Conflicts:
drivers/infiniband/hw/cxgb4/device.c
The cxgb4 conflict was simply overlapping changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
Netfilter updates for net-next
The following patchset contains updates for your net-next tree,
they are:
1) Use kvfree() helper function from x_tables, from Eric Dumazet.
2) Remove extra timer from the conntrack ecache extension, use a
workqueue instead to redeliver lost events to userspace instead,
from Florian Westphal.
3) Removal of the ulog targets for ebtables and iptables. The nflog
infrastructure superseded this almost 9 years ago, time to get rid
of this code.
4) Replace the list of loggers by an array now that we can only have
two possible non-overlapping logger flavours, ie. kernel ring buffer
and netlink logging.
5) Move Eric Dumazet's log buffer code to nf_log to reuse it from
all of the supported per-family loggers.
6) Consolidate nf_log_packet() as an unified interface for packet logging.
After this patch, if the struct nf_loginfo is available, it explicitly
selects the logger that is used.
7) Move ip and ip6 logging code from xt_LOG to the corresponding
per-family loggers. Thus, x_tables and nf_tables share the same code
for packet logging.
8) Add generic ARP packet logger, which is used by nf_tables. The
format aims to be consistent with the output of xt_LOG.
9) Add generic bridge packet logger. Again, this is used by nf_tables
and it routes the packets to the real family loggers. As a result,
we get consistent logging format for the bridge family. The ebt_log
logging code has been intentionally left in place not to break
backward compatibility since the logging output differs from xt_LOG.
10) Update nft_log to explicitly request the required family logger when
needed.
11) Finish nft_log so it supports arp, ip, ip6, bridge and inet families.
Allowing selection between netlink and kernel buffer ring logging.
12) Several fixes coming after the netfilter core logging changes spotted
by robots.
13) Use IS_ENABLED() macros whenever possible in the netfilter tree,
from Duan Jiong.
14) Removal of a couple of unnecessary branch before kfree, from Fabian
Frederick.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This code section cannot compile as it refer to non existing variable
It also pre-date git history.
Signed-off-by: Yannick Brosseau <scientist@fb.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Fix checkpatch warning:
WARNING: kfree(NULL) is safe this check is probably not required
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Simon Horman <horms@verge.net.au>
commit 8f4e0a1868 ("IPVS netns exit causes crash in conntrack")
added second ip_vs_conn_drop_conntrack call instead of just adding
the needed check. As result, the first call still can cause
crash on netns exit. Remove it.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Hans Schillstrom <hans@schillstrom.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
Use generic u64_stats_sync infrastructure to get proper 64bit stats,
even on 32bit arches, at no extra cost for 64bit arches.
Without this fix, 32bit arches can have some wrong counters at the time
the carry is propagated into upper word.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
An updater may interfer with the dumping of any of the object lists.
Fix this by using a per-net generation counter and use the
nl_dump_check_consistent() interface so the NLM_F_DUMP_INTR flag is set
to notify userspace that it has to restart the dump since an updater
has interfered.
This patch also replaces the existing consistency checking code in the
rule dumping path since it is broken. Basically, the value that the
dump callback returns is not propagated to userspace via
netlink_dump_start().
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The dump operation through netlink is not protected by the nfnl_lock.
Thus, a reader process can be dumping any of the existing object
lists while another process can be updating the list content.
This patch resolves this situation by protecting all the object
lists with RCU in the netlink dump path which is the reader side.
The updater path is already protected via nfnl_lock, so use list
manipulation RCU-safe operations.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Skip transaction handling for table updates with no changes in
the flags. This fixes a crash when passing the table flag with all
bits unset.
Reported-by: Ana Rey <anarey@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
net/netfilter/xt_LOG.c: In function 'log_tg':
>> net/netfilter/xt_LOG.c:43: error: format not a string literal and no format arguments
Fixes: fab4085 ("netfilter: log: nf_log_packet() as real unified interface")
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Use the unified nf_log_packet() interface that allows us explicit
logger selection through the nf_loginfo structure.
If you specify the group attribute, this means you want to receive
logging messages through nfnetlink_log. In that case, the snaplen
and qthreshold attributes allows you to tune internal aspects of
the netlink logging infrastructure.
On the other hand, if the level is specified, then the plain text
format through the kernel logging ring is used instead, which is
also used by default if neither group nor level are indicated.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This includes the special handling for NFPROTO_INET. There is
no real inet logger since we don't see packets of this family.
However, rules are loaded using this special family type. So
let's just request both IPV4 and IPV6 loggers.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This adds the generic plain text packet loggger for bridged packets.
It routes the logging message to the real protocol packet logger.
I decided not to refactor the ebt_log code for two reasons:
1) The ebt_log output is not consistent with the IPv4 and IPv6
Netfilter packet loggers. The output is different for no good
reason and it adds redundant code to handle packet logging.
2) To avoid breaking backward compatibility for applications
outthere that are parsing the specific ebt_log output, the ebt_log
output has been left as is. So only nftables will use the new
consistent logging format for logged bridged packets.
More decisions coming in this patch:
1) This also removes ebt_log as default logger for bridged packets.
Thus, nf_log_packet() routes packet to this new packet logger
instead. This doesn't break backward compatibility since
nf_log_packet() is not used to log packets in plain text format
from anywhere in the ebtables/netfilter bridge code.
2) The new bridge packet logger also performs a lazy request to
register the real IPv4, ARP and IPv6 netfilter packet loggers.
If the real protocol logger is no available (not compiled or the
module is not available in the system, not packet logging happens.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Before this patch, the nf_loginfo parameter specified the logging
configuration in case the specified default logger was loaded. This
patch updates the semantics of the nf_loginfo parameter in
nf_log_packet() which now indicates the logger that you explicitly
want to use.
Thus, nf_log_packet() is exposed as an unified interface which
internally routes the log message to the corresponding logger type
by family.
The module dependencies are expressed by the new nf_logger_find_get()
and nf_logger_put() functions which bump the logger module refcount.
Thus, you can not remove logger modules that are used by rules anymore.
Another important effect of this change is that the family specific
module is only loaded when required. Therefore, xt_LOG and nft_log
will just trigger the autoload of the nf_log_{ip,ip6} modules
according to the family.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The plain text logging is currently embedded into the xt_LOG target.
In order to be able to use the plain text logging from nft_log, as a
first step, this patch moves the family specific code to the following
files and Kconfig symbols:
1) net/ipv4/netfilter/nf_log_ip.c: CONFIG_NF_LOG_IPV4
2) net/ipv6/netfilter/nf_log_ip6.c: CONFIG_NF_LOG_IPV6
3) net/netfilter/nf_log_common.c: CONFIG_NF_LOG_COMMON
These new modules will be required by xt_LOG and nft_log. This patch
is based on original patch from Arturo Borrero Gonzalez.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch moves Eric Dumazet's log buffer implementation from the
xt_log.h header file to the core net/netfilter/nf_log.c. This also
includes the renaming of the structure and functions to avoid possible
undesired namespace clashes.
This change allows us to use it from the arp and bridge packet logging
implementation in follow up patches.
Now that legacy ulog targets are not available anymore in the tree, we
can have up to two possible loggers:
1) The plain text logging via kernel logging ring.
2) The nfnetlink_log infrastructure which delivers log messages
to userspace.
This patch replaces the list of loggers by an array of two pointers
per family for each possible logger and it also introduces a new field
to the nf_logger structure which indicates the position in the logger
array (based on the logger type).
This prepares a follow up patch that consolidates the nf_log_packet()
interface by allowing to specify the logger as parameter.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This brings the (per-conntrack) ecache extension back to 24 bytes in size
(was 152 byte on x86_64 with lockdep on).
When event delivery fails, re-delivery is attempted via work queue.
Redelivery is attempted at least every 0.1 seconds, but can happen
more frequently if userspace is not congested.
The nf_ct_release_dying_list() function is removed.
With this patch, ownership of the to-be-redelivered conntracks
(on-dying-list-with-DYING-bit not yet set) is with the work queue,
which will release the references once event is out.
Joint work with Pablo Neira Ayuso.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
kvfree() helper can make xt_free_table_info() much cleaner.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Fix checkpatch warning:
WARNING: kfree(NULL) is safe this check is probably not required
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Quoting Samu Kallio:
Basically what's happening is, during netns cleanup,
nf_nat_net_exit gets called before ipv4_net_exit. As I understand
it, nf_nat_net_exit is supposed to kill any conntrack entries which
have NAT context (through nf_ct_iterate_cleanup), but for some
reason this doesn't happen (perhaps something else is still holding
refs to those entries?).
When ipv4_net_exit is called, conntrack entries (including those
with NAT context) are cleaned up, but the
nat_bysource hashtable is long gone - freed in nf_nat_net_exit. The
bug happens when attempting to free a conntrack entry whose NAT hash
'prev' field points to a slot in the freed hash table (head for that
bin).
We ignore conntracks with null nat bindings. But this is wrong,
as these are in bysource hash table as well.
Restore nat-cleaning for the netns-is-being-removed case.
bug:
https://bugzilla.kernel.org/show_bug.cgi?id=65191
Fixes: c2d421e171 ('netfilter: nf_nat: fix race when unloading protocol modules')
Reported-by: Samu Kallio <samu.kallio@aberdeencloud.com>
Debugged-by: Samu Kallio <samu.kallio@aberdeencloud.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Tested-by: Samu Kallio <samu.kallio@aberdeencloud.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Simon Horman says:
====================
Fix for panic due use of tot_stats estimator outside of CONFIG_SYSCTL
It has been present since v3.6.39.
====================
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Don't include port information attributes if they are unset.
Reported-by: Ana Rey <anarey@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Otherwise, the reference to external objects (eg. modules) are not
released when the rules are removed.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
In b380e5c ("netfilter: nf_tables: add message type to transactions"),
I used the wrong message type in the rule replacement case. The rule
that is replaced needs to be handled as a deleted rule.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Since 4fefee5 ("netfilter: nf_tables: allow to delete several objects
from a batch"), every new rule bumps the chain use counter. However,
this is limited to 16 bits, which means that it will overrun after
2^16 rules.
Use a u32 chain counter and check for overflows (just like we do for
table objects).
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The patch 5e94846 ("netfilter: nf_tables: add insert operation") did
not include RCU-safe list insertion when replacing rules.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
'last' keeps track of the ct that had its refcnt bumped during previous
dump cycle. Thus it must not be overwritten until end-of-function.
Another (unrelated, theoretical) issue: Don't attempt to bump refcnt of a conntrack
whose reference count is already 0. Such conntrack is being destroyed
right now, its memory is freed once we release the percpu dying spinlock.
Fixes: b7779d06 ('netfilter: conntrack: spinlock per cpu to protect special lists.')
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The dumping prematurely stops, it seems the callback argument that
indicates that all entries have been dumped is set after iterating
on the first cpu list. The dumping also may stop before the entire
per-cpu list content is also dumped.
With this patch, conntrack -L dying now shows the dying list content
again.
Fixes: b7779d06 ("netfilter: conntrack: spinlock per cpu to protect special lists.")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The tot_stats estimator is started only when CONFIG_SYSCTL
is defined. But it is stopped without checking CONFIG_SYSCTL.
Fix the crash by moving ip_vs_stop_estimator into
ip_vs_control_net_cleanup_sysctl.
The change is needed after commit 14e405461e
("IPVS: Add __ip_vs_control_{init,cleanup}_sysctl()") from 2.6.39.
Reported-by: Jet Chen <jet.chen@intel.com>
Tested-by: Jet Chen <jet.chen@intel.com>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Pull networking updates from David Miller:
1) Seccomp BPF filters can now be JIT'd, from Alexei Starovoitov.
2) Multiqueue support in xen-netback and xen-netfront, from Andrew J
Benniston.
3) Allow tweaking of aggregation settings in cdc_ncm driver, from Bjørn
Mork.
4) BPF now has a "random" opcode, from Chema Gonzalez.
5) Add more BPF documentation and improve test framework, from Daniel
Borkmann.
6) Support TCP fastopen over ipv6, from Daniel Lee.
7) Add software TSO helper functions and use them to support software
TSO in mvneta and mv643xx_eth drivers. From Ezequiel Garcia.
8) Support software TSO in fec driver too, from Nimrod Andy.
9) Add Broadcom SYSTEMPORT driver, from Florian Fainelli.
10) Handle broadcasts more gracefully over macvlan when there are large
numbers of interfaces configured, from Herbert Xu.
11) Allow more control over fwmark used for non-socket based responses,
from Lorenzo Colitti.
12) Do TCP congestion window limiting based upon measurements, from Neal
Cardwell.
13) Support busy polling in SCTP, from Neal Horman.
14) Allow RSS key to be configured via ethtool, from Venkata Duvvuru.
15) Bridge promisc mode handling improvements from Vlad Yasevich.
16) Don't use inetpeer entries to implement ID generation any more, it
performs poorly, from Eric Dumazet.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1522 commits)
rtnetlink: fix userspace API breakage for iproute2 < v3.9.0
tcp: fixing TLP's FIN recovery
net: fec: Add software TSO support
net: fec: Add Scatter/gather support
net: fec: Increase buffer descriptor entry number
net: fec: Factorize feature setting
net: fec: Enable IP header hardware checksum
net: fec: Factorize the .xmit transmit function
bridge: fix compile error when compiling without IPv6 support
bridge: fix smatch warning / potential null pointer dereference
via-rhine: fix full-duplex with autoneg disable
bnx2x: Enlarge the dorq threshold for VFs
bnx2x: Check for UNDI in uncommon branch
bnx2x: Fix 1G-baseT link
bnx2x: Fix link for KR with swapped polarity lane
sctp: Fix sk_ack_backlog wrap-around problem
net/core: Add VF link state control policy
net/fsl: xgmac_mdio is dependent on OF_MDIO
net/fsl: Make xgmac_mdio read error message useful
net_sched: drr: warn when qdisc is not work conserving
...
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Merge tag 'llvmlinux-for-v3.16' of git://git.linuxfoundation.org/llvmlinux/kernel
Pull LLVM patches from Behan Webster:
"Next set of patches to support compiling the kernel with clang.
They've been soaking in linux-next since the last merge window.
More still in the works for the next merge window..."
* tag 'llvmlinux-for-v3.16' of git://git.linuxfoundation.org/llvmlinux/kernel:
arm, unwind, LLVMLinux: Enable clang to be used for unwinding the stack
ARM: LLVMLinux: Change "extern inline" to "static inline" in glue-cache.h
all: LLVMLinux: Change DWARF flag to support gcc and clang
net: netfilter: LLVMLinux: vlais-netfilter
crypto: LLVMLinux: aligned-attribute.patch
Now that 3.15 is released, this merges the 'next' branch into 'master',
bringing us to the normal situation where my 'master' branch is the
merge window.
* accumulated work in next: (6809 commits)
ufs: sb mutex merge + mutex_destroy
powerpc: update comments for generic idle conversion
cris: update comments for generic idle conversion
idle: remove cpu_idle() forward declarations
nbd: zero from and len fields in NBD_CMD_DISCONNECT.
mm: convert some level-less printks to pr_*
MAINTAINERS: adi-buildroot-devel is moderated
MAINTAINERS: add linux-api for review of API/ABI changes
mm/kmemleak-test.c: use pr_fmt for logging
fs/dlm/debug_fs.c: replace seq_printf by seq_puts
fs/dlm/lockspace.c: convert simple_str to kstr
fs/dlm/config.c: convert simple_str to kstr
mm: mark remap_file_pages() syscall as deprecated
mm: memcontrol: remove unnecessary memcg argument from soft limit functions
mm: memcontrol: clean up memcg zoneinfo lookup
mm/memblock.c: call kmemleak directly from memblock_(alloc|free)
mm/mempool.c: update the kmemleak stack trace for mempool allocations
lib/radix-tree.c: update the kmemleak stack trace for radix tree allocations
mm: introduce kmemleak_update_trace()
mm/kmemleak.c: use %u to print ->checksum
...
Replaced non-standard C use of Variable Length Arrays In Structs (VLAIS) in
xt_repldata.h with a C99 compliant flexible array member and then calculated
offsets to the other struct members. These other members aren't referenced by
name in this code, however this patch maintains the same memory layout and
padding as was previously accomplished using VLAIS.
Had the original structure been ordered differently, with the entries VLA at
the end, then it could have been a flexible member, and this patch would have
been a lot simpler. However since the data stored in this structure is
ultimately exported to userspace, the order of this structure can't be changed.
This patch makes no attempt to change the existing behavior, merely the way in
which the current layout is accomplished using standard C99 constructs. As such
the code can now be compiled with either gcc or clang.
This version of the patch removes the trailing alignment that the VLAIS
structure would allocate in order to simplify the patch.
Author: Mark Charlebois <charlebm@gmail.com>
Signed-off-by: Mark Charlebois <charlebm@gmail.com>
Signed-off-by: Behan Webster <behanw@converseincode.com>
Signed-off-by: Vinícius Tinti <viniciustinti@gmail.com>
Pablo Neira Ayuso says:
====================
Netfilter/nf_tables fixes for net-next
This patchset contains fixes for recent updates available in your
net-next, they are:
1) Fix double memory allocation for accounting objects that results
in a leak, this slipped through with the new quota extension,
patch from Mathieu Poirier.
2) Fix broken ordering when adding set element transactions.
3) Make sure that objects are released in reverse order in the abort
path, to avoid possible use-after-free when accessing dependencies.
4) Allow to delete several objects (as long as dependencies are
fulfilled) by using one batch. This includes changes in the use
counter semantics of the nf_tables objects.
5) Fix illegal sleeping allocation from rcu callback.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
It is available since v3.15-rc5.
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
include/net/inetpeer.h
net/ipv6/output_core.c
Changes in net were fixing bugs in code removed in net-next.
Signed-off-by: David S. Miller <davem@davemloft.net>
Ideally, we would need to generate IP ID using a per destination IP
generator.
linux kernels used inet_peer cache for this purpose, but this had a huge
cost on servers disabling MTU discovery.
1) each inet_peer struct consumes 192 bytes
2) inetpeer cache uses a binary tree of inet_peer structs,
with a nominal size of ~66000 elements under load.
3) lookups in this tree are hitting a lot of cache lines, as tree depth
is about 20.
4) If server deals with many tcp flows, we have a high probability of
not finding the inet_peer, allocating a fresh one, inserting it in
the tree with same initial ip_id_count, (cf secure_ip_id())
5) We garbage collect inet_peer aggressively.
IP ID generation do not have to be 'perfect'
Goal is trying to avoid duplicates in a short period of time,
so that reassembly units have a chance to complete reassembly of
fragments belonging to one message before receiving other fragments
with a recycled ID.
We simply use an array of generators, and a Jenkin hash using the dst IP
as a key.
ipv6_select_ident() is put back into net/ipv6/ip6_output.c where it
belongs (it is only used from this file)
secure_ip_id() and secure_ipv6_id() no longer are needed.
Rename ip_select_ident_more() to ip_select_ident_segs() to avoid
unnecessary decrement/increment of the number of segments.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use GFP_ATOMIC allocations when sending removal notifications of
anonymous sets from rcu callback context. Sleeping in that context
is illegal.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Three changes to allow the deletion of several objects with dependencies
in one transaction, they are:
1) Introduce speculative counter increment/decrement that is undone in
the abort path if required, thus we avoid hitting -EBUSY when deleting
the chain. The counter updates are reverted in the abort path.
2) Increment/decrement table/chain use counter for each set/rule. We need
this to fully rely on the use counters instead of the list content,
eg. !list_empty(&chain->rules) which evaluate true in the middle of the
transaction.
3) Decrement table use counter when an anonymous set is bound to the
rule in the commit path. This avoids hitting -EBUSY when deleting
the table that contains anonymous sets. The anonymous sets are released
in the nf_tables_rule_destroy path. This should not be a problem since
the rule already bumped the use counter of the chain, so the bound
anonymous set reflects dependencies through the rule object, which
already increases the chain use counter.
So the general assumption after this patch is that the use counters are
bumped by direct object dependencies.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
There's no rbtree rcu version yet, so let's fall back on the spinlock
to protect the concurrent access of this structure both from user
(to update the set content) and kernel-space (in the packet path).
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The patch c7c32e7 ("netfilter: nf_tables: defer all object release via
rcu") indicates that we always release deleted objects in the reverse
order, but that is only needed in the abort path. These are the two
possible scenarios when releasing objects:
1) Deletion scenario in the commit path: no need to release objects in
the reverse order since userspace already ensures that dependencies are
fulfilled), ie. userspace tells us to delete rule -> ... -> rule ->
chain -> table. In this case, we have to release the objects in the
*same order* as userspace provided.
2) Deletion scenario in the abort path: we have to iterate in the reverse
order to undo what it cannot be added, ie. userspace sent us a batch
that includes: table -> chain -> rule -> ... -> rule, and that needs to
be partially undone. In this case, we have to release objects in the
reverse order to ensure that the set and chain objects point to valid
rule and table objects.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>