Pull locking updates from Thomas Gleixner:
"A set of locking fixes and updates:
- Untangle the header spaghetti which causes build failures in
various situations caused by the lockdep additions to seqcount to
validate that the write side critical sections are non-preemptible.
- The seqcount associated lock debug addons which were blocked by the
above fallout.
seqcount writers contrary to seqlock writers must be externally
serialized, which usually happens via locking - except for strict
per CPU seqcounts. As the lock is not part of the seqcount, lockdep
cannot validate that the lock is held.
This new debug mechanism adds the concept of associated locks.
sequence count has now lock type variants and corresponding
initializers which take a pointer to the associated lock used for
writer serialization. If lockdep is enabled the pointer is stored
and write_seqcount_begin() has a lockdep assertion to validate that
the lock is held.
Aside of the type and the initializer no other code changes are
required at the seqcount usage sites. The rest of the seqcount API
is unchanged and determines the type at compile time with the help
of _Generic which is possible now that the minimal GCC version has
been moved up.
Adding this lockdep coverage unearthed a handful of seqcount bugs
which have been addressed already independent of this.
While generally useful this comes with a Trojan Horse twist: On RT
kernels the write side critical section can become preemtible if
the writers are serialized by an associated lock, which leads to
the well known reader preempts writer livelock. RT prevents this by
storing the associated lock pointer independent of lockdep in the
seqcount and changing the reader side to block on the lock when a
reader detects that a writer is in the write side critical section.
- Conversion of seqcount usage sites to associated types and
initializers"
* tag 'locking-urgent-2020-08-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits)
locking/seqlock, headers: Untangle the spaghetti monster
locking, arch/ia64: Reduce <asm/smp.h> header dependencies by moving XTP bits into the new <asm/xtp.h> header
x86/headers: Remove APIC headers from <asm/smp.h>
seqcount: More consistent seqprop names
seqcount: Compress SEQCNT_LOCKNAME_ZERO()
seqlock: Fold seqcount_LOCKNAME_init() definition
seqlock: Fold seqcount_LOCKNAME_t definition
seqlock: s/__SEQ_LOCKDEP/__SEQ_LOCK/g
hrtimer: Use sequence counter with associated raw spinlock
kvm/eventfd: Use sequence counter with associated spinlock
userfaultfd: Use sequence counter with associated spinlock
NFSv4: Use sequence counter with associated spinlock
iocost: Use sequence counter with associated spinlock
raid5: Use sequence counter with associated spinlock
vfs: Use sequence counter with associated spinlock
timekeeping: Use sequence counter with associated raw spinlock
xfrm: policy: Use sequence counters with associated lock
netfilter: nft_set_rbtree: Use sequence counter with associated rwlock
netfilter: conntrack: Use sequence counter with associated spinlock
sched: tasks: Use sequence counter with associated spinlock
...
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contains Netfilter fixes for net:
1) Flush the cleanup xtables worker to make sure destructors
have completed, from Florian Westphal.
2) iifgroup is matching erroneously, also from Florian.
3) Add selftest for meta interface matching, from Florian Westphal.
4) Move nf_ct_offload_timeout() to header, from Roi Dayan.
5) Call nf_ct_offload_timeout() from flow_offload_add() to
make sure garbage collection does not evict offloaded flow,
from Roi Dayan.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
To be used by callers from other modules.
[ Rename DAY to NF_CT_DAY to avoid possible symbol name pollution
issue --Pablo ]
Signed-off-by: Roi Dayan <roid@mellanox.com>
Reviewed-by: Oz Shlomo <ozsh@mellanox.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pablo Neira found that after recent update of xt_IDLETIMER the
iptables-nft tests sometimes show an error.
He tracked this down to the delayed cleanup used by nf_tables core:
del rule (transaction A)
add rule (transaction B)
Its possible that by time transaction B (both in same netns) runs,
the xt target destructor has not been invoked yet.
For native nft expressions this is no problem because all expressions
that have such side effects make sure these are handled from the commit
phase, rather than async cleanup.
For nft_compat however this isn't true.
Instead of forcing synchronous behaviour for nft_compat, keep track
of the number of outstanding destructor calls.
When we attempt to create a new expression, flush the cleanup worker
to make sure destructors have completed.
With lots of help from Pablo Neira.
Reported-by: Pablo Neira Ayso <pablo@netfilter.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
A sequence counter write side critical section must be protected by some
form of locking to serialize writers. A plain seqcount_t does not
contain the information of which lock must be held when entering a write
side critical section.
Use the new seqcount_spinlock_t data type, which allows to associate a
spinlock with the sequence counter. This enables lockdep to verify that
the spinlock used for writer serialization is held when the write side
critical section is entered.
If lockdep is disabled this lock association is compiled out and has
neither storage size nor runtime overhead.
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200720155530.1173732-15-a.darwish@linutronix.de
This new chain flag specifies that:
* the kernel dynamically allocates the chain name, if no chain name
is specified.
* If the immediate expression that refers to this chain is removed,
then this bound chain (and its content) is destroyed.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This enum definition was never exposed through UAPI. Rename
NFT_BASE_CHAIN to NFT_CHAIN_BASE for consistency.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This netlink attribute allows you to refer to chains inside a
transaction as an alternative to the name and the handle. The chain
binding support requires this new chain ID approach.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Currently, nf_flow_table_offload_add/del_cb are exported by nf_flow_table
module, therefore modules using them will have hard-dependency
on nf_flow_table and will require loading it all the time.
This can lead to an unnecessary overhead on systems that do not
use this API.
To relax the hard-dependency between the modules, we unexport these
functions and make them static inline.
Fixes: 978703f425 ("netfilter: flowtable: Add API for registering to flow table events")
Signed-off-by: Alaa Hleihel <alaa@mellanox.com>
Reviewed-by: Roi Dayan <roid@mellanox.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
Netfilter updates for net-next
The following patchset contains Netfilter updates for net-next
to extend ctnetlink and the flowtable infrastructure:
1) Extend ctnetlink kernel side netlink dump filtering capabilities,
from Romain Bellan.
2) Generalise the flowtable hook parser to take a hook list.
3) Pass a hook list to the flowtable hook registration/unregistration.
4) Add a helper function to release the flowtable hook list.
5) Update the flowtable event notifier to pass a flowtable hook list.
6) Allow users to add new devices to an existing flowtables.
7) Allow users to remove devices to an existing flowtables.
8) Allow for registering a flowtable with no initial devices.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This function schedules the flow teardown state and it forces a gc run.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conntrack dump does not support kernel side filtering (only get exists,
but it returns only one entry. And user has to give a full valid tuple)
It means that userspace has to implement filtering after receiving many
irrelevant entries, consuming resources (conntrack table is sometimes
very huge, much more than a routing table for example).
This patch adds filtering in kernel side. To achieve this goal, we:
* Add a new CTA_FILTER netlink attributes, actually a flag list to
parametize filtering
* Convert some *nlattr_to_tuple() functions, to allow a partial parsing
of CTA_TUPLE_ORIG and CTA_TUPLE_REPLY (so nf_conntrack_tuple it not
fully set)
Filtering is now possible on:
* IP SRC/DST values
* Ports for TCP and UDP flows
* IMCP(v6) codes types and IDs
Filtering is done as an "AND" operator. For example, when flags
PROTO_SRC_PORT, PROTO_NUM and IP_SRC are sets, only entries matching all
values are dumped.
Changes since v1:
Set NLM_F_DUMP_FILTERED in nlm flags if entries are filtered
Changes since v2:
Move several constants to nf_internals.h
Move a fix on netlink values check in a separate patch
Add a check on not-supported flags
Return EOPNOTSUPP if CDA_FILTER is set in ctnetlink_flush_conntrack
(not yet implemented)
Code style issues
Changes since v3:
Fix compilation warning reported by kbuild test robot
Changes since v4:
Fix a regression introduced in v3 (returned EINVAL for valid netlink
messages without CTA_MARK)
Changes since v5:
Change definition of CTA_FILTER_F_ALL
Fix a regression when CTA_TUPLE_ZONE is not set
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>
Move the bpf verifier trace check into the new switch statement in
HEAD.
Resolve the overlapping changes in hinic, where bug fixes overlap
the addition of VF support.
Signed-off-by: David S. Miller <davem@davemloft.net>
Gc step can queue offloaded flow del work or stats work.
Those work items can race each other and a flow could be freed
before the stats work is executed and querying it.
To avoid that, add a pending bit that if a work exists for a flow
don't queue another work for it.
This will also avoid adding multiple stats works in case stats work
didn't complete but gc step started again.
Signed-off-by: Paul Blakey <paulb@mellanox.com>
Reviewed-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
gcc-10 warns around a suspicious access to an empty struct member:
net/netfilter/nf_conntrack_core.c: In function '__nf_conntrack_alloc':
net/netfilter/nf_conntrack_core.c:1522:9: warning: array subscript 0 is outside the bounds of an interior zero-length array 'u8[0]' {aka 'unsigned char[0]'} [-Wzero-length-bounds]
1522 | memset(&ct->__nfct_init_offset[0], 0,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from net/netfilter/nf_conntrack_core.c:37:
include/net/netfilter/nf_conntrack.h:90:5: note: while referencing '__nfct_init_offset'
90 | u8 __nfct_init_offset[0];
| ^~~~~~~~~~~~~~~~~~
The code is correct but a bit unusual. Rework it slightly in a way that
does not trigger the warning, using an empty struct instead of an empty
array. There are probably more elegant ways to do this, but this is the
smallest change.
Fixes: c41884ce05 ("netfilter: conntrack: avoid zeroing timer")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Initialize set lookup matching element to NULL. Otherwise, the
NFT_LOOKUP_F_INV flag reverses the matching logic and it leads to
deference an uninitialized pointer to the matching element. Make sure
element data area and stateful expression are accessed if there is a
matching set element.
This patch undoes 24791b9aa1 ("netfilter: nft_set_bitmap: initialize set
element extension in lookups") which is not required anymore.
Fixes: 339706bc21 ("netfilter: nft_lookup: update element stateful expression")
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>
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>
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>
