Commit Graph

5826 Commits

Author SHA1 Message Date
Mathieu Xhonneux
3a16f3bcb2 ipv6: sr: fix memory OOB access in seg6_do_srh_encap/inline
[ Upstream commit bbb40a0b75 ]

seg6_do_srh_encap and seg6_do_srh_inline can possibly do an
out-of-bounds access when adding the SRH to the packet. This no longer
happen when expanding the skb not only by the size of the SRH (+
outer IPv6 header), but also by skb->mac_len.

[   53.793056] BUG: KASAN: use-after-free in seg6_do_srh_encap+0x284/0x620
[   53.794564] Write of size 14 at addr ffff88011975ecfa by task ping/674

[   53.796665] CPU: 0 PID: 674 Comm: ping Not tainted 4.17.0-rc3-ARCH+ #90
[   53.796670] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS 1.11.0-20171110_100015-anatol 04/01/2014
[   53.796673] Call Trace:
[   53.796679]  <IRQ>
[   53.796689]  dump_stack+0x71/0xab
[   53.796700]  print_address_description+0x6a/0x270
[   53.796707]  kasan_report+0x258/0x380
[   53.796715]  ? seg6_do_srh_encap+0x284/0x620
[   53.796722]  memmove+0x34/0x50
[   53.796730]  seg6_do_srh_encap+0x284/0x620
[   53.796741]  ? seg6_do_srh+0x29b/0x360
[   53.796747]  seg6_do_srh+0x29b/0x360
[   53.796756]  seg6_input+0x2e/0x2e0
[   53.796765]  lwtunnel_input+0x93/0xd0
[   53.796774]  ipv6_rcv+0x690/0x920
[   53.796783]  ? ip6_input+0x170/0x170
[   53.796791]  ? eth_gro_receive+0x2d0/0x2d0
[   53.796800]  ? ip6_input+0x170/0x170
[   53.796809]  __netif_receive_skb_core+0xcc0/0x13f0
[   53.796820]  ? netdev_info+0x110/0x110
[   53.796827]  ? napi_complete_done+0xb6/0x170
[   53.796834]  ? e1000_clean+0x6da/0xf70
[   53.796845]  ? process_backlog+0x129/0x2a0
[   53.796853]  process_backlog+0x129/0x2a0
[   53.796862]  net_rx_action+0x211/0x5c0
[   53.796870]  ? napi_complete_done+0x170/0x170
[   53.796887]  ? run_rebalance_domains+0x11f/0x150
[   53.796891]  __do_softirq+0x10e/0x39e
[   53.796894]  do_softirq_own_stack+0x2a/0x40
[   53.796895]  </IRQ>
[   53.796898]  do_softirq.part.16+0x54/0x60
[   53.796900]  __local_bh_enable_ip+0x5b/0x60
[   53.796903]  ip6_finish_output2+0x416/0x9f0
[   53.796906]  ? ip6_dst_lookup_flow+0x110/0x110
[   53.796909]  ? ip6_sk_dst_lookup_flow+0x390/0x390
[   53.796911]  ? __rcu_read_unlock+0x66/0x80
[   53.796913]  ? ip6_mtu+0x44/0xf0
[   53.796916]  ? ip6_output+0xfc/0x220
[   53.796918]  ip6_output+0xfc/0x220
[   53.796921]  ? ip6_finish_output+0x2b0/0x2b0
[   53.796923]  ? memcpy+0x34/0x50
[   53.796926]  ip6_send_skb+0x43/0xc0
[   53.796929]  rawv6_sendmsg+0x1216/0x1530
[   53.796932]  ? __orc_find+0x6b/0xc0
[   53.796934]  ? rawv6_rcv_skb+0x160/0x160
[   53.796937]  ? __rcu_read_unlock+0x66/0x80
[   53.796939]  ? __rcu_read_unlock+0x66/0x80
[   53.796942]  ? is_bpf_text_address+0x1e/0x30
[   53.796944]  ? kernel_text_address+0xec/0x100
[   53.796946]  ? __kernel_text_address+0xe/0x30
[   53.796948]  ? unwind_get_return_address+0x2f/0x50
[   53.796950]  ? __save_stack_trace+0x92/0x100
[   53.796954]  ? save_stack+0x89/0xb0
[   53.796956]  ? kasan_kmalloc+0xa0/0xd0
[   53.796958]  ? kmem_cache_alloc+0xd2/0x1f0
[   53.796961]  ? prepare_creds+0x23/0x160
[   53.796963]  ? __x64_sys_capset+0x252/0x3e0
[   53.796966]  ? do_syscall_64+0x69/0x160
[   53.796968]  ? entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   53.796971]  ? __alloc_pages_nodemask+0x170/0x380
[   53.796973]  ? __alloc_pages_slowpath+0x12c0/0x12c0
[   53.796977]  ? tty_vhangup+0x20/0x20
[   53.796979]  ? policy_nodemask+0x1a/0x90
[   53.796982]  ? __mod_node_page_state+0x8d/0xa0
[   53.796986]  ? __check_object_size+0xe7/0x240
[   53.796989]  ? __sys_sendto+0x229/0x290
[   53.796991]  ? rawv6_rcv_skb+0x160/0x160
[   53.796993]  __sys_sendto+0x229/0x290
[   53.796996]  ? __ia32_sys_getpeername+0x50/0x50
[   53.796999]  ? commit_creds+0x2de/0x520
[   53.797002]  ? security_capset+0x57/0x70
[   53.797004]  ? __x64_sys_capset+0x29f/0x3e0
[   53.797007]  ? __x64_sys_rt_sigsuspend+0xe0/0xe0
[   53.797011]  ? __do_page_fault+0x664/0x770
[   53.797014]  __x64_sys_sendto+0x74/0x90
[   53.797017]  do_syscall_64+0x69/0x160
[   53.797019]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   53.797022] RIP: 0033:0x7f43b7a6714a
[   53.797023] RSP: 002b:00007ffd891bd368 EFLAGS: 00000246 ORIG_RAX:
000000000000002c
[   53.797026] RAX: ffffffffffffffda RBX: 00000000006129c0 RCX: 00007f43b7a6714a
[   53.797028] RDX: 0000000000000040 RSI: 00000000006129c0 RDI: 0000000000000004
[   53.797029] RBP: 00007ffd891be640 R08: 0000000000610940 R09: 000000000000001c
[   53.797030] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000040
[   53.797032] R13: 000000000060e6a0 R14: 0000000000008004 R15: 000000000040b661

[   53.797171] Allocated by task 642:
[   53.797460]  kasan_kmalloc+0xa0/0xd0
[   53.797463]  kmem_cache_alloc+0xd2/0x1f0
[   53.797465]  getname_flags+0x40/0x210
[   53.797467]  user_path_at_empty+0x1d/0x40
[   53.797469]  do_faccessat+0x12a/0x320
[   53.797471]  do_syscall_64+0x69/0x160
[   53.797473]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

[   53.797607] Freed by task 642:
[   53.797869]  __kasan_slab_free+0x130/0x180
[   53.797871]  kmem_cache_free+0xa8/0x230
[   53.797872]  filename_lookup+0x15b/0x230
[   53.797874]  do_faccessat+0x12a/0x320
[   53.797876]  do_syscall_64+0x69/0x160
[   53.797878]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

[   53.798014] The buggy address belongs to the object at ffff88011975e600
                which belongs to the cache names_cache of size 4096
[   53.799043] The buggy address is located 1786 bytes inside of
                4096-byte region [ffff88011975e600, ffff88011975f600)
[   53.800013] The buggy address belongs to the page:
[   53.800414] page:ffffea000465d600 count:1 mapcount:0
mapping:0000000000000000 index:0x0 compound_mapcount: 0
[   53.801259] flags: 0x17fff0000008100(slab|head)
[   53.801640] raw: 017fff0000008100 0000000000000000 0000000000000000
0000000100070007
[   53.803147] raw: dead000000000100 dead000000000200 ffff88011b185a40
0000000000000000
[   53.803787] page dumped because: kasan: bad access detected

[   53.804384] Memory state around the buggy address:
[   53.804788]  ffff88011975eb80: fb fb fb fb fb fb fb fb fb fb fb fb
fb fb fb fb
[   53.805384]  ffff88011975ec00: fb fb fb fb fb fb fb fb fb fb fb fb
fb fb fb fb
[   53.805979] >ffff88011975ec80: fb fb fb fb fb fb fb fb fb fb fb fb
fb fb fb fb
[   53.806577]                                                                 ^
[   53.807165]  ffff88011975ed00: fb fb fb fb fb fb fb fb fb fb fb fb
fb fb fb fb
[   53.807762]  ffff88011975ed80: fb fb fb fb fb fb fb fb fb fb fb fb
fb fb fb fb
[   53.808356] ==================================================================
[   53.808949] Disabling lock debugging due to kernel taint

Fixes: 6c8702c60b ("ipv6: sr: add support for SRH encapsulation and injection with lwtunnels")
Signed-off-by: David Lebrun <dlebrun@google.com>
Signed-off-by: Mathieu Xhonneux <m.xhonneux@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-11 22:48:17 +02:00
Stephen Suryaputra
d15680f653 vrf: check the original netdevice for generating redirect
[ Upstream commit 2f17becfbe ]

Use the right device to determine if redirect should be sent especially
when using vrf. Same as well as when sending the redirect.

Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-11 22:48:17 +02:00
Michal Kubecek
f82695ccb2 ipv6: omit traffic class when calculating flow hash
[ Upstream commit fa1be7e01e ]

Some of the code paths calculating flow hash for IPv6 use flowlabel member
of struct flowi6 which, despite its name, encodes both flow label and
traffic class. If traffic class changes within a TCP connection (as e.g.
ssh does), ECMP route can switch between path. It's also inconsistent with
other code paths where ip6_flowlabel() (returning only flow label) is used
to feed the key.

Use only flow label everywhere, including one place where hash key is set
using ip6_flowinfo().

Fixes: 51ebd31815 ("ipv6: add support of equal cost multipath (ECMP)")
Fixes: f70ea018da ("net: Add functions to get skb->hash based on flow structures")
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-11 22:48:15 +02:00
Nicolas Dichtel
af9eca7e4e ip6_tunnel: remove magic mtu value 0xFFF8
[ Upstream commit f7ff1fde94 ]

I don't know where this value comes from (probably a copy and paste and
paste and paste ...).
Let's use standard values which are a bit greater.

Link: https://git.kernel.org/pub/scm/linux/kernel/git/davem/netdev-vger-cvs.git/commit/?id=e5afd356a411a
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-11 22:48:14 +02:00
Sabrina Dubroca
6811f3a16b ip6mr: only set ip6mr_table from setsockopt when ip6mr_new_table succeeds
[ Upstream commit 848235edb5 ]

Currently, raw6_sk(sk)->ip6mr_table is set unconditionally during
ip6_mroute_setsockopt(MRT6_TABLE). A subsequent attempt at the same
setsockopt will fail with -ENOENT, since we haven't actually created
that table.

A similar fix for ipv4 was included in commit 5e1859fbcc ("ipv4: ipmr:
various fixes and cleanups").

Fixes: d1db275dd3 ("ipv6: ip6mr: support multiple tables")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-11 22:48:14 +02:00
Jason A. Donenfeld
b4b1adf2e6 netfilter: nf_flow_table: attach dst to skbs
commit 2a79fd3908 upstream.

Some drivers, such as vxlan and wireguard, use the skb's dst in order to
determine things like PMTU. They therefore loose functionality when flow
offloading is enabled. So, we ensure the skb has it before xmit'ing it
in the offloading path.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-11 22:48:14 +02:00
William Tu
65b249d247 net: ip6_gre: fix tunnel metadata device sharing.
[ Upstream commit b80d0b93b9 ]

Currently ip6gre and ip6erspan share single metadata mode device,
using 'collect_md_tun'.  Thus, when doing:
  ip link add dev ip6gre11 type ip6gretap external
  ip link add dev ip6erspan12 type ip6erspan external
  RTNETLINK answers: File exists
simply fails due to the 2nd tries to create the same collect_md_tun.

The patch fixes it by adding a separate collect md tunnel device
for the ip6erspan, 'collect_md_tun_erspan'.  As a result, a couple
of places need to refactor/split up in order to distinguish ip6gre
and ip6erspan.

First, move the collect_md check at ip6gre_tunnel_{unlink,link} and
create separate function {ip6gre,ip6ersapn}_tunnel_{link_md,unlink_md}.
Then before link/unlink, make sure the link_md/unlink_md is called.
Finally, a separate ndo_uninit is created for ip6erspan.  Tested it
using the samples/bpf/test_tunnel_bpf.sh.

Fixes: ef7baf5e08 ("ip6_gre: add ip6 erspan collect_md mode")
Signed-off-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-25 16:46:04 +02:00
Petr Machata
c6d7262835 net: ip6_gre: Fix ip6erspan hlen calculation
[ Upstream commit 2d665034f2 ]

Even though ip6erspan_tap_init() sets up hlen and tun_hlen according to
what ERSPAN needs, it goes ahead to call ip6gre_tnl_link_config() which
overwrites these settings with GRE-specific ones.

Similarly for changelink callbacks, which are handled by
ip6gre_changelink() calls ip6gre_tnl_change() calls
ip6gre_tnl_link_config() as well.

The difference ends up being 12 vs. 20 bytes, and this is generally not
a problem, because a 12-byte request likely ends up allocating more and
the extra 8 bytes are thus available. However correct it is not.

So replace the newlink and changelink callbacks with an ERSPAN-specific
ones, reusing the newly-introduced _common() functions.

Fixes: 5a963eb61b ("ip6_gre: Add ERSPAN native tunnel support")
Signed-off-by: Petr Machata <petrm@mellanox.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-25 16:46:03 +02:00
Petr Machata
bf5b0c11ca net: ip6_gre: Split up ip6gre_changelink()
[ Upstream commit c8632fc30b ]

Extract from ip6gre_changelink() a reusable function
ip6gre_changelink_common(). This will allow introduction of
ERSPAN-specific _changelink() function with not a lot of code
duplication.

Fixes: 5a963eb61b ("ip6_gre: Add ERSPAN native tunnel support")
Signed-off-by: Petr Machata <petrm@mellanox.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-25 16:46:03 +02:00
Petr Machata
20e6b7c7e4 net: ip6_gre: Split up ip6gre_newlink()
[ Upstream commit 7fa38a7c85 ]

Extract from ip6gre_newlink() a reusable function
ip6gre_newlink_common(). The ip6gre_tnl_link_config() call needs to be
made customizable for ERSPAN, thus reorder it with calls to
ip6_tnl_change_mtu() and dev_hold(), and extract the whole tail to the
caller, ip6gre_newlink(). Thus enable an ERSPAN-specific _newlink()
function without a lot of duplicity.

Fixes: 5a963eb61b ("ip6_gre: Add ERSPAN native tunnel support")
Signed-off-by: Petr Machata <petrm@mellanox.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-25 16:46:03 +02:00
Petr Machata
cbacae4901 net: ip6_gre: Split up ip6gre_tnl_change()
[ Upstream commit a6465350ef ]

Split a reusable function ip6gre_tnl_copy_tnl_parm() from
ip6gre_tnl_change(). This will allow ERSPAN-specific code to
reuse the common parts while customizing the behavior for ERSPAN.

Fixes: 5a963eb61b ("ip6_gre: Add ERSPAN native tunnel support")
Signed-off-by: Petr Machata <petrm@mellanox.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-25 16:46:03 +02:00
Petr Machata
6d1e3b8e7f net: ip6_gre: Split up ip6gre_tnl_link_config()
[ Upstream commit a483373ead ]

The function ip6gre_tnl_link_config() is used for setting up
configuration of both ip6gretap and ip6erspan tunnels. Split the
function into the common part and the route-lookup part. The latter then
takes the calculated header length as an argument. This split will allow
the patches down the line to sneak in a custom header length computation
for the ERSPAN tunnel.

Fixes: 5a963eb61b ("ip6_gre: Add ERSPAN native tunnel support")
Signed-off-by: Petr Machata <petrm@mellanox.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-25 16:46:03 +02:00
Petr Machata
003ad57484 net: ip6_gre: Fix headroom request in ip6erspan_tunnel_xmit()
[ Upstream commit 5691484df9 ]

dev->needed_headroom is not primed until ip6_tnl_xmit(), so it starts
out zero. Thus the call to skb_cow_head() fails to actually make sure
there's enough headroom to push the ERSPAN headers to. That can lead to
the panic cited below. (Reproducer below that).

Fix by requesting either needed_headroom if already primed, or just the
bare minimum needed for the header otherwise.

[  190.703567] kernel BUG at net/core/skbuff.c:104!
[  190.708384] invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
[  190.714007] Modules linked in: act_mirred cls_matchall ip6_gre ip6_tunnel tunnel6 gre sch_ingress vrf veth x86_pkg_temp_thermal mlx_platform nfsd e1000e leds_mlxcpld
[  190.728975] CPU: 1 PID: 959 Comm: kworker/1:2 Not tainted 4.17.0-rc4-net_master-custom-139 #10
[  190.737647] Hardware name: Mellanox Technologies Ltd. "MSN2410-CB2F"/"SA000874", BIOS 4.6.5 03/08/2016
[  190.747006] Workqueue: ipv6_addrconf addrconf_dad_work
[  190.752222] RIP: 0010:skb_panic+0xc3/0x100
[  190.756358] RSP: 0018:ffff8801d54072f0 EFLAGS: 00010282
[  190.761629] RAX: 0000000000000085 RBX: ffff8801c1a8ecc0 RCX: 0000000000000000
[  190.768830] RDX: 0000000000000085 RSI: dffffc0000000000 RDI: ffffed003aa80e54
[  190.776025] RBP: ffff8801bd1ec5a0 R08: ffffed003aabce19 R09: ffffed003aabce19
[  190.783226] R10: 0000000000000001 R11: ffffed003aabce18 R12: ffff8801bf695dbe
[  190.790418] R13: 0000000000000084 R14: 00000000000006c0 R15: ffff8801bf695dc8
[  190.797621] FS:  0000000000000000(0000) GS:ffff8801d5400000(0000) knlGS:0000000000000000
[  190.805786] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  190.811582] CR2: 000055fa929aced0 CR3: 0000000003228004 CR4: 00000000001606e0
[  190.818790] Call Trace:
[  190.821264]  <IRQ>
[  190.823314]  ? ip6erspan_tunnel_xmit+0x5e4/0x1982 [ip6_gre]
[  190.828940]  ? ip6erspan_tunnel_xmit+0x5e4/0x1982 [ip6_gre]
[  190.834562]  skb_push+0x78/0x90
[  190.837749]  ip6erspan_tunnel_xmit+0x5e4/0x1982 [ip6_gre]
[  190.843219]  ? ip6gre_tunnel_ioctl+0xd90/0xd90 [ip6_gre]
[  190.848577]  ? debug_check_no_locks_freed+0x210/0x210
[  190.853679]  ? debug_check_no_locks_freed+0x210/0x210
[  190.858783]  ? print_irqtrace_events+0x120/0x120
[  190.863451]  ? sched_clock_cpu+0x18/0x210
[  190.867496]  ? cyc2ns_read_end+0x10/0x10
[  190.871474]  ? skb_network_protocol+0x76/0x200
[  190.875977]  dev_hard_start_xmit+0x137/0x770
[  190.880317]  ? do_raw_spin_trylock+0x6d/0xa0
[  190.884624]  sch_direct_xmit+0x2ef/0x5d0
[  190.888589]  ? pfifo_fast_dequeue+0x3fa/0x670
[  190.892994]  ? pfifo_fast_change_tx_queue_len+0x810/0x810
[  190.898455]  ? __lock_is_held+0xa0/0x160
[  190.902422]  __qdisc_run+0x39e/0xfc0
[  190.906041]  ? _raw_spin_unlock+0x29/0x40
[  190.910090]  ? pfifo_fast_enqueue+0x24b/0x3e0
[  190.914501]  ? sch_direct_xmit+0x5d0/0x5d0
[  190.918658]  ? pfifo_fast_dequeue+0x670/0x670
[  190.923047]  ? __dev_queue_xmit+0x172/0x1770
[  190.927365]  ? preempt_count_sub+0xf/0xd0
[  190.931421]  __dev_queue_xmit+0x410/0x1770
[  190.935553]  ? ___slab_alloc+0x605/0x930
[  190.939524]  ? print_irqtrace_events+0x120/0x120
[  190.944186]  ? memcpy+0x34/0x50
[  190.947364]  ? netdev_pick_tx+0x1c0/0x1c0
[  190.951428]  ? __skb_clone+0x2fd/0x3d0
[  190.955218]  ? __copy_skb_header+0x270/0x270
[  190.959537]  ? rcu_read_lock_sched_held+0x93/0xa0
[  190.964282]  ? kmem_cache_alloc+0x344/0x4d0
[  190.968520]  ? cyc2ns_read_end+0x10/0x10
[  190.972495]  ? skb_clone+0x123/0x230
[  190.976112]  ? skb_split+0x820/0x820
[  190.979747]  ? tcf_mirred+0x554/0x930 [act_mirred]
[  190.984582]  tcf_mirred+0x554/0x930 [act_mirred]
[  190.989252]  ? tcf_mirred_act_wants_ingress.part.2+0x10/0x10 [act_mirred]
[  190.996109]  ? __lock_acquire+0x706/0x26e0
[  191.000239]  ? sched_clock_cpu+0x18/0x210
[  191.004294]  tcf_action_exec+0xcf/0x2a0
[  191.008179]  tcf_classify+0xfa/0x340
[  191.011794]  __netif_receive_skb_core+0x8e1/0x1c60
[  191.016630]  ? debug_check_no_locks_freed+0x210/0x210
[  191.021732]  ? nf_ingress+0x500/0x500
[  191.025458]  ? process_backlog+0x347/0x4b0
[  191.029619]  ? print_irqtrace_events+0x120/0x120
[  191.034302]  ? lock_acquire+0xd8/0x320
[  191.038089]  ? process_backlog+0x1b6/0x4b0
[  191.042246]  ? process_backlog+0xc2/0x4b0
[  191.046303]  process_backlog+0xc2/0x4b0
[  191.050189]  net_rx_action+0x5cc/0x980
[  191.053991]  ? napi_complete_done+0x2c0/0x2c0
[  191.058386]  ? mark_lock+0x13d/0xb40
[  191.062001]  ? clockevents_program_event+0x6b/0x1d0
[  191.066922]  ? print_irqtrace_events+0x120/0x120
[  191.071593]  ? __lock_is_held+0xa0/0x160
[  191.075566]  __do_softirq+0x1d4/0x9d2
[  191.079282]  ? ip6_finish_output2+0x524/0x1460
[  191.083771]  do_softirq_own_stack+0x2a/0x40
[  191.087994]  </IRQ>
[  191.090130]  do_softirq.part.13+0x38/0x40
[  191.094178]  __local_bh_enable_ip+0x135/0x190
[  191.098591]  ip6_finish_output2+0x54d/0x1460
[  191.102916]  ? ip6_forward_finish+0x2f0/0x2f0
[  191.107314]  ? ip6_mtu+0x3c/0x2c0
[  191.110674]  ? ip6_finish_output+0x2f8/0x650
[  191.114992]  ? ip6_output+0x12a/0x500
[  191.118696]  ip6_output+0x12a/0x500
[  191.122223]  ? ip6_route_dev_notify+0x5b0/0x5b0
[  191.126807]  ? ip6_finish_output+0x650/0x650
[  191.131120]  ? ip6_fragment+0x1a60/0x1a60
[  191.135182]  ? icmp6_dst_alloc+0x26e/0x470
[  191.139317]  mld_sendpack+0x672/0x830
[  191.143021]  ? igmp6_mcf_seq_next+0x2f0/0x2f0
[  191.147429]  ? __local_bh_enable_ip+0x77/0x190
[  191.151913]  ipv6_mc_dad_complete+0x47/0x90
[  191.156144]  addrconf_dad_completed+0x561/0x720
[  191.160731]  ? addrconf_rs_timer+0x3a0/0x3a0
[  191.165036]  ? mark_held_locks+0xc9/0x140
[  191.169095]  ? __local_bh_enable_ip+0x77/0x190
[  191.173570]  ? addrconf_dad_work+0x50d/0xa20
[  191.177886]  ? addrconf_dad_work+0x529/0xa20
[  191.182194]  addrconf_dad_work+0x529/0xa20
[  191.186342]  ? addrconf_dad_completed+0x720/0x720
[  191.191088]  ? __lock_is_held+0xa0/0x160
[  191.195059]  ? process_one_work+0x45d/0xe20
[  191.199302]  ? process_one_work+0x51e/0xe20
[  191.203531]  ? rcu_read_lock_sched_held+0x93/0xa0
[  191.208279]  process_one_work+0x51e/0xe20
[  191.212340]  ? pwq_dec_nr_in_flight+0x200/0x200
[  191.216912]  ? get_lock_stats+0x4b/0xf0
[  191.220788]  ? preempt_count_sub+0xf/0xd0
[  191.224844]  ? worker_thread+0x219/0x860
[  191.228823]  ? do_raw_spin_trylock+0x6d/0xa0
[  191.233142]  worker_thread+0xeb/0x860
[  191.236848]  ? process_one_work+0xe20/0xe20
[  191.241095]  kthread+0x206/0x300
[  191.244352]  ? process_one_work+0xe20/0xe20
[  191.248587]  ? kthread_stop+0x570/0x570
[  191.252459]  ret_from_fork+0x3a/0x50
[  191.256082] Code: 14 3e ff 8b 4b 78 55 4d 89 f9 41 56 41 55 48 c7 c7 a0 cf db 82 41 54 44 8b 44 24 2c 48 8b 54 24 30 48 8b 74 24 20 e8 16 94 13 ff <0f> 0b 48 c7 c7 60 8e 1f 85 48 83 c4 20 e8 55 ef a6 ff 89 74 24
[  191.275327] RIP: skb_panic+0xc3/0x100 RSP: ffff8801d54072f0
[  191.281024] ---[ end trace 7ea51094e099e006 ]---
[  191.285724] Kernel panic - not syncing: Fatal exception in interrupt
[  191.292168] Kernel Offset: disabled
[  191.295697] ---[ end Kernel panic - not syncing: Fatal exception in interrupt ]---

Reproducer:

	ip link add h1 type veth peer name swp1
	ip link add h3 type veth peer name swp3

	ip link set dev h1 up
	ip address add 192.0.2.1/28 dev h1

	ip link add dev vh3 type vrf table 20
	ip link set dev h3 master vh3
	ip link set dev vh3 up
	ip link set dev h3 up

	ip link set dev swp3 up
	ip address add dev swp3 2001:db8:2::1/64

	ip link set dev swp1 up
	tc qdisc add dev swp1 clsact

	ip link add name gt6 type ip6erspan \
		local 2001:db8:2::1 remote 2001:db8:2::2 oseq okey 123
	ip link set dev gt6 up

	sleep 1

	tc filter add dev swp1 ingress pref 1000 matchall skip_hw \
		action mirred egress mirror dev gt6
	ping -I h1 192.0.2.2

Fixes: e41c7c68ea ("ip6erspan: make sure enough headroom at xmit.")
Signed-off-by: Petr Machata <petrm@mellanox.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-25 16:46:03 +02:00
Petr Machata
1991e5efbf net: ip6_gre: Request headroom in __gre6_xmit()
[ Upstream commit 01b8d064d5 ]

__gre6_xmit() pushes GRE headers before handing over to ip6_tnl_xmit()
for generic IP-in-IP processing. However it doesn't make sure that there
is enough headroom to push the header to. That can lead to the panic
cited below. (Reproducer below that).

Fix by requesting either needed_headroom if already primed, or just the
bare minimum needed for the header otherwise.

[  158.576725] kernel BUG at net/core/skbuff.c:104!
[  158.581510] invalid opcode: 0000 [#1] PREEMPT SMP KASAN PTI
[  158.587174] Modules linked in: act_mirred cls_matchall ip6_gre ip6_tunnel tunnel6 gre sch_ingress vrf veth x86_pkg_temp_thermal mlx_platform nfsd e1000e leds_mlxcpld
[  158.602268] CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 4.17.0-rc4-net_master-custom-139 #10
[  158.610938] Hardware name: Mellanox Technologies Ltd. "MSN2410-CB2F"/"SA000874", BIOS 4.6.5 03/08/2016
[  158.620426] RIP: 0010:skb_panic+0xc3/0x100
[  158.624586] RSP: 0018:ffff8801d3f27110 EFLAGS: 00010286
[  158.629882] RAX: 0000000000000082 RBX: ffff8801c02cc040 RCX: 0000000000000000
[  158.637127] RDX: 0000000000000082 RSI: dffffc0000000000 RDI: ffffed003a7e4e18
[  158.644366] RBP: ffff8801bfec8020 R08: ffffed003aabce19 R09: ffffed003aabce19
[  158.651574] R10: 000000000000000b R11: ffffed003aabce18 R12: ffff8801c364de66
[  158.658786] R13: 000000000000002c R14: 00000000000000c0 R15: ffff8801c364de68
[  158.666007] FS:  0000000000000000(0000) GS:ffff8801d5400000(0000) knlGS:0000000000000000
[  158.674212] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  158.680036] CR2: 00007f4b3702dcd0 CR3: 0000000003228002 CR4: 00000000001606e0
[  158.687228] Call Trace:
[  158.689752]  ? __gre6_xmit+0x246/0xd80 [ip6_gre]
[  158.694475]  ? __gre6_xmit+0x246/0xd80 [ip6_gre]
[  158.699141]  skb_push+0x78/0x90
[  158.702344]  __gre6_xmit+0x246/0xd80 [ip6_gre]
[  158.706872]  ip6gre_tunnel_xmit+0x3bc/0x610 [ip6_gre]
[  158.711992]  ? __gre6_xmit+0xd80/0xd80 [ip6_gre]
[  158.716668]  ? debug_check_no_locks_freed+0x210/0x210
[  158.721761]  ? print_irqtrace_events+0x120/0x120
[  158.726461]  ? sched_clock_cpu+0x18/0x210
[  158.730572]  ? sched_clock_cpu+0x18/0x210
[  158.734692]  ? cyc2ns_read_end+0x10/0x10
[  158.738705]  ? skb_network_protocol+0x76/0x200
[  158.743216]  ? netif_skb_features+0x1b2/0x550
[  158.747648]  dev_hard_start_xmit+0x137/0x770
[  158.752010]  sch_direct_xmit+0x2ef/0x5d0
[  158.755992]  ? pfifo_fast_dequeue+0x3fa/0x670
[  158.760460]  ? pfifo_fast_change_tx_queue_len+0x810/0x810
[  158.765975]  ? __lock_is_held+0xa0/0x160
[  158.770002]  __qdisc_run+0x39e/0xfc0
[  158.773673]  ? _raw_spin_unlock+0x29/0x40
[  158.777781]  ? pfifo_fast_enqueue+0x24b/0x3e0
[  158.782191]  ? sch_direct_xmit+0x5d0/0x5d0
[  158.786372]  ? pfifo_fast_dequeue+0x670/0x670
[  158.790818]  ? __dev_queue_xmit+0x172/0x1770
[  158.795195]  ? preempt_count_sub+0xf/0xd0
[  158.799313]  __dev_queue_xmit+0x410/0x1770
[  158.803512]  ? ___slab_alloc+0x605/0x930
[  158.807525]  ? ___slab_alloc+0x605/0x930
[  158.811540]  ? memcpy+0x34/0x50
[  158.814768]  ? netdev_pick_tx+0x1c0/0x1c0
[  158.818895]  ? __skb_clone+0x2fd/0x3d0
[  158.822712]  ? __copy_skb_header+0x270/0x270
[  158.827079]  ? rcu_read_lock_sched_held+0x93/0xa0
[  158.831903]  ? kmem_cache_alloc+0x344/0x4d0
[  158.836199]  ? skb_clone+0x123/0x230
[  158.839869]  ? skb_split+0x820/0x820
[  158.843521]  ? tcf_mirred+0x554/0x930 [act_mirred]
[  158.848407]  tcf_mirred+0x554/0x930 [act_mirred]
[  158.853104]  ? tcf_mirred_act_wants_ingress.part.2+0x10/0x10 [act_mirred]
[  158.860005]  ? __lock_acquire+0x706/0x26e0
[  158.864162]  ? mark_lock+0x13d/0xb40
[  158.867832]  tcf_action_exec+0xcf/0x2a0
[  158.871736]  tcf_classify+0xfa/0x340
[  158.875402]  __netif_receive_skb_core+0x8e1/0x1c60
[  158.880334]  ? nf_ingress+0x500/0x500
[  158.884059]  ? process_backlog+0x347/0x4b0
[  158.888241]  ? lock_acquire+0xd8/0x320
[  158.892050]  ? process_backlog+0x1b6/0x4b0
[  158.896228]  ? process_backlog+0xc2/0x4b0
[  158.900291]  process_backlog+0xc2/0x4b0
[  158.904210]  net_rx_action+0x5cc/0x980
[  158.908047]  ? napi_complete_done+0x2c0/0x2c0
[  158.912525]  ? rcu_read_unlock+0x80/0x80
[  158.916534]  ? __lock_is_held+0x34/0x160
[  158.920541]  __do_softirq+0x1d4/0x9d2
[  158.924308]  ? trace_event_raw_event_irq_handler_exit+0x140/0x140
[  158.930515]  run_ksoftirqd+0x1d/0x40
[  158.934152]  smpboot_thread_fn+0x32b/0x690
[  158.938299]  ? sort_range+0x20/0x20
[  158.941842]  ? preempt_count_sub+0xf/0xd0
[  158.945940]  ? schedule+0x5b/0x140
[  158.949412]  kthread+0x206/0x300
[  158.952689]  ? sort_range+0x20/0x20
[  158.956249]  ? kthread_stop+0x570/0x570
[  158.960164]  ret_from_fork+0x3a/0x50
[  158.963823] Code: 14 3e ff 8b 4b 78 55 4d 89 f9 41 56 41 55 48 c7 c7 a0 cf db 82 41 54 44 8b 44 24 2c 48 8b 54 24 30 48 8b 74 24 20 e8 16 94 13 ff <0f> 0b 48 c7 c7 60 8e 1f 85 48 83 c4 20 e8 55 ef a6 ff 89 74 24
[  158.983235] RIP: skb_panic+0xc3/0x100 RSP: ffff8801d3f27110
[  158.988935] ---[ end trace 5af56ee845aa6cc8 ]---
[  158.993641] Kernel panic - not syncing: Fatal exception in interrupt
[  159.000176] Kernel Offset: disabled
[  159.003767] ---[ end Kernel panic - not syncing: Fatal exception in interrupt ]---

Reproducer:

	ip link add h1 type veth peer name swp1
	ip link add h3 type veth peer name swp3

	ip link set dev h1 up
	ip address add 192.0.2.1/28 dev h1

	ip link add dev vh3 type vrf table 20
	ip link set dev h3 master vh3
	ip link set dev vh3 up
	ip link set dev h3 up

	ip link set dev swp3 up
	ip address add dev swp3 2001:db8:2::1/64

	ip link set dev swp1 up
	tc qdisc add dev swp1 clsact

	ip link add name gt6 type ip6gretap \
		local 2001:db8:2::1 remote 2001:db8:2::2
	ip link set dev gt6 up

	sleep 1

	tc filter add dev swp1 ingress pref 1000 matchall skip_hw \
		action mirred egress mirror dev gt6
	ping -I h1 192.0.2.2

Fixes: c12b395a46 ("gre: Support GRE over IPv6")
Signed-off-by: Petr Machata <petrm@mellanox.com>
Acked-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-25 16:46:03 +02:00
Willem de Bruijn
b7fc1abdc8 net: test tailroom before appending to linear skb
[ Upstream commit 113f99c335 ]

Device features may change during transmission. In particular with
corking, a device may toggle scatter-gather in between allocating
and writing to an skb.

Do not unconditionally assume that !NETIF_F_SG at write time implies
that the same held at alloc time and thus the skb has sufficient
tailroom.

This issue predates git history.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-25 16:46:01 +02:00
Paolo Abeni
64fe605aa1 udp: fix SO_BINDTODEVICE
[ Upstream commit 69678bcd4d ]

Damir reported a breakage of SO_BINDTODEVICE for UDP sockets.
In absence of VRF devices, after commit fb74c27735 ("net:
ipv4: add second dif to udp socket lookups") the dif mismatch
isn't fatal anymore for UDP socket lookup with non null
sk_bound_dev_if, breaking SO_BINDTODEVICE semantics.

This changeset addresses the issue making the dif match mandatory
again in the above scenario.

Reported-by: Damir Mansurov <dnman@oktetlabs.ru>
Fixes: fb74c27735 ("net: ipv4: add second dif to udp socket lookups")
Fixes: 1801b570dd ("net: ipv6: add second dif to udp socket lookups")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-19 10:19:35 +02:00
Eric Dumazet
8c897b4f09 ipv6: fix uninit-value in ip6_multipath_l3_keys()
[ Upstream commit cea67a2dd6 ]

syzbot/KMSAN reported an uninit-value in ip6_multipath_l3_keys(),
root caused to a bad assumption of ICMP header being already
pulled in skb->head

ip_multipath_l3_keys() does the correct thing, so it is an IPv6 only bug.

BUG: KMSAN: uninit-value in ip6_multipath_l3_keys net/ipv6/route.c:1830 [inline]
BUG: KMSAN: uninit-value in rt6_multipath_hash+0x5c4/0x640 net/ipv6/route.c:1858
CPU: 0 PID: 4507 Comm: syz-executor661 Not tainted 4.16.0+ #87
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:683
 ip6_multipath_l3_keys net/ipv6/route.c:1830 [inline]
 rt6_multipath_hash+0x5c4/0x640 net/ipv6/route.c:1858
 ip6_route_input+0x65a/0x920 net/ipv6/route.c:1884
 ip6_rcv_finish+0x413/0x6e0 net/ipv6/ip6_input.c:69
 NF_HOOK include/linux/netfilter.h:288 [inline]
 ipv6_rcv+0x1e16/0x2340 net/ipv6/ip6_input.c:208
 __netif_receive_skb_core+0x47df/0x4a90 net/core/dev.c:4562
 __netif_receive_skb net/core/dev.c:4627 [inline]
 netif_receive_skb_internal+0x49d/0x630 net/core/dev.c:4701
 netif_receive_skb+0x230/0x240 net/core/dev.c:4725
 tun_rx_batched drivers/net/tun.c:1555 [inline]
 tun_get_user+0x740f/0x7c60 drivers/net/tun.c:1962
 tun_chr_write_iter+0x1d4/0x330 drivers/net/tun.c:1990
 call_write_iter include/linux/fs.h:1782 [inline]
 new_sync_write fs/read_write.c:469 [inline]
 __vfs_write+0x7fb/0x9f0 fs/read_write.c:482
 vfs_write+0x463/0x8d0 fs/read_write.c:544
 SYSC_write+0x172/0x360 fs/read_write.c:589
 SyS_write+0x55/0x80 fs/read_write.c:581
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2

Fixes: 23aebdacb0 ("ipv6: Compute multipath hash for ICMP errors from offending packet")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Jakub Sitnicki <jkbs@redhat.com>
Acked-by: Jakub Sitnicki <jkbs@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-19 10:19:34 +02:00
Ahmed Abdelsalam
5166ab95be ipv6: sr: fix NULL pointer dereference in seg6_do_srh_encap()- v4 pkts
[ Upstream commit a957fa190a ]

In case of seg6 in encap mode, seg6_do_srh_encap() calls set_tun_src()
in order to set the src addr of outer IPv6 header.

The net_device is required for set_tun_src(). However calling ip6_dst_idev()
on dst_entry in case of IPv4 traffic results on the following bug.

Using just dst->dev should fix this BUG.

[  196.242461] BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
[  196.242975] PGD 800000010f076067 P4D 800000010f076067 PUD 10f060067 PMD 0
[  196.243329] Oops: 0000 [#1] SMP PTI
[  196.243468] Modules linked in: nfsd auth_rpcgss nfs_acl nfs lockd grace fscache sunrpc crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcbc aesni_intel aes_x86_64 crypto_simd cryptd input_leds glue_helper led_class pcspkr serio_raw mac_hid video autofs4 hid_generic usbhid hid e1000 i2c_piix4 ahci pata_acpi libahci
[  196.244362] CPU: 2 PID: 1089 Comm: ping Not tainted 4.16.0+ #1
[  196.244606] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[  196.244968] RIP: 0010:seg6_do_srh_encap+0x1ac/0x300
[  196.245236] RSP: 0018:ffffb2ce00b23a60 EFLAGS: 00010202
[  196.245464] RAX: 0000000000000000 RBX: ffff8c7f53eea300 RCX: 0000000000000000
[  196.245742] RDX: 0000f10000000000 RSI: ffff8c7f52085a6c RDI: ffff8c7f41166850
[  196.246018] RBP: ffffb2ce00b23aa8 R08: 00000000000261e0 R09: ffff8c7f41166800
[  196.246294] R10: ffffdce5040ac780 R11: ffff8c7f41166828 R12: ffff8c7f41166808
[  196.246570] R13: ffff8c7f52085a44 R14: ffffffffb73211c0 R15: ffff8c7e69e44200
[  196.246846] FS:  00007fc448789700(0000) GS:ffff8c7f59d00000(0000) knlGS:0000000000000000
[  196.247286] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  196.247526] CR2: 0000000000000000 CR3: 000000010f05a000 CR4: 00000000000406e0
[  196.247804] Call Trace:
[  196.247972]  seg6_do_srh+0x15b/0x1c0
[  196.248156]  seg6_output+0x3c/0x220
[  196.248341]  ? prandom_u32+0x14/0x20
[  196.248526]  ? ip_idents_reserve+0x6c/0x80
[  196.248723]  ? __ip_select_ident+0x90/0x100
[  196.248923]  ? ip_append_data.part.50+0x6c/0xd0
[  196.249133]  lwtunnel_output+0x44/0x70
[  196.249328]  ip_send_skb+0x15/0x40
[  196.249515]  raw_sendmsg+0x8c3/0xac0
[  196.249701]  ? _copy_from_user+0x2e/0x60
[  196.249897]  ? rw_copy_check_uvector+0x53/0x110
[  196.250106]  ? _copy_from_user+0x2e/0x60
[  196.250299]  ? copy_msghdr_from_user+0xce/0x140
[  196.250508]  sock_sendmsg+0x36/0x40
[  196.250690]  ___sys_sendmsg+0x292/0x2a0
[  196.250881]  ? _cond_resched+0x15/0x30
[  196.251074]  ? copy_termios+0x1e/0x70
[  196.251261]  ? _copy_to_user+0x22/0x30
[  196.251575]  ? tty_mode_ioctl+0x1c3/0x4e0
[  196.251782]  ? _cond_resched+0x15/0x30
[  196.251972]  ? mutex_lock+0xe/0x30
[  196.252152]  ? vvar_fault+0xd2/0x110
[  196.252337]  ? __do_fault+0x1f/0xc0
[  196.252521]  ? __handle_mm_fault+0xc1f/0x12d0
[  196.252727]  ? __sys_sendmsg+0x63/0xa0
[  196.252919]  __sys_sendmsg+0x63/0xa0
[  196.253107]  do_syscall_64+0x72/0x200
[  196.253305]  entry_SYSCALL_64_after_hwframe+0x3d/0xa2
[  196.253530] RIP: 0033:0x7fc4480b0690
[  196.253715] RSP: 002b:00007ffde9f252f8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
[  196.254053] RAX: ffffffffffffffda RBX: 0000000000000040 RCX: 00007fc4480b0690
[  196.254331] RDX: 0000000000000000 RSI: 000000000060a360 RDI: 0000000000000003
[  196.254608] RBP: 00007ffde9f253f0 R08: 00000000002d1e81 R09: 0000000000000002
[  196.254884] R10: 00007ffde9f250c0 R11: 0000000000000246 R12: 0000000000b22070
[  196.255205] R13: 20c49ba5e353f7cf R14: 431bde82d7b634db R15: 00007ffde9f278fe
[  196.255484] Code: a5 0f b6 45 c0 41 88 41 28 41 0f b6 41 2c 48 c1 e0 04 49 8b 54 01 38 49 8b 44 01 30 49 89 51 20 49 89 41 18 48 8b 83 b0 00 00 00 <48> 8b 30 49 8b 86 08 0b 00 00 48 8b 40 20 48 8b 50 08 48 0b 10
[  196.256190] RIP: seg6_do_srh_encap+0x1ac/0x300 RSP: ffffb2ce00b23a60
[  196.256445] CR2: 0000000000000000
[  196.256676] ---[ end trace 71af7d093603885c ]---

Fixes: 8936ef7604 ("ipv6: sr: fix NULL pointer dereference when setting encap source address")
Signed-off-by: Ahmed Abdelsalam <amsalam20@gmail.com>
Acked-by: David Lebrun <dlebrun@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-29 11:35:44 +02:00
Eric Dumazet
816475da7d ipv6: add RTA_TABLE and RTA_PREFSRC to rtm_ipv6_policy
[ Upstream commit aa8f877849 ]

KMSAN reported use of uninit-value that I tracked to lack
of proper size check on RTA_TABLE attribute.

I also believe RTA_PREFSRC lacks a similar check.

Fixes: 86872cb579 ("[IPv6] route: FIB6 configuration using struct fib6_config")
Fixes: c3968a857a ("ipv6: RTA_PREFSRC support for ipv6 route source address selection")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-29 11:35:44 +02:00
Florian Westphal
7407dd814b netfilter: compat: prepare xt_compat_init_offsets to return errors
commit 9782a11efc upstream.

should have no impact, function still always returns 0.
This patch is only to ease review.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-26 11:00:38 +02:00
Florian Westphal
d11ff4ba1a netfilter: x_tables: add counters allocation wrapper
commit c84ca954ac upstream.

allows to have size checks in a single spot.
This is supposed to reduce oom situations when fuzz-testing xtables.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-26 11:00:38 +02:00
Eric Dumazet
9f13ba19dd vti6: better validate user provided tunnel names
[ Upstream commit 537b361fbc ]

Use valid_name() to make sure user does not provide illegal
device name.

Fixes: ed1efb2aef ("ipv6: Add support for IPsec virtual tunnel interfaces")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-12 12:30:01 +02:00
Eric Dumazet
961757a423 ip6_tunnel: better validate user provided tunnel names
[ Upstream commit db7a65e3ab ]

Use valid_name() to make sure user does not provide illegal
device name.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-12 12:30:01 +02:00
Eric Dumazet
d210545346 ip6_gre: better validate user provided tunnel names
[ Upstream commit 5f42df013b ]

Use dev_valid_name() to make sure user does not provide illegal
device name.

syzbot caught the following bug :

BUG: KASAN: stack-out-of-bounds in strlcpy include/linux/string.h:300 [inline]
BUG: KASAN: stack-out-of-bounds in ip6gre_tunnel_locate+0x334/0x860 net/ipv6/ip6_gre.c:339
Write of size 20 at addr ffff8801afb9f7b8 by task syzkaller851048/4466

CPU: 1 PID: 4466 Comm: syzkaller851048 Not tainted 4.16.0+ #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b9/0x29f lib/dump_stack.c:53
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0xac/0x2f5 mm/kasan/report.c:412
 check_memory_region_inline mm/kasan/kasan.c:260 [inline]
 check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267
 memcpy+0x37/0x50 mm/kasan/kasan.c:303
 strlcpy include/linux/string.h:300 [inline]
 ip6gre_tunnel_locate+0x334/0x860 net/ipv6/ip6_gre.c:339
 ip6gre_tunnel_ioctl+0x69d/0x12e0 net/ipv6/ip6_gre.c:1195
 dev_ifsioc+0x43e/0xb90 net/core/dev_ioctl.c:334
 dev_ioctl+0x69a/0xcc0 net/core/dev_ioctl.c:525
 sock_ioctl+0x47e/0x680 net/socket.c:1015
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x1cf/0x1650 fs/ioctl.c:684
 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:701
 SYSC_ioctl fs/ioctl.c:708 [inline]
 SyS_ioctl+0x24/0x30 fs/ioctl.c:706
 do_syscall_64+0x29e/0x9d0 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

Fixes: c12b395a46 ("gre: Support GRE over IPv6")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-12 12:30:01 +02:00
Eric Dumazet
e7392359da ipv6: sit: better validate user provided tunnel names
[ Upstream commit b95211e066 ]

Use dev_valid_name() to make sure user does not provide illegal
device name.

syzbot caught the following bug :

BUG: KASAN: stack-out-of-bounds in strlcpy include/linux/string.h:300 [inline]
BUG: KASAN: stack-out-of-bounds in ipip6_tunnel_locate+0x63b/0xaa0 net/ipv6/sit.c:254
Write of size 33 at addr ffff8801b64076d8 by task syzkaller932654/4453

CPU: 0 PID: 4453 Comm: syzkaller932654 Not tainted 4.16.0+ #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b9/0x29f lib/dump_stack.c:53
 print_address_description+0x6c/0x20b mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.7+0xac/0x2f5 mm/kasan/report.c:412
 check_memory_region_inline mm/kasan/kasan.c:260 [inline]
 check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267
 memcpy+0x37/0x50 mm/kasan/kasan.c:303
 strlcpy include/linux/string.h:300 [inline]
 ipip6_tunnel_locate+0x63b/0xaa0 net/ipv6/sit.c:254
 ipip6_tunnel_ioctl+0xe71/0x241b net/ipv6/sit.c:1221
 dev_ifsioc+0x43e/0xb90 net/core/dev_ioctl.c:334
 dev_ioctl+0x69a/0xcc0 net/core/dev_ioctl.c:525
 sock_ioctl+0x47e/0x680 net/socket.c:1015
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x1cf/0x1650 fs/ioctl.c:684
 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:701
 SYSC_ioctl fs/ioctl.c:708 [inline]
 SyS_ioctl+0x24/0x30 fs/ioctl.c:706
 do_syscall_64+0x29e/0x9d0 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-12 12:30:00 +02:00
Jeff Barnhill
22034921c6 net/ipv6: Increment OUTxxx counters after netfilter hook
[ Upstream commit 71a1c91523 ]

At the end of ip6_forward(), IPSTATS_MIB_OUTFORWDATAGRAMS and
IPSTATS_MIB_OUTOCTETS are incremented immediately before the NF_HOOK call
for NFPROTO_IPV6 / NF_INET_FORWARD.  As a result, these counters get
incremented regardless of whether or not the netfilter hook allows the
packet to continue being processed.  This change increments the counters
in ip6_forward_finish() so that it will not happen if the netfilter hook
chooses to terminate the packet, which is similar to how IPv4 works.

Signed-off-by: Jeff Barnhill <0xeffeff@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-12 12:29:59 +02:00
David Ahern
b6cdbc8523 net/ipv6: Fix route leaking between VRFs
Donald reported that IPv6 route leaking between VRFs is not working.
The root cause is the strict argument in the call to rt6_lookup when
validating the nexthop spec.

ip6_route_check_nh validates the gateway and device (if given) of a
route spec. It in turn could call rt6_lookup (e.g., lookup in a given
table did not succeed so it falls back to a full lookup) and if so
sets the strict argument to 1. That means if the egress device is given,
the route lookup needs to return a result with the same device. This
strict requirement does not work with VRFs (IPv4 or IPv6) because the
oif in the flow struct is overridden with the index of the VRF device
to trigger a match on the l3mdev rule and force the lookup to its table.

The right long term solution is to add an l3mdev index to the flow
struct such that the oif is not overridden. That solution will not
backport well, so this patch aims for a simpler solution to relax the
strict argument if the route spec device is an l3mdev slave. As done
in other places, use the FLOWI_FLAG_SKIP_NH_OIF to know that the
RT6_LOOKUP_F_IFACE flag needs to be removed.

Fixes: ca254490c8 ("net: Add VRF support to IPv6 stack")
Reported-by: Donald Sharp <sharpd@cumulusnetworks.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-30 14:23:59 -04:00
David Lebrun
5807b22c91 ipv6: sr: fix seg6 encap performances with TSO enabled
Enabling TSO can lead to abysmal performances when using seg6 in
encap mode, such as with the ixgbe driver. This patch adds a call to
iptunnel_handle_offloads() to remove the encapsulation bit if needed.

Before:
root@comp4-seg6bpf:~# iperf3 -c fc00::55
Connecting to host fc00::55, port 5201
[  4] local fc45::4 port 36592 connected to fc00::55 port 5201
[ ID] Interval           Transfer     Bandwidth       Retr  Cwnd
[  4]   0.00-1.00   sec   196 KBytes  1.60 Mbits/sec   47   6.66 KBytes
[  4]   1.00-2.00   sec   304 KBytes  2.49 Mbits/sec  100   5.33 KBytes
[  4]   2.00-3.00   sec   284 KBytes  2.32 Mbits/sec   92   5.33 KBytes

After:
root@comp4-seg6bpf:~# iperf3 -c fc00::55
Connecting to host fc00::55, port 5201
[  4] local fc45::4 port 43062 connected to fc00::55 port 5201
[ ID] Interval           Transfer     Bandwidth       Retr  Cwnd
[  4]   0.00-1.00   sec  1.03 GBytes  8.89 Gbits/sec    0    743 KBytes
[  4]   1.00-2.00   sec  1.03 GBytes  8.87 Gbits/sec    0    743 KBytes
[  4]   2.00-3.00   sec  1.03 GBytes  8.87 Gbits/sec    0    743 KBytes

Reported-by: Tom Herbert <tom@quantonium.net>
Fixes: 6c8702c60b ("ipv6: sr: add support for SRH encapsulation and injection with lwtunnels")
Signed-off-by: David Lebrun <dlebrun@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-30 14:14:33 -04:00
David S. Miller
020295d95e Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec
Steffen Klassert says:

====================
pull request (net): ipsec 2018-03-29

1) Fix a rcu_read_lock/rcu_read_unlock imbalance
   in the error path of xfrm_local_error().
   From Taehee Yoo.

2) Some VTI MTU fixes. From Stefano Brivio.

3) Fix a too early overwritten skb control buffer
   on xfrm transport mode.

Please note that this pull request has a merge conflict
in net/ipv4/ip_tunnel.c.

The conflict is between

commit f6cc9c054e ("ip_tunnel: Emit events for post-register MTU changes")

from the net tree and

commit 24fc79798b ("ip_tunnel: Clamp MTU to bounds on new link")

from the ipsec tree.

It can be solved as it is currently done in linux-next.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-29 10:12:47 -04:00
Paolo Abeni
10b8a3de60 ipv6: the entire IPv6 header chain must fit the first fragment
While building ipv6 datagram we currently allow arbitrary large
extheaders, even beyond pmtu size. The syzbot has found a way
to exploit the above to trigger the following splat:

kernel BUG at ./include/linux/skbuff.h:2073!
invalid opcode: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
    (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 4230 Comm: syzkaller672661 Not tainted 4.16.0-rc2+ #326
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:__skb_pull include/linux/skbuff.h:2073 [inline]
RIP: 0010:__ip6_make_skb+0x1ac8/0x2190 net/ipv6/ip6_output.c:1636
RSP: 0018:ffff8801bc18f0f0 EFLAGS: 00010293
RAX: ffff8801b17400c0 RBX: 0000000000000738 RCX: ffffffff84f01828
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8801b415ac18
RBP: ffff8801bc18f360 R08: ffff8801b4576844 R09: 0000000000000000
R10: ffff8801bc18f380 R11: ffffed00367aee4e R12: 00000000000000d6
R13: ffff8801b415a740 R14: dffffc0000000000 R15: ffff8801b45767c0
FS:  0000000001535880(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000002000b000 CR3: 00000001b4123001 CR4: 00000000001606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
  ip6_finish_skb include/net/ipv6.h:969 [inline]
  udp_v6_push_pending_frames+0x269/0x3b0 net/ipv6/udp.c:1073
  udpv6_sendmsg+0x2a96/0x3400 net/ipv6/udp.c:1343
  inet_sendmsg+0x11f/0x5e0 net/ipv4/af_inet.c:764
  sock_sendmsg_nosec net/socket.c:630 [inline]
  sock_sendmsg+0xca/0x110 net/socket.c:640
  ___sys_sendmsg+0x320/0x8b0 net/socket.c:2046
  __sys_sendmmsg+0x1ee/0x620 net/socket.c:2136
  SYSC_sendmmsg net/socket.c:2167 [inline]
  SyS_sendmmsg+0x35/0x60 net/socket.c:2162
  do_syscall_64+0x280/0x940 arch/x86/entry/common.c:287
  entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x4404c9
RSP: 002b:00007ffdce35f948 EFLAGS: 00000217 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004404c9
RDX: 0000000000000003 RSI: 0000000020001f00 RDI: 0000000000000003
RBP: 00000000006cb018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 0000000020000080 R11: 0000000000000217 R12: 0000000000401df0
R13: 0000000000401e80 R14: 0000000000000000 R15: 0000000000000000
Code: ff e8 1d 5e b9 fc e9 15 e9 ff ff e8 13 5e b9 fc e9 44 e8 ff ff e8 29
5e b9 fc e9 c0 e6 ff ff e8 3f f3 80 fc 0f 0b e8 38 f3 80 fc <0f> 0b 49 8d
87 80 00 00 00 4d 8d 87 84 00 00 00 48 89 85 20 fe
RIP: __skb_pull include/linux/skbuff.h:2073 [inline] RSP: ffff8801bc18f0f0
RIP: __ip6_make_skb+0x1ac8/0x2190 net/ipv6/ip6_output.c:1636 RSP:
ffff8801bc18f0f0

As stated by RFC 7112 section 5:

   When a host fragments an IPv6 datagram, it MUST include the entire
   IPv6 Header Chain in the First Fragment.

So this patch addresses the issue dropping datagrams with excessive
extheader length. It also updates the error path to report to the
calling socket nonnegative pmtu values.

The issue apparently predates git history.

v1 -> v2: cleanup error path, as per Eric's suggestion

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: syzbot+91e6f9932ff122fa4410@syzkaller.appspotmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-25 21:17:20 -04:00
Hans Wippel
bc58a1baf2 net/ipv4: disable SMC TCP option with SYN Cookies
Currently, the SMC experimental TCP option in a SYN packet is lost on
the server side when SYN Cookies are active. However, the corresponding
SYNACK sent back to the client contains the SMC option. This causes an
inconsistent view of the SMC capabilities on the client and server.

This patch disables the SMC option in the SYNACK when SYN Cookies are
active to avoid this issue.

Fixes: 60e2a77807 ("tcp: TCP experimental option for SMC")
Signed-off-by: Hans Wippel <hwippel@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-25 20:53:54 -04:00
David S. Miller
b9ee96b45f 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 your net tree,
they are:

1) Don't pick fixed hash implementation for NFT_SET_EVAL sets, otherwise
   userspace hits EOPNOTSUPP with valid rules using the meter statement,
   from Florian Westphal.

2) If you send a batch that flushes the existing ruleset (that contains
   a NAT chain) and the new ruleset definition comes with a new NAT
   chain, don't bogusly hit EBUSY. Also from Florian.

3) Missing netlink policy attribute validation, from Florian.

4) Detach conntrack template from skbuff if IP_NODEFRAG is set on,
   from Paolo Abeni.

5) Cache device names in flowtable object, otherwise we may end up
   walking over devices going aways given no rtnl_lock is held.

6) Fix incorrect net_device ingress with ingress hooks.

7) Fix crash when trying to read more data than available in UDP
   packets from the nf_socket infrastructure, from Subash.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-24 17:10:01 -04:00
Subash Abhinov Kasiviswanathan
32c1733f0d netfilter: nf_socket: Fix out of bounds access in nf_sk_lookup_slow_v{4,6}
skb_header_pointer will copy data into a buffer if data is non linear,
otherwise it will return a pointer in the linear section of the data.
nf_sk_lookup_slow_v{4,6} always copies data of size udphdr but later
accesses memory within the size of tcphdr (th->doff) in case of TCP
packets. This causes a crash when running with KASAN with the following
call stack -

BUG: KASAN: stack-out-of-bounds in xt_socket_lookup_slow_v4+0x524/0x718
net/netfilter/xt_socket.c:178
Read of size 2 at addr ffffffe3d417a87c by task syz-executor/28971
CPU: 2 PID: 28971 Comm: syz-executor Tainted: G    B   W  O    4.9.65+ #1
Call trace:
[<ffffff9467e8d390>] dump_backtrace+0x0/0x428 arch/arm64/kernel/traps.c:76
[<ffffff9467e8d7e0>] show_stack+0x28/0x38 arch/arm64/kernel/traps.c:226
[<ffffff946842d9b8>] __dump_stack lib/dump_stack.c:15 [inline]
[<ffffff946842d9b8>] dump_stack+0xd4/0x124 lib/dump_stack.c:51
[<ffffff946811d4b0>] print_address_description+0x68/0x258 mm/kasan/report.c:248
[<ffffff946811d8c8>] kasan_report_error mm/kasan/report.c:347 [inline]
[<ffffff946811d8c8>] kasan_report.part.2+0x228/0x2f0 mm/kasan/report.c:371
[<ffffff946811df44>] kasan_report+0x5c/0x70 mm/kasan/report.c:372
[<ffffff946811bebc>] check_memory_region_inline mm/kasan/kasan.c:308 [inline]
[<ffffff946811bebc>] __asan_load2+0x84/0x98 mm/kasan/kasan.c:739
[<ffffff94694d6f04>] __tcp_hdrlen include/linux/tcp.h:35 [inline]
[<ffffff94694d6f04>] xt_socket_lookup_slow_v4+0x524/0x718 net/netfilter/xt_socket.c:178

Fix this by copying data into appropriate size headers based on protocol.

Fixes: a583636a83 ("inet: refactor inet[6]_lookup functions to take skb")
Signed-off-by: Tejaswi Tanikella <tejaswit@codeaurora.org>
Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-03-24 21:17:14 +01:00
Eric Dumazet
1bfa26ff8c ipv6: fix possible deadlock in rt6_age_examine_exception()
syzbot reported a LOCKDEP splat [1] in rt6_age_examine_exception()

rt6_age_examine_exception() is called while rt6_exception_lock is held.
This lock is the lower one in the lock hierarchy, thus we can not
call dst_neigh_lookup() function, as it can fallback to neigh_create()

We should instead do a pure RCU lookup. As a bonus we avoid
a pair of atomic operations on neigh refcount.

[1]

WARNING: possible circular locking dependency detected
4.16.0-rc4+ #277 Not tainted

syz-executor7/4015 is trying to acquire lock:
 (&ndev->lock){++--}, at: [<00000000416dce19>] __ipv6_dev_mc_dec+0x45/0x350 net/ipv6/mcast.c:928

but task is already holding lock:
 (&tbl->lock){++-.}, at: [<00000000b5cb1d65>] neigh_ifdown+0x3d/0x250 net/core/neighbour.c:292

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #3 (&tbl->lock){++-.}:
       __raw_write_lock_bh include/linux/rwlock_api_smp.h:203 [inline]
       _raw_write_lock_bh+0x31/0x40 kernel/locking/spinlock.c:312
       __neigh_create+0x87e/0x1d90 net/core/neighbour.c:528
       neigh_create include/net/neighbour.h:315 [inline]
       ip6_neigh_lookup+0x9a7/0xba0 net/ipv6/route.c:228
       dst_neigh_lookup include/net/dst.h:405 [inline]
       rt6_age_examine_exception net/ipv6/route.c:1609 [inline]
       rt6_age_exceptions+0x381/0x660 net/ipv6/route.c:1645
       fib6_age+0xfb/0x140 net/ipv6/ip6_fib.c:2033
       fib6_clean_node+0x389/0x580 net/ipv6/ip6_fib.c:1919
       fib6_walk_continue+0x46c/0x8a0 net/ipv6/ip6_fib.c:1845
       fib6_walk+0x91/0xf0 net/ipv6/ip6_fib.c:1893
       fib6_clean_tree+0x1e6/0x340 net/ipv6/ip6_fib.c:1970
       __fib6_clean_all+0x1f4/0x3a0 net/ipv6/ip6_fib.c:1986
       fib6_clean_all net/ipv6/ip6_fib.c:1997 [inline]
       fib6_run_gc+0x16b/0x3c0 net/ipv6/ip6_fib.c:2053
       ndisc_netdev_event+0x3c2/0x4a0 net/ipv6/ndisc.c:1781
       notifier_call_chain+0x136/0x2c0 kernel/notifier.c:93
       __raw_notifier_call_chain kernel/notifier.c:394 [inline]
       raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401
       call_netdevice_notifiers_info+0x32/0x70 net/core/dev.c:1707
       call_netdevice_notifiers net/core/dev.c:1725 [inline]
       __dev_notify_flags+0x262/0x430 net/core/dev.c:6960
       dev_change_flags+0xf5/0x140 net/core/dev.c:6994
       devinet_ioctl+0x126a/0x1ac0 net/ipv4/devinet.c:1080
       inet_ioctl+0x184/0x310 net/ipv4/af_inet.c:919
       sock_do_ioctl+0xef/0x390 net/socket.c:957
       sock_ioctl+0x36b/0x610 net/socket.c:1081
       vfs_ioctl fs/ioctl.c:46 [inline]
       do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686
       SYSC_ioctl fs/ioctl.c:701 [inline]
       SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
       do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
       entry_SYSCALL_64_after_hwframe+0x42/0xb7

-> #2 (rt6_exception_lock){+.-.}:
       __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
       _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:168
       spin_lock_bh include/linux/spinlock.h:315 [inline]
       rt6_flush_exceptions+0x21/0x210 net/ipv6/route.c:1367
       fib6_del_route net/ipv6/ip6_fib.c:1677 [inline]
       fib6_del+0x624/0x12c0 net/ipv6/ip6_fib.c:1761
       __ip6_del_rt+0xc7/0x120 net/ipv6/route.c:2980
       ip6_del_rt+0x132/0x1a0 net/ipv6/route.c:2993
       __ipv6_dev_ac_dec+0x3b1/0x600 net/ipv6/anycast.c:332
       ipv6_dev_ac_dec net/ipv6/anycast.c:345 [inline]
       ipv6_sock_ac_close+0x2b4/0x3e0 net/ipv6/anycast.c:200
       inet6_release+0x48/0x70 net/ipv6/af_inet6.c:433
       sock_release+0x8d/0x1e0 net/socket.c:594
       sock_close+0x16/0x20 net/socket.c:1149
       __fput+0x327/0x7e0 fs/file_table.c:209
       ____fput+0x15/0x20 fs/file_table.c:243
       task_work_run+0x199/0x270 kernel/task_work.c:113
       exit_task_work include/linux/task_work.h:22 [inline]
       do_exit+0x9bb/0x1ad0 kernel/exit.c:865
       do_group_exit+0x149/0x400 kernel/exit.c:968
       get_signal+0x73a/0x16d0 kernel/signal.c:2469
       do_signal+0x90/0x1e90 arch/x86/kernel/signal.c:809
       exit_to_usermode_loop+0x258/0x2f0 arch/x86/entry/common.c:162
       prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
       syscall_return_slowpath arch/x86/entry/common.c:265 [inline]
       do_syscall_64+0x6ec/0x940 arch/x86/entry/common.c:292
       entry_SYSCALL_64_after_hwframe+0x42/0xb7

-> #1 (&(&tb->tb6_lock)->rlock){+.-.}:
       __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
       _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:168
       spin_lock_bh include/linux/spinlock.h:315 [inline]
       __ip6_ins_rt+0x56/0x90 net/ipv6/route.c:1007
       ip6_route_add+0x141/0x190 net/ipv6/route.c:2955
       addrconf_prefix_route+0x44f/0x620 net/ipv6/addrconf.c:2359
       fixup_permanent_addr net/ipv6/addrconf.c:3368 [inline]
       addrconf_permanent_addr net/ipv6/addrconf.c:3391 [inline]
       addrconf_notify+0x1ad2/0x2310 net/ipv6/addrconf.c:3460
       notifier_call_chain+0x136/0x2c0 kernel/notifier.c:93
       __raw_notifier_call_chain kernel/notifier.c:394 [inline]
       raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401
       call_netdevice_notifiers_info+0x32/0x70 net/core/dev.c:1707
       call_netdevice_notifiers net/core/dev.c:1725 [inline]
       __dev_notify_flags+0x15d/0x430 net/core/dev.c:6958
       dev_change_flags+0xf5/0x140 net/core/dev.c:6994
       do_setlink+0xa22/0x3bb0 net/core/rtnetlink.c:2357
       rtnl_newlink+0xf37/0x1a50 net/core/rtnetlink.c:2965
       rtnetlink_rcv_msg+0x57f/0xb10 net/core/rtnetlink.c:4641
       netlink_rcv_skb+0x14b/0x380 net/netlink/af_netlink.c:2444
       rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:4659
       netlink_unicast_kernel net/netlink/af_netlink.c:1308 [inline]
       netlink_unicast+0x4c4/0x6b0 net/netlink/af_netlink.c:1334
       netlink_sendmsg+0xa4a/0xe60 net/netlink/af_netlink.c:1897
       sock_sendmsg_nosec net/socket.c:629 [inline]
       sock_sendmsg+0xca/0x110 net/socket.c:639
       ___sys_sendmsg+0x767/0x8b0 net/socket.c:2047
       __sys_sendmsg+0xe5/0x210 net/socket.c:2081
       SYSC_sendmsg net/socket.c:2092 [inline]
       SyS_sendmsg+0x2d/0x50 net/socket.c:2088
       do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
       entry_SYSCALL_64_after_hwframe+0x42/0xb7

-> #0 (&ndev->lock){++--}:
       lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3920
       __raw_write_lock_bh include/linux/rwlock_api_smp.h:203 [inline]
       _raw_write_lock_bh+0x31/0x40 kernel/locking/spinlock.c:312
       __ipv6_dev_mc_dec+0x45/0x350 net/ipv6/mcast.c:928
       ipv6_dev_mc_dec+0x110/0x1f0 net/ipv6/mcast.c:961
       pndisc_destructor+0x21a/0x340 net/ipv6/ndisc.c:392
       pneigh_ifdown net/core/neighbour.c:695 [inline]
       neigh_ifdown+0x149/0x250 net/core/neighbour.c:294
       rt6_disable_ip+0x537/0x700 net/ipv6/route.c:3874
       addrconf_ifdown+0x14b/0x14f0 net/ipv6/addrconf.c:3633
       addrconf_notify+0x5f8/0x2310 net/ipv6/addrconf.c:3557
       notifier_call_chain+0x136/0x2c0 kernel/notifier.c:93
       __raw_notifier_call_chain kernel/notifier.c:394 [inline]
       raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401
       call_netdevice_notifiers_info+0x32/0x70 net/core/dev.c:1707
       call_netdevice_notifiers net/core/dev.c:1725 [inline]
       __dev_notify_flags+0x262/0x430 net/core/dev.c:6960
       dev_change_flags+0xf5/0x140 net/core/dev.c:6994
       devinet_ioctl+0x126a/0x1ac0 net/ipv4/devinet.c:1080
       inet_ioctl+0x184/0x310 net/ipv4/af_inet.c:919
       packet_ioctl+0x1ff/0x310 net/packet/af_packet.c:4066
       sock_do_ioctl+0xef/0x390 net/socket.c:957
       sock_ioctl+0x36b/0x610 net/socket.c:1081
       vfs_ioctl fs/ioctl.c:46 [inline]
       do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686
       SYSC_ioctl fs/ioctl.c:701 [inline]
       SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
       do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
       entry_SYSCALL_64_after_hwframe+0x42/0xb7

other info that might help us debug this:

Chain exists of:
  &ndev->lock --> rt6_exception_lock --> &tbl->lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&tbl->lock);
                               lock(rt6_exception_lock);
                               lock(&tbl->lock);
  lock(&ndev->lock);

 *** DEADLOCK ***

2 locks held by syz-executor7/4015:
 #0:  (rtnl_mutex){+.+.}, at: [<00000000a2f16daa>] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74
 #1:  (&tbl->lock){++-.}, at: [<00000000b5cb1d65>] neigh_ifdown+0x3d/0x250 net/core/neighbour.c:292

stack backtrace:
CPU: 0 PID: 4015 Comm: syz-executor7 Not tainted 4.16.0-rc4+ #277
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x24d lib/dump_stack.c:53
 print_circular_bug.isra.38+0x2cd/0x2dc kernel/locking/lockdep.c:1223
 check_prev_add kernel/locking/lockdep.c:1863 [inline]
 check_prevs_add kernel/locking/lockdep.c:1976 [inline]
 validate_chain kernel/locking/lockdep.c:2417 [inline]
 __lock_acquire+0x30a8/0x3e00 kernel/locking/lockdep.c:3431
 lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3920
 __raw_write_lock_bh include/linux/rwlock_api_smp.h:203 [inline]
 _raw_write_lock_bh+0x31/0x40 kernel/locking/spinlock.c:312
 __ipv6_dev_mc_dec+0x45/0x350 net/ipv6/mcast.c:928
 ipv6_dev_mc_dec+0x110/0x1f0 net/ipv6/mcast.c:961
 pndisc_destructor+0x21a/0x340 net/ipv6/ndisc.c:392
 pneigh_ifdown net/core/neighbour.c:695 [inline]
 neigh_ifdown+0x149/0x250 net/core/neighbour.c:294
 rt6_disable_ip+0x537/0x700 net/ipv6/route.c:3874
 addrconf_ifdown+0x14b/0x14f0 net/ipv6/addrconf.c:3633
 addrconf_notify+0x5f8/0x2310 net/ipv6/addrconf.c:3557
 notifier_call_chain+0x136/0x2c0 kernel/notifier.c:93
 __raw_notifier_call_chain kernel/notifier.c:394 [inline]
 raw_notifier_call_chain+0x2d/0x40 kernel/notifier.c:401
 call_netdevice_notifiers_info+0x32/0x70 net/core/dev.c:1707
 call_netdevice_notifiers net/core/dev.c:1725 [inline]
 __dev_notify_flags+0x262/0x430 net/core/dev.c:6960
 dev_change_flags+0xf5/0x140 net/core/dev.c:6994
 devinet_ioctl+0x126a/0x1ac0 net/ipv4/devinet.c:1080
 inet_ioctl+0x184/0x310 net/ipv4/af_inet.c:919
 packet_ioctl+0x1ff/0x310 net/packet/af_packet.c:4066
 sock_do_ioctl+0xef/0x390 net/socket.c:957
 sock_ioctl+0x36b/0x610 net/socket.c:1081
 vfs_ioctl fs/ioctl.c:46 [inline]
 do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:686
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

Fixes: c757faa8bf ("ipv6: prepare fib6_age() for exception table")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Wei Wang <weiwan@google.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Acked-by: Wei Wang <weiwan@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-23 13:40:34 -04:00
David Ahern
68e2ffdeb5 net/ipv6: Handle onlink flag with multipath routes
For multipath routes the ONLINK flag can be specified per nexthop in
rtnh_flags or globally in rtm_flags. Update ip6_route_multipath_add
to consider the ONLINK setting coming from rtnh_flags. Each loop over
nexthops the config for the sibling route is initialized to the global
config and then per nexthop settings overlayed. The flag is 'or'ed into
fib6_config to handle the ONLINK flag coming from either rtm_flags or
rtnh_flags.

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>
2018-03-22 12:40:04 -04:00
David Lebrun
8936ef7604 ipv6: sr: fix NULL pointer dereference when setting encap source address
When using seg6 in encap mode, we call ipv6_dev_get_saddr() to set the
source address of the outer IPv6 header, in case none was specified.
Using skb->dev can lead to BUG() when it is in an inconsistent state.
This patch uses the net_device attached to the skb's dst instead.

[940807.667429] BUG: unable to handle kernel NULL pointer dereference at 000000000000047c
[940807.762427] IP: ipv6_dev_get_saddr+0x8b/0x1d0
[940807.815725] PGD 0 P4D 0
[940807.847173] Oops: 0000 [#1] SMP PTI
[940807.890073] Modules linked in:
[940807.927765] CPU: 6 PID: 0 Comm: swapper/6 Tainted: G        W        4.16.0-rc1-seg6bpf+ #2
[940808.028988] Hardware name: HP ProLiant DL120 G6/ProLiant DL120 G6, BIOS O26    09/06/2010
[940808.128128] RIP: 0010:ipv6_dev_get_saddr+0x8b/0x1d0
[940808.187667] RSP: 0018:ffff88043fd836b0 EFLAGS: 00010206
[940808.251366] RAX: 0000000000000005 RBX: ffff88042cb1c860 RCX: 00000000000000fe
[940808.338025] RDX: 00000000000002c0 RSI: ffff88042cb1c860 RDI: 0000000000004500
[940808.424683] RBP: ffff88043fd83740 R08: 0000000000000000 R09: ffffffffffffffff
[940808.511342] R10: 0000000000000040 R11: 0000000000000000 R12: ffff88042cb1c850
[940808.598012] R13: ffffffff8208e380 R14: ffff88042ac8da00 R15: 0000000000000002
[940808.684675] FS:  0000000000000000(0000) GS:ffff88043fd80000(0000) knlGS:0000000000000000
[940808.783036] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[940808.852975] CR2: 000000000000047c CR3: 00000004255fe000 CR4: 00000000000006e0
[940808.939634] Call Trace:
[940808.970041]  <IRQ>
[940808.995250]  ? ip6t_do_table+0x265/0x640
[940809.043341]  seg6_do_srh_encap+0x28f/0x300
[940809.093516]  ? seg6_do_srh+0x1a0/0x210
[940809.139528]  seg6_do_srh+0x1a0/0x210
[940809.183462]  seg6_output+0x28/0x1e0
[940809.226358]  lwtunnel_output+0x3f/0x70
[940809.272370]  ip6_xmit+0x2b8/0x530
[940809.313185]  ? ac6_proc_exit+0x20/0x20
[940809.359197]  inet6_csk_xmit+0x7d/0xc0
[940809.404173]  tcp_transmit_skb+0x548/0x9a0
[940809.453304]  __tcp_retransmit_skb+0x1a8/0x7a0
[940809.506603]  ? ip6_default_advmss+0x40/0x40
[940809.557824]  ? tcp_current_mss+0x24/0x90
[940809.605925]  tcp_retransmit_skb+0xd/0x80
[940809.654016]  tcp_xmit_retransmit_queue.part.17+0xf9/0x210
[940809.719797]  tcp_ack+0xa47/0x1110
[940809.760612]  tcp_rcv_established+0x13c/0x570
[940809.812865]  tcp_v6_do_rcv+0x151/0x3d0
[940809.858879]  tcp_v6_rcv+0xa5c/0xb10
[940809.901770]  ? seg6_output+0xdd/0x1e0
[940809.946745]  ip6_input_finish+0xbb/0x460
[940809.994837]  ip6_input+0x74/0x80
[940810.034612]  ? ip6_rcv_finish+0xb0/0xb0
[940810.081663]  ipv6_rcv+0x31c/0x4c0
...

Fixes: 6c8702c60b ("ipv6: sr: add support for SRH encapsulation and injection with lwtunnels")
Reported-by: Tom Herbert <tom@quantonium.net>
Signed-off-by: David Lebrun <dlebrun@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-22 12:22:45 -04:00
David Lebrun
191f86ca8e ipv6: sr: fix scheduling in RCU when creating seg6 lwtunnel state
The seg6_build_state() function is called with RCU read lock held,
so we cannot use GFP_KERNEL. This patch uses GFP_ATOMIC instead.

[   92.770271] =============================
[   92.770628] WARNING: suspicious RCU usage
[   92.770921] 4.16.0-rc4+ #12 Not tainted
[   92.771277] -----------------------------
[   92.771585] ./include/linux/rcupdate.h:302 Illegal context switch in RCU read-side critical section!
[   92.772279]
[   92.772279] other info that might help us debug this:
[   92.772279]
[   92.773067]
[   92.773067] rcu_scheduler_active = 2, debug_locks = 1
[   92.773514] 2 locks held by ip/2413:
[   92.773765]  #0:  (rtnl_mutex){+.+.}, at: [<00000000e5461720>] rtnetlink_rcv_msg+0x441/0x4d0
[   92.774377]  #1:  (rcu_read_lock){....}, at: [<00000000df4f161e>] lwtunnel_build_state+0x59/0x210
[   92.775065]
[   92.775065] stack backtrace:
[   92.775371] CPU: 0 PID: 2413 Comm: ip Not tainted 4.16.0-rc4+ #12
[   92.775791] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1.fc27 04/01/2014
[   92.776608] Call Trace:
[   92.776852]  dump_stack+0x7d/0xbc
[   92.777130]  __schedule+0x133/0xf00
[   92.777393]  ? unwind_get_return_address_ptr+0x50/0x50
[   92.777783]  ? __sched_text_start+0x8/0x8
[   92.778073]  ? rcu_is_watching+0x19/0x30
[   92.778383]  ? kernel_text_address+0x49/0x60
[   92.778800]  ? __kernel_text_address+0x9/0x30
[   92.779241]  ? unwind_get_return_address+0x29/0x40
[   92.779727]  ? pcpu_alloc+0x102/0x8f0
[   92.780101]  _cond_resched+0x23/0x50
[   92.780459]  __mutex_lock+0xbd/0xad0
[   92.780818]  ? pcpu_alloc+0x102/0x8f0
[   92.781194]  ? seg6_build_state+0x11d/0x240
[   92.781611]  ? save_stack+0x9b/0xb0
[   92.781965]  ? __ww_mutex_wakeup_for_backoff+0xf0/0xf0
[   92.782480]  ? seg6_build_state+0x11d/0x240
[   92.782925]  ? lwtunnel_build_state+0x1bd/0x210
[   92.783393]  ? ip6_route_info_create+0x687/0x1640
[   92.783846]  ? ip6_route_add+0x74/0x110
[   92.784236]  ? inet6_rtm_newroute+0x8a/0xd0

Fixes: 6c8702c60b ("ipv6: sr: add support for SRH encapsulation and injection with lwtunnels")
Signed-off-by: David Lebrun <dlebrun@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-22 12:21:11 -04:00
Stefano Brivio
5f2fb802ee ipv6: old_dport should be a __be16 in __ip6_datagram_connect()
Fixes: 2f987a76a9 ("net: ipv6: keep sk status consistent after datagram connect failure")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-20 12:43:43 -04:00
Stefano Brivio
f8a554b4aa vti6: Fix dev->max_mtu setting
We shouldn't allow a tunnel to have IP_MAX_MTU as MTU, because
another IPv6 header is going on top of our packets. Without this
patch, we might end up building packets bigger than IP_MAX_MTU.

Fixes: b96f9afee4 ("ipv4/6: use core net MTU range checking")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Acked-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2018-03-19 08:45:50 +01:00
Stefano Brivio
7a67e69a33 vti6: Keep set MTU on link creation or change, validate it
In vti6_link_config(), if MTU is already given on link creation
or change, validate and use it instead of recomputing it. To do
that, we need to propagate the knowledge that MTU was set by
userspace all the way down to vti6_link_config().

To keep this simple, vti6_dev_init() sets the new 'keep_mtu'
argument of vti6_link_config() to true: on initialization, we
don't have convenient access to netlink attributes there, but we
will anyway check whether dev->mtu is set in vti6_link_config().
If it's non-zero, it was set to the value of the IFLA_MTU
attribute during creation. Otherwise, determine a reasonable
value.

Fixes: ed1efb2aef ("ipv6: Add support for IPsec virtual tunnel interfaces")
Fixes: 53c81e95df ("ip6_vti: adjust vti mtu according to mtu of lower device")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Acked-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2018-03-19 08:45:50 +01:00
Stefano Brivio
c6741fbed6 vti6: Properly adjust vti6 MTU from MTU of lower device
If a lower device is found, we don't need to subtract
LL_MAX_HEADER to calculate our MTU: just use its MTU, the link
layer headers are already taken into account by it.

If the lower device is not found, start from ETH_DATA_LEN
instead, and only in this case subtract a worst-case
LL_MAX_HEADER.

We then need to subtract our additional IPv6 header from the
calculation.

While at it, note that vti6 doesn't have a hardware header, so
it doesn't need to set dev->hard_header_len. And as
vti6_link_config() now always sets the MTU, there's no need to
set a default value in vti6_dev_setup().

This makes the behaviour consistent with IPv4 vti, after
commit a32452366b ("vti4: Don't count header length twice."),
which was accidentally reverted by merge commit f895f0cfbb
("Merge branch 'master' of
git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec").

While commit 53c81e95df ("ip6_vti: adjust vti mtu according to
mtu of lower device") improved on the original situation, this
was still not ideal. As reported in that commit message itself,
if we start from an underlying veth MTU of 9000, we end up with
an MTU of 8832, that is, 9000 - LL_MAX_HEADER - sizeof(ipv6hdr).
This should simply be 8880, or 9000 - sizeof(ipv6hdr) instead:
we found the lower device (veth) and we know we don't have any
additional link layer header, so there's no need to subtract an
hypothetical worst-case number.

Fixes: 53c81e95df ("ip6_vti: adjust vti mtu according to mtu of lower device")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Acked-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2018-03-19 08:45:50 +01:00
David S. Miller
d2ddf628e9 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec
Steffen Klassert says:

====================
pull request (net): ipsec 2018-03-13

1) Refuse to insert 32 bit userspace socket policies on 64
   bit systems like we do it for standard policies. We don't
   have a compat layer, so inserting socket policies from
   32 bit userspace will lead to a broken configuration.

2) Make the policy hold queue work without the flowcache.
   Dummy bundles are not chached anymore, so we need to
   generate a new one on each lookup as long as the SAs
   are not yet in place.

3) Fix the validation of the esn replay attribute. The
   The sanity check in verify_replay() is bypassed if
   the XFRM_STATE_ESN flag is not set. Fix this by doing
   the sanity check uncoditionally.
   From Florian Westphal.

4) After most of the dst_entry garbage collection code
   is removed, we may leak xfrm_dst entries as they are
   neither cached nor tracked somewhere. Fix this by
   reusing the 'uncached_list' to track xfrm_dst entries
   too. From Xin Long.

5) Fix a rcu_read_lock/rcu_read_unlock imbalance in
   xfrm_get_tos() From Xin Long.

6) Fix an infinite loop in xfrm_get_dst_nexthop. On
   transport mode we fetch the child dst_entry after
   we continue, so this pointer is never updated.
   Fix this by fetching it before we continue.

7) Fix ESN sequence number gap after IPsec GSO packets.
    We accidentally increment the sequence number counter
    on the xfrm_state by one packet too much in the ESN
    case. Fix this by setting the sequence number to the
    correct value.

8) Reset the ethernet protocol after decapsulation only if a
   mac header was set. Otherwise it breaks configurations
   with TUN devices. From Yossi Kuperman.

9) Fix __this_cpu_read() usage in preemptible code. Use
   this_cpu_read() instead in ipcomp_alloc_tfms().
   From Greg Hackmann.

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

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-13 10:38:07 -04:00
Paolo Abeni
2f987a76a9 net: ipv6: keep sk status consistent after datagram connect failure
On unsuccesful ip6_datagram_connect(), if the failure is caused by
ip6_datagram_dst_update(), the sk peer information are cleared, but
the sk->sk_state is preserved.

If the socket was already in an established status, the overall sk
status is inconsistent and fouls later checks in datagram code.

Fix this saving the old peer information and restoring them in
case of failure. This also aligns ipv6 datagram connect() behavior
with ipv4.

v1 -> v2:
 - added missing Fixes tag

Fixes: 85cb73ff9b ("net: ipv6: reset daddr and dport in sk if connect() fails")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-12 15:10:54 -04:00
William Tu
e41c7c68ea ip6erspan: make sure enough headroom at xmit.
The patch adds skb_cow_header() to ensure enough headroom
at ip6erspan_tunnel_xmit before pushing the erspan header
to the skb.

Signed-off-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-09 13:03:57 -05:00
William Tu
d6aa71197f ip6erspan: improve error handling for erspan version number.
When users fill in incorrect erspan version number through
the struct erspan_metadata uapi, current code skips pushing
the erspan header but continue pushing the gre header, which
is incorrect.  The patch fixes it by returning error.

Signed-off-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-09 13:03:56 -05:00
William Tu
3b04caab81 ip6gre: add erspan v2 to tunnel lookup
The patch adds the erspan v2 proto in ip6gre_tunnel_lookup
so the erspan v2 tunnel can be found correctly.

Signed-off-by: William Tu <u9012063@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-09 13:03:56 -05:00
Lorenzo Bianconi
9f62c15f28 ipv6: fix access to non-linear packet in ndisc_fill_redirect_hdr_option()
Fix the following slab-out-of-bounds kasan report in
ndisc_fill_redirect_hdr_option when the incoming ipv6 packet is not
linear and the accessed data are not in the linear data region of orig_skb.

[ 1503.122508] ==================================================================
[ 1503.122832] BUG: KASAN: slab-out-of-bounds in ndisc_send_redirect+0x94e/0x990
[ 1503.123036] Read of size 1184 at addr ffff8800298ab6b0 by task netperf/1932

[ 1503.123220] CPU: 0 PID: 1932 Comm: netperf Not tainted 4.16.0-rc2+ #124
[ 1503.123347] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.10.2-2.fc27 04/01/2014
[ 1503.123527] Call Trace:
[ 1503.123579]  <IRQ>
[ 1503.123638]  print_address_description+0x6e/0x280
[ 1503.123849]  kasan_report+0x233/0x350
[ 1503.123946]  memcpy+0x1f/0x50
[ 1503.124037]  ndisc_send_redirect+0x94e/0x990
[ 1503.125150]  ip6_forward+0x1242/0x13b0
[...]
[ 1503.153890] Allocated by task 1932:
[ 1503.153982]  kasan_kmalloc+0x9f/0xd0
[ 1503.154074]  __kmalloc_track_caller+0xb5/0x160
[ 1503.154198]  __kmalloc_reserve.isra.41+0x24/0x70
[ 1503.154324]  __alloc_skb+0x130/0x3e0
[ 1503.154415]  sctp_packet_transmit+0x21a/0x1810
[ 1503.154533]  sctp_outq_flush+0xc14/0x1db0
[ 1503.154624]  sctp_do_sm+0x34e/0x2740
[ 1503.154715]  sctp_primitive_SEND+0x57/0x70
[ 1503.154807]  sctp_sendmsg+0xaa6/0x1b10
[ 1503.154897]  sock_sendmsg+0x68/0x80
[ 1503.154987]  ___sys_sendmsg+0x431/0x4b0
[ 1503.155078]  __sys_sendmsg+0xa4/0x130
[ 1503.155168]  do_syscall_64+0x171/0x3f0
[ 1503.155259]  entry_SYSCALL_64_after_hwframe+0x42/0xb7

[ 1503.155436] Freed by task 1932:
[ 1503.155527]  __kasan_slab_free+0x134/0x180
[ 1503.155618]  kfree+0xbc/0x180
[ 1503.155709]  skb_release_data+0x27f/0x2c0
[ 1503.155800]  consume_skb+0x94/0xe0
[ 1503.155889]  sctp_chunk_put+0x1aa/0x1f0
[ 1503.155979]  sctp_inq_pop+0x2f8/0x6e0
[ 1503.156070]  sctp_assoc_bh_rcv+0x6a/0x230
[ 1503.156164]  sctp_inq_push+0x117/0x150
[ 1503.156255]  sctp_backlog_rcv+0xdf/0x4a0
[ 1503.156346]  __release_sock+0x142/0x250
[ 1503.156436]  release_sock+0x80/0x180
[ 1503.156526]  sctp_sendmsg+0xbb0/0x1b10
[ 1503.156617]  sock_sendmsg+0x68/0x80
[ 1503.156708]  ___sys_sendmsg+0x431/0x4b0
[ 1503.156799]  __sys_sendmsg+0xa4/0x130
[ 1503.156889]  do_syscall_64+0x171/0x3f0
[ 1503.156980]  entry_SYSCALL_64_after_hwframe+0x42/0xb7

[ 1503.157158] The buggy address belongs to the object at ffff8800298ab600
                which belongs to the cache kmalloc-1024 of size 1024
[ 1503.157444] The buggy address is located 176 bytes inside of
                1024-byte region [ffff8800298ab600, ffff8800298aba00)
[ 1503.157702] The buggy address belongs to the page:
[ 1503.157820] page:ffffea0000a62a00 count:1 mapcount:0 mapping:0000000000000000 index:0x0 compound_mapcount: 0
[ 1503.158053] flags: 0x4000000000008100(slab|head)
[ 1503.158171] raw: 4000000000008100 0000000000000000 0000000000000000 00000001800e000e
[ 1503.158350] raw: dead000000000100 dead000000000200 ffff880036002600 0000000000000000
[ 1503.158523] page dumped because: kasan: bad access detected

[ 1503.158698] Memory state around the buggy address:
[ 1503.158816]  ffff8800298ab900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 1503.158988]  ffff8800298ab980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 1503.159165] >ffff8800298aba00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 1503.159338]                    ^
[ 1503.159436]  ffff8800298aba80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 1503.159610]  ffff8800298abb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 1503.159785] ==================================================================
[ 1503.159964] Disabling lock debugging due to kernel taint

The test scenario to trigger the issue consists of 4 devices:
- H0: data sender, connected to LAN0
- H1: data receiver, connected to LAN1
- GW0 and GW1: routers between LAN0 and LAN1. Both of them have an
  ethernet connection on LAN0 and LAN1
On H{0,1} set GW0 as default gateway while on GW0 set GW1 as next hop for
data from LAN0 to LAN1.
Moreover create an ip6ip6 tunnel between H0 and H1 and send 3 concurrent
data streams (TCP/UDP/SCTP) from H0 to H1 through ip6ip6 tunnel (send
buffer size is set to 16K). While data streams are active flush the route
cache on HA multiple times.
I have not been able to identify a given commit that introduced the issue
since, using the reproducer described above, the kasan report has been
triggered from 4.14 and I have not gone back further.

Reported-by: Jianlin Shi <jishi@redhat.com>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-09 11:16:19 -05:00
Stefano Brivio
e9fa1495d7 ipv6: Reflect MTU changes on PMTU of exceptions for MTU-less routes
Currently, administrative MTU changes on a given netdevice are
not reflected on route exceptions for MTU-less routes, with a
set PMTU value, for that device:

 # ip -6 route get 2001:db8::b
 2001:db8::b from :: dev vti_a proto kernel src 2001:db8::a metric 256 pref medium
 # ping6 -c 1 -q -s10000 2001:db8::b > /dev/null
 # ip netns exec a ip -6 route get 2001:db8::b
 2001:db8::b from :: dev vti_a src 2001:db8::a metric 0
     cache expires 571sec mtu 4926 pref medium
 # ip link set dev vti_a mtu 3000
 # ip -6 route get 2001:db8::b
 2001:db8::b from :: dev vti_a src 2001:db8::a metric 0
     cache expires 571sec mtu 4926 pref medium
 # ip link set dev vti_a mtu 9000
 # ip -6 route get 2001:db8::b
 2001:db8::b from :: dev vti_a src 2001:db8::a metric 0
     cache expires 571sec mtu 4926 pref medium

The first issue is that since commit fb56be83e4 ("net-ipv6: on
device mtu change do not add mtu to mtu-less routes") we don't
call rt6_exceptions_update_pmtu() from rt6_mtu_change_route(),
which handles administrative MTU changes, if the regular route
is MTU-less.

However, PMTU exceptions should be always updated, as long as
RTAX_MTU is not locked. Keep the check for MTU-less main route,
as introduced by that commit, but, for exceptions,
call rt6_exceptions_update_pmtu() regardless of that check.

Once that is fixed, one problem remains: MTU changes are not
reflected if the new MTU is higher than the previous one,
because rt6_exceptions_update_pmtu() doesn't allow that. We
should instead allow PMTU increase if the old PMTU matches the
local MTU, as that implies that the old MTU was the lowest in the
path, and PMTU discovery might lead to different results.

The existing check in rt6_mtu_change_route() correctly took that
case into account (for regular routes only), so factor it out
and re-use it also in rt6_exceptions_update_pmtu().

While at it, fix comments style and grammar, and try to be a bit
more descriptive.

Reported-by: Xiumei Mu <xmu@redhat.com>
Fixes: fb56be83e4 ("net-ipv6: on device mtu change do not add mtu to mtu-less routes")
Fixes: f5bbe7ee79 ("ipv6: prepare rt6_mtu_change() for exception table")
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-07 13:17:50 -05:00
Yossi Kuperman
87cdf3148b xfrm: Verify MAC header exists before overwriting eth_hdr(skb)->h_proto
Artem Savkov reported that commit 5efec5c655 leads to a packet loss under
IPSec configuration. It appears that his setup consists of a TUN device,
which does not have a MAC header.

Make sure MAC header exists.

Note: TUN device sets a MAC header pointer, although it does not have one.

Fixes: 5efec5c655 ("xfrm: Fix eth_hdr(skb)->h_proto to reflect inner IP version")
Reported-by: Artem Savkov <artem.savkov@gmail.com>
Tested-by: Artem Savkov <artem.savkov@gmail.com>
Signed-off-by: Yossi Kuperman <yossiku@mellanox.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2018-03-07 10:54:29 +01:00
Daniel Axtens
80f5974d15 net: xfrm: use skb_gso_validate_network_len() to check gso sizes
Replace skb_gso_network_seglen() with
skb_gso_validate_network_len(), as it considers the GSO_BY_FRAGS
case.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-04 17:49:17 -05:00