linux.git/net/netfilter, branch v4.19

netfilter: xt_socket: check sk before checking for netns.

2018-09-28T12:47:41+00:00

Only check for the network namespace if the socket is available.

Fixes: f564650106a6 ("netfilter: check if the socket netns is correct.")
Reported-by: Guenter Roeck 
Tested-by: Guenter Roeck 
Signed-off-by: Flavio Leitner 
Signed-off-by: Pablo Neira Ayuso

netfilter: nft_set_rbtree: add missing rb_erase() in GC routine

2018-09-28T12:47:01+00:00

The nft_set_gc_batch_check() checks whether gc buffer is full.
If gc buffer is full, gc buffer is released by
the nft_set_gc_batch_complete() internally.
In case of rbtree, the rb_erase() should be called before calling the
nft_set_gc_batch_complete(). therefore the rb_erase() should
be called before calling the nft_set_gc_batch_check() too.

test commands:
   table ip filter {
	   set set1 {
		   type ipv4_addr; flags interval, timeout;
		   gc-interval 10s;
		   timeout 1s;
		   elements = {
			   1-2,
			   3-4,
			   5-6,
			   ...
			   10000-10001,
		   }
	   }
   }
   %nft -f test.nft

splat looks like:
[  430.273885] kasan: GPF could be caused by NULL-ptr deref or user memory access
[  430.282158] general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI
[  430.283116] CPU: 1 PID: 190 Comm: kworker/1:2 Tainted: G    B             4.18.0+ #7
[  430.283116] Workqueue: events_power_efficient nft_rbtree_gc [nf_tables_set]
[  430.313559] RIP: 0010:rb_next+0x81/0x130
[  430.313559] Code: 08 49 bd 00 00 00 00 00 fc ff df 48 bb 00 00 00 00 00 fc ff df 48 85 c0 75 05 eb 58 48 89 d4
[  430.313559] RSP: 0018:ffff88010cdb7680 EFLAGS: 00010207
[  430.313559] RAX: 0000000000b84854 RBX: dffffc0000000000 RCX: ffffffff83f01973
[  430.313559] RDX: 000000000017090c RSI: 0000000000000008 RDI: 0000000000b84864
[  430.313559] RBP: ffff8801060d4588 R08: fffffbfff09bc349 R09: fffffbfff09bc349
[  430.313559] R10: 0000000000000001 R11: fffffbfff09bc348 R12: ffff880100f081a8
[  430.313559] R13: dffffc0000000000 R14: ffff880100ff8688 R15: dffffc0000000000
[  430.313559] FS:  0000000000000000(0000) GS:ffff88011b400000(0000) knlGS:0000000000000000
[  430.313559] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  430.313559] CR2: 0000000001551008 CR3: 000000005dc16000 CR4: 00000000001006e0
[  430.313559] Call Trace:
[  430.313559]  nft_rbtree_gc+0x112/0x5c0 [nf_tables_set]
[  430.313559]  process_one_work+0xc13/0x1ec0
[  430.313559]  ? _raw_spin_unlock_irq+0x29/0x40
[  430.313559]  ? pwq_dec_nr_in_flight+0x3c0/0x3c0
[  430.313559]  ? set_load_weight+0x270/0x270
[  430.313559]  ? __switch_to_asm+0x34/0x70
[  430.313559]  ? __switch_to_asm+0x40/0x70
[  430.313559]  ? __switch_to_asm+0x34/0x70
[  430.313559]  ? __switch_to_asm+0x34/0x70
[  430.313559]  ? __switch_to_asm+0x40/0x70
[  430.313559]  ? __switch_to_asm+0x34/0x70
[  430.313559]  ? __switch_to_asm+0x40/0x70
[  430.313559]  ? __switch_to_asm+0x34/0x70
[  430.313559]  ? __switch_to_asm+0x34/0x70
[  430.313559]  ? __switch_to_asm+0x40/0x70
[  430.313559]  ? __switch_to_asm+0x34/0x70
[  430.313559]  ? __schedule+0x6d3/0x1f50
[  430.313559]  ? find_held_lock+0x39/0x1c0
[  430.313559]  ? __sched_text_start+0x8/0x8
[  430.313559]  ? cyc2ns_read_end+0x10/0x10
[  430.313559]  ? save_trace+0x300/0x300
[  430.313559]  ? sched_clock_local+0xd4/0x140
[  430.313559]  ? find_held_lock+0x39/0x1c0
[  430.313559]  ? worker_thread+0x353/0x1120
[  430.313559]  ? worker_thread+0x353/0x1120
[  430.313559]  ? lock_contended+0xe70/0xe70
[  430.313559]  ? __lock_acquire+0x4500/0x4500
[  430.535635]  ? do_raw_spin_unlock+0xa5/0x330
[  430.535635]  ? do_raw_spin_trylock+0x101/0x1a0
[  430.535635]  ? do_raw_spin_lock+0x1f0/0x1f0
[  430.535635]  ? _raw_spin_lock_irq+0x10/0x70
[  430.535635]  worker_thread+0x15d/0x1120
[ ... ]

Fixes: 8d8540c4f5e0 ("netfilter: nft_set_rbtree: add timeout support")
Signed-off-by: Taehee Yoo 
Signed-off-by: Pablo Neira Ayuso

netfilter: conntrack: get rid of double sizeof

2018-09-20T16:40:32+00:00

sizeof(sizeof()) is quite strange and does not seem to be what
is wanted here.

The issue is detected with the help of Coccinelle.

Fixes: 39215846740a ("netfilter: conntrack: remove nlattr_size pointer from l4proto trackers")
Signed-off-by: zhong jiang 
Acked-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso

netfilter: nft_osf: use enum nft_data_types for nft_validate_register_store

2018-09-20T16:38:40+00:00

The function nft_validate_register_store requires a struct of type
struct nft_data_types. NFTA_DATA_VALUE is of type enum
nft_verdict_attributes. Pass the correct enum type.

This fixes a warning seen with Clang:
  net/netfilter/nft_osf.c:52:8: warning: implicit conversion from
    enumeration type 'enum nft_data_attributes' to different enumeration
    type 'enum nft_data_types' [-Wenum-conversion]
                                          NFTA_DATA_VALUE, NFT_OSF_MAXGENRELEN);
                                          ^~~~~~~~~~~~~~~

Fixes: b96af92d6eaf ("netfilter: nf_tables: implement Passive OS fingerprint module in nft_osf")
Link: https://github.com/ClangBuiltLinux/linux/issues/103
Signed-off-by: Stefan Agner 
Signed-off-by: Pablo Neira Ayuso

Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf

2018-09-12T04:17:30+00:00

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for you net tree:

1) Remove duplicated include at the end of UDP conntrack, from Yue Haibing.

2) Restore conntrack dependency on xt_cluster, from Martin Willi.

3) Fix splat with GSO skbs from the checksum target, from Florian Westphal.

4) Rework ct timeout support, the template strategy to attach custom timeouts
   is not correct since it will not work in conjunction with conntrack zones
   and we have a possible free after use when removing the rule due to missing
   refcounting. To fix these problems, do not use conntrack template at all
   and set custom timeout on the already valid conntrack object. This
   fix comes with a preparation patch to simplify timeout adjustment by
   initializating the first position of the timeout array for all of the
   existing trackers. Patchset from Florian Westphal.

5) Fix missing dependency on from IPv4 chain NAT type, from Florian.

6) Release chain reference counter from the flush path, from Taehee Yoo.

7) After flushing an iptables ruleset, conntrack hooks are unregistered
   and entries are left stale to be cleaned up by the timeout garbage
   collector. No TCP tracking is done on established flows by this time.
   If ruleset is reloaded, then hooks are registered again and TCP
   tracking is restored, which considers packets to be invalid. Clear
   window tracking to exercise TCP flow pickup from the middle given that
   history is lost for us. Again from Florian.

8) Fix crash from netlink interface with CONFIG_NF_CONNTRACK_TIMEOUT=y
   and CONFIG_NF_CT_NETLINK_TIMEOUT=n.

9) Broken CT target due to returning incorrect type from
   ctnl_timeout_find_get().

10) Solve conntrack clash on NF_REPEAT verdicts too, from Michal Vaner.

11) Missing conversion of hashlimit sysctl interface to new API, from
    Cong Wang.
====================

Signed-off-by: David S. Miller

netfilter: xt_hashlimit: use s->file instead of s->private

2018-09-10T23:35:32+00:00

After switching to the new procfs API, it is supposed to
retrieve the private pointer from PDE_DATA(file_inode(s->file)),
s->private is no longer referred.

Fixes: 1cd671827290 ("netfilter/x_tables: switch to proc_create_seq_private")
Reported-by: Sami Farin 
Signed-off-by: Cong Wang 
Acked-by: Christoph Hellwig 
Tested-by: Sami Farin 
Signed-off-by: Pablo Neira Ayuso

netfilter: nfnetlink_queue: Solve the NFQUEUE/conntrack clash for NF_REPEAT

2018-09-10T23:31:47+00:00

NF_REPEAT places the packet at the beginning of the iptables chain
instead of accepting or rejecting it right away. The packet however will
reach the end of the chain and continue to the end of iptables
eventually, so it needs the same handling as NF_ACCEPT and NF_DROP.

Fixes: 368982cd7d1b ("netfilter: nfnetlink_queue: resolve clash for unconfirmed conntracks")
Signed-off-by: Michal 'vorner' Vaner 
Signed-off-by: Pablo Neira Ayuso

netfilter: cttimeout: ctnl_timeout_find_get() returns incorrect pointer to type

2018-09-10T23:31:10+00:00

Compiler did not catch incorrect typing in the rcu hook assignment.

 % nfct add timeout test-tcp inet tcp established 100 close 10 close_wait 10
 % iptables -I OUTPUT -t raw -p tcp -j CT --timeout test-tcp
 dmesg - xt_CT: Timeout policy `test-tcp' can only be used by L3 protocol number 25000

The CT target bails out with incorrect layer 3 protocol number.

Fixes: 6c1fd7dc489d ("netfilter: cttimeout: decouple timeout policy from nfnetlink_cttimeout object")
Reported-by: Harsha Sharma 
Signed-off-by: Pablo Neira Ayuso

netfilter: conntrack: timeout interface depend on CONFIG_NF_CONNTRACK_TIMEOUT

2018-09-10T23:30:25+00:00

Now that cttimeout support for nft_ct is in place, these should depend
on CONFIG_NF_CONNTRACK_TIMEOUT otherwise we can crash when dumping the
policy if this option is not enabled.

[   71.600121] BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
[...]
[   71.600141] CPU: 3 PID: 7612 Comm: nft Not tainted 4.18.0+ #246
[...]
[   71.600188] Call Trace:
[   71.600201]  ? nft_ct_timeout_obj_dump+0xc6/0xf0 [nft_ct]

Signed-off-by: Pablo Neira Ayuso

netfilter: conntrack: reset tcp maxwin on re-register

2018-09-10T23:29:24+00:00

Doug Smythies says:
  Sometimes it is desirable to temporarily disable, or clear,
  the iptables rule set on a computer being controlled via a
  secure shell session (SSH). While unwise on an internet facing
  computer, I also do it often on non-internet accessible computers
  while testing. Recently, this has become problematic, with the
  SSH session being dropped upon re-load of the rule set.

The problem is that when all rules are deleted, conntrack hooks get
unregistered.

In case the rules are re-added later, its possible that tcp window
has moved far enough so that all packets are considered invalid (out of
window) until entry expires (which can take forever, default
established timeout is 5 days).

Fix this by clearing maxwin of existing tcp connections on register.

v2: don't touch entries on hook removal.
v3: remove obsolete expiry check.

Reported-by: Doug Smythies 
Fixes: 4d3a57f23dec59 ("netfilter: conntrack: do not enable connection tracking unless needed")
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso