linux-stable.git/include/net, branch v5.1.7

inet: switch IP ID generator to siphash

2019-06-04T05:59:40+00:00

[ Upstream commit df453700e8d81b1bdafdf684365ee2b9431fb702 ]

According to Amit Klein and Benny Pinkas, IP ID generation is too weak
and might be used by attackers.

Even with recent net_hash_mix() fix (netns: provide pure entropy for net_hash_mix())
having 64bit key and Jenkins hash is risky.

It is time to switch to siphash and its 128bit keys.

Signed-off-by: Eric Dumazet 
Reported-by: Amit Klein 
Reported-by: Benny Pinkas 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

Bluetooth: Ignore CC events not matching the last HCI command

2019-05-31T13:43:16+00:00

[ Upstream commit f80c5dad7b6467b884c445ffea45985793b4b2d0 ]

This commit makes the kernel not send the next queued HCI command until
a command complete arrives for the last HCI command sent to the
controller. This change avoids a problem with some buggy controllers
(seen on two SKUs of QCA9377) that send an extra command complete event
for the previous command after the kernel had already sent a new HCI
command to the controller.

The problem was reproduced when starting an active scanning procedure,
where an extra command complete event arrives for the LE_SET_RANDOM_ADDR
command. When this happends the kernel ends up not processing the
command complete for the following commmand, LE_SET_SCAN_PARAM, and
ultimately behaving as if a passive scanning procedure was being
performed, when in fact controller is performing an active scanning
procedure. This makes it impossible to discover BLE devices as no device
found events are sent to userspace.

This problem is reproducible on 100% of the attempts on the affected
controllers. The extra command complete event can be seen at timestamp
27.420131 on the btmon logs bellow.

Bluetooth monitor ver 5.50
= Note: Linux version 5.0.0+ (x86_64)                                  0.352340
= Note: Bluetooth subsystem version 2.22                               0.352343
= New Index: 80:C5:F2:8F:87:84 (Primary,USB,hci0)               [hci0] 0.352344
= Open Index: 80:C5:F2:8F:87:84                                 [hci0] 0.352345
= Index Info: 80:C5:F2:8F:87:84 (Qualcomm)                      [hci0] 0.352346
@ MGMT Open: bluetoothd (privileged) version 1.14             {0x0001} 0.352347
@ MGMT Open: btmon (privileged) version 1.14                  {0x0002} 0.352366
@ MGMT Open: btmgmt (privileged) version 1.14                {0x0003} 27.302164
@ MGMT Command: Start Discovery (0x0023) plen 1       {0x0003} [hci0] 27.302310
        Address type: 0x06
          LE Public
          LE Random
< HCI Command: LE Set Random Address (0x08|0x0005) plen 6   #1 [hci0] 27.302496
        Address: 15:60:F2:91:B2:24 (Non-Resolvable)
> HCI Event: Command Complete (0x0e) plen 4                 #2 [hci0] 27.419117
      LE Set Random Address (0x08|0x0005) ncmd 1
        Status: Success (0x00)
< HCI Command: LE Set Scan Parameters (0x08|0x000b) plen 7  #3 [hci0] 27.419244
        Type: Active (0x01)
        Interval: 11.250 msec (0x0012)
        Window: 11.250 msec (0x0012)
        Own address type: Random (0x01)
        Filter policy: Accept all advertisement (0x00)
> HCI Event: Command Complete (0x0e) plen 4                 #4 [hci0] 27.420131
      LE Set Random Address (0x08|0x0005) ncmd 1
        Status: Success (0x00)
< HCI Command: LE Set Scan Enable (0x08|0x000c) plen 2      #5 [hci0] 27.420259
        Scanning: Enabled (0x01)
        Filter duplicates: Enabled (0x01)
> HCI Event: Command Complete (0x0e) plen 4                 #6 [hci0] 27.420969
      LE Set Scan Parameters (0x08|0x000b) ncmd 1
        Status: Success (0x00)
> HCI Event: Command Complete (0x0e) plen 4                 #7 [hci0] 27.421983
      LE Set Scan Enable (0x08|0x000c) ncmd 1
        Status: Success (0x00)
@ MGMT Event: Command Complete (0x0001) plen 4        {0x0003} [hci0] 27.422059
      Start Discovery (0x0023) plen 1
        Status: Success (0x00)
        Address type: 0x06
          LE Public
          LE Random
@ MGMT Event: Discovering (0x0013) plen 2             {0x0003} [hci0] 27.422067
        Address type: 0x06
          LE Public
          LE Random
        Discovery: Enabled (0x01)
@ MGMT Event: Discovering (0x0013) plen 2             {0x0002} [hci0] 27.422067
        Address type: 0x06
          LE Public
          LE Random
        Discovery: Enabled (0x01)
@ MGMT Event: Discovering (0x0013) plen 2             {0x0001} [hci0] 27.422067
        Address type: 0x06
          LE Public
          LE Random
        Discovery: Enabled (0x01)

Signed-off-by: João Paulo Rechi Vita 
Signed-off-by: Marcel Holtmann 
Signed-off-by: Sasha Levin

flow_offload: support CVLAN match

2019-05-25T16:16:15+00:00

[ Upstream commit bae9ed69029c7d499c57485593b2faae475fd704 ]

Plumb it through from the flow_dissector.

Signed-off-by: Edward Cree 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: prevent possible fib6 leaks

2019-05-25T16:16:11+00:00

[ Upstream commit 61fb0d01680771f72cc9d39783fb2c122aaad51e ]

At ipv6 route dismantle, fib6_drop_pcpu_from() is responsible
for finding all percpu routes and set their ->from pointer
to NULL, so that fib6_ref can reach its expected value (1).

The problem right now is that other cpus can still catch the
route being deleted, since there is no rcu grace period
between the route deletion and call to fib6_drop_pcpu_from()

This can leak the fib6 and associated resources, since no
notifier will take care of removing the last reference(s).

I decided to add another boolean (fib6_destroying) instead
of reusing/renaming exception_bucket_flushed to ease stable backports,
and properly document the memory barriers used to implement this fix.

This patch has been co-developped with Wei Wang.

Fixes: 93531c674315 ("net/ipv6: separate handling of FIB entries from dst based routes")
Signed-off-by: Eric Dumazet 
Reported-by: syzbot 
Cc: Wei Wang 
Cc: David Ahern 
Cc: Martin Lau 
Acked-by: Wei Wang 
Acked-by: Martin KaFai Lau 
Reviewed-by: David Ahern 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

Bluetooth: Align minimum encryption key size for LE and BR/EDR connections

2019-05-11T05:49:55+00:00

commit d5bb334a8e171b262e48f378bd2096c0ea458265 upstream.

The minimum encryption key size for LE connections is 56 bits and to
align LE with BR/EDR, enforce 56 bits of minimum encryption key size for
BR/EDR connections as well.

Signed-off-by: Marcel Holtmann 
Signed-off-by: Johan Hedberg 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

sctp: avoid running the sctp state machine recursively

2019-05-01T13:18:57+00:00

Ying triggered a call trace when doing an asconf testing:

  BUG: scheduling while atomic: swapper/12/0/0x10000100
  Call Trace:
     [] dump_stack+0x19/0x1b
   [] __schedule_bug+0x64/0x72
   [] __schedule+0x9ba/0xa00
   [] __cond_resched+0x26/0x30
   [] _cond_resched+0x3a/0x50
   [] kmem_cache_alloc_node+0x38/0x200
   [] __alloc_skb+0x5d/0x2d0
   [] sctp_packet_transmit+0x610/0xa20 [sctp]
   [] sctp_outq_flush+0x2ce/0xc00 [sctp]
   [] sctp_outq_uncork+0x1c/0x20 [sctp]
   [] sctp_cmd_interpreter.isra.22+0xc8/0x1460 [sctp]
   [] sctp_do_sm+0xe1/0x350 [sctp]
   [] sctp_primitive_ASCONF+0x3d/0x50 [sctp]
   [] sctp_cmd_interpreter.isra.22+0x114/0x1460 [sctp]
   [] sctp_do_sm+0xe1/0x350 [sctp]
   [] sctp_assoc_bh_rcv+0xf4/0x1b0 [sctp]
   [] sctp_inq_push+0x51/0x70 [sctp]
   [] sctp_rcv+0xa8b/0xbd0 [sctp]

As it shows, the first sctp_do_sm() running under atomic context (NET_RX
softirq) invoked sctp_primitive_ASCONF() that uses GFP_KERNEL flag later,
and this flag is supposed to be used in non-atomic context only. Besides,
sctp_do_sm() was called recursively, which is not expected.

Vlad tried to fix this recursive call in Commit c0786693404c ("sctp: Fix
oops when sending queued ASCONF chunks") by introducing a new command
SCTP_CMD_SEND_NEXT_ASCONF. But it didn't work as this command is still
used in the first sctp_do_sm() call, and sctp_primitive_ASCONF() will
be called in this command again.

To avoid calling sctp_do_sm() recursively, we send the next queued ASCONF
not by sctp_primitive_ASCONF(), but by sctp_sf_do_prm_asconf() in the 1st
sctp_do_sm() directly.

Reported-by: Ying Xu 
Signed-off-by: Xin Long 
Acked-by: Neil Horman 
Acked-by: Marcelo Ricardo Leitner 
Signed-off-by: David S. Miller

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec

2019-04-30T13:11:10+00:00

Steffen Klassert says:

====================
pull request (net): ipsec 2019-04-30

1) Fix an out-of-bound array accesses in __xfrm_policy_unlink.
   From YueHaibing.

2) Reset the secpath on failure in the ESP GRO handlers
   to avoid dereferencing an invalid pointer on error.
   From Myungho Jung.

3) Add and revert a patch that tried to add rcu annotations
   to netns_xfrm. From Su Yanjun.

4) Wait for rcu callbacks before freeing xfrm6_tunnel_spi_kmem.
   From Su Yanjun.

5) Fix forgotten vti4 ipip tunnel deregistration.
   From Jeremy Sowden:

6) Remove some duplicated log messages in vti4.
   From Jeremy Sowden.

7) Don't use IPSEC_PROTO_ANY when flushing states because
   this will flush only IPsec portocol speciffic states.
   IPPROTO_ROUTING states may remain in the lists when
   doing net exit. Fix this by replacing IPSEC_PROTO_ANY
   with zero. From Cong Wang.

8) Add length check for UDP encapsulation to fix "Oversized IP packet"
   warnings on receive side. From Sabrina Dubroca.

9) Fix xfrm interface lookup when the interface is associated to
   a vrf layer 3 master device. From Martin Willi.

10) Reload header pointers after pskb_may_pull() in _decode_session4(),
    otherwise we may read from uninitialized memory.

11) Update the documentation about xfrm[46]_gc_thresh, it
    is not used anymore after the flowcache removal.
    From Nicolas Dichtel.
====================

Signed-off-by: David S. Miller

netfilter: ctnetlink: don't use conntrack/expect object addresses as id

2019-04-15T05:31:44+00:00

else, we leak the addresses to userspace via ctnetlink events
and dumps.

Compute an ID on demand based on the immutable parts of nf_conn struct.

Another advantage compared to using an address is that there is no
immediate re-use of the same ID in case the conntrack entry is freed and
reallocated again immediately.

Fixes: 3583240249ef ("[NETFILTER]: nf_conntrack_expect: kill unique ID")
Fixes: 7f85f914721f ("[NETFILTER]: nf_conntrack: kill unique ID")
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso

netfilter: conntrack: don't set related state for different outer address

2019-04-13T12:52:57+00:00

Luca Moro says:
 ------
The issue lies in the filtering of ICMP and ICMPv6 errors that include an
inner IP datagram.
For these packets, icmp_error_message() extract the ICMP error and inner
layer to search of a known state.
If a state is found the packet is tagged as related (IP_CT_RELATED).

The problem is that there is no correlation check between the inner and
outer layer of the packet.
So one can encapsulate an error with an inner layer matching a known state,
while its outer layer is directed to a filtered host.
In this case the whole packet will be tagged as related.
This has various implications from a rule bypass (if a rule to related
trafic is allow), to a known state oracle.

Unfortunately, we could not find a real statement in a RFC on how this case
should be filtered.
The closest we found is RFC5927 (Section 4.3) but it is not very clear.

A possible fix would be to check that the inner IP source is the same than
the outer destination.

We believed this kind of attack was not documented yet, so we started to
write a blog post about it.
You can find it attached to this mail (sorry for the extract quality).
It contains more technical details, PoC and discussion about the identified
behavior.
We discovered later that
https://www.gont.com.ar/papers/filtering-of-icmp-error-messages.pdf
described a similar attack concept in 2004 but without the stateful
filtering in mind.
 -----

This implements above suggested fix:
In icmp(v6) error handler, take outer destination address, then pass
that into the common function that does the "related" association.

After obtaining the nf_conn of the matching inner-headers connection,
check that the destination address of the opposite direction tuple
is the same as the outer address and only set RELATED if thats the case.

Reported-by: Luca Moro 
Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso

rxrpc: Make rxrpc_kernel_check_life() indicate if call completed

2019-04-12T23:57:23+00:00

Make rxrpc_kernel_check_life() pass back the life counter through the
argument list and return true if the call has not yet completed.

Suggested-by: Marc Dionne 
Signed-off-by: David Howells 
Signed-off-by: David S. Miller