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2016-09-24netfilter: Remove explicit rcu_read_lock in nf_hook_slowAaron Conole1-1/+1
All of the callers of nf_hook_slow already hold the rcu_read_lock, so this cleanup removes the recursive call. This is just a cleanup, as the locking code gracefully handles this situation. Signed-off-by: Aaron Conole <aconole@bytheb.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-09-23Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-3/+3
2016-09-13netfilter: synproxy: Check oom when adding synproxy and seqadj ct extensionsGao Feng1-3/+3
When memory is exhausted, nfct_seqadj_ext_add may fail to add the synproxy and seqadj extensions. The function nf_ct_seqadj_init doesn't check if get valid seqadj pointer by the nfct_seqadj. Now drop the packet directly when fail to add seqadj extension to avoid dereference NULL pointer in nf_ct_seqadj_init from init_conntrack(). Signed-off-by: Gao Feng <fgao@ikuai8.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-09-12netfilter: conntrack: remove packet hotpath statsFlorian Westphal1-12/+2
These counters sit in hot path and do show up in perf, this is especially true for 'found' and 'searched' which get incremented for every packet processed. Information like searched=212030105 new=623431 found=333613 delete=623327 does not seem too helpful nowadays: - on busy systems found and searched will overflow every few hours (these are 32bit integers), other more busy ones every few days. - for debugging there are better methods, such as iptables' trace target, the conntrack log sysctls. Nowadays we also have perf tool. This removes packet path stat counters except those that are expected to be 0 (or close to 0) on a normal system, e.g. 'insert_failed' (race happened) or 'invalid' (proto tracker rejects). The insert stat is retained for the ctnetlink case. The found stat is retained for the tuple-is-taken check when NAT has to determine if it needs to pick a different source address. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-30netfilter: remove __nf_ct_kill_acct helperFlorian Westphal1-7/+5
After timer removal this just calls nf_ct_delete so remove the __ prefix version and make nf_ct_kill a shorthand for nf_ct_delete. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-30netfilter: conntrack: resched gc again if eviction rate is highFlorian Westphal1-0/+6
If we evicted a large fraction of the scanned conntrack entries re-schedule the next gc cycle for immediate execution. This triggers during tests where load is high, then drops to zero and many connections will be in TW/CLOSE state with < 30 second timeouts. Without this change it will take several minutes until conntrack count comes back to normal. Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-30netfilter: conntrack: add gc worker to remove timed-out entriesFlorian Westphal1-0/+76
Conntrack gc worker to evict stale entries. GC happens once every 5 seconds, but we only scan at most 1/64th of the table (and not more than 8k) buckets to avoid hogging cpu. This means that a complete scan of the table will take several minutes of wall-clock time. Considering that the gc run will never have to evict any entries during normal operation because those will happen from packet path this should be fine. We only need gc to make sure userspace (conntrack event listeners) eventually learn of the timeout, and for resource reclaim in case the system becomes idle. We do not disable BH and cond_resched for every bucket so this should not introduce noticeable latencies either. A followup patch will add a small change to speed up GC for the extreme case where most entries are timed out on an otherwise idle system. v2: Use cond_resched_rcu_qs & add comment wrt. missing restart on nulls value change in gc worker, suggested by Eric Dumazet. v3: don't call cancel_delayed_work_sync twice (again, Eric). Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-30netfilter: conntrack: get rid of conntrack timerFlorian Westphal1-41/+50
With stats enabled this eats 80 bytes on x86_64 per nf_conn entry, as Eric Dumazet pointed out during netfilter workshop 2016. Eric also says: "Another reason was the fact that Thomas was about to change max timer range [..]" (500462a9de657f8, 'timers: Switch to a non-cascading wheel'). Remove the timer and use a 32bit jiffies value containing timestamp until entry is valid. During conntrack lookup, even before doing tuple comparision, check the timeout value and evict the entry in case it is too old. The dying bit is used as a synchronization point to avoid races where multiple cpus try to evict the same entry. Because lookup is always lockless, we need to bump the refcnt once when we evict, else we could try to evict already-dead entry that is being recycled. This is the standard/expected way when conntrack entries are destroyed. Followup patches will introduce garbage colliction via work queue and further places where we can reap obsoleted entries (e.g. during netlink dumps), this is needed to avoid expired conntracks from hanging around for too long when lookup rate is low after a busy period. Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-30netfilter: restart search if moved to other chainFlorian Westphal1-0/+7
In case nf_conntrack_tuple_taken did not find a conflicting entry check that all entries in this hash slot were tested and restart in case an entry was moved to another chain. Reported-by: Eric Dumazet <edumazet@google.com> Fixes: ea781f197d6a ("netfilter: nf_conntrack: use SLAB_DESTROY_BY_RCU and get rid of call_rcu()") Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-18netfilter: nf_conntrack: restore nf_conntrack_htable_size as exported symbolPablo Neira Ayuso1-0/+2
This is required to iterate over the hash table in cttimeout, ctnetlink and nf_conntrack_ipv4. >> ERROR: "nf_conntrack_htable_size" [net/netfilter/nfnetlink_cttimeout.ko] undefined! ERROR: "nf_conntrack_htable_size" [net/netfilter/nf_conntrack_netlink.ko] undefined! ERROR: "nf_conntrack_htable_size" [net/ipv4/netfilter/nf_conntrack_ipv4.ko] undefined! Fixes: adf0516845bcd0 ("netfilter: remove ip_conntrack* sysctl compat code") Reported-by: kbuild test robot <fengguang.wu@intel.com> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-18netfilter: conntrack: simplify the code by using nf_conntrack_get_htLiping Zhang1-36/+10
Since commit 64b87639c9cb ("netfilter: conntrack: fix race between nf_conntrack proc read and hash resize") introduce the nf_conntrack_get_ht, so there's no need to check nf_conntrack_generation again and again to get the hash table and hash size. And convert nf_conntrack_get_ht to inline function here. Suggested-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-08-13netfilter: remove ip_conntrack* sysctl compat codePablo Neira Ayuso1-3/+0
This backward compatibility has been around for more than ten years, since Yasuyuki Kozakai introduced IPv6 in conntrack. These days, we have alternate /proc/net/nf_conntrack* entries, the ctnetlink interface and the conntrack utility got adopted by many people in the user community according to what I observed on the netfilter user mailing list. So let's get rid of this. Note that nf_conntrack_htable_size and unsigned int nf_conntrack_max do not need to be exported as symbol anymore. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-07-27Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds1-93/+98
Pull networking updates from David Miller: 1) Unified UDP encapsulation offload methods for drivers, from Alexander Duyck. 2) Make DSA binding more sane, from Andrew Lunn. 3) Support QCA9888 chips in ath10k, from Anilkumar Kolli. 4) Several workqueue usage cleanups, from Bhaktipriya Shridhar. 5) Add XDP (eXpress Data Path), essentially running BPF programs on RX packets as soon as the device sees them, with the option to mirror the packet on TX via the same interface. From Brenden Blanco and others. 6) Allow qdisc/class stats dumps to run lockless, from Eric Dumazet. 7) Add VLAN support to b53 and bcm_sf2, from Florian Fainelli. 8) Simplify netlink conntrack entry layout, from Florian Westphal. 9) Add ipv4 forwarding support to mlxsw spectrum driver, from Ido Schimmel, Yotam Gigi, and Jiri Pirko. 10) Add SKB array infrastructure and convert tun and macvtap over to it. From Michael S Tsirkin and Jason Wang. 11) Support qdisc packet injection in pktgen, from John Fastabend. 12) Add neighbour monitoring framework to TIPC, from Jon Paul Maloy. 13) Add NV congestion control support to TCP, from Lawrence Brakmo. 14) Add GSO support to SCTP, from Marcelo Ricardo Leitner. 15) Allow GRO and RPS to function on macsec devices, from Paolo Abeni. 16) Support MPLS over IPV4, from Simon Horman. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1622 commits) xgene: Fix build warning with ACPI disabled. be2net: perform temperature query in adapter regardless of its interface state l2tp: Correctly return -EBADF from pppol2tp_getname. net/mlx5_core/health: Remove deprecated create_singlethread_workqueue net: ipmr/ip6mr: update lastuse on entry change macsec: ensure rx_sa is set when validation is disabled tipc: dump monitor attributes tipc: add a function to get the bearer name tipc: get monitor threshold for the cluster tipc: make cluster size threshold for monitoring configurable tipc: introduce constants for tipc address validation net: neigh: disallow transition to NUD_STALE if lladdr is unchanged in neigh_update() MAINTAINERS: xgene: Add driver and documentation path Documentation: dtb: xgene: Add MDIO node dtb: xgene: Add MDIO node drivers: net: xgene: ethtool: Use phy_ethtool_gset and sset drivers: net: xgene: Use exported functions drivers: net: xgene: Enable MDIO driver drivers: net: xgene: Add backward compatibility drivers: net: phy: xgene: Add MDIO driver ...
2016-07-25Merge branch 'locking-core-for-linus' of ↵Linus Torvalds1-1/+22
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull locking updates from Ingo Molnar: "The locking tree was busier in this cycle than the usual pattern - a couple of major projects happened to coincide. The main changes are: - implement the atomic_fetch_{add,sub,and,or,xor}() API natively across all SMP architectures (Peter Zijlstra) - add atomic_fetch_{inc/dec}() as well, using the generic primitives (Davidlohr Bueso) - optimize various aspects of rwsems (Jason Low, Davidlohr Bueso, Waiman Long) - optimize smp_cond_load_acquire() on arm64 and implement LSE based atomic{,64}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}() on arm64 (Will Deacon) - introduce smp_acquire__after_ctrl_dep() and fix various barrier mis-uses and bugs (Peter Zijlstra) - after discovering ancient spin_unlock_wait() barrier bugs in its implementation and usage, strengthen its semantics and update/fix usage sites (Peter Zijlstra) - optimize mutex_trylock() fastpath (Peter Zijlstra) - ... misc fixes and cleanups" * 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (67 commits) locking/atomic: Introduce inc/dec variants for the atomic_fetch_$op() API locking/barriers, arch/arm64: Implement LDXR+WFE based smp_cond_load_acquire() locking/static_keys: Fix non static symbol Sparse warning locking/qspinlock: Use __this_cpu_dec() instead of full-blown this_cpu_dec() locking/atomic, arch/tile: Fix tilepro build locking/atomic, arch/m68k: Remove comment locking/atomic, arch/arc: Fix build locking/Documentation: Clarify limited control-dependency scope locking/atomic, arch/rwsem: Employ atomic_long_fetch_add() locking/atomic, arch/qrwlock: Employ atomic_fetch_add_acquire() locking/atomic, arch/mips: Convert to _relaxed atomics locking/atomic, arch/alpha: Convert to _relaxed atomics locking/atomic: Remove the deprecated atomic_{set,clear}_mask() functions locking/atomic: Remove linux/atomic.h:atomic_fetch_or() locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}() locking/atomic: Fix atomic64_relaxed() bits locking/atomic, arch/xtensa: Implement atomic_fetch_{add,sub,and,or,xor}() locking/atomic, arch/x86: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() locking/atomic, arch/tile: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() locking/atomic, arch/sparc: Implement atomic{,64}_fetch_{add,sub,and,or,xor}() ...
2016-07-25Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-nextDavid S. Miller1-48/+67
Pablo Neira Ayuso says: ==================== Netfilter/IPVS updates for net-next The following patchset contains Netfilter/IPVS updates for net-next, they are: 1) Count pre-established connections as active in "least connection" schedulers such that pre-established connections to avoid overloading backend servers on peak demands, from Michal Kubecek via Simon Horman. 2) Address a race condition when resizing the conntrack table by caching the bucket size when fulling iterating over the hashtable in these three possible scenarios: 1) dump via /proc/net/nf_conntrack, 2) unlinking userspace helper and 3) unlinking custom conntrack timeout. From Liping Zhang. 3) Revisit early_drop() path to perform lockless traversal on conntrack eviction under stress, use del_timer() as synchronization point to avoid two CPUs evicting the same entry, from Florian Westphal. 4) Move NAT hlist_head to nf_conn object, this simplifies the existing NAT extension and it doesn't increase size since recent patches to align nf_conn, from Florian. 5) Use rhashtable for the by-source NAT hashtable, also from Florian. 6) Don't allow --physdev-is-out from OUTPUT chain, just like --physdev-out is not either, from Hangbin Liu. 7) Automagically set on nf_conntrack counters if the user tries to match ct bytes/packets from nftables, from Liping Zhang. 8) Remove possible_net_t fields in nf_tables set objects since we just simply pass the net pointer to the backend set type implementations. 9) Fix possible off-by-one in h323, from Toby DiPasquale. 10) early_drop() may be called from ctnetlink patch, so we must hold rcu read size lock from them too, this amends Florian's patch #3 coming in this batch, from Liping Zhang. 11) Use binary search to validate jump offset in x_tables, this addresses the O(n!) validation that was introduced recently resolve security issues with unpriviledge namespaces, from Florian. 12) Fix reference leak to connlabel in error path of nft_ct, from Zhang. 13) Three updates for nft_log: Fix log prefix leak in error path. Bail out on loglevel larger than debug in nft_log and set on the new NF_LOG_F_COPY_LEN flag when snaplen is specified. Again from Zhang. 14) Allow to filter rule dumps in nf_tables based on table and chain names. 15) Simplify connlabel to always use 128 bits to store labels and get rid of unused function in xt_connlabel, from Florian. 16) Replace set_expect_timeout() by mod_timer() from the h323 conntrack helper, by Gao Feng. 17) Put back x_tables module reference in nft_compat on error, from Liping Zhang. 18) Add a reference count to the x_tables extensions cache in nft_compat, so we can remove them when unused and avoid a crash if the extensions are rmmod, again from Zhang. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-0/+8
Just several instances of overlapping changes. Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-12netfilter: conntrack: skip clash resolution if nat is in placePablo Neira Ayuso1-0/+1
The clash resolution is not easy to apply if the NAT table is registered. Even if no NAT rules are installed, the nul-binding ensures that a unique tuple is used, thus, the packet that loses race gets a different source port number, as described by: http://marc.info/?l=netfilter-devel&m=146818011604484&w=2 Clash resolution with NAT is also problematic if addresses/port range ports are used since the conntrack that wins race may describe a different mangling that we may have earlier applied to the packet via nf_nat_setup_info(). Fixes: 71d8c47fc653 ("netfilter: conntrack: introduce clash resolution on insertion race") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Tested-by: Marc Dionne <marc.c.dionne@gmail.com>
2016-07-12netfilter: conntrack: protect early_drop by rcu read lockLiping Zhang1-0/+3
User can add ct entry via nfnetlink(IPCTNL_MSG_CT_NEW), and if the total number reach the nf_conntrack_max, we will try to drop some ct entries. But in this case(the main function call path is ctnetlink_create_conntrack -> nf_conntrack_alloc -> early_drop), rcu_read_lock is not held, so race with hash resize will happen. Fixes: 242922a02717 ("netfilter: conntrack: simplify early_drop") Cc: Florian Westphal <fw@strlen.de> Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-07-11netfilter: conntrack: simplify early_dropFlorian Westphal1-48/+47
We don't need to acquire the bucket lock during early drop, we can use lockless traveral just like ____nf_conntrack_find. The timer deletion serves as synchronization point, if another cpu attempts to evict same entry, only one will succeed with timer deletion. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-07-11netfilter: conntrack: fix race between nf_conntrack proc read and hash resizeLiping Zhang1-0/+17
When we do "cat /proc/net/nf_conntrack", and meanwhile resize the conntrack hash table via /sys/module/nf_conntrack/parameters/hashsize, race will happen, because reader can observe a newly allocated hash but the old size (or vice versa). So oops will happen like follows: BUG: unable to handle kernel NULL pointer dereference at 0000000000000017 IP: [<ffffffffa0418e21>] seq_print_acct+0x11/0x50 [nf_conntrack] Call Trace: [<ffffffffa0412f4e>] ? ct_seq_show+0x14e/0x340 [nf_conntrack] [<ffffffff81261a1c>] seq_read+0x2cc/0x390 [<ffffffff812a8d62>] proc_reg_read+0x42/0x70 [<ffffffff8123bee7>] __vfs_read+0x37/0x130 [<ffffffff81347980>] ? security_file_permission+0xa0/0xc0 [<ffffffff8123cf75>] vfs_read+0x95/0x140 [<ffffffff8123e475>] SyS_read+0x55/0xc0 [<ffffffff817c2572>] entry_SYSCALL_64_fastpath+0x1a/0xa4 It is very easy to reproduce this kernel crash. 1. open one shell and input the following cmds: while : ; do echo $RANDOM > /sys/module/nf_conntrack/parameters/hashsize done 2. open more shells and input the following cmds: while : ; do cat /proc/net/nf_conntrack done 3. just wait a monent, oops will happen soon. The solution in this patch is based on Florian's Commit 5e3c61f98175 ("netfilter: conntrack: fix lookup race during hash resize"). And add a wrapper function nf_conntrack_get_ht to get hash and hsize suggested by Florian Westphal. Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-07-06Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-nextDavid S. Miller1-45/+31
Pablo Neira Ayuso says: ==================== Netfilter updates for net-next The following patchset contains Netfilter updates for net-next, they are: 1) Don't use userspace datatypes in bridge netfilter code, from Tobin Harding. 2) Iterate only once over the expectation table when removing the helper module, instead of once per-netns, from Florian Westphal. 3) Extra sanitization in xt_hook_ops_alloc() to return error in case we ever pass zero hooks, xt_hook_ops_alloc(): 4) Handle NFPROTO_INET from the logging core infrastructure, from Liping Zhang. 5) Autoload loggers when TRACE target is used from rules, this doesn't change the behaviour in case the user already selected nfnetlink_log as preferred way to print tracing logs, also from Liping Zhang. 6) Conntrack slabs with SLAB_HWCACHE_ALIGN to allow rearranging fields by cache lines, increases the size of entries in 11% per entry. From Florian Westphal. 7) Skip zone comparison if CONFIG_NF_CONNTRACK_ZONES=n, from Florian. 8) Remove useless defensive check in nf_logger_find_get() from Shivani Bhardwaj. 9) Remove zone extension as place it in the conntrack object, this is always include in the hashing and we expect more intensive use of zones since containers are in place. Also from Florian Westphal. 10) Owner match now works from any namespace, from Eric Bierdeman. 11) Make sure we only reply with TCP reset to TCP traffic from nf_reject_ipv4, patch from Liping Zhang. 12) Introduce --nflog-size to indicate amount of network packet bytes that are copied to userspace via log message, from Vishwanath Pai. This obsoletes --nflog-range that has never worked, it was designed to achieve this but it has never worked. 13) Introduce generic macros for nf_tables object generation masks. 14) Use generation mask in table, chain and set objects in nf_tables. This allows fixes interferences with ongoing preparation phase of the commit protocol and object listings going on at the same time. This update is introduced in three patches, one per object. 15) Check if the object is active in the next generation for element deactivation in the rbtree implementation, given that deactivation happens from the commit phase path we have to observe the future status of the object. 16) Support for deletion of just added elements in the hash set type. 17) Allow to resize hashtable from /proc entry, not only from the obscure /sys entry that maps to the module parameter, from Florian Westphal. 18) Get rid of NFT_BASECHAIN_DISABLED, this code is not exercised anymore since we tear down the ruleset whenever the netdevice goes away. 19) Support for matching inverted set lookups, from Arturo Borrero. 20) Simplify the iptables_mangle_hook() by removing a superfluous extra branch. 21) Introduce ether_addr_equal_masked() and use it from the netfilter codebase, from Joe Perches. 22) Remove references to "Use netfilter MARK value as routing key" from the Netfilter Kconfig description given that this toggle doesn't exists already for 10 years, from Moritz Sichert. 23) Introduce generic NF_INVF() and use it from the xtables codebase, from Joe Perches. 24) Setting logger to NONE via /proc was not working unless explicit nul-termination was included in the string. This fixes seems to leave the former behaviour there, so we don't break backward. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-01netfilter: conntrack: avoid integer overflow when resizingFlorian Westphal1-0/+7
Can overflow so we might allocate very small table when bucket count is high on a 32bit platform. Note: resize is only possible from init_netns. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-06-24netfilter: conntrack: allow increasing bucket size via sysctl tooFlorian Westphal1-13/+28
No need to restrict this to module parameter. We export a copy of the real hash size -- when user alters the value we allocate the new table, copy entries etc before we update the real size to the requested one. This is also needed because the real size is used by concurrent readers and cannot be changed without synchronizing the conntrack generation seqcnt. We only allow changing this value from the initial net namespace. Tested using http-client-benchmark vs. httpterm with concurrent while true;do echo $RANDOM > /proc/sys/net/netfilter/nf_conntrack_buckets done Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-06-23netfilter: move zone info into struct nf_connFlorian Westphal1-31/+2
Curently we store zone information as a conntrack extension. This has one drawback: for every lookup we need to fetch the zone data from the extension area. This change place the zone data directly into the main conntrack object structure and then removes the zone conntrack extension. The zone data is just 4 bytes, it fits into a padding hole before the tuplehash info, so we do not even increase the nf_conn structure size. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-06-23netfilter: conntrack: align nf_conn on cacheline boundaryFlorian Westphal1-1/+1
increases struct size by 32 bytes (288 -> 320), but it is the right thing, else any attempt to (re-)arrange nf_conn members by cacheline won't work. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-06-15netfilter: conntrack: destroy kmemcache on module removalFlorian Westphal1-0/+2
I forgot to move the kmem_cache_destroy into the exit path. Fixes: 0c5366b3a8c7 ("netfilter: conntrack: use single slab cache) Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-06-14locking/spinlock, netfilter: Fix nf_conntrack_lock() barriersPeter Zijlstra1-1/+22
Even with spin_unlock_wait() fixed, nf_conntrack_lock{,_all}() is borken as it misses a bunch of memory barriers to order the whole global vs local locks scheme. Even x86 (and other TSO archs) are affected. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> [ Updated the comments. ] Cc: Andrew Morton <akpm@linux-foundation.org> Cc: David S. Miller <davem@davemloft.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-15Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-0/+1
The nf_conntrack_core.c fix in 'net' is not relevant in 'net-next' because we no longer have a per-netns conntrack hash. The ip_gre.c conflict as well as the iwlwifi ones were cases of overlapping changes. Conflicts: drivers/net/wireless/intel/iwlwifi/mvm/tx.c net/ipv4/ip_gre.c net/netfilter/nf_conntrack_core.c Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-14nf_conntrack: avoid kernel pointer value leak in slab nameLinus Torvalds1-1/+3
The slab name ends up being visible in the directory structure under /sys, and even if you don't have access rights to the file you can see the filenames. Just use a 64-bit counter instead of the pointer to the 'net' structure to generate a unique name. This code will go away in 4.7 when the conntrack code moves to a single kmemcache, but this is the backportable simple solution to avoiding leaking kernel pointers to user space. Fixes: 5b3501faa874 ("netfilter: nf_conntrack: per netns nf_conntrack_cachep") Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Acked-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: stable@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-10netfilter: conntrack: remove uninitialized shadow variableArnd Bergmann1-1/+0
A recent commit introduced an unconditional use of an uninitialized variable, as reported in this gcc warning: net/netfilter/nf_conntrack_core.c: In function '__nf_conntrack_confirm': net/netfilter/nf_conntrack_core.c:632:33: error: 'ctinfo' may be used uninitialized in this function [-Werror=maybe-uninitialized] bytes = atomic64_read(&counter[CTINFO2DIR(ctinfo)].bytes); ^ net/netfilter/nf_conntrack_core.c:628:26: note: 'ctinfo' was declared here enum ip_conntrack_info ctinfo; The problem is that a local variable shadows the function parameter. This removes the local variable, which looks like what Pablo originally intended. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Fixes: 71d8c47fc653 ("netfilter: conntrack: introduce clash resolution on insertion race") Acked-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-09netfilter: conntrack: use single slab cacheFlorian Westphal1-22/+14
An earlier patch changed lookup side to also net_eq() namespaces after obtaining a reference on the conntrack, so a single kmemcache can be used. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-05-05netfilter: conntrack: introduce clash resolution on insertion racePablo Neira Ayuso1-3/+50
This patch introduces nf_ct_resolve_clash() to resolve race condition on conntrack insertions. This is particularly a problem for connection-less protocols such as UDP, with no initial handshake. Two or more packets may race to insert the entry resulting in packet drops. Another problematic scenario are packets enqueued to userspace via NFQUEUE after the raw table, that make it easier to trigger this race. To resolve this, the idea is to reset the conntrack entry to the one that won race. Packet and bytes counters are also merged. The 'insert_failed' stats still accounts for this situation, after this patch, the drop counter is bumped whenever we drop packets, so we can watch for unresolved clashes. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-05-05netfilter: conntrack: introduce nf_ct_acct_update()Pablo Neira Ayuso1-23/+19
Introduce a helper function to update conntrack counters. __nf_ct_kill_acct() was unnecessarily subtracting skb_network_offset() that is expected to be zero from the ipv4/ipv6 hooks. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-05-05netfilter: conntrack: __nf_ct_l4proto_find() always returns valid pointerPablo Neira Ayuso1-1/+1
Remove unnecessary check for non-nul pointer in destroy_conntrack() given that __nf_ct_l4proto_find() returns the generic protocol tracker if the protocol is not supported. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-05-05netfilter: conntrack: consider ct netns in early_drop logicFlorian Westphal1-18/+25
When iterating, skip conntrack entries living in a different netns. We could ignore netns and kill some other non-assured one, but it has two problems: - a netns can kill non-assured conntracks in other namespace - we would start to 'over-subscribe' the affected/overlimit netns. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-05-05netfilter: conntrack: use a single hashtable for all namespacesFlorian Westphal1-40/+40
We already include netns address in the hash and compare the netns pointers during lookup, so even if namespaces have overlapping addresses entries will be spread across the table. Assuming 64k bucket size, this change saves 0.5 mbyte per namespace on a 64bit system. NAT bysrc and expectation hash is still per namespace, those will changed too soon. Future patch will also make conntrack object slab cache global again. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-05-05netfilter: conntrack: make netns address part of hashFlorian Westphal1-17/+18
Once we place all conntracks into a global hash table we want them to be spread across entire hash table, even if namespaces have overlapping ip addresses. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-05-05netfilter: conntrack: check netns when comparing conntrack objectsFlorian Westphal1-10/+13
Once we place all conntracks in the same hash table we must also compare the netns pointer to skip conntracks that belong to a different namespace. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-05-05netfilter: conntrack: use nf_ct_key_equal() in more placesFlorian Westphal1-18/+11
This prepares for upcoming change that places all conntracks into a single, global table. For this to work we will need to also compare net pointer during lookup. To avoid open-coding such check use the nf_ct_key_equal helper and then later extend it to also consider net_eq. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-05-05netfilter: conntrack: don't attempt to iterate over empty tableFlorian Westphal1-0/+3
Once we place all conntracks into same table iteration becomes more costly because the table contains conntracks that we are not interested in (belonging to other netns). So don't bother scanning if the current namespace has no entries. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-05-05netfilter: conntrack: fix lookup race during hash resizeFlorian Westphal1-5/+19
When resizing the conntrack hash table at runtime via echo 42 > /sys/module/nf_conntrack/parameters/hashsize, we are racing with the conntrack lookup path -- reads can happen in parallel and nothing prevents readers from observing a the newly allocated hash but the old size (or vice versa). So access to hash[bucket] can trigger OOB read access in case the table got expanded and we saw the new size but the old hash pointer (or it got shrunk and we got new hash ptr but the size of the old and larger table): kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] SMP KASAN CPU: 0 PID: 3 Comm: ksoftirqd/0 Not tainted 4.6.0-rc2+ #107 [..] Call Trace: [<ffffffff822c3d6a>] ? nf_conntrack_tuple_taken+0x12a/0xe90 [<ffffffff822c3ac1>] ? nf_ct_invert_tuplepr+0x221/0x3a0 [<ffffffff8230e703>] get_unique_tuple+0xfb3/0x2760 Use generation counter to obtain the address/length of the same table. Also add a synchronize_net before freeing the old hash. AFAICS, without it we might access ct_hash[bucket] after ct_hash has been freed, provided that lockless reader got delayed by another event: CPU1 CPU2 seq_begin seq_retry <delay> resize occurs free oldhash for_each(oldhash[size]) Note that resize is only supported in init_netns, it took over 2 minutes of constant resizing+flooding to produce the warning, so this isn't a big problem in practice. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-05-05netfilter: conntrack: keep BH enabled during lookupFlorian Westphal1-17/+8
No need to disable BH here anymore: stats are switched to _ATOMIC variant (== this_cpu_inc()), which nowadays generates same code as the non _ATOMIC NF_STAT, at least on x86. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-04-29netfilter: conntrack: init all_locks to avoid debug warningFlorian Westphal1-1/+1
Else we get 'BUG: spinlock bad magic on CPU#' on resize when spin lock debugging is enabled. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-04-25netfilter: conntrack: use get_random_once for conntrack hash seedFlorian Westphal1-23/+3
As earlier commit removed accessed to the hash from other files we can also make it static. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-04-25netfilter: conntrack: move generation seqcnt out of netns_ctFlorian Westphal1-9/+11
We only allow rehash in init namespace, so we only use init_ns.generation. And even if we would allow it, it makes no sense as the conntrack locks are global; any ongoing rehash prevents insert/ delete. So make this private to nf_conntrack_core instead. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-03-28netfilter: nf_conntrack: Uses pr_fmt() for logging.Weongyo Jeong1-7/+8
Uses pr_fmt() macro for debugging messages of nf_conntrack module. Signed-off-by: Weongyo Jeong <weongyo.linux@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-03-15netfilter: nf_conntrack: consolidate lock/unlock into unlock_waitNicholas Mc Guire1-4/+2
The spin_lock()/spin_unlock() is synchronizing on the nf_conntrack_locks_all_lock which is equivalent to spin_unlock_wait() but the later should be more efficient. Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-02-01netfilter: conntrack: resched in nf_ct_iterate_cleanupFlorian Westphal1-0/+5
Ulrich reports soft lockup with following (shortened) callchain: NMI watchdog: BUG: soft lockup - CPU#1 stuck for 22s! __netif_receive_skb_core+0x6e4/0x774 process_backlog+0x94/0x160 net_rx_action+0x88/0x178 call_do_softirq+0x24/0x3c do_softirq+0x54/0x6c __local_bh_enable_ip+0x7c/0xbc nf_ct_iterate_cleanup+0x11c/0x22c [nf_conntrack] masq_inet_event+0x20/0x30 [nf_nat_masquerade_ipv6] atomic_notifier_call_chain+0x1c/0x2c ipv6_del_addr+0x1bc/0x220 [ipv6] Problem is that nf_ct_iterate_cleanup can run for a very long time since it can be interrupted by softirq processing. Moreover, atomic_notifier_call_chain runs with rcu readlock held. So lets call cond_resched() in nf_ct_iterate_cleanup and defer the call to a work queue for the atomic_notifier_call_chain case. We also need another cond_resched in get_next_corpse, since we have to deal with iter() always returning false, in that case get_next_corpse will walk entire conntrack table. Reported-by: Ulrich Weber <uw@ocedo.com> Tested-by: Ulrich Weber <uw@ocedo.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-01-20netfilter: nf_conntrack: use safer way to lock all bucketsSasha Levin1-10/+28
When we need to lock all buckets in the connection hashtable we'd attempt to lock 1024 spinlocks, which is way more preemption levels than supported by the kernel. Furthermore, this behavior was hidden by checking if lockdep is enabled, and if it was - use only 8 buckets(!). Fix this by using a global lock and synchronize all buckets on it when we need to lock them all. This is pretty heavyweight, but is only done when we need to resize the hashtable, and that doesn't happen often enough (or at all). Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Reviewed-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-10-12netfilter: conntrack: fix crash on timeout object removalPablo Neira Ayuso1-4/+8
The object and module refcounts are updated for each conntrack template, however, if we delete the iptables rules and we flush the timeout database, we may end up with invalid references to timeout object that are just gone. Resolve this problem by setting the timeout reference to NULL when the custom timeout entry is removed from our base. This patch requires some RCU trickery to ensure safe pointer handling. This handling is similar to what we already do with conntrack helpers, the idea is to avoid bumping the timeout object reference counter from the packet path to avoid the cost of atomic ops. Reported-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>