This patch provides generic DSA code for using VLAN (802.1Q) tags for
the same purpose as a dedicated switch tag for injection/extraction.
It is based on the discussions and interest that has been so far
expressed in https://www.spinics.net/lists/netdev/msg556125.html.

Unlike all other DSA-supported tagging protocols, CONFIG_NET_DSA_TAG_8021Q
does not offer a complete solution for drivers (nor can it). Instead, it
provides generic code that driver can opt into calling:
- dsa_8021q_xmit: Inserts a VLAN header with the specified contents.
  Can be called from another tagging protocol's xmit function.
  Currently the LAN9303 driver is inserting headers that are simply
  802.1Q with custom fields, so this is an opportunity for code reuse.
- dsa_8021q_rcv: Retrieves the TPID and TCI from a VLAN-tagged skb.
  Removing the VLAN header is left as a decision for the caller to make.
- dsa_port_setup_8021q_tagging: For each user port, installs an Rx VID
  and a Tx VID, for proper untagged traffic identification on ingress
  and steering on egress. Also sets up the VLAN trunk on the upstream
  (CPU or DSA) port. Drivers are intentionally left to call this
  function explicitly, depending on the context and hardware support.
  The expected switch behavior and VLAN semantics should not be violated
  under any conditions. That is, after calling
  dsa_port_setup_8021q_tagging, the hardware should still pass all
  ingress traffic, be it tagged or untagged.

For uniformity with the other tagging protocols, a module for the
dsa_8021q_netdev_ops structure is registered, but the typical usage is
to set up another tagging protocol which selects CONFIG_NET_DSA_TAG_8021Q,
and calls the API from tag_8021q.h. Null function definitions are also
provided so that a "depends on" is not forced in the Kconfig.

This tagging protocol only works when switch ports are standalone, or
when they are added to a VLAN-unaware bridge. It will probably remain
this way for the reasons below.

When added to a bridge that has vlan_filtering 1, the bridge core will
install its own VLANs and reset the pvids through switchdev. For the
bridge core, switchdev is a write-only pipe. All VLAN-related state is
kept in the bridge core and nothing is read from DSA/switchdev or from
the driver. So the bridge core will break this port separation because
it will install the vlan_default_pvid into all switchdev ports.

Even if we could teach the bridge driver about switchdev preference of a
certain vlan_default_pvid (task difficult in itself since the current
setting is per-bridge but we would need it per-port), there would still
exist many other challenges.

Firstly, in the DSA rcv callback, a driver would have to perform an
iterative reverse lookup to find the correct switch port. That is
because the port is a bridge slave, so its Rx VID (port PVID) is subject
to user configuration. How would we ensure that the user doesn't reset
the pvid to a different value (which would make an O(1) translation
impossible), or to a non-unique value within this DSA switch tree (which
would make any translation impossible)?

Finally, not all switch ports are equal in DSA, and that makes it
difficult for the bridge to be completely aware of this anyway.
The CPU port needs to transmit tagged packets (VLAN trunk) in order for
the DSA rcv code to be able to decode source information.
But the bridge code has absolutely no idea which switch port is the CPU
port, if nothing else then just because there is no netdevice registered
by DSA for the CPU port.
Also DSA does not currently allow the user to specify that they want the
CPU port to do VLAN trunking anyway. VLANs are added to the CPU port
using the same flags as they were added on the user port.

So the VLANs installed by dsa_port_setup_8021q_tagging per driver
request should remain private from the bridge's and user's perspective,
and should not alter the VLAN semantics observed by the user.

In the current implementation a VLAN range ending at 4095 (VLAN_N_VID)
is reserved for this purpose. Each port receives a unique Rx VLAN and a
unique Tx VLAN. Separate VLANs are needed for Rx and Tx because they
serve different purposes: on Rx the switch must process traffic as
untagged and process it with a port-based VLAN, but with care not to
hinder bridging. On the other hand, the Tx VLAN is where the
reachability restrictions are imposed, since by tagging frames in the
xmit callback we are telling the switch onto which port to steer the
frame.

Some general guidance on how this support might be employed for
real-life hardware (some comments made by Florian Fainelli):

- If the hardware supports VLAN tag stacking, it should somehow back
  up its private VLAN settings when the bridge tries to override them.
  Then the driver could re-apply them as outer tags. Dedicating an outer
  tag per bridge device would allow identical inner tag VID numbers to
  co-exist, yet preserve broadcast domain isolation.

- If the switch cannot handle VLAN tag stacking, it should disable this
  port separation when added as slave to a vlan_filtering bridge, in
  that case having reduced functionality.

- Drivers for old switches that don't support the entire VLAN_N_VID
  range will need to rework the current range selection mechanism.
Signed-off-by: NVladimir Oltean <olteanv@gmail.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NVivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is needed so that the newly introduced tag_8021q may access these
core DSA functions when built as a module.
Reported-by: Nkbuild test robot <lkp@intel.com>
Signed-off-by: NVladimir Oltean <olteanv@gmail.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This allows the driver to perform some manipulations of its own during
setup, using generic switchdev calls. Having the notifiers registered at
setup time is important because otherwise any switchdev transaction
emitted during this time would be ignored (dispatched to an empty call
chain).

One current usage scenario is for the driver to request DSA to set up
802.1Q based switch tagging for its ports.

There is no danger for the driver setup code to start racing now with
switchdev events emitted from the network stack (such as bridge core)
even if the notifier is registered earlier. This is because the network
stack needs a net_device as a vehicle to perform switchdev operations,
and the slave net_devices are registered later than the core driver
setup anyway (ds->ops->setup in dsa_switch_setup vs dsa_port_setup).

Luckily DSA doesn't need a net_device to carry out switchdev callbacks,
and therefore drivers shouldn't assume either that net_devices are
available at the time their switchdev callbacks get invoked.
Signed-off-by: NVladimir Oltean <olteanv@gmail.com>
Reviewed-by: NFlorian Fainelli <f.fainelli@gmail.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>-
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some actions like the police action are stateful and could share state
between devices. This is incompatible with offloading to multiple devices
and drivers might want to test for shared blocks when offloading.
Store a pointer to the tcf_block structure in the tc_cls_common_offload
structure to allow drivers to determine when offloads apply to a shared
block.
Signed-off-by: NPieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Implement the stats_update callback for the police action that
will be used by drivers for hardware offload.
Signed-off-by: NPieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Introduce a new command for matchall classifiers that allows hardware
to update statistics.
Signed-off-by: NPieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add police action to the hardware intermediate representation which
would subsequently allow it to be used by drivers for offload.
Signed-off-by: NPieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move tcf_police_params, tcf_police and tc_police_compat structures to a
header. Making them usable to other code for example drivers that would
offload police actions to hardware.
Signed-off-by: NPieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Cleanup unused functions and variables after porting to the newer
intermediate representation.
Signed-off-by: NPieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Updates dsa hardware switch handling infrastructure to use the newer
intermediate representation for flow actions in matchall offloads.
Signed-off-by: NPieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Extends matchall offload to make use of the hardware intermediate
representation. More specifically, this patch moves the native TC
actions in cls_matchall offload to the newer flow_action
representation. This ultimately allows us to avoid a direct
dependency on native TC actions for matchall.
Signed-off-by: NPieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add sample action to the hardware intermediate representation model which
would subsequently allow it to be used by drivers for offload.
Signed-off-by: NPieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com>
Reviewed-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes, in particular in the
context in which this code is being used.

So, replace code of the following form:

sizeof(struct xt_hashlimit_htable) + sizeof(struct hlist_head) * size

with:

struct_size(hinfo, hash, size)

This code was detected with the help of Coccinelle.
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

This avoids an indirect call per {send,recv}msg syscall in
the common (IPv6 or IPv4 socket) case.
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

So that we avoid another indirect call per RX packet, if
early demux is enabled.
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

So that we avoid another indirect call per RX packet in the common
case.
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This avoids an indirect call per RX IPv6/IPv4 packet.
Note that we don't want to use the indirect calls helper for taps.
Signed-off-by: NPaolo Abeni <pabeni@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This commit makes the kernel not send the next queued HCI command until
a command complete arrives for the last HCI command sent to the
controller. This change avoids a problem with some buggy controllers
(seen on two SKUs of QCA9377) that send an extra command complete event
for the previous command after the kernel had already sent a new HCI
command to the controller.

The problem was reproduced when starting an active scanning procedure,
where an extra command complete event arrives for the LE_SET_RANDOM_ADDR
command. When this happends the kernel ends up not processing the
command complete for the following commmand, LE_SET_SCAN_PARAM, and
ultimately behaving as if a passive scanning procedure was being
performed, when in fact controller is performing an active scanning
procedure. This makes it impossible to discover BLE devices as no device
found events are sent to userspace.

This problem is reproducible on 100% of the attempts on the affected
controllers. The extra command complete event can be seen at timestamp
27.420131 on the btmon logs bellow.

Bluetooth monitor ver 5.50
= Note: Linux version 5.0.0+ (x86_64)                                  0.352340
= Note: Bluetooth subsystem version 2.22                               0.352343
= New Index: 80:C5:F2:8F:87:84 (Primary,USB,hci0)               [hci0] 0.352344
= Open Index: 80:C5:F2:8F:87:84                                 [hci0] 0.352345
= Index Info: 80:C5:F2:8F:87:84 (Qualcomm)                      [hci0] 0.352346
@ MGMT Open: bluetoothd (privileged) version 1.14             {0x0001} 0.352347
@ MGMT Open: btmon (privileged) version 1.14                  {0x0002} 0.352366
@ MGMT Open: btmgmt (privileged) version 1.14                {0x0003} 27.302164
@ MGMT Command: Start Discovery (0x0023) plen 1       {0x0003} [hci0] 27.302310
        Address type: 0x06
          LE Public
          LE Random
< HCI Command: LE Set Random Address (0x08|0x0005) plen 6   #1 [hci0] 27.302496
        Address: 15:60:F2:91:B2:24 (Non-Resolvable)
> HCI Event: Command Complete (0x0e) plen 4                 #2 [hci0] 27.419117
      LE Set Random Address (0x08|0x0005) ncmd 1
        Status: Success (0x00)
< HCI Command: LE Set Scan Parameters (0x08|0x000b) plen 7  #3 [hci0] 27.419244
        Type: Active (0x01)
        Interval: 11.250 msec (0x0012)
        Window: 11.250 msec (0x0012)
        Own address type: Random (0x01)
        Filter policy: Accept all advertisement (0x00)
> HCI Event: Command Complete (0x0e) plen 4                 #4 [hci0] 27.420131
      LE Set Random Address (0x08|0x0005) ncmd 1
        Status: Success (0x00)
< HCI Command: LE Set Scan Enable (0x08|0x000c) plen 2      #5 [hci0] 27.420259
        Scanning: Enabled (0x01)
        Filter duplicates: Enabled (0x01)
> HCI Event: Command Complete (0x0e) plen 4                 #6 [hci0] 27.420969
      LE Set Scan Parameters (0x08|0x000b) ncmd 1
        Status: Success (0x00)
> HCI Event: Command Complete (0x0e) plen 4                 #7 [hci0] 27.421983
      LE Set Scan Enable (0x08|0x000c) ncmd 1
        Status: Success (0x00)
@ MGMT Event: Command Complete (0x0001) plen 4        {0x0003} [hci0] 27.422059
      Start Discovery (0x0023) plen 1
        Status: Success (0x00)
        Address type: 0x06
          LE Public
          LE Random
@ MGMT Event: Discovering (0x0013) plen 2             {0x0003} [hci0] 27.422067
        Address type: 0x06
          LE Public
          LE Random
        Discovery: Enabled (0x01)
@ MGMT Event: Discovering (0x0013) plen 2             {0x0002} [hci0] 27.422067
        Address type: 0x06
          LE Public
          LE Random
        Discovery: Enabled (0x01)
@ MGMT Event: Discovering (0x0013) plen 2             {0x0001} [hci0] 27.422067
        Address type: 0x06
          LE Public
          LE Random
        Discovery: Enabled (0x01)
Signed-off-by: NJoão Paulo Rechi Vita <jprvita@endlessm.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

The code works fine but the problem is that check for negatives is a
no-op:

	if (arg < 0)
		i = 0;

The "i" value isn't used.  We immediately overwrite it with:

	i = array_index_nospec(arg, MAX_LEC_ITF);

The array_index_nospec() macro returns zero if "arg" is out of bounds so
this works, but the dead code is confusing and it doesn't look very
intentional.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The call to nla_nest_start_noflag can return null in the unlikely
event that nla_put returns -EMSGSIZE.  Check for this condition to
avoid a null pointer dereference on pointer nla_reply.

Addresses-Coverity: ("Dereference null return value")
Fixes: 11efd5cb ("openvswitch: Support conntrack zone limit")
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Acked-by: NYi-Hung Wei <yihung.wei@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Similar to the cached routes, make IPv4 exceptions accessible when
using an IPv6 nexthop struct with IPv4 routes. Simplify the exception
functions by passing in fib_nh_common since that is all it needs,
and then cleanup the call sites that have extraneous fib_nh conversions.

As with the cached routes this is a change in location only, from fib_nh
up to fib_nh_common; no functional change intended.
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Reviewed-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that the cached routes are in fib_nh_common, pass it to
rt_cache_route and simplify its callers. For rt_set_nexthop,
the tclassid becomes the last user of fib_nh so move the
container_of under the #ifdef CONFIG_IP_ROUTE_CLASSID.
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Reviewed-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

While the cached routes, nh_pcpu_rth_output and nh_rth_input, are IPv4
specific, a later patch wants to make them accessible for IPv6 nexthops
with IPv4 routes using a fib6_nh. Move the cached routes from fib_nh to
fib_nh_common and update references.

Initialization of the cached entries is moved to fib_nh_common_init,
and free is moved to fib_nh_common_release.

Change in location only, from fib_nh up to fib_nh_common; no functional
change intended.
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Reviewed-by: NIdo Schimmel <idosch@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For all other error cases in queue_userspace_packet() the error is
returned, so it makes sense to do the same for these two error cases.
Reported-by: NDavide Caratti <dcaratti@redhat.com>
Signed-off-by: NEelco Chaudron <echaudro@redhat.com>
Acked-by: NFlavio Leitner <fbl@sysclose.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Unlike do requests, dump genetlink requests now perform strict validation
by default even if the genetlink family does not set policy and maxtype
because it does validation and parsing on its own (e.g. because it wants to
allow different message format for different commands). While the null
policy will be ignored, maxtype (which would be zero) is still checked so
that any attribute will fail validation.

The solution is to only call __nla_validate() from genl_family_rcv_msg()
if family->maxtype is set.

Fixes: ef6243ac ("genetlink: optionally validate strictly/dumps")
Signed-off-by: NMichal Kubecek <mkubecek@suse.cz>
Reviewed-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

TIPC link can temporarily fall into "half-establish" that only one of
the link endpoints is ESTABLISHED and starts to send traffic, PROTOCOL
messages, whereas the other link endpoint is not up (e.g. immediately
when the endpoint receives ACTIVATE_MSG, the network interface goes
down...).

This is a normal situation and will be settled because the link
endpoint will be eventually brought down after the link tolerance time.

However, the situation will become worse when the second link is
established before the first link endpoint goes down,
For example:

   1. Both links <1A-2A>, <1B-2B> down
   2. Link endpoint 2A up, but 1A still down (e.g. due to network
      disturbance, wrong session, etc.)
   3. Link <1B-2B> up
   4. Link endpoint 2A down (e.g. due to link tolerance timeout)
   5. Node B starts failover onto link <1B-2B>

   ==> Node A does never start link failover.

When the "half-failover" situation happens, two consequences have been
observed:

a) Peer link/node gets stuck in FAILINGOVER state;
b) Traffic or user messages that peer node is trying to failover onto
the second link can be partially or completely dropped by this node.

The consequence a) was actually solved by commit c140eb16 ("tipc:
fix failover problem"), but that commit didn't cover the b). It's due
to the fact that the tunnel link endpoint has never been prepared for a
failover, so the 'l->drop_point' (and the other data...) is not set
correctly. When a TUNNEL_MSG from peer node arrives on the link,
depending on the inner message's seqno and the current 'l->drop_point'
value, the message can be dropped (- treated as a duplicate message) or
processed.
At this early stage, the traffic messages from peer are likely to be
NAME_DISTRIBUTORs, this means some name table entries will be missed on
the node forever!

The commit resolves the issue by starting the FAILOVER process on this
node as well. Another benefit from this solution is that we ensure the
link will not be re-established until the failover ends.
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NTuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Make use of the struct_size() helper instead of an open-coded version
in order to avoid any potential type mistakes, in particular in the
context in which this code is being used.

So, replace code of the following form:

sizeof(*s) + s->nkeys*sizeof(struct tc_u32_key)

with:

struct_size(s, keys, s->nkeys)

This code was detected with the help of Coccinelle.
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Although devlink health report does a nice job on reporting TX
timeout and other NIC errors, unfortunately it requires drivers
to support it but currently only mlx5 has implemented it.
Before other drivers could catch up, it is useful to have a
generic tracepoint to monitor this kind of TX timeout. We have
been suffering TX timeout with different drivers, we plan to
start to monitor it with rasdaemon which just needs a new tracepoint.

Sample output:

  ksoftirqd/1-16    [001] ..s2   144.043173: net_dev_xmit_timeout: dev=ens3 driver=e1000 queue=0

Cc: Eran Ben Elisha <eranbe@mellanox.com>
Cc: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Reviewed-by: NEran Ben Elisha <eranbe@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

syzbot was able to crash host by sending UDP packets with a 0 payload.

TCP does not have this issue since we do not aggregate packets without
payload.

Since dev_gro_receive() sets gso_size based on skb_gro_len(skb)
it seems not worth trying to cope with padded packets.

BUG: KASAN: slab-out-of-bounds in skb_gro_receive+0xf5f/0x10e0 net/core/skbuff.c:3826
Read of size 16 at addr ffff88808893fff0 by task syz-executor612/7889

CPU: 0 PID: 7889 Comm: syz-executor612 Not tainted 5.1.0-rc7+ #96
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 __asan_report_load16_noabort+0x14/0x20 mm/kasan/generic_report.c:133
 skb_gro_receive+0xf5f/0x10e0 net/core/skbuff.c:3826
 udp_gro_receive_segment net/ipv4/udp_offload.c:382 [inline]
 call_gro_receive include/linux/netdevice.h:2349 [inline]
 udp_gro_receive+0xb61/0xfd0 net/ipv4/udp_offload.c:414
 udp4_gro_receive+0x763/0xeb0 net/ipv4/udp_offload.c:478
 inet_gro_receive+0xe72/0x1110 net/ipv4/af_inet.c:1510
 dev_gro_receive+0x1cd0/0x23c0 net/core/dev.c:5581
 napi_gro_frags+0x36b/0xd10 net/core/dev.c:5843
 tun_get_user+0x2f24/0x3fb0 drivers/net/tun.c:1981
 tun_chr_write_iter+0xbd/0x156 drivers/net/tun.c:2027
 call_write_iter include/linux/fs.h:1866 [inline]
 do_iter_readv_writev+0x5e1/0x8e0 fs/read_write.c:681
 do_iter_write fs/read_write.c:957 [inline]
 do_iter_write+0x184/0x610 fs/read_write.c:938
 vfs_writev+0x1b3/0x2f0 fs/read_write.c:1002
 do_writev+0x15e/0x370 fs/read_write.c:1037
 __do_sys_writev fs/read_write.c:1110 [inline]
 __se_sys_writev fs/read_write.c:1107 [inline]
 __x64_sys_writev+0x75/0xb0 fs/read_write.c:1107
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x441cc0
Code: 05 48 3d 01 f0 ff ff 0f 83 9d 09 fc ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 83 3d 51 93 29 00 00 75 14 b8 14 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 74 09 fc ff c3 48 83 ec 08 e8 ba 2b 00 00
RSP: 002b:00007ffe8c716118 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007ffe8c716150 RCX: 0000000000441cc0
RDX: 0000000000000001 RSI: 00007ffe8c716170 RDI: 00000000000000f0
RBP: 0000000000000000 R08: 000000000000ffff R09: 0000000000a64668
R10: 0000000020000040 R11: 0000000000000246 R12: 000000000000c2d9
R13: 0000000000402b50 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 5143:
 save_stack+0x45/0xd0 mm/kasan/common.c:75
 set_track mm/kasan/common.c:87 [inline]
 __kasan_kmalloc mm/kasan/common.c:497 [inline]
 __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:470
 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:505
 slab_post_alloc_hook mm/slab.h:437 [inline]
 slab_alloc mm/slab.c:3393 [inline]
 kmem_cache_alloc+0x11a/0x6f0 mm/slab.c:3555
 mm_alloc+0x1d/0xd0 kernel/fork.c:1030
 bprm_mm_init fs/exec.c:363 [inline]
 __do_execve_file.isra.0+0xaa3/0x23f0 fs/exec.c:1791
 do_execveat_common fs/exec.c:1865 [inline]
 do_execve fs/exec.c:1882 [inline]
 __do_sys_execve fs/exec.c:1958 [inline]
 __se_sys_execve fs/exec.c:1953 [inline]
 __x64_sys_execve+0x8f/0xc0 fs/exec.c:1953
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 5351:
 save_stack+0x45/0xd0 mm/kasan/common.c:75
 set_track mm/kasan/common.c:87 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/common.c:459
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:467
 __cache_free mm/slab.c:3499 [inline]
 kmem_cache_free+0x86/0x260 mm/slab.c:3765
 __mmdrop+0x238/0x320 kernel/fork.c:677
 mmdrop include/linux/sched/mm.h:49 [inline]
 finish_task_switch+0x47b/0x780 kernel/sched/core.c:2746
 context_switch kernel/sched/core.c:2880 [inline]
 __schedule+0x81b/0x1cc0 kernel/sched/core.c:3518
 preempt_schedule_irq+0xb5/0x140 kernel/sched/core.c:3745
 retint_kernel+0x1b/0x2d
 arch_local_irq_restore arch/x86/include/asm/paravirt.h:767 [inline]
 kmem_cache_free+0xab/0x260 mm/slab.c:3766
 anon_vma_chain_free mm/rmap.c:134 [inline]
 unlink_anon_vmas+0x2ba/0x870 mm/rmap.c:401
 free_pgtables+0x1af/0x2f0 mm/memory.c:394
 exit_mmap+0x2d1/0x530 mm/mmap.c:3144
 __mmput kernel/fork.c:1046 [inline]
 mmput+0x15f/0x4c0 kernel/fork.c:1067
 exec_mmap fs/exec.c:1046 [inline]
 flush_old_exec+0x8d9/0x1c20 fs/exec.c:1279
 load_elf_binary+0x9bc/0x53f0 fs/binfmt_elf.c:864
 search_binary_handler fs/exec.c:1656 [inline]
 search_binary_handler+0x17f/0x570 fs/exec.c:1634
 exec_binprm fs/exec.c:1698 [inline]
 __do_execve_file.isra.0+0x1394/0x23f0 fs/exec.c:1818
 do_execveat_common fs/exec.c:1865 [inline]
 do_execve fs/exec.c:1882 [inline]
 __do_sys_execve fs/exec.c:1958 [inline]
 __se_sys_execve fs/exec.c:1953 [inline]
 __x64_sys_execve+0x8f/0xc0 fs/exec.c:1953
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff88808893f7c0
 which belongs to the cache mm_struct of size 1496
The buggy address is located 600 bytes to the right of
 1496-byte region [ffff88808893f7c0, ffff88808893fd98)
The buggy address belongs to the page:
page:ffffea0002224f80 count:1 mapcount:0 mapping:ffff88821bc40ac0 index:0xffff88808893f7c0 compound_mapcount: 0
flags: 0x1fffc0000010200(slab|head)
raw: 01fffc0000010200 ffffea00025b4f08 ffffea00027b9d08 ffff88821bc40ac0
raw: ffff88808893f7c0 ffff88808893e440 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88808893fe80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88808893ff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88808893ff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                                             ^
 ffff888088940000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888088940080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

Fixes: e20cf8d3 ("udp: implement GRO for plain UDP sockets.")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Reported-by: Nsyzbot <syzkaller@googlegroups.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is a followup after the fix in
commit 9c69a132 ("route: Avoid crash from dereferencing NULL rt->from")

rt6_do_redirect():
1. NULL checking is needed on rt->from because a parallel
   fib6_info delete could happen that sets rt->from to NULL.
   (e.g. rt6_remove_exception() and fib6_drop_pcpu_from()).

2. fib6_info_hold() is not enough.  Same reason as (1).
   Meaning, holding dst->__refcnt cannot ensure
   rt->from is not NULL or rt->from->fib6_ref is not 0.

   Instead of using fib6_info_hold_safe() which ip6_rt_cache_alloc()
   is already doing, this patch chooses to extend the rcu section
   to keep "from" dereference-able after checking for NULL.

inet6_rtm_getroute():
1. NULL checking is also needed on rt->from for a similar reason.
   Note that inet6_rtm_getroute() is using RTNL_FLAG_DOIT_UNLOCKED.

Fixes: a68886a6 ("net/ipv6: Make from in rt6_info rcu protected")
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Acked-by: NWei Wang <weiwan@google.com>
Reviewed-by: NDavid Ahern <dsahern@gmail.com>
Reviewed-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

While the endiannes is being handled correctly as indicated by the comment
above the offending line - sparse was unhappy with the missing annotation
as be64_to_cpu() expects a __be64 argument. To mitigate this annotation
all involved variables are changed to a consistent __le64 and the
 conversion to uint64_t delayed to the call to rds_cong_map_updated().
Signed-off-by: NNicholas Mc Guire <hofrat@osadl.org>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Previously, during fragmentation after forwarding, skb->skb_iif isn't
preserved, i.e. 'ip_copy_metadata' does not copy skb_iif from given
'from' skb.

As a result, ip_do_fragment's creates fragments with zero skb_iif,
leading to inconsistent behavior.

Assume for example an eBPF program attached at tc egress (post
forwarding) that examines __sk_buff->ingress_ifindex:
 - the correct iif is observed if forwarding path does not involve
   fragmentation/refragmentation
 - a bogus iif is observed if forwarding path involves
   fragmentation/refragmentatiom

Fix, by preserving skb_iif during 'ip_copy_metadata'.
Signed-off-by: NShmulik Ladkani <shmulik.ladkani@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

IEEE 802.1Q-2018 defines the concept of a cycle-time-extension, so the
last entry of a schedule before the start of a new schedule can be
extended, so "too-short" entries can be avoided.
Signed-off-by: NVinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

IEEE 802.1Q-2018 defines that a the cycle-time of a schedule may be
overridden, so the schedule is truncated to a determined "width".
Signed-off-by: NVinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The IEEE 802.1Q-2018 defines two "types" of schedules, the "Oper" (from
operational?) and "Admin" ones. Up until now, 'taprio' only had
support for the "Oper" one, added when the qdisc is created. This adds
support for the "Admin" one, which allows the .change() operation to
be supported.

Just for clarification, some quick (and dirty) definitions, the "Oper"
schedule is the currently (as in this instant) running one, and it's
read-only. The "Admin" one is the one that the system configurator has
installed, it can be changed, and it will be "promoted" to "Oper" when
it's 'base-time' is reached.

The idea behing this patch is that calling something like the below,
(after taprio is already configured with an initial schedule):

$ tc qdisc change taprio dev IFACE parent root 	     \
     	   base-time X 	     	   	       	     \
     	   sched-entry <CMD> <GATES> <INTERVAL>	     \
	   ...

Will cause a new admin schedule to be created and programmed to be
"promoted" to "Oper" at instant X. If an "Admin" schedule already
exists, it will be overwritten with the new parameters.

Up until now, there was some code that was added to ease the support
of changing a single entry of a schedule, but was ultimately unused.
Now, that we have support for "change" with more well thought
semantics, updating a single entry seems to be less useful.

So we remove what is in practice dead code, and return a "not
supported" error if the user tries to use it. If changing a single
entry would make the user's life easier we may ressurrect this idea,
but at this point, removing it simplifies the code.

For now, only the schedule specific bits are allowed to be added for a
new schedule, that means that 'clockid', 'num_tc', 'map' and 'queues'
cannot be modified.

Example:

$ tc qdisc change dev IFACE parent root handle 100 taprio \
      base-time $BASE_TIME \
      sched-entry S 00 500000 \
      sched-entry S 0f 500000 \
      clockid CLOCK_TAI

The only change in the netlink API introduced by this change is the
introduction of an "admin" type in the response to a dump request,
that type allows userspace to separate the "oper" schedule from the
"admin" schedule. If userspace doesn't support the "admin" type, it
will only display the "oper" schedule.
Signed-off-by: NVinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Right now, this isn't a problem, but the next commit allows schedules
to be added during runtime. When a new schedule transitions from the
inactive to the active state ("admin" -> "oper") the previous one can
be freed, if it's freed just after the RCU read lock is released, we
may access an invalid entry.

So, we should take care to protect the dequeue() flow, so all the
places that access the entries are protected by the RCU read lock.
Signed-off-by: NVinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Relocate the congestion window initialization from tcp_init_metrics()
to tcp_init_transfer() to improve code readability.
Signed-off-by: NYuchung Cheng <ycheng@google.com>
Signed-off-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NSoheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use a helper to consolidate two identical code block for passive TFO.
Signed-off-by: NYuchung Cheng <ycheng@google.com>
Signed-off-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NSoheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch makes passive Fast Open reverts the cwnd to default
initial cwnd (10 packets) if the SYNACK timeout is spurious.

Passive Fast Open uses a full socket during handshake so it can
use the existing undo logic to detect spurious retransmission
by recording the first SYNACK timeout in key state variable
retrans_stamp. Upon receiving the ACK of the SYNACK, if the socket
has sent some data before the timeout, the spurious timeout
is detected by tcp_try_undo_recovery() in tcp_process_loss()
in tcp_ack().

But if the socket has not send any data yet, tcp_ack() does not
execute the undo code since no data is acknowledged. The fix is to
check such case explicitly after tcp_ack() during the ACK processing
in SYN_RECV state. In addition this is checked in FIN_WAIT_1 state
in case the server closes the socket before handshake completes.
Signed-off-by: NYuchung Cheng <ycheng@google.com>
Signed-off-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NSoheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

TCP sender would use congestion window of 1 packet on the second SYN
and SYNACK timeout except passive TCP Fast Open. This makes passive
TFO too aggressive and unfair during congestion at handshake. This
patch fixes this issue so TCP (fast open or not, passive or active)
always conforms to the RFC6298.

Note that tcp_enter_loss() is called only once during recurring
timeouts.  This is because during handshake, high_seq and snd_una
are the same so tcp_enter_loss() would incorrect set the undo state
variables multiple times.
Signed-off-by: NYuchung Cheng <ycheng@google.com>
Signed-off-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>