With eBPF getting more extended and exposure to user space is on it's way,
hardening the memory range the interpreter uses to steer its command flow
seems appropriate.  This patch moves the to be interpreted bytecode to
read-only pages.

In case we execute a corrupted BPF interpreter image for some reason e.g.
caused by an attacker which got past a verifier stage, it would not only
provide arbitrary read/write memory access but arbitrary function calls
as well. After setting up the BPF interpreter image, its contents do not
change until destruction time, thus we can setup the image on immutable
made pages in order to mitigate modifications to that code. The idea
is derived from commit 314beb9b ("x86: bpf_jit_comp: secure bpf jit
against spraying attacks").

This is possible because bpf_prog is not part of sk_filter anymore.
After setup bpf_prog cannot be altered during its life-time. This prevents
any modifications to the entire bpf_prog structure (incl. function/JIT
image pointer).

Every eBPF program (including classic BPF that are migrated) have to call
bpf_prog_select_runtime() to select either interpreter or a JIT image
as a last setup step, and they all are being freed via bpf_prog_free(),
including non-JIT. Therefore, we can easily integrate this into the
eBPF life-time, plus since we directly allocate a bpf_prog, we have no
performance penalty.

Tested with seccomp and test_bpf testsuite in JIT/non-JIT mode and manual
inspection of kernel_page_tables.  Brad Spengler proposed the same idea
via Twitter during development of this patch.

Joint work with Hannes Frederic Sowa.
Suggested-by: NBrad Spengler <spender@grsecurity.net>
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Kees Cook <keescook@chromium.org>
Acked-by: NAlexei Starovoitov <ast@plumgrid.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As in IPv6 people might increase the igmp query robustness variable to
make sure unsolicited state change reports aren't lost on the network. Add
and document this new knob to igmp code.

RFCs allow tuning this parameter back to first IGMP RFC, so we also use
this setting for all counters, including source specific multicast.

Also take over sysctl value when upping the interface and don't reuse
the last one seen on the interface.

Cc: Flavio Leitner <fbl@redhat.com>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: NFlavio Leitner <fbl@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds a new sysctl_mld_qrv knob to configure the mldv1/v2 query
robustness variable. It specifies how many retransmit of unsolicited mld
retransmit should happen. Admins might want to tune this on lossy links.

Also reset mld state on interface down/up, so we pick up new sysctl
settings during interface up event.

IPv6 certification requests this knob to be available.

I didn't make this knob netns specific, as it is mostly a setting in a
physical environment and should be per host.

Cc: Flavio Leitner <fbl@redhat.com>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: NFlavio Leitner <fbl@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In commit 50cbe9ab ("net: Validate xmit SKBs right when we
pull them out of the qdisc") the validation code was moved out of
dev_hard_start_xmit and into dequeue_skb.

However this overlooked the fact that we do not always enqueue
the skb onto a qdisc. First situation is if qdisc have flag
TCQ_F_CAN_BYPASS and qdisc is empty.  Second situation is if
there is no qdisc on the device, which is a common case for
software devices.

Originally spotted and inital patch by Alexander Duyck.
As a result Alex was seeing issues trying to connect to a
vhost_net interface after commit 50cbe9ab was applied.

Added a call to validate_xmit_skb() in __dev_xmit_skb(), in the
code path for qdiscs with TCQ_F_CAN_BYPASS flag, and in
__dev_queue_xmit() when no qdisc.

Also handle the error situation where dev_hard_start_xmit() could
return a skb list, and does not return dev_xmit_complete(rc) and
falls through to the kfree_skb(), in that situation it should
call kfree_skb_list().

Fixes:  50cbe9ab ("net: Validate xmit SKBs right when we pull them out of the qdisc")
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

More minor fixes to merge commit 53fda7f7 (Merge branch 'xmit_list')
that allows us to work with a list of SKBs.

Fixing exit cases in qdisc_reset() and qdisc_destroy(), where a
leftover requeued SKB (qdisc->gso_skb) can have the potential of
being a skb list, thus use kfree_skb_list().

This is a followup to commit 10770bc2 ("qdisc: adjustments for
API allowing skb list xmits").
Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Minor adjustments for merge commit 53fda7f7 (Merge branch 'xmit_list')
that allows us to work with a list of SKBs.

Update code doc to function sch_direct_xmit().

In handle_dev_cpu_collision() use kfree_skb_list() in error handling.
Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Depending on which parameters were updated, the changes were not propagated via
the notifier chain and netlink.

The new flag has been set only when the change did not cause a call to the
notifier chain and/or to the netlink notification functions.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There is no functional changes with this commit, it only prepares the next one.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The only effect of this patch is to print a warning if IFLA_LINKMODE is updated
and a following change fails.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The only effect of this patch is to print a warning if IFLA_TXQLEN is updated
and a following change fails.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

sk->sk_error_queue is dequeued in four locations. All share the
exact same logic. Deduplicate.

Also collapse the two critical sections for dequeue (at the top of
the recv handler) and signal (at the bottom).

This moves signal generation for the next packet forward, which should
be harmless.

It also changes the behavior if the recv handler exits early with an
error. Previously, a signal for follow-up packets on the errqueue
would then not be scheduled. The new behavior, to always signal, is
arguably a bug fix.

For rxrpc, the change causes the same function to be called repeatedly
for each queued packet (because the recv handler == sk_error_report).
It is likely that all packets will fail for the same reason (e.g.,
memory exhaustion).

This code runs without sk_lock held, so it is not safe to trust that
sk->sk_err is immutable inbetween releasing q->lock and the subsequent
test. Introduce int err just to avoid this potential race.
Signed-off-by: NWillem de Bruijn <willemb@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NTom Herbert <therbert@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Call skb_checksum_try_convert and skb_gro_checksum_try_convert
after checksum is found present and validated in the GRE header
for normal and GRO paths respectively.

In GRO path, call skb_gro_checksum_try_convert
Signed-off-by: NTom Herbert <therbert@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add support for doing CHECKSUM_UNNECESSARY to CHECKSUM_COMPLETE
conversion in UDP tunneling path.

In the normal UDP path, we call skb_checksum_try_convert after locating
the UDP socket. The check is that checksum conversion is enabled for
the socket (new flag in UDP socket) and that checksum field is
non-zero.

In the UDP GRO path, we call skb_gro_checksum_try_convert after
checksum is validated and checksum field is non-zero. Since this is
already in GRO we assume that checksum conversion is always wanted.
Signed-off-by: NTom Herbert <therbert@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This flag indicates that an invalid checksum was detected in the
packet. __skb_mark_checksum_bad helper function was added to set this.

Checksums can be marked bad from a driver or the GRO path (the latter
is implemented in this patch). csum_bad is checked in
__skb_checksum_validate_complete (i.e. calling that when ip_summed ==
CHECKSUM_NONE).

csum_bad works in conjunction with ip_summed value. In the case that
ip_summed is CHECKSUM_NONE and csum_bad is set, this implies that the
first (or next) checksum encountered in the packet is bad. When
ip_summed is CHECKSUM_UNNECESSARY, the first checksum after the last
one validated is bad. For example, if ip_summed == CHECKSUM_UNNECESSARY,
csum_level == 1, and csum_bad is set-- then the third checksum in the
packet is bad. In the normal path, the packet will be dropped when
processing the protocol layer of the bad checksum:
__skb_decr_checksum_unnecessary called twice for the good checksums
changing ip_summed to CHECKSUM_NONE so that
__skb_checksum_validate_complete is called to validate the third
checksum and that will fail since csum_bad is set.
Signed-off-by: NTom Herbert <therbert@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/dsa/dsa.c:624:20: sparse: symbol 'dsa_pack_type' was not declared.
Should it be static?

Fixes: 3e8a72d1 ("net: dsa: reduce number of protocol hooks")
Signed-off-by: NFengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix places where there is space before tab, long lines, and
awkward if(){, double spacing etc. Add blank line after declaration/initialization.
Signed-off-by: NStephen Hemminger <stephen@networkplumber.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Then testing the TX limits of the stack, then it is useful to
be-able to disable the do_gettimeofday() timetamping on every packet.

This implements a pktgen flag NO_TIMESTAMP which will disable this
call to do_gettimeofday().

The performance change on (my system E5-2695) with skb_clone=0, goes
from TX 2,423,751 pps to 2,567,165 pps with flag NO_TIMESTAMP. Thus,
the cost of do_gettimeofday() or saving is approx 23 nanosec.
Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

TIPC name table updates are distributed asynchronously in a cluster,
entailing a risk of certain race conditions. E.g., if two nodes
simultaneously issue conflicting (overlapping) publications, this may
not be detected until both publications have reached a third node, in
which case one of the publications will be silently dropped on that
node. Hence, we end up with an inconsistent name table.

In most cases this conflict is just a temporary race, e.g., one
node is issuing a publication under the assumption that a previous,
conflicting, publication has already been withdrawn by the other node.
However, because of the (rtt related) distributed update delay, this
may not yet hold true on all nodes. The symptom of this failure is a
syslog message: "tipc: Cannot publish {%u,%u,%u}, overlap error".

In this commit we add a resiliency queue at the receiving end of
the name table distributor. When insertion of an arriving publication
fails, we retain it in this queue for a short amount of time, assuming
that another update will arrive very soon and clear the conflict. If so
happens, we insert the publication, otherwise we drop it.

The (configurable) retention value defaults to 2000 ms. Knowing from
experience that the situation described above is extremely rare, there
is no risk that the queue will accumulate any large number of items.
Signed-off-by: NErik Hugne <erik.hugne@ericsson.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Acked-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We need to perform the same actions when processing deferred name
table updates, so this functionality is moved to a separate
function.
Signed-off-by: NErik Hugne <erik.hugne@ericsson.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Acked-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now fundamentally we can process lists of SKBs as cheaply
as single packets.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Just maintain the list properly by returning the head of the remaining
SKB list from dev_hard_start_xmit().
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

dev_hard_start_xmit() does two things, it first validates and
canonicalizes the SKB, then it actually sends it.

Make a set of helper functions for doing the first part.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For now it will always be false.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There is a slight policy change happening here as well.

The previous code would drop the entire rest of the GSO skb if any of
them got, for example, a congestion notification.

That makes no sense, anything NET_XMIT_MASK and below is something
like congestion or policing.  And in the congestion case it doesn't
even mean the packet was actually dropped.

Just continue until dev_xmit_complete() evaluates to false.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Hopefully making the code a bit easier to read and digest.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

That way we don't have to audit every call site to make sure it is
doing this properly.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

CHECKSUM_UNNECESSARY may be applied to the SCTP CRC so we need to
appropriate account for this by decrementing csum_level. This is
done by calling __skb_dec_checksum_unnecessary.
Signed-off-by: NTom Herbert <therbert@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Allow GRO path to "consume" checksums provided in CHECKSUM_UNNECESSARY
and to report new checksums verfied for use in fallback to normal
path.

Change GRO checksum path to track csum_level using a csum_cnt field
in NAPI_GRO_CB. On GRO initialization, if ip_summed is
CHECKSUM_UNNECESSARY set NAPI_GRO_CB(skb)->csum_cnt to
skb->csum_level + 1. For each checksum verified, decrement
NAPI_GRO_CB(skb)->csum_cnt while its greater than zero. If a checksum
is verfied and NAPI_GRO_CB(skb)->csum_cnt == 0, we have verified a
deeper checksum than originally indicated in skbuf so increment
csum_level (or initialize to CHECKSUM_UNNECESSARY if ip_summed is
CHECKSUM_NONE or CHECKSUM_COMPLETE).
Signed-off-by: NTom Herbert <therbert@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch:
 - Clarifies the specific requirements of devices returning
   CHECKSUM_UNNECESSARY (comments in skbuff.h).
 - Adds csum_level field to skbuff. This is used to express how
   many checksums are covered by CHECKSUM_UNNECESSARY (stores n - 1).
   This replaces the overloading of skb->encapsulation, that field is
   is now only used to indicate inner headers are valid.
 - Change __skb_checksum_validate_needed to "consume" each checksum
   as indicated by csum_level as layers of the the packet are parsed.
 - Remove skb_pop_rcv_encapsulation, no longer needed in the new
   csum_level model.
Signed-off-by: NTom Herbert <therbert@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 6c9808ce ("tipc: remove port_lock") accidentally involves
a potential bug: when tipc socket instance(tsk) is not got with given
reference number in tipc_sk_get(), tsk is set to NULL. Subsequently
we jump to exit label where to decrease socket reference counter
pointed by tsk pointer in tipc_sk_put(). However, As now tsk is NULL,
oops may happen because of touching a NULL pointer.
Signed-off-by: NYing Xue <ying.xue@windriver.com>
Acked-by: NErik Hugne <erik.hugne@ericsson.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Replace occurences of skb_get_queue_mapping() and follow-up
netdev_get_tx_queue() with an actual helper function.
Signed-off-by: NDaniel Borkmann <dborkman@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add support for the Broadcom Starfigther 2 switch chip using a DSA
driver. This switch driver supports the following features:

- configuration of the external switch port interface: MII, RevMII,
  RGMII and RGMII_NO_ID are supported
- support for the per-port MIB counters
- support for link interrupts for special ports (e.g: MoCA)
- powering up/down of switch memories to conserve power when ports are
  unused

Finally, update the compatible property for the DSA core code to match
our switch top-level compatible node.
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add support for the 4-bytes Broadcom tag that built-in switches such as
the Starfighter 2 might insert when receiving packets, or that we need
to insert while targetting specific switch ports. We use a fake local
EtherType value for this 4-bytes switch tag: ETH_P_BRCMTAG to make sure
we can assign DSA-specific network operations within the DSA drivers.
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Allow switch drivers to hook a PHY link update callback to perform
port-specific link work.
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Whenever libphy determines that the link status of a given PHY/port has
changed, allow to call into the switch driver link adjustment callback
so proper actions can be taken care of by the switch driver upon link
notification.
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In case switch port tagging is disabled (voluntarily, or the switch just
does not support it), allow us to continue using the defined set of
dsa_device_ops in net/dsa/slave.c.

We introduce dsa_protocol_is_tagged() to check whether we need to
override skb->protocol and go through the DSA-specifif packet_type
function, or if we just go on and receive the SKB through the normal
path.
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Modify the DSA slave interface to be bound to an arbitray PHY, not just
the ones that are available as child PHY devices of the switch MDIO bus.

This allows us for instance to have external PHYs connected to a
separate MDIO bus, but yet also connected to a given switch port.

Under certain configurations, the physical port mask might not be a 1:1
mapping to the MII PHYs mask. This is the case, if e.g: Port 1 of the
switch is used and connects to a PHY at a MDIO address different than 1.

Introduce a phys_mii_mask variable which allows driver to implement and
divert their own MDIO read/writes operations for a subset of the MDIO
PHY addresses.
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>