Commit graph

4953 commits

Author SHA1 Message Date
Artem Savkov 6b6ebb6b01 ip6_offload: check segs for NULL in ipv6_gso_segment.
segs needs to be checked for being NULL in ipv6_gso_segment() before calling
skb_shinfo(segs), otherwise kernel can run into a NULL-pointer dereference:

[   97.811262] BUG: unable to handle kernel NULL pointer dereference at 00000000000000cc
[   97.819112] IP: [<ffffffff816e52f9>] ipv6_gso_segment+0x119/0x2f0
[   97.825214] PGD 0 [   97.827047]
[   97.828540] Oops: 0000 [#1] SMP
[   97.831678] Modules linked in: vhost_net vhost macvtap macvlan nfsv3 rpcsec_gss_krb5
nfsv4 dns_resolver nfs fscache xt_CHECKSUM iptable_mangle ipt_MASQUERADE nf_nat_masquerade_ipv4
iptable_nat nf_nat_ipv4 nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 xt_conntrack nf_conntrack
ipt_REJECT nf_reject_ipv4 tun ebtable_filter ebtables ip6table_filter ip6_tables iptable_filter
bridge stp llc snd_hda_codec_realtek snd_hda_codec_hdmi snd_hda_codec_generic snd_hda_intel
snd_hda_codec edac_mce_amd snd_hda_core edac_core snd_hwdep kvm_amd snd_seq kvm snd_seq_device
snd_pcm irqbypass snd_timer ppdev parport_serial snd parport_pc k10temp pcspkr soundcore parport
sp5100_tco shpchp sg wmi i2c_piix4 acpi_cpufreq nfsd auth_rpcgss nfs_acl lockd grace sunrpc
ip_tables xfs libcrc32c sr_mod cdrom sd_mod ata_generic pata_acpi amdkfd amd_iommu_v2 radeon
broadcom bcm_phy_lib i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops
ttm ahci serio_raw tg3 firewire_ohci libahci pata_atiixp drm ptp libata firewire_core pps_core
i2c_core crc_itu_t fjes dm_mirror dm_region_hash dm_log dm_mod
[   97.927721] CPU: 1 PID: 3504 Comm: vhost-3495 Not tainted 4.9.0-7.el7.test.x86_64 #1
[   97.935457] Hardware name: AMD Snook/Snook, BIOS ESK0726A 07/26/2010
[   97.941806] task: ffff880129a1c080 task.stack: ffffc90001bcc000
[   97.947720] RIP: 0010:[<ffffffff816e52f9>]  [<ffffffff816e52f9>] ipv6_gso_segment+0x119/0x2f0
[   97.956251] RSP: 0018:ffff88012fc43a10  EFLAGS: 00010207
[   97.961557] RAX: 0000000000000000 RBX: ffff8801292c8700 RCX: 0000000000000594
[   97.968687] RDX: 0000000000000593 RSI: ffff880129a846c0 RDI: 0000000000240000
[   97.975814] RBP: ffff88012fc43a68 R08: ffff880129a8404e R09: 0000000000000000
[   97.982942] R10: 0000000000000000 R11: ffff880129a84076 R12: 00000020002949b3
[   97.990070] R13: ffff88012a580000 R14: 0000000000000000 R15: ffff88012a580000
[   97.997198] FS:  0000000000000000(0000) GS:ffff88012fc40000(0000) knlGS:0000000000000000
[   98.005280] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   98.011021] CR2: 00000000000000cc CR3: 0000000126c5d000 CR4: 00000000000006e0
[   98.018149] Stack:
[   98.020157]  00000000ffffffff ffff88012fc43ac8 ffffffffa017ad0a 000000000000000e
[   98.027584]  0000001300000000 0000000077d59998 ffff8801292c8700 00000020002949b3
[   98.035010]  ffff88012a580000 0000000000000000 ffff88012a580000 ffff88012fc43a98
[   98.042437] Call Trace:
[   98.044879]  <IRQ> [   98.046803]  [<ffffffffa017ad0a>] ? tg3_start_xmit+0x84a/0xd60 [tg3]
[   98.053156]  [<ffffffff815eeee0>] skb_mac_gso_segment+0xb0/0x130
[   98.059158]  [<ffffffff815eefd3>] __skb_gso_segment+0x73/0x110
[   98.064985]  [<ffffffff815ef40d>] validate_xmit_skb+0x12d/0x2b0
[   98.070899]  [<ffffffff815ef5d2>] validate_xmit_skb_list+0x42/0x70
[   98.077073]  [<ffffffff81618560>] sch_direct_xmit+0xd0/0x1b0
[   98.082726]  [<ffffffff815efd86>] __dev_queue_xmit+0x486/0x690
[   98.088554]  [<ffffffff8135c135>] ? cpumask_next_and+0x35/0x50
[   98.094380]  [<ffffffff815effa0>] dev_queue_xmit+0x10/0x20
[   98.099863]  [<ffffffffa09ce057>] br_dev_queue_push_xmit+0xa7/0x170 [bridge]
[   98.106907]  [<ffffffffa09ce161>] br_forward_finish+0x41/0xc0 [bridge]
[   98.113430]  [<ffffffff81627cf2>] ? nf_iterate+0x52/0x60
[   98.118735]  [<ffffffff81627d6b>] ? nf_hook_slow+0x6b/0xc0
[   98.124216]  [<ffffffffa09ce32c>] __br_forward+0x14c/0x1e0 [bridge]
[   98.130480]  [<ffffffffa09ce120>] ? br_dev_queue_push_xmit+0x170/0x170 [bridge]
[   98.137785]  [<ffffffffa09ce4bd>] br_forward+0x9d/0xb0 [bridge]
[   98.143701]  [<ffffffffa09cfbb7>] br_handle_frame_finish+0x267/0x560 [bridge]
[   98.150834]  [<ffffffffa09d0064>] br_handle_frame+0x174/0x2f0 [bridge]
[   98.157355]  [<ffffffff8102fb89>] ? sched_clock+0x9/0x10
[   98.162662]  [<ffffffff810b63b2>] ? sched_clock_cpu+0x72/0xa0
[   98.168403]  [<ffffffff815eccf5>] __netif_receive_skb_core+0x1e5/0xa20
[   98.174926]  [<ffffffff813659f9>] ? timerqueue_add+0x59/0xb0
[   98.180580]  [<ffffffff815ed548>] __netif_receive_skb+0x18/0x60
[   98.186494]  [<ffffffff815ee625>] process_backlog+0x95/0x140
[   98.192145]  [<ffffffff815edccd>] net_rx_action+0x16d/0x380
[   98.197713]  [<ffffffff8170cff1>] __do_softirq+0xd1/0x283
[   98.203106]  [<ffffffff8170b2bc>] do_softirq_own_stack+0x1c/0x30
[   98.209107]  <EOI> [   98.211029]  [<ffffffff8108a5c0>] do_softirq+0x50/0x60
[   98.216166]  [<ffffffff815ec853>] netif_rx_ni+0x33/0x80
[   98.221386]  [<ffffffffa09eeff7>] tun_get_user+0x487/0x7f0 [tun]
[   98.227388]  [<ffffffffa09ef3ab>] tun_sendmsg+0x4b/0x60 [tun]
[   98.233129]  [<ffffffffa0b68932>] handle_tx+0x282/0x540 [vhost_net]
[   98.239392]  [<ffffffffa0b68c25>] handle_tx_kick+0x15/0x20 [vhost_net]
[   98.245916]  [<ffffffffa0abacfe>] vhost_worker+0x9e/0xf0 [vhost]
[   98.251919]  [<ffffffffa0abac60>] ? vhost_umem_alloc+0x40/0x40 [vhost]
[   98.258440]  [<ffffffff81003a47>] ? do_syscall_64+0x67/0x180
[   98.264094]  [<ffffffff810a44d9>] kthread+0xd9/0xf0
[   98.268965]  [<ffffffff810a4400>] ? kthread_park+0x60/0x60
[   98.274444]  [<ffffffff8170a4d5>] ret_from_fork+0x25/0x30
[   98.279836] Code: 8b 93 d8 00 00 00 48 2b 93 d0 00 00 00 4c 89 e6 48 89 df 66 89 93 c2 00 00 00 ff 10 48 3d 00 f0 ff ff 49 89 c2 0f 87 52 01 00 00 <41> 8b 92 cc 00 00 00 48 8b 80 d0 00 00 00 44 0f b7 74 10 06 66
[   98.299425] RIP  [<ffffffff816e52f9>] ipv6_gso_segment+0x119/0x2f0
[   98.305612]  RSP <ffff88012fc43a10>
[   98.309094] CR2: 00000000000000cc
[   98.312406] ---[ end trace 726a2c7a2d2d78d0 ]---

Signed-off-by: Artem Savkov <asavkov@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-02 13:34:58 -05:00
Eli Cooper 80d1106aea Revert: "ip6_tunnel: Update skb->protocol to ETH_P_IPV6 in ip6_tnl_xmit()"
This reverts commit ae148b0858
("ip6_tunnel: Update skb->protocol to ETH_P_IPV6 in ip6_tnl_xmit()").

skb->protocol is now set in __ip_local_out() and __ip6_local_out() before
dst_output() is called. It is no longer necessary to do it for each tunnel.

Cc: stable@vger.kernel.org
Signed-off-by: Eli Cooper <elicooper@gmx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-02 12:34:22 -05:00
Eli Cooper b4e479a96f ipv6: Set skb->protocol properly for local output
When xfrm is applied to TSO/GSO packets, it follows this path:

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

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

This patch sets skb->protocol to ETH_P_IPV6 before dst_output() is called,
fixing a bug where GSO packets sent through an ipip6 tunnel are dropped
when xfrm is involved.

Cc: stable@vger.kernel.org
Signed-off-by: Eli Cooper <elicooper@gmx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-02 12:34:22 -05:00
David S. Miller 7bbf91ce27 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec
Steffen Klassert says:

====================
pull request (net): ipsec 2016-12-01

1) Change the error value when someone tries to run 32bit
   userspace on a 64bit host from -ENOTSUPP to the userspace
   exported -EOPNOTSUPP. Fix from Yi Zhao.

2) On inbound, ESN sequence numbers are already in network
   byte order. So don't try to convert it again, this fixes
   integrity verification for ESN. Fixes from Tobias Brunner.

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

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-01 11:35:49 -05:00
David S. Miller 3d2dd617fb Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

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

This is a large batch of Netfilter fixes for net, they are:

1) Three patches to fix NAT conversion to rhashtable: Switch to rhlist
   structure that allows to have several objects with the same key.
   Moreover, fix wrong comparison logic in nf_nat_bysource_cmp() as this is
   expecting a return value similar to memcmp(). Change location of
   the nat_bysource field in the nf_conn structure to avoid zeroing
   this as it breaks interaction with SLAB_DESTROY_BY_RCU and lead us
   to crashes. From Florian Westphal.

2) Don't allow malformed fragments go through in IPv6, drop them,
   otherwise we hit GPF, patch from Florian Westphal.

3) Fix crash if attributes are missing in nft_range, from Liping Zhang.

4) Fix arptables 32-bits userspace 64-bits kernel compat, from Hongxu Jia.

5) Two patches from David Ahern to fix netfilter interaction with vrf.
   From David Ahern.

6) Fix element timeout calculation in nf_tables, we take milliseconds
   from userspace, but we use jiffies from kernelspace. Patch from
   Anders K.  Pedersen.

7) Missing validation length netlink attribute for nft_hash, from
   Laura Garcia.

8) Fix nf_conntrack_helper documentation, we don't default to off
   anymore for a bit of time so let's get this in sync with the code.

I know is late but I think these are important, specifically the NAT
bits, as they are mostly addressing fallout from recent changes. I also
read there are chances to have -rc8, if that is the case, that would
also give us a bit more time to test this.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-01 11:04:41 -05:00
Guillaume Nault 0382a25af3 l2tp: lock socket before checking flags in connect()
Socket flags aren't updated atomically, so the socket must be locked
while reading the SOCK_ZAPPED flag.

This issue exists for both l2tp_ip and l2tp_ip6. For IPv6, this patch
also brings error handling for __ip6_datagram_connect() failures.

Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-30 14:14:07 -05:00
Tobias Brunner a55e23864d esp6: Fix integrity verification when ESN are used
When handling inbound packets, the two halves of the sequence number
stored on the skb are already in network order.

Fixes: 000ae7b269 ("esp6: Switch to new AEAD interface")
Signed-off-by: Tobias Brunner <tobias@strongswan.org>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2016-11-30 11:10:16 +01:00
Florian Westphal 9b57da0630 netfilter: ipv6: nf_defrag: drop mangled skb on ream error
Dmitry Vyukov reported GPF in network stack that Andrey traced down to
negative nh offset in nf_ct_frag6_queue().

Problem is that all network headers before fragment header are pulled.
Normal ipv6 reassembly will drop the skb when errors occur further down
the line.

netfilter doesn't do this, and instead passed the original fragment
along.  That was also fine back when netfilter ipv6 defrag worked with
cloned fragments, as the original, pristine fragment was passed on.

So we either have to undo the pull op, or discard such fragments.
Since they're malformed after all (e.g. overlapping fragment) it seems
preferrable to just drop them.

Same for temporary errors -- it doesn't make sense to accept (and
perhaps forward!) only some fragments of same datagram.

Fixes: 029f7f3b87 ("netfilter: ipv6: nf_defrag: avoid/free clone operations")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Debugged-by: Andrey Konovalov <andreyknvl@google.com>
Diagnosed-by: Eric Dumazet <Eric Dumazet <edumazet@google.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-11-29 20:23:58 +01:00
David Ahern 79dc7e3f1c net: handle no dst on skb in icmp6_send
Andrey reported the following while fuzzing the kernel with syzkaller:

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
Modules linked in:
CPU: 0 PID: 3859 Comm: a.out Not tainted 4.9.0-rc6+ #429
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
task: ffff8800666d4200 task.stack: ffff880067348000
RIP: 0010:[<ffffffff833617ec>]  [<ffffffff833617ec>]
icmp6_send+0x5fc/0x1e30 net/ipv6/icmp.c:451
RSP: 0018:ffff88006734f2c0  EFLAGS: 00010206
RAX: ffff8800666d4200 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: dffffc0000000000 RDI: 0000000000000018
RBP: ffff88006734f630 R08: ffff880064138418 R09: 0000000000000003
R10: dffffc0000000000 R11: 0000000000000005 R12: 0000000000000000
R13: ffffffff84e7e200 R14: ffff880064138484 R15: ffff8800641383c0
FS:  00007fb3887a07c0(0000) GS:ffff88006cc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000000 CR3: 000000006b040000 CR4: 00000000000006f0
Stack:
 ffff8800666d4200 ffff8800666d49f8 ffff8800666d4200 ffffffff84c02460
 ffff8800666d4a1a 1ffff1000ccdaa2f ffff88006734f498 0000000000000046
 ffff88006734f440 ffffffff832f4269 ffff880064ba7456 0000000000000000
Call Trace:
 [<ffffffff83364ddc>] icmpv6_param_prob+0x2c/0x40 net/ipv6/icmp.c:557
 [<     inline     >] ip6_tlvopt_unknown net/ipv6/exthdrs.c:88
 [<ffffffff83394405>] ip6_parse_tlv+0x555/0x670 net/ipv6/exthdrs.c:157
 [<ffffffff8339a759>] ipv6_parse_hopopts+0x199/0x460 net/ipv6/exthdrs.c:663
 [<ffffffff832ee773>] ipv6_rcv+0xfa3/0x1dc0 net/ipv6/ip6_input.c:191
 ...

icmp6_send / icmpv6_send is invoked for both rx and tx paths. In both
cases the dst->dev should be preferred for determining the L3 domain
if the dst has been set on the skb. Fallback to the skb->dev if it has
not. This covers the case reported here where icmp6_send is invoked on
Rx before the route lookup.

Fixes: 5d41ce29e ("net: icmp6_send should use dst dev to determine L3 domain")
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-28 16:13:01 -05:00
David S. Miller 8eb4adf60b Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec
Steffen Klassert says:

====================
pull request (net): ipsec 2016-11-25

1) Fix a refcount leak in vti6.
   From Nicolas Dichtel.

2) Fix a wrong if statement in xfrm_sk_policy_lookup.
   From Florian Westphal.

3) The flowcache watermarks are per cpu. Take this into
   account when comparing to the threshold where we
   refusing new allocations. From Miroslav Urbanek.

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

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-27 20:21:48 -05:00
Eric Dumazet 30c7be26fd udplite: call proper backlog handlers
In commits 93821778de ("udp: Fix rcv socket locking") and
f7ad74fef3 ("net/ipv6/udp: UDP encapsulation: break backlog_rcv into
__udpv6_queue_rcv_skb") UDP backlog handlers were renamed, but UDPlite
was forgotten.

This leads to crashes if UDPlite header is pulled twice, which happens
starting from commit e6afc8ace6 ("udp: remove headers from UDP packets
before queueing")

Bug found by syzkaller team, thanks a lot guys !

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

Fixes: 93821778de ("udp: Fix rcv socket locking")
Fixes: f7ad74fef3 ("net/ipv6/udp: UDP encapsulation: break backlog_rcv into __udpv6_queue_rcv_skb")
Fixes: e6afc8ace6 ("udp: remove headers from UDP packets before queueing")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-24 15:32:14 -05:00
Paolo Abeni 764d3be6e4 ipv6: bump genid when the IFA_F_TENTATIVE flag is clear
When an ipv6 address has the tentative flag set, it can't be
used as source for egress traffic, while the associated route,
if any, can be looked up and even stored into some dst_cache.

In the latter scenario, the source ipv6 address selected and
stored in the cache is most probably wrong (e.g. with
link-local scope) and the entity using the dst_cache will
experience lack of ipv6 connectivity until said cache is
cleared or invalidated.

Overall this may cause lack of connectivity over most IPv6 tunnels
(comprising geneve and vxlan), if the first egress packet reaches
the tunnel before the DaD is completed for the used ipv6
address.

This patch bumps a new genid after that the IFA_F_TENTATIVE flag
is cleared, so that dst_cache will be invalidated on
next lookup and ipv6 connectivity restored.

Fixes: 0c1d70af92 ("net: use dst_cache for vxlan device")
Fixes: 468dfffcd7 ("geneve: add dst caching support")
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-24 12:04:10 -05:00
David Ahern 00b4422fe3 netfilter: Update nf_send_reset6 to consider L3 domain
nf_send_reset6 is not considering the L3 domain and lookups are sent
to the wrong table. For example consider the following output rule:

ip6tables -A OUTPUT -p tcp --dport 12345 -j REJECT --reject-with tcp-reset

using perf to analyze lookups via the fib6_table_lookup tracepoint shows:

swapper     0 [001]   248.787816: fib6:fib6_table_lookup: table 255 oif 0 iif 1 src 2100:1::3 dst 2100:1:
        ffffffff81439cdc perf_trace_fib6_table_lookup ([kernel.kallsyms])
        ffffffff814c1ce3 trace_fib6_table_lookup ([kernel.kallsyms])
        ffffffff814c3e89 ip6_pol_route ([kernel.kallsyms])
        ffffffff814c40d5 ip6_pol_route_output ([kernel.kallsyms])
        ffffffff814e7b6f fib6_rule_action ([kernel.kallsyms])
        ffffffff81437f60 fib_rules_lookup ([kernel.kallsyms])
        ffffffff814e7c79 fib6_rule_lookup ([kernel.kallsyms])
        ffffffff814c2541 ip6_route_output_flags ([kernel.kallsyms])
                     528 nf_send_reset6 ([nf_reject_ipv6])

The lookup is directed to table 255 rather than the table associated with
the device via the L3 domain. Update nf_send_reset6 to pull the L3 domain
from the dst currently attached to the skb.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-11-24 12:47:08 +01:00
Paolo Abeni b5c2d49544 ip6_tunnel: disable caching when the traffic class is inherited
If an ip6 tunnel is configured to inherit the traffic class from
the inner header, the dst_cache must be disabled or it will foul
the policy routing.

The issue is apprently there since at leat Linux-2.6.12-rc2.

Reported-by: Liam McBirnie <liam.mcbirnie@boeing.com>
Cc: Liam McBirnie <liam.mcbirnie@boeing.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-17 12:08:56 -05:00
Pablo Neira 73e2d5e34b udp: restore UDPlite many-cast delivery
Honor udptable parameter that is passed to __udp*_lib_mcast_deliver(),
otherwise udplite broadcast/multicast use the wrong table and it breaks.

Fixes: 2dc41cff75 ("udp: Use hash2 for long hash1 chains in __udp*_lib_mcast_deliver.")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-15 22:14:27 -05:00
Eric Dumazet ac6e780070 tcp: take care of truncations done by sk_filter()
With syzkaller help, Marco Grassi found a bug in TCP stack,
crashing in tcp_collapse()

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

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

Many thanks to syzkaller team and Marco for giving us a reproducer.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Marco Grassi <marco.gra@gmail.com>
Reported-by: Vladis Dronov <vdronov@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-13 12:30:02 -05:00
David Ahern 9b6c14d51b net: tcp response should set oif only if it is L3 master
Lorenzo noted an Android unit test failed due to e0d56fdd73:
"The expectation in the test was that the RST replying to a SYN sent to a
closed port should be generated with oif=0. In other words it should not
prefer the interface where the SYN came in on, but instead should follow
whatever the routing table says it should do."

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

Fixes: e0d56fdd73 ("net: l3mdev: remove redundant calls")
Reported-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Tested-by: Lorenzo Colitti <lorenzo@google.com>
Acked-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-09 22:32:10 -05:00
David S. Miller 9fa684ec86 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

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

The following patchset contains a larger than usual batch of Netfilter
fixes for your net tree. This series contains a mixture of old bugs and
recently introduced bugs, they are:

1) Fix a crash when using nft_dynset with nft_set_rbtree, which doesn't
   support the set element updates from the packet path. From Liping
   Zhang.

2) Fix leak when nft_expr_clone() fails, from Liping Zhang.

3) Fix a race when inserting new elements to the set hash from the
   packet path, also from Liping.

4) Handle segmented TCP SIP packets properly, basically avoid that the
   INVITE in the allow header create bogus expectations by performing
   stricter SIP message parsing, from Ulrich Weber.

5) nft_parse_u32_check() should return signed integer for errors, from
   John Linville.

6) Fix wrong allocation instead of connlabels, allocate 16 instead of
   32 bytes, from Florian Westphal.

7) Fix compilation breakage when building the ip_vs_sync code with
   CONFIG_OPTIMIZE_INLINING on x86, from Arnd Bergmann.

8) Destroy the new set if the transaction object cannot be allocated,
   also from Liping Zhang.

9) Use device to route duplicated packets via nft_dup only when set by
   the user, otherwise packets may not follow the right route, again
   from Liping.

10) Fix wrong maximum genetlink attribute definition in IPVS, from
    WANG Cong.

11) Ignore untracked conntrack objects from xt_connmark, from Florian
    Westphal.

12) Allow to use conntrack helpers that are registered NFPROTO_UNSPEC
    via CT target, otherwise we cannot use the h.245 helper, from
    Florian.

13) Revisit garbage collection heuristic in the new workqueue-based
    timer approach for conntrack to evict objects earlier, again from
    Florian.

14) Fix crash in nf_tables when inserting an element into a verdict map,
    from Liping Zhang.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-09 20:38:18 -05:00
Maciej Żenczykowski fb56be83e4 net-ipv6: on device mtu change do not add mtu to mtu-less routes
Routes can specify an mtu explicitly or inherit the mtu from
the underlying device - this inheritance is implemented in
dst->ops->mtu handlers ip6_mtu() and ip6_blackhole_mtu().

Currently changing the mtu of a device adds mtu explicitly
to routes using that device.

ie.
  # ip link set dev lo mtu 65536
  # ip -6 route add local 2000::1 dev lo
  # ip -6 route get 2000::1
  local 2000::1 dev lo  table local  src ...  metric 1024  pref medium

  # ip link set dev lo mtu 65535
  # ip -6 route get 2000::1
  local 2000::1 dev lo  table local  src ...  metric 1024  mtu 65535 pref medium

  # ip link set dev lo mtu 65536
  # ip -6 route get 2000::1
  local 2000::1 dev lo  table local  src ...  metric 1024  mtu 65536 pref medium

  # ip -6 route del local 2000::1

After this patch the route entry no longer changes unless it already has an mtu.
There is no need: this inheritance is already done in ip6_mtu()

  # ip link set dev lo mtu 65536
  # ip -6 route add local 2000::1 dev lo
  # ip -6 route add local 2000::2 dev lo mtu 2000
  # ip -6 route get 2000::1; ip -6 route get 2000::2
  local 2000::1 dev lo  table local  src ...  metric 1024  pref medium
  local 2000::2 dev lo  table local  src ...  metric 1024  mtu 2000 pref medium

  # ip link set dev lo mtu 65535
  # ip -6 route get 2000::1; ip -6 route get 2000::2
  local 2000::1 dev lo  table local  src ...  metric 1024  pref medium
  local 2000::2 dev lo  table local  src ...  metric 1024  mtu 2000 pref medium

  # ip link set dev lo mtu 1501
  # ip -6 route get 2000::1; ip -6 route get 2000::2
  local 2000::1 dev lo  table local  src ...  metric 1024  pref medium
  local 2000::2 dev lo  table local  src ...  metric 1024  mtu 1501 pref medium

  # ip link set dev lo mtu 65536
  # ip -6 route get 2000::1; ip -6 route get 2000::2
  local 2000::1 dev lo  table local  src ...  metric 1024  pref medium
  local 2000::2 dev lo  table local  src ...  metric 1024  mtu 65536 pref medium

  # ip -6 route del local 2000::1
  # ip -6 route del local 2000::2

This is desirable because changing device mtu and then resetting it
to the previous value shouldn't change the user visible routing table.

Signed-off-by: Maciej Żenczykowski <maze@google.com>
CC: Eric Dumazet <edumazet@google.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-09 13:19:32 -05:00
David Ahern 5d41ce29e3 net: icmp6_send should use dst dev to determine L3 domain
icmp6_send is called in response to some event. The skb may not have
the device set (skb->dev is NULL), but it is expected to have a dst set.
Update icmp6_send to use the dst on the skb to determine L3 domain.

Fixes: ca254490c8 ("net: Add VRF support to IPv6 stack")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-07 20:30:19 -05:00
Eli Cooper 4fd19c15de ip6_udp_tunnel: remove unused IPCB related codes
Some IPCB fields are currently set in udp_tunnel6_xmit_skb(), which are
never used before it reaches ip6tunnel_xmit(), and past that point the
control buffer is no longer interpreted as IPCB.

This clears these unused IPCB related codes. Currently there is no skb
scrubbing in ip6_udp_tunnel, otherwise IPCB(skb)->opt might need to be
cleared for IPv4 packets, as shown in 5146d1f151
("tunnel: Clear IPCB(skb)->opt before dst_link_failure called").

Signed-off-by: Eli Cooper <elicooper@gmx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-02 15:18:36 -04:00
Xin Long 19bda36c42 ipv6: add mtu lock check in __ip6_rt_update_pmtu
Prior to this patch, ipv6 didn't do mtu lock check in ip6_update_pmtu.
It leaded to that mtu lock doesn't really work when receiving the pkt
of ICMPV6_PKT_TOOBIG.

This patch is to add mtu lock check in __ip6_rt_update_pmtu just as ipv4
did in __ip_rt_update_pmtu.

Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-31 14:24:24 -04:00
Jakub Sitnicki f89c56ce71 ipv6: Don't use ufo handling on later transformed packets
Similar to commit c146066ab8 ("ipv4: Don't use ufo handling on later
transformed packets"), don't perform UFO on packets that will be IPsec
transformed. To detect it we rely on the fact that headerlen in
dst_entry is non-zero only for transformation bundles (xfrm_dst
objects).

Unwanted segmentation can be observed with a NETIF_F_UFO capable device,
such as a dummy device:

  DEV=dum0 LEN=1493

  ip li add $DEV type dummy
  ip addr add fc00::1/64 dev $DEV nodad
  ip link set $DEV up
  ip xfrm policy add dir out src fc00::1 dst fc00::2 \
     tmpl src fc00::1 dst fc00::2 proto esp spi 1
  ip xfrm state add src fc00::1 dst fc00::2 \
     proto esp spi 1 enc 'aes' 0x0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b0b

  tcpdump -n -nn -i $DEV -t &
  socat /dev/zero,readbytes=$LEN udp6:[fc00::2]:$LEN

tcpdump output before:

  IP6 fc00::1 > fc00::2: frag (0|1448) ESP(spi=0x00000001,seq=0x1), length 1448
  IP6 fc00::1 > fc00::2: frag (1448|48)
  IP6 fc00::1 > fc00::2: ESP(spi=0x00000001,seq=0x2), length 88

... and after:

  IP6 fc00::1 > fc00::2: frag (0|1448) ESP(spi=0x00000001,seq=0x1), length 1448
  IP6 fc00::1 > fc00::2: frag (1448|80)

Fixes: e89e9cf539 ("[IPv4/IPv6]: UFO Scatter-gather approach")

Signed-off-by: Jakub Sitnicki <jkbs@redhat.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-31 13:10:41 -04:00
Liping Zhang b73b8a1ba5 netfilter: nft_dup: do not use sreg_dev if the user doesn't specify it
The NFTA_DUP_SREG_DEV attribute is not a must option, so we should use it
in routing lookup only when the user specify it.

Fixes: d877f07112 ("netfilter: nf_tables: add nft_dup expression")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-10-31 13:17:38 +01:00
Eli Cooper ae148b0858 ip6_tunnel: Update skb->protocol to ETH_P_IPV6 in ip6_tnl_xmit()
This patch updates skb->protocol to ETH_P_IPV6 in ip6_tnl_xmit() when an
IPv6 header is installed to a socket buffer.

This is not a cosmetic change.  Without updating this value, GSO packets
transmitted through an ipip6 tunnel have the protocol of ETH_P_IP and
skb_mac_gso_segment() will attempt to call gso_segment() for IPv4,
which results in the packets being dropped.

Fixes: b8921ca83e ("ip4ip6: Support for GSO/GRO")
Signed-off-by: Eli Cooper <elicooper@gmx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-29 14:49:31 -04:00
Craig Gallek e4cabca549 inet: Fix missing return value in inet6_hash
As part of a series to implement faster SO_REUSEPORT lookups,
commit 086c653f58 ("sock: struct proto hash function may error")
added return values to protocol hash functions and
commit 496611d7b5 ("inet: create IPv6-equivalent inet_hash function")
implemented a new hash function for IPv6.  However, the latter does
not respect the former's convention.

This properly propagates the hash errors in the IPv6 case.

Fixes: 496611d7b5 ("inet: create IPv6-equivalent inet_hash function")
Reported-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Craig Gallek <kraig@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-29 12:01:49 -04:00
David Ahern d5d32e4b76 net: ipv6: Do not consider link state for nexthop validation
Similar to IPv4, do not consider link state when validating next hops.

Currently, if the link is down default routes can fail to insert:
 $ ip -6 ro add vrf blue default via 2100:2::64 dev eth2
 RTNETLINK answers: No route to host

With this patch the command succeeds.

Fixes: 8c14586fc3 ("net: ipv6: Use passed in table for nexthop lookups")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27 16:33:12 -04:00
David Ahern 830218c1ad net: ipv6: Fix processing of RAs in presence of VRF
rt6_add_route_info and rt6_add_dflt_router were updated to pull the FIB
table from the device index, but the corresponding rt6_get_route_info
and rt6_get_dflt_router functions were not leading to the failure to
process RA's:

    ICMPv6: RA: ndisc_router_discovery failed to add default route

Fix the 'get' functions by using the table id associated with the
device when applicable.

Also, now that default routes can be added to tables other than the
default table, rt6_purge_dflt_routers needs to be updated as well to
look at all tables. To handle that efficiently, add a flag to the table
denoting if it is has a default route via RA.

Fixes: ca254490c8 ("net: Add VRF support to IPv6 stack")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27 16:30:52 -04:00
Eric Dumazet 10df8e6152 udp: fix IP_CHECKSUM handling
First bug was added in commit ad6f939ab1 ("ip: Add offset parameter to
ip_cmsg_recv") : Tom missed that ipv4 udp messages could be received on
AF_INET6 socket. ip_cmsg_recv(msg, skb) should have been replaced by
ip_cmsg_recv_offset(msg, skb, sizeof(struct udphdr));

Then commit e6afc8ace6 ("udp: remove headers from UDP packets before
queueing") forgot to adjust the offsets now UDP headers are pulled
before skb are put in receive queue.

Fixes: ad6f939ab1 ("ip: Add offset parameter to ip_cmsg_recv")
Fixes: e6afc8ace6 ("udp: remove headers from UDP packets before queueing")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Sam Kumar <samanthakumar@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Tested-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-26 17:33:22 -04:00
Jason A. Donenfeld b678aa578c ipv6: do not increment mac header when it's unset
Otherwise we'll overflow the integer. This occurs when layer 3 tunneled
packets are handed off to the IPv6 layer.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-23 17:38:58 -04:00
WANG Cong 8651be8f14 ipv6: fix a potential deadlock in do_ipv6_setsockopt()
Baozeng reported this deadlock case:

       CPU0                    CPU1
       ----                    ----
  lock([  165.136033] sk_lock-AF_INET6);
                               lock([  165.136033] rtnl_mutex);
                               lock([  165.136033] sk_lock-AF_INET6);
  lock([  165.136033] rtnl_mutex);

Similar to commit 87e9f03159
("ipv4: fix a potential deadlock in mcast getsockopt() path")
this is due to we still have a case, ipv6_sock_mc_close(),
where we acquire sk_lock before rtnl_lock. Close this deadlock
with the similar solution, that is always acquire rtnl lock first.

Fixes: baf606d9c9 ("ipv4,ipv6: grab rtnl before locking the socket")
Reported-by: Baozeng Ding <sploving1@gmail.com>
Tested-by: Baozeng Ding <sploving1@gmail.com>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-21 11:29:02 -04:00
Eric Dumazet 286c72deab udp: must lock the socket in udp_disconnect()
Baozeng Ding reported KASAN traces showing uses after free in
udp_lib_get_port() and other related UDP functions.

A CONFIG_DEBUG_PAGEALLOC=y kernel would eventually crash.

I could write a reproducer with two threads doing :

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

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

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

Problem is that udp_disconnect() could run without holding socket lock,
and this was causing list corruptions.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Baozeng Ding <sploving1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-20 14:45:52 -04:00
Sabrina Dubroca fcd91dd449 net: add recursion limit to GRO
Currently, GRO can do unlimited recursion through the gro_receive
handlers.  This was fixed for tunneling protocols by limiting tunnel GRO
to one level with encap_mark, but both VLAN and TEB still have this
problem.  Thus, the kernel is vulnerable to a stack overflow, if we
receive a packet composed entirely of VLAN headers.

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

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

Fixes: CVE-2016-7039
Fixes: 9b174d88c2 ("net: Add Transparent Ethernet Bridging GRO support.")
Fixes: 66e5133f19 ("vlan: Add GRO support for non hardware accelerated vlan")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-20 14:32:22 -04:00
Jiri Bohac 7aa8e63f0d ipv6: properly prevent temp_prefered_lft sysctl race
The check for an underflow of tmp_prefered_lft is always false
because tmp_prefered_lft is unsigned. The intention of the check
was to guard against racing with an update of the
temp_prefered_lft sysctl, potentially resulting in an underflow.

As suggested by David Miller, the best way to prevent the race is
by reading the sysctl variable using READ_ONCE.

Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Fixes: 76506a986d ("IPv6: fix DESYNC_FACTOR")
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-20 14:29:11 -04:00
David Ahern a04a480d43 net: Require exact match for TCP socket lookups if dif is l3mdev
Currently, socket lookups for l3mdev (vrf) use cases can match a socket
that is bound to a port but not a device (ie., a global socket). If the
sysctl tcp_l3mdev_accept is not set this leads to ack packets going out
based on the main table even though the packet came in from an L3 domain.
The end result is that the connection does not establish creating
confusion for users since the service is running and a socket shows in
ss output. Fix by requiring an exact dif to sk_bound_dev_if match if the
skb came through an interface enslaved to an l3mdev device and the
tcp_l3mdev_accept is not set.

skb's through an l3mdev interface are marked by setting a flag in
inet{6}_skb_parm. The IPv6 variant is already set; this patch adds the
flag for IPv4. Using an skb flag avoids a device lookup on the dif. The
flag is set in the VRF driver using the IP{6}CB macros. For IPv4, the
inet_skb_parm struct is moved in the cb per commit 971f10eca1, so the
match function in the TCP stack needs to use TCP_SKB_CB. For IPv6, the
move is done after the socket lookup, so IP6CB is used.

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

Fixes: 193125dbd8 ("net: Introduce VRF device driver")
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-17 10:17:05 -04:00
Jiri Bohac 76506a986d IPv6: fix DESYNC_FACTOR
The IPv6 temporary address generation uses a variable called DESYNC_FACTOR
to prevent hosts updating the addresses at the same time. Quoting RFC 4941:

   ... The value DESYNC_FACTOR is a random value (different for each
   client) that ensures that clients don't synchronize with each other and
   generate new addresses at exactly the same time ...

DESYNC_FACTOR is defined as:

   DESYNC_FACTOR -- A random value within the range 0 - MAX_DESYNC_FACTOR.
   It is computed once at system start (rather than each time it is used)
   and must never be greater than (TEMP_VALID_LIFETIME - REGEN_ADVANCE).

First, I believe the RFC has a typo in it and meant to say: "and must
never be greater than (TEMP_PREFERRED_LIFETIME - REGEN_ADVANCE)"

The reason is that at various places in the RFC, DESYNC_FACTOR is used in
a calculation like (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR) or
(TEMP_PREFERRED_LIFETIME - REGEN_ADVANCE - DESYNC_FACTOR). It needs to be
smaller than (TEMP_PREFERRED_LIFETIME - REGEN_ADVANCE) for the result of
these calculations to be larger than zero. It's never used in a
calculation together with TEMP_VALID_LIFETIME.

I already submitted an errata to the rfc-editor:
https://www.rfc-editor.org/errata_search.php?rfc=4941

The Linux implementation of DESYNC_FACTOR is very wrong:
max_desync_factor is used in places DESYNC_FACTOR should be used.
max_desync_factor is initialized to the RFC-recommended value for
MAX_DESYNC_FACTOR (600) but the whole point is to get a _random_ value.

And nothing ensures that the value used is not greater than
(TEMP_PREFERRED_LIFETIME - REGEN_ADVANCE), which leads to underflows.  The
effect can easily be observed when setting the temp_prefered_lft sysctl
e.g. to 60. The preferred lifetime of the temporary addresses will be
bogus.

TEMP_PREFERRED_LIFETIME and REGEN_ADVANCE are not constants and can be
influenced by these three sysctls: regen_max_retry, dad_transmits and
temp_prefered_lft. Thus, the upper bound for desync_factor needs to be
re-calculated each time a new address is generated and if desync_factor is
larger than the new upper bound, a new random value needs to be
re-generated.

And since we already have max_desync_factor configurable per interface, we
also need to calculate and store desync_factor per interface.

Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-14 10:59:15 -04:00
Jiri Bohac 9d6280da39 IPv6: Drop the temporary address regen_timer
The randomized interface identifier (rndid) was periodically updated from
the regen_timer timer. Simplify the code by updating the rndid only when
needed by ipv6_try_regen_rndid().

This makes the follow-up DESYNC_FACTOR fix much simpler.  Also it fixes a
reference counting error in this error path, where an in6_dev_put was
missing:
		err = addrconf_sysctl_register(ndev);
		if (err) {
			ipv6_mc_destroy_dev(ndev);
	-               del_timer(&ndev->regen_timer);
			snmp6_unregister_dev(ndev);
			goto err_release;

Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-14 10:59:15 -04:00
Nicolas Dichtel a220445f9f ipv6: correctly add local routes when lo goes up
The goal of the patch is to fix this scenario:
 ip link add dummy1 type dummy
 ip link set dummy1 up
 ip link set lo down ; ip link set lo up

After that sequence, the local route to the link layer address of dummy1 is
not there anymore.

When the loopback is set down, all local routes are deleted by
addrconf_ifdown()/rt6_ifdown(). At this time, the rt6_info entry still
exists, because the corresponding idev has a reference on it. After the rcu
grace period, dst_rcu_free() is called, and thus ___dst_free(), which will
set obsolete to DST_OBSOLETE_DEAD.

In this case, init_loopback() is called before dst_rcu_free(), thus
obsolete is still sets to something <= 0. So, the function doesn't add the
route again. To avoid that race, let's check the rt6 refcnt instead.

Fixes: 25fb6ca4ed ("net IPv6 : Fix broken IPv6 routing table after loopback down-up")
Fixes: a881ae1f62 ("ipv6: don't call addrconf_dst_alloc again when enable lo")
Fixes: 33d99113b1 ("ipv6: reallocate addrconf router for ipv6 address when lo device up")
Reported-by: Francesco Santoro <francesco.santoro@6wind.com>
Reported-by: Samuel Gauthier <samuel.gauthier@6wind.com>
CC: Balakumaran Kannan <Balakumaran.Kannan@ap.sony.com>
CC: Maruthi Thotad <Maruthi.Thotad@ap.sony.com>
CC: Sabrina Dubroca <sd@queasysnail.net>
CC: Hannes Frederic Sowa <hannes@stressinduktion.org>
CC: Weilong Chen <chenweilong@huawei.com>
CC: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-14 10:05:14 -04:00
Vadim Fedorenko 68d00f332e ip6_tunnel: fix ip6_tnl_lookup
The commit ea3dc9601b ("ip6_tunnel: Add support for wildcard tunnel
endpoints.") introduces support for wildcards in tunnels endpoints,
but in some rare circumstances ip6_tnl_lookup selects wrong tunnel
interface relying only on source or destination address of the packet
and not checking presence of wildcard in tunnels endpoints. Later in
ip6_tnl_rcv this packets can be dicarded because of difference in
ipproto even if fallback device have proper ipproto configuration.

This patch adds checks of wildcard endpoint in tunnel avoiding such
behavior

Fixes: ea3dc9601b ("ip6_tunnel: Add support for wildcard tunnel endpoints.")
Signed-off-by: Vadim Fedorenko <junk@yandex-team.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-14 10:01:26 -04:00
Eric Dumazet 8ce48623f0 ipv6: tcp: restore IP6CB for pktoptions skbs
Baozeng Ding reported following KASAN splat :

BUG: KASAN: use-after-free in ip6_datagram_recv_specific_ctl+0x13f1/0x15c0 at addr ffff880029c84ec8
Read of size 1 by task poc/25548
Call Trace:
 [<ffffffff82cf43c9>] dump_stack+0x12e/0x185 /lib/dump_stack.c:15
 [<     inline     >] print_address_description /mm/kasan/report.c:204
 [<ffffffff817ced3b>] kasan_report_error+0x48b/0x4b0 /mm/kasan/report.c:283
 [<     inline     >] kasan_report /mm/kasan/report.c:303
 [<ffffffff817ced9e>] __asan_report_load1_noabort+0x3e/0x40 /mm/kasan/report.c:321
 [<ffffffff85c71da1>] ip6_datagram_recv_specific_ctl+0x13f1/0x15c0 /net/ipv6/datagram.c:687
 [<ffffffff85c734c3>] ip6_datagram_recv_ctl+0x33/0x40
 [<ffffffff85c0b07c>] do_ipv6_getsockopt.isra.4+0xaec/0x2150
 [<ffffffff85c0c7f6>] ipv6_getsockopt+0x116/0x230
 [<ffffffff859b5a12>] tcp_getsockopt+0x82/0xd0 /net/ipv4/tcp.c:3035
 [<ffffffff855fb385>] sock_common_getsockopt+0x95/0xd0 /net/core/sock.c:2647
 [<     inline     >] SYSC_getsockopt /net/socket.c:1776
 [<ffffffff855f8ba2>] SyS_getsockopt+0x142/0x230 /net/socket.c:1758
 [<ffffffff8685cdc5>] entry_SYSCALL_64_fastpath+0x23/0xc6
Memory state around the buggy address:
 ffff880029c84d80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff880029c84e00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
> ffff880029c84e80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                              ^
 ffff880029c84f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff880029c84f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff

He also provided a syzkaller reproducer.

Issue is that ip6_datagram_recv_specific_ctl() expects to find IP6CB
data that was moved at a different place in tcp_v6_rcv()

This patch moves tcp_v6_restore_cb() up and calls it from
tcp_v6_do_rcv() when np->pktoptions is set.

Fixes: 971f10eca1 ("tcp: better TCP_SKB_CB layout to reduce cache line misses")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Baozeng Ding <sploving1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-13 11:07:34 -04:00
Nicolas Dichtel 7f92083eb5 vti6: flush x-netns xfrm cache when vti interface is removed
This is the same fix than commit a5d0dc810a ("vti: flush x-netns xfrm
cache when vti interface is removed")

This patch fixes a refcnt problem when a x-netns vti6 interface is removed:
unregister_netdevice: waiting for vti6_test to become free. Usage count = 1

Here is a script to reproduce the problem:

ip link set dev ntfp2 up
ip addr add dev ntfp2 2001::1/64
ip link add vti6_test type vti6 local 2001::1 remote 2001::2 key 1
ip netns add secure
ip link set vti6_test netns secure
ip netns exec secure ip link set vti6_test up
ip netns exec secure ip link s lo up
ip netns exec secure ip addr add dev vti6_test 2003::1/64
ip -6 xfrm policy add dir out tmpl src 2001::1 dst 2001::2 proto esp \
	   mode tunnel mark 1
ip -6 xfrm policy add dir in tmpl src 2001::2 dst 2001::1 proto esp \
	   mode tunnel mark 1
ip xfrm state add src 2001::1 dst 2001::2 proto esp spi 1 mode tunnel \
	   enc des3_ede 0x112233445566778811223344556677881122334455667788 mark 1
ip xfrm state add src 2001::2 dst 2001::1 proto esp spi 1 mode tunnel \
	   enc des3_ede 0x112233445566778811223344556677881122334455667788 mark 1
ip netns exec secure  ping6 -c 4 2003::2
ip netns del secure

CC: Lance Richardson <lrichard@redhat.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Lance Richardson <lrichard@redhat.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2016-10-11 10:46:44 +02:00
Maciej Żenczykowski cb4a4c691e ipv6 addrconf: disallow rtr_solicits < -1
This disallows setting /proc/sys/net/ipv6/conf/*/router_solicitations
to values below -1.

-1 continues to mean an unlimited number of retransmits.

Note: this depends on 'ipv6 addrconf: remove addrconf_sysctl_hop_limit()'

Signed-off-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-07 23:43:56 -04:00
Maciej Żenczykowski cb9e684e89 ipv6 addrconf: remove addrconf_sysctl_hop_limit()
This is an effective no-op in terms of user observable behaviour.

By preventing the overwrite of non-null extra1/extra2 fields
in addrconf_sysctl() we can enable the use of proc_dointvec_minmax().

This allows us to eliminate the constant min/max (1..255) trampoline
function that is addrconf_sysctl_hop_limit().

This is nice because it simplifies the code, and allows future
sysctls with constant min/max limits to also not require trampolines.

We still can't eliminate the trampoline for mtu because it isn't
actually a constant (it depends on other tunables of the device)
and thus requires at-write-time logic to enforce range.

Signed-off-by: Maciej Żenczykowski <maze@google.com>
Acked-by: Erik Kline <ek@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-02 23:48:13 -04:00
David S. Miller b50afd203a Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Three sets of overlapping changes.  Nothing serious.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-02 22:20:41 -04:00
Maciej Żenczykowski bd11f0741f ipv6 addrconf: implement RFC7559 router solicitation backoff
This implements:
  https://tools.ietf.org/html/rfc7559

Backoff is performed according to RFC3315 section 14:
  https://tools.ietf.org/html/rfc3315#section-14

We allow setting /proc/sys/net/ipv6/conf/*/router_solicitations
to a negative value meaning an unlimited number of retransmits,
and we make this the new default (inline with the RFC).

We also add a new setting:
  /proc/sys/net/ipv6/conf/*/router_solicitation_max_interval
defaulting to 1 hour (per RFC recommendation).

Signed-off-by: Maciej Żenczykowski <maze@google.com>
Acked-by: Erik Kline <ek@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30 01:54:28 -04:00
Jia He aca05671d5 ipv6: Remove useless parameter in __snmp6_fill_statsdev
The parameter items(is always ICMP6_MIB_MAX) is useless for __snmp6_fill_statsdev

Signed-off-by: Jia He <hejianet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30 01:50:45 -04:00
Jia He 4a4857b1c8 proc: Reduce cache miss in snmp6_seq_show
This is to use the generic interfaces snmp_get_cpu_field{,64}_batch to
aggregate the data by going through all the items of each cpu sequentially.

Signed-off-by: Jia He <hejianet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30 01:50:44 -04:00
Nikolay Aleksandrov 2cf750704b ipmr, ip6mr: fix scheduling while atomic and a deadlock with ipmr_get_route
Since the commit below the ipmr/ip6mr rtnl_unicast() code uses the portid
instead of the previous dst_pid which was copied from in_skb's portid.
Since the skb is new the portid is 0 at that point so the packets are sent
to the kernel and we get scheduling while atomic or a deadlock (depending
on where it happens) by trying to acquire rtnl two times.
Also since this is RTM_GETROUTE, it can be triggered by a normal user.

Here's the sleeping while atomic trace:
[ 7858.212557] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:620
[ 7858.212748] in_atomic(): 1, irqs_disabled(): 0, pid: 0, name: swapper/0
[ 7858.212881] 2 locks held by swapper/0/0:
[ 7858.213013]  #0:  (((&mrt->ipmr_expire_timer))){+.-...}, at: [<ffffffff810fbbf5>] call_timer_fn+0x5/0x350
[ 7858.213422]  #1:  (mfc_unres_lock){+.....}, at: [<ffffffff8161e005>] ipmr_expire_process+0x25/0x130
[ 7858.213807] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.8.0-rc7+ #179
[ 7858.213934] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[ 7858.214108]  0000000000000000 ffff88005b403c50 ffffffff813a7804 0000000000000000
[ 7858.214412]  ffffffff81a1338e ffff88005b403c78 ffffffff810a4a72 ffffffff81a1338e
[ 7858.214716]  000000000000026c 0000000000000000 ffff88005b403ca8 ffffffff810a4b9f
[ 7858.215251] Call Trace:
[ 7858.215412]  <IRQ>  [<ffffffff813a7804>] dump_stack+0x85/0xc1
[ 7858.215662]  [<ffffffff810a4a72>] ___might_sleep+0x192/0x250
[ 7858.215868]  [<ffffffff810a4b9f>] __might_sleep+0x6f/0x100
[ 7858.216072]  [<ffffffff8165bea3>] mutex_lock_nested+0x33/0x4d0
[ 7858.216279]  [<ffffffff815a7a5f>] ? netlink_lookup+0x25f/0x460
[ 7858.216487]  [<ffffffff8157474b>] rtnetlink_rcv+0x1b/0x40
[ 7858.216687]  [<ffffffff815a9a0c>] netlink_unicast+0x19c/0x260
[ 7858.216900]  [<ffffffff81573c70>] rtnl_unicast+0x20/0x30
[ 7858.217128]  [<ffffffff8161cd39>] ipmr_destroy_unres+0xa9/0xf0
[ 7858.217351]  [<ffffffff8161e06f>] ipmr_expire_process+0x8f/0x130
[ 7858.217581]  [<ffffffff8161dfe0>] ? ipmr_net_init+0x180/0x180
[ 7858.217785]  [<ffffffff8161dfe0>] ? ipmr_net_init+0x180/0x180
[ 7858.217990]  [<ffffffff810fbc95>] call_timer_fn+0xa5/0x350
[ 7858.218192]  [<ffffffff810fbbf5>] ? call_timer_fn+0x5/0x350
[ 7858.218415]  [<ffffffff8161dfe0>] ? ipmr_net_init+0x180/0x180
[ 7858.218656]  [<ffffffff810fde10>] run_timer_softirq+0x260/0x640
[ 7858.218865]  [<ffffffff8166379b>] ? __do_softirq+0xbb/0x54f
[ 7858.219068]  [<ffffffff816637c8>] __do_softirq+0xe8/0x54f
[ 7858.219269]  [<ffffffff8107a948>] irq_exit+0xb8/0xc0
[ 7858.219463]  [<ffffffff81663452>] smp_apic_timer_interrupt+0x42/0x50
[ 7858.219678]  [<ffffffff816625bc>] apic_timer_interrupt+0x8c/0xa0
[ 7858.219897]  <EOI>  [<ffffffff81055f16>] ? native_safe_halt+0x6/0x10
[ 7858.220165]  [<ffffffff810d64dd>] ? trace_hardirqs_on+0xd/0x10
[ 7858.220373]  [<ffffffff810298e3>] default_idle+0x23/0x190
[ 7858.220574]  [<ffffffff8102a20f>] arch_cpu_idle+0xf/0x20
[ 7858.220790]  [<ffffffff810c9f8c>] default_idle_call+0x4c/0x60
[ 7858.221016]  [<ffffffff810ca33b>] cpu_startup_entry+0x39b/0x4d0
[ 7858.221257]  [<ffffffff8164f995>] rest_init+0x135/0x140
[ 7858.221469]  [<ffffffff81f83014>] start_kernel+0x50e/0x51b
[ 7858.221670]  [<ffffffff81f82120>] ? early_idt_handler_array+0x120/0x120
[ 7858.221894]  [<ffffffff81f8243f>] x86_64_start_reservations+0x2a/0x2c
[ 7858.222113]  [<ffffffff81f8257c>] x86_64_start_kernel+0x13b/0x14a

Fixes: 2942e90050 ("[RTNETLINK]: Use rtnl_unicast() for rtnetlink unicasts")
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-25 23:41:39 -04:00
Pablo Neira Ayuso f20fbc0717 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Conflicts:
	net/netfilter/core.c
	net/netfilter/nf_tables_netdev.c

Resolve two conflicts before pull request for David's net-next tree:

1) Between c73c248490 ("netfilter: nf_tables_netdev: remove redundant
   ip_hdr assignment") from the net tree and commit ddc8b6027a
   ("netfilter: introduce nft_set_pktinfo_{ipv4, ipv6}_validate()").

2) Between e8bffe0cf9 ("net: Add _nf_(un)register_hooks symbols") and
   Aaron Conole's patches to replace list_head with single linked list.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-09-25 23:34:19 +02:00
Liping Zhang 8cb2a7d566 netfilter: nf_log: get rid of XT_LOG_* macros
nf_log is used by both nftables and iptables, so use XT_LOG_XXX macros
here is not appropriate. Replace them with NF_LOG_XXX.

Signed-off-by: Liping Zhang <liping.zhang@spreadtrum.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-09-25 23:16:45 +02:00