Commit Graph

6302 Commits

Author SHA1 Message Date
Shmulik Ladkani
1b4e5ad5d6 ipv6: sr: properly initialize flowi6 prior passing to ip6_route_output
In 'seg6_output', stack variable 'struct flowi6 fl6' was missing
initialization.

Fixes: 6c8702c60b ("ipv6: sr: add support for SRH encapsulation and injection with lwtunnels")
Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-07 12:22:39 -08:00
Jiri Wiesner
ebaf39e603 ipv4: ipv6: netfilter: Adjust the frag mem limit when truesize changes
The *_frag_reasm() functions are susceptible to miscalculating the byte
count of packet fragments in case the truesize of a head buffer changes.
The truesize member may be changed by the call to skb_unclone(), leaving
the fragment memory limit counter unbalanced even if all fragments are
processed. This miscalculation goes unnoticed as long as the network
namespace which holds the counter is not destroyed.

Should an attempt be made to destroy a network namespace that holds an
unbalanced fragment memory limit counter the cleanup of the namespace
never finishes. The thread handling the cleanup gets stuck in
inet_frags_exit_net() waiting for the percpu counter to reach zero. The
thread is usually in running state with a stacktrace similar to:

 PID: 1073   TASK: ffff880626711440  CPU: 1   COMMAND: "kworker/u48:4"
  #5 [ffff880621563d48] _raw_spin_lock at ffffffff815f5480
  #6 [ffff880621563d48] inet_evict_bucket at ffffffff8158020b
  #7 [ffff880621563d80] inet_frags_exit_net at ffffffff8158051c
  #8 [ffff880621563db0] ops_exit_list at ffffffff814f5856
  #9 [ffff880621563dd8] cleanup_net at ffffffff814f67c0
 #10 [ffff880621563e38] process_one_work at ffffffff81096f14

It is not possible to create new network namespaces, and processes
that call unshare() end up being stuck in uninterruptible sleep state
waiting to acquire the net_mutex.

The bug was observed in the IPv6 netfilter code by Per Sundstrom.
I thank him for his analysis of the problem. The parts of this patch
that apply to IPv4 and IPv6 fragment reassembly are preemptive measures.

Signed-off-by: Jiri Wiesner <jwiesner@suse.com>
Reported-by: Per Sundstrom <per.sundstrom@redqube.se>
Acked-by: Peter Oskolkov <posk@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-05 20:44:46 -08:00
Edward Cree
22f6bbb7bc net: use skb_list_del_init() to remove from RX sublists
list_del() leaves the skb->next pointer poisoned, which can then lead to
 a crash in e.g. OVS forwarding.  For example, setting up an OVS VXLAN
 forwarding bridge on sfc as per:

========
$ ovs-vsctl show
5dfd9c47-f04b-4aaa-aa96-4fbb0a522a30
    Bridge "br0"
        Port "br0"
            Interface "br0"
                type: internal
        Port "enp6s0f0"
            Interface "enp6s0f0"
        Port "vxlan0"
            Interface "vxlan0"
                type: vxlan
                options: {key="1", local_ip="10.0.0.5", remote_ip="10.0.0.4"}
    ovs_version: "2.5.0"
========
(where 10.0.0.5 is an address on enp6s0f1)
and sending traffic across it will lead to the following panic:
========
general protection fault: 0000 [#1] SMP PTI
CPU: 5 PID: 0 Comm: swapper/5 Not tainted 4.20.0-rc3-ehc+ #701
Hardware name: Dell Inc. PowerEdge R710/0M233H, BIOS 6.4.0 07/23/2013
RIP: 0010:dev_hard_start_xmit+0x38/0x200
Code: 53 48 89 fb 48 83 ec 20 48 85 ff 48 89 54 24 08 48 89 4c 24 18 0f 84 ab 01 00 00 48 8d 86 90 00 00 00 48 89 f5 48 89 44 24 10 <4c> 8b 33 48 c7 03 00 00 00 00 48 8b 05 c7 d1 b3 00 4d 85 f6 0f 95
RSP: 0018:ffff888627b437e0 EFLAGS: 00010202
RAX: 0000000000000000 RBX: dead000000000100 RCX: ffff88862279c000
RDX: ffff888614a342c0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff888618a88000 R08: 0000000000000001 R09: 00000000000003e8
R10: 0000000000000000 R11: ffff888614a34140 R12: 0000000000000000
R13: 0000000000000062 R14: dead000000000100 R15: ffff888616430000
FS:  0000000000000000(0000) GS:ffff888627b40000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6d2bc6d000 CR3: 000000000200a000 CR4: 00000000000006e0
Call Trace:
 <IRQ>
 __dev_queue_xmit+0x623/0x870
 ? masked_flow_lookup+0xf7/0x220 [openvswitch]
 ? ep_poll_callback+0x101/0x310
 do_execute_actions+0xaba/0xaf0 [openvswitch]
 ? __wake_up_common+0x8a/0x150
 ? __wake_up_common_lock+0x87/0xc0
 ? queue_userspace_packet+0x31c/0x5b0 [openvswitch]
 ovs_execute_actions+0x47/0x120 [openvswitch]
 ovs_dp_process_packet+0x7d/0x110 [openvswitch]
 ovs_vport_receive+0x6e/0xd0 [openvswitch]
 ? dst_alloc+0x64/0x90
 ? rt_dst_alloc+0x50/0xd0
 ? ip_route_input_slow+0x19a/0x9a0
 ? __udp_enqueue_schedule_skb+0x198/0x1b0
 ? __udp4_lib_rcv+0x856/0xa30
 ? __udp4_lib_rcv+0x856/0xa30
 ? cpumask_next_and+0x19/0x20
 ? find_busiest_group+0x12d/0xcd0
 netdev_frame_hook+0xce/0x150 [openvswitch]
 __netif_receive_skb_core+0x205/0xae0
 __netif_receive_skb_list_core+0x11e/0x220
 netif_receive_skb_list+0x203/0x460
 ? __efx_rx_packet+0x335/0x5e0 [sfc]
 efx_poll+0x182/0x320 [sfc]
 net_rx_action+0x294/0x3c0
 __do_softirq+0xca/0x297
 irq_exit+0xa6/0xb0
 do_IRQ+0x54/0xd0
 common_interrupt+0xf/0xf
 </IRQ>
========
So, in all listified-receive handling, instead pull skbs off the lists with
 skb_list_del_init().

Fixes: 9af86f9338 ("net: core: fix use-after-free in __netif_receive_skb_list_core")
Fixes: 7da517a3bc ("net: core: Another step of skb receive list processing")
Fixes: a4ca8b7df7 ("net: ipv4: fix drop handling in ip_list_rcv() and ip_list_rcv_finish()")
Fixes: d8269e2cbf ("net: ipv6: listify ipv6_rcv() and ip6_rcv_finish()")
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-05 16:22:05 -08:00
David S. Miller
e9d8faf93d Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

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

The following patchset contains Netfilter fixes for net:

1) Disable BH while holding list spinlock in nf_conncount, from
   Taehee Yoo.

2) List corruption in nf_conncount, also from Taehee.

3) Fix race that results in leaving around an empty list node in
   nf_conncount, from Taehee Yoo.

4) Proper chain handling for inactive chains from the commit path,
   from Florian Westphal. This includes a selftest for this.

5) Do duplicate rule handles when replacing rules, also from Florian.

6) Remove net_exit path in xt_RATEEST that results in splat, from Taehee.

7) Possible use-after-free in nft_compat when releasing extensions.
   From Florian.

8) Memory leak in xt_hashlimit, from Taehee.

9) Call ip_vs_dst_notifier after ipv6_dev_notf, from Xin Long.

10) Fix cttimeout with udplite and gre, from Florian.

11) Preserve oif for IPv6 link-local generated traffic from mangle
    table, from Alin Nastac.

12) Missing error handling in masquerade notifiers, from Taehee Yoo.

13) Use mutex to protect registration/unregistration of masquerade
    extensions in order to prevent a race, from Taehee.

14) Incorrect condition check in tree_nodes_free(), also from Taehee.

15) Fix chain counter leak in rule replacement path, from Taehee.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-28 11:02:45 -08:00
Taehee Yoo
095faf45e6 netfilter: nat: fix double register in masquerade modules
There is a reference counter to ensure that masquerade modules register
notifiers only once. However, the existing reference counter approach is
not safe, test commands are:

   while :
   do
   	   modprobe ip6t_MASQUERADE &
	   modprobe nft_masq_ipv6 &
	   modprobe -rv ip6t_MASQUERADE &
	   modprobe -rv nft_masq_ipv6 &
   done

numbers below represent the reference counter.
--------------------------------------------------------
CPU0        CPU1        CPU2        CPU3        CPU4
[insmod]    [insmod]    [rmmod]     [rmmod]     [insmod]
--------------------------------------------------------
0->1
register    1->2
            returns     2->1
			returns     1->0
                                                0->1
                                                register <--
                                    unregister
--------------------------------------------------------

The unregistation of CPU3 should be processed before the
registration of CPU4.

In order to fix this, use a mutex instead of reference counter.

splat looks like:
[  323.869557] watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [modprobe:1381]
[  323.869574] Modules linked in: nf_tables(+) nf_nat_ipv6(-) nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 n]
[  323.869574] irq event stamp: 194074
[  323.898930] hardirqs last  enabled at (194073): [<ffffffff90004a0d>] trace_hardirqs_on_thunk+0x1a/0x1c
[  323.898930] hardirqs last disabled at (194074): [<ffffffff90004a29>] trace_hardirqs_off_thunk+0x1a/0x1c
[  323.898930] softirqs last  enabled at (182132): [<ffffffff922006ec>] __do_softirq+0x6ec/0xa3b
[  323.898930] softirqs last disabled at (182109): [<ffffffff90193426>] irq_exit+0x1a6/0x1e0
[  323.898930] CPU: 0 PID: 1381 Comm: modprobe Not tainted 4.20.0-rc2+ #27
[  323.898930] RIP: 0010:raw_notifier_chain_register+0xea/0x240
[  323.898930] Code: 3c 03 0f 8e f2 00 00 00 44 3b 6b 10 7f 4d 49 bc 00 00 00 00 00 fc ff df eb 22 48 8d 7b 10 488
[  323.898930] RSP: 0018:ffff888101597218 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13
[  323.898930] RAX: 0000000000000000 RBX: ffffffffc04361c0 RCX: 0000000000000000
[  323.898930] RDX: 1ffffffff26132ae RSI: ffffffffc04aa3c0 RDI: ffffffffc04361d0
[  323.898930] RBP: ffffffffc04361c8 R08: 0000000000000000 R09: 0000000000000001
[  323.898930] R10: ffff8881015972b0 R11: fffffbfff26132c4 R12: dffffc0000000000
[  323.898930] R13: 0000000000000000 R14: 1ffff110202b2e44 R15: ffffffffc04aa3c0
[  323.898930] FS:  00007f813ed41540(0000) GS:ffff88811ae00000(0000) knlGS:0000000000000000
[  323.898930] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  323.898930] CR2: 0000559bf2c9f120 CR3: 000000010bc80000 CR4: 00000000001006f0
[  323.898930] Call Trace:
[  323.898930]  ? atomic_notifier_chain_register+0x2d0/0x2d0
[  323.898930]  ? down_read+0x150/0x150
[  323.898930]  ? sched_clock_cpu+0x126/0x170
[  323.898930]  ? nf_tables_core_module_init+0xe4/0xe4 [nf_tables]
[  323.898930]  ? nf_tables_core_module_init+0xe4/0xe4 [nf_tables]
[  323.898930]  register_netdevice_notifier+0xbb/0x790
[  323.898930]  ? __dev_close_many+0x2d0/0x2d0
[  323.898930]  ? __mutex_unlock_slowpath+0x17f/0x740
[  323.898930]  ? wait_for_completion+0x710/0x710
[  323.898930]  ? nf_tables_core_module_init+0xe4/0xe4 [nf_tables]
[  323.898930]  ? up_write+0x6c/0x210
[  323.898930]  ? nf_tables_core_module_init+0xe4/0xe4 [nf_tables]
[  324.127073]  ? nf_tables_core_module_init+0xe4/0xe4 [nf_tables]
[  324.127073]  nft_chain_filter_init+0x1e/0xe8a [nf_tables]
[  324.127073]  nf_tables_module_init+0x37/0x92 [nf_tables]
[ ... ]

Fixes: 8dd33cc93e ("netfilter: nf_nat: generalize IPv4 masquerading support for nf_tables")
Fixes: be6b635cd6 ("netfilter: nf_nat: generalize IPv6 masquerading support for nf_tables")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-11-27 00:36:46 +01:00
Taehee Yoo
584eab291c netfilter: add missing error handling code for register functions
register_{netdevice/inetaddr/inet6addr}_notifier may return an error
value, this patch adds the code to handle these error paths.

Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-11-27 00:35:19 +01:00
Alin Nastac
508b09046c netfilter: ipv6: Preserve link scope traffic original oif
When ip6_route_me_harder is invoked, it resets outgoing interface of:
  - link-local scoped packets sent by neighbor discovery
  - multicast packets sent by MLD host
  - multicast packets send by MLD proxy daemon that sets outgoing
    interface through IPV6_PKTINFO ipi6_ifindex

Link-local and multicast packets must keep their original oif after
ip6_route_me_harder is called.

Signed-off-by: Alin Nastac <alin.nastac@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-11-27 00:12:20 +01:00
Willem de Bruijn
aba36930a3 net: always initialize pagedlen
In ip packet generation, pagedlen is initialized for each skb at the
start of the loop in __ip(6)_append_data, before label alloc_new_skb.

Depending on compiler options, code can be generated that jumps to
this label, triggering use of an an uninitialized variable.

In practice, at -O2, the generated code moves the initialization below
the label. But the code should not rely on that for correctness.

Fixes: 15e36f5b8e ("udp: paged allocation with gso")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-24 17:42:57 -08:00
Hangbin Liu
896585d48e net/ipv6: re-do dad when interface has IFF_NOARP flag change
When we add a new IPv6 address, we should also join corresponding solicited-node
multicast address, unless the interface has IFF_NOARP flag, as function
addrconf_join_solict() did. But if we remove IFF_NOARP flag later, we do
not do dad and add the mcast address. So we will drop corresponding neighbour
discovery message that came from other nodes.

A typical example is after creating a ipvlan with mode l3, setting up an ipv6
address and changing the mode to l2. Then we will not be able to ping this
address as the interface doesn't join related solicited-node mcast address.

Fix it by re-doing dad when interface changed IFF_NOARP flag. Then we will add
corresponding mcast group and check if there is a duplicate address on the
network.

Reported-by: Jianlin Shi <jishi@redhat.com>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-23 11:17:56 -08:00
David Ahern
7ddacfa564 ipv6: Fix PMTU updates for UDP/raw sockets in presence of VRF
Preethi reported that PMTU discovery for UDP/raw applications is not
working in the presence of VRF when the socket is not bound to a device.
The problem is that ip6_sk_update_pmtu does not consider the L3 domain
of the skb device if the socket is not bound. Update the function to
set oif to the L3 master device if relevant.

Fixes: ca254490c8 ("net: Add VRF support to IPv6 stack")
Reported-by: Preethi Ramachandra <preethir@juniper.net>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-18 19:02:56 -08:00
Xin Long
761f60261b ipv6: fix a dst leak when removing its exception
These is no need to hold dst before calling rt6_remove_exception_rt().
The call to dst_hold_safe() in ip6_link_failure() was for ip6_del_rt(),
which has been removed in Commit 93531c6743 ("net/ipv6: separate
handling of FIB entries from dst based routes"). Otherwise, it will
cause a dst leak.

This patch is to simply remove the dst_hold_safe() call before calling
rt6_remove_exception_rt() and also do the same in ip6_del_cached_rt().
It's safe, because the removal of the exception that holds its dst's
refcnt is protected by rt6_exception_lock.

Fixes: 93531c6743 ("net/ipv6: separate handling of FIB entries from dst based routes")
Fixes: 23fb93a4d3 ("net/ipv6: Cleanup exception and cache route handling")
Reported-by: Li Shuang <shuali@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-16 19:44:15 -08:00
David S. Miller
a422757e8c Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

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

The following patchset contains the first batch of Netfilter fixes for
your net tree:

1) Fix splat with IPv6 defragmenting locally generated fragments,
   from Florian Westphal.

2) Fix Incorrect check for missing attribute in nft_osf.

3) Missing INT_MIN & INT_MAX definition for netfilter bridge uapi
   header, from Jiri Slaby.

4) Revert map lookup in nft_numgen, this is already possible with
   the existing infrastructure without this extension.

5) Fix wrong listing of set reference counter, make counter
   synchronous again, from Stefano Brivio.

6) Fix CIDR 0 in hash:net,port,net, from Eric Westbrook.

7) Fix allocation failure with large set, use kvcalloc().
   From Andrey Ryabinin.

8) No need to disable BH when fetch ip set comment, patch from
   Jozsef Kadlecsik.

9) Sanity check for valid sysfs entry in xt_IDLETIMER, from
   Taehee Yoo.

10) Fix suspicious rcu usage via ip_set() macro at netlink dump,
    from Jozsef Kadlecsik.

11) Fix setting default timeout via nfnetlink_cttimeout, this
    comes with preparation patch to add nf_{tcp,udp,...}_pernet()
    helper.

12) Allow ebtables table nat to be of filter type via nft_compat.
    From Florian Westphal.

13) Incorrect calculation of next bucket in early_drop, do no bump
    hash value, update bucket counter instead. From Vasily Khoruzhick.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-05 17:19:25 -08:00
Alexey Kodanev
e22d0bfa09 ipv6: properly check return value in inet6_dump_all()
Make sure we call fib6_dump_end() if it happens that skb->len
is zero. rtnl_dump_all() can reset cb->args on the next loop
iteration there.

Fixes: 08e814c9e8 ("net/ipv6: Bail early if user only wants cloned entries")
Fixes: ae677bbb44 ("net: Don't return invalid table id error when dumping all families")
Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-05 17:04:54 -08:00
Jeff Barnhill
6915ed86cc net/ipv6: Move anycast init/cleanup functions out of CONFIG_PROC_FS
Move the anycast.c init and cleanup functions which were inadvertently
added inside the CONFIG_PROC_FS definition.

Fixes: 2384d02520 ("net/ipv6: Add anycast addresses to a global hashtable")
Signed-off-by: Jeff Barnhill <0xeffeff@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-05 13:36:27 -08:00
Jeff Barnhill
2384d02520 net/ipv6: Add anycast addresses to a global hashtable
icmp6_send() function is expensive on systems with a large number of
interfaces. Every time it’s called, it has to verify that the source
address does not correspond to an existing anycast address by looping
through every device and every anycast address on the device.  This can
result in significant delays for a CPU when there are a large number of
neighbors and ND timers are frequently timing out and calling
neigh_invalidate().

Add anycast addresses to a global hashtable to allow quick searching for
matching anycast addresses.  This is based on inet6_addr_lst in addrconf.c.

Signed-off-by: Jeff Barnhill <0xeffeff@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-02 23:54:56 -07:00
Mike Manning
f64bf6b8ae net: allow traceroute with a specified interface in a vrf
Traceroute executed in a vrf succeeds if no device is given or if the
vrf is given as the device, but fails if the interface is given as the
device. This is for default UDP probes, it succeeds for TCP SYN or ICMP
ECHO probes. As the skb bound dev is the interface and the sk dev is
the vrf, sk lookup fails for ICMP_DEST_UNREACH and ICMP_TIME_EXCEEDED
messages. The solution is for the secondary dev to be passed so that
the interface is available for the device match to succeed, in the same
way as is already done for non-error cases.

Signed-off-by: Mike Manning <mmanning@vyatta.att-mail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-26 16:03:08 -07:00
Stefano Brivio
ee1abcf689 ipv6/ndisc: Preserve IPv6 control buffer if protocol error handlers are called
Commit a61bbcf28a ("[NET]: Store skb->timestamp as offset to a base
timestamp") introduces a neighbour control buffer and zeroes it out in
ndisc_rcv(), as ndisc_recv_ns() uses it.

Commit f2776ff047 ("[IPV6]: Fix address/interface handling in UDP and
DCCP, according to the scoping architecture.") introduces the usage of the
IPv6 control buffer in protocol error handlers (e.g. inet6_iif() in
present-day __udp6_lib_err()).

Now, with commit b94f1c0904 ("ipv6: Use icmpv6_notify() to propagate
redirect, instead of rt6_redirect()."), we call protocol error handlers
from ndisc_redirect_rcv(), after the control buffer is already stolen and
some parts are already zeroed out. This implies that inet6_iif() on this
path will always return zero.

This gives unexpected results on UDP socket lookup in __udp6_lib_err(), as
we might actually need to match sockets for a given interface.

Instead of always claiming the control buffer in ndisc_rcv(), do that only
when needed.

Fixes: b94f1c0904 ("ipv6: Use icmpv6_notify() to propagate redirect, instead of rt6_redirect().")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-26 15:58:06 -07:00
Bjørn Mork
bf4cc40e93 net/{ipv4,ipv6}: Do not put target net if input nsid is invalid
The cleanup path will put the target net when netnsid is set.  So we must
reset netnsid if the input is invalid.

Fixes: d7e38611b8 ("net/ipv4: Put target net when address dump fails due to bad attributes")
Fixes: 242afaa696 ("net/ipv6: Put target net when address dump fails due to bad attributes")
Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-25 16:21:31 -07:00
Florian Westphal
61792b6774 netfilter: ipv6: fix oops when defragmenting locally generated fragments
Unlike ipv4 and normal ipv6 defrag, netfilter ipv6 defragmentation did
not save/restore skb->dst.

This causes oops when handling locally generated ipv6 fragments, as
output path needs a valid dst.

Reported-by: Maciej Żenczykowski <zenczykowski@gmail.com>
Fixes: 84379c9afe ("netfilter: ipv6: nf_defrag: drop skb dst before queueing")
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-10-25 10:18:26 +02:00
David Ahern
4ed591c8ab net/ipv6: Allow onlink routes to have a device mismatch if it is the default route
The intent of ip6_route_check_nh_onlink is to make sure the gateway
given for an onlink route is not actually on a connected route for
a different interface (e.g., 2001:db8:1::/64 is on dev eth1 and then
an onlink route has a via 2001:db8:1::1 dev eth2). If the gateway
lookup hits the default route then it most likely will be a different
interface than the onlink route which is ok.

Update ip6_route_check_nh_onlink to disregard the device mismatch
if the gateway lookup hits the default route. Turns out the existing
onlink tests are passing because there is no default route or it is
an unreachable default, so update the onlink tests to have a default
route other than unreachable.

Fixes: fc1e64e109 ("net/ipv6: Add support for onlink flag")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-24 14:36:38 -07:00
Sean Tranchetti
db4f1be3ca net: udp: fix handling of CHECKSUM_COMPLETE packets
Current handling of CHECKSUM_COMPLETE packets by the UDP stack is
incorrect for any packet that has an incorrect checksum value.

udp4/6_csum_init() will both make a call to
__skb_checksum_validate_complete() to initialize/validate the csum
field when receiving a CHECKSUM_COMPLETE packet. When this packet
fails validation, skb->csum will be overwritten with the pseudoheader
checksum so the packet can be fully validated by software, but the
skb->ip_summed value will be left as CHECKSUM_COMPLETE so that way
the stack can later warn the user about their hardware spewing bad
checksums. Unfortunately, leaving the SKB in this state can cause
problems later on in the checksum calculation.

Since the the packet is still marked as CHECKSUM_COMPLETE,
udp_csum_pull_header() will SUBTRACT the checksum of the UDP header
from skb->csum instead of adding it, leaving us with a garbage value
in that field. Once we try to copy the packet to userspace in the
udp4/6_recvmsg(), we'll make a call to skb_copy_and_csum_datagram_msg()
to checksum the packet data and add it in the garbage skb->csum value
to perform our final validation check.

Since the value we're validating is not the proper checksum, it's possible
that the folded value could come out to 0, causing us not to drop the
packet. Instead, we believe that the packet was checksummed incorrectly
by hardware since skb->ip_summed is still CHECKSUM_COMPLETE, and we attempt
to warn the user with netdev_rx_csum_fault(skb->dev);

Unfortunately, since this is the UDP path, skb->dev has been overwritten
by skb->dev_scratch and is no longer a valid pointer, so we end up
reading invalid memory.

This patch addresses this problem in two ways:
	1) Do not use the dev pointer when calling netdev_rx_csum_fault()
	   from skb_copy_and_csum_datagram_msg(). Since this gets called
	   from the UDP path where skb->dev has been overwritten, we have
	   no way of knowing if the pointer is still valid. Also for the
	   sake of consistency with the other uses of
	   netdev_rx_csum_fault(), don't attempt to call it if the
	   packet was checksummed by software.

	2) Add better CHECKSUM_COMPLETE handling to udp4/6_csum_init().
	   If we receive a packet that's CHECKSUM_COMPLETE that fails
	   verification (i.e. skb->csum_valid == 0), check who performed
	   the calculation. It's possible that the checksum was done in
	   software by the network stack earlier (such as Netfilter's
	   CONNTRACK module), and if that says the checksum is bad,
	   we can drop the packet immediately instead of waiting until
	   we try and copy it to userspace. Otherwise, we need to
	   mark the SKB as CHECKSUM_NONE, since the skb->csum field
	   no longer contains the full packet checksum after the
	   call to __skb_checksum_validate_complete().

Fixes: e6afc8ace6 ("udp: remove headers from UDP packets before queueing")
Fixes: c84d949057 ("udp: copy skb->truesize in the first cache line")
Cc: Sam Kumar <samanthakumar@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Sean Tranchetti <stranche@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-24 14:18:16 -07:00
David Ahern
ae677bbb44 net: Don't return invalid table id error when dumping all families
When doing a route dump across all address families, do not error out
if the table does not exist. This allows a route dump for AF_UNSPEC
with a table id that may only exist for some of the families.

Do return the table does not exist error if dumping routes for a
specific family and the table does not exist.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-24 14:06:25 -07:00
David Ahern
242afaa696 net/ipv6: Put target net when address dump fails due to bad attributes
If tgt_net is set based on IFA_TARGET_NETNSID attribute in the dump
request, make sure all error paths call put_net.

Fixes: 6371a71f3a ("net/ipv6: Add support for dumping addresses for a specific device")
Fixes: ed6eff1179 ("net/ipv6: Update inet6_dump_addr for strict data checking")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-24 14:06:25 -07:00
David Ahern
6371a71f3a net/ipv6: Add support for dumping addresses for a specific device
If an RTM_GETADDR dump request has ifa_index set in the ifaddrmsg
header, then return only the addresses for that device.

Since inet6_dump_addr is reused for multicast and anycast addresses,
this adds support for device specfic dumps of RTM_GETMULTICAST and
RTM_GETANYCAST as well.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-22 19:33:29 -07:00
David Ahern
fe884c2be0 net/ipv6: Remove ip_idx arg to in6_dump_addrs
ip_idx is always 0 going into in6_dump_addrs; it is passed as a pointer
to save the last good index into cb. Since cb is already argument to
in6_dump_addrs, just save the value there.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-22 19:33:29 -07:00
David S. Miller
21ea1d36f6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
David Ahern's dump indexing bug fix in 'net' overlapped the
change of the function signature of inet6_fill_ifaddr() in
'net-next'.  Trivially resolved.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-21 11:54:28 -07:00
David Ahern
4ba4c566ba net/ipv6: Fix index counter for unicast addresses in in6_dump_addrs
The loop wants to skip previously dumped addresses, so loops until
current index >= saved index. If the message fills it wants to save
the index for the next address to dump - ie., the one that did not
fit in the current message.

Currently, it is incrementing the index counter before comparing to the
saved index, and then the saved index is off by 1 - it assumes the
current address is going to fit in the message.

Change the index handling to increment only after a succesful dump.

Fixes: 502a2ffd73 ("ipv6: convert idev_list to list macros")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-20 15:43:14 -07:00
David S. Miller
2e2d6f0342 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
net/sched/cls_api.c has overlapping changes to a call to
nlmsg_parse(), one (from 'net') added rtm_tca_policy instead of NULL
to the 5th argument, and another (from 'net-next') added cb->extack
instead of NULL to the 6th argument.

net/ipv4/ipmr_base.c is a case of a bug fix in 'net' being done to
code which moved (to mr_table_dump)) in 'net-next'.  Thanks to David
Ahern for the heads up.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-19 11:03:06 -07:00
Stefano Brivio
d4d576f5ab ip6_tunnel: Fix encapsulation layout
Commit 058214a4d1 ("ip6_tun: Add infrastructure for doing
encapsulation") added the ip6_tnl_encap() call in ip6_tnl_xmit(), before
the call to ipv6_push_frag_opts() to append the IPv6 Tunnel Encapsulation
Limit option (option 4, RFC 2473, par. 5.1) to the outer IPv6 header.

As long as the option didn't actually end up in generated packets, this
wasn't an issue. Then commit 89a23c8b52 ("ip6_tunnel: Fix missing tunnel
encapsulation limit option") fixed sending of this option, and the
resulting layout, e.g. for FoU, is:

.-------------------.------------.----------.-------------------.----- - -
| Outer IPv6 Header | UDP header | Option 4 | Inner IPv6 Header | Payload
'-------------------'------------'----------'-------------------'----- - -

Needless to say, FoU and GUE (at least) won't work over IPv6. The option
is appended by default, and I couldn't find a way to disable it with the
current iproute2.

Turn this into a more reasonable:

.-------------------.----------.------------.-------------------.----- - -
| Outer IPv6 Header | Option 4 | UDP header | Inner IPv6 Header | Payload
'-------------------'----------'------------'-------------------'----- - -

With this, and with 84dad55951 ("udp6: fix encap return code for
resubmitting"), FoU and GUE work again over IPv6.

Fixes: 058214a4d1 ("ip6_tun: Add infrastructure for doing encapsulation")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-18 16:54:40 -07:00
David S. Miller
2ee653f644 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec
Steffen Klassert says:

====================
pull request (net): ipsec 2018-10-18

1) Free the xfrm interface gro_cells when deleting the
   interface, otherwise we leak it. From Li RongQing.

2) net/core/flow.c does not exist anymore, so remove it
   from the MAINTAINERS file.

3) Fix a slab-out-of-bounds in _decode_session6.
   From Alexei Starovoitov.

4) Fix RCU protection when policies inserted into
   thei bydst lists. From Florian Westphal.

Please pull or let me know if there are problems.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-18 09:55:08 -07:00
Paolo Abeni
84dad55951 udp6: fix encap return code for resubmitting
The commit eb63f2964d ("udp6: add missing checks on edumux packet
processing") used the same return code convention of the ipv4 counterpart,
but ipv6 uses the opposite one: positive values means resubmit.

This change addresses the issue, using positive return value for
resubmitting. Also update the related comment, which was broken, too.

Fixes: eb63f2964d ("udp6: add missing checks on edumux packet processing")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-17 22:26:53 -07:00
David Ahern
08e814c9e8 net/ipv6: Bail early if user only wants cloned entries
Similar to IPv4, IPv6 fib no longer contains cloned routes. If a user
requests a route dump for only cloned entries, no sense walking the FIB
and returning everything.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-16 00:14:07 -07:00
David Ahern
effe679266 net: Enable kernel side filtering of route dumps
Update parsing of route dump request to enable kernel side filtering.
Allow filtering results by protocol (e.g., which routing daemon installed
the route), route type (e.g., unicast), table id and nexthop device. These
amount to the low hanging fruit, yet a huge improvement, for dumping
routes.

ip_valid_fib_dump_req is called with RTNL held, so __dev_get_by_index can
be used to look up the device index without taking a reference. From
there filter->dev is only used during dump loops with the lock still held.

Set NLM_F_DUMP_FILTERED in the answer_flags so the user knows the results
have been filtered should no entries be returned.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-16 00:14:07 -07:00
David Ahern
cb167893f4 net: Plumb support for filtering ipv4 and ipv6 multicast route dumps
Implement kernel side filtering of routes by egress device index and
table id. If the table id is given in the filter, lookup table and
call mr_table_dump directly for it.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-16 00:13:39 -07:00
David Ahern
13e38901d4 net/ipv6: Plumb support for filtering route dumps
Implement kernel side filtering of routes by table id, egress device
index, protocol, and route type. If the table id is given in the filter,
lookup the table and call fib6_dump_table directly for it.

Move the existing route flags check for prefix only routes to the new
filter.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-16 00:13:12 -07:00
David Ahern
4724676d55 net: Add struct for fib dump filter
Add struct fib_dump_filter for options on limiting which routes are
returned in a dump request. The current list is table id, protocol,
route type, rtm_flags and nexthop device index. struct net is needed
to lookup the net_device from the index.

Declare the filter for each route dump handler and plumb the new
arguments from dump handlers to ip_valid_fib_dump_req.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-16 00:13:12 -07:00
David S. Miller
e85679511e Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2018-10-16

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) Convert BPF sockmap and kTLS to both use a new sk_msg API and enable
   sk_msg BPF integration for the latter, from Daniel and John.

2) Enable BPF syscall side to indicate for maps that they do not support
   a map lookup operation as opposed to just missing key, from Prashant.

3) Add bpftool map create command which after map creation pins the
   map into bpf fs for further processing, from Jakub.

4) Add bpftool support for attaching programs to maps allowing sock_map
   and sock_hash to be used from bpftool, from John.

5) Improve syscall BPF map update/delete path for map-in-map types to
   wait a RCU grace period for pending references to complete, from Daniel.

6) Couple of follow-up fixes for the BPF socket lookup to get it
   enabled also when IPv6 is compiled as a module, from Joe.

7) Fix a generic-XDP bug to handle the case when the Ethernet header
   was mangled and thus update skb's protocol and data, from Jesper.

8) Add a missing BTF header length check between header copies from
   user space, from Wenwen.

9) Minor fixups in libbpf to use __u32 instead u32 types and include
   proper perf_event.h uapi header instead of perf internal one, from Yonghong.

10) Allow to pass user-defined flags through EXTRA_CFLAGS and EXTRA_LDFLAGS
    to bpftool's build, from Jiri.

11) BPF kselftest tweaks to add LWTUNNEL to config fragment and to install
    with_addr.sh script from flow dissector selftest, from Anders.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-15 23:21:07 -07:00
Eric Dumazet
dc012f3628 ipv6: mcast: fix a use-after-free in inet6_mc_check
syzbot found a use-after-free in inet6_mc_check [1]

The problem here is that inet6_mc_check() uses rcu
and read_lock(&iml->sflock)

So the fact that ip6_mc_leave_src() is called under RTNL
and the socket lock does not help us, we need to acquire
iml->sflock in write mode.

In the future, we should convert all this stuff to RCU.

[1]
BUG: KASAN: use-after-free in ipv6_addr_equal include/net/ipv6.h:521 [inline]
BUG: KASAN: use-after-free in inet6_mc_check+0xae7/0xb40 net/ipv6/mcast.c:649
Read of size 8 at addr ffff8801ce7f2510 by task syz-executor0/22432

CPU: 1 PID: 22432 Comm: syz-executor0 Not tainted 4.19.0-rc7+ #280
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+0x1c4/0x2b4 lib/dump_stack.c:113
 print_address_description.cold.8+0x9/0x1ff mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.9+0x242/0x309 mm/kasan/report.c:412
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
 ipv6_addr_equal include/net/ipv6.h:521 [inline]
 inet6_mc_check+0xae7/0xb40 net/ipv6/mcast.c:649
 __raw_v6_lookup+0x320/0x3f0 net/ipv6/raw.c:98
 ipv6_raw_deliver net/ipv6/raw.c:183 [inline]
 raw6_local_deliver+0x3d3/0xcb0 net/ipv6/raw.c:240
 ip6_input_finish+0x467/0x1aa0 net/ipv6/ip6_input.c:345
 NF_HOOK include/linux/netfilter.h:289 [inline]
 ip6_input+0xe9/0x600 net/ipv6/ip6_input.c:426
 ip6_mc_input+0x48a/0xd20 net/ipv6/ip6_input.c:503
 dst_input include/net/dst.h:450 [inline]
 ip6_rcv_finish+0x17a/0x330 net/ipv6/ip6_input.c:76
 NF_HOOK include/linux/netfilter.h:289 [inline]
 ipv6_rcv+0x120/0x640 net/ipv6/ip6_input.c:271
 __netif_receive_skb_one_core+0x14d/0x200 net/core/dev.c:4913
 __netif_receive_skb+0x2c/0x1e0 net/core/dev.c:5023
 netif_receive_skb_internal+0x12c/0x620 net/core/dev.c:5126
 napi_frags_finish net/core/dev.c:5664 [inline]
 napi_gro_frags+0x75a/0xc90 net/core/dev.c:5737
 tun_get_user+0x3189/0x4250 drivers/net/tun.c:1923
 tun_chr_write_iter+0xb9/0x154 drivers/net/tun.c:1968
 call_write_iter include/linux/fs.h:1808 [inline]
 do_iter_readv_writev+0x8b0/0xa80 fs/read_write.c:680
 do_iter_write+0x185/0x5f0 fs/read_write.c:959
 vfs_writev+0x1f1/0x360 fs/read_write.c:1004
 do_writev+0x11a/0x310 fs/read_write.c:1039
 __do_sys_writev fs/read_write.c:1112 [inline]
 __se_sys_writev fs/read_write.c:1109 [inline]
 __x64_sys_writev+0x75/0xb0 fs/read_write.c:1109
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457421
Code: 75 14 b8 14 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 34 b5 fb ff c3 48 83 ec 08 e8 1a 2d 00 00 48 89 04 24 b8 14 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 63 2d 00 00 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:00007f2d30ecaba0 EFLAGS: 00000293 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 000000000000003e RCX: 0000000000457421
RDX: 0000000000000001 RSI: 00007f2d30ecabf0 RDI: 00000000000000f0
RBP: 0000000020000500 R08: 00000000000000f0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 00007f2d30ecb6d4
R13: 00000000004c4890 R14: 00000000004d7b90 R15: 00000000ffffffff

Allocated by task 22437:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553
 __do_kmalloc mm/slab.c:3718 [inline]
 __kmalloc+0x14e/0x760 mm/slab.c:3727
 kmalloc include/linux/slab.h:518 [inline]
 sock_kmalloc+0x15a/0x1f0 net/core/sock.c:1983
 ip6_mc_source+0x14dd/0x1960 net/ipv6/mcast.c:427
 do_ipv6_setsockopt.isra.9+0x3afb/0x45d0 net/ipv6/ipv6_sockglue.c:743
 ipv6_setsockopt+0xbd/0x170 net/ipv6/ipv6_sockglue.c:933
 rawv6_setsockopt+0x59/0x140 net/ipv6/raw.c:1069
 sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:3038
 __sys_setsockopt+0x1ba/0x3c0 net/socket.c:1902
 __do_sys_setsockopt net/socket.c:1913 [inline]
 __se_sys_setsockopt net/socket.c:1910 [inline]
 __x64_sys_setsockopt+0xbe/0x150 net/socket.c:1910
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 22430:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3498 [inline]
 kfree+0xcf/0x230 mm/slab.c:3813
 __sock_kfree_s net/core/sock.c:2004 [inline]
 sock_kfree_s+0x29/0x60 net/core/sock.c:2010
 ip6_mc_leave_src+0x11a/0x1d0 net/ipv6/mcast.c:2448
 __ipv6_sock_mc_close+0x20b/0x4e0 net/ipv6/mcast.c:310
 ipv6_sock_mc_close+0x158/0x1d0 net/ipv6/mcast.c:328
 inet6_release+0x40/0x70 net/ipv6/af_inet6.c:452
 __sock_release+0xd7/0x250 net/socket.c:579
 sock_close+0x19/0x20 net/socket.c:1141
 __fput+0x385/0xa30 fs/file_table.c:278
 ____fput+0x15/0x20 fs/file_table.c:309
 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:193 [inline]
 exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8801ce7f2500
 which belongs to the cache kmalloc-192 of size 192
The buggy address is located 16 bytes inside of
 192-byte region [ffff8801ce7f2500, ffff8801ce7f25c0)
The buggy address belongs to the page:
page:ffffea000739fc80 count:1 mapcount:0 mapping:ffff8801da800040 index:0x0
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffffea0006f6e548 ffffea000737b948 ffff8801da800040
raw: 0000000000000000 ffff8801ce7f2000 0000000100000010 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801ce7f2400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8801ce7f2480: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff8801ce7f2500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff8801ce7f2580: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8801ce7f2600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-15 22:38:55 -07:00
Sabrina Dubroca
f547fac624 ipv6: rate-limit probes for neighbourless routes
When commit 270972554c ("[IPV6]: ROUTE: Add Router Reachability
Probing (RFC4191).") introduced router probing, the rt6_probe() function
required that a neighbour entry existed. This neighbour entry is used to
record the timestamp of the last probe via the ->updated field.

Later, commit 2152caea71 ("ipv6: Do not depend on rt->n in rt6_probe().")
removed the requirement for a neighbour entry. Neighbourless routes skip
the interval check and are not rate-limited.

This patch adds rate-limiting for neighbourless routes, by recording the
timestamp of the last probe in the fib6_info itself.

Fixes: 2152caea71 ("ipv6: Do not depend on rt->n in rt6_probe().")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-15 22:18:27 -07:00
Joe Stringer
8a615c6b03 bpf: Allow sk_lookup with IPv6 module
This is a more complete fix than d71019b54b ("net: core: Fix build
with CONFIG_IPV6=m"), so that IPv6 sockets may be looked up if the IPv6
module is loaded (not just if it's compiled in).

Signed-off-by: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-10-15 16:08:39 -07:00
David S. Miller
d864991b22 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts were easy to resolve using immediate context mostly,
except the cls_u32.c one where I simply too the entire HEAD
chunk.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-12 21:38:46 -07:00
David Ahern
859bd2ef1f net: Evict neighbor entries on carrier down
When a link's carrier goes down it could be a sign of the port changing
networks. If the new network has overlapping addresses with the old one,
then the kernel will continue trying to use neighbor entries established
based on the old network until the entries finally age out - meaning a
potentially long delay with communications not working.

This patch evicts neighbor entries on carrier down with the exception of
those marked permanent. Permanent entries are managed by userspace (either
an admin or a routing daemon such as FRR).

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-12 09:47:39 -07:00
David Ahern
7c6bb7d2fa net/ipv6: Add knob to skip DELROUTE message on device down
Another difference between IPv4 and IPv6 is the generation of RTM_DELROUTE
notifications when a device is taken down (admin down) or deleted. IPv4
does not generate a message for routes evicted by the down or delete;
IPv6 does. A NOS at scale really needs to avoid these messages and have
IPv4 and IPv6 behave similarly, relying on userspace to handle link
notifications and evict the routes.

At this point existing user behavior needs to be preserved. Since
notifications are a global action (not per app) the only way to preserve
existing behavior and allow the messages to be skipped is to add a new
sysctl (net/ipv6/route/skip_notify_on_dev_down) which can be set to
disable the notificatioons.

IPv6 route code already supports the option to skip the message (it is
used for multipath routes for example). Besides the new sysctl we need
to pass the skip_notify setting through the generic fib6_clean and
fib6_walk functions to fib6_clean_node and to set skip_notify on calls
to __ip_del_rt for the addrconf_ifdown path.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-12 09:47:02 -07:00
Alexei Starovoitov
9f7e43da6a net/xfrm: fix out-of-bounds packet access
BUG: KASAN: slab-out-of-bounds in _decode_session6+0x1331/0x14e0
net/ipv6/xfrm6_policy.c:161
Read of size 1 at addr ffff8801d882eec7 by task syz-executor1/6667
Call Trace:
  __dump_stack lib/dump_stack.c:77 [inline]
  dump_stack+0x1c9/0x2b4 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+0x242/0x30d mm/kasan/report.c:412
  __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430
  _decode_session6+0x1331/0x14e0 net/ipv6/xfrm6_policy.c:161
  __xfrm_decode_session+0x71/0x140 net/xfrm/xfrm_policy.c:2299
  xfrm_decode_session include/net/xfrm.h:1232 [inline]
  vti6_tnl_xmit+0x3c3/0x1bc1 net/ipv6/ip6_vti.c:542
  __netdev_start_xmit include/linux/netdevice.h:4313 [inline]
  netdev_start_xmit include/linux/netdevice.h:4322 [inline]
  xmit_one net/core/dev.c:3217 [inline]
  dev_hard_start_xmit+0x272/0xc10 net/core/dev.c:3233
  __dev_queue_xmit+0x2ab2/0x3870 net/core/dev.c:3803
  dev_queue_xmit+0x17/0x20 net/core/dev.c:3836

Reported-by: syzbot+acffccec848dc13fe459@syzkaller.appspotmail.com
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2018-10-11 13:24:46 +02:00
Mike Rapoport
7abab7b9b4 net/ipv6: stop leaking percpu memory in fib6 info
The fib6_info_alloc() function allocates percpu memory to hold per CPU
pointers to rt6_info, but this memory is never freed. Fix it.

Fixes: a64efe142f ("net/ipv6: introduce fib6_info struct and helpers")
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-10 22:42:54 -07:00
David Ahern
ed792e28c4 net/ipv6: Make ipv6_route_table_template static
ipv6_route_table_template is exported but there are no users outside
of route.c. Make it static.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-10 22:25:10 -07:00
David S. Miller
9000a457a0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for your net-next tree:

1) Support for matching on ipsec policy already set in the route, from
   Florian Westphal.

2) Split set destruction into deactivate and destroy phase to make it
   fit better into the transaction infrastructure, also from Florian.
   This includes a patch to warn on imbalance when setting the new
   activate and deactivate interfaces.

3) Release transaction list from the workqueue to remove expensive
   synchronize_rcu() from configuration plane path. This speeds up
   configuration plane quite a bit. From Florian Westphal.

4) Add new xfrm/ipsec extension, this new extension allows you to match
   for ipsec tunnel keys such as source and destination address, spi and
   reqid. From Máté Eckl and Florian Westphal.

5) Add secmark support, this includes connsecmark too, patches
   from Christian Gottsche.

6) Allow to specify remaining bytes in xt_quota, from Chenbo Feng.
   One follow up patch to calm a clang warning for this one, from
   Nathan Chancellor.

7) Flush conntrack entries based on layer 3 family, from Kristian Evensen.

8) New revision for cgroups2 to shrink the path field.

9) Get rid of obsolete need_conntrack(), as a result from recent
   demodularization works.

10) Use WARN_ON instead of BUG_ON, from Florian Westphal.

11) Unused exported symbol in nf_nat_ipv4_fn(), from Florian.

12) Remove superfluous check for timeout netlink parser and dump
    functions in layer 4 conntrack helpers.

13) Unnecessary redundant rcu read side locks in NAT redirect,
    from Taehee Yoo.

14) Pass nf_hook_state structure to error handlers, patch from
    Florian Westphal.

15) Remove ->new() interface from layer 4 protocol trackers. Place
    them in the ->packet() interface. From Florian.

16) Place conntrack ->error() handling in the ->packet() interface.
    Patches from Florian Westphal.

17) Remove unused parameter in the pernet initialization path,
    also from Florian.

18) Remove additional parameter to specify layer 3 protocol when
    looking up for protocol tracker. From Florian.

19) Shrink array of layer 4 protocol trackers, from Florian.

20) Check for linear skb only once from the ALG NAT mangling
    codebase, from Taehee Yoo.

21) Use rhashtable_walk_enter() instead of deprecated
    rhashtable_walk_init(), also from Taehee.

22) No need to flush all conntracks when only one single address
    is gone, from Tan Hu.

23) Remove redundant check for NAT flags in flowtable code, from
    Taehee Yoo.

24) Use rhashtable_lookup() instead of rhashtable_lookup_fast()
    from netfilter codebase, since rcu read lock side is already
    assumed in this path.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-08 21:28:55 -07:00
David Ahern
addd383f5a net: Update netconf dump handlers for strict data checking
Update inet_netconf_dump_devconf, inet6_netconf_dump_devconf, and
mpls_netconf_dump_devconf for strict data checking. If the flag is set,
the dump request is expected to have an netconfmsg struct as the header.
The struct only has the family member and no attributes can be appended.

Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: Christian Brauner <christian@brauner.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-08 10:39:05 -07:00
David Ahern
f2ae64bb6b net/ipv6: Update ip6addrlbl_dump for strict data checking
Update ip6addrlbl_dump for strict data checking. If the flag is set,
the dump request is expected to have an ifaddrlblmsg struct as the
header. All elements of the struct are expected to be 0 and no
attributes can be appended.

Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: Christian Brauner <christian@brauner.io>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-08 10:39:05 -07:00
David Ahern
e8ba330ac0 rtnetlink: Update fib dumps for strict data checking
Add helper to check netlink message for route dumps. If the strict flag
is set the dump request is expected to have an rtmsg struct as the header.
All elements of the struct are expected to be 0 with the exception of
rtm_flags (which is used by both ipv4 and ipv6 dumps) and no attributes
can be appended. rtm_flags can only have RTM_F_CLONED and RTM_F_PREFIX
set.

Update inet_dump_fib, inet6_dump_fib, mpls_dump_routes, ipmr_rtm_dumproute,
and ip6mr_rtm_dumproute to call this helper if strict data checking is
enabled.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-08 10:39:05 -07:00