commit 47c3e7783be4e142b861d34b5c2e223330b05d8a upstream.

PPPOL2TP_MSG_* and L2TP_MSG_* are duplicates, and are being used
interchangeably in the kernel, so let's standardize on L2TP_MSG_*
internally, and keep PPPOL2TP_MSG_* defined in UAPI for compatibility.

Signed-off-by: Asbjoern Sloth Toennesen <asbjorn@asbjorn.st>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Giuliano Procida <gprocida@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 5f3e2bf008c2221478101ee72f5cb4654b9fc363 upstream.

Some TCP peers announce a very small MSS option in their SYN and/or
SYN/ACK messages.

This forces the stack to send packets with a very high network/cpu
overhead.

Linux has enforced a minimal value of 48. Since this value includes
the size of TCP options, and that the options can consume up to 40
bytes, this means that each segment can include only 8 bytes of payload.

In some cases, it can be useful to increase the minimal value
to a saner value.

We still let the default to 48 (TCP_MIN_SND_MSS), for compatibility
reasons.

Note that TCP_MAXSEG socket option enforces a minimal value
of (TCP_MIN_MSS). David Miller increased this minimal value
in commit c39508d6f118 ("tcp: Make TCP_MAXSEG minimum more correct.")
from 64 to 88.

We might in the future merge TCP_MIN_SND_MSS and TCP_MIN_MSS.

CVE-2019-11479 -- tcp mss hardcoded to 48

Signed-off-by: Eric Dumazet <edumazet@google.com>
Suggested-by: Jonathan Looney <jtl@netflix.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Tyler Hicks <tyhicks@canonical.com>
Cc: Bruce Curtis <brucec@netflix.com>
Cc: Jonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit 19fad20d15a6494f47f85d869f00b11343ee5c78 ]

There is a UBSAN report as below:
UBSAN: Undefined behaviour in net/ipv4/tcp_input.c:2877:56
signed integer overflow:
2147483647 * 1000 cannot be represented in type 'int'
CPU: 3 PID: 0 Comm: swapper/3 Not tainted 5.1.0-rc4-00058-g582549e #1
Call Trace:
 <IRQ>
 dump_stack+0x8c/0xba
 ubsan_epilogue+0x11/0x60
 handle_overflow+0x12d/0x170
 ? ttwu_do_wakeup+0x21/0x320
 __ubsan_handle_mul_overflow+0x12/0x20
 tcp_ack_update_rtt+0x76c/0x780
 tcp_clean_rtx_queue+0x499/0x14d0
 tcp_ack+0x69e/0x1240
 ? __wake_up_sync_key+0x2c/0x50
 ? update_group_capacity+0x50/0x680
 tcp_rcv_established+0x4e2/0xe10
 tcp_v4_do_rcv+0x22b/0x420
 tcp_v4_rcv+0xfe8/0x1190
 ip_protocol_deliver_rcu+0x36/0x180
 ip_local_deliver+0x15b/0x1a0
 ip_rcv+0xac/0xd0
 __netif_receive_skb_one_core+0x7f/0xb0
 __netif_receive_skb+0x33/0xc0
 netif_receive_skb_internal+0x84/0x1c0
 napi_gro_receive+0x2a0/0x300
 receive_buf+0x3d4/0x2350
 ? detach_buf_split+0x159/0x390
 virtnet_poll+0x198/0x840
 ? reweight_entity+0x243/0x4b0
 net_rx_action+0x25c/0x770
 __do_softirq+0x19b/0x66d
 irq_exit+0x1eb/0x230
 do_IRQ+0x7a/0x150
 common_interrupt+0xf/0xf
 </IRQ>

It can be reproduced by:
  echo 2147483647 > /proc/sys/net/ipv4/tcp_min_rtt_wlen

Fixes: f672258391b42 ("tcp: track min RTT using windowed min-filter")
Signed-off-by: ZhangXiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Some users are willing to provision huge amounts of memory to be able
to perform reassembly reasonnably well under pressure.

Current memory tracking is using one atomic_t and integers.

Switch to atomic_long_t so that 64bit arches can use more than 2GB,
without any cost for 32bit arches.

Note that this patch avoids an overflow error, if high_thresh was set
to ~2GB, since this test in inet_frag_alloc() was never true :

if (... || frag_mem_limit(nf) > nf->high_thresh)

Tested:

$ echo 16000000000 >/proc/sys/net/ipv4/ipfrag_high_thresh

<frag DDOS>

$ grep FRAG /proc/net/sockstat
FRAG: inuse 14705885 memory 16000002880

$ nstat -n ; sleep 1 ; nstat | grep Reas
IpReasmReqds                    3317150            0.0
IpReasmFails                    3317112            0.0

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 3e67f106f619dcfaf6f4e2039599bdb69848c714)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Some applications still rely on IP fragmentation, and to be fair linux
reassembly unit is not working under any serious load.

It uses static hash tables of 1024 buckets, and up to 128 items per bucket (!!!)

A work queue is supposed to garbage collect items when host is under memory
pressure, and doing a hash rebuild, changing seed used in hash computations.

This work queue blocks softirqs for up to 25 ms when doing a hash rebuild,
occurring every 5 seconds if host is under fire.

Then there is the problem of sharing this hash table for all netns.

It is time to switch to rhashtables, and allocate one of them per netns
to speedup netns dismantle, since this is a critical metric these days.

Lookup is now using RCU. A followup patch will even remove
the refcount hold/release left from prior implementation and save
a couple of atomic operations.

Before this patch, 16 cpus (16 RX queue NIC) could not handle more
than 1 Mpps frags DDOS.

After the patch, I reach 9 Mpps without any tuning, and can use up to 2GB
of storage for the fragments (exact number depends on frags being evicted
after timeout)

$ grep FRAG /proc/net/sockstat
FRAG: inuse 1966916 memory 2140004608

A followup patch will change the limits for 64bit arches.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Florian Westphal <fw@strlen.de>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Alexander Aring <alex.aring@gmail.com>
Cc: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 648700f76b03b7e8149d13cc2bdb3355035258a9)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit 75d4e704fa8d2cf33ff295e5b441317603d7f9fd ]

Per discussion with David at netconf 2018, let's clarify
DaveM's position of handling stable backports in netdev-FAQ.

This is important for people relying on upstream -stable
releases.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Since kernel 4.7 this defaults to off.

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

Add Qualcomm QCA tagging introduced in cafdc45c9 to the
list of supported protocols.

Signed-off-by: Fabian Mewes <architekt@coding4coffee.org>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull networking fixes from David Miller:
 "Lots of fixes, mostly drivers as is usually the case.

   1) Don't treat zero DMA address as invalid in vmxnet3, from Alexey
      Khoroshilov.

   2) Fix element timeouts in netfilter's nft_dynset, from Anders K.
      Pedersen.

   3) Don't put aead_req crypto struct on the stack in mac80211, from
      Ard Biesheuvel.

   4) Several uninitialized variable warning fixes from Arnd Bergmann.

   5) Fix memory leak in cxgb4, from Colin Ian King.

   6) Fix bpf handling of VLAN header push/pop, from Daniel Borkmann.

   7) Several VRF semantic fixes from David Ahern.

   8) Set skb->protocol properly in ip6_tnl_xmit(), from Eli Cooper.

   9) Socket needs to be locked in udp_disconnect(), from Eric Dumazet.

  10) Div-by-zero on 32-bit fix in mlx4 driver, from Eugenia Emantayev.

  11) Fix stale link state during failover in NCSCI driver, from Gavin
      Shan.

  12) Fix netdev lower adjacency list traversal, from Ido Schimmel.

  13) Propvide proper handle when emitting notifications of filter
      deletes, from Jamal Hadi Salim.

  14) Memory leaks and big-endian issues in rtl8xxxu, from Jes Sorensen.

  15) Fix DESYNC_FACTOR handling in ipv6, from Jiri Bohac.

  16) Several routing offload fixes in mlxsw driver, from Jiri Pirko.

  17) Fix broadcast sync problem in TIPC, from Jon Paul Maloy.

  18) Validate chunk len before using it in SCTP, from Marcelo Ricardo
      Leitner.

  19) Revert a netns locking change that causes regressions, from Paul
      Moore.

  20) Add recursion limit to GRO handling, from Sabrina Dubroca.

  21) GFP_KERNEL in irq context fix in ibmvnic, from Thomas Falcon.

  22) Avoid accessing stale vxlan/geneve socket in data path, from
      Pravin Shelar"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (189 commits)
  geneve: avoid using stale geneve socket.
  vxlan: avoid using stale vxlan socket.
  qede: Fix out-of-bound fastpath memory access
  net: phy: dp83848: add dp83822 PHY support
  enic: fix rq disable
  tipc: fix broadcast link synchronization problem
  ibmvnic: Fix missing brackets in init_sub_crq_irqs
  ibmvnic: Fix releasing of sub-CRQ IRQs in interrupt context
  Revert "ibmvnic: Fix releasing of sub-CRQ IRQs in interrupt context"
  arch/powerpc: Update parameters for csum_tcpudp_magic & csum_tcpudp_nofold
  net/mlx4_en: Save slave ethtool stats command
  net/mlx4_en: Fix potential deadlock in port statistics flow
  net/mlx4: Fix firmware command timeout during interrupt test
  net/mlx4_core: Do not access comm channel if it has not yet been initialized
  net/mlx4_en: Fix panic during reboot
  net/mlx4_en: Process all completions in RX rings after port goes up
  net/mlx4_en: Resolve dividing by zero in 32-bit system
  net/mlx4_core: Change the default value of enable_qos
  net/mlx4_core: Avoid setting ports to auto when only one port type is supported
  net/mlx4_core: Fix the resource-type enum in res tracker to conform to FW spec
  ...

Pablo Neira Ayuso says:

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

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

1) Fix compilation warning in xt_hashlimit on m68k 32-bits, from
   Geert Uytterhoeven.

2) Fix wrong timeout in set elements added from packet path via
   nft_dynset, from Anders K. Pedersen.

3) Remove obsolete nf_conntrack_events_retry_timeout sysctl
   documentation, from Nicolas Dichtel.

4) Ensure proper initialization of log flags via xt_LOG, from
   Liping Zhang.

5) Missing alias to autoload ipcomp, also from Liping Zhang.

6) Missing NFTA_HASH_OFFSET attribute validation, again from Liping.

7) Wrong integer type in the new nft_parse_u32_check() function,
   from Dan Carpenter.

8) Another wrong integer type declaration in nft_exthdr_init, also
   from Dan Carpenter.

9) Fix insufficient mode validation in nft_range.

10) Fix compilation warning in nft_range due to possible uninitialized
    value, from Arnd Bergmann.

11) Zero nf_hook_ops allocated via xt_hook_alloc() in x_tables to
    calm down kmemcheck, from Florian Westphal.

12) Schedule gc_worker() to run again if GC_MAX_EVICTS quota is reached,
    from Nicolas Dichtel.

13) Fix nf_queue() after conversion to single-linked hook list, related
    to incorrect bypass flag handling and incorrect hook point of
    reinjection.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>