Andrey found a way to trigger the WARN_ON_ONCE(delta < len) in
skb_try_coalesce() using syzkaller and a filter attached to a TCP
socket over loopback interface.
I believe one issue with looped skbs is that tcp_trim_head() can end up
producing skb with under estimated truesize.
It hardly matters for normal conditions, since packets sent over
loopback are never truncated.
Bytes trimmed from skb->head should not change skb truesize, since
skb->head is not reallocated.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Upper layer GRO handlers can not handle IP fragments, so
exit GRO processing in this case.
This fixes ESP GRO because the packet must be reassembled
before we can decapsulate, otherwise we get authentication
failures.
It also aligns IPv4 to IPv6 where packets with fragmentation
headers are not passed to upper layer GRO handlers.
Fixes: 7785bba299 ("esp: Add a software GRO codepath")
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Always zero out ca_priv data in tcp_assign_congestion_control() so that
ca_priv data is cleared out during socket creation.
Also always zero out ca_priv data in tcp_reinit_congestion_control() so
that when cc algorithm is changed, ca_priv data is cleared out as well.
We should still zero out ca_priv data even in TCP_CLOSE state because
user could call connect() on AF_UNSPEC to disconnect the socket and
leave it in TCP_CLOSE state and later call setsockopt() to switch cc
algorithm on this socket.
Fixes: 2b0a8c9ee ("tcp: add CDG congestion control")
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Otherwise, UDP checksum offloads could corrupt ESP packets by attempting
to calculate UDP checksum when this inner UDP packet is already protected
by IPsec.
One way to reproduce this bug is to have a VM with virtio_net driver (UFO
set to ON in the guest VM); and then encapsulate all guest's Ethernet
frames in Geneve; and then further encrypt Geneve with IPsec. In this
case following symptoms are observed:
1. If using ixgbe NIC, then it will complain with following error message:
ixgbe 0000:01:00.1: partial checksum but l4 proto=32!
2. Receiving IPsec stack will drop all the corrupted ESP packets and
increase XfrmInStateProtoError counter in /proc/net/xfrm_stat.
3. iperf UDP test from the VM with packet sizes above MTU will not work at
all.
4. iperf TCP test from the VM will get ridiculously low performance because.
Signed-off-by: Ansis Atteka <aatteka@ovn.org>
Co-authored-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
David reported that doing the following:
ip li add red type vrf table 10
ip link set dev eth1 vrf red
ip addr add 127.0.0.1/8 dev red
ip link set dev eth1 up
ip li set red up
ping -c1 -w1 -I red 127.0.0.1
ip li del red
when either policy routing IP rules are present or the local table
lookup ip rule is before the l3mdev lookup results in a hang with
these messages:
unregister_netdevice: waiting for red to become free. Usage count = 1
The problem is caused by caching the dst used for sending the packet
out of the specified interface on a local route with a different
nexthop interface. Thus the dst could stay around until the route in
the table the lookup was done is deleted which may be never.
Address the problem by not forcing output device to be the l3mdev in
the flow's output interface if the lookup didn't use the l3mdev. This
then results in the dst using the right device according to the route.
Changes in v2:
- make the dev_out passed in by __ip_route_output_key_hash correct
instead of checking the nh dev if FLOWI_FLAG_SKIP_NH_OIF is set as
suggested by David.
Fixes: 5f02ce24c2 ("net: l3mdev: Allow the l3mdev to be a loopback")
Reported-by: David Ahern <dsa@cumulusnetworks.com>
Suggested-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: Robert Shearman <rshearma@brocade.com>
Acked-by: David Ahern <dsa@cumulusnetworks.com>
Tested-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Syzkaller reported a use-after-free in ip_recv_error at line
info->ipi_ifindex = skb->dev->ifindex;
This function is called on dequeue from the error queue, at which
point the device pointer may no longer be valid.
Save ifindex on enqueue in __skb_complete_tx_timestamp, when the
pointer is valid or NULL. Store it in temporary storage skb->cb.
It is safe to reference skb->dev here, as called from device drivers
or dev_queue_xmit. The exception is when called from tcp_ack_tstamp;
in that case it is NULL and ifindex is set to 0 (invalid).
Do not return a pktinfo cmsg if ifindex is 0. This maintains the
current behavior of not returning a cmsg if skb->dev was NULL.
On dequeue, the ipv4 path will cast from sock_exterr_skb to
in_pktinfo. Both have ifindex as their first element, so no explicit
conversion is needed. This is by design, introduced in commit
0b922b7a82 ("net: original ingress device index in PKTINFO"). For
ipv6 ip6_datagram_support_cmsg converts to in6_pktinfo.
Fixes: 829ae9d611 ("net-timestamp: allow reading recv cmsg on errqueue with origin tstamp")
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Similar to commit 87e9f03159
("ipv4: fix a potential deadlock in mcast getsockopt() path"),
there is a deadlock scenario for IP_ROUTER_ALERT too:
CPU0 CPU1
---- ----
lock(rtnl_mutex);
lock(sk_lock-AF_INET);
lock(rtnl_mutex);
lock(sk_lock-AF_INET);
Fix this by always locking RTNL first on all setsockopt() paths.
Note, after this patch ip_ra_lock is no longer needed either.
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contains Netfilter fixes for your net tree,
they are:
1) Missing TCP header sanity check in TCPMSS target, from Eric Dumazet.
2) Incorrect event message type for related conntracks created via
ctnetlink, from Liping Zhang.
3) Fix incorrect rcu locking when handling helpers from ctnetlink,
from Gao feng.
4) Fix missing rcu locking when updating helper, from Liping Zhang.
5) Fix missing read_lock_bh when iterating over list of device addresses
from TPROXY and redirect, also from Liping.
6) Fix crash when trying to dump expectations from conntrack with no
helper via ctnetlink, from Liping.
7) Missing RCU protection to expecation list update given ctnetlink
iterates over the list under rcu read lock side, from Liping too.
8) Don't dump autogenerated seed in nft_hash to userspace, this is
very confusing to the user, again from Liping.
9) Fix wrong conntrack netns module refcount in ipt_CLUSTERIP,
from Gao feng.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Current codes invoke wrongly nf_ct_netns_get in the destroy routine,
it should use nf_ct_netns_put, not nf_ct_netns_get.
It could cause some modules could not be unloaded.
Fixes: ecb2421b5d ("netfilter: add and use nf_ct_netns_get/put")
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Because TCP_MIB_OUTRSTS is an important count, so always increase it
whatever send it successfully or not.
Now move the increment of TCP_MIB_OUTRSTS to the top of
tcp_send_active_reset to make sure it is increased always even though
fail to alloc skb.
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The recent extension of F-RTO 89fe18e44 ("tcp: extend F-RTO
to catch more spurious timeouts") interacts badly with certain
broken middle-boxes. These broken boxes modify and falsely raise
the receive window on the ACKs. During a timeout induced recovery,
F-RTO would send new data packets to probe if the timeout is false
or not. Since the receive window is falsely raised, the receiver
would silently drop these F-RTO packets. The recovery would take N
(exponentially backoff) timeouts to repair N packet losses. A TCP
performance killer.
Due to this unfortunate situation, this patch removes this extension
to revert F-RTO back to the RFC specification.
Fixes: 89fe18e44f ("tcp: extend F-RTO to catch more spurious timeouts")
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
inet_rtm_getroute synthesizes a skeletal ICMP skb, which is passed to
ip_route_input when iif is given. If a multipath route is present for
the designated destination, ip_multipath_icmp_hash ends up being called,
which uses the source/destination addresses within the skb to calculate
a hash. However, those are not set in the synthetic skb, causing it to
return an arbitrary and incorrect result.
Instead, use UDP, which gets no such special treatment.
Signed-off-by: Florian Larysch <fl@n621.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently the reordering SNMP counters only increase if a connection
sees a higher degree then it has previously seen. It ignores if the
reordering degree is not greater than the default system threshold.
This significantly under-counts the number of reordering events
and falsely convey that reordering is rare on the network.
This patch properly and faithfully records the number of reordering
events detected by the TCP stack, just like the comment says "this
exciting event is worth to be remembered". Note that even so TCP
still under-estimate the actual reordering events because TCP
requires TS options or certain packet sequences to detect reordering
(i.e. ACKing never-retransmitted sequence in recovery or disordered
state).
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The lost retransmit SNMP stat is under-counting retransmission
that uses segment offloading. This patch fixes that so all
retransmission related SNMP counters are consistent.
Fixes: 10d3be5692 ("tcp-tso: do not split TSO packets at retransmit time")
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Markus Trippelsdorf reported that after commit dcb17d22e1 ("tcp: warn
on bogus MSS and try to amend it") the kernel started logging the
warning for a NIC driver that doesn't even support GRO.
It was diagnosed that it was possibly caused on connections that were
using TCP Timestamps but some packets lacked the Timestamps option. As
we reduce rcv_mss when timestamps are used, the lack of them would cause
the packets to be bigger than expected, although this is a valid case.
As this warning is more as a hint, getting a clean-cut on the
threshold is probably not worth the execution time spent on it. This
patch thus alleviates the false-positives with 2 quick checks: by
accounting for the entire TCP option space and also checking against the
interface MTU if it's available.
These changes, specially the MTU one, might mask some real positives,
though if they are really happening, it's possible that sooner or later
it will be triggered anyway.
Reported-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contains a rather large update with Netfilter
fixes, specifically targeted to incorrect RCU usage in several spots and
the userspace conntrack helper infrastructure (nfnetlink_cthelper),
more specifically they are:
1) expect_class_max is incorrect set via cthelper, as in kernel semantics
mandate that this represents the array of expectation classes minus 1.
Patch from Liping Zhang.
2) Expectation policy updates via cthelper are currently broken for several
reasons: This code allows illegal changes in the policy such as changing
the number of expeciation classes, it is leaking the updated policy and
such update occurs with no RCU protection at all. Fix this by adding a
new nfnl_cthelper_update_policy() that describes what is really legal on
the update path.
3) Fix several memory leaks in cthelper, from Jeffy Chen.
4) synchronize_rcu() is missing in the removal path of several modules,
this may lead to races since CPU may still be running on code that has
just gone. Also from Liping Zhang.
5) Don't use the helper hashtable from cthelper, it is not safe to walk
over those bits without the helper mutex. Fix this by introducing a
new independent list for userspace helpers. From Liping Zhang.
6) nf_ct_extend_unregister() needs synchronize_rcu() to make sure no
packets are walking on any conntrack extension that is gone after
module removal, again from Liping.
7) nf_nat_snmp may crash if we fail to unregister the helper due to
accidental leftover code, from Gao Feng.
8) Fix leak in nfnetlink_queue with secctx support, from Liping Zhang.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Our chosen ic_dev may be anywhere in our list of ic_devs, and we may
free it before attempting to close others. When we compare d->dev and
ic_dev->dev, we're potentially dereferencing memory returned to the
allocator. This causes KASAN to scream for each subsequent ic_dev we
check.
As there's a 1-1 mapping between ic_devs and netdevs, we can instead
compare d and ic_dev directly, which implicitly handles the !ic_dev
case, and avoids the use-after-free. The ic_dev pointer may be stale,
but we will not dereference it.
Original splat:
[ 6.487446] ==================================================================
[ 6.494693] BUG: KASAN: use-after-free in ic_close_devs+0xc4/0x154 at addr ffff800367efa708
[ 6.503013] Read of size 8 by task swapper/0/1
[ 6.507452] CPU: 5 PID: 1 Comm: swapper/0 Not tainted 4.11.0-rc3-00002-gda42158 #8
[ 6.514993] Hardware name: AppliedMicro Mustang/Mustang, BIOS 3.05.05-beta_rc Jan 27 2016
[ 6.523138] Call trace:
[ 6.525590] [<ffff200008094778>] dump_backtrace+0x0/0x570
[ 6.530976] [<ffff200008094d08>] show_stack+0x20/0x30
[ 6.536017] [<ffff200008bee928>] dump_stack+0x120/0x188
[ 6.541231] [<ffff20000856d5e4>] kasan_object_err+0x24/0xa0
[ 6.546790] [<ffff20000856d924>] kasan_report_error+0x244/0x738
[ 6.552695] [<ffff20000856dfec>] __asan_report_load8_noabort+0x54/0x80
[ 6.559204] [<ffff20000aae86ac>] ic_close_devs+0xc4/0x154
[ 6.564590] [<ffff20000aaedbac>] ip_auto_config+0x2ed4/0x2f1c
[ 6.570321] [<ffff200008084b04>] do_one_initcall+0xcc/0x370
[ 6.575882] [<ffff20000aa31de8>] kernel_init_freeable+0x5f8/0x6c4
[ 6.581959] [<ffff20000a16df00>] kernel_init+0x18/0x190
[ 6.587171] [<ffff200008084710>] ret_from_fork+0x10/0x40
[ 6.592468] Object at ffff800367efa700, in cache kmalloc-128 size: 128
[ 6.598969] Allocated:
[ 6.601324] PID = 1
[ 6.603427] save_stack_trace_tsk+0x0/0x418
[ 6.607603] save_stack_trace+0x20/0x30
[ 6.611430] kasan_kmalloc+0xd8/0x188
[ 6.615087] ip_auto_config+0x8c4/0x2f1c
[ 6.619002] do_one_initcall+0xcc/0x370
[ 6.622832] kernel_init_freeable+0x5f8/0x6c4
[ 6.627178] kernel_init+0x18/0x190
[ 6.630660] ret_from_fork+0x10/0x40
[ 6.634223] Freed:
[ 6.636233] PID = 1
[ 6.638334] save_stack_trace_tsk+0x0/0x418
[ 6.642510] save_stack_trace+0x20/0x30
[ 6.646337] kasan_slab_free+0x88/0x178
[ 6.650167] kfree+0xb8/0x478
[ 6.653131] ic_close_devs+0x130/0x154
[ 6.656875] ip_auto_config+0x2ed4/0x2f1c
[ 6.660875] do_one_initcall+0xcc/0x370
[ 6.664705] kernel_init_freeable+0x5f8/0x6c4
[ 6.669051] kernel_init+0x18/0x190
[ 6.672534] ret_from_fork+0x10/0x40
[ 6.676098] Memory state around the buggy address:
[ 6.680880] ffff800367efa600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[ 6.688078] ffff800367efa680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 6.695276] >ffff800367efa700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 6.702469] ^
[ 6.705952] ffff800367efa780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[ 6.713149] ffff800367efa800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[ 6.720343] ==================================================================
[ 6.727536] Disabling lock debugging due to kernel taint
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: David S. Miller <davem@davemloft.net>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: James Morris <jmorris@namei.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
In the commit 93557f53e1 ("netfilter: nf_conntrack: nf_conntrack snmp
helper"), the snmp_helper is replaced by nf_nat_snmp_hook. So the
snmp_helper is never registered. But it still tries to unregister the
snmp_helper, it could cause the panic.
Now remove the useless snmp_helper and the unregister call in the
error handler.
Fixes: 93557f53e1 ("netfilter: nf_conntrack: nf_conntrack snmp helper")
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Otherwise, another CPU may access the invalid pointer. For example:
CPU0 CPU1
- rcu_read_lock();
- pfunc = _hook_;
_hook_ = NULL; -
mod unload -
- pfunc(); // invalid, panic
- rcu_read_unlock();
So we must call synchronize_rcu() to wait the rcu reader to finish.
Also note, in nf_nat_snmp_basic_fini, synchronize_rcu() will be invoked
by later nf_conntrack_helper_unregister, but I'm inclined to add a
explicit synchronize_rcu after set the nf_nat_snmp_hook to NULL. Depend
on such obscure assumptions is not a good idea.
Last, in nfnetlink_cttimeout, we use kfree_rcu to free the time object,
so in cttimeout_exit, invoking rcu_barrier() is not necessary at all,
remove it too.
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
We got a report of yet another bug in ping
http://www.openwall.com/lists/oss-security/2017/03/24/6
->disconnect() is not called with socket lock held.
Fix this by acquiring ping rwlock earlier.
Thanks to Daniel, Alexander and Andrey for letting us know this problem.
Fixes: c319b4d76b ("net: ipv4: add IPPROTO_ICMP socket kind")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Daniel Jiang <danieljiang0415@gmail.com>
Reported-by: Solar Designer <solar@openwall.com>
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
icsk_ack.lrcvtime has a 0 value at socket creation time.
tcpi_last_data_recv can have bogus value if no payload is ever received.
This patch initializes icsk_ack.lrcvtime for active sessions
in tcp_finish_connect(), and for passive sessions in
tcp_create_openreq_child()
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexander reported a KMSAN splat caused by reads of uninitialized
field (tb_id_in) from user provided struct fib_result_nl
It turns out nl_fib_input() sanity tests on user input is a bit
wrong :
User can pretend nlh->nlmsg_len is big enough, but provide
at sendmsg() time a too small buffer.
Reported-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit b369e7fd41 ("tcp: make TCP_INFO more consistent") moved
lock_sock_fast() earlier in tcp_get_info()
This has the minor effect that jiffies value being sampled at the
beginning of tcp_get_info() is more likely to be off by one, and we
report big tcpi_last_data_sent values (like 0xFFFFFFFF).
Since we lock the socket, fetching tcp_time_stamp right before
doing the jiffies_to_msecs() calls is enough to remove these
wrong values.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contains Netfilter fixes for your net tree, a
rather large batch of fixes targeted to nf_tables, conntrack and bridge
netfilter. More specifically, they are:
1) Don't track fragmented packets if the socket option IP_NODEFRAG is set.
From Florian Westphal.
2) SCTP protocol tracker assumes that ICMP error messages contain the
checksum field, what results in packet drops. From Ying Xue.
3) Fix inconsistent handling of AH traffic from nf_tables.
4) Fix new bitmap set representation with big endian. Fix mismatches in
nf_tables due to incorrect big endian handling too. Both patches
from Liping Zhang.
5) Bridge netfilter doesn't honor maximum fragment size field, cap to
largest fragment seen. From Florian Westphal.
6) Fake conntrack entry needs to be aligned to 8 bytes since the 3 LSB
bits are now used to store the ctinfo. From Steven Rostedt.
7) Fix element comments with the bitmap set type. Revert the flush
field in the nft_set_iter structure, not required anymore after
fixing up element comments.
8) Missing error on invalid conntrack direction from nft_ct, also from
Liping Zhang.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
As Eric Dumazet pointed out this also needs to be fixed in IPv6.
v2: Contains the IPv6 tcp/Ipv6 dccp patches as well.
We have seen a few incidents lately where a dst_enty has been freed
with a dangling TCP socket reference (sk->sk_dst_cache) pointing to that
dst_entry. If the conditions/timings are right a crash then ensues when the
freed dst_entry is referenced later on. A Common crashing back trace is:
#8 [] page_fault at ffffffff8163e648
[exception RIP: __tcp_ack_snd_check+74]
.
.
#9 [] tcp_rcv_established at ffffffff81580b64
#10 [] tcp_v4_do_rcv at ffffffff8158b54a
#11 [] tcp_v4_rcv at ffffffff8158cd02
#12 [] ip_local_deliver_finish at ffffffff815668f4
#13 [] ip_local_deliver at ffffffff81566bd9
#14 [] ip_rcv_finish at ffffffff8156656d
#15 [] ip_rcv at ffffffff81566f06
#16 [] __netif_receive_skb_core at ffffffff8152b3a2
#17 [] __netif_receive_skb at ffffffff8152b608
#18 [] netif_receive_skb at ffffffff8152b690
#19 [] vmxnet3_rq_rx_complete at ffffffffa015eeaf [vmxnet3]
#20 [] vmxnet3_poll_rx_only at ffffffffa015f32a [vmxnet3]
#21 [] net_rx_action at ffffffff8152bac2
#22 [] __do_softirq at ffffffff81084b4f
#23 [] call_softirq at ffffffff8164845c
#24 [] do_softirq at ffffffff81016fc5
#25 [] irq_exit at ffffffff81084ee5
#26 [] do_IRQ at ffffffff81648ff8
Of course it may happen with other NIC drivers as well.
It's found the freed dst_entry here:
224 static bool tcp_in_quickack_mode(struct sock *sk)↩
225 {↩
226 ▹ const struct inet_connection_sock *icsk = inet_csk(sk);↩
227 ▹ const struct dst_entry *dst = __sk_dst_get(sk);↩
228 ↩
229 ▹ return (dst && dst_metric(dst, RTAX_QUICKACK)) ||↩
230 ▹ ▹ (icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong);↩
231 }↩
But there are other backtraces attributed to the same freed dst_entry in
netfilter code as well.
All the vmcores showed 2 significant clues:
- Remote hosts behind the default gateway had always been redirected to a
different gateway. A rtable/dst_entry will be added for that host. Making
more dst_entrys with lower reference counts. Making this more probable.
- All vmcores showed a postitive LockDroppedIcmps value, e.g:
LockDroppedIcmps 267
A closer look at the tcp_v4_err() handler revealed that do_redirect() will run
regardless of whether user space has the socket locked. This can result in a
race condition where the same dst_entry cached in sk->sk_dst_entry can be
decremented twice for the same socket via:
do_redirect()->__sk_dst_check()-> dst_release().
Which leads to the dst_entry being prematurely freed with another socket
pointing to it via sk->sk_dst_cache and a subsequent crash.
To fix this skip do_redirect() if usespace has the socket locked. Instead let
the redirect take place later when user space does not have the socket
locked.
The dccp/IPv6 code is very similar in this respect, so fixing it there too.
As Eric Garver pointed out the following commit now invalidates routes. Which
can set the dst->obsolete flag so that ipv4_dst_check() returns null and
triggers the dst_release().
Fixes: ceb3320610 ("ipv4: Kill routes during PMTU/redirect updates.")
Cc: Eric Garver <egarver@redhat.com>
Cc: Hannes Sowa <hsowa@redhat.com>
Signed-off-by: Jon Maxwell <jmaxwell37@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, there are two different methods to store an u16 integer to
the u32 data register. For example:
u32 *dest = ®s->data[priv->dreg];
1. *dest = 0; *(u16 *) dest = val_u16;
2. *dest = val_u16;
For method 1, the u16 value will be stored like this, either in
big-endian or little-endian system:
0 15 31
+-+-+-+-+-+-+-+-+-+-+-+-+
| Value | 0 |
+-+-+-+-+-+-+-+-+-+-+-+-+
For method 2, in little-endian system, the u16 value will be the same
as listed above. But in big-endian system, the u16 value will be stored
like this:
0 15 31
+-+-+-+-+-+-+-+-+-+-+-+-+
| 0 | Value |
+-+-+-+-+-+-+-+-+-+-+-+-+
So later we use "memcmp(®s->data[priv->sreg], data, 2);" to do
compare in nft_cmp, nft_lookup expr ..., method 2 will get the wrong
result in big-endian system, as 0~15 bits will always be zero.
For the similar reason, when loading an u16 value from the u32 data
register, we should use "*(u16 *) sreg;" instead of "(u16)*sreg;",
the 2nd method will get the wrong value in the big-endian system.
So introduce some wrapper functions to store/load an u8 or u16
integer to/from the u32 data register, and use them in the right
place.
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
commit c146066ab8 ("ipv4: Don't use ufo handling on later transformed
packets") and commit f89c56ce71 ("ipv6: Don't use ufo handling on
later transformed packets") added a check that 'rt->dst.header_len' isn't
zero in order to skip UFO, but it doesn't include IPcomp in transport mode
where it equals zero.
Packets, after payload compression, may not require further fragmentation,
and if original length exceeds MTU, later compressed packets will be
transmitted incorrectly. This can be reproduced with LTP udp_ipsec.sh test
on veth device with enabled UFO, MTU is 1500 and UDP payload is 2000:
* IPv4 case, offset is wrong + unnecessary fragmentation
udp_ipsec.sh -p comp -m transport -s 2000 &
tcpdump -ni ltp_ns_veth2
...
IP (tos 0x0, ttl 64, id 45203, offset 0, flags [+],
proto Compressed IP (108), length 49)
10.0.0.2 > 10.0.0.1: IPComp(cpi=0x1000)
IP (tos 0x0, ttl 64, id 45203, offset 1480, flags [none],
proto UDP (17), length 21) 10.0.0.2 > 10.0.0.1: ip-proto-17
* IPv6 case, sending small fragments
udp_ipsec.sh -6 -p comp -m transport -s 2000 &
tcpdump -ni ltp_ns_veth2
...
IP6 (flowlabel 0x6b9ba, hlim 64, next-header Compressed IP (108)
payload length: 37) fd00::2 > fd00::1: IPComp(cpi=0x1000)
IP6 (flowlabel 0x6b9ba, hlim 64, next-header Compressed IP (108)
payload length: 21) fd00::2 > fd00::1: IPComp(cpi=0x1000)
Fix it by checking 'rt->dst.xfrm' pointer to 'xfrm_state' struct, skip UFO
if xfrm is set. So the new check will include both cases: IPcomp and IPsec.
Fixes: c146066ab8 ("ipv4: Don't use ufo handling on later transformed packets")
Fixes: f89c56ce71 ("ipv6: Don't use ufo handling on later transformed packets")
Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Lockdep issues a circular dependency warning when AFS issues an operation
through AF_RXRPC from a context in which the VFS/VM holds the mmap_sem.
The theory lockdep comes up with is as follows:
(1) If the pagefault handler decides it needs to read pages from AFS, it
calls AFS with mmap_sem held and AFS begins an AF_RXRPC call, but
creating a call requires the socket lock:
mmap_sem must be taken before sk_lock-AF_RXRPC
(2) afs_open_socket() opens an AF_RXRPC socket and binds it. rxrpc_bind()
binds the underlying UDP socket whilst holding its socket lock.
inet_bind() takes its own socket lock:
sk_lock-AF_RXRPC must be taken before sk_lock-AF_INET
(3) Reading from a TCP socket into a userspace buffer might cause a fault
and thus cause the kernel to take the mmap_sem, but the TCP socket is
locked whilst doing this:
sk_lock-AF_INET must be taken before mmap_sem
However, lockdep's theory is wrong in this instance because it deals only
with lock classes and not individual locks. The AF_INET lock in (2) isn't
really equivalent to the AF_INET lock in (3) as the former deals with a
socket entirely internal to the kernel that never sees userspace. This is
a limitation in the design of lockdep.
Fix the general case by:
(1) Double up all the locking keys used in sockets so that one set are
used if the socket is created by userspace and the other set is used
if the socket is created by the kernel.
(2) Store the kern parameter passed to sk_alloc() in a variable in the
sock struct (sk_kern_sock). This informs sock_lock_init(),
sock_init_data() and sk_clone_lock() as to the lock keys to be used.
Note that the child created by sk_clone_lock() inherits the parent's
kern setting.
(3) Add a 'kern' parameter to ->accept() that is analogous to the one
passed in to ->create() that distinguishes whether kernel_accept() or
sys_accept4() was the caller and can be passed to sk_alloc().
Note that a lot of accept functions merely dequeue an already
allocated socket. I haven't touched these as the new socket already
exists before we get the parameter.
Note also that there are a couple of places where I've made the accepted
socket unconditionally kernel-based:
irda_accept()
rds_rcp_accept_one()
tcp_accept_from_sock()
because they follow a sock_create_kern() and accept off of that.
Whilst creating this, I noticed that lustre and ocfs don't create sockets
through sock_create_kern() and thus they aren't marked as for-kernel,
though they appear to be internal. I wonder if these should do that so
that they use the new set of lock keys.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The gso code of several tunnels type (gre and udp tunnels)
takes for granted that the skb->inner_protocol is properly
initialized and drops the packet elsewhere.
On the forwarding path no one is initializing such field,
so gro encapsulated packets are dropped on forward.
Since commit 3872035241 ("gre: Use inner_proto to obtain
inner header protocol"), this can be reproduced when the
encapsulated packets use gre as the tunneling protocol.
The issue happens also with vxlan and geneve tunnels since
commit 8bce6d7d0d ("udp: Generalize skb_udp_segment"), if the
forwarding host's ingress nic has h/w offload for such tunnel
and a vxlan/geneve device is configured on top of it, regardless
of the configured peer address and vni.
To address the issue, this change initialize the inner_protocol
field for encapsulated packets in both ipv4 and ipv6 gro complete
callbacks.
Fixes: 3872035241 ("gre: Use inner_proto to obtain inner header protocol")
Fixes: 8bce6d7d0d ("udp: Generalize skb_udp_segment")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Andrey reports syzkaller splat caused by
NF_CT_ASSERT(!ip_is_fragment(ip_hdr(skb)));
in ipv4 nat. But this assertion (and the comment) are wrong, this function
does see fragments when IP_NODEFRAG setsockopt is used.
As conntrack doesn't track packets without complete l4 header, only the
first fragment is tracked.
Because applying nat to first packet but not the rest makes no sense this
also turns off tracking of all fragments.
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Dmitry Vyukov reported a divide by 0 triggered by syzkaller, exploiting
tcp_disconnect() path that was never really considered and/or used
before syzkaller ;)
I was not able to reproduce the bug, but it seems issues here are the
three possible actions that assumed they would never trigger on a
listener.
1) tcp_write_timer_handler
2) tcp_delack_timer_handler
3) MTU reduction
Only IPv6 MTU reduction was properly testing TCP_CLOSE and TCP_LISTEN
states from tcp_v6_mtu_reduced()
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
1) Fix double-free in batman-adv, from Sven Eckelmann.
2) Fix packet stats for fast-RX path, from Joannes Berg.
3) Netfilter's ip_route_me_harder() doesn't handle request sockets
properly, fix from Florian Westphal.
4) Fix sendmsg deadlock in rxrpc, from David Howells.
5) Add missing RCU locking to transport hashtable scan, from Xin Long.
6) Fix potential packet loss in mlxsw driver, from Ido Schimmel.
7) Fix race in NAPI handling between poll handlers and busy polling,
from Eric Dumazet.
8) TX path in vxlan and geneve need proper RCU locking, from Jakub
Kicinski.
9) SYN processing in DCCP and TCP need to disable BH, from Eric
Dumazet.
10) Properly handle net_enable_timestamp() being invoked from IRQ
context, also from Eric Dumazet.
11) Fix crash on device-tree systems in xgene driver, from Alban Bedel.
12) Do not call sk_free() on a locked socket, from Arnaldo Carvalho de
Melo.
13) Fix use-after-free in netvsc driver, from Dexuan Cui.
14) Fix max MTU setting in bonding driver, from WANG Cong.
15) xen-netback hash table can be allocated from softirq context, so use
GFP_ATOMIC. From Anoob Soman.
16) Fix MAC address change bug in bgmac driver, from Hari Vyas.
17) strparser needs to destroy strp_wq on module exit, from WANG Cong.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (69 commits)
strparser: destroy workqueue on module exit
sfc: fix IPID endianness in TSOv2
sfc: avoid max() in array size
rds: remove unnecessary returned value check
rxrpc: Fix potential NULL-pointer exception
nfp: correct DMA direction in XDP DMA sync
nfp: don't tell FW about the reserved buffer space
net: ethernet: bgmac: mac address change bug
net: ethernet: bgmac: init sequence bug
xen-netback: don't vfree() queues under spinlock
xen-netback: keep a local pointer for vif in backend_disconnect()
netfilter: nf_tables: don't call nfnetlink_set_err() if nfnetlink_send() fails
netfilter: nft_set_rbtree: incorrect assumption on lower interval lookups
netfilter: nf_conntrack_sip: fix wrong memory initialisation
can: flexcan: fix typo in comment
can: usb_8dev: Fix memory leak of priv->cmd_msg_buffer
can: gs_usb: fix coding style
can: gs_usb: Don't use stack memory for USB transfers
ixgbe: Limit use of 2K buffers on architectures with 256B or larger cache lines
ixgbe: update the rss key on h/w, when ethtool ask for it
...
Pablo Neira Ayuso says:
====================
Netfilter fixes for net
The following patchset contains Netfilter fixes for your net tree,
they are:
1) Missing check for full sock in ip_route_me_harder(), from
Florian Westphal.
2) Incorrect sip helper structure initilization that breaks it when
several ports are used, from Christophe Leroy.
3) Fix incorrect assumption when looking up for matching with adjacent
intervals in the nft_set_rbtree.
4) Fix broken netlink event error reporting in nf_tables that results
in misleading ESRCH errors propagated to userspace listeners.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
tp->fastopen_req could potentially be double freed if a malicious
user does the following:
1. Enable TCP_FASTOPEN_CONNECT sockopt and do a connect() on the socket.
2. Call connect() with AF_UNSPEC to disconnect the socket.
3. Make this socket a listening socket by calling listen().
4. Accept incoming connections and generate child sockets. All child
sockets will get a copy of the pointer of fastopen_req.
5. Call close() on all sockets. fastopen_req will get freed multiple
times.
Fixes: 19f6d3f3c8 ("net/tcp-fastopen: Add new API support")
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix up affected files that include this signal functionality via sched.h.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We are going to split <linux/sched/clock.h> out of <linux/sched.h>, which
will have to be picked up from other headers and .c files.
Create a trivial placeholder <linux/sched/clock.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.
Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This will add stricter validating for RTA_MARK attribute.
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
1) Don't save TIPC header values before the header has been validated,
from Jon Paul Maloy.
2) Fix memory leak in RDS, from Zhu Yanjun.
3) We miss to initialize the UID in the flow key in some paths, from
Julian Anastasov.
4) Fix latent TOS masking bug in the routing cache removal from years
ago, also from Julian.
5) We forget to set the sockaddr port in sctp_copy_local_addr_list(),
fix from Xin Long.
6) Missing module ref count drop in packet scheduler actions, from
Roman Mashak.
7) Fix RCU annotations in rht_bucket_nested, from Herbert Xu.
8) Fix use after free which happens because L2TP's ipv4 support returns
non-zero values from it's backlog_rcv function which ipv4 interprets
as protocol values. Fix from Paul Hüber.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (35 commits)
qed: Don't use attention PTT for configuring BW
qed: Fix race with multiple VFs
l2tp: avoid use-after-free caused by l2tp_ip_backlog_recv
xfrm: provide correct dst in xfrm_neigh_lookup
rhashtable: Fix RCU dereference annotation in rht_bucket_nested
rhashtable: Fix use before NULL check in bucket_table_free
net sched actions: do not overwrite status of action creation.
rxrpc: Kernel calls get stuck in recvmsg
net sched actions: decrement module reference count after table flush.
lib: Allow compile-testing of parman
ipv6: check sk sk_type and protocol early in ip_mroute_set/getsockopt
sctp: set sin_port for addr param when checking duplicate address
net/mlx4_en: fix overflow in mlx4_en_init_timestamp()
netfilter: nft_set_bitmap: incorrect bitmap size
net: s2io: fix typo argumnet argument
net: vxge: fix typo argumnet argument
netfilter: nf_ct_expect: Change __nf_ct_expect_check() return value.
ipv4: mask tos for input route
ipv4: add missing initialization for flowi4_uid
lib: fix spelling mistake: "actualy" -> "actually"
...
inet_sk(skb->sk) is illegal in case skb is attached to request socket.
Fixes: ca6fb06518 ("tcp: attach SYNACK messages to request sockets instead of listener")
Reported by: Daniel J Blueman <daniel@quora.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Tested-by: Daniel J Blueman <daniel@quora.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Now that %z is standartised in C99 there is no reason to support %Z.
Unlike %L it doesn't even make format strings smaller.
Use BUILD_BUG_ON in a couple ATM drivers.
In case anyone didn't notice lib/vsprintf.o is about half of SLUB which
is in my opinion is quite an achievement. Hopefully this patch inspires
someone else to trim vsprintf.c more.
Link: http://lkml.kernel.org/r/20170103230126.GA30170@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Restore the lost masking of TOS in input route code to
allow ip rules to match it properly.
Problem [1] noticed by Shmulik Ladkani <shmulik.ladkani@gmail.com>
[1] http://marc.info/?t=137331755300040&r=1&w=2
Fixes: 89aef8921b ("ipv4: Delete routing cache.")
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
Avoid matching of random stack value for uid when rules
are looked up on input route or when RP filter is used.
Problem should affect only setups that use ip rules with
uid range.
Fixes: 622ec2c9d5 ("net: core: add UID to flows, rules, and routes")
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: David S. Miller <davem@davemloft.net>
We can get SYN with zero tsecr, don't apply offset in this case.
Fixes: ee684b6f28 ("tcp: send packets with a socket timestamp")
Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Found that when randomized tcp offsets are enabled (by default)
TCP client can still start new connections without them. Later,
if server does active close and re-uses sockets in TIME-WAIT
state, new SYN from client can be rejected on PAWS check inside
tcp_timewait_state_process(), because either tw_ts_recent or
rcv_tsval doesn't really have an offset set.
Here is how to reproduce it with LTP netstress tool:
netstress -R 1 &
netstress -H 127.0.0.1 -lr 1000000 -a1
[...]
< S seq 1956977072 win 43690 TS val 295618 ecr 459956970
> . ack 1956911535 win 342 TS val 459967184 ecr 1547117608
< R seq 1956911535 win 0 length 0
+1. < S seq 1956977072 win 43690 TS val 296640 ecr 459956970
> S. seq 657450664 ack 1956977073 win 43690 TS val 459968205 ecr 296640
Fixes: 95a22caee3 ("tcp: randomize tcp timestamp offsets for each connection")
Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit e70ac17165.
jtcp_rcv_established() is in fact called with hard irq being disabled.
Initial bug report from Ricardo Nabinger Sanchez [1] still needs
to be investigated, but does not look like a TCP bug.
[1] https://www.spinics.net/lists/netdev/msg420960.html
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: kernel test robot <xiaolong.ye@intel.com>
Cc: Ricardo Nabinger Sanchez <rnsanchez@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The skbs processed by ip_cmsg_recv() are not guaranteed to
be linear e.g. when sending UDP packets over loopback with
MSGMORE.
Using csum_partial() on [potentially] the whole skb len
is dangerous; instead be on the safe side and use skb_checksum().
Thanks to syzkaller team to detect the issue and provide the
reproducer.
v1 -> v2:
- move the variable declaration in a tighter scope
Fixes: ad6f939ab1 ("ip: Add offset parameter to ip_cmsg_recv")
Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
sk_page_frag_refill() allocates either a compound page or an order-0
page. We can use page_ref_inc() which is slightly faster than get_page()
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet