The fib metric memory in this case is static in the kernel image,
so we don't need to reference count it since it's never going
to go away on us.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If there are no explicit metrics attached to a route, hook
fi->fib_info up to dst_default_metrics.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is the initial gateway towards super-sharing metrics
if they are all set to zero for a route.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

TCP is going to record metrics for the connection,
so pre-COW the route metrics at route cache entry
creation time.

This avoids several atomic operations that have to
occur if we COW the metrics after the entry reaches
global visibility.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit c6d14c84 (net: Introduce for_each_netdev_rcu() iterator)
added a race in dev_seq_next().

The rcu_dereference() call should be done _before_ testing the end of
list, or we might return a wrong net_device if a concurrent thread
changes net_device list under us.

Note : discovered thanks to a sparse warning :

net/core/dev.c:3919:9: error: incompatible types in comparison expression
(different address spaces)
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
CC: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Please note that the IPSEC dst entry metrics keep using
the generic metrics COW'ing mechanism using kmalloc/kfree.

This gives the IPSEC routes an opportunity to use metrics
which are unique to their encapsulated paths.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

They are bogus.  The basic idea is that I wanted to make sure
that prefixed routes never bind to peers.

The test I used was whether RTF_CACHE was set.

But first of all, the RTF_CACHE flag is set at different spots
depending upon which ip6_rt_copy() caller you're talking about.

I've validated all of the code paths, and even in the future
where we bind peers more aggressively (for route metric COW'ing)
we never bind to prefix'd routes, only fully specified ones.
This even applies when addrconf or icmp6 routes are allocated.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

pskb_expand_head() triggers a kmemcheck warning when copy of
skb_shared_info is done in pskb_expand_head()

This is because destructor_arg field is not necessarily initialized at
this point. Add kmemcheck_annotate_variable() call in __alloc_skb() to
instruct kmemcheck this is a normal situation.

Resolves bugzilla.kernel.org 27212

Reference: https://bugzilla.kernel.org/show_bug.cgi?id=27212Reported-by: NChristian Casteyde <casteyde.christian@free.fr>
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

I'm testing an API that uses IFLA_AF_SPEC attribute.
In the rtnetlink core , the set_link_af() member
of the rtnl_af_ops struct receives the nested attribute
(as I expected), but the validate_link_af() member
receives the parent attribute.
IMO, this patch fixes this.
Signed-off-by: NKurt Van Dijck <kurt.van.dijck@eia.be>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/econet/af_econet.c: In function ‘econet_sendmsg’:
net/econet/af_econet.c:494: warning: label ‘error’ defined but not used
net/econet/af_econet.c:268: warning: unused variable ‘sk’
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Acked-by: NPhil Blundell <philb@gnu.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Set the RTAX_LOCKED metric to INETPEER_METRICS_NEW (basically,
all ones) on fresh inetpeer entries.

This way code can determine if default metrics have been loaded
in from a routing table entry already.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Routing metrics are now copy-on-write.

Initially a route entry points it's metrics at a read-only location.
If a routing table entry exists, it will point there.  Else it will
point at the all zero metric place-holder called 'dst_default_metrics'.

The writeability state of the metrics is stored in the low bits of the
metrics pointer, we have two bits left to spare if we want to store
more states.

For the initial implementation, COW is implemented simply via kmalloc.
However future enhancements will change this to place the writable
metrics somewhere else, in order to increase sharing.  Very likely
this "somewhere else" will be the inetpeer cache.

Note also that this means that metrics updates may transiently fail
if we cannot COW the metrics successfully.

But even by itself, this patch should decrease memory usage and
increase cache locality especially for routing workloads.  In those
cases the read-only metric copies stay in place and never get written
to.

TCP workloads where metrics get updated, and those rare cases where
PMTU triggers occur, will take a very slight performance hit.  But
that hit will be alleviated when the long-term writable metrics
move to a more sharable location.

Since the metrics storage went from a u32 array of RTAX_MAX entries to
what is essentially a pointer, some retooling of the dst_entry layout
was necessary.

Most importantly, we need to preserve the alignment of the reference
count so that it doesn't share cache lines with the read-mostly state,
as per Eric Dumazet's alignment assertion checks.

The only non-trivial bit here is the move of the 'flags' member into
the writeable cacheline.  This is OK since we are always accessing the
flags around the same moment when we made a modification to the
reference count.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Like ipv4, we have to propagate the ipv6 route peer into
the ipsec top-level route during instantiation.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For events that include only the local struct as
their parameter, we can use DECLARE_EVENT_CLASS
and save quite some binary size across segments
as well lines of code.

   text	   data	    bss	    dec	    hex	filename
 375745	  19296	    916	 395957	  60ab5	mac80211.ko.before
 367473	  17888	    916	 386277	  5e4e5	mac80211.ko.after
  -8272   -1408       0   -9680   -25d0 delta

Some more tracepoints with identical arguments
could be combined like this but for now this is
the one that benefits most.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

mqprio_dump() should make sure all fields of struct tc_mqprio_qopt are
initialized.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
CC: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes a bug that causes TCP RST packets to be generated
on otherwise correctly behaved applications, e.g., no unread data
on close,..., etc. To trigger the bug, at least two conditions must
be met:

1. The FIN flag is set on the last data packet, i.e., it's not on a
separate, FIN only packet.
2. The size of the last data chunk on the receive side matches
exactly with the size of buffer posted by the receiver, and the
receiver closes the socket without any further read attempt.

This bug was first noticed on our netperf based testbed for our IW10
proposal to IETF where a large number of RST packets were observed.
netperf's read side code meets the condition 2 above 100%.

Before the fix, tcp_data_queue() will queue the last skb that meets
condition 1 to sk_receive_queue even though it has fully copied out
(skb_copy_datagram_iovec()) the data. Then if condition 2 is also met,
tcp_recvmsg() often returns all the copied out data successfully
without actually consuming the skb, due to a check
"if ((chunk = len - tp->ucopy.len) != 0) {"
and
"len -= chunk;"
after tcp_prequeue_process() that causes "len" to become 0 and an
early exit from the big while loop.

I don't see any reason not to free the skb whose data have been fully
consumed in tcp_data_queue(), regardless of the FIN flag.  We won't
get there if MSG_PEEK is on. Am I missing some arcane cases related
to urgent data?
Signed-off-by: NH.K. Jerry Chu <hkchu@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Some drivers (e.g. ath9k) do not always disable beacons when they're
supposed to. When an interface is changed using the change_interface op,
the mode specific sdata part is in an undefined state and trying to
get a beacon at this point can produce weird crashes.

To fix this, add a check for ieee80211_sdata_running before using
anything from the sdata.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Cc: stable@kernel.org
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

We spend lot of time clearing pages in pktgen.
(Or not clearing them on ipv6 and leaking kernel memory)

Since we dont modify them, we can use one zeroed page, and get
references on it. This page can use NUMA affinity as well.

Define pktgen_finalize_skb() helper, used both in ipv4 and ipv6

Results using skbs with one frag :

Before patch :

Result: OK: 608980458(c608978520+d1938) nsec, 1000000000
(100byte,1frags)
  1642088pps 1313Mb/sec (1313670400bps) errors: 0

After patch :

Result: OK: 345285014(c345283891+d1123) nsec, 1000000000
(100byte,1frags)
  2896158pps 2316Mb/sec (2316926400bps) errors: 0
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts the following set of commits:

d1ed113f ("ipv6: remove duplicate neigh_ifdown")
29ba5fed ("ipv6: don't flush routes when setting loopback down")
9d82ca98 ("ipv6: fix missing in6_ifa_put in addrconf")
2de79570 ("ipv6: addrconf: don't remove address state on ifdown if the address is being kept")
8595805a ("IPv6: only notify protocols if address is compeletely gone")
27bdb2ab ("IPv6: keep tentative addresses in hash table")
93fa159a ("IPv6: keep route for tentative address")
8f37ada5 ("IPv6: fix race between cleanup and add/delete address")
84e8b803 ("IPv6: addrconf notify when address is unavailable")
dc2b99f7 ("IPv6: keep permanent addresses on admin down")

because the core semantic change to ipv6 address handling on ifdown
has broken some things, in particular "disable_ipv6" sysctl handling.

Stephen has made several attempts to get things back in working order,
but nothing has restored disable_ipv6 fully yet.
Reported-by: NEric W. Biederman <ebiederm@xmission.com>
Tested-by: NEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The group of a network device can be queried or changed from userspace
using sysfs.

For example, considering sysfs mounted in /sys, one can change the group
that interface lo belongs to:
	echo 1 > /sys/class/net/lo/group
Signed-off-by: NVlad Dogaru <ddvlad@rosedu.org>
Acked-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There is a conflict between commit b00916b1 and a77f5db3. This patch resolves
the conflict by clearing the heap allocation in ethtool_get_regs().

Cc: stable@kernel.org
Signed-off-by: NEugene Teo <eugeneteo@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Do not handle PMTU vs. route lookup creation any differently
wrt. offlink routes, always clone them.
Reported-by: NPK <runningdoglackey@yahoo.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Reduce printk() levels to KERN_INFO in netdev_fix_features() as this will
be used by ethtool and might spam dmesg unnecessarily.

This converts the function to use netdev_info() instead of plain printk().

As a side effect, bonding and bridge devices will now log dropped features
on every slave device change.
Signed-off-by: NMichał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Quoting Ben Hutchings: we presumably won't be defining features that
can only be enabled on 64-bit architectures.

Occurences found by `grep -r` on net/, drivers/net, include/

[ Move features and vlan_features next to each other in
  struct netdev, as per Eric Dumazet's suggestion -DaveM ]
Signed-off-by: NMichał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NMichał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The IEEE get/set app handlers use generic routines and do not
require the net_device to implement the dcbnl_ops routines. This
patch makes it symmetric so user space and drivers do not have
to handle the CEE version and IEEE DCBx versions differently.
Signed-off-by: NJohn Fastabend <john.r.fastabend@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Allow drivers for multiqueue hardware with flow filter tables to
accelerate RFS.  The driver must:

1. Set net_device::rx_cpu_rmap to a cpu_rmap of the RX completion
IRQs (in queue order).  This will provide a mapping from CPUs to the
queues for which completions are handled nearest to them.

2. Implement net_device_ops::ndo_rx_flow_steer.  This operation adds
or replaces a filter steering the given flow to the given RX queue, if
possible.

3. Periodically remove filters for which rps_may_expire_flow() returns
true.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit a8b690f9 (tcp: Fix slowness in read /proc/net/tcp)
introduced a bug in handling of SYN_RECV sockets.

st->offset represents number of sockets found since beginning of
listening_hash[st->bucket].

We should not reset st->offset when iterating through
syn_table[st->sbucket], or else if more than ~25 sockets (if
PAGE_SIZE=4096) are in SYN_RECV state, we exit from listening_get_next()
with a too small st->offset

Next time we enter tcp_seek_last_pos(), we are not able to seek past
already found sockets.
Reported-by: NPK <runningdoglackey@yahoo.com>
CC: Tom Herbert <therbert@google.com>
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Family was hard-coded to AF_INET but should be daddr->family.

This fixes crashes when unlinking ipv6 peer entries, since the
unlink code was looking up the base pointer properly.
Reported-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Suppose that several linear skbs of the same flow were received by GRO. They
were thus merged into one skb with a frag_list. Then a new skb of the same flow
arrives, but it is a paged skb with data starting in its frags[].

Before adding the skb to the frag_list skb_gro_receive() will of course adjust
the skb to throw away the headers. It correctly modifies the page_offset and
size of the frag, but it leaves incorrect information in the skb:
 ->data_len is not decreased at all.
 ->len is decreased only by headlen, as if no change were done to the frag.
Later in a receiving process this causes skb_copy_datagram_iovec() to return
-EFAULT and this is seen in userspace as the result of the recv() syscall.

In practice the bug can be reproduced with the sfc driver. By default the
driver uses an adaptive scheme when it switches between using
napi_gro_receive() (with skbs) and napi_gro_frags() (with pages). The bug is
reproduced when under rx load with enough successful GRO merging the driver
decides to switch from the former to the latter.

Manual control is also possible, so reproducing this is easy with netcat:
 - on machine1 (with sfc): nc -l 12345 > /dev/null
 - on machine2: nc machine1 12345 < /dev/zero
 - on machine1:
   echo 1 > /sys/module/sfc/parameters/rx_alloc_method  # use skbs
   echo 2 > /sys/module/sfc/parameters/rx_alloc_method  # use pages
 - See that nc has quit suddenly.

[v2: Modified by Eric Dumazet to avoid advancing skb->data past the end
     and to use a temporary variable.]
Signed-off-by: NMichal Schmidt <mschmidt@redhat.com>
Acked-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 941666c2 "net: RCU conversion of dev_getbyhwaddr() and
arp_ioctl()" introduced a regression, reported by Jamie Heilman.
"arp -Ds 192.168.2.41 eth0 pub" triggered the ASSERT_RTNL() assert
in pneigh_lookup()

Removing RTNL requirement from arp_ioctl() was a mistake, just revert
that part.
Reported-by: NJamie Heilman <jamie@audible.transient.net>
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

You always needed them when you were a module, but the builtin versions
of the macros used to be more lenient.
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Now qdisc stab is handled before TCQ_F_CAN_BYPASS test in
__dev_xmit_skb(), we can generalize TCQ_F_CAN_BYPASS to other qdiscs
than pfifo_fast : pfifo, bfifo, pfifo_head_drop and sfq

SFQ is special because it can have external classifiers, and in these
cases, we cannot bypass queue discipline (packet could be dropped by
classifier) without admin asking it, or further changes.

Its worth doing this, especially for SFQ, avoiding dirtying memory in
case no packets are already waiting in queue.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Acked-by: NJohn Fastabend <john.r.fastabend@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Extend channel to frequency mapping for 802.11j Japan 4.9GHz band, according to
IEEE802.11 section 17.3.8.3.2 and Annex J. Because there are now overlapping
channel numbers in the 2GHz and 5GHz band we can't map from channel to
frequency without knowing the band. This is no problem as in most contexts we
know the band. In places where we don't know the band (and WEXT compatibility)
we assume the 2GHz band for channels below 14.

This patch does not implement all channel to frequency mappings defined in
802.11, it's just an extension for 802.11j 20MHz channels. 5MHz and 10MHz
channels as well as 802.11y channels have been omitted.

The following drivers have been updated to reflect the API changes:
iwl-3945, iwl-agn, iwmc3200wifi, libertas, mwl8k, rt2x00, wl1251, wl12xx.
The drivers have been compile-tested only.
Signed-off-by: NBruno Randolf <br1@einfach.org>
Signed-off-by: NBrian Prodoehl <bprodoehl@gmail.com>
Acked-by: NLuciano Coelho <coelho@ti.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This particular error isn't about multicast.
Signed-off-by: NBen Greear <greearb@candelatech.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

In commit 44b82883 (net_sched: pfifo_head_drop problem), we fixed
a problem with pfifo_head drops that incorrectly decreased
sch->bstats.bytes and sch->bstats.packets

Several qdiscs (CHOKe, SFQ, pfifo_head, ...) are able to drop a
previously enqueued packet, and bstats cannot be changed, so
bstats/rates are not accurate (over estimated)

This patch changes the qdisc_bstats updates to be done at dequeue() time
instead of enqueue() time. bstats counters no longer account for dropped
frames, and rates are more correct, since enqueue() bursts dont have
effect on dequeue() rate.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Acked-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

rtnl_group_changelink() is invoked by rtnl_newlink() before the link
attributes have been validated. Additionally the group changes are
performed even if NLM_F_CREATE is specified and a new link is
created, while more reasonable semantics would be to set the group
value on the newly created link.

Fix both problems by moving the rtnl_group_changelink() invocation
down to the handling of non-existant links without NLM_F_CREATE()
and add a dev_set_group() call to rtnl_create_link().
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Acked-by: NVlad Dogaru <ddvlad@rosedu.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The meaning of CONFIG_EMBEDDED has long since been obsoleted; the option
is used to configure any non-standard kernel with a much larger scope than
only small devices.

This patch renames the option to CONFIG_EXPERT in init/Kconfig and fixes
references to the option throughout the kernel.  A new CONFIG_EMBEDDED
option is added that automatically selects CONFIG_EXPERT when enabled and
can be used in the future to isolate options that should only be
considered for embedded systems (RISC architectures, SLOB, etc).

Calling the option "EXPERT" more accurately represents its intention: only
expert users who understand the impact of the configuration changes they
are making should enable it.
Reviewed-by: NIngo Molnar <mingo@elte.hu>
Acked-by: NDavid Woodhouse <david.woodhouse@intel.com>
Signed-off-by: NDavid Rientjes <rientjes@google.com>
Cc: Greg KH <gregkh@suse.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Robin Holt <holt@sgi.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove sparse warnings, using a function typedef to be able to use __rcu
annotation on mh_filter pointer.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>