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2017-09-08netfilter: core: remove erroneous warn_onFlorian Westphal
kernel test robot reported: WARNING: CPU: 0 PID: 1244 at net/netfilter/core.c:218 __nf_hook_entries_try_shrink+0x49/0xcd [..] After allowing batching in nf_unregister_net_hooks its possible that an earlier call to __nf_hook_entries_try_shrink already compacted the list. If this happens we don't need to do anything. Fixes: d3ad2c17b4047 ("netfilter: core: batch nf_unregister_net_hooks synchronize_net calls") Reported-by: kernel test robot <xiaolong.ye@intel.com> Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Aaron Conole <aconole@bytheb.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-28netfilter: core: batch nf_unregister_net_hooks synchronize_net callsFlorian Westphal
re-add batching in nf_unregister_net_hooks(). Similar as before, just store an array with to-be-free'd rule arrays on stack, then call synchronize_net once per batch. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-28netfilter: debug: check for sorted arrayFlorian Westphal
Make sure our grow/shrink routine places them in the correct order. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-28netfilter: convert hook list to an arrayAaron Conole
This converts the storage and layout of netfilter hook entries from a linked list to an array. After this commit, hook entries will be stored adjacent in memory. The next pointer is no longer required. The ops pointers are stored at the end of the array as they are only used in the register/unregister path and in the legacy br_netfilter code. nf_unregister_net_hooks() is slower than needed as it just calls nf_unregister_net_hook in a loop (i.e. at least n synchronize_net() calls), this will be addressed in followup patch. Test setup: - ixgbe 10gbit - netperf UDP_STREAM, 64 byte packets - 5 hooks: (raw + mangle prerouting, mangle+filter input, inet filter): empty mangle and raw prerouting, mangle and filter input hooks: 353.9 this patch: 364.2 Signed-off-by: Aaron Conole <aconole@bytheb.org> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-07-18netfilter: fix netfilter_net_init() returnDan Carpenter
We accidentally return an uninitialized variable. Fixes: cf56c2f892a8 ("netfilter: remove old pre-netns era hook api") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-17netfilter: remove old pre-netns era hook apiFlorian Westphal
no more users in the tree, remove this. The old api is racy wrt. module removal, all users have been converted to the netns-aware api. The old api pretended we still have global hooks but that has not been true for a long time. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-05-01netfilter: nf_queue: only call synchronize_net twice if nf_queue is activeFlorian Westphal
nf_unregister_net_hook(s) can avoid a second call to synchronize_net, provided there is no nfqueue active in that net namespace (which is the common case). This also gets rid of the extra arg to nf_queue_nf_hook_drop(), normally this gets called during netns cleanup so no packets should be queued. For the rare case of base chain being unregistered or module removal while nfqueue is in use the extra hiccup due to the packet drops isn't a big deal. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-05-01netfilter: batch synchronize_net calls during hook unregisterFlorian Westphal
synchronize_net is expensive and slows down netns cleanup a lot. We have two APIs to unregister a hook: nf_unregister_net_hook (which calls synchronize_net()) and nf_unregister_net_hooks (calls nf_unregister_net_hook in a loop) Make nf_unregister_net_hook a wapper around new helper __nf_unregister_net_hook, which unlinks the hook but does not free it. Then, we can call that helper in nf_unregister_net_hooks and then call synchronize_net() only once. Andrey Konovalov reports this change improves syzkaller fuzzing speed at least twice. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-02-02netfilter: merge ctinfo into nfct pointer storage areaFlorian Westphal
After this change conntrack operations (lookup, creation, matching from ruleset) only access one instead of two sk_buff cache lines. This works for normal conntracks because those are allocated from a slab that guarantees hw cacheline or 8byte alignment (whatever is larger) so the 3 bits needed for ctinfo won't overlap with nf_conn addresses. Template allocation now does manual address alignment (see previous change) on arches that don't have sufficent kmalloc min alignment. Some spots intentionally use skb->_nfct instead of skb_nfct() helpers, this is to avoid undoing the skb_nfct() use when we remove untracked conntrack object in the future. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-12-06netfilter: convert while loops to for loopsAaron Conole
This is to facilitate converting from a singly-linked list to an array of elements. Signed-off-by: Aaron Conole <aconole@bytheb.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-12-06netfilter: introduce accessor functions for hook entriesAaron Conole
This allows easier future refactoring. Signed-off-by: Aaron Conole <aconole@bytheb.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-11-03netfilter: handle NF_REPEAT from nf_conntrack_in()Pablo Neira Ayuso
NF_REPEAT is only needed from nf_conntrack_in() under a very specific case required by the TCP protocol tracker, we can handle this case without returning to the core hook path. Handling of NF_REPEAT from the nf_reinject() is left untouched. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-11-03netfilter: merge nf_iterate() into nf_hook_slow()Pablo Neira Ayuso
nf_iterate() has become rather simple, we can integrate this code into nf_hook_slow() to reduce the amount of LOC in the core path. However, we still need nf_iterate() around for nf_queue packet handling, so move this function there where we only need it. I think it should be possible to refactor nf_queue code to get rid of it definitely, but given this is slow path anyway, let's have a look this later. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-11-03netfilter: remove hook_entries field from nf_hook_statePablo Neira Ayuso
This field is only useful for nf_queue, so store it in the nf_queue_entry structure instead, away from the core path. Pass hook_head to nf_hook_slow(). Since we always have a valid entry on the first iteration in nf_iterate(), we can use 'do { ... } while (entry)' loop instead. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-11-03netfilter: use switch() to handle verdict cases from nf_hook_slow()Pablo Neira Ayuso
Use switch() for verdict handling and add explicit handling for NF_STOLEN and other non-conventional verdicts. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-11-03netfilter: deprecate NF_STOPPablo Neira Ayuso
NF_STOP is only used by br_netfilter these days, and it can be emulated with a combination of NF_STOLEN plus explicit call to the ->okfn() function as Florian suggests. To retain binary compatibility with userspace nf_queue application, we have to keep NF_STOP around, so libnetfilter_queue userspace userspace applications still work if they use NF_STOP for some exotic reason. Out of tree modules using NF_STOP would break, but we don't care about those. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-11-03netfilter: kill NF_HOOK_THRESH() and state->treshPablo Neira Ayuso
Patch c5136b15ea36 ("netfilter: bridge: add and use br_nf_hook_thresh") introduced br_nf_hook_thresh(). Replace NF_HOOK_THRESH() by br_nf_hook_thresh from br_nf_forward_finish(), so we have no more callers for this macro. As a result, state->thresh and explicit thresh parameter in the hook state structure is not required anymore. And we can get rid of skip-hook-under-thresh loop in nf_iterate() in the core path that is only used by br_netfilter to search for the filter hook. Suggested-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-11-03netfilter: remove comments that predate rcu daysPablo Neira Ayuso
We cannot block/sleep on nf_iterate because netfilter runs under rcu read lock these days, where blocking is well-known to be illegal. So let's remove these old comments. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-11-03netfilter: get rid of useless debugging from corePablo Neira Ayuso
This patch remove compile time code to catch inconventional verdicts. We have better ways to handle this case these days, eg. pr_debug() but even though I don't think this is useful at all, so let's remove this. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-10-20netfilter: fix nf_queue handlingPablo Neira Ayuso
nf_queue handling is broken since e3b37f11e6e4 ("netfilter: replace list_head with single linked list") for two reasons: 1) If the bypass flag is set on, there are no userspace listeners and we still have more hook entries to iterate over, then jump to the next hook. Otherwise accept the packet. On nf_reinject() path, the okfn() needs to be invoked. 2) We should not re-enter the same hook on packet reinjection. If the packet is accepted, we have to skip the current hook from where the packet was enqueued, otherwise the packets gets enqueued over and over again. This restores the previous list_for_each_entry_continue() behaviour happening from nf_iterate() that was dealing with these two cases. This patch introduces a new nf_queue() wrapper function so this fix becomes simpler. Fixes: e3b37f11e6e4 ("netfilter: replace list_head with single linked list") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-10-11netfilter: Fix slab corruption.Linus Torvalds
Use the correct pattern for singly linked list insertion and deletion. We can also calculate the list head outside of the mutex. Fixes: e3b37f11e6e4 ("netfilter: replace list_head with single linked list") Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Reviewed-by: Aaron Conole <aconole@bytheb.org> Signed-off-by: David S. Miller <davem@davemloft.net> net/netfilter/core.c | 108 ++++++++++++++++----------------------------------- 1 file changed, 33 insertions(+), 75 deletions(-)
2016-09-30netfilter: accommodate different kconfig in nf_set_hooks_headAaron Conole
When CONFIG_NETFILTER_INGRESS is unset (or no), we need to handle the request for registration properly by dropping the hook. This releases the entry during the set. Fixes: e3b37f11e6e4 ("netfilter: replace list_head with single linked list") Signed-off-by: Aaron Conole <aconole@bytheb.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-09-30netfilter: Fix potential null pointer dereferenceAaron Conole
It's possible for nf_hook_entry_head to return NULL. If two nf_unregister_net_hook calls happen simultaneously with a single hook entry in the list, both will enter the nf_hook_mutex critical section. The first will successfully delete the head, but the second will see this NULL pointer and attempt to dereference. This fix ensures that no null pointer dereference could occur when such a condition happens. Fixes: e3b37f11e6e4 ("netfilter: replace list_head with single linked list") Signed-off-by: Aaron Conole <aconole@bytheb.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-09-25Merge branch 'master' of ↵Pablo Neira Ayuso
git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next Conflicts: net/netfilter/core.c net/netfilter/nf_tables_netdev.c Resolve two conflicts before pull request for David's net-next tree: 1) Between c73c24849011 ("netfilter: nf_tables_netdev: remove redundant ip_hdr assignment") from the net tree and commit ddc8b6027ad0 ("netfilter: introduce nft_set_pktinfo_{ipv4, ipv6}_validate()"). 2) Between e8bffe0cf964 ("net: Add _nf_(un)register_hooks symbols") and Aaron Conole's patches to replace list_head with single linked list. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-09-25netfilter: replace list_head with single linked listAaron Conole
The netfilter hook list never uses the prev pointer, and so can be trimmed to be a simple singly-linked list. In addition to having a more light weight structure for hook traversal, struct net becomes 5568 bytes (down from 6400) and struct net_device becomes 2176 bytes (down from 2240). Signed-off-by: Aaron Conole <aconole@bytheb.org> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-09-24netfilter: Only allow sane values in nf_register_net_hookAaron Conole
This commit adds an upfront check for sane values to be passed when registering a netfilter hook. This will be used in a future patch for a simplified hook list traversal. Signed-off-by: Aaron Conole <aconole@bytheb.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-09-24netfilter: Remove explicit rcu_read_lock in nf_hook_slowAaron Conole
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>
2016-09-19net: Add _nf_(un)register_hooks symbolsMahesh Bandewar
Add _nf_register_hooks() and _nf_unregister_hooks() calls which allow caller to hold RTNL mutex. Signed-off-by: Mahesh Bandewar <maheshb@google.com> CC: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-24Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Conflicts: net/ipv6/xfrm6_output.c net/openvswitch/flow_netlink.c net/openvswitch/vport-gre.c net/openvswitch/vport-vxlan.c net/openvswitch/vport.c net/openvswitch/vport.h The openvswitch conflicts were overlapping changes. One was the egress tunnel info fix in 'net' and the other was the vport ->send() op simplification in 'net-next'. The xfrm6_output.c conflicts was also a simplification overlapping a bug fix. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-16netfilter: make nf_queue_entry_get_refs return voidFlorian Westphal
We don't care if module is being unloaded anymore since hook unregister handling will destroy queue entries using that hook. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-10-13netfilter: sync with packet rx also after removing queue entriesFlorian Westphal
We need to sync packet rx again after flushing the queue entries. Otherwise, the following race could happen: cpu1: nf_unregister_hook(H) called, H unliked from lists, calls synchronize_net() to wait for packet rx completion. Problem is that while no new nf_queue_entry structs that use H can be allocated, another CPU might receive a verdict from userspace just before cpu1 calls nf_queue_nf_hook_drop to remove this entry: cpu2: receive verdict from userspace, lock queue cpu2: unlink nf_queue_entry struct E, which references H, from queue list cpu1: calls nf_queue_nf_hook_drop, blocks on queue spinlock cpu2: unlock queue cpu1: nf_queue_nf_hook_drop drops affected queue entries cpu2: call nf_reinject for E cpu1: kfree(H) cpu2: potential use-after-free for H Cc: Eric W. Biederman <ebiederm@xmission.com> Fixes: 085db2c04557 ("netfilter: Per network namespace netfilter hooks.") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-10-05netfilter: nfnetlink_queue: rename related to nfqueue attaching conntrack infoKen-ichirou MATSUZAWA
The idea of this series of patch is to attach conntrack information to nflog like nfqueue has already done. nfqueue conntrack info attaching basis is generic, rename those names to generic one, glue. Signed-off-by: Ken-ichirou MATSUZAWA <chamas@h4.dion.ne.jp> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-10-04netfilter: nfnetlink_queue: get rid of nfnetlink_queue_ct.cPablo Neira Ayuso
The original intention was to avoid dependencies between nfnetlink_queue and conntrack without ifdef pollution. However, we can achieve this by moving the conntrack dependent code into ctnetlink and keep some glue code to access the nfq_ct indirection from nfqueue. After this patch, the nfq_ct indirection is always compiled in the netfilter core to avoid polluting nfqueue with ifdefs. Thus, if nf_conntrack is not compiled this results in only 8-bytes of memory waste in x86_64. This patch also adds ctnetlink_nfqueue_seqadj() to avoid that the nf_conn structure layout if exposed to nf_queue, which creates another dependency with nf_conntrack at compilation time. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-18netfilter: Pass priv instead of nf_hook_ops to netfilter hooksEric W. Biederman
Only pass the void *priv parameter out of the nf_hook_ops. That is all any of the functions are interested now, and by limiting what is passed it becomes simpler to change implementation details. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-02netfilter: nf_conntrack: make nf_ct_zone_dflt built-inDaniel Borkmann
Fengguang reported, that some randconfig generated the following linker issue with nf_ct_zone_dflt object involved: [...] CC init/version.o LD init/built-in.o net/built-in.o: In function `ipv4_conntrack_defrag': nf_defrag_ipv4.c:(.text+0x93e95): undefined reference to `nf_ct_zone_dflt' net/built-in.o: In function `ipv6_defrag': nf_defrag_ipv6_hooks.c:(.text+0xe3ffe): undefined reference to `nf_ct_zone_dflt' make: *** [vmlinux] Error 1 Given that configurations exist where we have a built-in part, which is accessing nf_ct_zone_dflt such as the two handlers nf_ct_defrag_user() and nf_ct6_defrag_user(), and a part that configures nf_conntrack as a module, we must move nf_ct_zone_dflt into a fixed, guaranteed built-in area when netfilter is configured in general. Therefore, split the more generic parts into a common header under include/linux/netfilter/ and move nf_ct_zone_dflt into the built-in section that already holds parts related to CONFIG_NF_CONNTRACK in the netfilter core. This fixes the issue on my side. Fixes: 308ac9143ee2 ("netfilter: nf_conntrack: push zone object into functions") Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-28netfilter: reduce sparse warningsFlorian Westphal
bridge/netfilter/ebtables.c:290:26: warning: incorrect type in assignment (different modifiers) -> remove __pure annotation. ipv6/netfilter/ip6t_SYNPROXY.c:240:27: warning: cast from restricted __be16 -> switch ntohs to htons and vice versa. netfilter/core.c:391:30: warning: symbol 'nfq_ct_nat_hook' was not declared. Should it be static? -> delete it, got removed net/netfilter/nf_synproxy_core.c:221:48: warning: cast to restricted __be32 -> Use __be32 instead of u32. Tested with objdiff that these changes do not affect generated code. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-07-23netfilter: rename local nf_hook_list to hook_listPablo Neira Ayuso
085db2c04557 ("netfilter: Per network namespace netfilter hooks.") introduced a new nf_hook_list that is global, so let's avoid this overlap. Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-23netfilter: fix possible removal of wrong hookPablo Neira Ayuso
nf_unregister_net_hook() uses the nf_hook_ops fields as tuple to look up for the corresponding hook in the list. However, we may have two hooks with exactly the same configuration. This shouldn't be a problem for nftables since every new chain has an unique priv field set, but this may still cause us problems in the future, so better address this problem now by keeping a reference to the original nf_hook_ops structure to make sure we delete the right hook from nf_unregister_net_hook(). Fixes: 085db2c04557 ("netfilter: Per network namespace netfilter hooks.") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-23netfilter: nf_queue: fix nf_queue_nf_hook_drop()Pablo Neira Ayuso
This function reacquires the rtnl_lock() which is already held by nf_unregister_hook(). This can be triggered via: modprobe nf_conntrack_ipv4 && rmmod nf_conntrack_ipv4 [ 720.628746] INFO: task rmmod:3578 blocked for more than 120 seconds. [ 720.628749] Not tainted 4.2.0-rc2+ #113 [ 720.628752] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 720.628754] rmmod D ffff8800ca46fd58 0 3578 3571 0x00000080 [...] [ 720.628783] Call Trace: [ 720.628790] [<ffffffff8152ea0b>] schedule+0x6b/0x90 [ 720.628795] [<ffffffff8152ecb3>] schedule_preempt_disabled+0x13/0x20 [ 720.628799] [<ffffffff8152ff55>] mutex_lock_nested+0x1f5/0x380 [ 720.628803] [<ffffffff81462622>] ? rtnl_lock+0x12/0x20 [ 720.628807] [<ffffffff81462622>] ? rtnl_lock+0x12/0x20 [ 720.628812] [<ffffffff81462622>] rtnl_lock+0x12/0x20 [ 720.628817] [<ffffffff8148ab25>] nf_queue_nf_hook_drop+0x15/0x160 [ 720.628825] [<ffffffff81488d48>] nf_unregister_net_hook+0x168/0x190 [ 720.628831] [<ffffffff81488e24>] nf_unregister_hook+0x64/0x80 [ 720.628837] [<ffffffff81488e60>] nf_unregister_hooks+0x20/0x30 [...] Moreover, nf_unregister_net_hook() should only destroy the queue for this netns, not for every netns. Reported-by: Fengguang Wu <fengguang.wu@intel.com> Fixes: 085db2c04557 ("netfilter: Per network namespace netfilter hooks.") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-20netfilter: Fix memory leak in nf_register_net_hookEric W. Biederman
In the rare case that when it is a attempted to use a per network device netfilter hook and the network device does not exist the newly allocated structure can leak. Be a good citizen and free the newly allocated structure in the error handling code. Fixes: 085db2c04557 ("netfilter: Per network namespace netfilter hooks.") Reported-by: kbuild@01.org Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-07-15netfilter: move tee_active to coreFlorian Westphal
This prepares for a TEE like expression in nftables. We want to ensure only one duplicate is sent, so both will use the same percpu variable to detect duplication. The other use case is detection of recursive call to xtables, but since we don't want dependency from nft to xtables core its put into core.c instead of the x_tables core. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-07-15netfilter: Per network namespace netfilter hooks.Eric W. Biederman
- Add a new set of functions for registering and unregistering per network namespace hooks. - Modify the old global namespace hook functions to use the per network namespace hooks in their implementation, so their remains a single list that needs to be walked for any hook (this is important for keeping the hook priority working and for keeping the code walking the hooks simple). - Only allow registering the per netdevice hooks in the network namespace where the network device lives. - Dynamically allocate the structures in the per network namespace hook list in nf_register_net_hook, and unregister them in nf_unregister_net_hook. Dynamic allocate is required somewhere as the number of network namespaces are not fixed so we might as well allocate them in the registration function. The chain of registered hooks on any list is expected to be small so the cost of walking that list to find the entry we are unregistering should also be small. Performing the management of the dynamically allocated list entries in the registration and unregistration functions keeps the complexity from spreading. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2015-07-15netfilter: Factor out the hook list selection from nf_register_hookEric W. Biederman
- Add a new function find_nf_hook_list to select the nf_hook_list - Fail nf_register_hook when asked for a per netdevice hook list when support for per netdevice hook lists is not built into the kernel. - Move the hook list head selection outside of nf_hook_mutex as nothing in the selection requires the hook list, and error handling is simpler if a mutex is not held. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-07-15netfilter: Simply the tests for enabling and disabling the ingress queue hookEric W. Biederman
Replace an overcomplicated switch statement with a simple if statement. This also removes the ingress queue enable outside of nf_hook_mutex as the protection provided by the mutex is not necessary and the code is clearer having both of the static key increments together. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-06-23netfilter: nf_qeueue: Drop queue entries on nf_unregister_hookEric W. Biederman
Add code to nf_unregister_hook to flush the nf_queue when a hook is unregistered. This guarantees that the pointer that the nf_queue code retains into the nf_hook list will remain valid while a packet is queued. I tested what would happen if we do not flush queued packets and was trivially able to obtain the oops below. All that was required was to stop the nf_queue listening process, to delete all of the nf_tables, and to awaken the nf_queue listening process. > BUG: unable to handle kernel paging request at 0000000100000001 > IP: [<0000000100000001>] 0x100000001 > PGD b9c35067 PUD 0 > Oops: 0010 [#1] SMP > Modules linked in: > CPU: 0 PID: 519 Comm: lt-nfqnl_test Not tainted > task: ffff8800b9c8c050 ti: ffff8800ba9d8000 task.ti: ffff8800ba9d8000 > RIP: 0010:[<0000000100000001>] [<0000000100000001>] 0x100000001 > RSP: 0018:ffff8800ba9dba40 EFLAGS: 00010a16 > RAX: ffff8800bab48a00 RBX: ffff8800ba9dba90 RCX: ffff8800ba9dba90 > RDX: ffff8800b9c10128 RSI: ffff8800ba940900 RDI: ffff8800bab48a00 > RBP: ffff8800b9c10128 R08: ffffffff82976660 R09: ffff8800ba9dbb28 > R10: dead000000100100 R11: dead000000200200 R12: ffff8800ba940900 > R13: ffffffff8313fd50 R14: ffff8800b9c95200 R15: 0000000000000000 > FS: 00007fb91fc34700(0000) GS:ffff8800bfa00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000000100000001 CR3: 00000000babfb000 CR4: 00000000000007f0 > Stack: > ffffffff8206ab0f ffffffff82982240 ffff8800bab48a00 ffff8800b9c100a8 > ffff8800b9c10100 0000000000000001 ffff8800ba940900 ffff8800b9c10128 > ffffffff8206bd65 ffff8800bfb0d5e0 ffff8800bab48a00 0000000000014dc0 > Call Trace: > [<ffffffff8206ab0f>] ? nf_iterate+0x4f/0xa0 > [<ffffffff8206bd65>] ? nf_reinject+0x125/0x190 > [<ffffffff8206dee5>] ? nfqnl_recv_verdict+0x255/0x360 > [<ffffffff81386290>] ? nla_parse+0x80/0xf0 > [<ffffffff8206c42c>] ? nfnetlink_rcv_msg+0x13c/0x240 > [<ffffffff811b2fec>] ? __memcg_kmem_get_cache+0x4c/0x150 > [<ffffffff8206c2f0>] ? nfnl_lock+0x20/0x20 > [<ffffffff82068159>] ? netlink_rcv_skb+0xa9/0xc0 > [<ffffffff820677bf>] ? netlink_unicast+0x12f/0x1c0 > [<ffffffff82067ade>] ? netlink_sendmsg+0x28e/0x650 > [<ffffffff81fdd814>] ? sock_sendmsg+0x44/0x50 > [<ffffffff81fde07b>] ? ___sys_sendmsg+0x2ab/0x2c0 > [<ffffffff810e8f73>] ? __wake_up+0x43/0x70 > [<ffffffff8141a134>] ? tty_write+0x1c4/0x2a0 > [<ffffffff81fde9f4>] ? __sys_sendmsg+0x44/0x80 > [<ffffffff823ff8d7>] ? system_call_fastpath+0x12/0x6a > Code: Bad RIP value. > RIP [<0000000100000001>] 0x100000001 > RSP <ffff8800ba9dba40> > CR2: 0000000100000001 > ---[ end trace 08eb65d42362793f ]--- Cc: stable@vger.kernel.org Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-14netfilter: add netfilter ingress hook after handle_ing() under unique static keyPablo Neira
This patch adds the Netfilter ingress hook just after the existing tc ingress hook, that seems to be the consensus solution for this. Note that the Netfilter hook resides under the global static key that enables ingress filtering. Nonetheless, Netfilter still also has its own static key for minimal impact on the existing handle_ing(). * Without this patch: Result: OK: 6216490(c6216338+d152) usec, 100000000 (60byte,0frags) 16086246pps 7721Mb/sec (7721398080bps) errors: 100000000 42.46% kpktgend_0 [kernel.kallsyms] [k] __netif_receive_skb_core 25.92% kpktgend_0 [kernel.kallsyms] [k] kfree_skb 7.81% kpktgend_0 [pktgen] [k] pktgen_thread_worker 5.62% kpktgend_0 [kernel.kallsyms] [k] ip_rcv 2.70% kpktgend_0 [kernel.kallsyms] [k] netif_receive_skb_internal 2.34% kpktgend_0 [kernel.kallsyms] [k] netif_receive_skb_sk 1.44% kpktgend_0 [kernel.kallsyms] [k] __build_skb * With this patch: Result: OK: 6214833(c6214731+d101) usec, 100000000 (60byte,0frags) 16090536pps 7723Mb/sec (7723457280bps) errors: 100000000 41.23% kpktgend_0 [kernel.kallsyms] [k] __netif_receive_skb_core 26.57% kpktgend_0 [kernel.kallsyms] [k] kfree_skb 7.72% kpktgend_0 [pktgen] [k] pktgen_thread_worker 5.55% kpktgend_0 [kernel.kallsyms] [k] ip_rcv 2.78% kpktgend_0 [kernel.kallsyms] [k] netif_receive_skb_internal 2.06% kpktgend_0 [kernel.kallsyms] [k] netif_receive_skb_sk 1.43% kpktgend_0 [kernel.kallsyms] [k] __build_skb * Without this patch + tc ingress: tc filter add dev eth4 parent ffff: protocol ip prio 1 \ u32 match ip dst 4.3.2.1/32 Result: OK: 9269001(c9268821+d179) usec, 100000000 (60byte,0frags) 10788648pps 5178Mb/sec (5178551040bps) errors: 100000000 40.99% kpktgend_0 [kernel.kallsyms] [k] __netif_receive_skb_core 17.50% kpktgend_0 [kernel.kallsyms] [k] kfree_skb 11.77% kpktgend_0 [cls_u32] [k] u32_classify 5.62% kpktgend_0 [kernel.kallsyms] [k] tc_classify_compat 5.18% kpktgend_0 [pktgen] [k] pktgen_thread_worker 3.23% kpktgend_0 [kernel.kallsyms] [k] tc_classify 2.97% kpktgend_0 [kernel.kallsyms] [k] ip_rcv 1.83% kpktgend_0 [kernel.kallsyms] [k] netif_receive_skb_internal 1.50% kpktgend_0 [kernel.kallsyms] [k] netif_receive_skb_sk 0.99% kpktgend_0 [kernel.kallsyms] [k] __build_skb * With this patch + tc ingress: tc filter add dev eth4 parent ffff: protocol ip prio 1 \ u32 match ip dst 4.3.2.1/32 Result: OK: 9308218(c9308091+d126) usec, 100000000 (60byte,0frags) 10743194pps 5156Mb/sec (5156733120bps) errors: 100000000 42.01% kpktgend_0 [kernel.kallsyms] [k] __netif_receive_skb_core 17.78% kpktgend_0 [kernel.kallsyms] [k] kfree_skb 11.70% kpktgend_0 [cls_u32] [k] u32_classify 5.46% kpktgend_0 [kernel.kallsyms] [k] tc_classify_compat 5.16% kpktgend_0 [pktgen] [k] pktgen_thread_worker 2.98% kpktgend_0 [kernel.kallsyms] [k] ip_rcv 2.84% kpktgend_0 [kernel.kallsyms] [k] tc_classify 1.96% kpktgend_0 [kernel.kallsyms] [k] netif_receive_skb_internal 1.57% kpktgend_0 [kernel.kallsyms] [k] netif_receive_skb_sk Note that the results are very similar before and after. I can see gcc gets the code under the ingress static key out of the hot path. Then, on that cold branch, it generates the code to accomodate the netfilter ingress static key. My explanation for this is that this reduces the pressure on the instruction cache for non-users as the new code is out of the hot path, and it comes with minimal impact for tc ingress users. Using gcc version 4.8.4 on: Architecture: x86_64 CPU op-mode(s): 32-bit, 64-bit Byte Order: Little Endian CPU(s): 8 [...] L1d cache: 16K L1i cache: 64K L2 cache: 2048K L3 cache: 8192K Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Acked-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-14netfilter: add hook list to nf_hook_statePablo Neira
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-04netfilter: Make nf_hookfn use nf_hook_state.David S. Miller
Pass the nf_hook_state all the way down into the hook functions themselves. Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-04netfilter: Create and use nf_hook_state.David S. Miller
Instead of passing a large number of arguments down into the nf_hook() entry points, create a structure which carries this state down through the hook processing layers. This makes is so that if we want to change the types or signatures of any of these pieces of state, there are less places that need to be changed. Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-13netfilter: fix various sparse warningsFlorian Westphal
net/bridge/br_netfilter.c:870:6: symbol 'br_netfilter_enable' was not declared. Should it be static? no; add include net/ipv4/netfilter/nft_reject_ipv4.c:22:6: symbol 'nft_reject_ipv4_eval' was not declared. Should it be static? yes net/ipv6/netfilter/nf_reject_ipv6.c:16:6: symbol 'nf_send_reset6' was not declared. Should it be static? no; add include net/ipv6/netfilter/nft_reject_ipv6.c:22:6: symbol 'nft_reject_ipv6_eval' was not declared. Should it be static? yes net/netfilter/core.c:33:32: symbol 'nf_ipv6_ops' was not declared. Should it be static? no; add include net/netfilter/xt_DSCP.c:40:57: cast truncates bits from constant value (ffffff03 becomes 3) net/netfilter/xt_DSCP.c:57:59: cast truncates bits from constant value (ffffff03 becomes 3) add __force, 3 is what we want. net/ipv4/netfilter/nf_log_arp.c:77:6: symbol 'nf_log_arp_packet' was not declared. Should it be static? yes net/ipv4/netfilter/nf_reject_ipv4.c:17:6: symbol 'nf_send_reset' was not declared. Should it be static? no; add include Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>