Add an optimized payload expression implementation for small (up to 4 bytes)
aligned data loads from the linear packet area.
This patch also includes original Patrick McHardy's entitled (nf_tables:
inline nft_payload_fast_eval() into main evaluation loop).
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add an optimized version of nft_data_cmp() that only handles values of to
4 bytes length.
This patch includes original Patrick McHardy's patch entitled (nf_tables:
inline nft_cmp_fast_eval() into main evaluation loop).
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Split the expression ops into two parts and support overloading of
the runtime expression ops based on the requested function through
a ->select_ops() callback.
This can be used to provide optimized implementations, for instance
for loading small aligned amounts of data from the packet or inlining
frequently used operations into the main evaluation loop.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch adds the new netlink API for maintaining nf_tables sets
independently of the ruleset. The API supports the following operations:
- creation of sets
- deletion of sets
- querying of specific sets
- dumping of all sets
- addition of set elements
- removal of set elements
- dumping of all set elements
Sets are identified by name, each table defines an individual namespace.
The name of a set may be allocated automatically, this is mostly useful
in combination with the NFT_SET_ANONYMOUS flag, which destroys a set
automatically once the last reference has been released.
Sets can be marked constant, meaning they're not allowed to change while
linked to a rule. This allows to perform lockless operation for set
types that would otherwise require locking.
Additionally, if the implementation supports it, sets can (as before) be
used as maps, associating a data value with each key (or range), by
specifying the NFT_SET_MAP flag and can be used for interval queries by
specifying the NFT_SET_INTERVAL flag.
Set elements are added and removed incrementally. All element operations
support batching, reducing netlink message and set lookup overhead.
The old "set" and "hash" expressions are replaced by a generic "lookup"
expression, which binds to the specified set. Userspace is not aware
of the actual set implementation used by the kernel anymore, all
configuration options are generic.
Currently the implementation selection logic is largely missing and the
kernel will simply use the first registered implementation supporting the
requested operation. Eventually, the plan is to have userspace supply a
description of the data characteristics and select the implementation
based on expected performance and memory use.
This patch includes the new 'lookup' expression to look up for element
matching in the set.
This patch includes kernel-doc descriptions for this set API and it
also includes the following fixes.
From Patrick McHardy:
* netfilter: nf_tables: fix set element data type in dumps
* netfilter: nf_tables: fix indentation of struct nft_set_elem comments
* netfilter: nf_tables: fix oops in nft_validate_data_load()
* netfilter: nf_tables: fix oops while listing sets of built-in tables
* netfilter: nf_tables: destroy anonymous sets immediately if binding fails
* netfilter: nf_tables: propagate context to set iter callback
* netfilter: nf_tables: add loop detection
From Pablo Neira Ayuso:
* netfilter: nf_tables: allow to dump all existing sets
* netfilter: nf_tables: fix wrong type for flags variable in newelem
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch adds nftables which is the intended successor of iptables.
This packet filtering framework reuses the existing netfilter hooks,
the connection tracking system, the NAT subsystem, the transparent
proxying engine, the logging infrastructure and the userspace packet
queueing facilities.
In a nutshell, nftables provides a pseudo-state machine with 4 general
purpose registers of 128 bits and 1 specific purpose register to store
verdicts. This pseudo-machine comes with an extensible instruction set,
a.k.a. "expressions" in the nftables jargon. The expressions included
in this patch provide the basic functionality, they are:
* bitwise: to perform bitwise operations.
* byteorder: to change from host/network endianess.
* cmp: to compare data with the content of the registers.
* counter: to enable counters on rules.
* ct: to store conntrack keys into register.
* exthdr: to match IPv6 extension headers.
* immediate: to load data into registers.
* limit: to limit matching based on packet rate.
* log: to log packets.
* meta: to match metainformation that usually comes with the skbuff.
* nat: to perform Network Address Translation.
* payload: to fetch data from the packet payload and store it into
registers.
* reject (IPv4 only): to explicitly close connection, eg. TCP RST.
Using this instruction-set, the userspace utility 'nft' can transform
the rules expressed in human-readable text representation (using a
new syntax, inspired by tcpdump) to nftables bytecode.
nftables also inherits the table, chain and rule objects from
iptables, but in a more configurable way, and it also includes the
original datatype-agnostic set infrastructure with mapping support.
This set infrastructure is enhanced in the follow up patch (netfilter:
nf_tables: add netlink set API).
This patch includes the following components:
* the netlink API: net/netfilter/nf_tables_api.c and
include/uapi/netfilter/nf_tables.h
* the packet filter core: net/netfilter/nf_tables_core.c
* the expressions (described above): net/netfilter/nft_*.c
* the filter tables: arp, IPv4, IPv6 and bridge:
net/ipv4/netfilter/nf_tables_ipv4.c
net/ipv6/netfilter/nf_tables_ipv6.c
net/ipv4/netfilter/nf_tables_arp.c
net/bridge/netfilter/nf_tables_bridge.c
* the NAT table (IPv4 only):
net/ipv4/netfilter/nf_table_nat_ipv4.c
* the route table (similar to mangle):
net/ipv4/netfilter/nf_table_route_ipv4.c
net/ipv6/netfilter/nf_table_route_ipv6.c
* internal definitions under:
include/net/netfilter/nf_tables.h
include/net/netfilter/nf_tables_core.h
* It also includes an skeleton expression:
net/netfilter/nft_expr_template.c
and the preliminary implementation of the meta target
net/netfilter/nft_meta_target.c
It also includes a change in struct nf_hook_ops to add a new
pointer to store private data to the hook, that is used to store
the rule list per chain.
This patch is based on the patch from Patrick McHardy, plus merged
accumulated cleanups, fixes and small enhancements to the nftables
code that has been done since 2009, which are:
From Patrick McHardy:
* nf_tables: adjust netlink handler function signatures
* nf_tables: only retry table lookup after successful table module load
* nf_tables: fix event notification echo and avoid unnecessary messages
* nft_ct: add l3proto support
* nf_tables: pass expression context to nft_validate_data_load()
* nf_tables: remove redundant definition
* nft_ct: fix maxattr initialization
* nf_tables: fix invalid event type in nf_tables_getrule()
* nf_tables: simplify nft_data_init() usage
* nf_tables: build in more core modules
* nf_tables: fix double lookup expression unregistation
* nf_tables: move expression initialization to nf_tables_core.c
* nf_tables: build in payload module
* nf_tables: use NFPROTO constants
* nf_tables: rename pid variables to portid
* nf_tables: save 48 bits per rule
* nf_tables: introduce chain rename
* nf_tables: check for duplicate names on chain rename
* nf_tables: remove ability to specify handles for new rules
* nf_tables: return error for rule change request
* nf_tables: return error for NLM_F_REPLACE without rule handle
* nf_tables: include NLM_F_APPEND/NLM_F_REPLACE flags in rule notification
* nf_tables: fix NLM_F_MULTI usage in netlink notifications
* nf_tables: include NLM_F_APPEND in rule dumps
From Pablo Neira Ayuso:
* nf_tables: fix stack overflow in nf_tables_newrule
* nf_tables: nft_ct: fix compilation warning
* nf_tables: nft_ct: fix crash with invalid packets
* nft_log: group and qthreshold are 2^16
* nf_tables: nft_meta: fix socket uid,gid handling
* nft_counter: allow to restore counters
* nf_tables: fix module autoload
* nf_tables: allow to remove all rules placed in one chain
* nf_tables: use 64-bits rule handle instead of 16-bits
* nf_tables: fix chain after rule deletion
* nf_tables: improve deletion performance
* nf_tables: add missing code in route chain type
* nf_tables: rise maximum number of expressions from 12 to 128
* nf_tables: don't delete table if in use
* nf_tables: fix basechain release
From Tomasz Bursztyka:
* nf_tables: Add support for changing users chain's name
* nf_tables: Change chain's name to be fixed sized
* nf_tables: Add support for replacing a rule by another one
* nf_tables: Update uapi nftables netlink header documentation
From Florian Westphal:
* nft_log: group is u16, snaplen u32
From Phil Oester:
* nf_tables: operational limit match
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Correct common misspelling of "identify" as "indentify" throughout
the kernel
Signed-off-by: Maxime Jayat <maxime@artisandeveloppeur.fr>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Similar to nat_decode_session, alloc_null_binding is needed for both
ip_tables and nf_tables, so move it to nf_nat_core.c. This change
is required by nf_tables.
This is an adapted version of the original patch from Patrick McHardy.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pass the hook ops to the hookfn to allow for generic hook
functions. This change is required by nf_tables.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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Merge tag 'v3.12-rc4' into sched/core
Merge Linux v3.12-rc4 to fix a conflict and also to refresh the tree
before applying more scheduler patches.
Conflicts:
arch/avr32/include/asm/Kbuild
Signed-off-by: Ingo Molnar <mingo@kernel.org>
TCP listener refactoring, part 4 :
To speed up inet lookups, we moved IPv4 addresses from inet to struct
sock_common
Now is time to do the same for IPv6, because it permits us to have fast
lookups for all kind of sockets, including upcoming SYN_RECV.
Getting IPv6 addresses in TCP lookups currently requires two extra cache
lines, plus a dereference (and memory stall).
inet6_sk(sk) does the dereference of inet_sk(__sk)->pinet6
This patch is way bigger than its IPv4 counter part, because for IPv4,
we could add aliases (inet_daddr, inet_rcv_saddr), while on IPv6,
it's not doable easily.
inet6_sk(sk)->daddr becomes sk->sk_v6_daddr
inet6_sk(sk)->rcv_saddr becomes sk->sk_v6_rcv_saddr
And timewait socket also have tw->tw_v6_daddr & tw->tw_v6_rcv_saddr
at the same offset.
We get rid of INET6_TW_MATCH() as INET6_MATCH() is now the generic
macro.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
The following patchset contains Netfilter updates for your net-next tree,
mostly ipset improvements and enhancements features, they are:
* Don't call ip_nest_end needlessly in the error path from me, suggested
by Pablo Neira Ayuso, from Jozsef Kadlecsik.
* Fixed sparse warnings about shadowed variable and missing rcu annotation
and fix of "may be used uninitialized" warnings, also from Jozsef.
* Renamed simple macro names to avoid namespace issues, reported by David
Laight, again from Jozsef.
* Use fix sized type for timeout in the extension part, and cosmetic
ordering of matches and targets separatedly in xt_set.c, from Jozsef.
* Support package fragments for IPv4 protos without ports from Anders K.
Pedersen. For example this allows a hash:ip,port ipset containing the
entry 192.168.0.1,gre:0 to match all package fragments for PPTP VPN
tunnels to/from the host. Without this patch only the first package
fragment (with fragment offset 0) was matched.
* Introduced a new operation to get both setname and family, from Jozsef.
ip[6]tables set match and SET target need to know the family of the set
in order to reject adding rules which refer to a set with a non-mathcing
family. Currently such rules are silently accepted and then ignored
instead of generating an error message to the user.
* Reworked extensions support in ipset types from Jozsef. The approach of
defining structures with all variations is not manageable as the
number of extensions grows. Therefore a blob for the extensions is
introduced, somewhat similar to conntrack. The support of extensions
which need a per data destroy function is added as well.
* When an element timed out in a list:set type of set, the garbage
collector skipped the checking of the next element. So the purging
was delayed to the next run of the gc, fixed by Jozsef.
* A small Kconfig fix: NETFILTER_NETLINK cannot be selected and
ipset requires it.
* hash:net,net type from Oliver Smith. The type provides the ability to
store pairs of subnets in a set.
* Comment for ipset entries from Oliver Smith. This makes possible to
annotate entries in a set with comments, for example:
ipset n foo hash:net,net comment
ipset a foo 10.0.0.0/21,192.168.1.0/24 comment "office nets A and B"
* Fix of hash types resizing with comment extension from Jozsef.
* Fix of new extensions for list:set type when an element is added
into a slot from where another element was pushed away from Jozsef.
* Introduction of a common function for the listing of the element
extensions from Jozsef.
* Net namespace support for ipset from Vitaly Lavrov.
* hash:net,port,net type from Oliver Smith, which makes possible
to store the triples of two subnets and a protocol, port pair in
a set.
* Get xt_TCPMSS working with net namespace, by Gao feng.
* Use the proper net netnamespace to allocate skbs, also by Gao feng.
* A couple of cleanups for the conntrack SIP helper, by Holger
Eitzenberger.
* Extend cttimeout to allow setting default conntrack timeouts via
nfnetlink, so we can get rid of all our sysctl/proc interfaces in
the future for timeout tuning, from me.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Change all __wait_event*() implementations to match the corresponding
wait_event*() signature for convenience.
In particular this does away with the weird 'ret' logic. Since there
are __wait_event*() users this requires we update them too.
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20131002092529.042563462@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pablo Neira Ayuso says:
====================
The following patchset contains Netfilter/IPVS fixes for your net
tree, they are:
* Fix BUG_ON splat due to malformed TCP packets seen by synproxy, from
Patrick McHardy.
* Fix possible weight overflow in lblc and lblcr schedulers due to
32-bits arithmetics, from Simon Kirby.
* Fix possible memory access race in the lblc and lblcr schedulers,
introduced when it was converted to use RCU, two patches from
Julian Anastasov.
* Fix hard dependency on CPU 0 when reading per-cpu stats in the
rate estimator, from Julian Anastasov.
* Fix race that may lead to object use after release, when invoking
ipvsadm -C && ipvsadm -R, introduced when adding RCU, from Julian
Anastasov.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Default timeouts are currently set via proc/sysctl interface, the
typical pattern is a file name like:
/proc/sys/net/netfilter/nf_conntrack_PROTOCOL_timeout_STATE
This results in one entry per default protocol state timeout.
This patch simplifies this by allowing to set default protocol
timeouts via cttimeout netlink interface.
This should allow us to get rid of the existing proc/sysctl code
in the midterm.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
There are currently seven different NAT hooks used in both
nf_conntrack_sip and nf_nat_sip, each of the hooks is exported in
nf_conntrack_sip, then set from the nf_nat_sip NAT helper.
And because each of them is exported there is quite some overhead
introduced due of this.
By introducing nf_nat_sip_hooks I am able to reduce both text/data
somewhat. For nf_conntrack_sip e. g. I get
text data bss dec
old 15243 5256 32 20531
new 15010 5192 32 20234
Signed-off-by: Holger Eitzenberger <holger@eitzenberger.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Use proper net struct to allocate skb, otherwise
netlink mmap will be of no effect.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Use proper net struct to allocate skb, otherwise netlink mmap
will have no effect.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This adds a new set that provides similar functionality to ip,port,net
but permits arbitrary size subnets for both the first and last
parameter.
Signed-off-by: Oliver Smith <oliver@8.c.9.b.0.7.4.0.1.0.0.2.ip6.arpa>
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
This patch adds netns support for ipset.
Major changes were made in ip_set_core.c and ip_set.h.
Global variables are moved to per net namespace.
Added initialization code and the destruction of the network namespace ipset subsystem.
In the prototypes of public functions ip_set_* added parameter "struct net*".
The remaining corrections related to the change prototypes of public functions ip_set_*.
The patch for git://git.netfilter.org/ipset.git commit 6a4ec96c0b8caac5c35474e40e319704d92ca347
Signed-off-by: Vitaly Lavrov <lve@guap.ru>
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
The new extensions require zero initialization for the new element
to be added into a slot from where another element was pushed away.
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
The destroy function must take into account that resizing doesn't
create new extensions so those cannot be destroyed at resize.
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
This provides kernel support for creating ipsets with comment support.
This does incur a penalty to flushing/destroying an ipset since all
entries are walked in order to free the allocated strings, this penalty
is of course less expensive than the operation of listing an ipset to
userspace, so for general-purpose usage the overall impact is expected
to be little to none.
Signed-off-by: Oliver Smith <oliver@8.c.9.b.0.7.4.0.1.0.0.2.ip6.arpa>
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
This provides kernel support for creating list ipsets with the comment
annotation extension.
Signed-off-by: Oliver Smith <oliver@8.c.9.b.0.7.4.0.1.0.0.2.ip6.arpa>
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
This provides kernel support for creating bitmap ipsets with comment
support.
As is the case for hashes, this incurs a penalty when flushing or
destroying the entire ipset as the entries must first be walked in order
to free the comment strings. This penalty is of course far less than the
cost of listing an ipset to userspace. Any set created without support
for comments will be flushed/destroyed as before.
Signed-off-by: Oliver Smith <oliver@8.c.9.b.0.7.4.0.1.0.0.2.ip6.arpa>
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
This adds the core support for having comments on ipset entries.
The comments are stored as standard null-terminated strings in
dynamically allocated memory after being passed to the kernel. As a
result of this, code has been added to the generic destroy function to
iterate all extensions and call that extension's destroy task if the set
has that extension activated, and if such a task is defined.
Signed-off-by: Oliver Smith <oliver@8.c.9.b.0.7.4.0.1.0.0.2.ip6.arpa>
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
This adds a new set that provides the ability to configure pairs of
subnets. A small amount of additional handling code has been added to
the generic hash header file - this code is conditionally activated by a
preprocessor definition.
Signed-off-by: Oliver Smith <oliver@8.c.9.b.0.7.4.0.1.0.0.2.ip6.arpa>
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Get rid of the structure based extensions and introduce a blob for
the extensions. Thus we can support more extension types easily.
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Default timeout and extension offsets are moved to struct set, because
all set types supports all extensions and it makes possible to generalize
extension support.
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
In order to support hash:net,net, hash:net,port,net etc. types,
arrays are introduced for the book-keeping of existing cidr sizes
and network numbers in a set.
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
ip[6]tables set match and SET target need to know the family of the set
in order to reject adding rules which refer to a set with a non-mathcing
family. Currently such rules are silently accepted and then ignored
instead of generating a clear error message to the user, which is not
helpful.
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Enable ipset port set types to match IPv4 package fragments for
protocols that doesn't have ports (or the port information isn't
supported by ipset).
For example this allows a hash:ip,port ipset containing the entry
192.168.0.1,gre:0 to match all package fragments for PPTP VPN tunnels
to/from the host. Without this patch only the first package fragment
(with fragment offset 0) was matched, while subsequent fragments wasn't.
This is not possible for IPv6, where the protocol is in the fragmented
part of the package unlike IPv4, where the protocol is in the IP header.
IPPROTO_ICMPV6 is deliberately not included, because it isn't relevant
for IPv4.
Signed-off-by: Anders K. Pedersen <akp@surftown.com>
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
net/netfilter/ipset/ip_set_hash_ipportnet.c:275:20:
warning: symbol 'cidr' shadows an earlier one
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
TCP packets hitting the SYN proxy through the SYNPROXY target are not
validated by TCP conntrack. When th->doff is below 5, an underflow happens
when calculating the options length, causing skb_header_pointer() to
return NULL and triggering the BUG_ON().
Handle this case gracefully by checking for NULL instead of using BUG_ON().
Reported-by: Martin Topholm <mph@one.com>
Tested-by: Martin Topholm <mph@one.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch refactors the code to skip tcpmss_reverse_mtu if no
clamp-mss-to-pmtu is specified.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Currently set_expected_rtp_rtcp() in the SIP helper uses
rcu_dereference() two times to access two different NAT hook
functions. However, only the first one is protected by the RCU
reader lock, but the 2nd isn't. Fix it by extending the RCU
protected area.
This is more a cosmetic thing since we rely on all netfilter hooks
being rcu_read_lock()ed by nf_hook_slow() in many places anyways,
as Patrick McHardy clarified.
Signed-off-by: Holger Eitzenberger <holger.eitzenberger@sophos.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
If local fragmentation is allowed, then ip_select_ident() and
ip_select_ident_more() need to generate unique IDs to ensure
correct defragmentation on the peer.
For example, if IPsec (tunnel mode) has to encrypt large skbs
that have local_df bit set, then all IP fragments that belonged
to different ESP datagrams would have used the same identificator.
If one of these IP fragments would get lost or reordered, then
peer could possibly stitch together wrong IP fragments that did
not belong to the same datagram. This would lead to a packet loss
or data corruption.
Signed-off-by: Ansis Atteka <aatteka@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When reading percpu stats we need to properly reset
the sum when CPU 0 is not present in the possible mask.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
commit c5549571f9 ("ipvs: convert lblcr scheduler to rcu")
allows RCU readers to use dest after calling ip_vs_dest_put().
In the corner case it can race with ip_vs_dest_trash_expire()
which can release the dest while it is being returned to the
RCU readers as scheduling result.
To fix the problem do not allow e->dest to be replaced and
defer the ip_vs_dest_put() call by using RCU callback. Now
e->dest does not need to be RCU pointer.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
commit c2a4ffb70e ("ipvs: convert lblc scheduler to rcu")
allows RCU readers to use dest after calling ip_vs_dest_put().
In the corner case it can race with ip_vs_dest_trash_expire()
which can release the dest while it is being returned to the
RCU readers as scheduling result.
To fix the problem do not allow en->dest to be replaced and
defer the ip_vs_dest_put() call by using RCU callback. Now
en->dest does not need to be RCU pointer.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
commit 578bc3ef1e ("ipvs: reorganize dest trash") added
IP_VS_DEST_STATE_REMOVING flag and RCU callback named
ip_vs_dest_wait_readers() to keep dests and services after
removal for at least a RCU grace period. But we have the
following corner cases:
- we can not reuse the same dest if its service is removed
while IP_VS_DEST_STATE_REMOVING is still set because another dest
removal in the first grace period can not extend this period.
It can happen when ipvsadm -C && ipvsadm -R is used.
- dest->svc can be replaced but ip_vs_in_stats() and
ip_vs_out_stats() have no explicit read memory barriers
when accessing dest->svc. It can happen that dest->svc
was just freed (replaced) while we use it to update
the stats.
We solve the problems as follows:
- IP_VS_DEST_STATE_REMOVING is removed and we ensure a fixed
idle period for the dest (IP_VS_DEST_TRASH_PERIOD). idle_start
will remember when for first time after deletion we noticed
dest->refcnt=0. Later, the connections can grab a reference
while in RCU grace period but if refcnt becomes 0 we can
safely free the dest and its svc.
- dest->svc becomes RCU pointer. As result, we add explicit
RCU locking in ip_vs_in_stats() and ip_vs_out_stats().
- __ip_vs_unbind_svc is renamed to __ip_vs_svc_put(), it
now can free the service immediately or after a RCU grace
period. dest->svc is not set to NULL anymore.
As result, unlinked dests and their services are
freed always after IP_VS_DEST_TRASH_PERIOD period, unused
services are freed after a RCU grace period.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Schedulers such as lblc and lblcr require the weight to be as high as the
maximum number of active connections. In commit b552f7e3a9
("ipvs: unify the formula to estimate the overhead of processing
connections"), the consideration of inactconns and activeconns was cleaned
up to always count activeconns as 256 times more important than inactconns.
In cases where 3000 or more connections are expected, a weight of 3000 *
256 * 3000 connections overflows the 32-bit signed result used to determine
if rescheduling is required.
On amd64, this merely changes the multiply and comparison instructions to
64-bit. On x86, a 64-bit result is already present from imull, so only
a few more comparison instructions are emitted.
Signed-off-by: Simon Kirby <sim@hostway.ca>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
This fixes a serious bug affecting all hash types with a net element -
specifically, if a CIDR value is deleted such that none of the same size
exist any more, all larger (less-specific) values will then fail to
match. Adding back any prefix with a CIDR equal to or more specific than
the one deleted will fix it.
Steps to reproduce:
ipset -N test hash:net
ipset -A test 1.1.0.0/16
ipset -A test 2.2.2.0/24
ipset -T test 1.1.1.1 #1.1.1.1 IS in set
ipset -D test 2.2.2.0/24
ipset -T test 1.1.1.1 #1.1.1.1 IS NOT in set
This is due to the fact that the nets counter was unconditionally
decremented prior to the iteration that shifts up the entries. Now, we
first check if there is a proceeding entry and if not, decrement it and
return. Otherwise, we proceed to iterate and then zero the last element,
which, in most cases, will already be zero.
Signed-off-by: Oliver Smith <oliver@8.c.9.b.0.7.4.0.1.0.0.2.ip6.arpa>
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
The "nomatch" commandline flag should invert the matching at testing,
similarly to the --return-nomatch flag of the "set" match of iptables.
Until now it worked with the elements with "nomatch" flag only. From
now on it works with elements without the flag too, i.e:
# ipset n test hash:net
# ipset a test 10.0.0.0/24 nomatch
# ipset t test 10.0.0.1
10.0.0.1 is NOT in set test.
# ipset t test 10.0.0.1 nomatch
10.0.0.1 is in set test.
# ipset a test 192.168.0.0/24
# ipset t test 192.168.0.1
192.168.0.1 is in set test.
# ipset t test 192.168.0.1 nomatch
192.168.0.1 is NOT in set test.
Before the patch the results were
...
# ipset t test 192.168.0.1
192.168.0.1 is in set test.
# ipset t test 192.168.0.1 nomatch
192.168.0.1 is in set test.
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
As reported by Randy Dunlap:
====================
when CONFIG_IPV6=m
and CONFIG_NETFILTER_XT_MATCH_SOCKET=y:
net/built-in.o: In function `socket_mt6_v1_v2':
xt_socket.c:(.text+0x51b55): undefined reference to `udp6_lib_lookup'
net/built-in.o: In function `socket_mt_init':
xt_socket.c:(.init.text+0x1ef8): undefined reference to `nf_defrag_ipv6_enable'
====================
Like several other modules under net/netfilter/ we have to
have a dependency "IPV6 disabled or set compatibly with this
module" clause.
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
In commit b396966c4 (netfilter: xt_TCPMSS: Fix missing fragmentation handling),
I attempted to add safe fragment handling to xt_TCPMSS. However, Andy Padavan
of Project N56U correctly points out that returning XT_CONTINUE in this
function does not work. The callers (tcpmss_tg[46]) expect to receive a value
of 0 in order to return XT_CONTINUE.
Signed-off-by: Phil Oester <kernel@linuxace.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
With CONFIG_NETFILTER_DEBUG we get the following warning during SYNPROXY init:
[ 80.558906] WARNING: CPU: 1 PID: 4833 at net/netfilter/nf_conntrack_extend.c:80 __nf_ct_ext_add_length+0x217/0x220 [nf_conntrack]()
The reason is that the conntrack template is set to confirmed before adding
the extension and it is invalid to add extensions to already confirmed
conntracks. Fix by adding the extensions before setting the conntrack to
confirmed.
Reported-by: Jesper Dangaard Brouer <jesper.brouer@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
net/netfilter/nf_conntrack_netlink.c: In function 'ctnetlink_nfqueue_attach_expect':
'helper' may be used uninitialized in this function
It was only initialized in if CTA_EXPECT_HELP_NAME attribute was
present, it must be NULL otherwise.
Problem added recently in bd077937
(netfilter: nfnetlink_queue: allow to attach expectations to conntracks).
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add a SYNPROXY for netfilter. The code is split into two parts, the synproxy
core with common functions and an address family specific target.
The SYNPROXY receives the connection request from the client, responds with
a SYN/ACK containing a SYN cookie and announcing a zero window and checks
whether the final ACK from the client contains a valid cookie.
It then establishes a connection to the original destination and, if
successful, sends a window update to the client with the window size
announced by the server.
Support for timestamps, SACK, window scaling and MSS options can be
statically configured as target parameters if the features of the server
are known. If timestamps are used, the timestamp value sent back to
the client in the SYN/ACK will be different from the real timestamp of
the server. In order to now break PAWS, the timestamps are translated in
the direction server->client.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Tested-by: Martin Topholm <mph@one.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Split out sequence number adjustments from NAT and move them to the conntrack
core to make them usable for SYN proxying. The sequence number adjustment
information is moved to a seperate extend. The extend is added to new
conntracks when a NAT mapping is set up for a connection using a helper.
As a side effect, this saves 24 bytes per connection with NAT in the common
case that a connection does not have a helper assigned.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Tested-by: Martin Topholm <mph@one.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Conflicts:
net/netfilter/nf_conntrack_proto_tcp.c
The conflict had to do with overlapping changes dealing with
fixing the use of an "s32" to hold the value returned by
NAT_OFFSET().
Pablo Neira Ayuso says:
====================
The following batch contains Netfilter/IPVS updates for your net-next tree.
More specifically, they are:
* Trivial typo fix in xt_addrtype, from Phil Oester.
* Remove net_ratelimit in the conntrack logging for consistency with other
logging subsystem, from Patrick McHardy.
* Remove unneeded includes from the recently added xt_connlabel support, from
Florian Westphal.
* Allow to update conntracks via nfqueue, don't need NFQA_CFG_F_CONNTRACK for
this, from Florian Westphal.
* Remove tproxy core, now that we have socket early demux, from Florian
Westphal.
* A couple of patches to refactor conntrack event reporting to save a good
bunch of lines, from Florian Westphal.
* Fix missing locking in NAT sequence adjustment, it did not manifested in
any known bug so far, from Patrick McHardy.
* Change sequence number adjustment variable to 32 bits, to delay the
possible early overflow in long standing connections, also from Patrick.
* Comestic cleanups for IPVS, from Dragos Foianu.
* Fix possible null dereference in IPVS in the SH scheduler, from Daniel
Borkmann.
* Allow to attach conntrack expectations via nfqueue. Before this patch, you
had to use ctnetlink instead, thus, we save the conntrack lookup.
* Export xt_rpfilter and xt_HMARK header files, from Nicolas Dichtel.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds the capability to attach expectations via nfnetlink_queue.
This is required by conntrack helpers that trigger expectations based on
the first packet seen like the TFTP and the DHCPv6 user-space helpers.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch refactors ctnetlink_create_expect by spliting it in two
chunks. As a result, we have a new function ctnetlink_alloc_expect
to allocate and to setup the expectation from ctnetlink.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Currently the conntrack checks if the ending sequence of a packet
falls within the observed receive window. However it does so even
if it has not observe any packet from the remote yet and uses an
uninitialized receive window (td_maxwin).
If a connection uses Fast Open to send a SYN-data packet which is
dropped afterward in the network. The subsequent SYNs retransmits
will all fail this check and be discarded, leading to a connection
timeout. This is because the SYN retransmit does not contain data
payload so
end == initial sequence number (isn) + 1
sender->td_end == isn + syn_data_len
receiver->td_maxwin == 0
The fix is to only apply this check after td_maxwin is initialized.
Reported-by: Michael Chan <mcfchan@stanford.edu>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Let nf_ct_delete handle delivery of the DESTROY event.
Based on earlier patch from Pablo Neira.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
skb_header_pointer could return NULL, so check for it as we do it
everywhere else in ipvs code. This fixes a coverity warning.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
These structs have a "_pad" member. Also the "phw" structs have an 8
byte "hw_addr[]" array but sometimes only the first 6 bytes are
initialized.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Fix a possible off by one access since optlen()
touches opt[offset+1] unsafely when i == tcp_hdrlen(skb) - 1.
This patch replaces tcp_hdrlen() by the local variable tcp_hdrlen
that stores the TCP header length, to save some cycles.
Reported-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Make sure the packet has enough room for the TCP header and
that it is not malformed.
While at it, store tcph->doff*4 in a variable, as it is used
several times.
This patch also fixes a possible off by one in case of malformed
TCP options.
Reported-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Get rid of the global lock and use per-conntrack locks for protecting the
sequencen number adjustment data. Additionally saves one lock/unlock
operation for every TCP packet.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Using 16 bits is too small, when many adjustments happen the offsets might
overflow and break the connection.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nf_nat_seq_adjust() needs to grab nf_nat_seqofs_lock to protect against
concurrent changes to the sequence adjustment data.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
ctnetlink contains copy-paste code from death_by_timeout. In order to
avoid changing both places in upcoming event delivery patch,
export death_by_timeout functionality and use it in the ctnetlink code.
Based on earlier patch from Pablo Neira.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We've removed nf_tproxy_core.ko, so also remove its header.
The lookup helpers are split and then moved to tproxy target/socket match.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The module was "permanent", due to the special tproxy skb->destructor.
Nowadays we have tcp early demux and its sock_edemux destructor in
networking core which can be used instead.
Thanks to early demux changes the input path now also handles
"skb->sk is tw socket" correctly, so this no longer needs the special
handling introduced with commit d503b30bd6
(netfilter: tproxy: do not assign timewait sockets to skb->sk).
Thus:
- move assign_sock function to where its needed
- don't prevent timewait sockets from being assigned to the skb
- remove nf_tproxy_core.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Allow modifying attributes of the conntrack associated with a packet
without first requesting ct data via CFG_F_CONNTRACK or extra
nfnetlink_conntrack socket.
Also remove unneded rcu_read_lock; the entire function is already
protected by rcu.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch consolidates the SCTP checksum calculation code from various
places to a single new function, sctp_compute_cksum(skb, offset).
Signed-off-by: Joe Stringer <joe@wand.net.nz>
Reviewed-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit 681f130f39 ("netfilter: xt_socket: add XT_SOCKET_NOWILDCARD
flag") added a potential NULL dereference if an old iptables package
uses v0 of the match.
Fix this by removing the test on @info in fast path.
IPv6 can remove the test as well, as it uses v1 or v2.
Reported-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nf_ct_expect_alloc leaves unset the expectation NAT fields. However,
ctnetlink_exp_dump_expect expects them to be zeroed in case they are
not used, which may not be the case. This results in dumping the NAT
tuple of the expectation when it should not.
Fix it by zeroing the NAT fields of the expectation.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Conflicts:
drivers/net/ethernet/freescale/fec_main.c
drivers/net/ethernet/renesas/sh_eth.c
net/ipv4/gre.c
The GRE conflict is between a bug fix (kfree_skb --> kfree_skb_list)
and the splitting of the gre.c code into seperate files.
The FEC conflict was two sets of changes adding ethtool support code
in an "!CONFIG_M5272" CPP protected block.
Finally the sh_eth.c conflict was between one commit add bits set
in the .eesr_err_check mask whilst another commit removed the
.tx_error_check member and assignments.
Signed-off-by: David S. Miller <davem@davemloft.net>
The common case is that TCP/IP checksums have already been
verified, e.g. by hardware (rx checksum offload), or conntrack.
Userspace can use this flag to determine when the checksum
has not been validated yet.
If the flag is set, this doesn't necessarily mean that the packet has
an invalid checksum, e.g. if NIC doesn't support rx checksum.
Userspace that sucessfully enabled NFQA_CFG_F_GSO queue feature flag can
infer that IP/TCP checksum has already been validated if either the
SKB_INFO attribute is not present or the NFQA_SKB_CSUM_NOTVERIFIED
flag is unset.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add sync_persist_mode flag to reduce sync traffic
by syncing only persistent templates.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Tested-by: Aleksey Chudov <aleksey.chudov@gmail.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
By default the SH scheduler rejects connections that are hashed onto a
realserver of weight 0. This patch adds a flag to make SH choose a
different realserver in this case, instead of rejecting the connection.
The patch also adds a flag to make SH include the source port (TCP, UDP,
SCTP) in the hash as well as the source address. This basically allows
for deterministic round-robin load balancing (i.e., where any director
in a cluster of directors with identical config will send the same
packet the same way).
The flags are service flags (IP_VS_SVC_F_SCHED*) so that these options
can be set per service. They are set using a new option to ipvsadm.
Signed-off-by: Alexander Frolkin <avf@eldamar.org.uk>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Drop SCTP connections under load (dropentry context) depending
on the protocol state, just like for TCP: INIT conns are
dropped immediately, established are dropped randomly while
connections in progress or shutdown are skipped.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Convert the SCTP state table, so that it is more readable.
Change the states to be according to the diagram in RFC 2960
and add more states suitable for middle box. Still, such
change in states adds incompatibility if systems in sync
setup include this change and others do not include it.
With this change we also have proper transitions in INPUT-ONLY
mode (DR/TUN) where we see packets only from client. Now
we should not switch to 10-second CLOSED state at a time
when we should stay in ESTABLISHED state.
The short names for states are because we have 16-char space
in ipvsadm and 11-char limit for the connection list format.
It is a sequence of the TCP implementation where the longest
state name is ESTABLISHED.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
This adds support for sloppy TCP and SCTP modes to IPVS.
When enabled (sysctls net.ipv4.vs.sloppy_tcp and
net.ipv4.vs.sloppy_sctp), allows IPVS to create connection state on any
packet, not just a TCP SYN (or SCTP INIT).
This allows connections to fail over from one IPVS director to another
mid-flight.
Signed-off-by: Alexander Frolkin <avf@eldamar.org.uk>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Before now the schedulers needed access only to IP
addresses and it was easy to get them from skb by
using ip_vs_fill_iph_addr_only.
New changes for the SH scheduler will need the protocol
and ports which is difficult to get from skb for the
IPv6 case. As we have all the data in the iph structure,
to avoid the same slow lookups provide the iph to schedulers.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Hans Schillstrom <hans@schillstrom.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
commit 0ceabd8387
(netfilter: ctnetlink: deliver labels to userspace) sets the event bit
when we raced with another packet, instead of raising the event bit
when the label bit is set for the first time.
commit 9b21f6a909
(netfilter: ctnetlink: allow userspace to modify labels) forgot to update
the event mask in the "conntrack already exists" case.
Both issues result in CTA_LABELS attribute not getting included in the
conntrack event.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
In (b20ab9c netfilter: nf_ct_helper: better logging for dropped packets)
there were some missing brackets around the logging information, thus
always returning drop.
Closes https://bugzilla.kernel.org/show_bug.cgi?id=60061
Signed-off-by: Balazs Peter Odor <balazs@obiserver.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
xt_socket module can be a nice replacement to conntrack module
in some cases (SYN filtering for example)
But it lacks the ability to match the 3rd packet of TCP
handshake (ACK coming from the client).
Add a XT_SOCKET_NOWILDCARD flag to disable the wildcard mechanism.
The wildcard is the legacy socket match behavior, that ignores
LISTEN sockets bound to INADDR_ANY (or ipv6 equivalent)
iptables -I INPUT -p tcp --syn -j SYN_CHAIN
iptables -I INPUT -m socket --nowildcard -j ACCEPT
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
When loose tracking is enabled (default), non-syn packets cause
creation of new conntracks in established state with default timeout for
established state (5 days). This causes the table to fill up with UNREPLIED
when the 'new ack' packet happened to be the last-ack of a previous,
already timed-out connection.
Consider:
A 192.168.x.52792 > 10.184.y.80: F, 426:426(0) ack 9237 win 255
B 10.184.y.80 > 192.168.x.52792: ., ack 427 win 123
<61 second pause>
C 10.184.y.80 > 192.168.x.52792: F, 9237:9237(0) ack 427 win 123
D 192.168.x.52792 > 10.184.y.80: ., ack 9238 win 255
B moves conntrack to CLOSE_WAIT and will kill it after 60 second timeout,
C is ignored (FIN set), but last packet (D) causes new ct with 5-days timeout.
Use UNACK timeout (5 minutes) instead to get rid of these entries sooner
when in ESTABLISHED state without having seen traffic in both directions.
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
These are the only calls under net/ that do not check nla_parse_nested()
for its error code, but simply continue execution. If parsing of netlink
attributes fails, we should return with an error instead of continuing.
In nearly all of these calls we have a policy attached, that is being
type verified during nla_parse_nested(), which we would miss checking
for otherwise.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Conflicts:
drivers/net/wireless/ath/ath9k/Kconfig
drivers/net/xen-netback/netback.c
net/batman-adv/bat_iv_ogm.c
net/wireless/nl80211.c
The ath9k Kconfig conflict was a change of a Kconfig option name right
next to the deletion of another option.
The xen-netback conflict was overlapping changes involving the
handling of the notify list in xen_netbk_rx_action().
Batman conflict resolution provided by Antonio Quartulli, basically
keep everything in both conflict hunks.
The nl80211 conflict is a little more involved. In 'net' we added a
dynamic memory allocation to nl80211_dump_wiphy() to fix a race that
Linus reported. Meanwhile in 'net-next' the handlers were converted
to use pre and post doit handlers which use a flag to determine
whether to hold the RTNL mutex around the operation.
However, the dump handlers to not use this logic. Instead they have
to explicitly do the locking. There were apparent bugs in the
conversion of nl80211_dump_wiphy() in that we were not dropping the
RTNL mutex in all the return paths, and it seems we very much should
be doing so. So I fixed that whilst handling the overlapping changes.
To simplify the initial returns, I take the RTNL mutex after we try
to allocate 'tb'.
Signed-off-by: David S. Miller <davem@davemloft.net>
Make sure that SCTP ports are writable when embedded in ICMP
from client, so that ip_vs_nat_icmp can translate them safely.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Reduce the uses of this unnecessary typedef.
Done via perl script:
$ git grep --name-only -w ctl_table net | \
xargs perl -p -i -e '\
sub trim { my ($local) = @_; $local =~ s/(^\s+|\s+$)//g; return $local; } \
s/\b(?<!struct\s)ctl_table\b(\s*\*\s*|\s+\w+)/"struct ctl_table " . trim($1)/ge'
Reflow the modified lines that now exceed 80 columns.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Similar to commit bc6bcb59 ("netfilter: xt_TCPOPTSTRIP: fix
possible mangling beyond packet boundary"), add safe fragment
handling to xt_TCPMSS.
Signed-off-by: Phil Oester <kernel@linuxace.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
As a followup to commit 409b545a ("netfilter: xt_TCPMSS: Fix violation
of RFC879 in absence of MSS option"), John Heffner points out that IPv6
has a higher MTU than IPv4, and thus a higher minimum MSS. Update TCPMSS
target to account for this, and update RFC comment.
While at it, point to more recent reference RFC1122 instead of RFC879.
Signed-off-by: Phil Oester <kernel@linuxace.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
struct gnet_stats_rate_est contains u32 fields, so the bytes per second
field can wrap at 34360Mbit.
Add a new gnet_stats_rate_est64 structure to get 64bit bps/pps fields,
and switch the kernel to use this structure natively.
This structure is dumped to user space as a new attribute :
TCA_STATS_RATE_EST64
Old tc command will now display the capped bps (to 34360Mbit), instead
of wrapped values, and updated tc command will display correct
information.
Old tc command output, after patch :
eric:~# tc -s -d qd sh dev lo
qdisc pfifo 8001: root refcnt 2 limit 1000p
Sent 80868245400 bytes 1978837 pkt (dropped 0, overlimits 0 requeues 0)
rate 34360Mbit 189696pps backlog 0b 0p requeues 0
This patch carefully reorganizes "struct Qdisc" layout to get optimal
performance on SMP.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In (bc6bcb5 netfilter: xt_TCPOPTSTRIP: fix possible mangling beyond
packet boundary), the use of tcp_hdr was introduced. However, we
cannot assume that skb->transport_header is set for non-local packets.
Cc: Florian Westphal <fw@strlen.de>
Reported-by: Phil Oester <kernel@linuxace.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The entry struct has a 2 byte hole after ->port and another 4 byte
hole after ->stats.outpkts. You must have CAP_NET_ADMIN in your
namespace to hit this information leak.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Conflicts:
net/netfilter/nf_log.c
The conflict in nf_log.c is that in 'net' we added CONFIG_PROC_FS
protection around foo_proc_entry() calls to fix a build failure,
whereas in Pablo's tree a guard if() test around a call is
remove_proc_entry() was removed. Trivially resolved.
Pablo Neira Ayuso says:
====================
The following patchset contains the first batch of
Netfilter/IPVS updates for your net-next tree, they are:
* Three patches with improvements and code refactorization
for nfnetlink_queue, from Florian Westphal.
* FTP helper now parses replies without brackets, as RFC1123
recommends, from Jeff Mahoney.
* Rise a warning to tell everyone about ULOG deprecation,
NFLOG has been already in the kernel tree for long time
and supersedes the old logging over netlink stub, from
myself.
* Don't panic if we fail to load netfilter core framework,
just bail out instead, from myself.
* Add cond_resched_rcu, used by IPVS to allow rescheduling
while walking over big hashtables, from Simon Horman.
* Change type of IPVS sysctl_sync_qlen_max sysctl to avoid
possible overflow, from Zhang Yanfei.
* Use strlcpy instead of strncpy to skip zeroing of already
initialized area to write the extension names in ebtables,
from Chen Gang.
* Use already existing per-cpu notrack object from xt_CT,
from Eric Dumazet.
* Save explicit socket lookup in xt_socket now that we have
early demux, also from Eric Dumazet.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Merge 'net' bug fixes into 'net-next' as we have patches
that will build on top of them.
This merge commit includes a change from Emil Goode
(emilgoode@gmail.com) that fixes a warning that would
have been introduced by this merge. Specifically it
fixes the pingv6_ops method ipv6_chk_addr() to add a
"const" to the "struct net_device *dev" argument and
likewise update the dummy_ipv6_chk_addr() declaration.
Signed-off-by: David S. Miller <davem@davemloft.net>
The clamp-mss-to-pmtu option of the xt_TCPMSS target can cause issues
connecting to websites if there was no MSS option present in the
original SYN packet from the client. In these cases, it may add a
MSS higher than the default specified in RFC879. Fix this by never
setting a value > 536 if no MSS option was specified by the client.
This closes netfilter's bugzilla #662.
Signed-off-by: Phil Oester <kernel@linuxace.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
CAP_LEN contains the size of the network packet we're queueing to
userspace, i.e. normally it is the same as the NFQA_PAYLOAD attribute len.
Include it only in the unlikely case when NFQA_PAYLOAD is truncated due
to copy_range limitations.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
For every packet queued, we check if configured copy_range
is 0, and treat that as 'copy entire packet'.
We can move this check to the queue configuration, and can
set copy_range appropriately.
Also, convert repetitive '0xffff - NLA_HDRLEN' to a macro.
[ queue initialization still used 0xffff, although its harmless
since the initial setting is overwritten on queue config ]
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Fix broken incomplete object dumping if the list of objects does not
fit into one single netlink message.
Reported-by: Gabriel Lazar <Gabriel.Lazar@com.utcluj.ro>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Fix broken incomplete object dumping if the list of objects does not
fit into one single netlink message.
Reported-by: Gabriel Lazar <Gabriel.Lazar@com.utcluj.ro>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This corrects an regression introduced by "net: Use 16bits for *_headers
fields of struct skbuff" when NET_SKBUFF_DATA_USES_OFFSET is not set. In
that case skb->tail will be a pointer whereas skb->network_header
will be an offset from head. This is corrected by using wrappers that
ensure that calculations are always made using pointers.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reported-by: Chen Gang <gang.chen@asianux.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
kfree_rcu() requires offsetof(..., rcu_head) < 4096, which can
get violated with a sufficiently high CONFIG_IP_VS_SH_TAB_BITS.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
In dump_ipv6_packet(), the "recurse" parameter is zero only if
dumping contents of a packet embedded into an ICMPv6 error
message. Therefore we want to log packet mark if recurse is
non-zero, not when it is zero.
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
So far, only net_device * could be passed along with netdevice notifier
event. This patch provides a possibility to pass custom structure
able to provide info that event listener needs to know.
Signed-off-by: Jiri Pirko <jiri@resnulli.us>
v2->v3: fix typo on simeth
shortened dev_getter
shortened notifier_info struct name
v1->v2: fix notifier_call parameter in call_netdevice_notifier()
Signed-off-by: David S. Miller <davem@davemloft.net>
The FTP conntrack code currently only accepts the following format for
the 227 response for PASV:
227 Entering Passive Mode (148,100,81,40,31,161).
It doesn't accept the following format from an obscure server:
227 Data transfer will passively listen to 67,218,99,134,50,144
From RFC 1123:
The format of the 227 reply to a PASV command is not
well standardized. In particular, an FTP client cannot
assume that the parentheses shown on page 40 of RFC-959
will be present (and in fact, Figure 3 on page 43 omits
them). Therefore, a User-FTP program that interprets
the PASV reply must scan the reply for the first digit
of the host and port numbers.
This patch adds support for the RFC 1123 clarification by:
- Allowing a search filter to specify NUL as the terminator so that
try_number will return successfully if the array of numbers has been
filled when an unexpected character is encountered.
- Using space as the separator for the 227 reply and then scanning for
the first digit of the number sequence. The number sequence is parsed
out using the existing try_rfc959 but with a NUL terminator.
References: https://bugzilla.novell.com/show_bug.cgi?id=466279
References: http://bugzilla.netfilter.org/show_bug.cgi?id=574
Reported-by: Mark Post <mpost@novell.com>
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netfilter-devel@vger.kernel.org
Cc: netfilter@vger.kernel.org
Cc: coreteam@netfilter.org
Cc: netdev@vger.kernel.org
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Expire cached connection for new TCP/SCTP connection if real
server is down. Otherwise, IPVS uses the dead server for the
reused connection, instead of a new working one.
Signed-off-by: Grzegorz Lyczba <grzegorz.lyczba@gmail.com>
Acked-by: Hans Schillstrom <hans@schillstrom.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The portid is set to NETLINK_CB(skb).portid at create time.
The run-time check will always be false.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This member of struct netns_ipvs is calculated from nr_free_buffer_pages
so change its type to unsigned long in case of overflow. Also, type of
its related proc var sync_qlen_max and the return type of function
sysctl_sync_qlen_max() should be changed to unsigned long, too.
Besides, the type of ipvs_master_sync_state->sync_queue_len should be
changed to unsigned long accordingly.
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Julian Anastasov <ja@ssi.bg>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Simon Horman <horms@verge.net.au>
This avoids the situation where walking of a large number of connections
may prevent scheduling for a long time while also avoiding excessive
calls to rcu_read_unlock() and rcu_read_lock().
Note that in the case of !CONFIG_PREEMPT_RCU this will
add a call to cond_resched().
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Don't panic if we hit an error while adding the nf_log or pernet
netfilter support, just bail out.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Gao feng <gaofeng@cn.fujitsu.com>
Quoting https://bugzilla.netfilter.org/show_bug.cgi?id=812:
[ ip6tables -m addrtype ]
When I tried to use in the nat/PREROUTING it messes up the
routing cache even if the rule didn't matched at all.
[..]
If I remove the --limit-iface-in from the non-working scenario, so just
use the -m addrtype --dst-type LOCAL it works!
This happens when LOCAL type matching is requested with --limit-iface-in,
and the default ipv6 route is via the interface the packet we test
arrived on.
Because xt_addrtype uses ip6_route_output, the ipv6 routing implementation
creates an unwanted cached entry, and the packet won't make it to the
real/expected destination.
Silently ignoring --limit-iface-in makes the routing work but it breaks
rule matching (--dst-type LOCAL with limit-iface-in is supposed to only
match if the dst address is configured on the incoming interface;
without --limit-iface-in it will match if the address is reachable
via lo).
The test should call ipv6_chk_addr() instead. However, this would add
a link-time dependency on ipv6.
There are two possible solutions:
1) Revert the commit that moved ipt_addrtype to xt_addrtype,
and put ipv6 specific code into ip6t_addrtype.
2) add new "nf_ipv6_ops" struct to register pointers to ipv6 functions.
While the former might seem preferable, Pablo pointed out that there
are more xt modules with link-time dependeny issues regarding ipv6,
so lets go for 2).
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
With IP early demux added in linux-3.6, we perform TCP lookup in IP
layer before iptables hooks.
We can avoid doing a second lookup in xt_socket.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The percpu untracked ct are not currently used for XT_CT_NOTRACK.
xt_ct_tg_check()/xt_ct_target() provides a single ct.
Thats not optimal as the ct->ct_general.use cache line will bounce among
cpus.
Use the intended [1] thing : xt_ct_target() should select the percpu
object.
[1] Refs :
commit 5bfddbd46a ("netfilter: nf_conntrack: IPS_UNTRACKED bit")
commit b3c5163fe0 ("netfilter: nf_conntrack: per_cpu untracking")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This target assumes that tcph->doff is well-formed, that may be well
not the case. Add extra sanity checkings to avoid possible crash due
to read/write out of the real packet boundary. After this patch, the
default action on malformed TCP packets is to drop them. Moreover,
fragments are skipped.
Reported-by: Rafal Kupka <rkupka@telemetry.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Since (69b34fb netfilter: xt_LOG: add net namespace support
for xt_LOG), we hit this:
[ 4224.708977] BUG: unable to handle kernel NULL pointer dereference at 0000000000000388
[ 4224.709074] IP: [<ffffffff8147f699>] ipt_log_packet+0x29/0x270
when callling log functions from conntrack both in and out
are NULL i.e. the net pointer is invalid.
Adding struct net *net in call to nf_logfn() will secure that
there always is a vaild net ptr.
Reported as netfilter's bugzilla bug 818:
https://bugzilla.netfilter.org/show_bug.cgi?id=818
Reported-by: Ronald <ronald645@gmail.com>
Signed-off-by: Hans Schillstrom <hans@schillstrom.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch fixes the following compilation error:
net/netfilter/nf_log.c:373:38: error: 'struct netns_nf' has no member named 'proc_netfilter'
if procfs is not set.
The netns support for nf_log, nfnetlink_log and nfnetlink_queue_core
requires CONFIG_PROC_FS in the removal path of their respective
/proc interface since net->nf.proc_netfilter is undefined in that
case.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Gao feng <gaofeng@cn.fujitsu.com>
Pull VFS updates from Al Viro,
Misc cleanups all over the place, mainly wrt /proc interfaces (switch
create_proc_entry to proc_create(), get rid of the deprecated
create_proc_read_entry() in favor of using proc_create_data() and
seq_file etc).
7kloc removed.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (204 commits)
don't bother with deferred freeing of fdtables
proc: Move non-public stuff from linux/proc_fs.h to fs/proc/internal.h
proc: Make the PROC_I() and PDE() macros internal to procfs
proc: Supply a function to remove a proc entry by PDE
take cgroup_open() and cpuset_open() to fs/proc/base.c
ppc: Clean up scanlog
ppc: Clean up rtas_flash driver somewhat
hostap: proc: Use remove_proc_subtree()
drm: proc: Use remove_proc_subtree()
drm: proc: Use minor->index to label things, not PDE->name
drm: Constify drm_proc_list[]
zoran: Don't print proc_dir_entry data in debug
reiserfs: Don't access the proc_dir_entry in r_open(), r_start() r_show()
proc: Supply an accessor for getting the data from a PDE's parent
airo: Use remove_proc_subtree()
rtl8192u: Don't need to save device proc dir PDE
rtl8187se: Use a dir under /proc/net/r8180/
proc: Add proc_mkdir_data()
proc: Move some bits from linux/proc_fs.h to linux/{of.h,signal.h,tty.h}
proc: Move PDE_NET() to fs/proc/proc_net.c
...
Pull networking updates from David Miller:
"Highlights (1721 non-merge commits, this has to be a record of some
sort):
1) Add 'random' mode to team driver, from Jiri Pirko and Eric
Dumazet.
2) Make it so that any driver that supports configuration of multiple
MAC addresses can provide the forwarding database add and del
calls by providing a default implementation and hooking that up if
the driver doesn't have an explicit set of handlers. From Vlad
Yasevich.
3) Support GSO segmentation over tunnels and other encapsulating
devices such as VXLAN, from Pravin B Shelar.
4) Support L2 GRE tunnels in the flow dissector, from Michael Dalton.
5) Implement Tail Loss Probe (TLP) detection in TCP, from Nandita
Dukkipati.
6) In the PHY layer, allow supporting wake-on-lan in situations where
the PHY registers have to be written for it to be configured.
Use it to support wake-on-lan in mv643xx_eth.
From Michael Stapelberg.
7) Significantly improve firewire IPV6 support, from YOSHIFUJI
Hideaki.
8) Allow multiple packets to be sent in a single transmission using
network coding in batman-adv, from Martin Hundebøll.
9) Add support for T5 cxgb4 chips, from Santosh Rastapur.
10) Generalize the VXLAN forwarding tables so that there is more
flexibility in configurating various aspects of the endpoints.
From David Stevens.
11) Support RSS and TSO in hardware over GRE tunnels in bxn2x driver,
from Dmitry Kravkov.
12) Zero copy support in nfnelink_queue, from Eric Dumazet and Pablo
Neira Ayuso.
13) Start adding networking selftests.
14) In situations of overload on the same AF_PACKET fanout socket, or
per-cpu packet receive queue, minimize drop by distributing the
load to other cpus/fanouts. From Willem de Bruijn and Eric
Dumazet.
15) Add support for new payload offset BPF instruction, from Daniel
Borkmann.
16) Convert several drivers over to mdoule_platform_driver(), from
Sachin Kamat.
17) Provide a minimal BPF JIT image disassembler userspace tool, from
Daniel Borkmann.
18) Rewrite F-RTO implementation in TCP to match the final
specification of it in RFC4138 and RFC5682. From Yuchung Cheng.
19) Provide netlink socket diag of netlink sockets ("Yo dawg, I hear
you like netlink, so I implemented netlink dumping of netlink
sockets.") From Andrey Vagin.
20) Remove ugly passing of rtnetlink attributes into rtnl_doit
functions, from Thomas Graf.
21) Allow userspace to be able to see if a configuration change occurs
in the middle of an address or device list dump, from Nicolas
Dichtel.
22) Support RFC3168 ECN protection for ipv6 fragments, from Hannes
Frederic Sowa.
23) Increase accuracy of packet length used by packet scheduler, from
Jason Wang.
24) Beginning set of changes to make ipv4/ipv6 fragment handling more
scalable and less susceptible to overload and locking contention,
from Jesper Dangaard Brouer.
25) Get rid of using non-type-safe NLMSG_* macros and use nlmsg_*()
instead. From Hong Zhiguo.
26) Optimize route usage in IPVS by avoiding reference counting where
possible, from Julian Anastasov.
27) Convert IPVS schedulers to RCU, also from Julian Anastasov.
28) Support cpu fanouts in xt_NFQUEUE netfilter target, from Holger
Eitzenberger.
29) Network namespace support for nf_log, ebt_log, xt_LOG, ipt_ULOG,
nfnetlink_log, and nfnetlink_queue. From Gao feng.
30) Implement RFC3168 ECN protection, from Hannes Frederic Sowa.
31) Support several new r8169 chips, from Hayes Wang.
32) Support tokenized interface identifiers in ipv6, from Daniel
Borkmann.
33) Use usbnet_link_change() helper in USB net driver, from Ming Lei.
34) Add 802.1ad vlan offload support, from Patrick McHardy.
35) Support mmap() based netlink communication, also from Patrick
McHardy.
36) Support HW timestamping in mlx4 driver, from Amir Vadai.
37) Rationalize AF_PACKET packet timestamping when transmitting, from
Willem de Bruijn and Daniel Borkmann.
38) Bring parity to what's provided by /proc/net/packet socket dumping
and the info provided by netlink socket dumping of AF_PACKET
sockets. From Nicolas Dichtel.
39) Fix peeking beyond zero sized SKBs in AF_UNIX, from Benjamin
Poirier"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1722 commits)
filter: fix va_list build error
af_unix: fix a fatal race with bit fields
bnx2x: Prevent memory leak when cnic is absent
bnx2x: correct reading of speed capabilities
net: sctp: attribute printl with __printf for gcc fmt checks
netlink: kconfig: move mmap i/o into netlink kconfig
netpoll: convert mutex into a semaphore
netlink: Fix skb ref counting.
net_sched: act_ipt forward compat with xtables
mlx4_en: fix a build error on 32bit arches
Revert "bnx2x: allow nvram test to run when device is down"
bridge: avoid OOPS if root port not found
drivers: net: cpsw: fix kernel warn on cpsw irq enable
sh_eth: use random MAC address if no valid one supplied
3c509.c: call SET_NETDEV_DEV for all device types (ISA/ISAPnP/EISA)
tg3: fix to append hardware time stamping flags
unix/stream: fix peeking with an offset larger than data in queue
unix/dgram: fix peeking with an offset larger than data in queue
unix/dgram: peek beyond 0-sized skbs
openvswitch: Remove unneeded ovs_netdev_get_ifindex()
...
Conflicts:
drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c
drivers/net/ethernet/emulex/benet/be.h
include/net/tcp.h
net/mac802154/mac802154.h
Most conflicts were minor overlapping stuff.
The be2net driver brought in some fixes that added __vlan_put_tag
calls, which in net-next take an additional argument.
Signed-off-by: David S. Miller <davem@davemloft.net>
Use preferable function name which implies using a pseudo-random
number generator.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change the type of the crc32 parameter of sctp_end_cksum()
from __be32 to __u32 to reflect that fact that it is passed
to cpu_to_le32().
There are five in-tree users of sctp_end_cksum().
The following four had warnings flagged by sparse which are
no longer present with this change.
net/netfilter/ipvs/ip_vs_proto_sctp.c:sctp_nat_csum()
net/netfilter/ipvs/ip_vs_proto_sctp.c:sctp_csum_check()
net/sctp/input.c:sctp_rcv_checksum()
net/sctp/output.c:sctp_packet_transmit()
The fifth user is net/netfilter/nf_nat_proto_sctp.c:sctp_manip_pkt().
It has been updated to pass a __u32 instead of a __be32,
the value in question was already calculated in cpu byte-order.
net/netfilter/nf_nat_proto_sctp.c:sctp_manip_pkt() has also
been updated to assign the return value of sctp_end_cksum()
directly to a variable of type __le32, matching the
type of the return value. Previously the return value
was assigned to a variable of type __be32 and then that variable
was finally assigned to another variable of type __le32.
Problems flagged by sparse.
Compile and sparse tested only.
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Userspace can now indicate that it can cope with larger-than-mtu sized
packets and packets that have invalid ipv4/tcp checksums.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Once we allow userspace to receive gso/gro packets, userspace
needs to be able to determine when checksums appear to be
broken, but are not.
NFQA_SKB_CSUMNOTREADY means 'checksums will be fixed in kernel
later, pretend they are ok'.
NFQA_SKB_GSO could be used for statistics, or to determine when
packet size exceeds mtu.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
skb_gso_segment is expensive, so it would be nice if we could
avoid it in the future. However, userspace needs to be prepared
to receive larger-than-mtu-packets (which will also have incorrect
l3/l4 checksums), so we cannot simply remove it.
The plan is to add a per-queue feature flag that userspace can
set when binding the queue.
The problem is that in nf_queue, we only have a queue number,
not the queue context/configuration settings.
This patch should have no impact other than the skb_gso_segment
call now being in a function that has access to the queue config
data.
A new size attribute in nf_queue_entry is needed so
nfnetlink_queue can duplicate the entry of the gso skb
when segmenting the skb while also copying the route key.
The follow up patch adds switch to disable skb_gso_segment when
queue config says so.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
required by future patch that will need to duplicate the
nf_queue_entry, bumping refcounts of the copy.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The new revision of the set match supports to match the counters
and to suppress updating the counters at matching too.
At the set:list types, the updating of the subcounters can be
suppressed as well.
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Introduce extensions to elements in the core and prepare timeout as
the first one.
This patch also modifies the em_ipset classifier to use the new
extension struct layout.
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Pablo Neira Ayuso says:
====================
The following patchset contains fixes for recently applied
Netfilter/IPVS updates to the net-next tree, most relevantly
they are:
* Fix sparse warnings introduced in the RCU conversion, from
Julian Anastasov.
* Fix wrong endianness in the size field of IPVS sync messages,
from Simon Horman.
* Fix missing if checking in nf_xfrm_me_harder, from Dan Carpenter.
* Fix off by one access in the IPVS SCTP tracking code, again from
Dan Carpenter.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This if statement was accidentally dropped in (aaa795a netfilter:
nat: propagate errors from xfrm_me_harder()) so now it returns
unconditionally.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
struct ip_vs_sync_mesg and ip_vs_sync_mesg_v0 are both sent across the wire
and used internally to store IPVS synchronisation messages.
Up until now the scheme used has been to convert the size field
to network byte order before sending a message on the wire and
convert it to host byte order when sending a message.
This patch changes that scheme to always treat the field
as being network byte order. This seems appropriate as
the structure is sent across the wire. And by consistently
treating the field has network byte order it is now possible
to take advantage of sparse to flag any future miss-use.
Acked-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Hans Schillstrom <hans@schillstrom.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
The sctp_events[] come from sch->type in set_sctp_state(). They are
between 0-255 so that means we need 256 elements in the array.
I believe that because of how the code is aligned there is normally a
hole after sctp_events[] so this patch doesn't actually change anything.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
There are two motivations for this:
1. It improves readability to my eyes
2. Using nested min() calls results in a shadowed _min1 variable,
which is a bit untidy. Sparse complained about this.
I have also replaced (size_t)64 with a variable of type size_t and value 64.
This also improves readability to my eyes.
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Some service fields are in network order:
- netmask: used once in network order and also as prefix len for IPv6
- port
Other parameters are in host order:
- struct ip_vs_flags: flags and mask moved between user and kernel only
- sync state: moved between user and kernel only
- syncid: sent over network as single octet
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
kbuild test robot reports for sparse warnings in
commits c2a4ffb70e ("ipvs: convert lblc scheduler to rcu")
and c5549571f9 ("ipvs: convert lblcr scheduler to rcu").
Fix it by removing extra __rcu annotation.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
- RCU annotations for ip_vs_info_seq_start and _stop
- __percpu for cpustats
- properly dereference svc->pe in ip_vs_genl_fill_service
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
kbuild test robot reports for sparse warnings
in commit 088339a57d ("ipvs: convert connection locking"):
net/netfilter/ipvs/ip_vs_conn.c:962:13: warning: context imbalance
in 'ip_vs_conn_array' - wrong count at exit
include/linux/rcupdate.h:326:30: warning: context imbalance in
'ip_vs_conn_seq_next' - unexpected unlock
include/linux/rcupdate.h:326:30: warning: context imbalance in
'ip_vs_conn_seq_stop' - unexpected unlock
Fix it by running ip_vs_conn_array under RCU lock
to avoid conditional locking and by adding proper RCU
annotations.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Use rcu_dereference_protected to resolve
sparse warning, found by kbuild test robot:
net/netfilter/ipvs/ip_vs_ctl.c:1464:35: warning: dereference of
noderef expression
Problem from commit 026ace060d
("ipvs: optimize dst usage for real server")
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Conflicts:
drivers/net/ethernet/emulex/benet/be_main.c
drivers/net/ethernet/intel/igb/igb_main.c
drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.c
include/net/scm.h
net/batman-adv/routing.c
net/ipv4/tcp_input.c
The e{uid,gid} --> {uid,gid} credentials fix conflicted with the
cleanup in net-next to now pass cred structs around.
The be2net driver had a bug fix in 'net' that overlapped with the VLAN
interface changes by Patrick McHardy in net-next.
An IGB conflict existed because in 'net' the build_skb() support was
reverted, and in 'net-next' there was a comment style fix within that
code.
Several batman-adv conflicts were resolved by making sure that all
calls to batadv_is_my_mac() are changed to have a new bat_priv first
argument.
Eric Dumazet's TS ECR fix in TCP in 'net' conflicted with the F-RTO
rewrite in 'net-next', mostly overlapping changes.
Thanks to Stephen Rothwell and Antonio Quartulli for help with several
of these merge resolutions.
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
The following patchset contains a small batch of Netfilter
updates for your net-next tree, they are:
* Three patches that provide more accurate error reporting to
user-space, instead of -EPERM, in IPv4/IPv6 netfilter re-routing
code and NAT, from Patrick McHardy.
* Update copyright statements in Netfilter filters of
Patrick McHardy, from himself.
* Add Kconfig dependency on the raw/mangle tables to the
rpfilter, from Florian Westphal.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Get rid of the confusing mix of pid and portid and use portid consistently
for all netlink related socket identities.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Memory mapped netlink needs to store the receiving userspace socket
when sending from the kernel to userspace. Rename 'ssk' to 'sk' to
avoid confusion.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The type when timeout support was enabled, could not list all elements,
just the first ones which could fit into one netlink message: it just
did not continue listing after the first message.
Reported-by: Yoann JUET <yoann.juet@univ-nantes.fr>
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Tested-by: Yoann JUET <yoann.juet@univ-nantes.fr>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add copyright statements to all netfilter files which have had significant
changes done by myself in the past.
Some notes:
- nf_conntrack_ecache.c was incorrectly attributed to Rusty and Netfilter
Core Team when it got split out of nf_conntrack_core.c. The copyrights
even state a date which lies six years before it was written. It was
written in 2005 by Harald and myself.
- net/ipv{4,6}/netfilter.c, net/netfitler/nf_queue.c were missing copyright
statements. I've added the copyright statement from net/netfilter/core.c,
where this code originated
- for nf_conntrack_proto_tcp.c I've also added Jozsef, since I didn't want
it to give the wrong impression
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
following oops was reported:
RIP: 0010:[<ffffffffa03227f2>] [<ffffffffa03227f2>] nf_nat_cleanup_conntrack+0x42/0x70 [nf_nat]
RSP: 0018:ffff880202c63d40 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8801ac7bec28 RCX: ffff8801d0eedbe0
RDX: dead000000200200 RSI: 0000000000000011 RDI: ffffffffa03265b8
[..]
Call Trace:
[..]
[<ffffffffa02febed>] destroy_conntrack+0xbd/0x110 [nf_conntrack]
Happens when a conntrack timeout expires right after first part
of the nat cleanup has completed (bysrc hash removal), but before
part 2 has completed (re-initialization of nat area).
[ destroy callback tries to delete bysrc again ]
Patrick suggested to just remove the affected conntracks -- the
connections won't work properly anyway without nat transformation.
So, lets do that.
Reported-by: CAI Qian <caiqian@redhat.com>
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
If a resize is triggered the nomatch flag is not excluded at hashing,
which leads to the element missed at lookup in the resized set.
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The last element can be replaced or pushed off and in both
cases the reference counter must be updated.
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The only part of proc_dir_entry the code outside of fs/proc
really cares about is PDE(inode)->data. Provide a helper
for that; static inline for now, eventually will be moved
to fs/proc, along with the knowledge of struct proc_dir_entry
layout.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Propagate errors from ip_xfrm_me_harder() instead of returning EPERM in
all cases.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Conflicts:
drivers/nfc/microread/mei.c
net/netfilter/nfnetlink_queue_core.c
Pull in 'net' to get Eric Biederman's AF_UNIX fix, upon which
some cleanups are going to go on-top.
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
The following patchset contains Netfilter and IPVS updates for
your net-next tree, most relevantly they are:
* Add net namespace support to NFLOG, ULOG and ebt_ulog and NFQUEUE.
The LOG and ebt_log target has been also adapted, but they still
depend on the syslog netnamespace that seems to be missing, from
Gao Feng.
* Don't lose indications of congestion in IPv6 fragmentation handling,
from Hannes Frederic Sowa.i
* IPVS conversion to use RCU, including some code consolidation patches
and optimizations, also some from Julian Anastasov.
* cpu fanout support for NFQUEUE, from Holger Eitzenberger.
* Better error reporting to userspace when dropping packets from
all our _*_[xfrm|route]_me_harder functions, from Patrick McHardy.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Some Cisco phones create huge messages that are spread over multiple packets.
After calculating the offset of the SIP body, it is validated to be within
the packet and the packet is dropped otherwise. This breaks operation of
these phones. Since connection tracking is supposed to be passive, just let
those packets pass unmodified and untracked.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Now that this supports net namespace for nflog and nfqueue,
we can remove the global proc_net_netfilter which has no
clients anymore.
Based on patch from Gao feng.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch makes /proc/net/netfilter/nfnetlink_queue pernet.
Moreover, there's a pernet instance table and lock.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
After this patch, all nf_loggers support net namespace. Still
xt_LOG and ebt_log require syslog netns support.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch makes /proc/net/netfilter/nfnetlink_log pernet.
Moreover, there's a pernet instance table and lock.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add pernet support to xt_LOG by means of the new nf_log_set
function added in (30e0c6a netfilter: nf_log: prepare net
namespace support for loggers).
Since syslog ns has yet not been implemented, we don't want
the containers to DDOS host's syslogd. So only enable ebt_log
only from init_net and wait for syslog ns support
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch adds netns support to nf_log and it prepares netns
support for existing loggers. It is composed of four major
changes.
1) nf_log_register has been split to two functions: nf_log_register
and nf_log_set. The new nf_log_register is used to globally
register the nf_logger and nf_log_set is used for enabling
pernet support from nf_loggers.
Per netns is not yet complete after this patch, it comes in
separate follow up patches.
2) Add net as a parameter of nf_log_bind_pf. Per netns is not
yet complete after this patch, it only allows to bind the
nf_logger to the protocol family from init_net and it skips
other cases.
3) Adapt all nf_log_packet callers to pass netns as parameter.
After this patch, this function only works for init_net.
4) Make the sysctl net/netfilter/nf_log pernet.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch makes this proc dentry pernet. So far only init_net
had a /proc/net/netfilter directory.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Because rev1 and rev3 of the target share the same hashing
generalize it by introduing nfqueue_hash().
Signed-off-by: Holger Eitzenberger <holger@eitzenberger.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Current NFQUEUE target uses a hash, computed over source and
destination address (and other parameters), for steering the packet
to the actual NFQUEUE. This, however forgets about the fact that the
packet eventually is handled by a particular CPU on user request.
If E. g.
1) IRQ affinity is used to handle packets on a particular CPU already
(both single-queue or multi-queue case)
and/or
2) RPS is used to steer packets to a specific softirq
the target easily chooses an NFQUEUE which is not handled by a process
pinned to the same CPU.
The idea is therefore to use the CPU index for determining the
NFQUEUE handling the packet.
E. g. when having a system with 4 CPUs, 4 MQ queues and 4 NFQUEUEs it
looks like this:
+-----+ +-----+ +-----+ +-----+
|NFQ#0| |NFQ#1| |NFQ#2| |NFQ#3|
+-----+ +-----+ +-----+ +-----+
^ ^ ^ ^
| |NFQUEUE | |
+ + + +
+-----+ +-----+ +-----+ +-----+
|rx-0 | |rx-1 | |rx-2 | |rx-3 |
+-----+ +-----+ +-----+ +-----+
The NFQUEUEs not necessarily have to start with number 0, setups with
less NFQUEUEs than packet-handling CPUs are not a problem as well.
This patch extends the NFQUEUE target to accept a new
NFQ_FLAG_CPU_FANOUT flag. If this is specified the target uses the
CPU index for determining the NFQUEUE being used. I have to introduce
rev3 for this. The 'flags' are folded into _v2 'bypass'.
By changing the way which queue is assigned, I'm able to improve the
performance if the processes reading on the NFQUEUs are pinned
correctly.
Signed-off-by: Holger Eitzenberger <holger@eitzenberger.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We used a global BH disable in LOCAL_OUT hook.
Add _bh suffix to all places that need it and remove
the disabling from LOCAL_OUT and sync code.
Functions like ip_defrag need protection from
BH, so add it. As for nf_nat_mangle_tcp_packet, it needs
RCU lock.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
This is the final step in RCU conversion.
Things that are removed:
- svc->usecnt: now svc is accessed under RCU read lock
- svc->inc: and some unused code
- ip_vs_bind_pe and ip_vs_unbind_pe: no ability to replace PE
- __ip_vs_svc_lock: replaced with RCU
- IP_VS_WAIT_WHILE: now readers lookup svcs and dests under
RCU and work in parallel with configuration
Other changes:
- before now, a RCU read-side critical section included the
calling of the schedule method, now it is extended to include
service lookup
- ip_vs_svc_table and ip_vs_svc_fwm_table are now using hlist
- svc->pe and svc->scheduler remain to the end (of grace period),
the schedulers are prepared for such RCU readers
even after done_service is called but they need
to use synchronize_rcu because last ip_vs_scheduler_put
can happen while RCU read-side critical sections
use an outdated svc->scheduler pointer
- as planned, update_service is removed
- empty services can be freed immediately after grace period.
If dests were present, the services are freed from
the dest trash code
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
In previous commits the schedulers started to access
svc->destinations with _rcu list traversal primitives
because the IP_VS_WAIT_WHILE macro still plays the role of
grace period. Now it is time to finish the updating part,
i.e. adding and deleting of dests with _rcu suffix before
removing the IP_VS_WAIT_WHILE in next commit.
We use the same rule for conns as for the
schedulers: dests can be searched in RCU read-side critical
section where ip_vs_dest_hold can be called by ip_vs_bind_dest.
Some things are not perfect, for example, calling
functions like ip_vs_lookup_dest from updating code under
RCU, just because we use some function both from reader
and from updater.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
This method releases the scheduler state,
it can not fail. Such change will help to properly
replace the scheduler in following patch.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
All dests will go to trash, no exceptions.
But we have to use new list node t_list for this, due
to RCU changes in following patches. Dests will wait there
initial grace period and later all conns and schedulers to
put their reference. The dests don't get reference for
staying in dest trash as before.
As result, we do not load ip_vs_dest_put with
extra checks for last refcnt and the schedulers do not
need to play games with atomic_inc_not_zero while
selecting best destination.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
