westphal <fw@strlen.de>
Link: https://lore.kernel.org/r/20230421170300.24115-3-fw@strlen.de
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-21 11:34:14 -07:00
Florian Westphal
84601d6ee6 bpf: add bpf_link support for BPF_NETFILTER programs
Add bpf_link support skeleton.  To keep this reviewable, no bpf program
can be invoked yet, if a program is attached only a c-stub is called and
not the actual bpf program.

Defaults to 'y' if both netfilter and bpf syscall are enabled in kconfig.

Uapi example usage:
	union bpf_attr attr = { };

	attr.link_create.prog_fd = progfd;
	attr.link_create.attach_type = 0; /* unused */
	attr.link_create.netfilter.pf = PF_INET;
	attr.link_create.netfilter.hooknum = NF_INET_LOCAL_IN;
	attr.link_create.netfilter.priority = -128;

	err = bpf(BPF_LINK_CREATE, &attr, sizeof(attr));

... this would attach progfd to ipv4:input hook.

Such hook gets removed automatically if the calling program exits.

BPF_NETFILTER program invocation is added in followup change.

NF_HOOK_OP_BPF enum will eventually be read from nfnetlink_hook, it
allows to tell userspace which program is attached at the given hook
when user runs 'nft hook list' command rather than just the priority
and not-very-helpful 'this hook runs a bpf prog but I can't tell which
one'.

Will also be used to disallow registration of two bpf programs with
same priority in a followup patch.

v4: arm32 cmpxchg only supports 32bit operand
    s/prio/priority/
v3: restrict prog attachment to ip/ip6 for now, lets lift restrictions if
    more use cases pop up (arptables, ebtables, netdev ingress/egress etc).

Signed-off-by: Florian Westphal <fw@strlen.de>
Link: https://lore.kernel.org/r/20230421170300.24115-2-fw@strlen.de
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-21 11:34:14 -07:00