linux-stable.git/net/ipv4/netfilter, branch linux-5.0.y Linux kernel stable tree netfilter: nat: fix spurious connection timeouts 2019-02-11T16:43:17+00:00 Florian Westphal fw@strlen.de 2019-02-08T15:39:52+00:00 8303b7e8f018724a2cd7752eb29c2801fa8c4067 Sander Eikelenboom bisected a NAT related regression down to the l4proto->manip_pkt indirection removal. I forgot that ICMP(v6) errors (e.g. PKTTOOBIG) can be set as related to the existing conntrack entry. Therefore, when passing the skb to nf_nat_ipv4/6_manip_pkt(), that ended up calling the wrong l4 manip function, as tuple->dst.protonum is the original flows l4 protocol (TCP, UDP, etc). Set the dst protocol field to ICMP(v6), we already have a private copy of the tuple due to the inversion of src/dst. Reported-by: Sander Eikelenboom <linux@eikelenboom.it> Tested-by: Sander Eikelenboom <linux@eikelenboom.it> Fixes: faec18dbb0405 ("netfilter: nat: remove l4proto->manip_pkt") Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> 
Sander Eikelenboom bisected a NAT related regression down
to the l4proto->manip_pkt indirection removal.

I forgot that ICMP(v6) errors (e.g. PKTTOOBIG) can be set as related
to the existing conntrack entry.

Therefore, when passing the skb to nf_nat_ipv4/6_manip_pkt(), that
ended up calling the wrong l4 manip function, as tuple->dst.protonum
is the original flows l4 protocol (TCP, UDP, etc).

Set the dst protocol field to ICMP(v6), we already have a private copy
of the tuple due to the inversion of src/dst.

Reported-by: Sander Eikelenboom <linux@eikelenboom.it>
Tested-by: Sander Eikelenboom <linux@eikelenboom.it>
Fixes: faec18dbb0405 ("netfilter: nat: remove l4proto->manip_pkt")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
netfilter: nf_nat_snmp_basic: add missing length checks in ASN.1 cbs 2019-02-11T16:43:17+00:00 Jann Horn jannh@google.com 2019-02-06T21:56:15+00:00 c4c07b4d6fa1f11880eab8e076d3d060ef3f55fc The generic ASN.1 decoder infrastructure doesn't guarantee that callbacks will get as much data as they expect; callbacks have to check the `datalen` parameter before looking at `data`. Make sure that snmp_version() and snmp_helper() don't read/write beyond the end of the packet data. (Also move the assignment to `pdata` down below the check to make it clear that it isn't necessarily a pointer we can use before the `datalen` check.) Fixes: cc2d58634e0f ("netfilter: nf_nat_snmp_basic: use asn1 decoder library") Signed-off-by: Jann Horn <jannh@google.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> 
The generic ASN.1 decoder infrastructure doesn't guarantee that callbacks
will get as much data as they expect; callbacks have to check the `datalen`
parameter before looking at `data`. Make sure that snmp_version() and
snmp_helper() don't read/write beyond the end of the packet data.

(Also move the assignment to `pdata` down below the check to make it clear
that it isn't necessarily a pointer we can use before the `datalen` check.)

Fixes: cc2d58634e0f ("netfilter: nf_nat_snmp_basic: use asn1 decoder library")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
netfilter: ipt_CLUSTERIP: fix warning unused variable cn 2019-01-28T10:09:12+00:00 Anders Roxell anders.roxell@linaro.org 2019-01-23T11:48:11+00:00 206b8cc514d7ff2b79dd2d5ad939adc7c493f07a When CONFIG_PROC_FS isn't set the variable cn isn't used. net/ipv4/netfilter/ipt_CLUSTERIP.c: In function ‘clusterip_net_exit’: net/ipv4/netfilter/ipt_CLUSTERIP.c:849:24: warning: unused variable ‘cn’ [-Wunused-variable] struct clusterip_net *cn = clusterip_pernet(net); ^~ Rework so the variable 'cn' is declared inside "#ifdef CONFIG_PROC_FS". Fixes: b12f7bad5ad3 ("netfilter: ipt_CLUSTERIP: remove wrong WARN_ON_ONCE in netns exit routine") Signed-off-by: Anders Roxell <anders.roxell@linaro.org> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> 
When CONFIG_PROC_FS isn't set the variable cn isn't used.

net/ipv4/netfilter/ipt_CLUSTERIP.c: In function ‘clusterip_net_exit’:
net/ipv4/netfilter/ipt_CLUSTERIP.c:849:24: warning: unused variable ‘cn’ [-Wunused-variable]
  struct clusterip_net *cn = clusterip_pernet(net);
                        ^~

Rework so the variable 'cn' is declared inside "#ifdef CONFIG_PROC_FS".

Fixes: b12f7bad5ad3 ("netfilter: ipt_CLUSTERIP: remove wrong WARN_ON_ONCE in netns exit routine")
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next 2018-12-21T02:20:26+00:00 David S. Miller davem@davemloft.net 2018-12-21T02:20:26+00:00 c3e533692527046fb55020e7fac8c4272644ba45 Pablo Neira Ayuso says: ==================== Netfilter updates for net-next The following patchset contains Netfilter updates for net-next: 1) Support for destination MAC in ipset, from Stefano Brivio. 2) Disallow all-zeroes MAC address in ipset, also from Stefano. 3) Add IPSET_CMD_GET_BYNAME and IPSET_CMD_GET_BYINDEX commands, introduce protocol version number 7, from Jozsef Kadlecsik. A follow up patch to fix ip_set_byindex() is also included in this batch. 4) Honor CTA_MARK_MASK from ctnetlink, from Andreas Jaggi. 5) Statify nf_flow_table_iterate(), from Taehee Yoo. 6) Use nf_flow_table_iterate() to simplify garbage collection in nf_flow_table logic, also from Taehee Yoo. 7) Don't use _bh variants of call_rcu(), rcu_barrier() and synchronize_rcu_bh() in Netfilter, from Paul E. McKenney. 8) Remove NFC_* cache definition from the old caching infrastructure. 9) Remove layer 4 port rover in NAT helpers, use random port instead, from Florian Westphal. 10) Use strscpy() in ipset, from Qian Cai. 11) Remove NF_NAT_RANGE_PROTO_RANDOM_FULLY branch now that random port is allocated by default, from Xiaozhou Liu. 12) Ignore NF_NAT_RANGE_PROTO_RANDOM too, from Florian Westphal. 13) Limit port allocation selection routine in NAT to avoid softlockup splats when most ports are in use, from Florian. 14) Remove unused parameters in nf_ct_l4proto_unregister_sysctl() from Yafang Shao. 15) Direct call to nf_nat_l4proto_unique_tuple() instead of indirection, from Florian Westphal. 16) Several patches to remove all layer 4 NAT indirections, remove nf_nat_l4proto struct, from Florian Westphal. 17) Fix RTP/RTCP source port translation when SNAT is in place, from Alin Nastac. 18) Selective rule dump per chain, from Phil Sutter. 19) Revisit CLUSTERIP target, this includes a deadlock fix from netns path, sleep in atomic, remove bogus WARN_ON_ONCE() and disallow mismatching IP address and MAC address. Patchset from Taehee Yoo. 20) Update UDP timeout to stream after 2 seconds, from Florian. 21) Shrink UDP established timeout to 120 seconds like TCP timewait. 22) Sysctl knobs to set GRE timeouts, from Yafang Shao. 23) Move seq_print_acct() to conntrack core file, from Florian. 24) Add enum for conntrack sysctl knobs, also from Florian. 25) Place nf_conntrack_acct, nf_conntrack_helper, nf_conntrack_events and nf_conntrack_timestamp knobs in the core, from Florian Westphal. As a side effect, shrink netns_ct structure by removing obsolete sysctl anchors, also from Florian. ==================== Signed-off-by: David S. Miller <davem@davemloft.net> 
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for net-next:

1) Support for destination MAC in ipset, from Stefano Brivio.

2) Disallow all-zeroes MAC address in ipset, also from Stefano.

3) Add IPSET_CMD_GET_BYNAME and IPSET_CMD_GET_BYINDEX commands,
   introduce protocol version number 7, from Jozsef Kadlecsik.
   A follow up patch to fix ip_set_byindex() is also included
   in this batch.

4) Honor CTA_MARK_MASK from ctnetlink, from Andreas Jaggi.

5) Statify nf_flow_table_iterate(), from Taehee Yoo.

6) Use nf_flow_table_iterate() to simplify garbage collection in
   nf_flow_table logic, also from Taehee Yoo.

7) Don't use _bh variants of call_rcu(), rcu_barrier() and
   synchronize_rcu_bh() in Netfilter, from Paul E. McKenney.

8) Remove NFC_* cache definition from the old caching
   infrastructure.

9) Remove layer 4 port rover in NAT helpers, use random port
   instead, from Florian Westphal.

10) Use strscpy() in ipset, from Qian Cai.

11) Remove NF_NAT_RANGE_PROTO_RANDOM_FULLY branch now that
    random port is allocated by default, from Xiaozhou Liu.

12) Ignore NF_NAT_RANGE_PROTO_RANDOM too, from Florian Westphal.

13) Limit port allocation selection routine in NAT to avoid
    softlockup splats when most ports are in use, from Florian.

14) Remove unused parameters in nf_ct_l4proto_unregister_sysctl()
    from Yafang Shao.

15) Direct call to nf_nat_l4proto_unique_tuple() instead of
    indirection, from Florian Westphal.

16) Several patches to remove all layer 4 NAT indirections,
    remove nf_nat_l4proto struct, from Florian Westphal.

17) Fix RTP/RTCP source port translation when SNAT is in place,
    from Alin Nastac.

18) Selective rule dump per chain, from Phil Sutter.

19) Revisit CLUSTERIP target, this includes a deadlock fix from
    netns path, sleep in atomic, remove bogus WARN_ON_ONCE()
    and disallow mismatching IP address and MAC address.
    Patchset from Taehee Yoo.

20) Update UDP timeout to stream after 2 seconds, from Florian.

21) Shrink UDP established timeout to 120 seconds like TCP timewait.

22) Sysctl knobs to set GRE timeouts, from Yafang Shao.

23) Move seq_print_acct() to conntrack core file, from Florian.

24) Add enum for conntrack sysctl knobs, also from Florian.

25) Place nf_conntrack_acct, nf_conntrack_helper, nf_conntrack_events
    and nf_conntrack_timestamp knobs in the core, from Florian Westphal.
    As a side effect, shrink netns_ct structure by removing obsolete
    sysctl anchors, also from Florian.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
netfilter: avoid using skb->nf_bridge directly 2018-12-19T19:21:37+00:00 Florian Westphal fw@strlen.de 2018-12-18T16:15:15+00:00 c4b0e771f906f5beb7d90c3d28fe55ff9dbd038c This pointer is going to be removed soon, so use the existing helpers in more places to avoid noise when the removal happens. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net> 
This pointer is going to be removed soon, so use the existing helpers in
more places to avoid noise when the removal happens.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
netfilter: ipt_CLUSTERIP: check MAC address when duplicate config is set 2018-12-18T00:18:38+00:00 Taehee Yoo ap420073@gmail.com 2018-11-05T09:23:25+00:00 06aa151ad1fc74a49b45336672515774a678d78d If same destination IP address config is already existing, that config is just used. MAC address also should be same. However, there is no MAC address checking routine. So that MAC address checking routine is added. test commands: %iptables -A INPUT -p tcp -i lo -d 192.168.0.5 --dport 80 \ -j CLUSTERIP --new --hashmode sourceip \ --clustermac 01:00:5e:00:00:20 --total-nodes 2 --local-node 1 %iptables -A INPUT -p tcp -i lo -d 192.168.0.5 --dport 80 \ -j CLUSTERIP --new --hashmode sourceip \ --clustermac 01:00:5e:00:00:21 --total-nodes 2 --local-node 1 After this patch, above commands are disallowed. Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> 
If same destination IP address config is already existing, that config is
just used. MAC address also should be same.
However, there is no MAC address checking routine.
So that MAC address checking routine is added.

test commands:
   %iptables -A INPUT -p tcp -i lo -d 192.168.0.5 --dport 80 \
	   -j CLUSTERIP --new --hashmode sourceip \
	   --clustermac 01:00:5e:00:00:20 --total-nodes 2 --local-node 1
   %iptables -A INPUT -p tcp -i lo -d 192.168.0.5 --dport 80 \
	   -j CLUSTERIP --new --hashmode sourceip \
	   --clustermac 01:00:5e:00:00:21 --total-nodes 2 --local-node 1

After this patch, above commands are disallowed.

Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
netfilter: ipt_CLUSTERIP: fix sleep-in-atomic bug in clusterip_config_entry_put() 2018-12-18T00:18:24+00:00 Taehee Yoo ap420073@gmail.com 2018-11-05T09:23:13+00:00 2a61d8b883bbad26b06d2e6cc3777a697e78830d A proc_remove() can sleep. so that it can't be inside of spin_lock. Hence proc_remove() is moved to outside of spin_lock. and it also adds mutex to sync create and remove of proc entry(config->pde). test commands: SHELL#1 %while :; do iptables -A INPUT -p udp -i enp2s0 -d 192.168.1.100 \ --dport 9000 -j CLUSTERIP --new --hashmode sourceip \ --clustermac 01:00:5e:00:00:21 --total-nodes 3 --local-node 3; \ iptables -F; done SHELL#2 %while :; do echo +1 > /proc/net/ipt_CLUSTERIP/192.168.1.100; \ echo -1 > /proc/net/ipt_CLUSTERIP/192.168.1.100; done [ 2949.569864] BUG: sleeping function called from invalid context at kernel/sched/completion.c:99 [ 2949.579944] in_atomic(): 1, irqs_disabled(): 0, pid: 5472, name: iptables [ 2949.587920] 1 lock held by iptables/5472: [ 2949.592711] #0: 000000008f0ebcf2 (&(&cn->lock)->rlock){+...}, at: refcount_dec_and_lock+0x24/0x50 [ 2949.603307] CPU: 1 PID: 5472 Comm: iptables Tainted: G W 4.19.0-rc5+ #16 [ 2949.604212] Hardware name: To be filled by O.E.M. To be filled by O.E.M./Aptio CRB, BIOS 5.6.5 07/08/2015 [ 2949.604212] Call Trace: [ 2949.604212] dump_stack+0xc9/0x16b [ 2949.604212] ? show_regs_print_info+0x5/0x5 [ 2949.604212] ___might_sleep+0x2eb/0x420 [ 2949.604212] ? set_rq_offline.part.87+0x140/0x140 [ 2949.604212] ? _rcu_barrier_trace+0x400/0x400 [ 2949.604212] wait_for_completion+0x94/0x710 [ 2949.604212] ? wait_for_completion_interruptible+0x780/0x780 [ 2949.604212] ? __kernel_text_address+0xe/0x30 [ 2949.604212] ? __lockdep_init_map+0x10e/0x5c0 [ 2949.604212] ? __lockdep_init_map+0x10e/0x5c0 [ 2949.604212] ? __init_waitqueue_head+0x86/0x130 [ 2949.604212] ? init_wait_entry+0x1a0/0x1a0 [ 2949.604212] proc_entry_rundown+0x208/0x270 [ 2949.604212] ? proc_reg_get_unmapped_area+0x370/0x370 [ 2949.604212] ? __lock_acquire+0x4500/0x4500 [ 2949.604212] ? complete+0x18/0x70 [ 2949.604212] remove_proc_subtree+0x143/0x2a0 [ 2949.708655] ? remove_proc_entry+0x390/0x390 [ 2949.708655] clusterip_tg_destroy+0x27a/0x630 [ipt_CLUSTERIP] [ ... ] Fixes: b3e456fce9f5 ("netfilter: ipt_CLUSTERIP: fix a race condition of proc file creation") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> 
A proc_remove() can sleep. so that it can't be inside of spin_lock.
Hence proc_remove() is moved to outside of spin_lock. and it also
adds mutex to sync create and remove of proc entry(config->pde).

test commands:
SHELL#1
   %while :; do iptables -A INPUT -p udp -i enp2s0 -d 192.168.1.100 \
	   --dport 9000  -j CLUSTERIP --new --hashmode sourceip \
	   --clustermac 01:00:5e:00:00:21 --total-nodes 3 --local-node 3; \
	   iptables -F; done

SHELL#2
   %while :; do echo +1 > /proc/net/ipt_CLUSTERIP/192.168.1.100; \
	   echo -1 > /proc/net/ipt_CLUSTERIP/192.168.1.100; done

[ 2949.569864] BUG: sleeping function called from invalid context at kernel/sched/completion.c:99
[ 2949.579944] in_atomic(): 1, irqs_disabled(): 0, pid: 5472, name: iptables
[ 2949.587920] 1 lock held by iptables/5472:
[ 2949.592711]  #0: 000000008f0ebcf2 (&(&cn->lock)->rlock){+...}, at: refcount_dec_and_lock+0x24/0x50
[ 2949.603307] CPU: 1 PID: 5472 Comm: iptables Tainted: G        W         4.19.0-rc5+ #16
[ 2949.604212] Hardware name: To be filled by O.E.M. To be filled by O.E.M./Aptio CRB, BIOS 5.6.5 07/08/2015
[ 2949.604212] Call Trace:
[ 2949.604212]  dump_stack+0xc9/0x16b
[ 2949.604212]  ? show_regs_print_info+0x5/0x5
[ 2949.604212]  ___might_sleep+0x2eb/0x420
[ 2949.604212]  ? set_rq_offline.part.87+0x140/0x140
[ 2949.604212]  ? _rcu_barrier_trace+0x400/0x400
[ 2949.604212]  wait_for_completion+0x94/0x710
[ 2949.604212]  ? wait_for_completion_interruptible+0x780/0x780
[ 2949.604212]  ? __kernel_text_address+0xe/0x30
[ 2949.604212]  ? __lockdep_init_map+0x10e/0x5c0
[ 2949.604212]  ? __lockdep_init_map+0x10e/0x5c0
[ 2949.604212]  ? __init_waitqueue_head+0x86/0x130
[ 2949.604212]  ? init_wait_entry+0x1a0/0x1a0
[ 2949.604212]  proc_entry_rundown+0x208/0x270
[ 2949.604212]  ? proc_reg_get_unmapped_area+0x370/0x370
[ 2949.604212]  ? __lock_acquire+0x4500/0x4500
[ 2949.604212]  ? complete+0x18/0x70
[ 2949.604212]  remove_proc_subtree+0x143/0x2a0
[ 2949.708655]  ? remove_proc_entry+0x390/0x390
[ 2949.708655]  clusterip_tg_destroy+0x27a/0x630 [ipt_CLUSTERIP]
[ ... ]

Fixes: b3e456fce9f5 ("netfilter: ipt_CLUSTERIP: fix a race condition of proc file creation")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
netfilter: ipt_CLUSTERIP: remove wrong WARN_ON_ONCE in netns exit routine 2018-12-18T00:18:09+00:00 Taehee Yoo ap420073@gmail.com 2018-11-05T09:22:55+00:00 b12f7bad5ad3724d19754390a3e80928525c0769 When network namespace is destroyed, both clusterip_tg_destroy() and clusterip_net_exit() are called. and clusterip_net_exit() is called before clusterip_tg_destroy(). Hence cleanup check code in clusterip_net_exit() doesn't make sense. test commands: %ip netns add vm1 %ip netns exec vm1 bash %ip link set lo up %iptables -A INPUT -p tcp -i lo -d 192.168.0.5 --dport 80 \ -j CLUSTERIP --new --hashmode sourceip \ --clustermac 01:00:5e:00:00:20 --total-nodes 2 --local-node 1 %exit %ip netns del vm1 splat looks like: [ 341.184508] WARNING: CPU: 1 PID: 87 at net/ipv4/netfilter/ipt_CLUSTERIP.c:840 clusterip_net_exit+0x319/0x380 [ipt_CLUSTERIP] [ 341.184850] Modules linked in: ipt_CLUSTERIP nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 xt_tcpudp iptable_filter bpfilter ip_tables x_tables [ 341.184850] CPU: 1 PID: 87 Comm: kworker/u4:2 Not tainted 4.19.0-rc5+ #16 [ 341.227509] Workqueue: netns cleanup_net [ 341.227509] RIP: 0010:clusterip_net_exit+0x319/0x380 [ipt_CLUSTERIP] [ 341.227509] Code: 0f 85 7f fe ff ff 48 c7 c2 80 64 2c c0 be a8 02 00 00 48 c7 c7 a0 63 2c c0 c6 05 18 6e 00 00 01 e8 bc 38 ff f5 e9 5b fe ff ff <0f> 0b e9 33 ff ff ff e8 4b 90 50 f6 e9 2d fe ff ff 48 89 df e8 de [ 341.227509] RSP: 0018:ffff88011086f408 EFLAGS: 00010202 [ 341.227509] RAX: dffffc0000000000 RBX: 1ffff1002210de85 RCX: 0000000000000000 [ 341.227509] RDX: 1ffff1002210de85 RSI: ffff880110813be8 RDI: ffffed002210de58 [ 341.227509] RBP: ffff88011086f4d0 R08: 0000000000000000 R09: 0000000000000000 [ 341.227509] R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff1002210de81 [ 341.227509] R13: ffff880110625a48 R14: ffff880114cec8c8 R15: 0000000000000014 [ 341.227509] FS: 0000000000000000(0000) GS:ffff880116600000(0000) knlGS:0000000000000000 [ 341.227509] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 341.227509] CR2: 00007f11fd38e000 CR3: 000000013ca16000 CR4: 00000000001006e0 [ 341.227509] Call Trace: [ 341.227509] ? __clusterip_config_find+0x460/0x460 [ipt_CLUSTERIP] [ 341.227509] ? default_device_exit+0x1ca/0x270 [ 341.227509] ? remove_proc_entry+0x1cd/0x390 [ 341.227509] ? dev_change_net_namespace+0xd00/0xd00 [ 341.227509] ? __init_waitqueue_head+0x130/0x130 [ 341.227509] ops_exit_list.isra.10+0x94/0x140 [ 341.227509] cleanup_net+0x45b/0x900 [ ... ] Fixes: 613d0776d3fe ("netfilter: exit_net cleanup check added") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> 
When network namespace is destroyed, both clusterip_tg_destroy() and
clusterip_net_exit() are called. and clusterip_net_exit() is called
before clusterip_tg_destroy().
Hence cleanup check code in clusterip_net_exit() doesn't make sense.

test commands:
   %ip netns add vm1
   %ip netns exec vm1 bash
   %ip link set lo up
   %iptables -A INPUT -p tcp -i lo -d 192.168.0.5 --dport 80 \
	-j CLUSTERIP --new --hashmode sourceip \
	--clustermac 01:00:5e:00:00:20 --total-nodes 2 --local-node 1
   %exit
   %ip netns del vm1

splat looks like:
[  341.184508] WARNING: CPU: 1 PID: 87 at net/ipv4/netfilter/ipt_CLUSTERIP.c:840 clusterip_net_exit+0x319/0x380 [ipt_CLUSTERIP]
[  341.184850] Modules linked in: ipt_CLUSTERIP nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 xt_tcpudp iptable_filter bpfilter ip_tables x_tables
[  341.184850] CPU: 1 PID: 87 Comm: kworker/u4:2 Not tainted 4.19.0-rc5+ #16
[  341.227509] Workqueue: netns cleanup_net
[  341.227509] RIP: 0010:clusterip_net_exit+0x319/0x380 [ipt_CLUSTERIP]
[  341.227509] Code: 0f 85 7f fe ff ff 48 c7 c2 80 64 2c c0 be a8 02 00 00 48 c7 c7 a0 63 2c c0 c6 05 18 6e 00 00 01 e8 bc 38 ff f5 e9 5b fe ff ff <0f> 0b e9 33 ff ff ff e8 4b 90 50 f6 e9 2d fe ff ff 48 89 df e8 de
[  341.227509] RSP: 0018:ffff88011086f408 EFLAGS: 00010202
[  341.227509] RAX: dffffc0000000000 RBX: 1ffff1002210de85 RCX: 0000000000000000
[  341.227509] RDX: 1ffff1002210de85 RSI: ffff880110813be8 RDI: ffffed002210de58
[  341.227509] RBP: ffff88011086f4d0 R08: 0000000000000000 R09: 0000000000000000
[  341.227509] R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff1002210de81
[  341.227509] R13: ffff880110625a48 R14: ffff880114cec8c8 R15: 0000000000000014
[  341.227509] FS:  0000000000000000(0000) GS:ffff880116600000(0000) knlGS:0000000000000000
[  341.227509] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  341.227509] CR2: 00007f11fd38e000 CR3: 000000013ca16000 CR4: 00000000001006e0
[  341.227509] Call Trace:
[  341.227509]  ? __clusterip_config_find+0x460/0x460 [ipt_CLUSTERIP]
[  341.227509]  ? default_device_exit+0x1ca/0x270
[  341.227509]  ? remove_proc_entry+0x1cd/0x390
[  341.227509]  ? dev_change_net_namespace+0xd00/0xd00
[  341.227509]  ? __init_waitqueue_head+0x130/0x130
[  341.227509]  ops_exit_list.isra.10+0x94/0x140
[  341.227509]  cleanup_net+0x45b/0x900
[ ... ]

Fixes: 613d0776d3fe ("netfilter: exit_net cleanup check added")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
netfilter: ipt_CLUSTERIP: fix deadlock in netns exit routine 2018-12-18T00:17:59+00:00 Taehee Yoo ap420073@gmail.com 2018-11-05T09:22:44+00:00 5a86d68bcf02f2d1e9a5897dd482079fd5f75e7f When network namespace is destroyed, cleanup_net() is called. cleanup_net() holds pernet_ops_rwsem then calls each ->exit callback. So that clusterip_tg_destroy() is called by cleanup_net(). And clusterip_tg_destroy() calls unregister_netdevice_notifier(). But both cleanup_net() and clusterip_tg_destroy() hold same lock(pernet_ops_rwsem). hence deadlock occurrs. After this patch, only 1 notifier is registered when module is inserted. And all of configs are added to per-net list. test commands: %ip netns add vm1 %ip netns exec vm1 bash %ip link set lo up %iptables -A INPUT -p tcp -i lo -d 192.168.0.5 --dport 80 \ -j CLUSTERIP --new --hashmode sourceip \ --clustermac 01:00:5e:00:00:20 --total-nodes 2 --local-node 1 %exit %ip netns del vm1 splat looks like: [ 341.809674] ============================================ [ 341.809674] WARNING: possible recursive locking detected [ 341.809674] 4.19.0-rc5+ #16 Tainted: G W [ 341.809674] -------------------------------------------- [ 341.809674] kworker/u4:2/87 is trying to acquire lock: [ 341.809674] 000000005da2d519 (pernet_ops_rwsem){++++}, at: unregister_netdevice_notifier+0x8c/0x460 [ 341.809674] [ 341.809674] but task is already holding lock: [ 341.809674] 000000005da2d519 (pernet_ops_rwsem){++++}, at: cleanup_net+0x119/0x900 [ 341.809674] [ 341.809674] other info that might help us debug this: [ 341.809674] Possible unsafe locking scenario: [ 341.809674] [ 341.809674] CPU0 [ 341.809674] ---- [ 341.809674] lock(pernet_ops_rwsem); [ 341.809674] lock(pernet_ops_rwsem); [ 341.809674] [ 341.809674] *** DEADLOCK *** [ 341.809674] [ 341.809674] May be due to missing lock nesting notation [ 341.809674] [ 341.809674] 3 locks held by kworker/u4:2/87: [ 341.809674] #0: 00000000d9df6c92 ((wq_completion)"%s""netns"){+.+.}, at: process_one_work+0xafe/0x1de0 [ 341.809674] #1: 00000000c2cbcee2 (net_cleanup_work){+.+.}, at: process_one_work+0xb60/0x1de0 [ 341.809674] #2: 000000005da2d519 (pernet_ops_rwsem){++++}, at: cleanup_net+0x119/0x900 [ 341.809674] [ 341.809674] stack backtrace: [ 341.809674] CPU: 1 PID: 87 Comm: kworker/u4:2 Tainted: G W 4.19.0-rc5+ #16 [ 341.809674] Workqueue: netns cleanup_net [ 341.809674] Call Trace: [ ... ] [ 342.070196] down_write+0x93/0x160 [ 342.070196] ? unregister_netdevice_notifier+0x8c/0x460 [ 342.070196] ? down_read+0x1e0/0x1e0 [ 342.070196] ? sched_clock_cpu+0x126/0x170 [ 342.070196] ? find_held_lock+0x39/0x1c0 [ 342.070196] unregister_netdevice_notifier+0x8c/0x460 [ 342.070196] ? register_netdevice_notifier+0x790/0x790 [ 342.070196] ? __local_bh_enable_ip+0xe9/0x1b0 [ 342.070196] ? __local_bh_enable_ip+0xe9/0x1b0 [ 342.070196] ? clusterip_tg_destroy+0x372/0x650 [ipt_CLUSTERIP] [ 342.070196] ? trace_hardirqs_on+0x93/0x210 [ 342.070196] ? __bpf_trace_preemptirq_template+0x10/0x10 [ 342.070196] ? clusterip_tg_destroy+0x372/0x650 [ipt_CLUSTERIP] [ 342.123094] clusterip_tg_destroy+0x3ad/0x650 [ipt_CLUSTERIP] [ 342.123094] ? clusterip_net_init+0x3d0/0x3d0 [ipt_CLUSTERIP] [ 342.123094] ? cleanup_match+0x17d/0x200 [ip_tables] [ 342.123094] ? xt_unregister_table+0x215/0x300 [x_tables] [ 342.123094] ? kfree+0xe2/0x2a0 [ 342.123094] cleanup_entry+0x1d5/0x2f0 [ip_tables] [ 342.123094] ? cleanup_match+0x200/0x200 [ip_tables] [ 342.123094] __ipt_unregister_table+0x9b/0x1a0 [ip_tables] [ 342.123094] iptable_filter_net_exit+0x43/0x80 [iptable_filter] [ 342.123094] ops_exit_list.isra.10+0x94/0x140 [ 342.123094] cleanup_net+0x45b/0x900 [ ... ] Fixes: 202f59afd441 ("netfilter: ipt_CLUSTERIP: do not hold dev") Signed-off-by: Taehee Yoo <ap420073@gmail.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> 
When network namespace is destroyed, cleanup_net() is called.
cleanup_net() holds pernet_ops_rwsem then calls each ->exit callback.
So that clusterip_tg_destroy() is called by cleanup_net().
And clusterip_tg_destroy() calls unregister_netdevice_notifier().

But both cleanup_net() and clusterip_tg_destroy() hold same
lock(pernet_ops_rwsem). hence deadlock occurrs.

After this patch, only 1 notifier is registered when module is inserted.
And all of configs are added to per-net list.

test commands:
   %ip netns add vm1
   %ip netns exec vm1 bash
   %ip link set lo up
   %iptables -A INPUT -p tcp -i lo -d 192.168.0.5 --dport 80 \
	-j CLUSTERIP --new --hashmode sourceip \
	--clustermac 01:00:5e:00:00:20 --total-nodes 2 --local-node 1
   %exit
   %ip netns del vm1

splat looks like:
[  341.809674] ============================================
[  341.809674] WARNING: possible recursive locking detected
[  341.809674] 4.19.0-rc5+ #16 Tainted: G        W
[  341.809674] --------------------------------------------
[  341.809674] kworker/u4:2/87 is trying to acquire lock:
[  341.809674] 000000005da2d519 (pernet_ops_rwsem){++++}, at: unregister_netdevice_notifier+0x8c/0x460
[  341.809674]
[  341.809674] but task is already holding lock:
[  341.809674] 000000005da2d519 (pernet_ops_rwsem){++++}, at: cleanup_net+0x119/0x900
[  341.809674]
[  341.809674] other info that might help us debug this:
[  341.809674]  Possible unsafe locking scenario:
[  341.809674]
[  341.809674]        CPU0
[  341.809674]        ----
[  341.809674]   lock(pernet_ops_rwsem);
[  341.809674]   lock(pernet_ops_rwsem);
[  341.809674]
[  341.809674]  *** DEADLOCK ***
[  341.809674]
[  341.809674]  May be due to missing lock nesting notation
[  341.809674]
[  341.809674] 3 locks held by kworker/u4:2/87:
[  341.809674]  #0: 00000000d9df6c92 ((wq_completion)"%s""netns"){+.+.}, at: process_one_work+0xafe/0x1de0
[  341.809674]  #1: 00000000c2cbcee2 (net_cleanup_work){+.+.}, at: process_one_work+0xb60/0x1de0
[  341.809674]  #2: 000000005da2d519 (pernet_ops_rwsem){++++}, at: cleanup_net+0x119/0x900
[  341.809674]
[  341.809674] stack backtrace:
[  341.809674] CPU: 1 PID: 87 Comm: kworker/u4:2 Tainted: G        W         4.19.0-rc5+ #16
[  341.809674] Workqueue: netns cleanup_net
[  341.809674] Call Trace:
[ ... ]
[  342.070196]  down_write+0x93/0x160
[  342.070196]  ? unregister_netdevice_notifier+0x8c/0x460
[  342.070196]  ? down_read+0x1e0/0x1e0
[  342.070196]  ? sched_clock_cpu+0x126/0x170
[  342.070196]  ? find_held_lock+0x39/0x1c0
[  342.070196]  unregister_netdevice_notifier+0x8c/0x460
[  342.070196]  ? register_netdevice_notifier+0x790/0x790
[  342.070196]  ? __local_bh_enable_ip+0xe9/0x1b0
[  342.070196]  ? __local_bh_enable_ip+0xe9/0x1b0
[  342.070196]  ? clusterip_tg_destroy+0x372/0x650 [ipt_CLUSTERIP]
[  342.070196]  ? trace_hardirqs_on+0x93/0x210
[  342.070196]  ? __bpf_trace_preemptirq_template+0x10/0x10
[  342.070196]  ? clusterip_tg_destroy+0x372/0x650 [ipt_CLUSTERIP]
[  342.123094]  clusterip_tg_destroy+0x3ad/0x650 [ipt_CLUSTERIP]
[  342.123094]  ? clusterip_net_init+0x3d0/0x3d0 [ipt_CLUSTERIP]
[  342.123094]  ? cleanup_match+0x17d/0x200 [ip_tables]
[  342.123094]  ? xt_unregister_table+0x215/0x300 [x_tables]
[  342.123094]  ? kfree+0xe2/0x2a0
[  342.123094]  cleanup_entry+0x1d5/0x2f0 [ip_tables]
[  342.123094]  ? cleanup_match+0x200/0x200 [ip_tables]
[  342.123094]  __ipt_unregister_table+0x9b/0x1a0 [ip_tables]
[  342.123094]  iptable_filter_net_exit+0x43/0x80 [iptable_filter]
[  342.123094]  ops_exit_list.isra.10+0x94/0x140
[  342.123094]  cleanup_net+0x45b/0x900
[ ... ]

Fixes: 202f59afd441 ("netfilter: ipt_CLUSTERIP: do not hold dev")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
netfilter: nat: remove nf_nat_l4proto struct 2018-12-17T22:33:31+00:00 Florian Westphal fw@strlen.de 2018-12-13T15:01:34+00:00 5cbabeec1eb758233b35683123de446a57852932 This removes the (now empty) nf_nat_l4proto struct, all its instances and all the no longer needed runtime (un)register functionality. nf_nat_need_gre() can be axed as well: the module that calls it (to load the no-longer-existing nat_gre module) also calls other nat core functions. GRE nat is now always available if kernel is built with it. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> 
This removes the (now empty) nf_nat_l4proto struct, all its instances
and all the no longer needed runtime (un)register functionality.

nf_nat_need_gre() can be axed as well: the module that calls it (to
load the no-longer-existing nat_gre module) also calls other nat core
functions. GRE nat is now always available if kernel is built with it.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>