It has been reported that update_suffix can be expensive when it is called
on a large node in which most of the suffix lengths are the same.  The time
required to add 200K entries had increased from around 3 seconds to almost
49 seconds.

In order to address this we need to move the code for updating the suffix
out of resize and instead just have it handled in the cases where we are
pushing a node that increases the suffix length, or will decrease the
suffix length.

Fixes: 5405afd1 ("fib_trie: Add tracking value for suffix length")
Reported-by: NRobert Shearman <rshearma@brocade.com>
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Reviewed-by: NRobert Shearman <rshearma@brocade.com>
Tested-by: NRobert Shearman <rshearma@brocade.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It wasn't necessary to pass a leaf in when doing the suffix updates so just
drop it.  Instead just pass the suffix and work with that.

Since we dropped the leaf there is no need to include that in the name so
the names are updated to node_push_suffix and node_pull_suffix.

Finally I noticed that the logic for pulling the suffix length back
actually had some issues.  Specifically it would stop prematurely if there
was a longer suffix, but it was not as long as the original suffix.  I
updated the code to address that in node_pull_suffix.

Fixes: 5405afd1 ("fib_trie: Add tracking value for suffix length")
Suggested-by: NRobert Shearman <rshearma@brocade.com>
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Reviewed-by: NRobert Shearman <rshearma@brocade.com>
Tested-by: NRobert Shearman <rshearma@brocade.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When xfrm is applied to TSO/GSO packets, it follows this path:

    xfrm_output() -> xfrm_output_gso() -> skb_gso_segment()

where skb_gso_segment() relies on skb->protocol to function properly.

This patch sets skb->protocol to ETH_P_IP before dst_output() is called,
fixing a bug where GSO packets sent through a sit tunnel are dropped
when xfrm is involved.

Cc: stable@vger.kernel.org
Signed-off-by: NEli Cooper <elicooper@gmx.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since 09d96860 ("netfilter: x_tables: do compat validation via
translate_table"), it used compatr structure to assign newinfo
structure.  In translate_compat_table of ip_tables.c and ip6_tables.c,
it used compatr->hook_entry to replace info->hook_entry and
compatr->underflow to replace info->underflow, but not do the same
replacement in arp_tables.c.

It caused invoking 32-bit "arptbale -P INPUT ACCEPT" failed in 64bit
kernel.
--------------------------------------
root@qemux86-64:~# arptables -P INPUT ACCEPT
root@qemux86-64:~# arptables -P INPUT ACCEPT
ERROR: Policy for `INPUT' offset 448 != underflow 0
arptables: Incompatible with this kernel
--------------------------------------

Fixes: 09d96860 ("netfilter: x_tables: do compat validation via translate_table")
Signed-off-by: NHongxu Jia <hongxu.jia@windriver.com>
Acked-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

When handling inbound packets, the two halves of the sequence number
stored on the skb are already in network order.

Fixes: 7021b2e1 ("esp4: Switch to new AEAD interface")
Signed-off-by: NTobias Brunner <tobias@strongswan.org>
Acked-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

As it may get stale and lead to use after free.
Acked-by: NEric Dumazet <eric.dumazet@gmail.com>
Cc: Alexander Duyck <aduyck@mirantis.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Fixes: cbc53e08 ("GSO: Add GSO type for fixed IPv4 ID")
Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NJulian Wollrath <jwollrath@web.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In commits 93821778 ("udp: Fix rcv socket locking") and
f7ad74fe ("net/ipv6/udp: UDP encapsulation: break backlog_rcv into
__udpv6_queue_rcv_skb") UDP backlog handlers were renamed, but UDPlite
was forgotten.

This leads to crashes if UDPlite header is pulled twice, which happens
starting from commit e6afc8ac ("udp: remove headers from UDP packets
before queueing")

Bug found by syzkaller team, thanks a lot guys !

Note that backlog use in UDP/UDPlite is scheduled to be removed starting
from linux-4.10, so this patch is only needed up to linux-4.9

Fixes: 93821778 ("udp: Fix rcv socket locking")
Fixes: f7ad74fe ("net/ipv6/udp: UDP encapsulation: break backlog_rcv into __udpv6_queue_rcv_skb")
Fixes: e6afc8ac ("udp: remove headers from UDP packets before queueing")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reported-by: NAndrey Konovalov <andreyknvl@google.com>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ip_route_me_harder is not considering the L3 domain and sending lookups
to the wrong table. For example consider the following output rule:

iptables -I OUTPUT -p tcp --dport 12345 -j REJECT --reject-with tcp-reset

using perf to analyze lookups via the fib_table_lookup tracepoint shows:

vrf-test  1187 [001] 46887.295927: fib:fib_table_lookup: table 255 oif 0 iif 0 src 0.0.0.0 dst 10.100.1.254 tos 0 scope 0 flags 0
        ffffffff8143922c perf_trace_fib_table_lookup ([kernel.kallsyms])
        ffffffff81493aac fib_table_lookup ([kernel.kallsyms])
        ffffffff8148dda3 __inet_dev_addr_type ([kernel.kallsyms])
        ffffffff8148ddf6 inet_addr_type ([kernel.kallsyms])
        ffffffff8149e344 ip_route_me_harder ([kernel.kallsyms])

and

vrf-test  1187 [001] 46887.295933: fib:fib_table_lookup: table 255 oif 0 iif 1 src 10.100.1.254 dst 10.100.1.2 tos 0 scope 0 flags
        ffffffff8143922c perf_trace_fib_table_lookup ([kernel.kallsyms])
        ffffffff81493aac fib_table_lookup ([kernel.kallsyms])
        ffffffff814998ff fib4_rule_action ([kernel.kallsyms])
        ffffffff81437f35 fib_rules_lookup ([kernel.kallsyms])
        ffffffff81499758 __fib_lookup ([kernel.kallsyms])
        ffffffff8144f010 fib_lookup.constprop.34 ([kernel.kallsyms])
        ffffffff8144f759 __ip_route_output_key_hash ([kernel.kallsyms])
        ffffffff8144fc6a ip_route_output_flow ([kernel.kallsyms])
        ffffffff8149e39b ip_route_me_harder ([kernel.kallsyms])

In both cases the lookups are directed to table 255 rather than the
table associated with the device via the L3 domain. Update both
lookups to pull the L3 domain from the dst currently attached to the
skb.
Signed-off-by: NDavid Ahern <dsa@cumulusnetworks.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

We need to zero out the private data area when application switches
connection to different algorithm (TCP_CONGESTION setsockopt).

When congestion ops get assigned at connect time everything is already
zeroed because sk_alloc uses GFP_ZERO flag.  But in the setsockopt case
this contains whatever previous cc placed there.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix a small memory leak that can occur where we leak a fib_alias in the
event of us not being able to insert it into the local table.

Fixes: 0ddcf43d ("ipv4: FIB Local/MAIN table collapse")
Reported-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The patch that removed the FIB offload infrastructure was a bit too
aggressive and also removed code needed to clean up us splitting the table
if additional rules were added.  Specifically the function
fib_trie_flush_external was called at the end of a new rule being added to
flush the foreign trie entries from the main trie.

I updated the code so that we only call fib_trie_flush_external on the main
table so that we flush the entries for local from main.  This way we don't
call it for every rule change which is what was happening previously.

Fixes: 347e3b28 ("switchdev: remove FIB offload infrastructure")
Reported-by: NEric Dumazet <edumazet@google.com>
Cc: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Honor udptable parameter that is passed to __udp*_lib_mcast_deliver(),
otherwise udplite broadcast/multicast use the wrong table and it breaks.

Fixes: 2dc41cff ("udp: Use hash2 for long hash1 chains in __udp*_lib_mcast_deliver.")
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In commit 24cf3af3 ("igmp: call ip_mc_clear_src..."), we forgot to remove
igmpv3_clear_delrec() in ip_mc_down(), which also called ip_mc_clear_src().
This make us clear all IGMPv3 source filter info after NETDEV_DOWN.
Move igmpv3_clear_delrec() to ip_mc_destroy_dev() and then no need
ip_mc_clear_src() in ip_mc_destroy_dev().

On the other hand, we should restore back instead of free all source filter
info in igmpv3_del_delrec(). Or we will not able to restore IGMPv3 source
filter info after NETDEV_UP and NETDEV_POST_TYPE_CHANGE.

Fixes: 24cf3af3 ("igmp: call ip_mc_clear_src() only when ...")
Signed-off-by: NHangbin Liu <liuhangbin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

With syzkaller help, Marco Grassi found a bug in TCP stack,
crashing in tcp_collapse()

Root cause is that sk_filter() can truncate the incoming skb,
but TCP stack was not really expecting this to happen.
It probably was expecting a simple DROP or ACCEPT behavior.

We first need to make sure no part of TCP header could be removed.
Then we need to adjust TCP_SKB_CB(skb)->end_seq

Many thanks to syzkaller team and Marco for giving us a reproducer.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reported-by: NMarco Grassi <marco.gra@gmail.com>
Reported-by: NVladis Dronov <vdronov@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In v2.6, ip_rt_redirect() calls arp_bind_neighbour() which returns 0
and then the state of the neigh for the new_gw is checked. If the state
isn't valid then the redirected route is deleted. This behavior is
maintained up to v3.5.7 by check_peer_redirect() because rt->rt_gateway
is assigned to peer->redirect_learned.a4 before calling
ipv4_neigh_lookup().

After commit 5943634f ("ipv4: Maintain redirect and PMTU info in
struct rtable again."), ipv4_neigh_lookup() is performed without the
rt_gateway assigned to the new_gw. In the case when rt_gateway (old_gw)
isn't zero, the function uses it as the key. The neigh is most likely
valid since the old_gw is the one that sends the ICMP redirect message.
Then the new_gw is assigned to fib_nh_exception. The problem is: the
new_gw ARP may never gets resolved and the traffic is blackholed.

So, use the new_gw for neigh lookup.

Changes from v1:
 - use __ipv4_neigh_lookup instead (per Eric Dumazet).

Fixes: 5943634f ("ipv4: Maintain redirect and PMTU info in struct rtable again.")
Signed-off-by: NStephen Suryaputra Lin <ssurya@ieee.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is a follow-up to commit 9ee6c5dc ("ipv4: allow local
fragmentation in ip_finish_output_gso()"), updating the comment
documenting cases in which fragmentation is needed for egress
GSO packets.
Suggested-by: NShmulik Ladkani <shmulik.ladkani@gmail.com>
Reviewed-by: NShmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: NLance Richardson <lrichard@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Lorenzo noted an Android unit test failed due to e0d56fdd:
"The expectation in the test was that the RST replying to a SYN sent to a
closed port should be generated with oif=0. In other words it should not
prefer the interface where the SYN came in on, but instead should follow
whatever the routing table says it should do."

Revert the change to ip_send_unicast_reply and tcp_v6_send_response such
that the oif in the flow is set to the skb_iif only if skb_iif is an L3
master.

Fixes: e0d56fdd ("net: l3mdev: remove redundant calls")
Reported-by: NLorenzo Colitti <lorenzo@google.com>
Signed-off-by: NDavid Ahern <dsa@cumulusnetworks.com>
Tested-by: NLorenzo Colitti <lorenzo@google.com>
Acked-by: NLorenzo Colitti <lorenzo@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

icmp_send is called in response to some event. The skb may not have
the device set (skb->dev is NULL), but it is expected to have an rt.
Update icmp_route_lookup to use the rt on the skb to determine L3
domain.

Fixes: 613d09b3 ("net: Use VRF device index for lookups on TX")
Signed-off-by: NDavid Ahern <dsa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The display of /proc/net/route has had a couple issues due to the fact that
when I originally rewrote most of fib_trie I made it so that the iterator
was tracking the next value to use instead of the current.

In addition it had an off by 1 error where I was tracking the first piece
of data as position 0, even though in reality that belonged to the
SEQ_START_TOKEN.

This patch updates the code so the iterator tracks the last reported
position and key instead of the next expected position and key.  In
addition it shifts things so that all of the leaves start at 1 instead of
trying to report leaves starting with offset 0 as being valid.  With these
two issues addressed this should resolve any off by one errors that were
present in the display of /proc/net/route.

Fixes: 25b97c01 ("ipv4: off-by-one in continuation handling in /proc/net/route")
Cc: Andy Whitcroft <apw@canonical.com>
Reported-by: NJason Baron <jbaron@akamai.com>
Tested-by: NJason Baron <jbaron@akamai.com>
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After my commit, tcp_sendmsg() might restart its loop after
processing socket backlog.

If sk_err is set, we blindly return an error, even though we
copied data to user space before.

We should instead return number of bytes that could be copied,
otherwise user space might resend data and corrupt the stream.

This might happen if another thread is using recvmsg(MSG_ERRQUEUE)
to process timestamps.

Issue was diagnosed by Soheil and Willem, big kudos to them !

Fixes: d41a69f1 ("tcp: make tcp_sendmsg() aware of socket backlog")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Soheil Hassas Yeganeh <soheil@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Tested-by: NSoheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some configurations (e.g. geneve interface with default
MTU of 1500 over an ethernet interface with 1500 MTU) result
in the transmission of packets that exceed the configured MTU.
While this should be considered to be a "bad" configuration,
it is still allowed and should not result in the sending
of packets that exceed the configured MTU.

Fix by dropping the assumption in ip_finish_output_gso() that
locally originated gso packets will never need fragmentation.
Basic testing using iperf (observing CPU usage and bandwidth)
have shown no measurable performance impact for traffic not
requiring fragmentation.

Fixes: c7ba65d7 ("net: ip: push gso skb forwarding handling down the stack")
Reported-by: NJan Tluka <jtluka@redhat.com>
Signed-off-by: NLance Richardson <lrichard@redhat.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Imagine initial value of max_skb_frags is 17, and last
skb in write queue has 15 frags.

Then max_skb_frags is lowered to 14 or smaller value.

tcp_sendmsg() will then be allowed to add additional page frags
and eventually go past MAX_SKB_FRAGS, overflowing struct
skb_shared_info.

Fixes: 5f74f82e ("net:Add sysctl_max_skb_frags")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Hans Westgaard Ry <hans.westgaard.ry@oracle.com>
Cc: Håkon Bugge <haakon.bugge@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Andrey reported this kernel warning:

  WARNING: CPU: 0 PID: 4608 at kernel/sched/core.c:7724
  __might_sleep+0x14c/0x1a0 kernel/sched/core.c:7719
  do not call blocking ops when !TASK_RUNNING; state=1 set at
  [<ffffffff811f5a5c>] prepare_to_wait+0xbc/0x210
  kernel/sched/wait.c:178
  Modules linked in:
  CPU: 0 PID: 4608 Comm: syz-executor Not tainted 4.9.0-rc2+ #320
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
   ffff88006625f7a0 ffffffff81b46914 ffff88006625f818 0000000000000000
   ffffffff84052960 0000000000000000 ffff88006625f7e8 ffffffff81111237
   ffff88006aceac00 ffffffff00001e2c ffffed000cc4beff ffffffff84052960
  Call Trace:
   [<     inline     >] __dump_stack lib/dump_stack.c:15
   [<ffffffff81b46914>] dump_stack+0xb3/0x10f lib/dump_stack.c:51
   [<ffffffff81111237>] __warn+0x1a7/0x1f0 kernel/panic.c:550
   [<ffffffff8111132c>] warn_slowpath_fmt+0xac/0xd0 kernel/panic.c:565
   [<ffffffff811922fc>] __might_sleep+0x14c/0x1a0 kernel/sched/core.c:7719
   [<     inline     >] slab_pre_alloc_hook mm/slab.h:393
   [<     inline     >] slab_alloc_node mm/slub.c:2634
   [<     inline     >] slab_alloc mm/slub.c:2716
   [<ffffffff81508da0>] __kmalloc_track_caller+0x150/0x2a0 mm/slub.c:4240
   [<ffffffff8146be14>] kmemdup+0x24/0x50 mm/util.c:113
   [<ffffffff8388b2cf>] dccp_feat_clone_sp_val.part.5+0x4f/0xe0 net/dccp/feat.c:374
   [<     inline     >] dccp_feat_clone_sp_val net/dccp/feat.c:1141
   [<     inline     >] dccp_feat_change_recv net/dccp/feat.c:1141
   [<ffffffff8388d491>] dccp_feat_parse_options+0xaa1/0x13d0 net/dccp/feat.c:1411
   [<ffffffff83894f01>] dccp_parse_options+0x721/0x1010 net/dccp/options.c:128
   [<ffffffff83891280>] dccp_rcv_state_process+0x200/0x15b0 net/dccp/input.c:644
   [<ffffffff838b8a94>] dccp_v4_do_rcv+0xf4/0x1a0 net/dccp/ipv4.c:681
   [<     inline     >] sk_backlog_rcv ./include/net/sock.h:872
   [<ffffffff82b7ceb6>] __release_sock+0x126/0x3a0 net/core/sock.c:2044
   [<ffffffff82b7d189>] release_sock+0x59/0x1c0 net/core/sock.c:2502
   [<     inline     >] inet_wait_for_connect net/ipv4/af_inet.c:547
   [<ffffffff8316b2a2>] __inet_stream_connect+0x5d2/0xbb0 net/ipv4/af_inet.c:617
   [<ffffffff8316b8d5>] inet_stream_connect+0x55/0xa0 net/ipv4/af_inet.c:656
   [<ffffffff82b705e4>] SYSC_connect+0x244/0x2f0 net/socket.c:1533
   [<ffffffff82b72dd4>] SyS_connect+0x24/0x30 net/socket.c:1514
   [<ffffffff83fbf701>] entry_SYSCALL_64_fastpath+0x1f/0xc2
  arch/x86/entry/entry_64.S:209

Unlike commit 26cabd31
("sched, net: Clean up sk_wait_event() vs. might_sleep()"), the
sleeping function is called before schedule_timeout(), this is indeed
a bug. Fix this by moving the wait logic to the new API, it is similar
to commit ff960a73
("netdev, sched/wait: Fix sleeping inside wait event").
Reported-by: NAndrey Konovalov <andreyknvl@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If a congestion control module doesn't provide .undo_cwnd function,
tcp_undo_cwnd_reduction() will set cwnd to

   tp->snd_cwnd = max(tp->snd_cwnd, tp->snd_ssthresh << 1);

... which makes sense for reno (it sets ssthresh to half the current cwnd),
but it makes no sense for dctcp, which sets ssthresh based on the current
congestion estimate.

This can cause severe growth of cwnd (eventually overflowing u32).

Fix this by saving last cwnd on loss and restore cwnd based on that,
similar to cubic and other algorithms.

Fixes: e3118e83 ("net: tcp: add DCTCP congestion control algorithm")
Cc: Lawrence Brakmo <brakmo@fb.com>
Cc: Andrew Shewmaker <agshew@gmail.com>
Cc: Glenn Judd <glenn.judd@morganstanley.com>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The NFTA_DUP_SREG_DEV attribute is not a must option, so we should use it
in routing lookup only when the user specify it.

Fixes: d877f071 ("netfilter: nf_tables: add nft_dup expression")
Signed-off-by: NLiping Zhang <zlpnobody@gmail.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

First bug was added in commit ad6f939a ("ip: Add offset parameter to
ip_cmsg_recv") : Tom missed that ipv4 udp messages could be received on
AF_INET6 socket. ip_cmsg_recv(msg, skb) should have been replaced by
ip_cmsg_recv_offset(msg, skb, sizeof(struct udphdr));

Then commit e6afc8ac ("udp: remove headers from UDP packets before
queueing") forgot to adjust the offsets now UDP headers are pulled
before skb are put in receive queue.

Fixes: ad6f939a ("ip: Add offset parameter to ip_cmsg_recv")
Fixes: e6afc8ac ("udp: remove headers from UDP packets before queueing")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Sam Kumar <samanthakumar@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Tested-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit a681574c
("ipv4: disable BH in set_ping_group_range()") because we never
read ping_group_range in BH context (unlike local_port_range).

Then, since we already have a lock for ping_group_range, those
using ip_local_ports.lock for ping_group_range are clearly typos.

We might consider to share a same lock for both ping_group_range
and local_port_range w.r.t. space saving, but that should be for
net-next.

Fixes: a681574c ("ipv4: disable BH in set_ping_group_range()")
Fixes: ba6b918a ("ping: move ping_group_range out of CONFIG_SYSCTL")
Cc: Eric Dumazet <edumazet@google.com>
Cc: Eric Salo <salo@google.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In commit 4ee3bd4a ("ipv4: disable BH when changing ip local port
range") Cong added BH protection in set_local_port_range() but missed
that same fix was needed in set_ping_group_range()

Fixes: b8f1a556 ("udp: Add function to make source port for UDP tunnels")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reported-by: NEric Salo <salo@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Baozeng Ding reported KASAN traces showing uses after free in
udp_lib_get_port() and other related UDP functions.

A CONFIG_DEBUG_PAGEALLOC=y kernel would eventually crash.

I could write a reproducer with two threads doing :

static int sock_fd;
static void *thr1(void *arg)
{
	for (;;) {
		connect(sock_fd, (const struct sockaddr *)arg,
			sizeof(struct sockaddr_in));
	}
}

static void *thr2(void *arg)
{
	struct sockaddr_in unspec;

	for (;;) {
		memset(&unspec, 0, sizeof(unspec));
	        connect(sock_fd, (const struct sockaddr *)&unspec,
			sizeof(unspec));
        }
}

Problem is that udp_disconnect() could run without holding socket lock,
and this was causing list corruptions.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reported-by: NBaozeng Ding <sploving1@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently, GRO can do unlimited recursion through the gro_receive
handlers.  This was fixed for tunneling protocols by limiting tunnel GRO
to one level with encap_mark, but both VLAN and TEB still have this
problem.  Thus, the kernel is vulnerable to a stack overflow, if we
receive a packet composed entirely of VLAN headers.

This patch adds a recursion counter to the GRO layer to prevent stack
overflow.  When a gro_receive function hits the recursion limit, GRO is
aborted for this skb and it is processed normally.  This recursion
counter is put in the GRO CB, but could be turned into a percpu counter
if we run out of space in the CB.

Thanks to Vladimír Beneš <vbenes@redhat.com> for the initial bug report.

Fixes: CVE-2016-7039
Fixes: 9b174d88 ("net: Add Transparent Ethernet Bridging GRO support.")
Fixes: 66e5133f ("vlan: Add GRO support for non hardware accelerated vlan")
Signed-off-by: NSabrina Dubroca <sd@queasysnail.net>
Reviewed-by: NJiri Benc <jbenc@redhat.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: NTom Herbert <tom@herbertland.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since commit b2fb4f54 ("tcp: uninline tcp_prequeue()") we no longer
access sysctl_tcp_low_latency from a module.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove the unused but set variable icsk in listening_get_next to fix the
following GCC warning when building with 'W=1':

  net/ipv4/tcp_ipv4.c: In function ‘listening_get_next’:
  net/ipv4/tcp_ipv4.c:1890:31: warning: variable ‘icsk’ set but not used [-Wunused-but-set-variable]
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove the unused but set variable dev in ip_do_fragment to fix the
following GCC warning when building with 'W=1':

  net/ipv4/ip_output.c: In function ‘ip_do_fragment’:
  net/ipv4/ip_output.c:541:21: warning: variable ‘dev’ set but not used [-Wunused-but-set-variable]
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently, socket lookups for l3mdev (vrf) use cases can match a socket
that is bound to a port but not a device (ie., a global socket). If the
sysctl tcp_l3mdev_accept is not set this leads to ack packets going out
based on the main table even though the packet came in from an L3 domain.
The end result is that the connection does not establish creating
confusion for users since the service is running and a socket shows in
ss output. Fix by requiring an exact dif to sk_bound_dev_if match if the
skb came through an interface enslaved to an l3mdev device and the
tcp_l3mdev_accept is not set.

skb's through an l3mdev interface are marked by setting a flag in
inet{6}_skb_parm. The IPv6 variant is already set; this patch adds the
flag for IPv4. Using an skb flag avoids a device lookup on the dif. The
flag is set in the VRF driver using the IP{6}CB macros. For IPv4, the
inet_skb_parm struct is moved in the cb per commit 971f10ec, so the
match function in the TCP stack needs to use TCP_SKB_CB. For IPv6, the
move is done after the socket lookup, so IP6CB is used.

The flags field in inet_skb_parm struct needs to be increased to add
another flag. There is currently a 1-byte hole following the flags,
so it can be expanded to u16 without increasing the size of the struct.

Fixes: 193125db ("net: Introduce VRF device driver")
Signed-off-by: NDavid Ahern <dsa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit e0d56fdd was a bit aggressive removing l3mdev calls in
the IPv4 stack. If the fib_lookup fails we do not want to drop to
make_route if the oif is an l3mdev device.

Also reverts 19664c6a ("net: l3mdev: Remove netif_index_is_l3_master")
which removed netif_index_is_l3_master.

Fixes: e0d56fdd ("net: l3mdev: remove redundant calls")
Signed-off-by: NDavid Ahern <dsa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Current supplementary groups code can massively overallocate memory and
is implemented in a way so that access to individual gid is done via 2D
array.

If number of gids is <= 32, memory allocation is more or less tolerable
(140/148 bytes).  But if it is not, code allocates full page (!)
regardless and, what's even more fun, doesn't reuse small 32-entry
array.

2D array means dependent shifts, loads and LEAs without possibility to
optimize them (gid is never known at compile time).

All of the above is unnecessary.  Switch to the usual
trailing-zero-len-array scheme.  Memory is allocated with
kmalloc/vmalloc() and only as much as needed.  Accesses become simpler
(LEA 8(gi,idx,4) or even without displacement).

Maximum number of gids is 65536 which translates to 256KB+8 bytes.  I
think kernel can handle such allocation.

On my usual desktop system with whole 9 (nine) aux groups, struct
group_info shrinks from 148 bytes to 44 bytes, yay!

Nice side effects:

 - "gi->gid[i]" is shorter than "GROUP_AT(gi, i)", less typing,

 - fix little mess in net/ipv4/ping.c
   should have been using GROUP_AT macro but this point becomes moot,

 - aux group allocation is persistent and should be accounted as such.

Link: http://lkml.kernel.org/r/20160817201927.GA2096@p183.telecom.bySigned-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Cc: Vasily Kulikov <segoon@openwall.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The cgroup core and the memory controller need to track socket ownership
for different purposes, but the tracking sites being entirely different
is kind of ugly.

Be a better citizen and rename the memory controller callbacks to match
the cgroup core callbacks, then move them to the same place.

[akpm@linux-foundation.org: coding-style fixes]
Link: http://lkml.kernel.org/r/20160914194846.11153-3-hannes@cmpxchg.orgSigned-off-by: NJohannes Weiner <hannes@cmpxchg.org>
Acked-by: NTejun Heo <tj@kernel.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

since pipe_lock is the outermost now, we don't need to drop/regain
socket locks around the call of splice_to_pipe() from skb_splice_bits(),
which kills the need to have a socket-specific callback; we can just
call splice_to_pipe() and be done with that.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

This is to suppress the checkpatch.pl warning "Comparison to NULL
could be written". No functional changes here.
Signed-off-by: NJia He <hejianet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>