Commit graph

9285 commits

Author SHA1 Message Date
Shmulik Ladkani
3f611a4799 ipv4: ip_do_fragment: Preserve skb_iif during fragmentation
[ Upstream commit d2f0c961148f65bc73eda72b9fa3a4e80973cb49 ]

Previously, during fragmentation after forwarding, skb->skb_iif isn't
preserved, i.e. 'ip_copy_metadata' does not copy skb_iif from given
'from' skb.

As a result, ip_do_fragment's creates fragments with zero skb_iif,
leading to inconsistent behavior.

Assume for example an eBPF program attached at tc egress (post
forwarding) that examines __sk_buff->ingress_ifindex:
 - the correct iif is observed if forwarding path does not involve
   fragmentation/refragmentation
 - a bogus iif is observed if forwarding path involves
   fragmentation/refragmentatiom

Fix, by preserving skb_iif during 'ip_copy_metadata'.

Signed-off-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-05 14:42:36 +02:00
ZhangXiaoxu
250e51f856 ipv4: set the tcp_min_rtt_wlen range from 0 to one day
[ Upstream commit 19fad20d15a6494f47f85d869f00b11343ee5c78 ]

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

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

Fixes: f672258391 ("tcp: track min RTT using windowed min-filter")
Signed-off-by: ZhangXiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-02 09:58:59 +02:00
Eric Dumazet
07445fea95 ipv4: add sanity checks in ipv4_link_failure()
[ Upstream commit 20ff83f10f113c88d0bb74589389b05250994c16 ]

Before calling __ip_options_compile(), we need to ensure the network
header is a an IPv4 one, and that it is already pulled in skb->head.

RAW sockets going through a tunnel can end up calling ipv4_link_failure()
with total garbage in the skb, or arbitrary lengthes.

syzbot report :

BUG: KASAN: stack-out-of-bounds in memcpy include/linux/string.h:355 [inline]
BUG: KASAN: stack-out-of-bounds in __ip_options_echo+0x294/0x1120 net/ipv4/ip_options.c:123
Write of size 69 at addr ffff888096abf068 by task syz-executor.4/9204

CPU: 0 PID: 9204 Comm: syz-executor.4 Not tainted 5.1.0-rc5+ #77
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+0x172/0x1f0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 check_memory_region_inline mm/kasan/generic.c:185 [inline]
 check_memory_region+0x123/0x190 mm/kasan/generic.c:191
 memcpy+0x38/0x50 mm/kasan/common.c:133
 memcpy include/linux/string.h:355 [inline]
 __ip_options_echo+0x294/0x1120 net/ipv4/ip_options.c:123
 __icmp_send+0x725/0x1400 net/ipv4/icmp.c:695
 ipv4_link_failure+0x29f/0x550 net/ipv4/route.c:1204
 dst_link_failure include/net/dst.h:427 [inline]
 vti6_xmit net/ipv6/ip6_vti.c:514 [inline]
 vti6_tnl_xmit+0x10d4/0x1c0c net/ipv6/ip6_vti.c:553
 __netdev_start_xmit include/linux/netdevice.h:4414 [inline]
 netdev_start_xmit include/linux/netdevice.h:4423 [inline]
 xmit_one net/core/dev.c:3292 [inline]
 dev_hard_start_xmit+0x1b2/0x980 net/core/dev.c:3308
 __dev_queue_xmit+0x271d/0x3060 net/core/dev.c:3878
 dev_queue_xmit+0x18/0x20 net/core/dev.c:3911
 neigh_direct_output+0x16/0x20 net/core/neighbour.c:1527
 neigh_output include/net/neighbour.h:508 [inline]
 ip_finish_output2+0x949/0x1740 net/ipv4/ip_output.c:229
 ip_finish_output+0x73c/0xd50 net/ipv4/ip_output.c:317
 NF_HOOK_COND include/linux/netfilter.h:278 [inline]
 ip_output+0x21f/0x670 net/ipv4/ip_output.c:405
 dst_output include/net/dst.h:444 [inline]
 NF_HOOK include/linux/netfilter.h:289 [inline]
 raw_send_hdrinc net/ipv4/raw.c:432 [inline]
 raw_sendmsg+0x1d2b/0x2f20 net/ipv4/raw.c:663
 inet_sendmsg+0x147/0x5d0 net/ipv4/af_inet.c:798
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0xdd/0x130 net/socket.c:661
 sock_write_iter+0x27c/0x3e0 net/socket.c:988
 call_write_iter include/linux/fs.h:1866 [inline]
 new_sync_write+0x4c7/0x760 fs/read_write.c:474
 __vfs_write+0xe4/0x110 fs/read_write.c:487
 vfs_write+0x20c/0x580 fs/read_write.c:549
 ksys_write+0x14f/0x2d0 fs/read_write.c:599
 __do_sys_write fs/read_write.c:611 [inline]
 __se_sys_write fs/read_write.c:608 [inline]
 __x64_sys_write+0x73/0xb0 fs/read_write.c:608
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x458c29
Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f293b44bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458c29
RDX: 0000000000000014 RSI: 00000000200002c0 RDI: 0000000000000003
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f293b44c6d4
R13: 00000000004c8623 R14: 00000000004ded68 R15: 00000000ffffffff

The buggy address belongs to the page:
page:ffffea00025aafc0 count:0 mapcount:0 mapping:0000000000000000 index:0x0
flags: 0x1fffc0000000000()
raw: 01fffc0000000000 0000000000000000 ffffffff025a0101 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888096abef80: 00 00 00 f2 f2 f2 f2 f2 00 00 00 00 00 00 00 f2
 ffff888096abf000: f2 f2 f2 f2 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888096abf080: 00 00 f3 f3 f3 f3 00 00 00 00 00 00 00 00 00 00
                         ^
 ffff888096abf100: 00 00 00 00 f1 f1 f1 f1 00 00 f3 f3 00 00 00 00
 ffff888096abf180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

Fixes: ed0de45a1008 ("ipv4: recompile ip options in ipv4_link_failure")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Stephen Suryaputra <ssuryaextr@gmail.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-02 09:58:59 +02:00
Peter Oskolkov
702ddf862d net: IP defrag: encapsulate rbtree defrag code into callable functions
[ Upstream commit c23f35d19db3b36ffb9e04b08f1d91565d15f84f ]

This is a refactoring patch: without changing runtime behavior,
it moves rbtree-related code from IPv4-specific files/functions
into .h/.c defrag files shared with IPv6 defragmentation code.

v2: make handling of overlapping packets match upstream.

Signed-off-by: Peter Oskolkov <posk@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-27 09:36:33 +02:00
Eric Dumazet
7ba5ec69e1 ipv4: ensure rcu_read_lock() in ipv4_link_failure()
[ Upstream commit c543cb4a5f07e09237ec0fc2c60c9f131b2c79ad ]

fib_compute_spec_dst() needs to be called under rcu protection.

syzbot reported :

WARNING: suspicious RCU usage
5.1.0-rc4+ #165 Not tainted
include/linux/inetdevice.h:220 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
1 lock held by swapper/0/0:
 #0: 0000000051b67925 ((&n->timer)){+.-.}, at: lockdep_copy_map include/linux/lockdep.h:170 [inline]
 #0: 0000000051b67925 ((&n->timer)){+.-.}, at: call_timer_fn+0xda/0x720 kernel/time/timer.c:1315

stack backtrace:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.1.0-rc4+ #165
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 lockdep_rcu_suspicious+0x153/0x15d kernel/locking/lockdep.c:5162
 __in_dev_get_rcu include/linux/inetdevice.h:220 [inline]
 fib_compute_spec_dst+0xbbd/0x1030 net/ipv4/fib_frontend.c:294
 spec_dst_fill net/ipv4/ip_options.c:245 [inline]
 __ip_options_compile+0x15a7/0x1a10 net/ipv4/ip_options.c:343
 ipv4_link_failure+0x172/0x400 net/ipv4/route.c:1195
 dst_link_failure include/net/dst.h:427 [inline]
 arp_error_report+0xd1/0x1c0 net/ipv4/arp.c:297
 neigh_invalidate+0x24b/0x570 net/core/neighbour.c:995
 neigh_timer_handler+0xc35/0xf30 net/core/neighbour.c:1081
 call_timer_fn+0x190/0x720 kernel/time/timer.c:1325
 expire_timers kernel/time/timer.c:1362 [inline]
 __run_timers kernel/time/timer.c:1681 [inline]
 __run_timers kernel/time/timer.c:1649 [inline]
 run_timer_softirq+0x652/0x1700 kernel/time/timer.c:1694
 __do_softirq+0x266/0x95a kernel/softirq.c:293
 invoke_softirq kernel/softirq.c:374 [inline]
 irq_exit+0x180/0x1d0 kernel/softirq.c:414
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0x14a/0x570 arch/x86/kernel/apic/apic.c:1062
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:807

Fixes: ed0de45a1008 ("ipv4: recompile ip options in ipv4_link_failure")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Stephen Suryaputra <ssuryaextr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-27 09:36:31 +02:00
Stephen Suryaputra
8a430e56a6 ipv4: recompile ip options in ipv4_link_failure
[ Upstream commit ed0de45a1008991fdaa27a0152befcb74d126a8b ]

Recompile IP options since IPCB may not be valid anymore when
ipv4_link_failure is called from arp_error_report.

Refer to the commit 3da1ed7ac398 ("net: avoid use IPCB in cipso_v4_error")
and the commit before that (9ef6b42ad6fd) for a similar issue.

Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-27 09:36:31 +02:00
Eric Dumazet
6728c6174a tcp: tcp_grow_window() needs to respect tcp_space()
[ Upstream commit 50ce163a72d817a99e8974222dcf2886d5deb1ae ]

For some reason, tcp_grow_window() correctly tests if enough room
is present before attempting to increase tp->rcv_ssthresh,
but does not prevent it to grow past tcp_space()

This is causing hard to debug issues, like failing
the (__tcp_select_window(sk) >= tp->rcv_wnd) test
in __tcp_ack_snd_check(), causing ACK delays and possibly
slow flows.

Depending on tcp_rmem[2], MTU, skb->len/skb->truesize ratio,
we can see the problem happening on "netperf -t TCP_RR -- -r 2000,2000"
after about 60 round trips, when the active side no longer sends
immediate acks.

This bug predates git history.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Wei Wang <weiwan@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-27 09:36:31 +02:00
Lorenzo Bianconi
1cd8788368 net: fou: do not use guehdr after iptunnel_pull_offloads in gue_udp_recv
[ Upstream commit 988dc4a9a3b66be75b30405a5494faf0dc7cffb6 ]

gue tunnels run iptunnel_pull_offloads on received skbs. This can
determine a possible use-after-free accessing guehdr pointer since
the packet will be 'uncloned' running pskb_expand_head if it is a
cloned gso skb (e.g if the packet has been sent though a veth device)

Fixes: a09a4c8dd1 ("tunnels: Remove encapsulation offloads on decap")
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-27 09:36:31 +02:00
Lorenzo Bianconi
5c6f2f4c0e net: ip_gre: fix possible use-after-free in erspan_rcv
[ Upstream commit 492b67e28ee5f2a2522fb72e3d3bcb990e461514 ]

erspan tunnels run __iptunnel_pull_header on received skbs to remove
gre and erspan headers. This can determine a possible use-after-free
accessing pkt_md pointer in erspan_rcv since the packet will be 'uncloned'
running pskb_expand_head if it is a cloned gso skb (e.g if the packet has
been sent though a veth device). Fix it resetting pkt_md pointer after
__iptunnel_pull_header

Fixes: 1d7e2ed22f ("net: erspan: refactor existing erspan code")
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-17 08:38:43 +02:00
Stephen Suryaputra
0516ef27dd vrf: check accept_source_route on the original netdevice
[ Upstream commit 8c83f2df9c6578ea4c5b940d8238ad8a41b87e9e ]

Configuration check to accept source route IP options should be made on
the incoming netdevice when the skb->dev is an l3mdev master. The route
lookup for the source route next hop also needs the incoming netdev.

v2->v3:
- Simplify by passing the original netdevice down the stack (per David
  Ahern).

Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-17 08:38:42 +02:00
Dust Li
7243e35209 tcp: fix a potential NULL pointer dereference in tcp_sk_exit
[ Upstream commit b506bc975f60f06e13e74adb35e708a23dc4e87c ]

 When tcp_sk_init() failed in inet_ctl_sock_create(),
 'net->ipv4.tcp_congestion_control' will be left
 uninitialized, but tcp_sk_exit() hasn't check for
 that.

 This patch add checking on 'net->ipv4.tcp_congestion_control'
 in tcp_sk_exit() to prevent NULL-ptr dereference.

Fixes: 6670e15244 ("tcp: Namespace-ify sysctl_tcp_default_congestion_control")
Signed-off-by: Dust Li <dust.li@linux.alibaba.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-17 08:38:41 +02:00
Koen De Schepper
0e0afb06e1 tcp: Ensure DCTCP reacts to losses
[ Upstream commit aecfde23108b8e637d9f5c5e523b24fb97035dc3 ]

RFC8257 §3.5 explicitly states that "A DCTCP sender MUST react to
loss episodes in the same way as conventional TCP".

Currently, Linux DCTCP performs no cwnd reduction when losses
are encountered. Optionally, the dctcp_clamp_alpha_on_loss resets
alpha to its maximal value if a RTO happens. This behavior
is sub-optimal for at least two reasons: i) it ignores losses
triggering fast retransmissions; and ii) it causes unnecessary large
cwnd reduction in the future if the loss was isolated as it resets
the historical term of DCTCP's alpha EWMA to its maximal value (i.e.,
denoting a total congestion). The second reason has an especially
noticeable effect when using DCTCP in high BDP environments, where
alpha normally stays at low values.

This patch replace the clamping of alpha by setting ssthresh to
half of cwnd for both fast retransmissions and RTOs, at most once
per RTT. Consequently, the dctcp_clamp_alpha_on_loss module parameter
has been removed.

The table below shows experimental results where we measured the
drop probability of a PIE AQM (not applying ECN marks) at a
bottleneck in the presence of a single TCP flow with either the
alpha-clamping option enabled or the cwnd halving proposed by this
patch. Results using reno or cubic are given for comparison.

                          |  Link   |   RTT    |    Drop
                 TCP CC   |  speed  | base+AQM | probability
        ==================|=========|==========|============
                    CUBIC |  40Mbps |  7+20ms  |    0.21%
                     RENO |         |          |    0.19%
        DCTCP-CLAMP-ALPHA |         |          |   25.80%
         DCTCP-HALVE-CWND |         |          |    0.22%
        ------------------|---------|----------|------------
                    CUBIC | 100Mbps |  7+20ms  |    0.03%
                     RENO |         |          |    0.02%
        DCTCP-CLAMP-ALPHA |         |          |   23.30%
         DCTCP-HALVE-CWND |         |          |    0.04%
        ------------------|---------|----------|------------
                    CUBIC | 800Mbps |   1+1ms  |    0.04%
                     RENO |         |          |    0.05%
        DCTCP-CLAMP-ALPHA |         |          |   18.70%
         DCTCP-HALVE-CWND |         |          |    0.06%

We see that, without halving its cwnd for all source of losses,
DCTCP drives the AQM to large drop probabilities in order to keep
the queue length under control (i.e., it repeatedly faces RTOs).
Instead, if DCTCP reacts to all source of losses, it can then be
controlled by the AQM using similar drop levels than cubic or reno.

Signed-off-by: Koen De Schepper <koen.de_schepper@nokia-bell-labs.com>
Signed-off-by: Olivier Tilmans <olivier.tilmans@nokia-bell-labs.com>
Cc: Bob Briscoe <research@bobbriscoe.net>
Cc: Lawrence Brakmo <brakmo@fb.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: Daniel Borkmann <borkmann@iogearbox.net>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Andrew Shewmaker <agshew@gmail.com>
Cc: Glenn Judd <glenn.judd@morganstanley.com>
Acked-by: Florian Westphal <fw@strlen.de>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-17 08:38:41 +02:00
Anders Roxell
0d98ecb141 netfilter: ipt_CLUSTERIP: fix warning unused variable cn
commit 206b8cc514d7ff2b79dd2d5ad939adc7c493f07a upstream.

When CONFIG_PROC_FS isn't set the variable cn isn't used.

net/ipv4/netfilter/ipt_CLUSTERIP.c: In function ‘clusterip_net_exit’:
net/ipv4/netfilter/ipt_CLUSTERIP.c:849:24: warning: unused variable ‘cn’ [-Wunused-variable]
  struct clusterip_net *cn = clusterip_pernet(net);
                        ^~

Rework so the variable 'cn' is declared inside "#ifdef CONFIG_PROC_FS".

Fixes: b12f7bad5ad3 ("netfilter: ipt_CLUSTERIP: remove wrong WARN_ON_ONCE in netns exit routine")
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-23 20:09:57 +01:00
Martin Willi
b92eaed36c esp: Skip TX bytes accounting when sending from a request socket
[ Upstream commit 09db51241118aeb06e1c8cd393b45879ce099b36 ]

On ESP output, sk_wmem_alloc is incremented for the added padding if a
socket is associated to the skb. When replying with TCP SYNACKs over
IPsec, the associated sk is a casted request socket, only. Increasing
sk_wmem_alloc on a request socket results in a write at an arbitrary
struct offset. In the best case, this produces the following WARNING:

WARNING: CPU: 1 PID: 0 at lib/refcount.c:102 esp_output_head+0x2e4/0x308 [esp4]
refcount_t: addition on 0; use-after-free.
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.0.0-rc3 #2
Hardware name: Marvell Armada 380/385 (Device Tree)
[...]
[<bf0ff354>] (esp_output_head [esp4]) from [<bf1006a4>] (esp_output+0xb8/0x180 [esp4])
[<bf1006a4>] (esp_output [esp4]) from [<c05dee64>] (xfrm_output_resume+0x558/0x664)
[<c05dee64>] (xfrm_output_resume) from [<c05d07b0>] (xfrm4_output+0x44/0xc4)
[<c05d07b0>] (xfrm4_output) from [<c05956bc>] (tcp_v4_send_synack+0xa8/0xe8)
[<c05956bc>] (tcp_v4_send_synack) from [<c0586ad8>] (tcp_conn_request+0x7f4/0x948)
[<c0586ad8>] (tcp_conn_request) from [<c058c404>] (tcp_rcv_state_process+0x2a0/0xe64)
[<c058c404>] (tcp_rcv_state_process) from [<c05958ac>] (tcp_v4_do_rcv+0xf0/0x1f4)
[<c05958ac>] (tcp_v4_do_rcv) from [<c0598a4c>] (tcp_v4_rcv+0xdb8/0xe20)
[<c0598a4c>] (tcp_v4_rcv) from [<c056eb74>] (ip_protocol_deliver_rcu+0x2c/0x2dc)
[<c056eb74>] (ip_protocol_deliver_rcu) from [<c056ee6c>] (ip_local_deliver_finish+0x48/0x54)
[<c056ee6c>] (ip_local_deliver_finish) from [<c056eecc>] (ip_local_deliver+0x54/0xec)
[<c056eecc>] (ip_local_deliver) from [<c056efac>] (ip_rcv+0x48/0xb8)
[<c056efac>] (ip_rcv) from [<c0519c2c>] (__netif_receive_skb_one_core+0x50/0x6c)
[...]

The issue triggers only when not using TCP syncookies, as for syncookies
no socket is associated.

Fixes: cac2661c53 ("esp4: Avoid skb_cow_data whenever possible")
Fixes: 03e2a30f6a ("esp6: Avoid skb_cow_data whenever possible")
Signed-off-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-23 20:09:48 +01:00
Guillaume Nault
173e9023a0 tcp: handle inet_csk_reqsk_queue_add() failures
[  Upstream commit 9d3e1368bb45893a75a5dfb7cd21fdebfa6b47af ]

Commit 7716682cc5 ("tcp/dccp: fix another race at listener
dismantle") let inet_csk_reqsk_queue_add() fail, and adjusted
{tcp,dccp}_check_req() accordingly. However, TFO and syncookies
weren't modified, thus leaking allocated resources on error.

Contrary to tcp_check_req(), in both syncookies and TFO cases,
we need to drop the request socket. Also, since the child socket is
created with inet_csk_clone_lock(), we have to unlock it and drop an
extra reference (->sk_refcount is initially set to 2 and
inet_csk_reqsk_queue_add() drops only one ref).

For TFO, we also need to revert the work done by tcp_try_fastopen()
(with reqsk_fastopen_remove()).

Fixes: 7716682cc5 ("tcp/dccp: fix another race at listener dismantle")
Signed-off-by: Guillaume Nault <gnault@redhat.com>
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>
2019-03-19 13:12:39 +01:00
Christoph Paasch
fba43f49fd tcp: Don't access TCP_SKB_CB before initializing it
[ Upstream commit f2feaefdabb0a6253aa020f65e7388f07a9ed47c ]

Since commit eeea10b83a ("tcp: add
tcp_v4_fill_cb()/tcp_v4_restore_cb()"), tcp_vX_fill_cb is only called
after tcp_filter(). That means, TCP_SKB_CB(skb)->end_seq still points to
the IP-part of the cb.

We thus should not mock with it, as this can trigger bugs (thanks
syzkaller):
[   12.349396] ==================================================================
[   12.350188] BUG: KASAN: slab-out-of-bounds in ip6_datagram_recv_specific_ctl+0x19b3/0x1a20
[   12.351035] Read of size 1 at addr ffff88006adbc208 by task test_ip6_datagr/1799

Setting end_seq is actually no more necessary in tcp_filter as it gets
initialized later on in tcp_vX_fill_cb.

Cc: Eric Dumazet <edumazet@google.com>
Fixes: eeea10b83a ("tcp: add tcp_v4_fill_cb()/tcp_v4_restore_cb()")
Signed-off-by: Christoph Paasch <cpaasch@apple.com>
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>
2019-03-19 13:12:39 +01:00
Soheil Hassas Yeganeh
8accd04eb9 tcp: do not report TCP_CM_INQ of 0 for closed connections
[ Upstream commit 6466e715651f9f358e60c5ea4880e4731325827f ]

Returning 0 as inq to userspace indicates there is no more data to
read, and the application needs to wait for EPOLLIN. For a connection
that has received FIN from the remote peer, however, the application
must continue reading until getting EOF (return value of 0
from tcp_recvmsg) or an error, if edge-triggered epoll (EPOLLET) is
being used. Otherwise, the application will never receive a new
EPOLLIN, since there is no epoll edge after the FIN.

Return 1 when there is no data left on the queue but the
connection has received FIN, so that the applications continue
reading.

Fixes: b75eba76d3 (tcp: send in-queue bytes in cmsg upon read)
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-19 13:12:39 +01:00
Xin Long
eaa0962e1e route: set the deleted fnhe fnhe_daddr to 0 in ip_del_fnhe to fix a race
[ Upstream commit ee60ad219f5c7c4fb2f047f88037770063ef785f ]

The race occurs in __mkroute_output() when 2 threads lookup a dst:

  CPU A                 CPU B
  find_exception()
                        find_exception() [fnhe expires]
                        ip_del_fnhe() [fnhe is deleted]
  rt_bind_exception()

In rt_bind_exception() it will bind a deleted fnhe with the new dst, and
this dst will get no chance to be freed. It causes a dev defcnt leak and
consecutive dmesg warnings:

  unregister_netdevice: waiting for ethX to become free. Usage count = 1

Especially thanks Jon to identify the issue.

This patch fixes it by setting fnhe_daddr to 0 in ip_del_fnhe() to stop
binding the deleted fnhe with a new dst when checking fnhe's fnhe_daddr
and daddr in rt_bind_exception().

It works as both ip_del_fnhe() and rt_bind_exception() are protected by
fnhe_lock and the fhne is freed by kfree_rcu().

Fixes: deed49df73 ("route: check and remove route cache when we get route")
Signed-off-by: Jon Maxwell <jmaxwell37@gmail.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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-19 13:12:39 +01:00
Paolo Abeni
7760937dc2 ipv4/route: fail early when inet dev is missing
[ Upstream commit 22c74764aa2943ecdf9f07c900d8a9c8ba6c9265 ]

If a non local multicast packet reaches ip_route_input_rcu() while
the ingress device IPv4 private data (in_dev) is NULL, we end up
doing a NULL pointer dereference in IN_DEV_MFORWARD().

Since the later call to ip_route_input_mc() is going to fail if
!in_dev, we can fail early in such scenario and avoid the dangerous
code path.

v1 -> v2:
 - clarified the commit message, no code changes

Reported-by: Tianhao Zhao <tizhao@redhat.com>
Fixes: e58e415968 ("net: Enable support for VRF with ipv4 multicast")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-19 13:12:38 +01:00
Su Yanjun
8ce41db0dc vti4: Fix a ipip packet processing bug in 'IPCOMP' virtual tunnel
[ Upstream commit dd9ee3444014e8f28c0eefc9fffc9ac9c5248c12 ]

Recently we run a network test over ipcomp virtual tunnel.We find that
if a ipv4 packet needs fragment, then the peer can't receive
it.

We deep into the code and find that when packet need fragment the smaller
fragment will be encapsulated by ipip not ipcomp. So when the ipip packet
goes into xfrm, it's skb->dev is not properly set. The ipv4 reassembly code
always set skb'dev to the last fragment's dev. After ipv4 defrag processing,
when the kernel rp_filter parameter is set, the skb will be drop by -EXDEV
error.

This patch adds compatible support for the ipip process in ipcomp virtual tunnel.

Signed-off-by: Su Yanjun <suyj.fnst@cn.fujitsu.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-03-13 14:02:26 -07:00
David Ahern
cc211561d1 ipv4: Pass original device to ip_rcv_finish_core
[ Upstream commit a1fd1ad2552fad9e649eeb85fd79301e2880a886 ]

ip_route_input_rcu expects the original ingress device (e.g., for
proper multicast handling). The skb->dev can be changed by l3mdev_ip_rcv,
so dev needs to be saved prior to calling it. This was the behavior prior
to the listify changes.

Fixes: 5fa12739a5 ("net: ipv4: listify ip_rcv_finish")
Cc: Edward Cree <ecree@solarflare.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-10 07:17:19 +01:00
David Ahern
8c0aa3f690 ipv4: Return error for RTA_VIA attribute
[ Upstream commit b6e9e5df4ecf100f6a10ab2ade8e46d47a4b9779 ]

IPv4 currently does not support nexthops outside of the AF_INET family.
Specifically, it does not handle RTA_VIA attribute. If it is passed
in a route add request, the actual route added only uses the device
which is clearly not what the user intended:

  $ ip ro add 172.16.1.0/24 via inet6 2001:db8:1::1 dev eth0
  $ ip ro ls
  ...
  172.16.1.0/24 dev eth0

Catch this and fail the route add:
  $ ip ro add 172.16.1.0/24 via inet6 2001:db8:1::1 dev eth0
  Error: IPv4 does not support RTA_VIA attribute.

Fixes: 03c0566542 ("mpls: Netlink commands to add, remove, and dump routes")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-10 07:17:19 +01:00
Nazarov Sergey
125bc1e67e net: avoid use IPCB in cipso_v4_error
[ Upstream commit 3da1ed7ac398f34fff1694017a07054d69c5f5c5 ]

Extract IP options in cipso_v4_error and use __icmp_send.

Signed-off-by: Sergey Nazarov <s-nazarov@yandex.ru>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-10 07:17:19 +01:00
Nazarov Sergey
f2397468fb net: Add __icmp_send helper.
[ Upstream commit 9ef6b42ad6fd7929dd1b6092cb02014e382c6a91 ]

Add __icmp_send function having ip_options struct parameter

Signed-off-by: Sergey Nazarov <s-nazarov@yandex.ru>
Reviewed-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-10 07:17:19 +01:00
Paul Moore
e3713abc42 netlabel: fix out-of-bounds memory accesses
[ Upstream commit 5578de4834fe0f2a34fedc7374be691443396d1f ]

There are two array out-of-bounds memory accesses, one in
cipso_v4_map_lvl_valid(), the other in netlbl_bitmap_walk().  Both
errors are embarassingly simple, and the fixes are straightforward.

As a FYI for anyone backporting this patch to kernels prior to v4.8,
you'll want to apply the netlbl_bitmap_walk() patch to
cipso_v4_bitmap_walk() as netlbl_bitmap_walk() doesn't exist before
Linux v4.8.

Reported-by: Jann Horn <jannh@google.com>
Fixes: 446fda4f26 ("[NetLabel]: CIPSOv4 engine")
Fixes: 3faa8f982f ("netlabel: Move bitmap manipulation functions to the NetLabel core.")
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-10 07:17:18 +01:00
Hangbin Liu
99ed945821 ipv4: Add ICMPv6 support when parse route ipproto
[ Upstream commit 5e1a99eae84999a2536f50a0beaf5d5262337f40 ]

For ip rules, we need to use 'ipproto ipv6-icmp' to match ICMPv6 headers.
But for ip -6 route, currently we only support tcp, udp and icmp.

Add ICMPv6 support so we can match ipv6-icmp rules for route lookup.

v2: As David Ahern and Sabrina Dubroca suggested, Add an argument to
rtm_getroute_parse_ip_proto() to handle ICMP/ICMPv6 with different family.

Reported-by: Jianlin Shi <jishi@redhat.com>
Fixes: eacb9384a3 ("ipv6: support sport, dport and ip_proto in RTM_GETROUTE")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-10 07:17:17 +01:00
Taehee Yoo
6546e1150c netfilter: ipt_CLUSTERIP: fix sleep-in-atomic bug in clusterip_config_entry_put()
commit 2a61d8b883bbad26b06d2e6cc3777a697e78830d upstream.

A proc_remove() can sleep. so that it can't be inside of spin_lock.
Hence proc_remove() is moved to outside of spin_lock. and it also
adds mutex to sync create and remove of proc entry(config->pde).

test commands:
SHELL#1
   %while :; do iptables -A INPUT -p udp -i enp2s0 -d 192.168.1.100 \
	   --dport 9000  -j CLUSTERIP --new --hashmode sourceip \
	   --clustermac 01:00:5e:00:00:21 --total-nodes 3 --local-node 3; \
	   iptables -F; done

SHELL#2
   %while :; do echo +1 > /proc/net/ipt_CLUSTERIP/192.168.1.100; \
	   echo -1 > /proc/net/ipt_CLUSTERIP/192.168.1.100; done

[ 2949.569864] BUG: sleeping function called from invalid context at kernel/sched/completion.c:99
[ 2949.579944] in_atomic(): 1, irqs_disabled(): 0, pid: 5472, name: iptables
[ 2949.587920] 1 lock held by iptables/5472:
[ 2949.592711]  #0: 000000008f0ebcf2 (&(&cn->lock)->rlock){+...}, at: refcount_dec_and_lock+0x24/0x50
[ 2949.603307] CPU: 1 PID: 5472 Comm: iptables Tainted: G        W         4.19.0-rc5+ #16
[ 2949.604212] Hardware name: To be filled by O.E.M. To be filled by O.E.M./Aptio CRB, BIOS 5.6.5 07/08/2015
[ 2949.604212] Call Trace:
[ 2949.604212]  dump_stack+0xc9/0x16b
[ 2949.604212]  ? show_regs_print_info+0x5/0x5
[ 2949.604212]  ___might_sleep+0x2eb/0x420
[ 2949.604212]  ? set_rq_offline.part.87+0x140/0x140
[ 2949.604212]  ? _rcu_barrier_trace+0x400/0x400
[ 2949.604212]  wait_for_completion+0x94/0x710
[ 2949.604212]  ? wait_for_completion_interruptible+0x780/0x780
[ 2949.604212]  ? __kernel_text_address+0xe/0x30
[ 2949.604212]  ? __lockdep_init_map+0x10e/0x5c0
[ 2949.604212]  ? __lockdep_init_map+0x10e/0x5c0
[ 2949.604212]  ? __init_waitqueue_head+0x86/0x130
[ 2949.604212]  ? init_wait_entry+0x1a0/0x1a0
[ 2949.604212]  proc_entry_rundown+0x208/0x270
[ 2949.604212]  ? proc_reg_get_unmapped_area+0x370/0x370
[ 2949.604212]  ? __lock_acquire+0x4500/0x4500
[ 2949.604212]  ? complete+0x18/0x70
[ 2949.604212]  remove_proc_subtree+0x143/0x2a0
[ 2949.708655]  ? remove_proc_entry+0x390/0x390
[ 2949.708655]  clusterip_tg_destroy+0x27a/0x630 [ipt_CLUSTERIP]
[ ... ]

Fixes: b3e456fce9 ("netfilter: ipt_CLUSTERIP: fix a race condition of proc file creation")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-27 10:09:03 +01:00
Konstantin Khlebnikov
589503cb24 inet_diag: fix reporting cgroup classid and fallback to priority
[ Upstream commit 1ec17dbd90f8b638f41ee650558609c1af63dfa0 ]

Field idiag_ext in struct inet_diag_req_v2 used as bitmap of requested
extensions has only 8 bits. Thus extensions starting from DCTCPINFO
cannot be requested directly. Some of them included into response
unconditionally or hook into some of lower 8 bits.

Extension INET_DIAG_CLASS_ID has not way to request from the beginning.

This patch bundle it with INET_DIAG_TCLASS (ipv6 tos), fixes space
reservation, and documents behavior for other extensions.

Also this patch adds fallback to reporting socket priority. This filed
is more widely used for traffic classification because ipv4 sockets
automatically maps TOS to priority and default qdisc pfifo_fast knows
about that. But priority could be changed via setsockopt SO_PRIORITY so
INET_DIAG_TOS isn't enough for predicting class.

Also cgroup2 obsoletes net_cls classid (it always zero), but we cannot
reuse this field for reporting cgroup2 id because it is 64-bit (ino+gen).

So, after this patch INET_DIAG_CLASS_ID will report socket priority
for most common setup when net_cls isn't set and/or cgroup2 in use.

Fixes: 0888e372c3 ("net: inet: diag: expose sockets cgroup classid")
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-27 10:08:58 +01:00
Jann Horn
6a3f723787 netfilter: nf_nat_snmp_basic: add missing length checks in ASN.1 cbs
commit c4c07b4d6fa1f11880eab8e076d3d060ef3f55fc upstream.

The generic ASN.1 decoder infrastructure doesn't guarantee that callbacks
will get as much data as they expect; callbacks have to check the `datalen`
parameter before looking at `data`. Make sure that snmp_version() and
snmp_helper() don't read/write beyond the end of the packet data.

(Also move the assignment to `pdata` down below the check to make it clear
that it isn't necessarily a pointer we can use before the `datalen` check.)

Fixes: cc2d58634e ("netfilter: nf_nat_snmp_basic: use asn1 decoder library")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-23 09:07:27 +01:00
Eric Dumazet
1bdb1675f3 tcp: tcp_v4_err() should be more careful
[ Upstream commit 2c4cc9712364c051b1de2d175d5fbea6be948ebf ]

ICMP handlers are not very often stressed, we should
make them more resilient to bugs that might surface in
the future.

If there is no packet in retransmit queue, we should
avoid a NULL deref.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: soukjin bae <soukjin.bae@samsung.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-23 09:07:26 +01:00
Eric Dumazet
df1b583c16 tcp: clear icsk_backoff in tcp_write_queue_purge()
[ Upstream commit 04c03114be82194d4a4858d41dba8e286ad1787c ]

soukjin bae reported a crash in tcp_v4_err() handling
ICMP_DEST_UNREACH after tcp_write_queue_head(sk)
returned a NULL pointer.

Current logic should have prevented this :

  if (seq != tp->snd_una  || !icsk->icsk_retransmits ||
      !icsk->icsk_backoff || fastopen)
      break;

Problem is the write queue might have been purged
and icsk_backoff has not been cleared.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: soukjin bae <soukjin.bae@samsung.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-23 09:07:26 +01:00
Lorenzo Bianconi
1764111c99 net: ipv4: use a dedicated counter for icmp_v4 redirect packets
[ Upstream commit c09551c6ff7fe16a79a42133bcecba5fc2fc3291 ]

According to the algorithm described in the comment block at the
beginning of ip_rt_send_redirect, the host should try to send
'ip_rt_redirect_number' ICMP redirect packets with an exponential
backoff and then stop sending them at all assuming that the destination
ignores redirects.
If the device has previously sent some ICMP error packets that are
rate-limited (e.g TTL expired) and continues to receive traffic,
the redirect packets will never be transmitted. This happens since
peer->rate_tokens will be typically greater than 'ip_rt_redirect_number'
and so it will never be reset even if the redirect silence timeout
(ip_rt_redirect_silence) has elapsed without receiving any packet
requiring redirects.

Fix it by using a dedicated counter for the number of ICMP redirect
packets that has been sent by the host

I have not been able to identify a given commit that introduced the
issue since ip_rt_send_redirect implements the same rate-limiting
algorithm from commit 1da177e4c3 ("Linux-2.6.12-rc2")

Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-02-23 09:07:24 +01:00
Lorenzo Bianconi
0a198e0bb8 net: ip_gre: use erspan key field for tunnel lookup
[ Upstream commit cb73ee40b1b381eaf3749e6dbeed567bb38e5258 ]

Use ERSPAN key header field as tunnel key in gre_parse_header routine
since ERSPAN protocol sets the key field of the external GRE header to
0 resulting in a tunnel lookup fail in ip6gre_err.
In addition remove key field parsing and pskb_may_pull check in
erspan_rcv and ip6erspan_rcv

Fixes: 5a963eb61b ("ip6_gre: Add ERSPAN native tunnel support")
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-06 17:30:06 +01:00
Lorenzo Bianconi
897ea28bd2 net: ip_gre: always reports o_key to userspace
[ Upstream commit feaf5c796b3f0240f10d0d6d0b686715fd58a05b ]

Erspan protocol (version 1 and 2) relies on o_key to configure
session id header field. However TUNNEL_KEY bit is cleared in
erspan_xmit since ERSPAN protocol does not set the key field
of the external GRE header and so the configured o_key is not reported
to userspace. The issue can be triggered with the following reproducer:

$ip link add erspan1 type erspan local 192.168.0.1 remote 192.168.0.2 \
    key 1 seq erspan_ver 1
$ip link set erspan1 up
$ip -d link sh erspan1

erspan1@NONE: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1450 qdisc pfifo_fast state UNKNOWN mode DEFAULT
  link/ether 52:aa:99:95:9a:b5 brd ff:ff:ff:ff:ff:ff promiscuity 0 minmtu 68 maxmtu 1500
  erspan remote 192.168.0.2 local 192.168.0.1 ttl inherit ikey 0.0.0.1 iseq oseq erspan_index 0

Fix the issue adding TUNNEL_KEY bit to the o_flags parameter in
ipgre_fill_info

Fixes: 84e54fe0a5 ("gre: introduce native tunnel support for ERSPAN")
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-06 17:30:06 +01:00
Greg Kroah-Hartman
8c763a3cf5 Fix "net: ipv4: do not handle duplicate fragments as overlapping"
ade446403bfb ("net: ipv4: do not handle duplicate fragments as
overlapping") was backported to many stable trees, but it had a problem
that was "accidentally" fixed by the upstream commit 0ff89efb5246 ("ip:
fail fast on IP defrag errors")

This is the fixup for that problem as we do not want the larger patch in
the older stable trees.

Fixes: ade446403bfb ("net: ipv4: do not handle duplicate fragments as overlapping")
Reported-by: Ivan Babrou <ivan@cloudflare.com>
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-02-06 17:30:05 +01:00
Willem de Bruijn
2cade15d58 tcp: allow MSG_ZEROCOPY transmission also in CLOSE_WAIT state
[ Upstream commit 13d7f46386e060df31b727c9975e38306fa51e7a ]

TCP transmission with MSG_ZEROCOPY fails if the peer closes its end of
the connection and so transitions this socket to CLOSE_WAIT state.

Transmission in close wait state is acceptable. Other similar tests in
the stack (e.g., in FastOpen) accept both states. Relax this test, too.

Link: https://www.mail-archive.com/netdev@vger.kernel.org/msg276886.html
Link: https://www.mail-archive.com/netdev@vger.kernel.org/msg227390.html
Fixes: f214f915e7 ("tcp: enable MSG_ZEROCOPY")
Reported-by: Marek Majkowski <marek@cloudflare.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
CC: Yuchung Cheng <ycheng@google.com>
CC: Neal Cardwell <ncardwell@google.com>
CC: Soheil Hassas Yeganeh <soheil@google.com>
CC: Alexey Kodanev <alexey.kodanev@oracle.com>
Acked-by: Soheil Hassas Yeganeh <soheil@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>
2019-01-31 08:14:33 +01:00
Xin Long
552cd931b4 erspan: build the header with the right proto according to erspan_ver
[ Upstream commit 20704bd1633dd5afb29a321d3a615c9c8e9c9d05 ]

As said in draft-foschiano-erspan-03#section4:

   Different frame variants known as "ERSPAN Types" can be
   distinguished based on the GRE "Protocol Type" field value: Type I
   and II's value is 0x88BE while Type III's is 0x22EB [ETYPES].

So set it properly in erspan_xmit() according to erspan_ver. While at
it, also remove the unused parameter 'proto' in erspan_fb_xmit().

Fixes: 94d7d8f292 ("ip6_gre: add erspan v2 support")
Reported-by: Jianlin Shi <jishi@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31 08:14:33 +01:00
Willem de Bruijn
e3fa624ee7 udp: with udp_segment release on error path
[ Upstream commit 0f149c9fec3cd720628ecde83bfc6f64c1e7dcb6 ]

Failure __ip_append_data triggers udp_flush_pending_frames, but these
tests happen later. The skb must be freed directly.

Fixes: bec1f6f697 ("udp: generate gso with UDP_SEGMENT")
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31 08:14:33 +01:00
Ido Schimmel
adbf7e5809 net: ipv4: Fix memory leak in network namespace dismantle
[ Upstream commit f97f4dd8b3bb9d0993d2491e0f22024c68109184 ]

IPv4 routing tables are flushed in two cases:

1. In response to events in the netdev and inetaddr notification chains
2. When a network namespace is being dismantled

In both cases only routes associated with a dead nexthop group are
flushed. However, a nexthop group will only be marked as dead in case it
is populated with actual nexthops using a nexthop device. This is not
the case when the route in question is an error route (e.g.,
'blackhole', 'unreachable').

Therefore, when a network namespace is being dismantled such routes are
not flushed and leaked [1].

To reproduce:
# ip netns add blue
# ip -n blue route add unreachable 192.0.2.0/24
# ip netns del blue

Fix this by not skipping error routes that are not marked with
RTNH_F_DEAD when flushing the routing tables.

To prevent the flushing of such routes in case #1, add a parameter to
fib_table_flush() that indicates if the table is flushed as part of
namespace dismantle or not.

Note that this problem does not exist in IPv6 since error routes are
associated with the loopback device.

[1]
unreferenced object 0xffff888066650338 (size 56):
  comm "ip", pid 1206, jiffies 4294786063 (age 26.235s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 b0 1c 62 61 80 88 ff ff  ..........ba....
    e8 8b a1 64 80 88 ff ff 00 07 00 08 fe 00 00 00  ...d............
  backtrace:
    [<00000000856ed27d>] inet_rtm_newroute+0x129/0x220
    [<00000000fcdfc00a>] rtnetlink_rcv_msg+0x397/0xa20
    [<00000000cb85801a>] netlink_rcv_skb+0x132/0x380
    [<00000000ebc991d2>] netlink_unicast+0x4c0/0x690
    [<0000000014f62875>] netlink_sendmsg+0x929/0xe10
    [<00000000bac9d967>] sock_sendmsg+0xc8/0x110
    [<00000000223e6485>] ___sys_sendmsg+0x77a/0x8f0
    [<000000002e94f880>] __sys_sendmsg+0xf7/0x250
    [<00000000ccb1fa72>] do_syscall_64+0x14d/0x610
    [<00000000ffbe3dae>] entry_SYSCALL_64_after_hwframe+0x49/0xbe
    [<000000003a8b605b>] 0xffffffffffffffff
unreferenced object 0xffff888061621c88 (size 48):
  comm "ip", pid 1206, jiffies 4294786063 (age 26.235s)
  hex dump (first 32 bytes):
    6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b  kkkkkkkkkkkkkkkk
    6b 6b 6b 6b 6b 6b 6b 6b d8 8e 26 5f 80 88 ff ff  kkkkkkkk..&_....
  backtrace:
    [<00000000733609e3>] fib_table_insert+0x978/0x1500
    [<00000000856ed27d>] inet_rtm_newroute+0x129/0x220
    [<00000000fcdfc00a>] rtnetlink_rcv_msg+0x397/0xa20
    [<00000000cb85801a>] netlink_rcv_skb+0x132/0x380
    [<00000000ebc991d2>] netlink_unicast+0x4c0/0x690
    [<0000000014f62875>] netlink_sendmsg+0x929/0xe10
    [<00000000bac9d967>] sock_sendmsg+0xc8/0x110
    [<00000000223e6485>] ___sys_sendmsg+0x77a/0x8f0
    [<000000002e94f880>] __sys_sendmsg+0xf7/0x250
    [<00000000ccb1fa72>] do_syscall_64+0x14d/0x610
    [<00000000ffbe3dae>] entry_SYSCALL_64_after_hwframe+0x49/0xbe
    [<000000003a8b605b>] 0xffffffffffffffff

Fixes: 8cced9eff1 ("[NETNS]: Enable routing configuration in non-initial namespace.")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31 08:14:32 +01:00
Ross Lagerwall
40f2f08030 net: Fix usage of pskb_trim_rcsum
[ Upstream commit 6c57f0458022298e4da1729c67bd33ce41c14e7a ]

In certain cases, pskb_trim_rcsum() may change skb pointers.
Reinitialize header pointers afterwards to avoid potential
use-after-frees. Add a note in the documentation of
pskb_trim_rcsum(). Found by KASAN.

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-31 08:14:31 +01:00
Taehee Yoo
9d51378a68 netfilter: ipt_CLUSTERIP: fix deadlock in netns exit routine
[ Upstream commit 5a86d68bcf02f2d1e9a5897dd482079fd5f75e7f ]

When network namespace is destroyed, cleanup_net() is called.
cleanup_net() holds pernet_ops_rwsem then calls each ->exit callback.
So that clusterip_tg_destroy() is called by cleanup_net().
And clusterip_tg_destroy() calls unregister_netdevice_notifier().

But both cleanup_net() and clusterip_tg_destroy() hold same
lock(pernet_ops_rwsem). hence deadlock occurrs.

After this patch, only 1 notifier is registered when module is inserted.
And all of configs are added to per-net list.

test commands:
   %ip netns add vm1
   %ip netns exec vm1 bash
   %ip link set lo up
   %iptables -A INPUT -p tcp -i lo -d 192.168.0.5 --dport 80 \
	-j CLUSTERIP --new --hashmode sourceip \
	--clustermac 01:00:5e:00:00:20 --total-nodes 2 --local-node 1
   %exit
   %ip netns del vm1

splat looks like:
[  341.809674] ============================================
[  341.809674] WARNING: possible recursive locking detected
[  341.809674] 4.19.0-rc5+ #16 Tainted: G        W
[  341.809674] --------------------------------------------
[  341.809674] kworker/u4:2/87 is trying to acquire lock:
[  341.809674] 000000005da2d519 (pernet_ops_rwsem){++++}, at: unregister_netdevice_notifier+0x8c/0x460
[  341.809674]
[  341.809674] but task is already holding lock:
[  341.809674] 000000005da2d519 (pernet_ops_rwsem){++++}, at: cleanup_net+0x119/0x900
[  341.809674]
[  341.809674] other info that might help us debug this:
[  341.809674]  Possible unsafe locking scenario:
[  341.809674]
[  341.809674]        CPU0
[  341.809674]        ----
[  341.809674]   lock(pernet_ops_rwsem);
[  341.809674]   lock(pernet_ops_rwsem);
[  341.809674]
[  341.809674]  *** DEADLOCK ***
[  341.809674]
[  341.809674]  May be due to missing lock nesting notation
[  341.809674]
[  341.809674] 3 locks held by kworker/u4:2/87:
[  341.809674]  #0: 00000000d9df6c92 ((wq_completion)"%s""netns"){+.+.}, at: process_one_work+0xafe/0x1de0
[  341.809674]  #1: 00000000c2cbcee2 (net_cleanup_work){+.+.}, at: process_one_work+0xb60/0x1de0
[  341.809674]  #2: 000000005da2d519 (pernet_ops_rwsem){++++}, at: cleanup_net+0x119/0x900
[  341.809674]
[  341.809674] stack backtrace:
[  341.809674] CPU: 1 PID: 87 Comm: kworker/u4:2 Tainted: G        W         4.19.0-rc5+ #16
[  341.809674] Workqueue: netns cleanup_net
[  341.809674] Call Trace:
[ ... ]
[  342.070196]  down_write+0x93/0x160
[  342.070196]  ? unregister_netdevice_notifier+0x8c/0x460
[  342.070196]  ? down_read+0x1e0/0x1e0
[  342.070196]  ? sched_clock_cpu+0x126/0x170
[  342.070196]  ? find_held_lock+0x39/0x1c0
[  342.070196]  unregister_netdevice_notifier+0x8c/0x460
[  342.070196]  ? register_netdevice_notifier+0x790/0x790
[  342.070196]  ? __local_bh_enable_ip+0xe9/0x1b0
[  342.070196]  ? __local_bh_enable_ip+0xe9/0x1b0
[  342.070196]  ? clusterip_tg_destroy+0x372/0x650 [ipt_CLUSTERIP]
[  342.070196]  ? trace_hardirqs_on+0x93/0x210
[  342.070196]  ? __bpf_trace_preemptirq_template+0x10/0x10
[  342.070196]  ? clusterip_tg_destroy+0x372/0x650 [ipt_CLUSTERIP]
[  342.123094]  clusterip_tg_destroy+0x3ad/0x650 [ipt_CLUSTERIP]
[  342.123094]  ? clusterip_net_init+0x3d0/0x3d0 [ipt_CLUSTERIP]
[  342.123094]  ? cleanup_match+0x17d/0x200 [ip_tables]
[  342.123094]  ? xt_unregister_table+0x215/0x300 [x_tables]
[  342.123094]  ? kfree+0xe2/0x2a0
[  342.123094]  cleanup_entry+0x1d5/0x2f0 [ip_tables]
[  342.123094]  ? cleanup_match+0x200/0x200 [ip_tables]
[  342.123094]  __ipt_unregister_table+0x9b/0x1a0 [ip_tables]
[  342.123094]  iptable_filter_net_exit+0x43/0x80 [iptable_filter]
[  342.123094]  ops_exit_list.isra.10+0x94/0x140
[  342.123094]  cleanup_net+0x45b/0x900
[ ... ]

Fixes: 202f59afd4 ("netfilter: ipt_CLUSTERIP: do not hold dev")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-26 09:32:40 +01:00
Taehee Yoo
bb7b6c49cc netfilter: ipt_CLUSTERIP: remove wrong WARN_ON_ONCE in netns exit routine
[ Upstream commit b12f7bad5ad3724d19754390a3e80928525c0769 ]

When network namespace is destroyed, both clusterip_tg_destroy() and
clusterip_net_exit() are called. and clusterip_net_exit() is called
before clusterip_tg_destroy().
Hence cleanup check code in clusterip_net_exit() doesn't make sense.

test commands:
   %ip netns add vm1
   %ip netns exec vm1 bash
   %ip link set lo up
   %iptables -A INPUT -p tcp -i lo -d 192.168.0.5 --dport 80 \
	-j CLUSTERIP --new --hashmode sourceip \
	--clustermac 01:00:5e:00:00:20 --total-nodes 2 --local-node 1
   %exit
   %ip netns del vm1

splat looks like:
[  341.184508] WARNING: CPU: 1 PID: 87 at net/ipv4/netfilter/ipt_CLUSTERIP.c:840 clusterip_net_exit+0x319/0x380 [ipt_CLUSTERIP]
[  341.184850] Modules linked in: ipt_CLUSTERIP nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 xt_tcpudp iptable_filter bpfilter ip_tables x_tables
[  341.184850] CPU: 1 PID: 87 Comm: kworker/u4:2 Not tainted 4.19.0-rc5+ #16
[  341.227509] Workqueue: netns cleanup_net
[  341.227509] RIP: 0010:clusterip_net_exit+0x319/0x380 [ipt_CLUSTERIP]
[  341.227509] Code: 0f 85 7f fe ff ff 48 c7 c2 80 64 2c c0 be a8 02 00 00 48 c7 c7 a0 63 2c c0 c6 05 18 6e 00 00 01 e8 bc 38 ff f5 e9 5b fe ff ff <0f> 0b e9 33 ff ff ff e8 4b 90 50 f6 e9 2d fe ff ff 48 89 df e8 de
[  341.227509] RSP: 0018:ffff88011086f408 EFLAGS: 00010202
[  341.227509] RAX: dffffc0000000000 RBX: 1ffff1002210de85 RCX: 0000000000000000
[  341.227509] RDX: 1ffff1002210de85 RSI: ffff880110813be8 RDI: ffffed002210de58
[  341.227509] RBP: ffff88011086f4d0 R08: 0000000000000000 R09: 0000000000000000
[  341.227509] R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff1002210de81
[  341.227509] R13: ffff880110625a48 R14: ffff880114cec8c8 R15: 0000000000000014
[  341.227509] FS:  0000000000000000(0000) GS:ffff880116600000(0000) knlGS:0000000000000000
[  341.227509] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  341.227509] CR2: 00007f11fd38e000 CR3: 000000013ca16000 CR4: 00000000001006e0
[  341.227509] Call Trace:
[  341.227509]  ? __clusterip_config_find+0x460/0x460 [ipt_CLUSTERIP]
[  341.227509]  ? default_device_exit+0x1ca/0x270
[  341.227509]  ? remove_proc_entry+0x1cd/0x390
[  341.227509]  ? dev_change_net_namespace+0xd00/0xd00
[  341.227509]  ? __init_waitqueue_head+0x130/0x130
[  341.227509]  ops_exit_list.isra.10+0x94/0x140
[  341.227509]  cleanup_net+0x45b/0x900
[ ... ]

Fixes: 613d0776d3 ("netfilter: exit_net cleanup check added")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-26 09:32:40 +01:00
Taehee Yoo
744383c88e netfilter: ipt_CLUSTERIP: check MAC address when duplicate config is set
[ Upstream commit 06aa151ad1fc74a49b45336672515774a678d78d ]

If same destination IP address config is already existing, that config is
just used. MAC address also should be same.
However, there is no MAC address checking routine.
So that MAC address checking routine is added.

test commands:
   %iptables -A INPUT -p tcp -i lo -d 192.168.0.5 --dport 80 \
	   -j CLUSTERIP --new --hashmode sourceip \
	   --clustermac 01:00:5e:00:00:20 --total-nodes 2 --local-node 1
   %iptables -A INPUT -p tcp -i lo -d 192.168.0.5 --dport 80 \
	   -j CLUSTERIP --new --hashmode sourceip \
	   --clustermac 01:00:5e:00:00:21 --total-nodes 2 --local-node 1

After this patch, above commands are disallowed.

Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-01-26 09:32:40 +01:00
Willem de Bruijn
eb02c17fcc ip: on queued skb use skb_header_pointer instead of pskb_may_pull
[ Upstream commit 4a06fa67c4da20148803525151845276cdb995c1 ]

Commit 2efd4fca70 ("ip: in cmsg IP(V6)_ORIGDSTADDR call
pskb_may_pull") avoided a read beyond the end of the skb linear
segment by calling pskb_may_pull.

That function can trigger a BUG_ON in pskb_expand_head if the skb is
shared, which it is when when peeking. It can also return ENOMEM.

Avoid both by switching to safer skb_header_pointer.

Fixes: 2efd4fca70 ("ip: in cmsg IP(V6)_ORIGDSTADDR call pskb_may_pull")
Reported-by: syzbot <syzkaller@googlegroups.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-22 21:40:31 +01:00
Yuchung Cheng
d7fe54c17a tcp: change txhash on SYN-data timeout
[ Upstream commit c5715b8fabfca0ef85903f8bad2189940ed41cc8 ]

Previously upon SYN timeouts the sender recomputes the txhash to
try a different path. However this does not apply on the initial
timeout of SYN-data (active Fast Open). Therefore an active IPv6
Fast Open connection may incur one second RTO penalty to take on
a new path after the second SYN retransmission uses a new flow label.

This patch removes this undesirable behavior so Fast Open changes
the flow label just like the regular connections. This also helps
avoid falsely disabling Fast Open on the sender which triggers
after two consecutive SYN timeouts on Fast Open.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Reviewed-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-22 21:40:30 +01:00
Eric Dumazet
e521703487 tcp: fix a race in inet_diag_dump_icsk()
[ Upstream commit f0c928d878e7d01b613c9ae5c971a6b1e473a938 ]

Alexei reported use after frees in inet_diag_dump_icsk() [1]

Because we use refcount_set() when various sockets are setup and
inserted into ehash, we also need to make sure inet_diag_dump_icsk()
wont race with the refcount_set() operations.

Jonathan Lemon sent a patch changing net_twsk_hashdance() but
other spots would need risky changes.

Instead, fix inet_diag_dump_icsk() as this bug came with
linux-4.10 only.

[1] Quoting Alexei :

First something iterating over sockets finds already freed tw socket:

refcount_t: increment on 0; use-after-free.
WARNING: CPU: 2 PID: 2738 at lib/refcount.c:153 refcount_inc+0x26/0x30
RIP: 0010:refcount_inc+0x26/0x30
RSP: 0018:ffffc90004c8fbc0 EFLAGS: 00010282
RAX: 000000000000002b RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff88085ee9d680 RSI: ffff88085ee954c8 RDI: ffff88085ee954c8
RBP: ffff88010ecbd2c0 R08: 0000000000000000 R09: 000000000000174c
R10: ffffffff81e7c5a0 R11: 0000000000000000 R12: 0000000000000000
R13: ffff8806ba9bf210 R14: ffffffff82304600 R15: ffff88010ecbd328
FS:  00007f81f5a7d700(0000) GS:ffff88085ee80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f81e2a95000 CR3: 000000069b2eb006 CR4: 00000000003606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 inet_diag_dump_icsk+0x2b3/0x4e0 [inet_diag]  // sock_hold(sk); in net/ipv4/inet_diag.c:1002
 ? kmalloc_large_node+0x37/0x70
 ? __kmalloc_node_track_caller+0x1cb/0x260
 ? __alloc_skb+0x72/0x1b0
 ? __kmalloc_reserve.isra.40+0x2e/0x80
 __inet_diag_dump+0x3b/0x80 [inet_diag]
 netlink_dump+0x116/0x2a0
 netlink_recvmsg+0x205/0x3c0
 sock_read_iter+0x89/0xd0
 __vfs_read+0xf7/0x140
 vfs_read+0x8a/0x140
 SyS_read+0x3f/0xa0
 do_syscall_64+0x5a/0x100

then a minute later twsk timer fires and hits two bad refcnts
for this freed socket:

refcount_t: decrement hit 0; leaking memory.
WARNING: CPU: 31 PID: 0 at lib/refcount.c:228 refcount_dec+0x2e/0x40
Modules linked in:
RIP: 0010:refcount_dec+0x2e/0x40
RSP: 0018:ffff88085f5c3ea8 EFLAGS: 00010296
RAX: 000000000000002c RBX: ffff88010ecbd2c0 RCX: 000000000000083f
RDX: 0000000000000000 RSI: 00000000000000f6 RDI: 000000000000003f
RBP: ffffc90003c77280 R08: 0000000000000000 R09: 00000000000017d3
R10: ffffffff81e7c5a0 R11: 0000000000000000 R12: ffffffff82ad2d80
R13: ffffffff8182de00 R14: ffff88085f5c3ef8 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88085f5c0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbe42685250 CR3: 0000000002209001 CR4: 00000000003606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 inet_twsk_kill+0x9d/0xc0  // inet_twsk_bind_unhash(tw, hashinfo);
 call_timer_fn+0x29/0x110
 run_timer_softirq+0x36b/0x3a0

refcount_t: underflow; use-after-free.
WARNING: CPU: 31 PID: 0 at lib/refcount.c:187 refcount_sub_and_test+0x46/0x50
RIP: 0010:refcount_sub_and_test+0x46/0x50
RSP: 0018:ffff88085f5c3eb8 EFLAGS: 00010296
RAX: 0000000000000026 RBX: ffff88010ecbd2c0 RCX: 000000000000083f
RDX: 0000000000000000 RSI: 00000000000000f6 RDI: 000000000000003f
RBP: ffff88010ecbd358 R08: 0000000000000000 R09: 000000000000185b
R10: ffffffff81e7c5a0 R11: 0000000000000000 R12: ffff88010ecbd358
R13: ffffffff8182de00 R14: ffff88085f5c3ef8 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88085f5c0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbe42685250 CR3: 0000000002209001 CR4: 00000000003606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 inet_twsk_put+0x12/0x20  // inet_twsk_put(tw);
 call_timer_fn+0x29/0x110
 run_timer_softirq+0x36b/0x3a0

Fixes: 67db3e4bfb ("tcp: no longer hold ehash lock while calling tcp_get_info()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Alexei Starovoitov <ast@kernel.org>
Cc: Jonathan Lemon <jonathan.lemon@gmail.com>
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-09 17:38:33 +01:00
Michal Kubecek
d5f9565c8d net: ipv4: do not handle duplicate fragments as overlapping
[ Upstream commit ade446403bfb79d3528d56071a84b15351a139ad ]

Since commit 7969e5c40d ("ip: discard IPv4 datagrams with overlapping
segments.") IPv4 reassembly code drops the whole queue whenever an
overlapping fragment is received. However, the test is written in a way
which detects duplicate fragments as overlapping so that in environments
with many duplicate packets, fragmented packets may be undeliverable.

Add an extra test and for (potentially) duplicate fragment, only drop the
new fragment rather than the whole queue. Only starting offset and length
are checked, not the contents of the fragments as that would be too
expensive. For similar reason, linear list ("run") of a rbtree node is not
iterated, we only check if the new fragment is a subset of the interval
covered by existing consecutive fragments.

v2: instead of an exact check iterating through linear list of an rbtree
node, only check if the new fragment is subset of the "run" (suggested
by Eric Dumazet)

Fixes: 7969e5c40d ("ip: discard IPv4 datagrams with overlapping segments.")
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>
2019-01-09 17:38:32 +01:00
Eric Dumazet
281731c817 net: clear skb->tstamp in forwarding paths
[ Upstream commit 8203e2d844d34af247a151d8ebd68553a6e91785 ]

Sergey reported that forwarding was no longer working
if fq packet scheduler was used.

This is caused by the recent switch to EDT model, since incoming
packets might have been timestamped by __net_timestamp()

__net_timestamp() uses ktime_get_real(), while fq expects packets
using CLOCK_MONOTONIC base.

The fix is to clear skb->tstamp in forwarding paths.

Fixes: 80b14dee2b ("net: Add a new socket option for a future transmit time.")
Fixes: fb420d5d91c1 ("tcp/fq: move back to CLOCK_MONOTONIC")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Sergey Matyukevich <geomatsi@gmail.com>
Tested-by: Sergey Matyukevich <geomatsi@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-09 17:38:31 +01:00
Willem de Bruijn
cde81154f8 ip: validate header length on virtual device xmit
[ Upstream commit cb9f1b783850b14cbd7f87d061d784a666dfba1f ]

KMSAN detected read beyond end of buffer in vti and sit devices when
passing truncated packets with PF_PACKET. The issue affects additional
ip tunnel devices.

Extend commit 76c0ddd8c3 ("ip6_tunnel: be careful when accessing the
inner header") and commit ccfec9e5cb ("ip_tunnel: be careful when
accessing the inner header").

Move the check to a separate helper and call at the start of each
ndo_start_xmit function in net/ipv4 and net/ipv6.

Minor changes:
- convert dev_kfree_skb to kfree_skb on error path,
  as dev_kfree_skb calls consume_skb which is not for error paths.
- use pskb_network_may_pull even though that is pedantic here,
  as the same as pskb_may_pull for devices without llheaders.
- do not cache ipv6 hdrs if used only once
  (unsafe across pskb_may_pull, was more relevant to earlier patch)

Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-09 17:38:31 +01:00
Gustavo A. R. Silva
360fb1db92 ipv4: Fix potential Spectre v1 vulnerability
[ Upstream commit 5648451e30a0d13d11796574919a359025d52cce ]

vr.vifi is indirectly controlled by user-space, hence leading to
a potential exploitation of the Spectre variant 1 vulnerability.

This issue was detected with the help of Smatch:

net/ipv4/ipmr.c:1616 ipmr_ioctl() warn: potential spectre issue 'mrt->vif_table' [r] (local cap)
net/ipv4/ipmr.c:1690 ipmr_compat_ioctl() warn: potential spectre issue 'mrt->vif_table' [r] (local cap)

Fix this by sanitizing vr.vifi before using it to index mrt->vif_table'

Notice that given that speculation windows are large, the policy is
to kill the speculation on the first load and not worry if it can be
completed with a dependent load/store [1].

[1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-01-09 17:38:31 +01:00