linux.git/net/openvswitch, branch v5.14

ovs: clear skb->tstamp in forwarding path

2021-08-18T10:31:13+00:00

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: fb420d5d91c1 ("tcp/fq: move back to CLOCK_MONOTONIC")
Signed-off-by: kaixi.fan 
Signed-off-by: xiexiaohui 
Reviewed-by: Cong Wang 
Signed-off-by: David S. Miller

net: openvswitch: fix kernel-doc warnings in flow.c

2021-08-09T22:37:35+00:00

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 
Cc: Pravin B Shelar 
Cc: dev@openvswitch.org
Link: https://lore.kernel.org/r/20210808190834.23362-1-rdunlap@infradead.org
Signed-off-by: Jakub Kicinski

openvswitch: Optimize operation for key comparison

2021-07-01T18:13:10+00:00

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 
Signed-off-by: Louis Peens 
Signed-off-by: Simon Horman 
Signed-off-by: David S. Miller

openvswitch: add trace points

2021-06-22T17:47:32+00:00

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 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2021-05-27T16:55:10+00:00

cdc-wdm: s/kill_urbs/poison_urbs/ to fix build

Signed-off-by: Jakub Kicinski

openvswitch: meter: fix race when getting now_ms.

2021-05-13T22:54:59+00:00

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: 96fbc13d7e77 ("openvswitch: Add meter infrastructure")
Signed-off-by: Tao Liu 
Suggested-by: Ilya Maximets 
Reviewed-by: Ilya Maximets 
Signed-off-by: David S. Miller

net: openvswitch: Remove unnecessary skb_nfct()

2021-05-10T21:18:19+00:00

There is no need add 'if (skb_nfct(skb))' assignment, the
nf_conntrack_put() would check it.

Signed-off-by: Yejune Deng 
Signed-off-by: David S. Miller

openvswitch: fix stack OOB read while fragmenting IPv4 packets

2021-04-29T22:31:53+00:00

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: d52e5a7e7ca4 ("ipv4: lock mtu in fnhe when received PMTU < net.ipv4.route.min_pmt")
Cc: 
Acked-by: Eelco Chaudron 
Signed-off-by: Davide Caratti 
Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2021-04-26T19:00:00+00:00

openvswitch: meter: remove rate from the bucket size calculation

2021-04-23T20:08:47+00:00

Implementation of meters supposed to be a classic token bucket with 2
typical parameters: rate and burst size.

Burst size in this schema is the maximum number of bytes/packets that
could pass without being rate limited.

Recent changes to userspace datapath made meter implementation to be
in line with the kernel one, and this uncovered several issues.

The main problem is that maximum bucket size for unknown reason
accounts not only burst size, but also the numerical value of rate.
This creates a lot of confusion around behavior of meters.

For example, if rate is configured as 1000 pps and burst size set to 1,
this should mean that meter will tolerate bursts of 1 packet at most,
i.e. not a single packet above the rate should pass the meter.
However, current implementation calculates maximum bucket size as
(rate + burst size), so the effective bucket size will be 1001.  This
means that first 1000 packets will not be rate limited and average
rate might be twice as high as the configured rate.  This also makes
it practically impossible to configure meter that will have burst size
lower than the rate, which might be a desirable configuration if the
rate is high.

Inability to configure low values of a burst size and overall inability
for a user to predict what will be a maximum and average rate from the
configured parameters of a meter without looking at the OVS and kernel
code might be also classified as a security issue, because drop meters
are frequently used as a way of protection from DoS attacks.

This change removes rate from the calculation of a bucket size, making
it in line with the classic token bucket algorithm and essentially
making the rate and burst tolerance being predictable from a users'
perspective.

Same change proposed for the userspace implementation.

Fixes: 96fbc13d7e77 ("openvswitch: Add meter infrastructure")
Signed-off-by: Ilya Maximets 
Signed-off-by: David S. Miller