Fix trivial spelling mistake "greater then" -> "greater than".
Signed-off-by: NGal Pressman <galp@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

netif_set_real_num_tx_queues() can be called when netdev is up.
That usually happens when user requests change of number of
channels/rings with ethtool -L.  The procedure for changing
the number of queues involves resetting the qdiscs and setting
dev->num_tx_queues to the new value.  When the new value is
lower than the old one, extra care has to be taken to ensure
ordering of accesses to the number of queues vs qdisc reset.

Currently the queues are reset before new dev->num_tx_queues
is assigned, leaving a window of time where packets can be
enqueued onto the queues going down, leading to a likely
crash in the drivers, since most drivers don't check if TX
skbs are assigned to an active queue.

Fixes: e6484930 ("net: allocate tx queues in register_netdevice")
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These pernet operations consist of exit() and exit_batch() methods.

default_device_exit() moves not-local and virtual devices to init_net.
There is nothing exciting, because this may happen in any time
on a working system, and rtnl_lock() and synchronize_net() protect
us from all cases of external dereference.

The same for default_device_exit_batch(). Similar unregisteration
may happen in any time on a system. Here several lists (like todo_list),
which are accessed under rtnl_lock(). After rtnl_unlock() and
netdev_run_todo() all the devices are flushed.
Signed-off-by: NKirill Tkhai <ktkhai@virtuozzo.com>
Acked-by: NAndrei Vagin <avagin@virtuozzo.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There are:
1)dev_proc_ops and dev_mc_net_ops, which create and destroy
pernet proc file and not interesting for another net namespaces;
2)netdev_net_ops, which creates pernet hashes, which are not
touched by another pernet_operations.

So, make them async.
Signed-off-by: NKirill Tkhai <ktkhai@virtuozzo.com>
Acked-by: NAndrei Vagin <avagin@virtuozzo.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Introduce a new qdisc ops ->change_tx_queue_len() so that
each qdisc could decide how to implement this if it wants.
Previously we simply read dev->tx_queue_len, after pfifo_fast
switches to skb array, we need this API to resize the skb array
when we change dev->tx_queue_len.

To avoid handling race conditions with TX BH, we need to
deactivate all TX queues before change the value and bring them
back after we are done, this also makes implementation easier.

Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch promotes the local change_tx_queue_len() to a core
helper function, dev_change_tx_queue_len(), so that rtnetlink
and net-sysfs could share the code. This also prepares for the
following patch.

Note, the -EFAULT in the original code doesn't make sense,
we should propagate the errno from notifiers.

Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The goal is to let the user follow an interface that moves to another
netns.

CC: Jiri Benc <jbenc@redhat.com>
CC: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: NJiri Benc <jbenc@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The user should be able to follow any interface that moves to another
netns.  There is no reason to hide physical interfaces.

CC: Jiri Benc <jbenc@redhat.com>
CC: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: NJiri Benc <jbenc@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fixes the following warnings:
./net/core/dev.c:6438: warning: No description found for parameter 'extack'
./net/core/dev.c:6461: warning: No description found for parameter 'extack'

Fixes: 42ab19ee ("net: Add extack to upper device linking")
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove the @dev comment, since we do not have a net_device argument, fixes the
following kernel doc warning: /net/core/dev.c:1707: warning: Excess function
parameter 'dev' description in 'call_netdevice_notifiers_info'
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Without proper validation of DODGY packets, we might very well
feed qdisc_pkt_len_init() with invalid GSO packets.

tcp_hdrlen() might access out-of-bound data, so let's use
skb_header_pointer() and proper checks.

Whole story is described in commit d0c081b4 ("flow_dissector:
properly cap thoff field")

We have the goal of validating DODGY packets earlier in the stack,
so we might very well revert this fix in the future.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Jason Wang <jasowang@redhat.com>
Reported-by: syzbot+9da69ebac7dddd804552@syzkaller.appspotmail.com
Acked-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

With the recent fix to ixgbe we can cap the number of queues always
regardless of if accel_priv is being used or not since the actual number of
queues are being reported via real_num_tx_queues.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Looks like commit e817f856 ("xdp: generic XDP handling of
xdp_rxq_info") replaced kvfree(dev->_rx) in free_netdev() with
a call to netif_free_rx_queues() which doesn't actually free
the rings?

While at it remove the unnecessary temporary variable.

Fixes: e817f856 ("xdp: generic XDP handling of xdp_rxq_info")
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Acked-by: NJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

kvzalloc'ed memory should be kvfree'd.

Fixes: e817f856 ("xdp: generic XDP handling of xdp_rxq_info")
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Acked-by: NJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Hook points for xdp_rxq_info:
 * reg  : netif_alloc_rx_queues
 * unreg: netif_free_rx_queues

The net_device have some members (num_rx_queues + real_num_rx_queues)
and data-area (dev->_rx with struct netdev_rx_queue's) that were
primarily used for exporting information about RPS (CONFIG_RPS) queues
to sysfs (CONFIG_SYSFS).

For generic XDP extend struct netdev_rx_queue with the xdp_rxq_info,
and remove some of the CONFIG_SYSFS ifdefs.
Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

This reverts commit 87c320e5.

Changing the error return code in some situations turns out to
be harmful in practice.  In particular Michael Ellerman reports
that DHCP fails on his powerpc machines, and this revert gets
things working again.

Johannes Berg agrees that this revert is the best course of
action for now.

Fixes: 029b6d14 ("Revert "net: core: maybe return -EEXIST in __dev_alloc_name"")
Reported-by: NMichael Ellerman <mpe@ellerman.id.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch implements asynchronous crypto callbacks
and a backlog handler that can be used when IPsec
is done at layer 2 in the TX path. It also extends
the skb validate functions so that we can update
the driver transmit return codes based on async
crypto operation or to indicate that we queued the
packet in a backlog queue.

Joint work with: Aviv Heller <avivh@mellanox.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

We change the ESP GSO handlers to only segment the packets.
The ESP handling and encryption is defered to validate_xmit_xfrm()
where this is done for non GRO packets too. This makes the code
more robust and prepares for asynchronous crypto handling.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Hardware should not aggregate any packets when generic XDP is installed.

Cc: Ariel Elior <Ariel.Elior@cavium.com>
Cc: everest-linux-l2@cavium.com
Signed-off-by: NMichael Chan <michael.chan@broadcom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Introduce NETIF_F_GRO_HW feature flag for NICs that support hardware
GRO.  With this flag, we can now independently turn on or off hardware
GRO when GRO is on.  Previously, drivers were using NETIF_F_GRO to
control hardware GRO and so it cannot be independently turned on or
off without affecting GRO.

Hardware GRO (just like GRO) guarantees that packets can be re-segmented
by TSO/GSO to reconstruct the original packet stream.  Logically,
GRO_HW should depend on GRO since it a subset, but we will let
individual drivers enforce this dependency as they see fit.

Since NETIF_F_GRO is not propagated between upper and lower devices,
NETIF_F_GRO_HW should follow suit since it is a subset of GRO.  In other
words, a lower device can independent have GRO/GRO_HW enabled or disabled
and no feature propagation is required.  This will preserve the current
GRO behavior.  This can be changed later if we decide to propagate GRO/
GRO_HW/RXCSUM from upper to lower devices.

Cc: Ariel Elior <Ariel.Elior@cavium.com>
Cc: everest-linux-l2@cavium.com
Signed-off-by: NMichael Chan <michael.chan@broadcom.com>
Acked-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In netif_receive_generic_xdp(), it is necessary to linearize all
nonlinear skb. However, in current implementation, skb with
troom <= 0 are not linearized. This patch fixes this by calling
skb_linearize() for all nonlinear skb.

Fixes: de8f3a83 ("bpf: add meta pointer for direct access")
Signed-off-by: NSong Liu <songliubraving@fb.com>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

skb_warn_bad_offload warns when packets enter the GSO stack that
require skb_checksum_help or vice versa. Do not warn on arbitrary
bad packets. Packet sockets can craft many. Syzkaller was able to
demonstrate another one with eth_type games.

In particular, suppress the warning when segmentation returns an
error, which is for reasons other than checksum offload.

See also commit 36c92474 ("net: WARN if skb_checksum_help() is
called on skb requiring segmentation") for context on this warning.
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds a flag for queueing disciplines to indicate the stack
does not need to use the qdisc lock to protect operations. This can
be used to build lockless scheduling algorithms and improving
performance.

The flag is checked in the tx path and the qdisc lock is only taken
if it is not set. For now use a conditional if statement. Later we
could be more aggressive if it proves worthwhile and use a static key
or wrap this in a likely().

Also the lockless case drops the TCQ_F_CAN_BYPASS logic. The reason
for this is synchronizing a qlen counter across threads proves to
cost more than doing the enqueue/dequeue operations when tested with
pktgen.
Signed-off-by: NJohn Fastabend <john.fastabend@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently __qdisc_run calls qdisc_run_end() but does not call
qdisc_run_begin(). This makes it hard to track pairs of
qdisc_run_{begin,end} across function calls.

To simplify reading these code paths this patch moves begin/end calls
into qdisc_run().
Signed-off-by: NJohn Fastabend <john.fastabend@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit d6f295e9; some userspace (in the case
we noticed it's wpa_supplicant), is relying on the current
error code to determine that a fixed name interface already
exists.
Reported-by: NJouni Malinen <j@w1.fi>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since day one of XDP drivers had to remember to free the program
on the remove path.  This leads to code duplication and is error
prone.  Make the stack query the installed programs on unregister
and if something is installed, remove the program.  Freeing of
program attached to XDP generic is moved from free_netdev() as well.

Because the remove will now be called before notifiers are
invoked, BPF offload state of the program will not get destroyed
before uninstall.
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Reviewed-by: NQuentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

The output parameters will get unwieldy if we want to add more
information about the program.  Simply pass the entire
struct netdev_bpf in.
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Reviewed-by: NQuentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

Tuntap and similar devices can inject GSO packets. Accept type
VIRTIO_NET_HDR_GSO_UDP, even though not generating UFO natively.

Processes are expected to use feature negotiation such as TUNSETOFFLOAD
to detect supported offload types and refrain from injecting other
packets. This process breaks down with live migration: guest kernels
do not renegotiate flags, so destination hosts need to expose all
features that the source host does.

Partially revert the UFO removal from 182e0b6b~1..d9d30adf.
This patch introduces nearly(*) no new code to simplify verification.
It brings back verbatim tuntap UFO negotiation, VIRTIO_NET_HDR_GSO_UDP
insertion and software UFO segmentation.

It does not reinstate protocol stack support, hardware offload
(NETIF_F_UFO), SKB_GSO_UDP tunneling in SKB_GSO_SOFTWARE or reception
of VIRTIO_NET_HDR_GSO_UDP packets in tuntap.

To support SKB_GSO_UDP reappearing in the stack, also reinstate
logic in act_csum and openvswitch. Achieve equivalence with v4.13 HEAD
by squashing in commit 93991221 ("net: skb_needs_check() removes
CHECKSUM_UNNECESSARY check for tx.") and reverting commit 8d63bee6
("net: avoid skb_warn_bad_offload false positives on UFO").

(*) To avoid having to bring back skb_shinfo(skb)->ip6_frag_id,
ipv6_proxy_select_ident is changed to return a __be32 and this is
assigned directly to the frag_hdr. Also, SKB_GSO_UDP is inserted
at the end of the enum to minimize code churn.

Tested
  Booted a v4.13 guest kernel with QEMU. On a host kernel before this
  patch `ethtool -k eth0` shows UFO disabled. After the patch, it is
  enabled, same as on a v4.13 host kernel.

  A UFO packet sent from the guest appears on the tap device:
    host:
      nc -l -p -u 8000 &
      tcpdump -n -i tap0

    guest:
      dd if=/dev/zero of=payload.txt bs=1 count=2000
      nc -u 192.16.1.1 8000 < payload.txt

  Direct tap to tap transmission of VIRTIO_NET_HDR_GSO_UDP succeeds,
  packets arriving fragmented:

    ./with_tap_pair.sh ./tap_send_ufo tap0 tap1
    (from https://github.com/wdebruij/kerneltools/tree/master/tests)

Changes
  v1 -> v2
    - simplified set_offload change (review comment)
    - documented test procedure

Link: http://lkml.kernel.org/r/<CAF=yD-LuUeDuL9YWPJD9ykOZ0QCjNeznPDr6whqZ9NGMNF12Mw@mail.gmail.com>
Fixes: fb652fdf ("macvlan/macvtap: Remove NETIF_F_UFO advertisement.")
Reported-by: NMichal Kubecek <mkubecek@suse.cz>
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Acked-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently device-bound programs are not able to run on the host
to save resources (host JIT is not invoked).  Don't allow XDP
programs to be attached without the HW_MODE flag.  In theory
if program is already translated for device offload the driver
should choose to offload it instead of loading it in the driver.
However, offloading translated program may still fail resulting
in device-bound program being run on the host.

Prevent this by refusing to attach device bound programs if
XDP_FLAGS_HW_MODE is not set.
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NQuentin Monnet <quentin.monnet@netronome.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

With TC shared block changes we can't depend on correct netdev
pointer being available in cls_bpf.  Move the device validation
to the driver.  Core will only make sure that offloaded programs
are always attached in the driver (or in HW by the driver).  We
trust that drivers which implement offload callbacks will perform
necessary checks.

Moving the checks to the driver is generally a useful thing,
in practice the check should be against a switchdev instance,
not a netdev, given that most ASICs will probably allow using
the same program on many ports.
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NQuentin Monnet <quentin.monnet@netronome.com>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>

If name contains a %, it's easy to see that this patch doesn't change
anything (other than eliminate the duplicate dev_valid_name
call). Otherwise, we'll now just spend a little time in snprintf()
copying name to the stack buffer allocated in dev_alloc_name_ns, and do
the __dev_get_by_name using that buffer rather than name.
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If we're given format string with no %d, -EEXIST is a saner error code.
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We currently only exclude non-sysfs-friendly names via
dev_get_valid_name; there doesn't seem to be a reason to allow such
names when we're called via dev_alloc_name.

This does duplicate the dev_valid_name check in the dev_get_valid_name()
case; we'll fix that shortly.
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The only caller passes a stack buffer as buf, so it won't equal the
passed-in name. Moreover, we're already using buf as a scratch buffer
inside the if (p) {} block, so if buf and name were the same, that
snprintf() call would be overwriting its own format string.
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

dev_alloc_name contained a BUG_ON(), which I moved to dev_alloc_name_ns;
the only other caller of that already has the same BUG_ON.
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

No functional change.
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

__dev_alloc_name is called from the public (and exported)
dev_alloc_name(), so we don't have a guarantee that strlen(name) is at
most IFNAMSIZ. If somebody manages to get __dev_alloc_name called with a
% char beyond the 31st character, we'd be making a snprintf() call that
will very easily crash the kernel (using an appropriate %p extension,
we'll likely dereference some completely bogus pointer).

In the normal case where strlen() is sane, we don't even save anything
by limiting to IFNAMSIZ, so just use strchr().
Signed-off-by: NRasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Be sure that dev_base_head list initialized in net_init hook was return
to initial state
Signed-off-by: NVasily Averin <vvs@virtuozzo.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pass the netdev pointer to bpf_prog_get_type().  This way
BPF code can decide whether the device matches what the
code was loaded/translated for.
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: NSimon Horman <simon.horman@netronome.com>
Reviewed-by: NQuentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>