Commit Graph

840 Commits

Author SHA1 Message Date
Paul Blakey
35d39fecbc net/sched: Enable tc skb ext allocation on chain miss only when needed
Currently tc skb extension is used to send miss info from
tc to ovs datapath module, and driver to tc. For the tc to ovs
miss it is currently always allocated even if it will not
be used by ovs datapath (as it depends on a requested feature).

Export the static key which is used by openvswitch module to
guard this code path as well, so it will be skipped if ovs
datapath doesn't need it. Enable this code path once
ovs datapath needs it.

Signed-off-by: Paul Blakey <paulb@nvidia.com>
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-05 10:12:53 +00:00
Jakub Kicinski
8aaaf2f3af Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Merge in fixes directly in prep for the 5.17 merge window.
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-09 17:00:17 -08:00
Paul Blakey
6f022c2ddb net: openvswitch: Fix ct_state nat flags for conns arriving from tc
Netfilter conntrack maintains NAT flags per connection indicating
whether NAT was configured for the connection. Openvswitch maintains
NAT flags on the per packet flow key ct_state field, indicating
whether NAT was actually executed on the packet.

When a packet misses from tc to ovs the conntrack NAT flags are set.
However, NAT was not necessarily executed on the packet because the
connection's state might still be in NEW state. As such, openvswitch
wrongly assumes that NAT was executed and sets an incorrect flow key
NAT flags.

Fix this, by flagging to openvswitch which NAT was actually done in
act_ct via tc_skb_ext and tc_skb_cb to the openvswitch module, so
the packet flow key NAT flags will be correctly set.

Fixes: b57dc7c13e ("net/sched: Introduce action ct")
Signed-off-by: Paul Blakey <paulb@nvidia.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://lore.kernel.org/r/20220106153804.26451-1-paulb@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-09 16:24:12 -08:00
Jakub Kicinski
77bbcb60f7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for net-next. This
includes one patch to update ovs and act_ct to use nf_ct_put() instead
of nf_conntrack_put().

1) Add netns_tracker to nfnetlink_log and masquerade, from Eric Dumazet.

2) Remove redundant rcu read-size lock in nf_tables packet path.

3) Replace BUG() by WARN_ON_ONCE() in nft_payload.

4) Consolidate rule verdict tracing.

5) Replace WARN_ON() by WARN_ON_ONCE() in nf_tables core.

6) Make counter support built-in in nf_tables.

7) Add new field to conntrack object to identify locally generated
   traffic, from Florian Westphal.

8) Prevent NAT from shadowing well-known ports, from Florian Westphal.

9) Merge nf_flow_table_{ipv4,ipv6} into nf_flow_table_inet, also from
   Florian.

10) Remove redundant pointer in nft_pipapo AVX2 support, from Colin Ian King.

11) Replace opencoded max() in conntrack, from Jiapeng Chong.

12) Update conntrack to use refcount_t API, from Florian Westphal.

13) Move ip_ct_attach indirection into the nf_ct_hook structure.

14) Constify several pointer object in the netfilter codebase,
    from Florian Westphal.

15) Tree-wide replacement of nf_conntrack_put() by nf_ct_put(), also
    from Florian.

16) Fix egress splat due to incorrect rcu notation, from Florian.

17) Move stateful fields of connlimit, last, quota, numgen and limit
    out of the expression data area.

18) Build a blob to represent the ruleset in nf_tables, this is a
    requirement of the new register tracking infrastructure.

19) Add NFT_REG32_NUM to define the maximum number of 32-bit registers.

20) Add register tracking infrastructure to skip redundant
    store-to-register operations, this includes support for payload,
    meta and bitwise expresssions.

* git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next: (32 commits)
  netfilter: nft_meta: cancel register tracking after meta update
  netfilter: nft_payload: cancel register tracking after payload update
  netfilter: nft_bitwise: track register operations
  netfilter: nft_meta: track register operations
  netfilter: nft_payload: track register operations
  netfilter: nf_tables: add register tracking infrastructure
  netfilter: nf_tables: add NFT_REG32_NUM
  netfilter: nf_tables: add rule blob layout
  netfilter: nft_limit: move stateful fields out of expression data
  netfilter: nft_limit: rename stateful structure
  netfilter: nft_numgen: move stateful fields out of expression data
  netfilter: nft_quota: move stateful fields out of expression data
  netfilter: nft_last: move stateful fields out of expression data
  netfilter: nft_connlimit: move stateful fields out of expression data
  netfilter: egress: avoid a lockdep splat
  net: prefer nf_ct_put instead of nf_conntrack_put
  netfilter: conntrack: avoid useless indirection during conntrack destruction
  netfilter: make function op structures const
  netfilter: core: move ip_ct_attach indirection to struct nf_ct_hook
  netfilter: conntrack: convert to refcount_t api
  ...
====================

Link: https://lore.kernel.org/r/20220109231640.104123-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-09 15:59:23 -08:00
Florian Westphal
408bdcfce8 net: prefer nf_ct_put instead of nf_conntrack_put
Its the same as nf_conntrack_put(), but without the
need for an indirect call.  The downside is a module dependency on
nf_conntrack, but all of these already depend on conntrack anyway.

Cc: Paul Blakey <paulb@mellanox.com>
Cc: dev@openvswitch.org
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-01-09 23:30:14 +01:00
Florian Westphal
7197743776 netfilter: conntrack: convert to refcount_t api
Convert nf_conn reference counting from atomic_t to refcount_t based api.
refcount_t api provides more runtime sanity checks and will warn on
certain constructs, e.g. refcount_inc() on a zero reference count, which
usually indicates use-after-free.

For this reason template allocation is changed to init the refcount to
1, the subsequenct add operations are removed.

Likewise, init_conntrack() is changed to set the initial refcount to 1
instead refcount_inc().

This is safe because the new entry is not (yet) visible to other cpus.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-01-09 23:30:13 +01:00
Paul Blakey
b702436a51 net: openvswitch: Fill act ct extension
To give drivers the originating device information for optimized
connection tracking offload, fill in act ct extension with
ifindex from skb.

Signed-off-by: Paul Blakey <paulb@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-04 12:12:56 +00:00
Jakub Kicinski
8b3f913322 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
include/net/sock.h
  commit 8f905c0e73 ("inet: fully convert sk->sk_rx_dst to RCU rules")
  commit 43f51df417 ("net: move early demux fields close to sk_refcnt")
  https://lore.kernel.org/all/20211222141641.0caa0ab3@canb.auug.org.au/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-23 16:09:58 -08:00
Paul Blakey
635d448a1c net: openvswitch: Fix matching zone id for invalid conns arriving from tc
Zone id is not restored if we passed ct and ct rejected the connection,
as there is no ct info on the skb.

Save the zone from tc skb cb to tc skb extension and pass it on to
ovs, use that info to restore the zone id for invalid connections.

Fixes: d29334c15d ("net/sched: act_api: fix miss set post_ct for ovs after do conntrack in act_ct")
Signed-off-by: Paul Blakey <paulb@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-17 18:06:36 -08:00
Eric Dumazet
e7c8ab8419 openvswitch: add net device refcount tracker to struct vport
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-07 20:45:00 -08:00
Xu Wang
98fa41d627 net: openvswitch: Remove redundant if statements
The 'if (dev)' statement already move into dev_{put , hold}, so remove
redundant if statements.

Signed-off-by: Xu Wang <vulab@iscas.ac.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-02 13:08:19 +00:00
Mianhan Liu
a1554c0026 include/linux/mm.h: move nr_free_buffer_pages from swap.h to mm.h
nr_free_buffer_pages could be exposed through mm.h instead of swap.h.
The advantage of this change is that it can reduce the obsolete
includes.  For example, net/ipv4/tcp.c wouldn't need swap.h any more
since it has already included mm.h.  Similarly, after checking all the
other files, it comes that tcp.c, udp.c meter.c ,...  follow the same
rule, so these files can have swap.h removed too.

Moreover, after preprocessing all the files that use
nr_free_buffer_pages, it turns out that those files have already
included mm.h.Thus, we can move nr_free_buffer_pages from swap.h to mm.h
safely.  This change will not affect the compilation of other files.

Link: https://lkml.kernel.org/r/20210912133640.1624-1-liumh1@shanghaitech.edu.cn
Signed-off-by: Mianhan Liu <liumh1@shanghaitech.edu.cn>
Cc: Jakub Kicinski <kuba@kernel.org>
CC: Ulf Hansson <ulf.hansson@linaro.org>
Cc: "David S . Miller" <davem@davemloft.net>
Cc: Simon Horman <horms@verge.net.au>
Cc: Pravin B Shelar <pshelar@ovn.org>
Cc: Vlad Yasevich <vyasevich@gmail.com>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06 13:30:43 -07:00
Jakub Kicinski
f444fea789 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
drivers/ptp/Kconfig:
  55c8fca1da ("ptp_pch: Restore dependency on PCI")
  e5f3155267 ("ethernet: fix PTP_1588_CLOCK dependencies")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-19 18:09:18 -07:00
kaixi.fan
01634047bf ovs: clear skb->tstamp in forwarding path
fq qdisc requires tstamp to be cleared in the forwarding path. Now ovs
doesn't clear skb->tstamp. We encountered a problem with linux
version 5.4.56 and ovs version 2.14.1, and packets failed to
dequeue from qdisc when fq qdisc was attached to ovs port.

Fixes: fb420d5d91 ("tcp/fq: move back to CLOCK_MONOTONIC")
Signed-off-by: kaixi.fan <fankaixi.li@bytedance.com>
Signed-off-by: xiexiaohui <xiexiaohui.xxh@bytedance.com>
Reviewed-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-18 11:31:13 +01:00
Jakub Kicinski
f4083a752a Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Conflicts:

drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.h
  9e26680733 ("bnxt_en: Update firmware call to retrieve TX PTP timestamp")
  9e518f2580 ("bnxt_en: 1PPS functions to configure TSIO pins")
  099fdeda65 ("bnxt_en: Event handler for PPS events")

kernel/bpf/helpers.c
include/linux/bpf-cgroup.h
  a2baf4e8bb ("bpf: Fix potentially incorrect results with bpf_get_local_storage()")
  c7603cfa04 ("bpf: Add ambient BPF runtime context stored in current")

drivers/net/ethernet/mellanox/mlx5/core/pci_irq.c
  5957cc557d ("net/mlx5: Set all field of mlx5_irq before inserting it to the xarray")
  2d0b41a376 ("net/mlx5: Refcount mlx5_irq with integer")

MAINTAINERS
  7b637cd52f ("MAINTAINERS: fix Microchip CAN BUS Analyzer Tool entry typo")
  7d901a1e87 ("net: phy: add Maxlinear GPY115/21x/24x driver")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-13 06:41:22 -07:00
Randy Dunlap
d6e712aa7e net: openvswitch: fix kernel-doc warnings in flow.c
Repair kernel-doc notation in a few places to make it conform to
the expected format.

Fixes the following kernel-doc warnings:

flow.c:296: warning: This comment starts with '/**', but isn't a kernel-doc comment. Refer Documentation/doc-guide/kernel-doc.rst
 * Parse vlan tag from vlan header.
flow.c:296: warning: missing initial short description on line:
 * Parse vlan tag from vlan header.
flow.c:537: warning: No description found for return value of 'key_extract_l3l4'
flow.c:769: warning: No description found for return value of 'key_extract'

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Pravin B Shelar <pshelar@ovn.org>
Cc: dev@openvswitch.org
Link: https://lore.kernel.org/r/20210808190834.23362-1-rdunlap@infradead.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-09 15:37:35 -07:00
Mark Gray
076999e460 openvswitch: fix sparse warning incorrect type
fix incorrect type in argument 1 (different address spaces)

../net/openvswitch/datapath.c:169:17: warning: incorrect type in argument 1 (different address spaces)
../net/openvswitch/datapath.c:169:17:    expected void const *
../net/openvswitch/datapath.c:169:17:    got struct dp_nlsk_pids [noderef] __rcu *upcall_portids

Found at: https://patchwork.kernel.org/project/netdevbpf/patch/20210630095350.817785-1-mark.d.gray@redhat.com/#24285159

Signed-off-by: Mark Gray <mark.d.gray@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-27 11:48:43 +01:00
Mark Gray
784dcfa56e openvswitch: fix alignment issues
Signed-off-by: Mark Gray <mark.d.gray@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-27 11:48:42 +01:00
Mark Gray
b83d23a2a3 openvswitch: Introduce per-cpu upcall dispatch
The Open vSwitch kernel module uses the upcall mechanism to send
packets from kernel space to user space when it misses in the kernel
space flow table. The upcall sends packets via a Netlink socket.
Currently, a Netlink socket is created for every vport. In this way,
there is a 1:1 mapping between a vport and a Netlink socket.
When a packet is received by a vport, if it needs to be sent to
user space, it is sent via the corresponding Netlink socket.

This mechanism, with various iterations of the corresponding user
space code, has seen some limitations and issues:

* On systems with a large number of vports, there is a correspondingly
large number of Netlink sockets which can limit scaling.
(https://bugzilla.redhat.com/show_bug.cgi?id=1526306)
* Packet reordering on upcalls.
(https://bugzilla.redhat.com/show_bug.cgi?id=1844576)
* A thundering herd issue.
(https://bugzilla.redhat.com/show_bug.cgi?id=1834444)

This patch introduces an alternative, feature-negotiated, upcall
mode using a per-cpu dispatch rather than a per-vport dispatch.

In this mode, the Netlink socket to be used for the upcall is
selected based on the CPU of the thread that is executing the upcall.
In this way, it resolves the issues above as:

a) The number of Netlink sockets scales with the number of CPUs
rather than the number of vports.
b) Ordering per-flow is maintained as packets are distributed to
CPUs based on mechanisms such as RSS and flows are distributed
to a single user space thread.
c) Packets from a flow can only wake up one user space thread.

The corresponding user space code can be found at:
https://mail.openvswitch.org/pipermail/ovs-dev/2021-July/385139.html

Bugzilla: https://bugzilla.redhat.com/1844576
Signed-off-by: Mark Gray <mark.d.gray@redhat.com>
Acked-by: Flavio Leitner <fbl@sysclose.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-16 11:06:33 -07:00
Baowen Zheng
b18114476a openvswitch: Optimize operation for key comparison
In the current implement when comparing two flow keys, we will return
result after comparing the whole key from start to end.

In our optimization, we will return result in the first none-zero
comparison, then we will improve the flow table looking up efficiency.

Signed-off-by: Baowen Zheng <baowen.zheng@corigine.com>
Signed-off-by: Louis Peens <louis.peens@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-01 11:13:10 -07:00
Aaron Conole
c4ab7b56be openvswitch: add trace points
This makes openvswitch module use the event tracing framework
to log the upcall interface and action execution pipeline.  When
using openvswitch as the packet forwarding engine, some types of
debugging are made possible simply by using the ovs-vswitchd's
ofproto/trace command.  However, such a command has some
limitations:

  1. When trying to trace packets that go through the CT action,
     the state of the packet can't be determined, and probably
     would be potentially wrong.

  2. Deducing problem packets can sometimes be difficult as well
     even if many of the flows are known

  3. It's possible to use the openvswitch module even without
     the ovs-vswitchd (although, not common use).

Introduce the event tracing points here to make it possible for
working through these problems in kernel space.  The style is
copied from the mac80211 driver-trace / trace code for
consistency - this creates some checkpatch splats, but the
official 'guide' for adding tracepoints, as well as the existing
examples all add the same splats so it seems acceptable.

Signed-off-by: Aaron Conole <aconole@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 10:47:32 -07:00
Jakub Kicinski
5ada57a9a6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
cdc-wdm: s/kill_urbs/poison_urbs/ to fix build

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-05-27 09:55:10 -07:00
Tao Liu
e4df1b0c24 openvswitch: meter: fix race when getting now_ms.
We have observed meters working unexpected if traffic is 3+Gbit/s
with multiple connections.

now_ms is not pretected by meter->lock, we may get a negative
long_delta_ms when another cpu updated meter->used, then:
    delta_ms = (u32)long_delta_ms;
which will be a large value.

    band->bucket += delta_ms * band->rate;
then we get a wrong band->bucket.

OpenVswitch userspace datapath has fixed the same issue[1] some
time ago, and we port the implementation to kernel datapath.

[1] https://patchwork.ozlabs.org/project/openvswitch/patch/20191025114436.9746-1-i.maximets@ovn.org/

Fixes: 96fbc13d7e ("openvswitch: Add meter infrastructure")
Signed-off-by: Tao Liu <thomas.liu@ucloud.cn>
Suggested-by: Ilya Maximets <i.maximets@ovn.org>
Reviewed-by: Ilya Maximets <i.maximets@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-13 15:54:59 -07:00
Yejune Deng
d2792e91de net: openvswitch: Remove unnecessary skb_nfct()
There is no need add 'if (skb_nfct(skb))' assignment, the
nf_conntrack_put() would check it.

Signed-off-by: Yejune Deng <yejunedeng@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-10 14:18:19 -07:00
Davide Caratti
7c0ea5930c openvswitch: fix stack OOB read while fragmenting IPv4 packets
running openvswitch on kernels built with KASAN, it's possible to see the
following splat while testing fragmentation of IPv4 packets:

 BUG: KASAN: stack-out-of-bounds in ip_do_fragment+0x1b03/0x1f60
 Read of size 1 at addr ffff888112fc713c by task handler2/1367

 CPU: 0 PID: 1367 Comm: handler2 Not tainted 5.12.0-rc6+ #418
 Hardware name: Red Hat KVM, BIOS 1.11.1-4.module+el8.1.0+4066+0f1aadab 04/01/2014
 Call Trace:
  dump_stack+0x92/0xc1
  print_address_description.constprop.7+0x1a/0x150
  kasan_report.cold.13+0x7f/0x111
  ip_do_fragment+0x1b03/0x1f60
  ovs_fragment+0x5bf/0x840 [openvswitch]
  do_execute_actions+0x1bd5/0x2400 [openvswitch]
  ovs_execute_actions+0xc8/0x3d0 [openvswitch]
  ovs_packet_cmd_execute+0xa39/0x1150 [openvswitch]
  genl_family_rcv_msg_doit.isra.15+0x227/0x2d0
  genl_rcv_msg+0x287/0x490
  netlink_rcv_skb+0x120/0x380
  genl_rcv+0x24/0x40
  netlink_unicast+0x439/0x630
  netlink_sendmsg+0x719/0xbf0
  sock_sendmsg+0xe2/0x110
  ____sys_sendmsg+0x5ba/0x890
  ___sys_sendmsg+0xe9/0x160
  __sys_sendmsg+0xd3/0x170
  do_syscall_64+0x33/0x40
  entry_SYSCALL_64_after_hwframe+0x44/0xae
 RIP: 0033:0x7f957079db07
 Code: c3 66 90 41 54 41 89 d4 55 48 89 f5 53 89 fb 48 83 ec 10 e8 eb ec ff ff 44 89 e2 48 89 ee 89 df 41 89 c0 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 48 89 44 24 08 e8 24 ed ff ff 48
 RSP: 002b:00007f956ce35a50 EFLAGS: 00000293 ORIG_RAX: 000000000000002e
 RAX: ffffffffffffffda RBX: 0000000000000019 RCX: 00007f957079db07
 RDX: 0000000000000000 RSI: 00007f956ce35ae0 RDI: 0000000000000019
 RBP: 00007f956ce35ae0 R08: 0000000000000000 R09: 00007f9558006730
 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
 R13: 00007f956ce37308 R14: 00007f956ce35f80 R15: 00007f956ce35ae0

 The buggy address belongs to the page:
 page:00000000af2a1d93 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x112fc7
 flags: 0x17ffffc0000000()
 raw: 0017ffffc0000000 0000000000000000 dead000000000122 0000000000000000
 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
 page dumped because: kasan: bad access detected

 addr ffff888112fc713c is located in stack of task handler2/1367 at offset 180 in frame:
  ovs_fragment+0x0/0x840 [openvswitch]

 this frame has 2 objects:
  [32, 144) 'ovs_dst'
  [192, 424) 'ovs_rt'

 Memory state around the buggy address:
  ffff888112fc7000: f3 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  ffff888112fc7080: 00 f1 f1 f1 f1 00 00 00 00 00 00 00 00 00 00 00
 >ffff888112fc7100: 00 00 00 f2 f2 f2 f2 f2 f2 00 00 00 00 00 00 00
                                         ^
  ffff888112fc7180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  ffff888112fc7200: 00 00 00 00 00 00 f2 f2 f2 00 00 00 00 00 00 00

for IPv4 packets, ovs_fragment() uses a temporary struct dst_entry. Then,
in the following call graph:

  ip_do_fragment()
    ip_skb_dst_mtu()
      ip_dst_mtu_maybe_forward()
        ip_mtu_locked()

the pointer to struct dst_entry is used as pointer to struct rtable: this
turns the access to struct members like rt_mtu_locked into an OOB read in
the stack. Fix this changing the temporary variable used for IPv4 packets
in ovs_fragment(), similarly to what is done for IPv6 few lines below.

Fixes: d52e5a7e7c ("ipv4: lock mtu in fnhe when received PMTU < net.ipv4.route.min_pmt")
Cc: <stable@vger.kernel.org>
Acked-by: Eelco Chaudron <echaudro@redhat.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-04-29 15:31:53 -07:00