Even after commit 4785305c05 ("ipv6: use siphash in rt6_exception_hash()"),
an attacker can still use brute force to learn some secrets from a victim
linux host.
One way to defeat these attacks is to make the max depth of the hash
table bucket a random value.
Before this patch, each bucket of the hash table used to store exceptions
could contain 6 items under attack.
After the patch, each bucket would contains a random number of items,
between 6 and 10. The attacker can no longer infer secrets.
This is slightly increasing memory size used by the hash table,
we do not expect this to be a problem.
Following patch is dealing with the same issue in IPv4.
Fixes: 35732d01fe ("ipv6: introduce a hash table to store dst cache")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Keyu Man <kman001@ucr.edu>
Cc: Wei Wang <weiwan@google.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
Netfilter updates for net-next
The following patchset contains Netfilter updates for net-next:
1) Clean up and consolidate ct ecache infrastructure by merging ct and
expect notifiers, from Florian Westphal.
2) Missing counters and timestamp in nfnetlink_queue and _log conntrack
information.
3) Missing error check for xt_register_template() in iptables mangle,
as a incremental fix for the previous pull request, also from
Florian Westphal.
4) Add netfilter hooks for the SRv6 lightweigh tunnel driver, from
Ryoga Sato. The hooks are enabled via nf_hooks_lwtunnel sysctl
to make sure existing netfilter rulesets do not break. There is
a static key to disable the hooks by default.
The pktgen_bench_xmit_mode_netif_receive.sh shows no noticeable
impact in the seg6_input path for non-netfilter users: similar
numbers with and without this patch.
This is a sample of the perf report output:
11.67% kpktgend_0 [ipv6] [k] ipv6_get_saddr_eval
7.89% kpktgend_0 [ipv6] [k] __ipv6_addr_label
7.52% kpktgend_0 [ipv6] [k] __ipv6_dev_get_saddr
6.63% kpktgend_0 [kernel.vmlinux] [k] asm_exc_nmi
4.74% kpktgend_0 [ipv6] [k] fib6_node_lookup_1
3.48% kpktgend_0 [kernel.vmlinux] [k] pskb_expand_head
3.33% kpktgend_0 [ipv6] [k] ip6_rcv_core.isra.29
3.33% kpktgend_0 [ipv6] [k] seg6_do_srh_encap
2.53% kpktgend_0 [ipv6] [k] ipv6_dev_get_saddr
2.45% kpktgend_0 [ipv6] [k] fib6_table_lookup
2.24% kpktgend_0 [kernel.vmlinux] [k] ___cache_free
2.16% kpktgend_0 [ipv6] [k] ip6_pol_route
2.11% kpktgend_0 [kernel.vmlinux] [k] __ipv6_addr_type
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch introduces netfilter hooks for solving the problem that
conntrack couldn't record both inner flows and outer flows.
This patch also introduces a new sysctl toggle for enabling lightweight
tunnel netfilter hooks.
Signed-off-by: Ryoga Saito <contact@proelbtn.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The kernel provides a "/proc/sys/net/ipv6/conf/<iface>/mtu"
file, which can temporarily record the mtu value of the last
received RA message when the RA mtu value is lower than the
interface mtu, but this proc has following limitations:
(1) when the interface mtu (/sys/class/net/<iface>/mtu) is
updeated, mtu6 (/proc/sys/net/ipv6/conf/<iface>/mtu) will
be updated to the value of interface mtu;
(2) mtu6 (/proc/sys/net/ipv6/conf/<iface>/mtu) only affect
ipv6 connection, and not affect ipv4.
Therefore, when the mtu option is carried in the RA message,
there will be a problem that the user sometimes cannot obtain
RA mtu value correctly by reading mtu6.
After this patch set, if a RA message carries the mtu option,
you can send a netlink msg which nlmsg_type is RTM_GETLINK,
and then by parsing the attribute of IFLA_INET6_RA_MTU to
get the mtu value carried in the RA message received on the
inet6 device. In addition, you can also get a link notification
when ra_mtu is updated so it doesn't have to poll.
In this way, if the MTU values that the device receives from
the network in the PCO IPv4 and the RA IPv6 procedures are
different, the user can obtain the correct ipv6 ra_mtu value
and compare the value of ra_mtu and ipv4 mtu, then the device
can use the lower MTU value for both IPv4 and IPv6.
Signed-off-by: Rocco Yue <rocco.yue@mediatek.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20210827150412.9267-1-rocco.yue@mediatek.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
A group of security researchers brought to our attention
the weakness of hash function used in rt6_exception_hash()
Lets use siphash instead of Jenkins Hash, to considerably
reduce security risks.
Following patch deals with IPv4.
Fixes: 35732d01fe ("ipv6: introduce a hash table to store dst cache")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Keyu Man <kman001@ucr.edu>
Cc: Wei Wang <weiwan@google.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Acked-by: Wei Wang <weiwan@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
correct comments in set and get fn_sernum
Signed-off-by: zhang kai <zhangkaiheb@126.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Validate csum_start in gre_handle_offloads before we call _gre_xmit so
that we do not crash later when the csum_start value is used in the
lco_csum function call.
This patch deals with ipv6 code.
Fixes: Fixes: b05229f442 ("gre6: Cleanup GREv6 transmit path, call common
GRE functions")
Reported-by: syzbot+ff8e1b9f2f36481e2efc@syzkaller.appspotmail.com
Signed-off-by: Shreyansh Chouhan <chouhan.shreyansh630@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pablo Neira Ayuso says:
====================
Netfilter updates for net-next
The following patchset contains Netfilter updates for net-next:
1) Use nfnetlink_unicast() instead of netlink_unicast() in nft_compat.
2) Remove call to nf_ct_l4proto_find() in flowtable offload timeout
fixup.
3) CLUSTERIP registers ARP hook on demand, from Florian.
4) Use clusterip_net to store pernet warning, also from Florian.
5) Remove struct netns_xt, from Florian Westphal.
6) Enable ebtables hooks in initns on demand, from Florian.
7) Allow to filter conntrack netlink dump per status bits,
from Florian Westphal.
8) Register x_tables hooks in initns on demand, from Florian.
9) Remove queue_handler from per-netns structure, again from Florian.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
For historical reasons x_tables still register tables by default in the
initial namespace.
Only newly created net namespaces add the hook on demand.
This means that the init_net always pays hook cost, even if no filtering
rules are added (e.g. only used inside a single netns).
Note that the hooks are added even when 'iptables -L' is called.
This is because there is no way to tell 'iptables -A' and 'iptables -L'
apart at kernel level.
The only solution would be to register the table, but delay hook
registration until the first rule gets added (or policy gets changed).
That however means that counters are not hooked either, so 'iptables -L'
would always show 0-counters even when traffic is flowing which might be
unexpected.
This keeps table and hook registration consistent with what is already done
in non-init netns: first iptables(-save) invocation registers both table
and hooks.
This applies the same solution adopted for ebtables.
All tables register a template that contains the l3 family, the name
and a constructor function that is called when the initial table has to
be added.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
The 'if (dev)' statement already move into dev_{put , hold}, so remove
redundant if statements.
Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Signed-off-by: David S. Miller <davem@davemloft.net>
Replace IP6_SFLSIZE() with struct_size() helper in order to avoid any
potential type mistakes or integer overflows that, in the worst
scenario, could lead to heap overflows.
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
As presented last month in our "BIG TCP" talk at netdev 0x15,
we plan using IPv6 jumbograms.
One of the minor problem we talked about is the fact that
ip6_parse_tlv() is currently using tables to list known tlvs,
thus using potentially expensive indirect calls.
While we could mitigate this cost using macros from
indirect_call_wrapper.h, we also can get rid of the tables
and let the compiler emit optimized code.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Justin Iurman <justin.iurman@uliege.be>
Cc: Coco Li <lixiaoyan@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pass extack arg to validate_linkmsg and validate_link_af callbacks.
If a netlink attribute has a reject_message, use the extended ack
mechanism to carry the message back to user space.
Signed-off-by: Rocco Yue <rocco.yue@mediatek.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Unlike skb_realloc_headroom, new helper skb_expand_head
does not allocate a new skb if possible.
Additionally this patch replaces commonly used dereferencing with variables.
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Unlike skb_realloc_headroom, new helper skb_expand_head does not allocate
a new skb if possible.
Additionally this patch replaces commonly used dereferencing with variables.
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The various ipv4 and ipv6 tunnel drivers each implement a set
of 12 SIOCDEVPRIVATE commands for managing tunnels. These
all work correctly in compat mode.
Move them over to the new .ndo_siocdevprivate operation.
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: David Ahern <dsahern@kernel.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Decrease hop limit counter when deliver skb to ndp proxy.
Signed-off-by: Kangmin Park <l4stpr0gr4m@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When compiling without CONFIG_SYSCTL, this warning appears:
net/ipv6/addrconf.c:99:12: error: 'ioam6_if_id_max' defined but not used [-Werror=unused-variable]
99 | static u32 ioam6_if_id_max = U16_MAX;
| ^~~~~~~~~~~~~~~
cc1: all warnings being treated as errors
Simply moving the declaration of this variable under ...
#ifdef CONFIG_SYSCTL
... with other similar variables fixes the issue.
Fixes: 9ee11f0fff ("ipv6: ioam: Data plane support for Pre-allocated Trace")
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit d26796ae58 ("udp: check udp sock encap_type in __udp_lib_err")
added checks for encapsulated sockets but it broke cases when there is
no implementation of encap_err_lookup for encapsulation, i.e. ESP in
UDP encapsulation. Fix it by calling encap_err_lookup only if socket
implements this method otherwise treat it as legal socket.
Fixes: d26796ae58 ("udp: check udp sock encap_type in __udp_lib_err")
Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Replace ip6_dst_mtu_forward with ip6_dst_mtu_maybe_forward and
reuse this code in ip6_mtu. Actually these two functions were
almost duplicates, this change will simplify the maintaince of
mtu calculation code.
Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for the IOAM inline insertion (only for the host-to-host use case)
which is per-route configured with lightweight tunnels. The target is iproute2
and the patch is ready. It will be posted as soon as this patchset is merged.
Here is an overview:
$ ip -6 ro ad fc00::1/128 encap ioam6 trace type 0x800000 ns 1 size 12 dev eth0
This example configures an IOAM Pre-allocated Trace option attached to the
fc00::1/128 prefix. The IOAM namespace (ns) is 1, the size of the pre-allocated
trace data block is 12 octets (size) and only the first IOAM data (bit 0:
hop_limit + node id) is included in the trace (type) represented as a bitfield.
The reason why the in-transit (IPv6-in-IPv6 encapsulation) use case is not
implemented is explained on the patchset cover.
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add Generic Netlink commands to allow userspace to configure IOAM
namespaces and schemas. The target is iproute2 and the patch is ready.
It will be posted as soon as this patchset is merged. Here is an overview:
$ ip ioam
Usage: ip ioam { COMMAND | help }
ip ioam namespace show
ip ioam namespace add ID [ data DATA32 ] [ wide DATA64 ]
ip ioam namespace del ID
ip ioam schema show
ip ioam schema add ID DATA
ip ioam schema del ID
ip ioam namespace set ID schema { ID | none }
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implement support for processing the IOAM Pre-allocated Trace with IPv6,
see [1] and [2]. Introduce a new IPv6 Hop-by-Hop TLV option, see IANA [3].
A new per-interface sysctl is introduced. The value is a boolean to accept (=1)
or ignore (=0, by default) IPv6 IOAM options on ingress for an interface:
- net.ipv6.conf.XXX.ioam6_enabled
Two other sysctls are introduced to define IOAM IDs, represented by an integer.
They are respectively per-namespace and per-interface:
- net.ipv6.ioam6_id
- net.ipv6.conf.XXX.ioam6_id
The value of the first one represents the IOAM ID of the node itself (u32; max
and default value = U32_MAX>>8, due to hop limit concatenation) while the other
represents the IOAM ID of an interface (u16; max and default value = U16_MAX).
Each "ioam6_id" sysctl has a "_wide" equivalent:
- net.ipv6.ioam6_id_wide
- net.ipv6.conf.XXX.ioam6_id_wide
The value of the first one represents the wide IOAM ID of the node itself (u64;
max and default value = U64_MAX>>8, due to hop limit concatenation) while the
other represents the wide IOAM ID of an interface (u32; max and default value
= U32_MAX).
The use of short and wide equivalents is not exclusive, a deployment could
choose to leverage both. For example, net.ipv6.conf.XXX.ioam6_id (short format)
could be an identifier for a physical interface, whereas
net.ipv6.conf.XXX.ioam6_id_wide (wide format) could be an identifier for a
logical sub-interface. Documentation about new sysctls is provided at the end
of this patchset.
Two relativistic hash tables are used: one for IOAM namespaces, the other for
IOAM schemas. A namespace can only have a single active schema and a schema
can only be attached to a single namespace (1:1 relationship).
[1] https://tools.ietf.org/html/draft-ietf-ippm-ioam-ipv6-options
[2] https://tools.ietf.org/html/draft-ietf-ippm-ioam-data
[3] https://www.iana.org/assignments/ipv6-parameters/ipv6-parameters.xhtml#ipv6-parameters-2
Signed-off-by: Justin Iurman <justin.iurman@uliege.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
While running the self-tests on a KASAN enabled kernel, I observed a
slab-out-of-bounds splat very similar to the one reported in
commit 821bbf79fe ("ipv6: Fix KASAN: slab-out-of-bounds Read in
fib6_nh_flush_exceptions").
We additionally need to take care of fib6_metrics initialization
failure when the caller provides an nh.
The fix is similar, explicitly free the route instead of calling
fib6_info_release on a half-initialized object.
Fixes: f88d8ea67f ("ipv6: Plumb support for nexthop object in a fib6_info")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Author: Andrey Ryabinin <aryabinin@virtuozzo.com>
The size of the ip_tunnel_prl structs allocation is controllable from
user-space, thus it's better to avoid spam in dmesg if allocation failed.
Also add __GFP_ACCOUNT as this is a good candidate for per-memcg
accounting. Allocation is temporary and limited by 4GB.
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
An netadmin inside container can use 'ip a a' and 'ip r a'
to assign a large number of ipv4/ipv6 addresses and routing entries
and force kernel to allocate megabytes of unaccounted memory
for long-lived per-netdevice related kernel objects:
'struct in_ifaddr', 'struct inet6_ifaddr', 'struct fib6_node',
'struct rt6_info', 'struct fib_rules' and ip_fib caches.
These objects can be manually removed, though usually they lives
in memory till destroy of its net namespace.
It makes sense to account for them to restrict the host's memory
consumption from inside the memcg-limited container.
One of such objects is the 'struct fib6_node' mostly allocated in
net/ipv6/route.c::__ip6_ins_rt() inside the lock_bh()/unlock_bh() section:
write_lock_bh(&table->tb6_lock);
err = fib6_add(&table->tb6_root, rt, info, mxc);
write_unlock_bh(&table->tb6_lock);
In this case it is not enough to simply add SLAB_ACCOUNT to corresponding
kmem cache. The proper memory cgroup still cannot be found due to the
incorrect 'in_interrupt()' check used in memcg_kmem_bypass().
Obsoleted in_interrupt() does not describe real execution context properly.
>From include/linux/preempt.h:
The following macros are deprecated and should not be used in new code:
in_interrupt() - We're in NMI,IRQ,SoftIRQ context or have BH disabled
To verify the current execution context new macro should be used instead:
in_task() - We're in task context
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The local variable "struct net *net" in the two functions of
inet6_rtm_getaddr() and inet6_dump_addr() are actually useless,
so remove them.
Signed-off-by: Rocco Yue <rocco.yue@mediatek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When TEE target mirrors traffic to another interface, sk_buff may
not have enough headroom to be processed correctly.
ip_finish_output2() detect this situation for ipv4 and allocates
new skb with enogh headroom. However ipv6 lacks this logic in
ip_finish_output2 and it leads to skb_under_panic:
skbuff: skb_under_panic: text:ffffffffc0866ad4 len:96 put:24
head:ffff97be85e31800 data:ffff97be85e317f8 tail:0x58 end:0xc0 dev:gre0
------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:110!
invalid opcode: 0000 [#1] SMP PTI
CPU: 2 PID: 393 Comm: kworker/2:2 Tainted: G OE 5.13.0 #13
Hardware name: Virtuozzo KVM, BIOS 1.11.0-2.vz7.4 04/01/2014
Workqueue: ipv6_addrconf addrconf_dad_work
RIP: 0010:skb_panic+0x48/0x4a
Call Trace:
skb_push.cold.111+0x10/0x10
ipgre_header+0x24/0xf0 [ip_gre]
neigh_connected_output+0xae/0xf0
ip6_finish_output2+0x1a8/0x5a0
ip6_output+0x5c/0x110
nf_dup_ipv6+0x158/0x1000 [nf_dup_ipv6]
tee_tg6+0x2e/0x40 [xt_TEE]
ip6t_do_table+0x294/0x470 [ip6_tables]
nf_hook_slow+0x44/0xc0
nf_hook.constprop.34+0x72/0xe0
ndisc_send_skb+0x20d/0x2e0
ndisc_send_ns+0xd1/0x210
addrconf_dad_work+0x3c8/0x540
process_one_work+0x1d1/0x370
worker_thread+0x30/0x390
kthread+0x116/0x130
ret_from_fork+0x22/0x30
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit e05a90ec9e ("net: reflect mark on tcp syn ack packets")
fixed IPv4 only.
This part is for the IPv6 side.
Fixes: e05a90ec9e ("net: reflect mark on tcp syn ack packets")
Signed-off-by: Alexander Ovechkin <ovov@yandex-team.ru>
Acked-by: Dmitry Yakunin <zeil@yandex-team.ru>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
While TCP stack scales reasonably well, there is still one part that
can be used to DDOS it.
IPv6 Packet too big messages have to lookup/insert a new route,
and if abused by attackers, can easily put hosts under high stress,
with many cpus contending on a spinlock while one is stuck in fib6_run_gc()
ip6_protocol_deliver_rcu()
icmpv6_rcv()
icmpv6_notify()
tcp_v6_err()
tcp_v6_mtu_reduced()
inet6_csk_update_pmtu()
ip6_rt_update_pmtu()
__ip6_rt_update_pmtu()
ip6_rt_cache_alloc()
ip6_dst_alloc()
dst_alloc()
ip6_dst_gc()
fib6_run_gc()
spin_lock_bh() ...
Some of our servers have been hit by malicious ICMPv6 packets
trying to _increase_ the MTU/MSS of TCP flows.
We believe these ICMPv6 packets are a result of a bug in one ISP stack,
since they were blindly sent back for _every_ (small) packet sent to them.
These packets are for one TCP flow:
09:24:36.266491 IP6 Addr1 > Victim ICMP6, packet too big, mtu 1460, length 1240
09:24:36.266509 IP6 Addr1 > Victim ICMP6, packet too big, mtu 1460, length 1240
09:24:36.316688 IP6 Addr1 > Victim ICMP6, packet too big, mtu 1460, length 1240
09:24:36.316704 IP6 Addr1 > Victim ICMP6, packet too big, mtu 1460, length 1240
09:24:36.608151 IP6 Addr1 > Victim ICMP6, packet too big, mtu 1460, length 1240
TCP stack can filter some silly requests :
1) MTU below IPV6_MIN_MTU can be filtered early in tcp_v6_err()
2) tcp_v6_mtu_reduced() can drop requests trying to increase current MSS.
This tests happen before the IPv6 routing stack is entered, thus
removing the potential contention and route exhaustion.
Note that IPv6 stack was performing these checks, but too late
(ie : after the route has been added, and after the potential
garbage collect war)
v2: fix typo caught by Martin, thanks !
v3: exports tcp_mtu_to_mss(), caught by David, thanks !
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Maciej Żenczykowski <maze@google.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The goal of commit df789fe752 ("ipv6: Provide ipv6 version of
"disable_policy" sysctl") was to have the disable_policy from ipv4
available on ipv6.
However, it's not exactly the same mechanism. On IPv4, all packets coming
from an interface, which has disable_policy set, bypass the policy check.
For ipv6, this is done only for local packets, ie for packets destinated to
an address configured on the incoming interface.
Let's align ipv6 with ipv4 so that the 'disable_policy' sysctl has the same
effect for both protocols.
My first approach was to create a new kind of route cache entries, to be
able to set DST_NOPOLICY without modifying routes. This would have added a
lot of code. Because the local delivery path is already handled, I choose
to focus on the forwarding path to minimize code churn.
Fixes: df789fe752 ("ipv6: Provide ipv6 version of "disable_policy" sysctl")
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
While tp->mtu_info is read while socket is owned, the write
sides happen from err handlers (tcp_v[46]_mtu_reduced)
which only own the socket spinlock.
Fixes: 563d34d057 ("tcp: dont drop MTU reduction indications")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 628a5c5618 ("[INET]: Add IP(V6)_PMTUDISC_RPOBE") introduced
ip6_skb_dst_mtu with return value of signed int which is inconsistent
with actually returned values. Also 2 users of this function actually
assign its value to unsigned int variable and only __xfrm6_output
assigns result of this function to signed variable but actually uses
as unsigned in further comparisons and calls. Change this function
to return unsigned int value.
Fixes: 628a5c5618 ("[INET]: Add IP(V6)_PMTUDISC_RPOBE")
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
Trivial conflict in net/netfilter/nf_tables_api.c.
Duplicate fix in tools/testing/selftests/net/devlink_port_split.py
- take the net-next version.
skmsg, and L4 bpf - keep the bpf code but remove the flags
and err params.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This patch introduces a function wrapper to call the sk_error_report
callback. That will prepare to add additional handling whenever
sk_error_report is called, for example to trace socket errors.
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch builds off of commit 2b246b2569
and adds functionality to respond to ICMPV6 PROBE requests.
Add icmp_build_probe function to construct PROBE requests for both
ICMPV4 and ICMPV6.
Modify icmpv6_rcv to detect ICMPV6 PROBE messages and call the
icmpv6_echo_reply handler.
Modify icmpv6_echo_reply to build a PROBE response message based on the
queried interface.
This patch has been tested using a branch of the iputils git repo which can
be found here: https://github.com/Juniper-Clinic-2020/iputils/tree/probe-request
Signed-off-by: Andreas Roeseler <andreas.a.roeseler@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
/klassert/ipsec-next
Steffen Klassert says:
====================
pull request (net-next): ipsec-next 2021-06-28
1) Remove an unneeded error assignment in esp4_gro_receive().
From Yang Li.
2) Add a new byseq state hashtable to find acquire states faster.
From Sabrina Dubroca.
3) Remove some unnecessary variables in pfkey_create().
From zuoqilin.
4) Remove the unused description from xfrm_type struct.
From Florian Westphal.
5) Fix a spelling mistake in the comment of xfrm_state_ok().
From gushengxian.
6) Replace hdr_off indirections by a small helper function.
From Florian Westphal.
7) Remove xfrm4_output_finish and xfrm6_output_finish declarations,
they are not used anymore.From Antony Antony.
8) Remove xfrm replay indirections.
From Florian Westphal.
Please pull or let me know if there are problems.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Reset the mac_header pointer even when the tunnel transports only L3
data (in the ARPHRD_ETHER case, this is already done by eth_type_trans).
This prevents other parts of the stack from mistakenly accessing the
outer header after the packet has been decapsulated.
In practice, this allows to push an Ethernet header to ipip6, ip6ip6,
mplsip6 or ip6gre packets and redirect them to an Ethernet device:
$ tc filter add dev ip6tnl0 ingress matchall \
action vlan push_eth dst_mac 00:00:5e:00:53:01 \
src_mac 00:00:5e:00:53:00 \
action mirred egress redirect dev eth0
Without this patch, push_eth refuses to add an ethernet header because
the skb appears to already have a MAC header.
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Even though sit transports L3 data (IPv6, IPv4 or MPLS) packets, it
needs to reset the mac_header pointer, so that other parts of the stack
don't mistakenly access the outer header after the packet has been
decapsulated. There are two rx handlers to modify: ipip6_rcv() for the
ip6ip mode and sit_tunnel_rcv() which is used to re-implement the ipip
and mplsip modes of ipip.ko.
This allows to push an Ethernet header to sit packets and redirect
them to an Ethernet device:
$ tc filter add dev sit0 ingress matchall \
action vlan push_eth dst_mac 00:00:5e:00:53:01 \
src_mac 00:00:5e:00:53:00 \
action mirred egress redirect dev eth0
Without this patch, push_eth refuses to add an ethernet header because
the skb appears to already have a MAC header.
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
First problem is that optlen is fetched without checking
there is more than one byte to parse.
Fix this by taking care of IPV6_TLV_PAD1 before
fetching optlen (under appropriate sanity checks against len)
Second problem is that IPV6_TLV_PADN checks of zero
padding are performed before the check of remaining length.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Fixes: c1412fce7e ("net/ipv6/exthdrs.c: Strict PadN option checking")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Dave observed number of machines hitting OOM on the UDP send
path. The workload seems to be sending large UDP packets over
loopback. Since loopback has MTU of 64k kernel will try to
allocate an skb with up to 64k of head space. This has a good
chance of failing under memory pressure. What's worse if
the message length is <32k the allocation may trigger an
OOM killer.
This is entirely avoidable, we can use an skb with page frags.
af_unix solves a similar problem by limiting the head
length to SKB_MAX_ALLOC. This seems like a good and simple
approach. It means that UDP messages > 16kB will now
use fragments if underlying device supports SG, if extra
allocator pressure causes regressions in real workloads
we can switch to trying the large allocation first and
falling back.
v4: pre-calculate all the additions to alloclen so
we can be sure it won't go over order-2
Reported-by: Dave Jones <dsj@fb.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
I see no reason why max_dst_opts_cnt and max_hbh_opts_cnt
are fetched from the initial net namespace.
The other sysctls (max_dst_opts_len & max_hbh_opts_len)
are in fact already using the current ns.
Note: it is not clear why ipv6_destopt_rcv() use two ways to
get to the netns :
1) dev_net(dst->dev)
Originally used to increment IPSTATS_MIB_INHDRERRORS
2) dev_net(skb->dev)
Tom used this variant in his patch.
Maybe this calls to use ipv6_skb_net() instead ?
Fixes: 47d3d7ac65 ("ipv6: Implement limits on Hop-by-Hop and Destination options")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <tom@quantonium.net>
Cc: Coco Li <lixiaoyan@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Steffen Klassert says:
====================
pull request (net): ipsec 2021-06-23
1) Don't return a mtu smaller than 1280 on IPv6 pmtu discovery.
From Sabrina Dubroca
2) Fix seqcount rcu-read side in xfrm_policy_lookup_bytype
for the PREEMPT_RT case. From Varad Gautam.
3) Remove a repeated declaration of xfrm_parse_spi.
From Shaokun Zhang.
4) IPv4 beet mode can't handle fragments, but IPv6 does.
commit 68dc022d04 ("xfrm: BEET mode doesn't support
fragments for inner packets") handled IPv4 and IPv6
the same way. Relax the check for IPv6 because fragments
are possible here. From Xin Long.
5) Memory allocation failures are not reported for
XFRMA_ENCAP and XFRMA_COADDR in xfrm_state_construct.
Fix this by moving both cases in front of the function.
6) Fix a missing initialization in the xfrm offload fallback
fail case for bonding devices. From Ayush Sawal.
Please pull or let me know if there are problems.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
