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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
