We may lost race if we flush the rule-set (which happens asynchronously
via call_rcu) and we try to remove the table (that userspace assumes
to be empty).
Fix this by recovering synchronous rule and chain deletion. This was
introduced time ago before we had no batch support, and synchronous
rule deletion performance was not good. Now that we have the batch
support, we can just postpone the purge of old rule in a second step
in the commit phase. All object deletions are synchronous after this
patch.
As a side effect, we save memory as we don't need rcu_head per rule
anymore.
Cc: Patrick McHardy <kaber@trash.net>
Reported-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The log and queue expressions both store the family during ->init() and
use it to deliver packets. This is wrong when used in NFPROTO_INET since
they should both deliver to the actual AF of the packet, not the dummy
NFPROTO_INET.
Use the family from the hook ops to fix this.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Add a reject module for NFPROTO_INET. It does nothing but dispatch
to the AF-specific modules based on the hook family.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Currently the nft_reject module depends on symbols from ipv6. This is
wrong since no generic module should force IPv6 support to be loaded.
Split up the module into AF-specific and a generic part.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
For the reject module, we need to add AF-specific implementations to
get rid of incorrect module dependencies. Try to load an AF-specific
module first and fall back to generic modules.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The key was missing in the list of valid keys, add it.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Commit c9c8e48597 (netfilter: nf_tables: dump sets in all existing families)
changed nft_ctx_init_from_setattr() to only look up the address family if it
is not NFPROTO_UNSPEC. However if it is NFPROTO_UNSPEC and a table attribute
is given, nftables_afinfo_lookup() will dereference the NULL afi pointer.
Fix by checking for non-NULL afi and also move a check added by that commit
to the proper position.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The map that is used to allocate anonymous sets is indeed
BITS_PER_BYTE * PAGE_SIZE long.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
With this patch, the conntrack refcount is initially set to zero and
it is bumped once it is added to any of the list, so we fulfill
Eric's golden rule which is that all released objects always have a
refcount that equals zero.
Andrey Vagin reports that nf_conntrack_free can't be called for a
conntrack with non-zero ref-counter, because it can race with
nf_conntrack_find_get().
A conntrack slab is created with SLAB_DESTROY_BY_RCU. Non-zero
ref-counter says that this conntrack is used. So when we release
a conntrack with non-zero counter, we break this assumption.
CPU1 CPU2
____nf_conntrack_find()
nf_ct_put()
destroy_conntrack()
...
init_conntrack
__nf_conntrack_alloc (set use = 1)
atomic_inc_not_zero(&ct->use) (use = 2)
if (!l4proto->new(ct, skb, dataoff, timeouts))
nf_conntrack_free(ct); (use = 2 !!!)
...
__nf_conntrack_alloc (set use = 1)
if (!nf_ct_key_equal(h, tuple, zone))
nf_ct_put(ct); (use = 0)
destroy_conntrack()
/* continue to work with CT */
After applying the path "[PATCH] netfilter: nf_conntrack: fix RCU
race in nf_conntrack_find_get" another bug was triggered in
destroy_conntrack():
<4>[67096.759334] ------------[ cut here ]------------
<2>[67096.759353] kernel BUG at net/netfilter/nf_conntrack_core.c:211!
...
<4>[67096.759837] Pid: 498649, comm: atdd veid: 666 Tainted: G C --------------- 2.6.32-042stab084.18 #1 042stab084_18 /DQ45CB
<4>[67096.759932] RIP: 0010:[<ffffffffa03d99ac>] [<ffffffffa03d99ac>] destroy_conntrack+0x15c/0x190 [nf_conntrack]
<4>[67096.760255] Call Trace:
<4>[67096.760255] [<ffffffff814844a7>] nf_conntrack_destroy+0x17/0x30
<4>[67096.760255] [<ffffffffa03d9bb5>] nf_conntrack_find_get+0x85/0x130 [nf_conntrack]
<4>[67096.760255] [<ffffffffa03d9fb2>] nf_conntrack_in+0x352/0xb60 [nf_conntrack]
<4>[67096.760255] [<ffffffffa048c771>] ipv4_conntrack_local+0x51/0x60 [nf_conntrack_ipv4]
<4>[67096.760255] [<ffffffff81484419>] nf_iterate+0x69/0xb0
<4>[67096.760255] [<ffffffff814b5b00>] ? dst_output+0x0/0x20
<4>[67096.760255] [<ffffffff814845d4>] nf_hook_slow+0x74/0x110
<4>[67096.760255] [<ffffffff814b5b00>] ? dst_output+0x0/0x20
<4>[67096.760255] [<ffffffff814b66d5>] raw_sendmsg+0x775/0x910
<4>[67096.760255] [<ffffffff8104c5a8>] ? flush_tlb_others_ipi+0x128/0x130
<4>[67096.760255] [<ffffffff8100bc4e>] ? apic_timer_interrupt+0xe/0x20
<4>[67096.760255] [<ffffffff8100bc4e>] ? apic_timer_interrupt+0xe/0x20
<4>[67096.760255] [<ffffffff814c136a>] inet_sendmsg+0x4a/0xb0
<4>[67096.760255] [<ffffffff81444e93>] ? sock_sendmsg+0x13/0x140
<4>[67096.760255] [<ffffffff81444f97>] sock_sendmsg+0x117/0x140
<4>[67096.760255] [<ffffffff8102e299>] ? native_smp_send_reschedule+0x49/0x60
<4>[67096.760255] [<ffffffff81519beb>] ? _spin_unlock_bh+0x1b/0x20
<4>[67096.760255] [<ffffffff8109d930>] ? autoremove_wake_function+0x0/0x40
<4>[67096.760255] [<ffffffff814960f0>] ? do_ip_setsockopt+0x90/0xd80
<4>[67096.760255] [<ffffffff8100bc4e>] ? apic_timer_interrupt+0xe/0x20
<4>[67096.760255] [<ffffffff8100bc4e>] ? apic_timer_interrupt+0xe/0x20
<4>[67096.760255] [<ffffffff814457c9>] sys_sendto+0x139/0x190
<4>[67096.760255] [<ffffffff810efa77>] ? audit_syscall_entry+0x1d7/0x200
<4>[67096.760255] [<ffffffff810ef7c5>] ? __audit_syscall_exit+0x265/0x290
<4>[67096.760255] [<ffffffff81474daf>] compat_sys_socketcall+0x13f/0x210
<4>[67096.760255] [<ffffffff8104dea3>] ia32_sysret+0x0/0x5
I have reused the original title for the RFC patch that Andrey posted and
most of the original patch description.
Cc: Eric Dumazet <edumazet@google.com>
Cc: Andrew Vagin <avagin@parallels.com>
Cc: Florian Westphal <fw@strlen.de>
Reported-by: Andrew Vagin <avagin@parallels.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Andrew Vagin <avagin@parallels.com>
Lets look at destroy_conntrack:
hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode);
...
nf_conntrack_free(ct)
kmem_cache_free(net->ct.nf_conntrack_cachep, ct);
net->ct.nf_conntrack_cachep is created with SLAB_DESTROY_BY_RCU.
The hash is protected by rcu, so readers look up conntracks without
locks.
A conntrack is removed from the hash, but in this moment a few readers
still can use the conntrack. Then this conntrack is released and another
thread creates conntrack with the same address and the equal tuple.
After this a reader starts to validate the conntrack:
* It's not dying, because a new conntrack was created
* nf_ct_tuple_equal() returns true.
But this conntrack is not initialized yet, so it can not be used by two
threads concurrently. In this case BUG_ON may be triggered from
nf_nat_setup_info().
Florian Westphal suggested to check the confirm bit too. I think it's
right.
task 1 task 2 task 3
nf_conntrack_find_get
____nf_conntrack_find
destroy_conntrack
hlist_nulls_del_rcu
nf_conntrack_free
kmem_cache_free
__nf_conntrack_alloc
kmem_cache_alloc
memset(&ct->tuplehash[IP_CT_DIR_MAX],
if (nf_ct_is_dying(ct))
if (!nf_ct_tuple_equal()
I'm not sure, that I have ever seen this race condition in a real life.
Currently we are investigating a bug, which is reproduced on a few nodes.
In our case one conntrack is initialized from a few tasks concurrently,
we don't have any other explanation for this.
<2>[46267.083061] kernel BUG at net/ipv4/netfilter/nf_nat_core.c:322!
...
<4>[46267.083951] RIP: 0010:[<ffffffffa01e00a4>] [<ffffffffa01e00a4>] nf_nat_setup_info+0x564/0x590 [nf_nat]
...
<4>[46267.085549] Call Trace:
<4>[46267.085622] [<ffffffffa023421b>] alloc_null_binding+0x5b/0xa0 [iptable_nat]
<4>[46267.085697] [<ffffffffa02342bc>] nf_nat_rule_find+0x5c/0x80 [iptable_nat]
<4>[46267.085770] [<ffffffffa0234521>] nf_nat_fn+0x111/0x260 [iptable_nat]
<4>[46267.085843] [<ffffffffa0234798>] nf_nat_out+0x48/0xd0 [iptable_nat]
<4>[46267.085919] [<ffffffff814841b9>] nf_iterate+0x69/0xb0
<4>[46267.085991] [<ffffffff81494e70>] ? ip_finish_output+0x0/0x2f0
<4>[46267.086063] [<ffffffff81484374>] nf_hook_slow+0x74/0x110
<4>[46267.086133] [<ffffffff81494e70>] ? ip_finish_output+0x0/0x2f0
<4>[46267.086207] [<ffffffff814b5890>] ? dst_output+0x0/0x20
<4>[46267.086277] [<ffffffff81495204>] ip_output+0xa4/0xc0
<4>[46267.086346] [<ffffffff814b65a4>] raw_sendmsg+0x8b4/0x910
<4>[46267.086419] [<ffffffff814c10fa>] inet_sendmsg+0x4a/0xb0
<4>[46267.086491] [<ffffffff814459aa>] ? sock_update_classid+0x3a/0x50
<4>[46267.086562] [<ffffffff81444d67>] sock_sendmsg+0x117/0x140
<4>[46267.086638] [<ffffffff8151997b>] ? _spin_unlock_bh+0x1b/0x20
<4>[46267.086712] [<ffffffff8109d370>] ? autoremove_wake_function+0x0/0x40
<4>[46267.086785] [<ffffffff81495e80>] ? do_ip_setsockopt+0x90/0xd80
<4>[46267.086858] [<ffffffff8100be0e>] ? call_function_interrupt+0xe/0x20
<4>[46267.086936] [<ffffffff8118cb10>] ? ub_slab_ptr+0x20/0x90
<4>[46267.087006] [<ffffffff8118cb10>] ? ub_slab_ptr+0x20/0x90
<4>[46267.087081] [<ffffffff8118f2e8>] ? kmem_cache_alloc+0xd8/0x1e0
<4>[46267.087151] [<ffffffff81445599>] sys_sendto+0x139/0x190
<4>[46267.087229] [<ffffffff81448c0d>] ? sock_setsockopt+0x16d/0x6f0
<4>[46267.087303] [<ffffffff810efa47>] ? audit_syscall_entry+0x1d7/0x200
<4>[46267.087378] [<ffffffff810ef795>] ? __audit_syscall_exit+0x265/0x290
<4>[46267.087454] [<ffffffff81474885>] ? compat_sys_setsockopt+0x75/0x210
<4>[46267.087531] [<ffffffff81474b5f>] compat_sys_socketcall+0x13f/0x210
<4>[46267.087607] [<ffffffff8104dea3>] ia32_sysret+0x0/0x5
<4>[46267.087676] Code: 91 20 e2 01 75 29 48 89 de 4c 89 f7 e8 56 fa ff ff 85 c0 0f 84 68 fc ff ff 0f b6 4d c6 41 8b 45 00 e9 4d fb ff ff e8 7c 19 e9 e0 <0f> 0b eb fe f6 05 17 91 20 e2 80 74 ce 80 3d 5f 2e 00 00 00 74
<1>[46267.088023] RIP [<ffffffffa01e00a4>] nf_nat_setup_info+0x564/0x590
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The following commands trigger an oops:
# nft -i
nft> add table filter
nft> add chain filter input { type filter hook input priority 0; }
nft> add chain filter test
nft> add rule filter input jump test
nft> delete chain filter test
We need to check the chain use counter before allowing destruction since
we might have references from sets or jump rules.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=69341
Reported-by: Matthew Ife <deleriux1@gmail.com>
Tested-by: Matthew Ife <deleriux1@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We want to make sure that the information that we get from the kernel can
be reinjected without troubles. The kernel shouldn't return an attribute
that is not required, or even prohibited.
Dumping unconditionally NFTA_CT_DIRECTION could lead an application in
userspace to interpret that the attribute was originally set, while it
was not.
Signed-off-by: Arturo Borrero Gonzalez <arturo.borrero.glez@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
If a fwmark is passed to ip_vs_conn_new(), it is passed in
vaddr, not daddr. Therefore we should set AF to AF_UNSPEC in
vaddr assignment (like we do in ip_vs_ct_in_get()), otherwise we
may copy only first 4 bytes of an IPv6 address into cp->daddr.
Signed-off-by: Bogdano Arendartchuk <barendartchuk@suse.com>
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
From 038a821667f62c496f2bbae27081b1b612122a97 Mon Sep 17 00:00:00 2001
From: Martin Schwenke <martin@meltin.net>
Date: Tue, 28 Jan 2014 15:16:49 +1100
Subject: [PATCH] net: Document promote_secondaries
This option was added a long time ago...
commit 8f937c6099
Author: Harald Welte <laforge@gnumonks.org>
Date: Sun May 29 20:23:46 2005 -0700
[IPV4]: Primary and secondary addresses
Signed-off-by: Martin Schwenke <martin@meltin.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
When dealing with icmp messages, the skb->data points the
ip header that triggered the sending of the icmp message.
In gre_cisco_err(), the parse_gre_header() is called, and the
iptunnel_pull_header() is called to pull the skb at the end of
the parse_gre_header(), so the skb->data doesn't point the
inner ip header.
Unfortunately, the ipgre_err still needs those ip addresses in
inner ip header to look up tunnel by ip_tunnel_lookup().
So just use icmp_hdr() to get inner ip header instead of skb->data.
Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Indentation mismatch spotted with Coverity.
Introduced in 4e3b35b044 ("i40e: add DCB and DCBNL support")
Signed-off-by: Dave Jones <davej@fedoraproject.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch removes grant transfer releasing code from netfront, and uses
gnttab_end_foreign_access to end grant access since
gnttab_end_foreign_access_ref may fail when the grant entry is
currently used for reading or writing.
* clean up grant transfer code kept from old netfront(2.6.18) which grants
pages for access/map and transfer. But grant transfer is deprecated in current
netfront, so remove corresponding release code for transfer.
* fix resource leak, release grant access (through gnttab_end_foreign_access)
and skb for tx/rx path, use get_page to ensure page is released when grant
access is completed successfully.
Xen-blkfront/xen-tpmfront/xen-pcifront also have similar issue, but patches
for them will be created separately.
V6: Correct subject line and commit message.
V5: Remove unecessary change in xennet_end_access.
V4: Revert put_page in gnttab_end_foreign_access, and keep netfront change in
single patch.
V3: Changes as suggestion from David Vrabel, ensure pages are not freed untill
grant acess is ended.
V2: Improve patch comments.
Signed-off-by: Annie Li <annie.li@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This will allow us to use bigger receive buffer, and prevent allocation failure
due to fragmented memory.
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I see a memory leak when using a transparent HTTP proxy using TPROXY
together with TCP early demux and Kernel v3.8.13.15 (Ubuntu stable):
unreferenced object 0xffff88008cba4a40 (size 1696):
comm "softirq", pid 0, jiffies 4294944115 (age 8907.520s)
hex dump (first 32 bytes):
0a e0 20 6a 40 04 1b 37 92 be 32 e2 e8 b4 00 00 .. j@..7..2.....
02 00 07 01 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff810b710a>] kmem_cache_alloc+0xad/0xb9
[<ffffffff81270185>] sk_prot_alloc+0x29/0xc5
[<ffffffff812702cf>] sk_clone_lock+0x14/0x283
[<ffffffff812aaf3a>] inet_csk_clone_lock+0xf/0x7b
[<ffffffff8129a893>] netlink_broadcast+0x14/0x16
[<ffffffff812c1573>] tcp_create_openreq_child+0x1b/0x4c3
[<ffffffff812c033e>] tcp_v4_syn_recv_sock+0x38/0x25d
[<ffffffff812c13e4>] tcp_check_req+0x25c/0x3d0
[<ffffffff812bf87a>] tcp_v4_do_rcv+0x287/0x40e
[<ffffffff812a08a7>] ip_route_input_noref+0x843/0xa55
[<ffffffff812bfeca>] tcp_v4_rcv+0x4c9/0x725
[<ffffffff812a26f4>] ip_local_deliver_finish+0xe9/0x154
[<ffffffff8127a927>] __netif_receive_skb+0x4b2/0x514
[<ffffffff8127aa77>] process_backlog+0xee/0x1c5
[<ffffffff8127c949>] net_rx_action+0xa7/0x200
[<ffffffff81209d86>] add_interrupt_randomness+0x39/0x157
But there are many more, resulting in the machine going OOM after some
days.
From looking at the TPROXY code, and with help from Florian, I see
that the memory leak is introduced in tcp_v4_early_demux():
void tcp_v4_early_demux(struct sk_buff *skb)
{
/* ... */
iph = ip_hdr(skb);
th = tcp_hdr(skb);
if (th->doff < sizeof(struct tcphdr) / 4)
return;
sk = __inet_lookup_established(dev_net(skb->dev), &tcp_hashinfo,
iph->saddr, th->source,
iph->daddr, ntohs(th->dest),
skb->skb_iif);
if (sk) {
skb->sk = sk;
where the socket is assigned unconditionally to skb->sk, also bumping
the refcnt on it. This is problematic, because in our case the skb
has already a socket assigned in the TPROXY target. This then results
in the leak I see.
The very same issue seems to be with IPv6, but haven't tested.
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Holger Eitzenberger <holger@eitzenberger.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Veaceslav Falico says:
====================
bonding: fix locking in bond_ab_arp_prob
After the latest patches, on every call of bond_ab_arp_probe() without an
active slave I see the following warning:
[ 7.912314] RTNL: assertion failed at net/core/dev.c (4494)
...
[ 7.922495] [<ffffffff817acc6f>] dump_stack+0x51/0x72
[ 7.923714] [<ffffffff8168795e>] netdev_master_upper_dev_get+0x6e/0x70
[ 7.924940] [<ffffffff816a2a66>] rtnl_link_fill+0x116/0x260
[ 7.926143] [<ffffffff817acc6f>] ? dump_stack+0x51/0x72
[ 7.927333] [<ffffffff816a350c>] rtnl_fill_ifinfo+0x95c/0xb90
[ 7.928529] [<ffffffff8167af2b>] ? __kmalloc_reserve+0x3b/0xa0
[ 7.929681] [<ffffffff8167bfcf>] ? __alloc_skb+0x9f/0x1e0
[ 7.930827] [<ffffffff816a3b64>] rtmsg_ifinfo+0x84/0x100
[ 7.931960] [<ffffffffa00bca07>] bond_ab_arp_probe+0x1a7/0x370 [bonding]
[ 7.933133] [<ffffffffa00bcd78>] bond_activebackup_arp_mon+0x1a8/0x2f0 [bonding]
...
It happens because in bond_ab_arp_probe() we change the flags of a slave
without holding the RTNL lock.
To fix this - remove the useless curr_active_lock, RCUify it and lock RTNL
while changing the slave's flags. Also, remove bond_ab_arp_probe() from
under any locks in bond_ab_arp_mon().
====================
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently we're calling it from under RCU context, however we're using some
functions that require rtnl to be held.
Fix this by restructuring the locking - don't call it under any locks,
aquire rcu_read_lock() if we're sending _only_ (i.e. we have the active
slave present), and use rtnl locking otherwise - if we need to modify
(in)active flags of a slave.
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently bond_ab_arp_probe() is always called under rcu_read_lock(),
however to work with curr_active_slave we're still holding the
curr_slave_lock.
To remove that curr_slave_lock - rcu_dereference the bond's
curr_active_slave and use it further - so that we're sure the slave won't
go away, and we don't care if it will change in the meanwhile.
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso
Patrick McHardy
Alexey Dobriyan
Andrey Vagin
Arturo Borrero
Michal Kubecek
Martin Schwenke
Duan Jiong
Dave Jones
Annie Li
Stephen Rothwell
Haiyang Zhang
Stanislaw Gruszka
Holger Eitzenberger
David S. Miller
Veaceslav Falico