linux-stable.git/net/netfilter, branch v5.4.23

netfilter: xt_hashlimit: limit the max size of hashtable

2020-02-28T16:22:27+00:00

commit 8d0015a7ab76b8b1e89a3e5f5710a6e5103f2dd5 upstream.

The user-specified hashtable size is unbound, this could
easily lead to an OOM or a hung task as we hold the global
mutex while allocating and initializing the new hashtable.

Add a max value to cap both cfg->size and cfg->max, as
suggested by Florian.

Reported-and-tested-by: syzbot+adf6c6c2be1c3a718121@syzkaller.appspotmail.com
Signed-off-by: Cong Wang 
Reviewed-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman

netfilter: nft_tunnel: add the missing ERSPAN_VERSION nla_policy

2020-02-24T07:36:37+00:00

[ Upstream commit 0705f95c332081036d85f26691e9d3cd7d901c31 ]

ERSPAN_VERSION is an attribute parsed in kernel side, nla_policy
type should be added for it, like other attributes.

Fixes: af308b94a2a4 ("netfilter: nf_tables: add tunnel support")
Signed-off-by: Xin Long 
Reviewed-by: Simon Horman 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: ipset: fix suspicious RCU usage in find_set_and_id

2020-02-11T12:35:07+00:00

commit 5038517119d50ed0240059b1d7fc2faa92371c08 upstream.

find_set_and_id() is called when the NFNL_SUBSYS_IPSET mutex is held.
However, in the error path there can be a follow-up recvmsg() without
the mutex held. Use the start() function of struct netlink_dump_control
instead of dump() to verify and report if the specified set does not
exist.

Thanks to Pablo Neira Ayuso for helping me to understand the subleties
of the netlink protocol.

Reported-by: syzbot+fc69d7cb21258ab4ae4d@syzkaller.appspotmail.com
Signed-off-by: Jozsef Kadlecsik 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman

netfilter: nf_tables_offload: fix check the chain offload flag

2020-02-05T21:22:52+00:00

[ Upstream commit c83de17dd6308fb74696923e5245de0e3c427206 ]

In the nft_indr_block_cb the chain should check the flag with
NFT_CHAIN_HW_OFFLOAD.

Fixes: 9a32669fecfb ("netfilter: nf_tables_offload: support indr block call")
Signed-off-by: wenxu 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: conntrack: sctp: use distinct states for new SCTP connections

2020-02-05T21:22:52+00:00

[ Upstream commit ab658b9fa7a2c467f79eac8b53ea308b8f98113d ]

The netlink notifications triggered by the INIT and INIT_ACK chunks
for a tracked SCTP association do not include protocol information
for the corresponding connection - SCTP state and verification tags
for the original and reply direction are missing. Since the connection
tracking implementation allows user space programs to receive
notifications about a connection and then create a new connection
based on the values received in a notification, it makes sense that
INIT and INIT_ACK notifications should contain the SCTP state
and verification tags available at the time when a notification
is sent. The missing verification tags cause a newly created
netfilter connection to fail to verify the tags of SCTP packets
when this connection has been created from the values previously
received in an INIT or INIT_ACK notification.

A PROTOINFO event is cached in sctp_packet() when the state
of a connection changes. The CLOSED and COOKIE_WAIT state will
be used for connections that have seen an INIT and INIT_ACK chunk,
respectively. The distinct states will cause a connection state
change in sctp_packet().

Signed-off-by: Jiri Wiesner 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin

netfilter: nf_tables: autoload modules from the abort path

2020-01-29T15:45:33+00:00

commit eb014de4fd418de1a277913cba244e47274fe392 upstream.

This patch introduces a list of pending module requests. This new module
list is composed of nft_module_request objects that contain the module
name and one status field that tells if the module has been already
loaded (the 'done' field).

In the first pass, from the preparation phase, the netlink command finds
that a module is missing on this list. Then, a module request is
allocated and added to this list and nft_request_module() returns
-EAGAIN. This triggers the abort path with the autoload parameter set on
from nfnetlink, request_module() is called and the module request enters
the 'done' state. Since the mutex is released when loading modules from
the abort phase, the module list is zapped so this is iteration occurs
over a local list. Therefore, the request_module() calls happen when
object lists are in consistent state (after fulling aborting the
transaction) and the commit list is empty.

On the second pass, the netlink command will find that it already tried
to load the module, so it does not request it again and
nft_request_module() returns 0. Then, there is a look up to find the
object that the command was missing. If the module was successfully
loaded, the command proceeds normally since it finds the missing object
in place, otherwise -ENOENT is reported to userspace.

This patch also updates nfnetlink to include the reason to enter the
abort phase, which is required for this new autoload module rationale.

Fixes: ec7470b834fe ("netfilter: nf_tables: store transaction list locally while requesting module")
Reported-by: syzbot+29125d208b3dae9a7019@syzkaller.appspotmail.com
Signed-off-by: Pablo Neira Ayuso
Signed-off-by: Greg Kroah-Hartman

netfilter: nf_tables: add __nft_chain_type_get()

2020-01-29T15:45:33+00:00

commit 826035498ec14b77b62a44f0cb6b94d45530db6f upstream.

This new helper function validates that unknown family and chain type
coming from userspace do not trigger an out-of-bound array access. Bail
out in case __nft_chain_type_get() returns NULL from
nft_chain_parse_hook().

Fixes: 9370761c56b6 ("netfilter: nf_tables: convert built-in tables/chains to chain types")
Reported-by: syzbot+156a04714799b1d480bc@syzkaller.appspotmail.com
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman

netfilter: ipset: use bitmap infrastructure completely

2020-01-29T15:45:33+00:00

commit 32c72165dbd0e246e69d16a3ad348a4851afd415 upstream.

The bitmap allocation did not use full unsigned long sizes
when calculating the required size and that was triggered by KASAN
as slab-out-of-bounds read in several places. The patch fixes all
of them.

Reported-by: syzbot+fabca5cbf5e54f3fe2de@syzkaller.appspotmail.com
Reported-by: syzbot+827ced406c9a1d9570ed@syzkaller.appspotmail.com
Reported-by: syzbot+190d63957b22ef673ea5@syzkaller.appspotmail.com
Reported-by: syzbot+dfccdb2bdb4a12ad425e@syzkaller.appspotmail.com
Reported-by: syzbot+df0d0f5895ef1f41a65b@syzkaller.appspotmail.com
Reported-by: syzbot+b08bd19bb37513357fd4@syzkaller.appspotmail.com
Reported-by: syzbot+53cdd0ec0bbabd53370a@syzkaller.appspotmail.com
Signed-off-by: Jozsef Kadlecsik 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman

netfilter: nft_osf: add missing check for DREG attribute

2020-01-29T15:45:29+00:00

commit 7eaecf7963c1c8f62d62c6a8e7c439b0e7f2d365 upstream.

syzbot reports just another NULL deref crash because of missing test
for presence of the attribute.

Reported-by: syzbot+cf23983d697c26c34f60@syzkaller.appspotmail.com
Fixes:  b96af92d6eaf9fadd ("netfilter: nf_tables: implement Passive OS fingerprint module in nft_osf")
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman

netfilter: nf_tables: fix flowtable list del corruption

2020-01-23T07:22:48+00:00

commit 335178d5429c4cee61b58f4ac80688f556630818 upstream.

syzbot reported following crash:

  list_del corruption, ffff88808c9bb000->prev is LIST_POISON2 (dead000000000122)
  [..]
  Call Trace:
   __list_del_entry include/linux/list.h:131 [inline]
   list_del_rcu include/linux/rculist.h:148 [inline]
   nf_tables_commit+0x1068/0x3b30 net/netfilter/nf_tables_api.c:7183
   [..]

The commit transaction list has:

NFT_MSG_NEWTABLE
NFT_MSG_NEWFLOWTABLE
NFT_MSG_DELFLOWTABLE
NFT_MSG_DELTABLE

A missing generation check during DELTABLE processing causes it to queue
the DELFLOWTABLE operation a second time, so we corrupt the list here:

  case NFT_MSG_DELFLOWTABLE:
     list_del_rcu(&nft_trans_flowtable(trans)->list);
     nf_tables_flowtable_notify(&trans->ctx,

because we have two different DELFLOWTABLE transactions for the same
flowtable.  We then call list_del_rcu() twice for the same flowtable->list.

The object handling seems to suffer from the same bug so add a generation
check too and only queue delete transactions for flowtables/objects that
are still active in the next generation.

Reported-by: syzbot+37a6804945a3a13b1572@syzkaller.appspotmail.com
Fixes: 3b49e2e94e6eb ("netfilter: nf_tables: add flow table netlink frontend")
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Greg Kroah-Hartman