Different namespaces might have different requirements to reuse
TIME-WAIT sockets for new connections. This might be required in
cases where different namespace applications are in place which
require TIME_WAIT socket connections to be reduced independently
of the host.
Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
nf_defrag modules for ipv4 and ipv6 export an empty stub function.
Any module that needs the defragmentation hooks registered simply 'calls'
this empty function to create a phony module dependency -- modprobe will
then load the defrag module too.
This extends netfilter ipv4/ipv6 defragmentation modules to delay the hook
registration until the functionality is requested within a network namespace
instead of module load time for all namespaces.
Hooks are only un-registered on module unload or when a namespace that used
such defrag functionality exits.
We have to use struct net for this as the register hooks can be called
before netns initialization here from the ipv4/ipv6 conntrack module
init path.
There is no unregister functionality support, defrag will always be
active once it was requested inside a net namespace.
The reason is that defrag has impact on nft and iptables rulesets
(without defrag we might see framents).
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
CONFIG_NF_CT_PROTO_UDPLITE is no more a tristate. When set to y,
connection tracking support for UDPlite protocol is built-in into
nf_conntrack.ko.
footprint test:
$ ls -l net/netfilter/nf_conntrack{_proto_udplite,}.ko \
net/ipv4/netfilter/nf_conntrack_ipv4.ko \
net/ipv6/netfilter/nf_conntrack_ipv6.ko
(builtin)|| udplite| ipv4 | ipv6 |nf_conntrack
---------++--------+--------+--------+--------------
none || 432538 | 828755 | 828676 | 6141434
UDPlite || - | 829649 | 829362 | 6498204
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
CONFIG_NF_CT_PROTO_SCTP is no more a tristate. When set to y, connection
tracking support for SCTP protocol is built-in into nf_conntrack.ko.
footprint test:
$ ls -l net/netfilter/nf_conntrack{_proto_sctp,}.ko \
net/ipv4/netfilter/nf_conntrack_ipv4.ko \
net/ipv6/netfilter/nf_conntrack_ipv6.ko
(builtin)|| sctp | ipv4 | ipv6 | nf_conntrack
---------++--------+--------+--------+--------------
none || 498243 | 828755 | 828676 | 6141434
SCTP || - | 829254 | 829175 | 6547872
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
CONFIG_NF_CT_PROTO_DCCP is no more a tristate. When set to y, connection
tracking support for DCCP protocol is built-in into nf_conntrack.ko.
footprint test:
$ ls -l net/netfilter/nf_conntrack{_proto_dccp,}.ko \
net/ipv4/netfilter/nf_conntrack_ipv4.ko \
net/ipv6/netfilter/nf_conntrack_ipv6.ko
(builtin)|| dccp | ipv4 | ipv6 | nf_conntrack
---------++--------+--------+--------+--------------
none || 469140 | 828755 | 828676 | 6141434
DCCP || - | 830566 | 829935 | 6533526
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The next patch will enable listeners of the FIB notification chain to
request a dump of the FIB tables. However, since RTNL isn't taken during
the dump, it's possible for the FIB tables to change mid-dump, which
will result in inconsistency between the listener's table and the
kernel's.
Allow listeners to know about changes that occurred mid-dump, by adding
a change sequence counter to each net namespace. The counter is
incremented just before a notification is sent in the FIB chain.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net_generic() function is both a) inline and b) used ~600 times.
It has the following code inside
...
ptr = ng->ptr[id - 1];
...
"id" is never compile time constant so compiler is forced to subtract 1.
And those decrements or LEA [r32 - 1] instructions add up.
We also start id'ing from 1 to catch bugs where pernet sybsystem id
is not initialized and 0. This is quite pointless idea (nothing will
work or immediate interference with first registered subsystem) in
general but it hints what needs to be done for code size reduction.
Namely, overlaying allocation of pointer array and fixed part of
structure in the beginning and using usual base-0 addressing.
Ids are just cookies, their exact values do not matter, so lets start
with 3 on x86_64.
Code size savings (oh boy): -4.2 KB
As usual, ignore the initial compiler stupidity part of the table.
add/remove: 0/0 grow/shrink: 12/670 up/down: 89/-4297 (-4208)
function old new delta
tipc_nametbl_insert_publ 1250 1270 +20
nlmclnt_lookup_host 686 703 +17
nfsd4_encode_fattr 5930 5941 +11
nfs_get_client 1050 1061 +11
register_pernet_operations 333 342 +9
tcf_mirred_init 843 849 +6
tcf_bpf_init 1143 1149 +6
gss_setup_upcall 990 994 +4
idmap_name_to_id 432 434 +2
ops_init 274 275 +1
nfsd_inject_forget_client 259 260 +1
nfs4_alloc_client 612 613 +1
tunnel_key_walker 164 163 -1
...
tipc_bcbase_select_primary 392 360 -32
mac80211_hwsim_new_radio 2808 2767 -41
ipip6_tunnel_ioctl 2228 2186 -42
tipc_bcast_rcv 715 672 -43
tipc_link_build_proto_msg 1140 1089 -51
nfsd4_lock 3851 3796 -55
tipc_mon_rcv 1012 956 -56
Total: Before=156643951, After=156639743, chg -0.00%
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is precursor to fixing "[id - 1]" bloat inside net_generic().
Name "s" is chosen to complement name "u" often used for dummy unions.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make struct pernet_operations::id unsigned.
There are 2 reasons to do so:
1)
This field is really an index into an zero based array and
thus is unsigned entity. Using negative value is out-of-bound
access by definition.
2)
On x86_64 unsigned 32-bit data which are mixed with pointers
via array indexing or offsets added or subtracted to pointers
are preffered to signed 32-bit data.
"int" being used as an array index needs to be sign-extended
to 64-bit before being used.
void f(long *p, int i)
{
g(p[i]);
}
roughly translates to
movsx rsi, esi
mov rdi, [rsi+...]
call g
MOVSX is 3 byte instruction which isn't necessary if the variable is
unsigned because x86_64 is zero extending by default.
Now, there is net_generic() function which, you guessed it right, uses
"int" as an array index:
static inline void *net_generic(const struct net *net, int id)
{
...
ptr = ng->ptr[id - 1];
...
}
And this function is used a lot, so those sign extensions add up.
Patch snipes ~1730 bytes on allyesconfig kernel (without all junk
messing with code generation):
add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)
Unfortunately some functions actually grow bigger.
This is a semmingly random artefact of code generation with register
allocator being used differently. gcc decides that some variable
needs to live in new r8+ registers and every access now requires REX
prefix. Or it is shifted into r12, so [r12+0] addressing mode has to be
used which is longer than [r8]
However, overall balance is in negative direction:
add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)
function old new delta
nfsd4_lock 3886 3959 +73
tipc_link_build_proto_msg 1096 1140 +44
mac80211_hwsim_new_radio 2776 2808 +32
tipc_mon_rcv 1032 1058 +26
svcauth_gss_legacy_init 1413 1429 +16
tipc_bcbase_select_primary 379 392 +13
nfsd4_exchange_id 1247 1260 +13
nfsd4_setclientid_confirm 782 793 +11
...
put_client_renew_locked 494 480 -14
ip_set_sockfn_get 730 716 -14
geneve_sock_add 829 813 -16
nfsd4_sequence_done 721 703 -18
nlmclnt_lookup_host 708 686 -22
nfsd4_lockt 1085 1063 -22
nfs_get_client 1077 1050 -27
tcf_bpf_init 1106 1076 -30
nfsd4_encode_fattr 5997 5930 -67
Total: Before=154856051, After=154854321, chg -0.00%
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
Netfilter updates for net-next
The following patchset contains a second batch of Netfilter updates for
your net-next tree. This includes a rework of the core hook
infrastructure that improves Netfilter performance by ~15% according to
synthetic benchmarks. Then, a large batch with ipset updates, including
a new hash:ipmac set type, via Jozsef Kadlecsik. This also includes a
couple of assorted updates.
Regarding the core hook infrastructure rework to improve performance,
using this simple drop-all packets ruleset from ingress:
nft add table netdev x
nft add chain netdev x y { type filter hook ingress device eth0 priority 0\; }
nft add rule netdev x y drop
And generating traffic through Jesper Brouer's
samples/pktgen/pktgen_bench_xmit_mode_netif_receive.sh script using -i
option. perf report shows nf_tables calls in its top 10:
17.30% kpktgend_0 [nf_tables] [k] nft_do_chain
15.75% kpktgend_0 [kernel.vmlinux] [k] __netif_receive_skb_core
10.39% kpktgend_0 [nf_tables_netdev] [k] nft_do_chain_netdev
I'm measuring here an improvement of ~15% in performance with this
patchset, so we got +2.5Mpps more. I have used my old laptop Intel(R)
Core(TM) i5-3320M CPU @ 2.60GHz 4-cores.
This rework contains more specifically, in strict order, these patches:
1) Remove compile-time debugging from core.
2) Remove obsolete comments that predate the rcu era. These days it is
well known that a Netfilter hook always runs under rcu_read_lock().
3) Remove threshold handling, this is only used by br_netfilter too.
We already have specific code to handle this from br_netfilter,
so remove this code from the core path.
4) Deprecate NF_STOP, as this is only used by br_netfilter.
5) Place nf_state_hook pointer into xt_action_param structure, so
this structure fits into one single cacheline according to pahole.
This also implicit affects nftables since it also relies on the
xt_action_param structure.
6) Move state->hook_entries into nf_queue entry. The hook_entries
pointer is only required by nf_queue(), so we can store this in the
queue entry instead.
7) use switch() statement to handle verdict cases.
8) Remove hook_entries field from nf_hook_state structure, this is only
required by nf_queue, so store it in nf_queue_entry structure.
9) Merge nf_iterate() into nf_hook_slow() that results in a much more
simple and readable function.
10) Handle NF_REPEAT away from the core, so far the only client is
nf_conntrack_in() and we can restart the packet processing using a
simple goto to jump back there when the TCP requires it.
This update required a second pass to fix fallout, fix from
Arnd Bergmann.
11) Set random seed from nft_hash when no seed is specified from
userspace.
12) Simplify nf_tables expression registration, in a much smarter way
to save lots of boiler plate code, by Liping Zhang.
13) Simplify layer 4 protocol conntrack tracker registration, from
Davide Caratti.
14) Missing CONFIG_NF_SOCKET_IPV4 dependency for udp4_lib_lookup, due
to recent generalization of the socket infrastructure, from Arnd
Bergmann.
15) Then, the ipset batch from Jozsef, he describes it as it follows:
* Cleanup: Remove extra whitespaces in ip_set.h
* Cleanup: Mark some of the helpers arguments as const in ip_set.h
* Cleanup: Group counter helper functions together in ip_set.h
* struct ip_set_skbinfo is introduced instead of open coded fields
in skbinfo get/init helper funcions.
* Use kmalloc() in comment extension helper instead of kzalloc()
because it is unnecessary to zero out the area just before
explicit initialization.
* Cleanup: Split extensions into separate files.
* Cleanup: Separate memsize calculation code into dedicated function.
* Cleanup: group ip_set_put_extensions() and ip_set_get_extensions()
together.
* Add element count to hash headers by Eric B Munson.
* Add element count to all set types header for uniform output
across all set types.
* Count non-static extension memory into memsize calculation for
userspace.
* Cleanup: Remove redundant mtype_expire() arguments, because
they can be get from other parameters.
* Cleanup: Simplify mtype_expire() for hash types by removing
one level of intendation.
* Make NLEN compile time constant for hash types.
* Make sure element data size is a multiple of u32 for the hash set
types.
* Optimize hash creation routine, exit as early as possible.
* Make struct htype per ipset family so nets array becomes fixed size
and thus simplifies the struct htype allocation.
* Collapse same condition body into a single one.
* Fix reported memory size for hash:* types, base hash bucket structure
was not taken into account.
* hash:ipmac type support added to ipset by Tomasz Chilinski.
* Use setup_timer() and mod_timer() instead of init_timer()
by Muhammad Falak R Wani, individually for the set type families.
16) Remove useless connlabel field in struct netns_ct, patch from
Florian Westphal.
17) xt_find_table_lock() doesn't return ERR_PTR() anymore, so simplify
{ip,ip6,arp}tables code that uses this.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
since 23014011ba ('netfilter: conntrack: support a fixed size of 128 distinct labels')
this isn't needed anymore.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This patch adds the necessary hooks and structures to provide support
for SR-IPv6 control plane, essentially the Generic Netlink commands
that will be used for userspace control over the Segment Routing
kernel structures.
The genetlink commands provide control over two different structures:
tunnel source and HMAC data. The tunnel source is the source address
that will be used by default when encapsulating packets into an
outer IPv6 header + SRH. If the tunnel source is set to :: then an
address of the outgoing interface will be selected as the source.
The HMAC commands currently just return ENOTSUPP and will be implemented
in a future patch.
Signed-off-by: David Lebrun <david.lebrun@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
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 c73c248490 ("netfilter: nf_tables_netdev: remove redundant
ip_hdr assignment") from the net tree and commit ddc8b6027a
("netfilter: introduce nft_set_pktinfo_{ipv4, ipv6}_validate()").
2) Between e8bffe0cf9 ("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>
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>
Steffen Klassert says:
====================
ipsec-next 2016-09-08
1) Constify the xfrm_replay structures. From Julia Lawall
2) Protect xfrm state hash tables with rcu, lookups
can be done now without acquiring xfrm_state_lock.
From Florian Westphal.
3) Protect xfrm policy hash tables with rcu, lookups
can be done now without acquiring xfrm_policy_lock.
From Florian Westphal.
4) We don't need to have a garbage collector list per
namespace anymore, so use a global one instead.
From Florian Westphal.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
After commit 5b8ef3415a
("xfrm: Remove ancient sleeping when the SA is in acquire state")
gc does not need any per-netns data anymore.
As far as gc is concerned all state structs are the same, so we
can use a global work struct for it.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
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>
After earlier patches conversions all spots acquire the writer lock and
we can now convert this to a normal spinlock.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
push the lock down, after earlier patches we can rely on rcu to
make sure state struct won't go away.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
After commit 0ddcf43d5d ("ipv4: FIB Local/MAIN table collapse")
fib_local is set but not used. Remove it.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contains Netfilter fixes for your net tree,
they are:
1) Fix incorrect timestamp in nfnetlink_queue introduced when addressing
y2038 safe timestamp, from Florian Westphal.
2) Get rid of leftover conntrack definition from the previous merge
window, oneliner from Florian.
3) Make nf_queue handler pernet to resolve race on dereferencing the
hook state structure with netns removal, from Eric Biederman.
4) Ensure clean exit on unregistered helper ports, from Taehee Yoo.
5) Restore FLOWI_FLAG_KNOWN_NH in nf_dup_ipv6. This got lost while
generalizing xt_TEE to add packet duplication support in nf_tables,
from Paolo Abeni.
6) Insufficient netlink NFTA_SET_TABLE attribute check in
nf_tables_getset(), from Phil Turnbull.
7) Reject helper registration on duplicated ports via modparams.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Florian Weber reported:
> Under full load (unshare() in loop -> OOM conditions) we can
> get kernel panic:
>
> BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
> IP: [<ffffffff81476c85>] nfqnl_nf_hook_drop+0x35/0x70
> [..]
> task: ffff88012dfa3840 ti: ffff88012dffc000 task.ti: ffff88012dffc000
> RIP: 0010:[<ffffffff81476c85>] [<ffffffff81476c85>] nfqnl_nf_hook_drop+0x35/0x70
> RSP: 0000:ffff88012dfffd80 EFLAGS: 00010206
> RAX: 0000000000000008 RBX: ffffffff81add0c0 RCX: ffff88013fd80000
> [..]
> Call Trace:
> [<ffffffff81474d98>] nf_queue_nf_hook_drop+0x18/0x20
> [<ffffffff814738eb>] nf_unregister_net_hook+0xdb/0x150
> [<ffffffff8147398f>] netfilter_net_exit+0x2f/0x60
> [<ffffffff8141b088>] ops_exit_list.isra.4+0x38/0x60
> [<ffffffff8141b652>] setup_net+0xc2/0x120
> [<ffffffff8141bd09>] copy_net_ns+0x79/0x120
> [<ffffffff8106965b>] create_new_namespaces+0x11b/0x1e0
> [<ffffffff810698a7>] unshare_nsproxy_namespaces+0x57/0xa0
> [<ffffffff8104baa2>] SyS_unshare+0x1b2/0x340
> [<ffffffff81608276>] entry_SYSCALL_64_fastpath+0x1e/0xa8
> Code: 65 00 48 89 e5 41 56 41 55 41 54 53 83 e8 01 48 8b 97 70 12 00 00 48 98 49 89 f4 4c 8b 74 c2 18 4d 8d 6e 08 49 81 c6 88 00 00 00 <49> 8b 5d 00 48 85 db 74 1a 48 89 df 4c 89 e2 48 c7 c6 90 68 47
>
The simple fix for this requires a new pernet variable for struct
nf_queue that indicates when it is safe to use the dynamically
allocated nf_queue state.
As we need a variable anyway make nf_register_queue_handler and
nf_unregister_queue_handler pernet. This allows the existing logic of
when it is safe to use the state from the nfnetlink_queue module to be
reused with no changes except for making it per net.
The syncrhonize_rcu from nf_unregister_queue_handler is moved to a new
function nfnl_queue_net_exit_batch so that the worst case of having a
syncrhonize_rcu in the pernet exit path is not experienced in batch
mode.
Reported-by: Florian Westphal <fw@strlen.de>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
In netdevice.h we removed the structure in net-next that is being
changes in 'net'. In macsec.c and rtnetlink.c we have overlaps
between fixes in 'net' and the u64 attribute changes in 'net-next'.
The mlx5 conflicts have to do with vxlan support dependencies.
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
We already include netns address in the hash, so we only need to use
net_eq in find_appropriate_src and can then put all entries into
same table.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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 expectation table.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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>
Steffen Klassert says:
====================
pull request (net): ipsec 2016-05-04
1) The flowcache can hit an OOM condition if too
many entries are in the gc_list. Fix this by
counting the entries in the gc_list and refuse
new allocations if the value is too high.
2) The inner headers are invalid after a xfrm transformation,
so reset the skb encapsulation field to ensure nobody tries
access the inner headers. Otherwise tunnel devices stacked
on top of xfrm may build the outer headers based on wrong
informations.
3) Add pmtu handling to vti, we need it to report
pmtu informations for local generated packets.
Please pull or let me know if there are problems.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
Multipath route lookups should consider knowledge about next hops and not
select a hop that is known to be failed.
Example:
[h2] [h3] 15.0.0.5
| |
3| 3|
[SP1] [SP2]--+
1 2 1 2
| | /-------------+ |
| \ / |
| X |
| / \ |
| / \---------------\ |
1 2 1 2
12.0.0.2 [TOR1] 3-----------------3 [TOR2] 12.0.0.3
4 4
\ /
\ /
\ /
-------| |-----/
1 2
[TOR3]
3|
|
[h1] 12.0.0.1
host h1 with IP 12.0.0.1 has 2 paths to host h3 at 15.0.0.5:
root@h1:~# ip ro ls
...
12.0.0.0/24 dev swp1 proto kernel scope link src 12.0.0.1
15.0.0.0/16
nexthop via 12.0.0.2 dev swp1 weight 1
nexthop via 12.0.0.3 dev swp1 weight 1
...
If the link between tor3 and tor1 is down and the link between tor1
and tor2 then tor1 is effectively cut-off from h1. Yet the route lookups
in h1 are alternating between the 2 routes: ping 15.0.0.5 gets one and
ssh 15.0.0.5 gets the other. Connections that attempt to use the
12.0.0.2 nexthop fail since that neighbor is not reachable:
root@h1:~# ip neigh show
...
12.0.0.3 dev swp1 lladdr 00:02:00:00:00:1b REACHABLE
12.0.0.2 dev swp1 FAILED
...
The failed path can be avoided by considering known neighbor information
when selecting next hops. If the neighbor lookup fails we have no
knowledge about the nexthop, so give it a shot. If there is an entry
then only select the nexthop if the state is sane. This is similar to
what fib_detect_death does.
To maintain backward compatibility use of the neighbor information is
based on a new sysctl, fib_multipath_use_neigh.
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Reviewed-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
We can hit an OOM condition if we are under presure because
we can not free the entries in gc_list fast enough. So add
a counter for the not yet freed entries in the gc_list and
refuse new allocations if the value is too high.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
One of our customers observed issues with FIB6 garbage collectors
running in different network namespaces blocking each other, resulting
in soft lockups (fib6_run_gc() initiated from timer runs always in
forced mode).
Now that FIB6 walkers are separated per namespace, there is no more need
for instances of fib6_run_gc() in different namespaces blocking each
other. There is still a call to icmp6_dst_gc() which operates on shared
data but this function is protected by its own shared lock.
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Reviewed-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The IPv6 FIB data structures are separated per network namespace but
there is still only one global walkers list and one global walker list
lock. This means changes in one namespace unnecessarily interfere with
walkers in other namespaces.
Replace the global list with per-netns lists (and give each its own
lock).
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Reviewed-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This was initially introduced in df2cf4a78e ("IGMP: Inhibit
reports for local multicast groups") by defining the sysctl in the
ipv4_net_table array, however it was never implemented to be
namespace aware. Fix this by changing the code accordingly.
Signed-off-by: David S. Miller <davem@davemloft.net>
Haishuang Yan