In commit dd3f9e70
("tipc: add packet sequence number at instant of transmission") we
made a change with the consequence that packets in the link backlog
queue don't contain valid sequence numbers.

However, when we create a link protocol message, we still use the
sequence number of the first packet in the backlog, if there is any,
as "next_sent" indicator in the message. This may entail unnecessary
retransissions or stale packet transmission when there is very low
traffic on the link.

This commit fixes this issue by only using the current value of
tipc_link::snd_nxt as indicator.
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

make C=2 CF=-D__CHECK_ENDIAN__ net/core/utils.o
...
net/core/utils.c:307:72: warning: incorrect type in argument 2 (different base types)
net/core/utils.c:307:72:    expected restricted __wsum [usertype] addend
net/core/utils.c:307:72:    got restricted __be32 [usertype] from
net/core/utils.c:308:34: warning: incorrect type in argument 2 (different base types)
net/core/utils.c:308:34:    expected restricted __wsum [usertype] addend
net/core/utils.c:308:34:    got restricted __be32 [usertype] to
net/core/utils.c:310:70: warning: incorrect type in argument 2 (different base types)
net/core/utils.c:310:70:    expected restricted __wsum [usertype] addend
net/core/utils.c:310:70:    got restricted __be32 [usertype] from
net/core/utils.c:310:77: warning: incorrect type in argument 2 (different base types)
net/core/utils.c:310:77:    expected restricted __wsum [usertype] addend
net/core/utils.c:310:77:    got restricted __be32 [usertype] to
net/core/utils.c:312:72: warning: incorrect type in argument 2 (different base types)
net/core/utils.c:312:72:    expected restricted __wsum [usertype] addend
net/core/utils.c:312:72:    got restricted __be32 [usertype] from
net/core/utils.c:313:35: warning: incorrect type in argument 2 (different base types)
net/core/utils.c:313:35:    expected restricted __wsum [usertype] addend
net/core/utils.c:313:35:    got restricted __be32 [usertype] to

Note we can use csum_replace4() helper

Fixes: 58e3cac5 ("net: optimise inet_proto_csum_replace4()")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

make C=2 CF=-D__CHECK_ENDIAN__ net/core/secure_seq.o
net/core/secure_seq.c:157:50: warning: restricted __be32 degrades to
integer
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Check in fdb_add_entry() if the source port should learn, similar
check is used in br_fdb_update.
Note that new fdb entries which are added manually or
as local ones are still permitted.
This patch has been tested by running traffic via a bridge port and
switching the port's state, also by manually adding/removing entries
from the bridge's fdb.
Signed-off-by: NWilson Kok <wkok@cumulusnetworks.com>
Signed-off-by: NNikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/core/pktgen.c:2672:43: warning: incorrect type in assignment (different base types)
net/core/pktgen.c:2672:43:    expected unsigned short [unsigned] [short] [usertype] <noident>
net/core/pktgen.c:2672:43:    got restricted __be16 [usertype] protocol

Let's use proper struct ethhdr instead of hard coding everything.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ipv6_select_ident() returns a 32bit value in network order.

Fixes: 286c2349 ("ipv6: Clean up ipv6_select_ident() and ip6_fragment()")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Acked-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

API compliance scanning with coccinelle flagged:
./net/irda/timer.c:63:35-37: use of msecs_to_jiffies probably perferable

Converting milliseconds to jiffies by "val * HZ / 1000" technically
is not a clean solution as it does not handle all corner cases correctly.
By changing the conversion to use msecs_to_jiffies(val) conversion is
correct in all cases. Further the () around the arithmetic expression
was dropped.

Patch was compile tested for x86_64_defconfig + CONFIG_IRDA=m

Patch is against 4.1-rc4 (localversion-next is -next-20150522)
Signed-off-by: NNicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Network managers like netifd (used in OpenWRT for instance) try to
configure interface options after creation but before setting the
interface up.

Unfortunately the sysfs / bridge currently only allows to configure the
hash_max and multicast_router options when the bridge interface is up.
But since br_multicast_init() doesn't start any timers and only sets
default values and initializes timers it should be save to reconfigure
the default values after that, before things actually get active after
the bridge is set up.
Signed-off-by: NLinus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

since commit 6aafeef0 ("netfilter: push reasm skb through instead of
original frag skbs") we will end up sometimes re-fragmenting skbs
that we've reassembled.

ipv6 defrag preserves the original skbs using the skb frag list, i.e. as long
as the skb frag list is preserved there is no problem since we keep
original geometry of fragments intact.

However, in the rare case where the frag list is munged or skb
is linearized, we might send larger fragments than what we originally
received.

A router in the path might then send packet-too-big errors even if
sender never sent fragments exceeding the reported mtu:

mtu 1500 - 1500:1400 - 1400:1280 - 1280
     A         R1         R2        B

1 - A sends to B, fragment size 1400
2 - R2 sends pkttoobig error for 1280
3 - A sends to B, fragment size 1280
4 - R2 sends pkttoobig error for 1280 again because it sees fragments of size 1400.

make sure ip6_fragment always caps MTU at largest packet size seen
when defragmented skb is forwarded.
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After the patch
'ipv6: Only create RTF_CACHE routes after encountering pmtu exception',
we need to compensate the performance hit (bouncing dst->__refcnt).
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch breaks up ip6_rt_copy() into ip6_rt_copy_init() and
ip6_rt_cache_alloc().

In the later patch, we need to create a percpu rt6_info copy. Hence,
refactor the common rt6_info init codes to ip6_rt_copy_init().
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch keeps track of the DST_NOCACHE routes in a list and replaces its
dev with loopback during the iface down/unregister event.
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch always creates RTF_CACHE clone with DST_NOCACHE
when FLOWI_FLAG_KNOWN_NH is set so that the rt6i_dst is set to
the fl6->daddr.
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Acked-by: NJulian Anastasov <ja@ssi.bg>
Tested-by: NJulian Anastasov <ja@ssi.bg>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The neighbor look-up used to depend on the rt6i_gateway (if
there is a gateway) or the rt6i_dst (if it is a RTF_CACHE clone)
as the nexthop address.  Note that rt6i_dst is set to fl6->daddr
for the RTF_CACHE clone where fl6->daddr is the one used to do
the route look-up.

Now, we only create RTF_CACHE clone after encountering exception.
When doing the neighbor look-up with a route that is neither a gateway
nor a RTF_CACHE clone, the daddr in skb will be used as the nexthop.

In some cases, the daddr in skb is not the one used to do
the route look-up.  One example is in ip_vs_dr_xmit_v6() where the
real nexthop server address is different from the one in the skb.

This patch is going to follow the IPv4 approach and ask the
ip6_pol_route() callers to set the FLOWI_FLAG_KNOWN_NH properly.

In the next patch, ip6_pol_route() will honor the FLOWI_FLAG_KNOWN_NH
and create a RTF_CACHE clone.
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Acked-by: NJulian Anastasov <ja@ssi.bg>
Tested-by: NJulian Anastasov <ja@ssi.bg>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Instead of doing the rt6->rt6i_node check whenever we need
to get the route's cookie.  Refactor it into rt6_get_cookie().
It is a prep work to handle FLOWI_FLAG_KNOWN_NH and also
percpu rt6_info later.
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch creates a RTF_CACHE routes only after encountering a pmtu
exception.

After ip6_rt_update_pmtu() has inserted the RTF_CACHE route to the fib6
tree, the rt->rt6i_node->fn_sernum is bumped which will fail the
ip6_dst_check() and trigger a relookup.
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A prep work for creating RTF_CACHE on exception only.  After this
patch, the same condition (rt->rt6i_flags & (RTF_NONEXTHOP | RTF_GATEWAY))
is checked twice. This redundancy will be removed in the later patch.
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When creating a RTF_CACHE route, RTF_ANYCAST is set based on rt6i_dst.
Also, rt6i_gateway is always set to the nexthop while the nexthop
could be a gateway or the rt6i_dst.addr.

After removing the rt6i_dst and rt6i_src dependency in the last patch,
we also need to stop the caller from depending on rt6i_gateway and
RTF_ANYCAST.
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch removes the assumptions that the returned rt is always
a RTF_CACHE entry with the rt6i_dst and rt6i_src containing the
destination and source address.  The dst and src can be recovered from
the calling site.

We may consider to rename (rt6i_dst, rt6i_src) to
(rt6i_key_dst, rt6i_key_src) later.
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Reviewed-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch changes the ipv6_select_ident() signature to return a
fragment id instead of taking a whole frag_hdr as a param to
only set the frag_hdr->identification.

It also cleans up ip6_fragment() to obtain the fragment id at the
beginning instead of using multiple "if" later to check fragment id
has been generated or not.
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Send icmp pmtu error if we find that the largest fragment of df-skb
exceeded the output path mtu.

The ip output path will still catch this later on but we can avoid the
forward/postrouting hook traversal by rejecting right away.

This is what ipv6 already does.
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

unix_stream_recvmsg is refactored to unix_stream_read_generic in this
patch and enhanced to deal with pipe splicing. The refactoring is
inneglible, we mostly have to deal with a non-existing struct msghdr
argument.
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Prepare skb_splice_bits to be able to deal with AF_UNIX sockets.

AF_UNIX sockets don't use lock_sock/release_sock and thus we have to
use a callback to make the locking and unlocking configureable.
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch implements sendpage support for AF_UNIX SOCK_STREAM
sockets. This is also required for a complete splice implementation.

The implementation is a bit tricky because we append to already existing
skbs and so have to hold unix_sk->readlock to protect the reading side
from either advancing UNIXCB.consumed or freeing the skb at the socket
receive tail.
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Giving /proc/net/pktgen/pgctrl an invalid command just returns shell
success and prints a warning in dmesg.  This is not very useful for
shell scripting, as it can only detect the error by parsing dmesg.

Instead return -EINVAL when the command is unknown, as this provides
userspace shell scripting a way of detecting this.

Also bump version tag to 2.75, because (1) reading /proc/net/pktgen/pgctrl
output this version number which would allow to detect this small
semantic change, and (2) because the pktgen version tag have not been
updated since 2010.
Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Too many spaces were introduced in commit 63adc6fb ("pktgen: cleanup
checkpatch warnings"), thus misaligning "src_min:" to other columns.

Fixes: 63adc6fb ("pktgen: cleanup checkpatch warnings")
Signed-off-by: NJesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Following lockdep splat was reported :

[   29.382286] ===============================
[   29.382315] [ INFO: suspicious RCU usage. ]
[   29.382344] 4.1.0-0.rc0.git11.1.fc23.x86_64 #1 Not tainted
[   29.382380] -------------------------------
[   29.382409] net/bridge/br_private.h:626 suspicious
rcu_dereference_check() usage!
[   29.382455]
               other info that might help us debug this:

[   29.382507]
               rcu_scheduler_active = 1, debug_locks = 0
[   29.382549] 2 locks held by swapper/0/0:
[   29.382576]  #0:  (((&p->forward_delay_timer))){+.-...}, at:
[<ffffffff81139f75>] call_timer_fn+0x5/0x4f0
[   29.382660]  #1:  (&(&br->lock)->rlock){+.-...}, at:
[<ffffffffa0450dc1>] br_forward_delay_timer_expired+0x31/0x140
[bridge]
[   29.382754]
               stack backtrace:
[   29.382787] CPU: 0 PID: 0 Comm: swapper/0 Not tainted
4.1.0-0.rc0.git11.1.fc23.x86_64 #1
[   29.382838] Hardware name: LENOVO 422916G/LENOVO, BIOS A1KT53AUS 04/07/2015
[   29.382882]  0000000000000000 3ebfc20364115825 ffff880666603c48
ffffffff81892d4b
[   29.382943]  0000000000000000 ffffffff81e124e0 ffff880666603c78
ffffffff8110bcd7
[   29.383004]  ffff8800785c9d00 ffff88065485ac58 ffff880c62002800
ffff880c5fc88ac0
[   29.383065] Call Trace:
[   29.383084]  <IRQ>  [<ffffffff81892d4b>] dump_stack+0x4c/0x65
[   29.383130]  [<ffffffff8110bcd7>] lockdep_rcu_suspicious+0xe7/0x120
[   29.383178]  [<ffffffffa04520f9>] br_fill_ifinfo+0x4a9/0x6a0 [bridge]
[   29.383225]  [<ffffffffa045266b>] br_ifinfo_notify+0x11b/0x4b0 [bridge]
[   29.383271]  [<ffffffffa0450d90>] ? br_hold_timer_expired+0x70/0x70 [bridge]
[   29.383320]  [<ffffffffa0450de8>]
br_forward_delay_timer_expired+0x58/0x140 [bridge]
[   29.383371]  [<ffffffffa0450d90>] ? br_hold_timer_expired+0x70/0x70 [bridge]
[   29.383416]  [<ffffffff8113a033>] call_timer_fn+0xc3/0x4f0
[   29.383454]  [<ffffffff81139f75>] ? call_timer_fn+0x5/0x4f0
[   29.383493]  [<ffffffff8110a90f>] ? lock_release_holdtime.part.29+0xf/0x200
[   29.383541]  [<ffffffffa0450d90>] ? br_hold_timer_expired+0x70/0x70 [bridge]
[   29.383587]  [<ffffffff8113a6a4>] run_timer_softirq+0x244/0x490
[   29.383629]  [<ffffffff810b68cc>] __do_softirq+0xec/0x670
[   29.383666]  [<ffffffff810b70d5>] irq_exit+0x145/0x150
[   29.383703]  [<ffffffff8189f506>] smp_apic_timer_interrupt+0x46/0x60
[   29.383744]  [<ffffffff8189d523>] apic_timer_interrupt+0x73/0x80
[   29.383782]  <EOI>  [<ffffffff816f131f>] ? cpuidle_enter_state+0x5f/0x2f0
[   29.383832]  [<ffffffff816f131b>] ? cpuidle_enter_state+0x5b/0x2f0

Problem here is that br_forward_delay_timer_expired() is a timer
handler, calling br_ifinfo_notify() which assumes either rcu_read_lock()
or RTNL are held.

Simplest fix seems to add rcu read lock section.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reported-by: NJosh Boyer <jwboyer@fedoraproject.org>
Reported-by: NDominick Grift <dac.override@gmail.com>
Cc: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When trying to configure the settings for PHY1, using commands
like 'ethtool -s eth0 phyad 1 speed 100', the 'ethtool' seems to
modify other settings apart from the speed of the PHY1, in the
above case.

The ethtool seems to query the settings for PHY0, and use this
as the base to apply the new settings to the PHY1. This is
causing the other settings of the PHY 1 to be wrongly
configured.

The issue is caused by the '_ethtool_get_settings()' API, which
gets called because of the 'ETHTOOL_GSET' command, is clearing
the 'cmd' pointer (of type 'struct ethtool_cmd') by calling
memset. This clears all the parameters (if any) passed for the
'ETHTOOL_GSET' cmd. So the driver's callback is always invoked
with 'cmd->phy_address' as '0'.

The '_ethtool_get_settings()' is called from other files in the
'net/core'. So the fix is applied to the 'ethtool_get_settings()'
which is only called in the context of the 'ethtool'.
Signed-off-by: NArun Parameswaran <aparames@broadcom.com>
Reviewed-by: NRay Jui <rjui@broadcom.com>
Reviewed-by: NScott Branden <sbranden@broadcom.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When more than a multicast address is present in a MLDv2 report, all but
the first address is ignored, because the code breaks out of the loop if
there has not been an error adding that address.

This has caused failures when two guests connected through the bridge
tried to communicate using IPv6. Neighbor discoveries would not be
transmitted to the other guest when both used a link-local address and a
static address.

This only happens when there is a MLDv2 querier in the network.

The fix will only break out of the loop when there is a failure adding a
multicast address.

The mdb before the patch:

dev ovirtmgmt port vnet0 grp ff02::1:ff7d:6603 temp
dev ovirtmgmt port vnet1 grp ff02::1:ff7d:6604 temp
dev ovirtmgmt port bond0.86 grp ff02::2 temp

After the patch:

dev ovirtmgmt port vnet0 grp ff02::1:ff7d:6603 temp
dev ovirtmgmt port vnet1 grp ff02::1:ff7d:6604 temp
dev ovirtmgmt port bond0.86 grp ff02::fb temp
dev ovirtmgmt port bond0.86 grp ff02::2 temp
dev ovirtmgmt port bond0.86 grp ff02::d temp
dev ovirtmgmt port vnet0 grp ff02::1:ff00:76 temp
dev ovirtmgmt port bond0.86 grp ff02::16 temp
dev ovirtmgmt port vnet1 grp ff02::1:ff00:77 temp
dev ovirtmgmt port bond0.86 grp ff02::1:ff00:def temp
dev ovirtmgmt port bond0.86 grp ff02::1:ffa1:40bf temp

Fixes: 08b202b6 ("bridge br_multicast: IPv6 MLD support.")
Reported-by: NRik Theys <Rik.Theys@esat.kuleuven.be>
Signed-off-by: NThadeu Lima de Souza Cascardo <cascardo@redhat.com>
Tested-by: NRik Theys <Rik.Theys@esat.kuleuven.be>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When replacing an IPv4 route, tb_id member of the new fib_alias
structure is not set in the replace code path so that the new route is
ignored.

Fixes: 0ddcf43d ("ipv4: FIB Local/MAIN table collapse")
Signed-off-by: NMichal Kubecek <mkubecek@suse.cz>
Acked-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ip_error does not check if in_dev is NULL before dereferencing it.

IThe following sequence of calls is possible:
CPU A                          CPU B
ip_rcv_finish
    ip_route_input_noref()
        ip_route_input_slow()
                               inetdev_destroy()
    dst_input()

With the result that a network device can be destroyed while processing
an input packet.

A crash was triggered with only unicast packets in flight, and
forwarding enabled on the only network device.   The error condition
was created by the removal of the network device.

As such it is likely the that error code was -EHOSTUNREACH, and the
action taken by ip_error (if in_dev had been accessible) would have
been to not increment any counters and to have tried and likely failed
to send an icmp error as the network device is going away.

Therefore handle this weird case by just dropping the packet if
!in_dev.  It will result in dropping the packet sooner, and will not
result in an actual change of behavior.

Fixes: 251da413 ("ipv4: Cache ip_error() routes even when not forwarding.")
Reported-by: NVittorio Gambaletta <linuxbugs@vittgam.net>
Tested-by: NVittorio Gambaletta <linuxbugs@vittgam.net>
Signed-off-by: NVittorio Gambaletta <linuxbugs@vittgam.net>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This restored previous behaviour. If caller does not want ports to be
filled, we should not break.

Fixes: 06635a35 ("flow_dissect: use programable dissector in skb_flow_dissect and friends")
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Taking socket spinlock in tcp_get_info() can deadlock, as
inet_diag_dump_icsk() holds the &hashinfo->ehash_locks[i],
while packet processing can use the reverse locking order.

We could avoid this locking for TCP_LISTEN states, but lockdep would
certainly get confused as all TCP sockets share same lockdep classes.

[  523.722504] ======================================================
[  523.728706] [ INFO: possible circular locking dependency detected ]
[  523.734990] 4.1.0-dbg-DEV #1676 Not tainted
[  523.739202] -------------------------------------------------------
[  523.745474] ss/18032 is trying to acquire lock:
[  523.750002]  (slock-AF_INET){+.-...}, at: [<ffffffff81669d44>] tcp_get_info+0x2c4/0x360
[  523.758129]
[  523.758129] but task is already holding lock:
[  523.763968]  (&(&hashinfo->ehash_locks[i])->rlock){+.-...}, at: [<ffffffff816bcb75>] inet_diag_dump_icsk+0x1d5/0x6c0
[  523.774661]
[  523.774661] which lock already depends on the new lock.
[  523.774661]
[  523.782850]
[  523.782850] the existing dependency chain (in reverse order) is:
[  523.790326]
-> #1 (&(&hashinfo->ehash_locks[i])->rlock){+.-...}:
[  523.796599]        [<ffffffff811126bb>] lock_acquire+0xbb/0x270
[  523.802565]        [<ffffffff816f5868>] _raw_spin_lock+0x38/0x50
[  523.808628]        [<ffffffff81665af8>] __inet_hash_nolisten+0x78/0x110
[  523.815273]        [<ffffffff816819db>] tcp_v4_syn_recv_sock+0x24b/0x350
[  523.822067]        [<ffffffff81684d41>] tcp_check_req+0x3c1/0x500
[  523.828199]        [<ffffffff81682d09>] tcp_v4_do_rcv+0x239/0x3d0
[  523.834331]        [<ffffffff816842fe>] tcp_v4_rcv+0xa8e/0xc10
[  523.840202]        [<ffffffff81658fa3>] ip_local_deliver_finish+0x133/0x3e0
[  523.847214]        [<ffffffff81659a9a>] ip_local_deliver+0xaa/0xc0
[  523.853440]        [<ffffffff816593b8>] ip_rcv_finish+0x168/0x5c0
[  523.859624]        [<ffffffff81659db7>] ip_rcv+0x307/0x420

Lets use u64_sync infrastructure instead. As a bonus, 64bit
arches get optimized, as these are nop for them.

Fixes: 0df48c26 ("tcp: add tcpi_bytes_acked to tcp_info")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch tracks the total number of inbound and outbound segments on a
TCP socket. One may use this number to have an idea on connection
quality when compared against the retransmissions.

RFC4898 named these : tcpEStatsPerfSegsIn and tcpEStatsPerfSegsOut

These are a 32bit field each and can be fetched both from TCP_INFO
getsockopt() if one has a handle on a TCP socket, or from inet_diag
netlink facility (iproute2/ss patch will follow)

Note that tp->segs_out was placed near tp->snd_nxt for good data
locality and minimal performance impact, while tp->segs_in was placed
near tp->bytes_received for the same reason.

Join work with Eric Dumazet.

Note that received SYN are accounted on the listener, but sent SYNACK
are not accounted.
Signed-off-by: NMarcelo Ricardo Leitner <mleitner@redhat.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ip -6 addr add dead::1/128 dev eth0
sleep 5
ip -6 route add default via dead::1/128
-> fails
ip -6 addr add dead::1/128 dev eth0
ip -6 route add default via dead::1/128
-> succeeds

reason is that if (nonsensensical) route above is added,
dead::1 is still subject to DAD, so the route lookup will
pick eth0 as outdev due to the prefix route that is added before
DAD work is started.

Add explicit test that checks if nexthop gateway is a local address.

Link: https://bugzilla.redhat.com/show_bug.cgi?id=1167969Signed-off-by: NFlorian Westphal <fw@strlen.de>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

inet_csk_get_port() randomization effort tends to spread
sockets on all the available range (ip_local_port_range)

This is unfortunate because SO_REUSEADDR sockets have
less requirements than non SO_REUSEADDR ones.

If an application uses SO_REUSEADDR hint, it is to try to
allow source ports being shared.

So instead of picking a random port number in ip_local_port_range,
lets try first in first half of the range.

This gives more chances to use upper half of the range for the
sockets with strong requirements (not using SO_REUSEADDR)

Note this patch does not add a new sysctl, and only changes
the way we try to pick port number.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Marcelo Ricardo Leitner <mleitner@redhat.com>
Cc: Flavio Leitner <fbl@redhat.com>
Acked-by: NFlavio Leitner <fbl@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We no longer need bsocket atomic counter, as inet_csk_get_port()
calls bind_conflict() regardless of its value, after commit
2b05ad33 ("tcp: bind() fix autoselection to share ports")

This patch removes overhead of maintaining this counter and
double inet_csk_get_port() calls under pressure.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Marcelo Ricardo Leitner <mleitner@redhat.com>
Cc: Flavio Leitner <fbl@redhat.com>
Acked-by: NFlavio Leitner <fbl@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We currently rely on the setting of SOCK_NOSPACE in the write()
path to ensure that we wake up any epoll edge trigger waiters when
acks return to free space in the write queue. However, if we fail
to allocate even a single skb in the write queue, we could end up
waiting indefinitely.

Fix this by explicitly issuing a wakeup when we detect the condition
of an empty write queue and a return value of -EAGAIN. This allows
userspace to re-try as we expect this to be a temporary failure.

I've tested this approach by artificially making
sk_stream_alloc_skb() return NULL periodically. In that case,
epoll edge trigger waiters will hang indefinitely in epoll_wait()
without this patch.
Signed-off-by: NJason Baron <jbaron@akamai.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Vijay reported that a loop as simple as ...

  while true; do
    tc qdisc add dev foo root handle 1: prio
    tc filter add dev foo parent 1: u32 match u32 0 0  flowid 1
    tc qdisc del dev foo root
    rmmod cls_u32
  done

... will panic the kernel. Moreover, he bisected the change
apparently introducing it to 78fd1d0a ("netlink: Re-add
locking to netlink_lookup() and seq walker").

The removal of synchronize_net() from the netlink socket
triggering the qdisc to be removed, seems to have uncovered
an RCU resp. module reference count race from the tc API.
Given that RCU conversion was done after e341694e ("netlink:
Convert netlink_lookup() to use RCU protected hash table")
which added the synchronize_net() originally, occasion of
hitting the bug was less likely (not impossible though):

When qdiscs that i) support attaching classifiers and,
ii) have at least one of them attached, get deleted, they
invoke tcf_destroy_chain(), and thus call into ->destroy()
handler from a classifier module.

After RCU conversion, all classifier that have an internal
prio list, unlink them and initiate freeing via call_rcu()
deferral.

Meanhile, tcf_destroy() releases already reference to the
tp->ops->owner module before the queued RCU callback handler
has been invoked.

Subsequent rmmod on the classifier module is then not prevented
since all module references are already dropped.

By the time, the kernel invokes the RCU callback handler from
the module, that function address is then invalid.

One way to fix it would be to add an rcu_barrier() to
unregister_tcf_proto_ops() to wait for all pending call_rcu()s
to complete.

synchronize_rcu() is not appropriate as under heavy RCU
callback load, registered call_rcu()s could be deferred
longer than a grace period. In case we don't have any pending
call_rcu()s, the barrier is allowed to return immediately.

Since we came here via unregister_tcf_proto_ops(), there
are no users of a given classifier anymore. Further nested
call_rcu()s pointing into the module space are not being
done anywhere.

Only cls_bpf_delete_prog() may schedule a work item, to
unlock pages eventually, but that is not in the range/context
of cls_bpf anymore.

Fixes: 25d8c0d5 ("net: rcu-ify tcf_proto")
Fixes: 9888faef ("net: sched: cls_basic use RCU")
Reported-by: NVijay Subramanian <subramanian.vijay@gmail.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Cc: John Fastabend <john.r.fastabend@intel.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Thomas Graf <tgraf@suug.ch>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Tested-by: NVijay Subramanian <subramanian.vijay@gmail.com>
Acked-by: NAlexei Starovoitov <ast@plumgrid.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>