In b380e5c ("netfilter: nf_tables: add message type to transactions"),
I used the wrong message type in the rule replacement case. The rule
that is replaced needs to be handled as a deleted rule.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Since 4fefee5 ("netfilter: nf_tables: allow to delete several objects
from a batch"), every new rule bumps the chain use counter. However,
this is limited to 16 bits, which means that it will overrun after
2^16 rules.
Use a u32 chain counter and check for overflows (just like we do for
table objects).
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The patch 5e94846 ("netfilter: nf_tables: add insert operation") did
not include RCU-safe list insertion when replacing rules.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Use GFP_ATOMIC allocations when sending removal notifications of
anonymous sets from rcu callback context. Sleeping in that context
is illegal.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Three changes to allow the deletion of several objects with dependencies
in one transaction, they are:
1) Introduce speculative counter increment/decrement that is undone in
the abort path if required, thus we avoid hitting -EBUSY when deleting
the chain. The counter updates are reverted in the abort path.
2) Increment/decrement table/chain use counter for each set/rule. We need
this to fully rely on the use counters instead of the list content,
eg. !list_empty(&chain->rules) which evaluate true in the middle of the
transaction.
3) Decrement table use counter when an anonymous set is bound to the
rule in the commit path. This avoids hitting -EBUSY when deleting
the table that contains anonymous sets. The anonymous sets are released
in the nf_tables_rule_destroy path. This should not be a problem since
the rule already bumped the use counter of the chain, so the bound
anonymous set reflects dependencies through the rule object, which
already increases the chain use counter.
So the general assumption after this patch is that the use counters are
bumped by direct object dependencies.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The patch c7c32e7 ("netfilter: nf_tables: defer all object release via
rcu") indicates that we always release deleted objects in the reverse
order, but that is only needed in the abort path. These are the two
possible scenarios when releasing objects:
1) Deletion scenario in the commit path: no need to release objects in
the reverse order since userspace already ensures that dependencies are
fulfilled), ie. userspace tells us to delete rule -> ... -> rule ->
chain -> table. In this case, we have to release the objects in the
*same order* as userspace provided.
2) Deletion scenario in the abort path: we have to iterate in the reverse
order to undo what it cannot be added, ie. userspace sent us a batch
that includes: table -> chain -> rule -> ... -> rule, and that needs to
be partially undone. In this case, we have to release objects in the
reverse order to ensure that the set and chain objects point to valid
rule and table objects.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The transaction needs to be placed at the end of the commit list,
otherwise event notifications are reordered and we may crash when
releasing object via call_rcu.
This problem was introduced in 60319eb ("netfilter: nf_tables: use new
transaction infrastructure to handle elements").
Reported-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pablo Neira Ayuso says:
====================
Netfilter/nftables updates for net-next
The following patchset contains Netfilter/nftables updates for net-next,
most relevantly they are:
1) Add set element update notification via netlink, from Arturo Borrero.
2) Put all object updates in one single message batch that is sent to
kernel-space. Before this patch only rules where included in the batch.
This series also introduces the generic transaction infrastructure so
updates to all objects (tables, chains, rules and sets) are applied in
an all-or-nothing fashion, these series from me.
3) Defer release of objects via call_rcu to reduce the time required to
commit changes. The assumption is that all objects are destroyed in
reverse order to ensure that dependencies betweem them are fulfilled
(ie. rules and sets are destroyed first, then chains, and finally
tables).
4) Allow to match by bridge port name, from Tomasz Bursztyka. This series
include two patches to prepare this new feature.
5) Implement the proper set selection based on the characteristics of the
data. The new infrastructure also allows you to specify your preferences
in terms of memory and computational complexity so the underlying set
type is also selected according to your needs, from Patrick McHardy.
6) Several cleanup patches for nft expressions, including one minor possible
compilation breakage due to missing mark support, also from Patrick.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that all objects are released in the reverse order via the
transaction infrastructure, we can enqueue the release via
call_rcu to save one synchronize_rcu. For small rule-sets loaded
via nft -f, it now takes around 50ms less here.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Instead of caching the original skbuff that contains the netlink
messages, this stores the netlink message sequence number, the
netlink portID and the report flag. This helps to prepare the
introduction of the object release via call_rcu.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Now that all these function are called from the commit path, we can
pass the context structure to reduce the amount of parameters in all
of the nf_tables_*_notify functions. This patch also removes unneeded
branches to check for skb, nlh and net that should be always set in
the context structure.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Leave the set content in consistent state if we fail to load the
batch. Use the new generic transaction infrastructure to achieve
this.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch speeds up rule-set updates and it also provides a way
to revert updates and leave things in consistent state in case that
the batch needs to be aborted.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch speeds up rule-set updates and it also introduces a way to
revert chain updates if the batch is aborted. The idea is to store the
changes in the transaction to apply that in the commit step.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch reworks the nf_tables API so set updates are included in
the same batch that contains rule updates. This speeds up rule-set
updates since we skip a dialog of four messages between kernel and
user-space (two on each direction), from:
1) create the set and send netlink message to the kernel
2) process the response from the kernel that contains the allocated name.
3) add the set elements and send netlink message to the kernel.
4) process the response from the kernel (to check for errors).
To:
1) add the set to the batch.
2) add the set elements to the batch.
3) add the rule that points to the set.
4) send batch to the kernel.
This also introduces an internal set ID (NFTA_SET_ID) that is unique
in the batch so set elements and rules can refer to new sets.
Backward compatibility has been only retained in userspace, this
means that new nft versions can talk to the kernel both in the new
and the old fashion.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The patch adds message type to the transaction to simplify the
commit the and abort routines. Yet another step forward in the
generalisation of the transaction infrastructure.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Move the commit and abort routines to the bottom of the source code
file. This change is required by the follow up patches that add the
set, chain and table transaction support.
This patch is just a cleanup to access several functions without
having to declare their prototypes.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch generalises the existing rule transaction infrastructure
so it can be used to handle set, table and chain object transactions
as well. The transaction provides a data area that stores private
information depending on the transaction type.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The new transaction infrastructure updates the family, table and chain
objects in the context structure, so let's deconstify them. While at it,
move the context structure initialization routine to the top of the
source file as it will be also used from the table and chain routines.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
To ensure family tight expression gets selected in priority to family
agnostic ones.
Signed-off-by: Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We currently have a limit of 8 * PAGE_SIZE anonymous sets. Lift that limit
by continuing the scan if the entire page is exhausted.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The intended format in request_module is %.*s instead of %*.s.
Reported-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Currently, nf_tables trims off the set name if it exceeeds 15
bytes, so explicitly reject set names that are too large.
Reported-by: Giuseppe Longo <giuseppelng@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch adds set_elems notifications. When a set_elem is
added/deleted, all listening peers in userspace will receive the
corresponding notification.
Signed-off-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@gnumonks.org>
The current set selection simply choses the first set type that provides
the requested features, which always results in the rbtree being chosen
by virtue of being the first set in the list.
What we actually want to do is choose the implementation that can provide
the requested features and is optimal from either a performance or memory
perspective depending on the characteristics of the elements and the
preferences specified by the user.
The elements are not known when creating a set. Even if we would provide
them for anonymous (literal) sets, we'd still have standalone sets where
the elements are not known in advance. We therefore need an abstract
description of the data charcteristics.
The kernel already knows the size of the key, this patch starts by
introducing a nested set description which so far contains only the maximum
amount of elements. Based on this the set implementations are changed to
provide an estimate of the required amount of memory and the lookup
complexity class.
The set ops have a new callback ->estimate() that is invoked during set
selection. It receives a structure containing the attributes known to the
kernel and is supposed to populate a struct nft_set_estimate with the
complexity class and, in case the size is known, the complete amount of
memory required, or the amount of memory required per element otherwise.
Based on the policy specified by the user (performance/memory, defaulting
to performance) the kernel will then select the best suited implementation.
Even if the set implementation would allow to add more than the specified
maximum amount of elements, they are enforced since new implementations
might not be able to add more than maximum based on which they were
selected.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Since we have the context available again, we can restore notifications
for destruction of anonymous sets.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
In order to fix set destruction notifications and get rid of unnecessary
members in private data structures, pass the context to expressions'
destructor functions again.
In order to do so, replace various members in the nft_rule_trans structure
by the full context.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The context argument logically comes first, and this is what every other
function dealing with contexts does.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This allows us to store user comment strings, but it could be also
used to store any kind of information that the user application needs
to link to the rule.
Scratch 8 bits for the new ulen field that indicates the length the
user data area. 4 bits from the handle (so it's 42 bits long, according
to Patrick, it would last 139 years with 1000 new rules per second)
and 4 bits from dlen (so the expression data area is 4K, which seems
sufficient by now even considering the compatibility layer).
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Patrick McHardy <kaber@trash.net>
Allow userspace to specify the queue number or the errno code for QUEUE
and DROP verdicts.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Fix access to uninitialized data for end interval elements. The
element data part is uninitialized in interval end elements.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This combination is not allowed since end interval elements cannot
contain data.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Patrick McHardy <kaber@trash.net>
We may lost race if we flush the rule-set (which happens asynchronously
via call_rcu) and we try to remove the table (that userspace assumes
to be empty).
Fix this by recovering synchronous rule and chain deletion. This was
introduced time ago before we had no batch support, and synchronous
rule deletion performance was not good. Now that we have the batch
support, we can just postpone the purge of old rule in a second step
in the commit phase. All object deletions are synchronous after this
patch.
As a side effect, we save memory as we don't need rcu_head per rule
anymore.
Cc: Patrick McHardy <kaber@trash.net>
Reported-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
For the reject module, we need to add AF-specific implementations to
get rid of incorrect module dependencies. Try to load an AF-specific
module first and fall back to generic modules.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Commit c9c8e48597 (netfilter: nf_tables: dump sets in all existing families)
changed nft_ctx_init_from_setattr() to only look up the address family if it
is not NFPROTO_UNSPEC. However if it is NFPROTO_UNSPEC and a table attribute
is given, nftables_afinfo_lookup() will dereference the NULL afi pointer.
Fix by checking for non-NULL afi and also move a check added by that commit
to the proper position.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The map that is used to allocate anonymous sets is indeed
BITS_PER_BYTE * PAGE_SIZE long.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The following commands trigger an oops:
# nft -i
nft> add table filter
nft> add chain filter input { type filter hook input priority 0; }
nft> add chain filter test
nft> add rule filter input jump test
nft> delete chain filter test
We need to check the chain use counter before allowing destruction since
we might have references from sets or jump rules.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=69341
Reported-by: Matthew Ife <deleriux1@gmail.com>
Tested-by: Matthew Ife <deleriux1@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When fetching the policy attribute, the byteorder conversion was
missing, breaking the chain policy setting.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We currently leak the set memory when deleting a table that still has
sets in it. Return EBUSY when attempting to delete a table with sets.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The table refers to data of the AF module, so we need to make sure the
module isn't unloaded while the table exists.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Simplifies error handling. Additionally use the correct type u32 for the
host byte order flags value.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Minor nf_chain_type cleanups:
- reorder struct to plug a hoe
- rename struct module member to "owner" for consistency
- rename nf_hookfn array to "hooks" for consistency
- reorder initializers for better readability
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
To avoid races, we need to replay to request after dropping the nfnl_mutex
to auto-load the chain type module.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
