linux-stable.git/net/bridge, branch v4.17.2

netfilter: ebtables: handle string from userspace with care

2018-05-17T11:48:48+00:00

strlcpy() can't be safely used on a user-space provided string,
as it can try to read beyond the buffer's end, if the latter is
not NULL terminated.

Leveraging the above, syzbot has been able to trigger the following
splat:

BUG: KASAN: stack-out-of-bounds in strlcpy include/linux/string.h:300
[inline]
BUG: KASAN: stack-out-of-bounds in compat_mtw_from_user
net/bridge/netfilter/ebtables.c:1957 [inline]
BUG: KASAN: stack-out-of-bounds in ebt_size_mwt
net/bridge/netfilter/ebtables.c:2059 [inline]
BUG: KASAN: stack-out-of-bounds in size_entry_mwt
net/bridge/netfilter/ebtables.c:2155 [inline]
BUG: KASAN: stack-out-of-bounds in compat_copy_entries+0x96c/0x14a0
net/bridge/netfilter/ebtables.c:2194
Write of size 33 at addr ffff8801b0abf888 by task syz-executor0/4504

CPU: 0 PID: 4504 Comm: syz-executor0 Not tainted 4.17.0-rc2+ #40
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
  __dump_stack lib/dump_stack.c:77 [inline]
  dump_stack+0x1b9/0x294 lib/dump_stack.c:113
  print_address_description+0x6c/0x20b mm/kasan/report.c:256
  kasan_report_error mm/kasan/report.c:354 [inline]
  kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
  check_memory_region_inline mm/kasan/kasan.c:260 [inline]
  check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267
  memcpy+0x37/0x50 mm/kasan/kasan.c:303
  strlcpy include/linux/string.h:300 [inline]
  compat_mtw_from_user net/bridge/netfilter/ebtables.c:1957 [inline]
  ebt_size_mwt net/bridge/netfilter/ebtables.c:2059 [inline]
  size_entry_mwt net/bridge/netfilter/ebtables.c:2155 [inline]
  compat_copy_entries+0x96c/0x14a0 net/bridge/netfilter/ebtables.c:2194
  compat_do_replace+0x483/0x900 net/bridge/netfilter/ebtables.c:2285
  compat_do_ebt_set_ctl+0x2ac/0x324 net/bridge/netfilter/ebtables.c:2367
  compat_nf_sockopt net/netfilter/nf_sockopt.c:144 [inline]
  compat_nf_setsockopt+0x9b/0x140 net/netfilter/nf_sockopt.c:156
  compat_ip_setsockopt+0xff/0x140 net/ipv4/ip_sockglue.c:1279
  inet_csk_compat_setsockopt+0x97/0x120 net/ipv4/inet_connection_sock.c:1041
  compat_tcp_setsockopt+0x49/0x80 net/ipv4/tcp.c:2901
  compat_sock_common_setsockopt+0xb4/0x150 net/core/sock.c:3050
  __compat_sys_setsockopt+0x1ab/0x7c0 net/compat.c:403
  __do_compat_sys_setsockopt net/compat.c:416 [inline]
  __se_compat_sys_setsockopt net/compat.c:413 [inline]
  __ia32_compat_sys_setsockopt+0xbd/0x150 net/compat.c:413
  do_syscall_32_irqs_on arch/x86/entry/common.c:323 [inline]
  do_fast_syscall_32+0x345/0xf9b arch/x86/entry/common.c:394
  entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7fb3cb9
RSP: 002b:00000000fff0c26c EFLAGS: 00000282 ORIG_RAX: 000000000000016e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000000000
RDX: 0000000000000080 RSI: 0000000020000300 RDI: 00000000000005f4
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

The buggy address belongs to the page:
page:ffffea0006c2afc0 count:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x2fffc0000000000()
raw: 02fffc0000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: 0000000000000000 ffffea0006c20101 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Fix the issue replacing the unsafe function with strscpy() and
taking care of possible errors.

Fixes: 81e675c227ec ("netfilter: ebtables: add CONFIG_COMPAT support")
Reported-and-tested-by: syzbot+4e42a04e0bc33cb6c087@syzkaller.appspotmail.com
Signed-off-by: Paolo Abeni 
Signed-off-by: Pablo Neira Ayuso

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

2018-05-14T00:28:47+00:00

Pablo Neira Ayuso says:

====================
Netfilter/IPVS fixes for net

The following patchset contains Netfilter/IPVS fixes for your net tree,
they are:

1) Fix handling of simultaneous open TCP connection in conntrack,
   from Jozsef Kadlecsik.

2) Insufficient sanitify check of xtables extension names, from
   Florian Westphal.

3) Skip unnecessary synchronize_rcu() call when transaction log
   is already empty, from Florian Westphal.

4) Incorrect destination mac validation in ebt_stp, from Stephen
   Hemminger.

5) xtables module reference counter leak in nft_compat, from
   Florian Westphal.

6) Incorrect connection reference counting logic in IPVS
   one-packet scheduler, from Julian Anastasov.

7) Wrong stats for 32-bits CPU in IPVS, also from Julian.

8) Calm down sparse error in netfilter core, also from Florian.

9) Use nla_strlcpy to fix compilation warning in nfnetlink_acct
   and nfnetlink_cthelper, again from Florian.

10) Missing module alias in icmp and icmp6 xtables extensions,
    from Florian Westphal.

11) Base chain statistics in nf_tables may be unset/null, from Florian.

12) Fix handling of large matchinfo size in nft_compat, this includes
    one preparation for before this fix. From Florian.

13) Fix bogus EBUSY error when deleting chains due to incorrect reference
    counting from the preparation phase of the two-phase commit protocol.
====================

Signed-off-by: David S. Miller

netfilter: bridge: stp fix reference to uninitialized data

2018-05-08T12:08:12+00:00

The destination mac (destmac) is only valid if EBT_DESTMAC flag
is set. Fix by changing the order of the comparison to look for
the flag first.

Reported-by: syzbot+5c06e318fc558cc27823@syzkaller.appspotmail.com
Signed-off-by: Stephen Hemminger 
Signed-off-by: Pablo Neira Ayuso

bridge: check iface upper dev when setting master via ioctl

2018-04-30T01:08:02+00:00

When we set a bond slave's master to bridge via ioctl, we only check
the IFF_BRIDGE_PORT flag. Although we will find the slave's real master
at netdev_master_upper_dev_link() later, it already does some settings
and allocates some resources. It would be better to return as early
as possible.

v1 -> v2:
use netdev_master_upper_dev_get() instead of netdev_has_any_upper_dev()
to check if we have a master, because not all upper devs are masters,
e.g. vlan device.

Reported-by: syzbot+de73361ee4971b6e6f75@syzkaller.appspotmail.com
Signed-off-by: Hangbin Liu 
Acked-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

netfilter: ebtables: don't attempt to allocate 0-sized compat array

2018-04-09T15:05:48+00:00

Dmitry reports 32bit ebtables on 64bit kernel got broken by
a recent change that returns -EINVAL when ruleset has no entries.

ebtables however only counts user-defined chains, so for the
initial table nentries will be 0.

Don't try to allocate the compat array in this case, as no user
defined rules exist no rule will need 64bit translation.

Reported-by: Dmitry Vyukov 
Fixes: 7d7d7e02111e9 ("netfilter: compat: reject huge allocation requests")
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso

net: bridge: disable bridge MTU auto tuning if it was set manually

2018-04-01T02:19:00+00:00

As Roopa noted today the biggest source of problems when configuring
bridge and ports is that the bridge MTU keeps changing automatically on
port events (add/del/changemtu). That leads to inconsistent behaviour
and network config software needs to chase the MTU and fix it on each
such event. Let's improve on that situation and allow for the user to
set any MTU within ETH_MIN/MAX limits, but once manually configured it
is the user's responsibility to keep it correct afterwards.

In case the MTU isn't manually set - the behaviour reverts to the
previous and the bridge follows the minimum MTU.

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

net: bridge: set min MTU on port events and allow user to set max

2018-04-01T02:19:00+00:00

Recently the bridge was changed to automatically set maximum MTU on port
events (add/del/changemtu) when vlan filtering is enabled, but that
actually changes behaviour in a way which breaks some setups and can lead
to packet drops. In order to still allow that maximum to be set while being
compatible, we add the ability for the user to tune the bridge MTU up to
the maximum when vlan filtering is enabled, but that has to be done
explicitly and all port events (add/del/changemtu) lead to resetting that
MTU to the minimum as before.

Suggested-by: Roopa Prabhu 
Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

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

2018-03-30T15:41:18+00:00

Pablo Neira Ayuso says:

====================
Netfilter/IPVS updates for net-next

The following patchset contains Netfilter/IPVS updates for your net-next
tree. This batch comes with more input sanitization for xtables to
address bug reports from fuzzers, preparation works to the flowtable
infrastructure and assorted updates. In no particular order, they are:

1) Make sure userspace provides a valid standard target verdict, from
   Florian Westphal.

2) Sanitize error target size, also from Florian.

3) Validate that last rule in basechain matches underflow/policy since
   userspace assumes this when decoding the ruleset blob that comes
   from the kernel, from Florian.

4) Consolidate hook entry checks through xt_check_table_hooks(),
   patch from Florian.

5) Cap ruleset allocations at 512 mbytes, 134217728 rules and reject
   very large compat offset arrays, so we have a reasonable upper limit
   and fuzzers don't exercise the oom-killer. Patches from Florian.

6) Several WARN_ON checks on xtables mutex helper, from Florian.

7) xt_rateest now has a hashtable per net, from Cong Wang.

8) Consolidate counter allocation in xt_counters_alloc(), from Florian.

9) Earlier xt_table_unlock() call in {ip,ip6,arp,eb}tables, patch
   from Xin Long.

10) Set FLOW_OFFLOAD_DIR_* to IP_CT_DIR_* definitions, patch from
    Felix Fietkau.

11) Consolidate code through flow_offload_fill_dir(), also from Felix.

12) Inline ip6_dst_mtu_forward() just like ip_dst_mtu_maybe_forward()
    to remove a dependency with flowtable and ipv6.ko, from Felix.

13) Cache mtu size in flow_offload_tuple object, this is safe for
    forwarding as f87c10a8aa1e describes, from Felix.

14) Rename nf_flow_table.c to nf_flow_table_core.o, to simplify too
    modular infrastructure, from Felix.

15) Add rt0, rt2 and rt4 IPv6 routing extension support, patch from
    Ahmed Abdelsalam.

16) Remove unused parameter in nf_conncount_count(), from Yi-Hung Wei.

17) Support for counting only to nf_conncount infrastructure, patch
    from Yi-Hung Wei.

18) Add strict NFT_CT_{SRC_IP,DST_IP,SRC_IP6,DST_IP6} key datatypes
    to nft_ct.

19) Use boolean as return value from ipt_ah and from IPVS too, patch
    from Gustavo A. R. Silva.

20) Remove useless parameters in nfnl_acct_overquota() and
    nf_conntrack_broadcast_help(), from Taehee Yoo.

21) Use ipv6_addr_is_multicast() from xt_cluster, also from Taehee Yoo.

22) Statify nf_tables_obj_lookup_byhandle, patch from Fengguang Wu.

23) Fix typo in xt_limit, from Geert Uytterhoeven.

24) Do no use VLAs in Netfilter code, again from Gustavo.

25) Use ADD_COUNTER from ebtables, from Taehee Yoo.

26) Bitshift support for CONNMARK and MARK targets, from Jack Ma.

27) Use pr_*() and add pr_fmt(), from Arushi Singhal.

28) Add synproxy support to ctnetlink.

29) ICMP type and IGMP matching support for ebtables, patches from
    Matthias Schiffer.

30) Support for the revision infrastructure to ebtables, from
    Bernie Harris.

31) String match support for ebtables, also from Bernie.

32) Documentation for the new flowtable infrastructure.

33) Use generic comparison functions in ebt_stp, from Joe Perches.

34) Demodularize filter chains in nftables.

35) Register conntrack hooks in case nftables NAT chain is added.

36) Merge assignments with return in a couple of spots in the
    Netfilter codebase, also from Arushi.

37) Document that xtables percpu counters are stored in the same
    memory area, from Ben Hutchings.

38) Revert mark_source_chains() sanity checks that break existing
    rulesets, from Florian Westphal.

39) Use is_zero_ether_addr() in the ipset codebase, from Joe Perches.
====================

Signed-off-by: David S. Miller

netfilter: nf_tables: build-in filter chain type

2018-03-30T09:29:19+00:00

One module per supported filter chain family type takes too much memory
for very little code - too much modularization - place all chain filter
definitions in one single file.

Signed-off-by: Pablo Neira Ayuso

netfilter: nf_tables: nft_register_chain_type() returns void

2018-03-30T09:29:18+00:00

Use WARN_ON() instead since it should not happen that neither family
goes over NFPROTO_NUMPROTO nor there is already a chain of this type
already registered.

Signed-off-by: Pablo Neira Ayuso