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During nfhook traversal we only need a very small subset of
nf_hook_ops members.
We need:
- next element
- hook function to call
- hook function priv argument
Bridge netfilter also needs 'thresh'; can be obtained via ->orig_ops.
nf_hook_entry struct is now 32 bytes on x86_64.
A followup patch will turn the run-time list into an array that only
stores hook functions plus their priv arguments, eliminating the ->next
element.
Suggested-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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This allows easier future refactoring.
Signed-off-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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nf_defrag modules for ipv4 and ipv6 export an empty stub function.
Any module that needs the defragmentation hooks registered simply 'calls'
this empty function to create a phony module dependency -- modprobe will
then load the defrag module too.
This extends netfilter ipv4/ipv6 defragmentation modules to delay the hook
registration until the functionality is requested within a network namespace
instead of module load time for all namespaces.
Hooks are only un-registered on module unload or when a namespace that used
such defrag functionality exits.
We have to use struct net for this as the register hooks can be called
before netns initialization here from the ipv4/ipv6 conntrack module
init path.
There is no unregister functionality support, defrag will always be
active once it was requested inside a net namespace.
The reason is that defrag has impact on nft and iptables rulesets
(without defrag we might see framents).
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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This switch (default on) can be used to disable automatic registration
of connection tracking functionality in newly created network
namespaces.
This means that when net namespace goes down (or the tracker protocol
module is unloaded) we *might* have to unregister the hooks.
We can either add another per-netns variable that tells if
the hooks got registered by default, or, alternatively, just call
the protocol _put() function and have the callee deal with a possible
'extra' put() operation that doesn't pair with a get() one.
This uses the latter approach, i.e. a put() without a get has no effect.
Conntrack is still enabled automatically regardless of the new sysctl
setting if the new net namespace requires connection tracking, e.g. when
NAT rules are created.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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This makes use of nf_ct_netns_get/put added in previous patch.
We add get/put functions to nf_conntrack_l3proto structure, ipv4 and ipv6
then implement use-count to track how many users (nft or xtables modules)
have a dependency on ipv4 and/or ipv6 connection tracking functionality.
When count reaches zero, the hooks are unregistered.
This delays activation of connection tracking inside a namespace until
stateful firewall rule or nat rule gets added.
This patch breaks backwards compatibility in the sense that connection
tracking won't be active anymore when the protocol tracker module is
loaded. This breaks e.g. setups that ctnetlink for flow accounting and
the like, without any '-m conntrack' packet filter rules.
Followup patch restores old behavour and makes new delayed scheme
optional via sysctl.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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so that conntrack core will add the needed hooks in this namespace.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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MASQUERADE, S/DNAT and REDIRECT already call functions that depend on the
conntrack module.
However, since the conntrack hooks are now registered in a lazy fashion
(i.e., only when needed) a symbol reference is not enough.
Thus, when something is added to a nat table, make sure that it will see
packets by calling nf_ct_netns_get() which will register the conntrack
hooks in the current netns.
An alternative would be to add these dependencies to the NAT table.
However, that has problems when using non-modular builds -- we might
register e.g. ipv6 conntrack before its initcall has run, leading to NULL
deref crashes since its per-netns storage has not yet been allocated.
Adding the dependency in the modules instead has the advantage that nat
table also does not register its hooks until rules are added.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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currently aliased to try_module_get/_put.
Will be changed in next patch when we add functions to make use of ->net
argument to store usercount per l3proto tracker.
This is needed to avoid registering the conntrack hooks in all netns and
later only enable connection tracking in those that need conntrack.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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since adf0516845bcd0 ("netfilter: remove ip_conntrack* sysctl compat code")
the only user (ipv4 tracker) sets this to an empty stub function.
After this change nf_ct_l3proto_pernet_register() is also empty,
but this will change in a followup patch to add conditional register
of the hooks.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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CONFIG_NF_CT_PROTO_UDPLITE is no more a tristate. When set to y,
connection tracking support for UDPlite protocol is built-in into
nf_conntrack.ko.
footprint test:
$ ls -l net/netfilter/nf_conntrack{_proto_udplite,}.ko \
net/ipv4/netfilter/nf_conntrack_ipv4.ko \
net/ipv6/netfilter/nf_conntrack_ipv6.ko
(builtin)|| udplite| ipv4 | ipv6 |nf_conntrack
---------++--------+--------+--------+--------------
none || 432538 | 828755 | 828676 | 6141434
UDPlite || - | 829649 | 829362 | 6498204
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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CONFIG_NF_CT_PROTO_SCTP is no more a tristate. When set to y, connection
tracking support for SCTP protocol is built-in into nf_conntrack.ko.
footprint test:
$ ls -l net/netfilter/nf_conntrack{_proto_sctp,}.ko \
net/ipv4/netfilter/nf_conntrack_ipv4.ko \
net/ipv6/netfilter/nf_conntrack_ipv6.ko
(builtin)|| sctp | ipv4 | ipv6 | nf_conntrack
---------++--------+--------+--------+--------------
none || 498243 | 828755 | 828676 | 6141434
SCTP || - | 829254 | 829175 | 6547872
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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CONFIG_NF_CT_PROTO_DCCP is no more a tristate. When set to y, connection
tracking support for DCCP protocol is built-in into nf_conntrack.ko.
footprint test:
$ ls -l net/netfilter/nf_conntrack{_proto_dccp,}.ko \
net/ipv4/netfilter/nf_conntrack_ipv4.ko \
net/ipv6/netfilter/nf_conntrack_ipv6.ko
(builtin)|| dccp | ipv4 | ipv6 | nf_conntrack
---------++--------+--------+--------+--------------
none || 469140 | 828755 | 828676 | 6141434
DCCP || - | 830566 | 829935 | 6533526
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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To allow usage of enum ip_conntrack_dir in include/net/netns/conntrack.h,
this patch encloses #include <linux/netfilter.h> in a #ifndef __KERNEL__
directive, so that compiler errors caused by unwanted inclusion of
include/linux/netfilter.h are avoided.
In addition, #include <linux/netfilter/nf_conntrack_common.h> line has
been added to resolve correctly CTINFO2DIR macro.
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Acked-by: Mikko Rapeli <mikko.rapeli@iki.fi>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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So we can autoload nfnetlink_log.ko when the user adding nft log
group X rule in netdev family.
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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In netdev family, we will handle non ethernet packets, so using
eth_hdr(skb)->h_proto is incorrect.
Meanwhile, we can use socket(AF_PACKET...) to sending packets, so
skb->protocol is not always set in bridge family.
Add an extra parameter into nf_log_l2packet to solve this issue.
Fixes: 1fddf4bad0ac ("netfilter: nf_log: add packet logging for netdev family")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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CONFIG_NF_NAT_PROTO_UDPLITE is no more a tristate. When set to y, NAT
support for UDPlite protocol is built-in into nf_nat.ko.
footprint test:
(nf_nat_proto_) |udplite || nf_nat
--------------------------+--------++--------
no builtin | 408048 || 2241312
UDPLITE builtin | - || 2577256
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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CONFIG_NF_NAT_PROTO_SCTP is no more a tristate. When set to y, NAT
support for SCTP protocol is built-in into nf_nat.ko.
footprint test:
(nf_nat_proto_) | sctp || nf_nat
--------------------------+--------++--------
no builtin | 428344 || 2241312
SCTP builtin | - || 2597032
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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CONFIG_NF_NAT_PROTO_DCCP is no more a tristate. When set to y, NAT
support for DCCP protocol is built-in into nf_nat.ko.
footprint test:
(nf_nat_proto_) | dccp || nf_nat
--------------------------+--------++--------
no builtin | 409800 || 2241312
DCCP builtin | - || 2578968
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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The email address has changed, let's update the copyright statements.
Signed-off-by: Arturo Borrero Gonzalez <arturo@debian.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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Implemented RFC7527 Enhanced DAD.
IPv6 duplicate address detection can fail if there is some temporary
loopback of Ethernet frames. RFC7527 solves this by including a random
nonce in the NS messages used for DAD, and if an NS is received with the
same nonce it is assumed to be a looped back DAD probe and is ignored.
RFC7527 is enabled by default. Can be disabled by setting both of
conf/{all,interface}/enhanced_dad to zero.
Signed-off-by: Erik Nordmark <nordmark@arista.com>
Signed-off-by: Bob Gilligan <gilligan@arista.com>
Reviewed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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The mv88e6390 has a number flow control registers accessed via the
Flow Control register. Use these to set the pause control.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
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The mv88e6390 has a different mechanism for configuring pause.
Refactor the code into an ops function, and for the moment, don't add
any mv88e6390 code yet.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
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There are two different rate limiting configurations, depending on the
switch generation. Refactor this into ops.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Some switches support jumbo frames. Refactor this code into operations
in the ops structure.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Older devices have a couple of registers in global2. The mv88e6390
family has a single register in global1 behind which hides similar
configuration. Implement and op for this.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Older chips only support DSA tagging. Newer chips have both DSA and
EDSA tagging. Refactor the code by adding port functions for setting the
frame mode, egress mode, and if to forward unknown frames.
This results in the helper mv88e6xxx_6065_family() becoming unused, so
remove it.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
v3:
Verify mandatory ops for port setup
Don't set ether type for DSA port.
Signed-off-by: David S. Miller <davem@davemloft.net>
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Older chips support a single tagging protocol, DSA. New chips support
both DSA and EDSA, an enhanced version. Having both as an option
changes the register layouts. Up until now, it has been assumed that
if EDSA is supported, it will be used. Hence the register layout has
been determined by which protocol should be used. However, mv88e6390
has a different implementation of EDSA, which requires we need to use
the DSA tagging. Hence separate the selection of the protocol from the
register layout.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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The mv88e6390 changes the monitor control register into the Monitor
and Management control, which is an indirection register to various
registers.
Add ops to set the CPU port and the ingress/egress port for both
register layouts, to global1
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
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The mv88e6390 does not have the two registers to set the frame
priority map. Instead it has an indirection registers for setting a
number of different priority maps. Refactor the old code into an
function, implement the mv88e6390 version, and use an op to call the
right one.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Commit b90eb7549499 ("fib: introduce FIB notification infrastructure")
introduced a new notification chain to notify listeners (f.e., switchdev
drivers) about addition and deletion of routes.
However, upon registration to the chain the FIB tables can already be
populated, which means potential listeners will have an incomplete view
of the tables.
Solve that by dumping the FIB tables and replaying the events to the
passed notification block. The dump itself is done using RCU in order
not to starve consumers that need RTNL to make progress.
The integrity of the dump is ensured by reading the FIB change sequence
counter before and after the dump under RTNL. This allows us to avoid
the problematic situation in which the dumping process sends a ENTRY_ADD
notification following ENTRY_DEL generated by another process holding
RTNL.
Callers of the registration function may pass a callback that is
executed in case the dump was inconsistent with current FIB tables.
The number of retries until a consistent dump is achieved is set to a
fixed number to prevent callers from looping for long periods of time.
In case current limit proves to be problematic in the future, it can be
easily converted to be configurable using a sysctl.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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The next patch will enable listeners of the FIB notification chain to
request a dump of the FIB tables. However, since RTNL isn't taken during
the dump, it's possible for the FIB tables to change mid-dump, which
will result in inconsistency between the listener's table and the
kernel's.
Allow listeners to know about changes that occurred mid-dump, by adding
a change sequence counter to each net namespace. The counter is
incremented just before a notification is sent in the FIB chain.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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In order not to hold RTNL for long periods of time we're going to dump
the FIB tables using RCU.
Convert the FIB notification chain to be atomic, as we can't block in
RCU critical sections.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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We can miss FIB notifications sent between the time the ports were
created and the FIB notification block registered.
Instead of receiving these notifications only when they are replayed for
the FIB notification block during registration, just register the
notification block before the ports are created.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Convert rocker to offload FIBs in deferred work in a similar fashion to
mlxsw, which was converted in the previous commits.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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As explained in the previous commits, we need to process FIB entries
addition / deletion events in FIFO order or otherwise we can have a
mismatch between the kernel's FIB table and the device's.
Create an ordered workqueue for rocker to which these work items will be
submitted to.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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FIB offload is currently done in process context with RTNL held, but
we're about to dump the FIB tables in RCU critical section, so we can no
longer sleep.
Instead, defer the operation to process context using deferred work. Make
sure fib info isn't freed while the work is queued by taking a reference
on it and releasing it after the operation is done.
Deferring the operation is valid because the upper layers always assume
the operation was successful. If it's not, then the driver-specific
abort mechanism is called and all routed traffic is directed to slow
path.
The work items are submitted to an ordered workqueue to prevent a
mismatch between the kernel's FIB table and the device's.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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We're going to start processing FIB entries addition / deletion events
in deferred work. These work items must be processed in the order they
were submitted or otherwise we can have differences between the kernel's
FIB table and the device's.
Solve this by creating an ordered workqueue to which these work items
will be submitted to. Note that we can't simply convert the current
workqueue to be ordered, as EMADs re-transmissions are also processed in
deferred work.
Later on, we can migrate other work items to this workqueue, such as FDB
notification processing and nexthop resolution, since they all take the
same lock anyway.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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As explained in the previous commit, modules are going to need to take a
reference on fib info and then drop it using fib_info_put().
Add the fib_info_hold() helper to make the code more readable and also
symmetric with fib_info_put().
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Suggested-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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The FIB notification chain is going to be converted to an atomic chain,
which means switchdev drivers will have to offload FIB entries in
deferred work, as hardware operations entail sleeping.
However, while the work is queued fib info might be freed, so a
reference must be taken. To release the reference (and potentially free
the fib info) fib_info_put() will be called, which in turn calls
free_fib_info().
Export free_fib_info() so that modules will be able to invoke
fib_info_put().
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Fixes: 255cb30425c0 ("net/sched: act_mirred: Add new tc_action_ops get_dev()")
Cc: Hadar Hen Zion <hadarh@mellanox.com>
Cc: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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The commit of SOF_TIMESTAMPING_OPT_STATS didn't include the
new header for avr32, causing build to break. The patch fixes it.
Fixes: 1c885808e456 ("tcp: SOF_TIMESTAMPING_OPT_STATS option for SO_TIMESTAMPING")
Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Before commit 850cbaddb52d ("udp: use it's own memory accounting
schema"), the udp protocol allowed sk_rmem_alloc to grow beyond
the rcvbuf by the whole current packet's truesize. After said commit
we allow sk_rmem_alloc to exceed the rcvbuf only if the receive queue
is empty. As reported by Jesper this cause a performance regression
for some (small) values of rcvbuf.
This commit is intended to fix the regression restoring the old
handling of the rcvbuf limit.
Reported-by: Jesper Dangaard Brouer <brouer@redhat.com>
Fixes: 850cbaddb52d ("udp: use it's own memory accounting schema")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Under heavy stress, timer used in estimators tend to slowly be delayed
by a few jiffies, leading to inaccuracies.
Lets remember what was the last scheduled jiffies so that we get more
precise estimations, without having to add a multiply/divide in the loop
to account for the drifts.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Logically, EFX_BUG_ON_PARANOID can never be correct. For, BUG_ON should
only be used if it is not possible to continue without potential harm;
and since the non-DEBUG driver will continue regardless (as the BUG_ON is
compiled out), clearly the BUG_ON cannot be needed in the DEBUG driver.
So, replace every EFX_BUG_ON_PARANOID with either an EFX_WARN_ON_PARANOID
or the newly defined EFX_WARN_ON_ONCE_PARANOID.
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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This patch adds the sample program test_cgrp2_attach2. This program is
similar to test_cgrp2_attach, but it performs automated testing of the
cgroupv2 BPF attached filters. It runs the following checks:
* Simple filter attachment
* Application of filters to child cgroups
* Overriding filters on child cgroups
* Checking that this still works when the parent filter is removed
The filters that are used here are simply allow all / deny all filters, so
it isn't checking the actual functionality of the filters, but rather
the behaviour around detachment / attachment. If net_cls is enabled,
this test will fail.
Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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This patch modifies test_current_task_under_cgroup_user. The test has
several helpers around creating a temporary environment for cgroup
testing, and moving the current task around cgroups. This set of
helpers can then be used in other tests.
Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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silence some of the clang compiler warnings like:
include/linux/fs.h:2693:9: warning: comparison of unsigned enum expression < 0 is always false
arch/x86/include/asm/processor.h:491:30: warning: taking address of packed member 'sp0' of class or structure 'x86_hw_tss' may result in an unaligned pointer value
include/linux/cgroup-defs.h:326:16: warning: field 'cgrp' with variable sized type 'struct cgroup' not at the end of a struct or class is a GNU extension
since they add too much noise to samples/bpf/ build.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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net_generic() function is both a) inline and b) used ~600 times.
It has the following code inside
...
ptr = ng->ptr[id - 1];
...
"id" is never compile time constant so compiler is forced to subtract 1.
And those decrements or LEA [r32 - 1] instructions add up.
We also start id'ing from 1 to catch bugs where pernet sybsystem id
is not initialized and 0. This is quite pointless idea (nothing will
work or immediate interference with first registered subsystem) in
general but it hints what needs to be done for code size reduction.
Namely, overlaying allocation of pointer array and fixed part of
structure in the beginning and using usual base-0 addressing.
Ids are just cookies, their exact values do not matter, so lets start
with 3 on x86_64.
Code size savings (oh boy): -4.2 KB
As usual, ignore the initial compiler stupidity part of the table.
add/remove: 0/0 grow/shrink: 12/670 up/down: 89/-4297 (-4208)
function old new delta
tipc_nametbl_insert_publ 1250 1270 +20
nlmclnt_lookup_host 686 703 +17
nfsd4_encode_fattr 5930 5941 +11
nfs_get_client 1050 1061 +11
register_pernet_operations 333 342 +9
tcf_mirred_init 843 849 +6
tcf_bpf_init 1143 1149 +6
gss_setup_upcall 990 994 +4
idmap_name_to_id 432 434 +2
ops_init 274 275 +1
nfsd_inject_forget_client 259 260 +1
nfs4_alloc_client 612 613 +1
tunnel_key_walker 164 163 -1
...
tipc_bcbase_select_primary 392 360 -32
mac80211_hwsim_new_radio 2808 2767 -41
ipip6_tunnel_ioctl 2228 2186 -42
tipc_bcast_rcv 715 672 -43
tipc_link_build_proto_msg 1140 1089 -51
nfsd4_lock 3851 3796 -55
tipc_mon_rcv 1012 956 -56
Total: Before=156643951, After=156639743, chg -0.00%
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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This is precursor to fixing "[id - 1]" bloat inside net_generic().
Name "s" is chosen to complement name "u" often used for dummy unions.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Publishing net_generic pointer is done with silly mistake: new array is
published BEFORE setting freshly acquired pernet subsystem pointer.
memcpy
rcu_assign_pointer
kfree_rcu
ng->ptr[id - 1] = data;
This bug was introduced with commit dec827d174d7f76c457238800183ca864a639365
("[NETNS]: The generic per-net pointers.") in the glorious days of
chopping networking stack into containers proper 8.5 years ago (whee...)
How it didn't trigger for so long?
Well, you need quite specific set of conditions:
*) race window opens once per pernet subsystem addition
(read: modprobe or boot)
*) not every pernet subsystem is eligible (need ->id and ->size)
*) not every pernet subsystem is vulnerable (need incorrect or absense
of ordering of register_pernet_sybsys() and actually using net_generic())
*) to hide the bug even more, default is to preallocate 13 pointers which
is actually quite a lot. You need IPv6, netfilter, bridging etc together
loaded to trigger reallocation in the first place. Trimmed down
config are OK.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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