This patch uses a seqlock to ensure consistency between idst->dst and
idst->cookie.  It also makes dst freeing from fib tree to undergo a
rcu grace period.
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is a prep work to get dst freeing from fib tree undergo
a rcu grace period.

The following is a common paradigm:
if (ip6_del_rt(rt))
	dst_free(rt)

which means, if rt cannot be deleted from the fib tree, dst_free(rt) now.
1. We don't know the ip6_del_rt(rt) failure is because it
   was not managed by fib tree (e.g. DST_NOCACHE) or it had already been
   removed from the fib tree.
2. If rt had been managed by the fib tree, ip6_del_rt(rt) failure means
   dst_free(rt) has been called already.  A second
   dst_free(rt) is not always obviously safe.  The rt may have
   been destroyed already.
3. If rt is a DST_NOCACHE, dst_free(rt) should not be called.
4. It is a stopper to make dst freeing from fib tree undergo a
   rcu grace period.

This patch is to use a DST_NOCACHE flag to indicate a rt is
not managed by the fib tree.
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Problems in the current dst_entry cache in the ip6_tunnel:

1. ip6_tnl_dst_set is racy.  There is no lock to protect it:
   - One major problem is that the dst refcnt gets messed up. F.e.
     the same dst_cache can be released multiple times and then
     triggering the infamous dst refcnt < 0 warning message.
   - Another issue is the inconsistency between dst_cache and
     dst_cookie.

   It can be reproduced by adding and removing the ip6gre tunnel
   while running a super_netperf TCP_CRR test.

2. ip6_tnl_dst_get does not take the dst refcnt before returning
   the dst.

This patch:
1. Create a percpu dst_entry cache in ip6_tnl
2. Use a spinlock to protect the dst_cache operations
3. ip6_tnl_dst_get always takes the dst refcnt before returning
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is a prep work to fix the dst_entry refcnt bugs in
ip6_tunnel.

This patch rename:
1. ip6_tnl_dst_check() to ip6_tnl_dst_get() to better
   reflect that it will take a dst refcnt in the next patch.
2. ip6_tnl_dst_store() to ip6_tnl_dst_set() to have a more
   conventional name matching with ip6_tnl_dst_get().
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is a prep work to fix the dst_entry refcnt bugs in ip6_tunnel.

This patch refactors some common init codes used by both
ip6gre_tunnel_init and ip6gre_tap_init.
Signed-off-by: NMartin KaFai Lau <kafai@fb.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When NF_CONNTRACK is built-in, NF_DEFRAG_IPV6 is a module, and
OPENVSWITCH is built-in, the following build error would occur:

net/built-in.o: In function `ovs_ct_execute':
(.text+0x10f587): undefined reference to `nf_ct_frag6_gather'

Fixes: 7f8a436e ("openvswitch: Add conntrack action")
Reported-by: NJim Davis <jim.epost@gmail.com>
Signed-off-by: NJoe Stringer <joestringer@nicira.com>
Acked-by: NPravin B Shelar <pshelar@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

With the newly introduced helper functions the skb pulling is hidden in
the checksumming function - and undone before returning to the caller.

The IGMPv3 and MLDv2 report parsing functions in the bridge still
assumed that the skb is pointing to the beginning of the IGMP/MLD
message while it is now kept at the beginning of the IPv4/6 header,
breaking the message parsing and creating packet loss.

Fixing this by taking the offset between IP and IGMP/MLD header into
account, too.

Fixes: 9afd85c9 ("net: Export IGMP/MLD message validation code")
Reported-by: NTobias Powalowski <tobias.powalowski@googlemail.com>
Tested-by: NTobias Powalowski <tobias.powalowski@googlemail.com>
Signed-off-by: NLinus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Consider sctp module is unloaded and is being requested because an user
is creating a sctp socket.

During initialization, sctp will add the new protocol type and then
initialize pernet subsys:

        status = sctp_v4_protosw_init();
        if (status)
                goto err_protosw_init;

        status = sctp_v6_protosw_init();
        if (status)
                goto err_v6_protosw_init;

        status = register_pernet_subsys(&sctp_net_ops);

The problem is that after those calls to sctp_v{4,6}_protosw_init(), it
is possible for userspace to create SCTP sockets like if the module is
already fully loaded. If that happens, one of the possible effects is
that we will have readers for net->sctp.local_addr_list list earlier
than expected and sctp_net_init() does not take precautions while
dealing with that list, leading to a potential panic but not limited to
that, as sctp_sock_init() will copy a bunch of blank/partially
initialized values from net->sctp.

The race happens like this:

     CPU 0                           |  CPU 1
  socket()                           |
   __sock_create                     | socket()
    inet_create                      |  __sock_create
     list_for_each_entry_rcu(        |
        answer, &inetsw[sock->type], |
        list) {                      |   inet_create
      /* no hits */                  |
     if (unlikely(err)) {            |
      ...                            |
      request_module()               |
      /* socket creation is blocked  |
       * the module is fully loaded  |
       */                            |
       sctp_init                     |
        sctp_v4_protosw_init         |
         inet_register_protosw       |
          list_add_rcu(&p->list,     |
                       last_perm);   |
                                     |  list_for_each_entry_rcu(
                                     |     answer, &inetsw[sock->type],
        sctp_v6_protosw_init         |     list) {
                                     |     /* hit, so assumes protocol
                                     |      * is already loaded
                                     |      */
                                     |  /* socket creation continues
                                     |   * before netns is initialized
                                     |   */
        register_pernet_subsys       |

Simply inverting the initialization order between
register_pernet_subsys() and sctp_v4_protosw_init() is not possible
because register_pernet_subsys() will create a control sctp socket, so
the protocol must be already visible by then. Deferring the socket
creation to a work-queue is not good specially because we loose the
ability to handle its errors.

So, as suggested by Vlad, the fix is to split netns initialization in
two moments: defaults and control socket, so that the defaults are
already loaded by when we register the protocol, while control socket
initialization is kept at the same moment it is today.

Fixes: 4db67e80 ("sctp: Make the address lists per network namespace")
Signed-off-by: NVlad Yasevich <vyasevich@gmail.com>
Signed-off-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Instead of always emitting BPF_REG_X, let's emit BPF_REG_X only when the
source actually is BPF_X. This causes programs generated by the classic
converter to not be importable via bpf(), as the eBPF verifier checks that
the src_reg is correct or 0. While not a problem yet, this will be a
problem when BPF_PROG_DUMP lands, and we can potentially dump and re-import
programs generated by the converter.
Signed-off-by: NTycho Andersen <tycho.andersen@canonical.com>
CC: Alexei Starovoitov <ast@kernel.org>
CC: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Ken-ichirou reported that running netlink in mmap mode for receive in
combination with nlmon will throw a NULL pointer dereference in
__kfree_skb() on nlmon_xmit(), in my case I can also trigger an "unable
to handle kernel paging request". The problem is the skb_clone() in
__netlink_deliver_tap_skb() for skbs that are mmaped.

I.e. the cloned skb doesn't have a destructor, whereas the mmap netlink
skb has it pointed to netlink_skb_destructor(), set in the handler
netlink_ring_setup_skb(). There, skb->head is being set to NULL, so
that in such cases, __kfree_skb() doesn't perform a skb_release_data()
via skb_release_all(), where skb->head is possibly being freed through
kfree(head) into slab allocator, although netlink mmap skb->head points
to the mmap buffer. Similarly, the same has to be done also for large
netlink skbs where the data area is vmalloced. Therefore, as discussed,
make a copy for these rather rare cases for now. This fixes the issue
on my and Ken-ichirou's test-cases.

Reference: http://thread.gmane.org/gmane.linux.network/371129
Fixes: bcbde0d4 ("net: netlink: virtual tap device management")
Reported-by: NKen-ichirou MATSUZAWA <chamaken@gmail.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Tested-by: NKen-ichirou MATSUZAWA <chamaken@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Jana Iyengar found an interesting issue on CUBIC :

The epoch is only updated/reset initially and when experiencing losses.
The delta "t" of now - epoch_start can be arbitrary large after app idle
as well as the bic_target. Consequentially the slope (inverse of
ca->cnt) would be really large, and eventually ca->cnt would be
lower-bounded in the end to 2 to have delayed-ACK slow-start behavior.

This particularly shows up when slow_start_after_idle is disabled
as a dangerous cwnd inflation (1.5 x RTT) after few seconds of idle
time.

Jana initial fix was to reset epoch_start if app limited,
but Neal pointed out it would ask the CUBIC algorithm to recalculate the
curve so that we again start growing steeply upward from where cwnd is
now (as CUBIC does just after a loss). Ideally we'd want the cwnd growth
curve to be the same shape, just shifted later in time by the amount of
the idle period.
Reported-by: NJana Iyengar <jri@google.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NYuchung Cheng <ycheng@google.com>
Signed-off-by: NNeal Cardwell <ncardwell@google.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: Sangtae Ha <sangtae.ha@gmail.com>
Cc: Lawrence Brakmo <lawrence@brakmo.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Issuing a CC TX_START event on control frames like pure ACK
is a waste of time, as a CC should not care.

Following patch needs this change, as we want CUBIC to properly track
idle time at a low cost, with a single TX_START being generated.

Yuchung might slightly refine the condition triggering TX_START
on a followup patch.
Signed-off-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NYuchung Cheng <ycheng@google.com>
Cc: Jana Iyengar <jri@google.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: Sangtae Ha <sangtae.ha@gmail.com>
Cc: Lawrence Brakmo <lawrence@brakmo.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When netlink mmap on receive side is the consumer of nf queue data,
it can happen that in some edge cases, we write skb shared info into
the user space mmap buffer:

Assume a possible rx ring frame size of only 4096, and the network skb,
which is being zero-copied into the netlink skb, contains page frags
with an overall skb->len larger than the linear part of the netlink
skb.

skb_zerocopy(), which is generic and thus not aware of the fact that
shared info cannot be accessed for such skbs then tries to write and
fill frags, thus leaking kernel data/pointers and in some corner cases
possibly writing out of bounds of the mmap area (when filling the
last slot in the ring buffer this way).

I.e. the ring buffer slot is then of status NL_MMAP_STATUS_VALID, has
an advertised length larger than 4096, where the linear part is visible
at the slot beginning, and the leaked sizeof(struct skb_shared_info)
has been written to the beginning of the next slot (also corrupting
the struct nl_mmap_hdr slot header incl. status etc), since skb->end
points to skb->data + ring->frame_size - NL_MMAP_HDRLEN.

The fix adds and lets __netlink_alloc_skb() take the actual needed
linear room for the network skb + meta data into account. It's completely
irrelevant for non-mmaped netlink sockets, but in case mmap sockets
are used, it can be decided whether the available skb_tailroom() is
really large enough for the buffer, or whether it needs to internally
fallback to a normal alloc_skb().

>From nf queue side, the information whether the destination port is
an mmap RX ring is not really available without extra port-to-socket
lookup, thus it can only be determined in lower layers i.e. when
__netlink_alloc_skb() is called that checks internally for this. I
chose to add the extra ldiff parameter as mmap will then still work:
We have data_len and hlen in nfqnl_build_packet_message(), data_len
is the full length (capped at queue->copy_range) for skb_zerocopy()
and hlen some possible part of data_len that needs to be copied; the
rem_len variable indicates the needed remaining linear mmap space.

The only other workaround in nf queue internally would be after
allocation time by f.e. cap'ing the data_len to the skb_tailroom()
iff we deal with an mmap skb, but that would 1) expose the fact that
we use a mmap skb to upper layers, and 2) trim the skb where we
otherwise could just have moved the full skb into the normal receive
queue.

After the patch, in my test case the ring slot doesn't fit and therefore
shows NL_MMAP_STATUS_COPY, where a full skb carries all the data and
thus needs to be picked up via recv().

Fixes: 3ab1f683 ("nfnetlink: add support for memory mapped netlink")
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In case of netlink mmap, there can be situations where received frames
have to be placed into the normal receive queue. The ring buffer indicates
this through NL_MMAP_STATUS_COPY, so the user is asked to pick them up
via recvmsg(2) syscall, and to put the slot back to NL_MMAP_STATUS_UNUSED.

Commit 0ef70770 ("netlink: rx mmap: fix POLLIN condition") changed
polling, so that we walk in the worst case the whole ring through the
new netlink_has_valid_frame(), for example, when the ring would have no
NL_MMAP_STATUS_VALID, but at least one NL_MMAP_STATUS_COPY frame.

Since we do a datagram_poll() already earlier to pick up a mask that could
possibly contain POLLIN | POLLRDNORM already (due to NL_MMAP_STATUS_COPY),
we can skip checking the rx ring entirely.

In case the kernel is compiled with !CONFIG_NETLINK_MMAP, then all this is
irrelevant anyway as netlink_poll() is just defined as datagram_poll().
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv6/route.c:2946:3-8: WARNING: NULL check before freeing functions like kfree, debugfs_remove, debugfs_remove_recursive or usb_free_urb is not needed. Maybe consider reorganizing relevant code to avoid passing NULL values.

 NULL check before some freeing functions is not needed.

 Based on checkpatch warning
 "kfree(NULL) is safe this check is probably not required"
 and kfreeaddr.cocci by Julia Lawall.

Generated by: scripts/coccinelle/free/ifnullfree.cocci

CC: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: NFengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This switches IPv6 policy routing to use the shared
fib_default_rule_pref() function of IPv4 and DECnet. It is also used in
multicast routing for IPv4 as well as IPv6.

The motivation for this patch is a complaint about iproute2 behaving
inconsistent between IPv4 and IPv6 when adding policy rules: Formerly,
IPv6 rules were assigned a fixed priority of 0x3FFF whereas for IPv4 the
assigned priority value was decreased with each rule added.

Since then all users of the default_pref field have been converted to
assign the generic function fib_default_rule_pref(), fib_nl_newrule()
may just use it directly instead. Therefore get rid of the function
pointer altogether and make fib_default_rule_pref() static, as it's not
used outside fib_rules.c anymore.
Signed-off-by: NPhil Sutter <phil@nwl.cc>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Problem:
The ecmp route replace support for ipv6 in the kernel, deletes the
existing ecmp route too early, ie when it installs the first nexthop.
If there is an error in installing the subsequent nexthops, its too late
to recover the already deleted existing route leaving the fib
in an inconsistent state.

This patch reduces the possibility of this by doing the following:
a) Changes the existing multipath route add code to a two stage process:
  build rt6_infos + insert them
	ip6_route_add rt6_info creation code is moved into
	ip6_route_info_create.
b) This ensures that most errors are caught during building rt6_infos
  and we fail early
c) Separates multipath add and del code. Because add needs the special
  two stage mode in a) and delete essentially does not care.
d) In any event if the code fails during inserting a route again, a
  warning is printed (This should be unlikely)

Before the patch:
$ip -6 route show
3000:1000:1000:1000::2 via fe80::202:ff:fe00:b dev swp49s0 metric 1024
3000:1000:1000:1000::2 via fe80::202:ff:fe00:d dev swp49s1 metric 1024
3000:1000:1000:1000::2 via fe80::202:ff:fe00:f dev swp49s2 metric 1024

/* Try replacing the route with a duplicate nexthop */
$ip -6 route change 3000:1000:1000:1000::2/128 nexthop via
fe80::202:ff:fe00:b dev swp49s0 nexthop via fe80::202:ff:fe00:d dev
swp49s1 nexthop via fe80::202:ff:fe00:d dev swp49s1
RTNETLINK answers: File exists

$ip -6 route show
/* previously added ecmp route 3000:1000:1000:1000::2 dissappears from
 * kernel */

After the patch:
$ip -6 route show
3000:1000:1000:1000::2 via fe80::202:ff:fe00:b dev swp49s0 metric 1024
3000:1000:1000:1000::2 via fe80::202:ff:fe00:d dev swp49s1 metric 1024
3000:1000:1000:1000::2 via fe80::202:ff:fe00:f dev swp49s2 metric 1024

/* Try replacing the route with a duplicate nexthop */
$ip -6 route change 3000:1000:1000:1000::2/128 nexthop via
fe80::202:ff:fe00:b dev swp49s0 nexthop via fe80::202:ff:fe00:d dev
swp49s1 nexthop via fe80::202:ff:fe00:d dev swp49s1
RTNETLINK answers: File exists

$ip -6 route show
3000:1000:1000:1000::2 via fe80::202:ff:fe00:b dev swp49s0 metric 1024
3000:1000:1000:1000::2 via fe80::202:ff:fe00:d dev swp49s1 metric 1024
3000:1000:1000:1000::2 via fe80::202:ff:fe00:f dev swp49s2 metric 1024

Fixes: 27596472 ("ipv6: fix ECMP route replacement")
Signed-off-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Reviewed-by: NNikolay Aleksandrov <nikolay@cumulusnetworks.com>
Acked-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There was no verification that an underlying transport exists when creating
a connection, this would cause dereferencing a NULL ptr.

It might happen on sockets that weren't properly bound before attempting to
send a message, which will cause a NULL ptr deref:

[135546.047719] kasan: GPF could be caused by NULL-ptr deref or user memory accessgeneral protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC KASAN
[135546.051270] Modules linked in:
[135546.051781] CPU: 4 PID: 15650 Comm: trinity-c4 Not tainted 4.2.0-next-20150902-sasha-00041-gbaa1222-dirty #2527
[135546.053217] task: ffff8800835bc000 ti: ffff8800bc708000 task.ti: ffff8800bc708000
[135546.054291] RIP: __rds_conn_create (net/rds/connection.c:194)
[135546.055666] RSP: 0018:ffff8800bc70fab0  EFLAGS: 00010202
[135546.056457] RAX: dffffc0000000000 RBX: 0000000000000f2c RCX: ffff8800835bc000
[135546.057494] RDX: 0000000000000007 RSI: ffff8800835bccd8 RDI: 0000000000000038
[135546.058530] RBP: ffff8800bc70fb18 R08: 0000000000000001 R09: 0000000000000000
[135546.059556] R10: ffffed014d7a3a23 R11: ffffed014d7a3a21 R12: 0000000000000000
[135546.060614] R13: 0000000000000001 R14: ffff8801ec3d0000 R15: 0000000000000000
[135546.061668] FS:  00007faad4ffb700(0000) GS:ffff880252000000(0000) knlGS:0000000000000000
[135546.062836] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[135546.063682] CR2: 000000000000846a CR3: 000000009d137000 CR4: 00000000000006a0
[135546.064723] Stack:
[135546.065048]  ffffffffafe2055c ffffffffafe23fc1 ffffed00493097bf ffff8801ec3d0008
[135546.066247]  0000000000000000 00000000000000d0 0000000000000000 ac194a24c0586342
[135546.067438]  1ffff100178e1f78 ffff880320581b00 ffff8800bc70fdd0 ffff880320581b00
[135546.068629] Call Trace:
[135546.069028] ? __rds_conn_create (include/linux/rcupdate.h:856 net/rds/connection.c:134)
[135546.069989] ? rds_message_copy_from_user (net/rds/message.c:298)
[135546.071021] rds_conn_create_outgoing (net/rds/connection.c:278)
[135546.071981] rds_sendmsg (net/rds/send.c:1058)
[135546.072858] ? perf_trace_lock (include/trace/events/lock.h:38)
[135546.073744] ? lockdep_init (kernel/locking/lockdep.c:3298)
[135546.074577] ? rds_send_drop_to (net/rds/send.c:976)
[135546.075508] ? __might_fault (./arch/x86/include/asm/current.h:14 mm/memory.c:3795)
[135546.076349] ? __might_fault (mm/memory.c:3795)
[135546.077179] ? rds_send_drop_to (net/rds/send.c:976)
[135546.078114] sock_sendmsg (net/socket.c:611 net/socket.c:620)
[135546.078856] SYSC_sendto (net/socket.c:1657)
[135546.079596] ? SYSC_connect (net/socket.c:1628)
[135546.080510] ? trace_dump_stack (kernel/trace/trace.c:1926)
[135546.081397] ? ring_buffer_unlock_commit (kernel/trace/ring_buffer.c:2479 kernel/trace/ring_buffer.c:2558 kernel/trace/ring_buffer.c:2674)
[135546.082390] ? trace_buffer_unlock_commit (kernel/trace/trace.c:1749)
[135546.083410] ? trace_event_raw_event_sys_enter (include/trace/events/syscalls.h:16)
[135546.084481] ? do_audit_syscall_entry (include/trace/events/syscalls.h:16)
[135546.085438] ? trace_buffer_unlock_commit (kernel/trace/trace.c:1749)
[135546.085515] rds_ib_laddr_check(): addr 36.74.25.172 ret -99 node type -1
Acked-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: NSasha Levin <sasha.levin@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If an attempt to wake up users of broadcast link is made when there is
no enough place in send queue than it may hang up inside the
tipc_sk_rcv() function since the loop breaks only after the wake up
queue becomes empty. This can lead to complete CPU stall with the
following message generated by RCU:

INFO: rcu_sched self-detected stall on CPU { 0}  (t=2101 jiffies
					g=54225 c=54224 q=11465)
Task dump for CPU 0:
tpch            R  running task        0 39949  39948 0x0000000a
 ffffffff818536c0 ffff88181fa037a0 ffffffff8106a4be 0000000000000000
 ffffffff818536c0 ffff88181fa037c0 ffffffff8106d8a8 ffff88181fa03800
 0000000000000001 ffff88181fa037f0 ffffffff81094a50 ffff88181fa15680
Call Trace:
 <IRQ>  [<ffffffff8106a4be>] sched_show_task+0xae/0x120
 [<ffffffff8106d8a8>] dump_cpu_task+0x38/0x40
 [<ffffffff81094a50>] rcu_dump_cpu_stacks+0x90/0xd0
 [<ffffffff81097c3b>] rcu_check_callbacks+0x3eb/0x6e0
 [<ffffffff8106e53f>] ? account_system_time+0x7f/0x170
 [<ffffffff81099e64>] update_process_times+0x34/0x60
 [<ffffffff810a84d1>] tick_sched_handle.isra.18+0x31/0x40
 [<ffffffff810a851c>] tick_sched_timer+0x3c/0x70
 [<ffffffff8109a43d>] __run_hrtimer.isra.34+0x3d/0xc0
 [<ffffffff8109aa95>] hrtimer_interrupt+0xc5/0x1e0
 [<ffffffff81030d52>] ? native_smp_send_reschedule+0x42/0x60
 [<ffffffff81032f04>] local_apic_timer_interrupt+0x34/0x60
 [<ffffffff810335bc>] smp_apic_timer_interrupt+0x3c/0x60
 [<ffffffff8165a3fb>] apic_timer_interrupt+0x6b/0x70
 [<ffffffff81659129>] ? _raw_spin_unlock_irqrestore+0x9/0x10
 [<ffffffff8107eb9f>] __wake_up_sync_key+0x4f/0x60
 [<ffffffffa313ddd1>] tipc_write_space+0x31/0x40 [tipc]
 [<ffffffffa313dadf>] filter_rcv+0x31f/0x520 [tipc]
 [<ffffffffa313d699>] ? tipc_sk_lookup+0xc9/0x110 [tipc]
 [<ffffffff81659259>] ? _raw_spin_lock_bh+0x19/0x30
 [<ffffffffa314122c>] tipc_sk_rcv+0x2dc/0x3e0 [tipc]
 [<ffffffffa312e7ff>] tipc_bclink_wakeup_users+0x2f/0x40 [tipc]
 [<ffffffffa313ce26>] tipc_node_unlock+0x186/0x190 [tipc]
 [<ffffffff81597c1c>] ? kfree_skb+0x2c/0x40
 [<ffffffffa313475c>] tipc_rcv+0x2ac/0x8c0 [tipc]
 [<ffffffffa312ff58>] tipc_l2_rcv_msg+0x38/0x50 [tipc]
 [<ffffffff815a76d3>] __netif_receive_skb_core+0x5a3/0x950
 [<ffffffff815a98d3>] __netif_receive_skb+0x13/0x60
 [<ffffffff815a993e>] netif_receive_skb_internal+0x1e/0x90
 [<ffffffff815aa138>] napi_gro_receive+0x78/0xa0
 [<ffffffffa07f93f4>] tg3_poll_work+0xc54/0xf40 [tg3]
 [<ffffffff81597c8c>] ? consume_skb+0x2c/0x40
 [<ffffffffa07f9721>] tg3_poll_msix+0x41/0x160 [tg3]
 [<ffffffff815ab0f2>] net_rx_action+0xe2/0x290
 [<ffffffff8104b92a>] __do_softirq+0xda/0x1f0
 [<ffffffff8104bc26>] irq_exit+0x76/0xa0
 [<ffffffff81004355>] do_IRQ+0x55/0xf0
 [<ffffffff8165a12b>] common_interrupt+0x6b/0x6b
 <EOI>

The issue occurs only when tipc_sk_rcv() is used to wake up postponed
senders:

	tipc_bclink_wakeup_users()
		// wakeupq - is a queue which consists of special
		// 		 messages with SOCK_WAKEUP type.
		tipc_sk_rcv(wakeupq)
			...
			while (skb_queue_len(inputq)) {
				filter_rcv(skb)
					// Here the type of message is checked
					// and if it is SOCK_WAKEUP then
					// it tries to wake up a sender.
					tipc_write_space(sk)
						wake_up_interruptible_sync_poll()
			}

After the sender thread is woke up it can gather control and perform
an attempt to send a message. But if there is no enough place in send
queue it will call link_schedule_user() function which puts a message
of type SOCK_WAKEUP to the wakeup queue and put the sender to sleep.
Thus the size of the queue actually is not changed and the while()
loop never exits.

The approach I proposed is to wake up only senders for which there is
enough place in send queue so the described issue can't occur.
Moreover the same approach is already used to wake up senders on
unicast links.

I have got into the issue on our product code but to reproduce the
issue I changed a benchmark test application (from
tipcutils/demos/benchmark) to perform the following scenario:
	1. Run 64 instances of test application (nodes). It can be done
	   on the one physical machine.
	2. Each application connects to all other using TIPC sockets in
	   RDM mode.
	3. When setup is done all nodes start simultaneously send
	   broadcast messages.
	4. Everything hangs up.

The issue is reproducible only when a congestion on broadcast link
occurs. For example, when there are only 8 nodes it works fine since
congestion doesn't occur. Send queue limit is 40 in my case (I use a
critical importance level) and when 64 nodes send a message at the
same moment a congestion occurs every time.
Signed-off-by: NDmitry S Kolmakov <kolmakov.dmitriy@huawei.com>
Reviewed-by: NJon Maloy <jon.maloy@ericsson.com>
Acked-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove the unnecessary switchdev.h include from br_netlink.c.
Signed-off-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since __vlan_del can return an error code, change its inner function
__vlan_vid_del to return an eventual error from switchdev_port_obj_del.
Signed-off-by: NVivien Didelot <vivien.didelot@savoirfairelinux.com>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There's no particular desire to have conntrack action support in Open
vSwitch as an independently configurable bit, rather just to ensure
there is not a hard dependency. This exposed option doesn't accurately
reflect the conntrack dependency when enabled, so simplify this by
removing the option. Compile the support if NF_CONNTRACK is enabled.

Fixes: 7f8a436e ("openvswitch: Add conntrack action")
Signed-off-by: NJoe Stringer <joestringer@nicira.com>
Acked-by: NPravin B Shelar <pshelar@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Only return a conn if the rds_conn_net(conn) matches the struct
net passed to rds_conn_lookup().

Fixes: 467fa153 ("RDS-TCP: Support multiple RDS-TCP listen endpoints,
       one per netns.")
Signed-off-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Acked-by: NSantosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

switchdev_port_fdb_dump is used as .ndo_fdb_dump. Its return value is
idx, so we cannot return errval.

Fixes: 45d4122c ("switchdev: add support for fdb add/del/dump via switchdev_port_obj ops.")
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Acked-by: NSridhar Samudrala <sridhar.samudrala@intel.com>
Acked-by: Scott Feldman<sfeldma@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the IPv6 multicast routing code the mrt_lock was not being released
correctly in the MFC iterator, as a result adding or deleting a MIF would
cause a hang because the mrt_lock could not be acquired.

This fix is a copy of the code for the IPv4 case and ensures that the lock
is released correctly.
Signed-off-by: NRichard Laing <richard.laing@alliedtelesis.co.nz>
Acked-by: NCong Wang <cwang@twopensource.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

userfaultfd needs to wake all waitqueues (pass 0 as nr parameter), instead
of the current hardcoded 1 (that would wake just the first waitqueue in
the head list).
Signed-off-by: NAndrea Arcangeli <aarcange@redhat.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Cc: Sanidhya Kashyap <sanidhya.gatech@gmail.com>
Cc: zhang.zhanghailiang@huawei.com
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: Peter Feiner <pfeiner@google.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Huangpeng (Peter)" <peter.huangpeng@huawei.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Many file systems that implement the show_options hook fail to correctly
escape their output which could lead to unescaped characters (e.g.  new
lines) leaking into /proc/mounts and /proc/[pid]/mountinfo files.  This
could lead to confusion, spoofed entries (resulting in things like
systemd issuing false d-bus "mount" notifications), and who knows what
else.  This looks like it would only be the root user stepping on
themselves, but it's possible weird things could happen in containers or
in other situations with delegated mount privileges.

Here's an example using overlay with setuid fusermount trusting the
contents of /proc/mounts (via the /etc/mtab symlink).  Imagine the use
of "sudo" is something more sneaky:

  $ BASE="ovl"
  $ MNT="$BASE/mnt"
  $ LOW="$BASE/lower"
  $ UP="$BASE/upper"
  $ WORK="$BASE/work/ 0 0
  none /proc fuse.pwn user_id=1000"
  $ mkdir -p "$LOW" "$UP" "$WORK"
  $ sudo mount -t overlay -o "lowerdir=$LOW,upperdir=$UP,workdir=$WORK" none /mnt
  $ cat /proc/mounts
  none /root/ovl/mnt overlay rw,relatime,lowerdir=ovl/lower,upperdir=ovl/upper,workdir=ovl/work/ 0 0
  none /proc fuse.pwn user_id=1000 0 0
  $ fusermount -u /proc
  $ cat /proc/mounts
  cat: /proc/mounts: No such file or directory

This fixes the problem by adding new seq_show_option and
seq_show_option_n helpers, and updating the vulnerable show_option
handlers to use them as needed.  Some, like SELinux, need to be open
coded due to unusual existing escape mechanisms.

[akpm@linux-foundation.org: add lost chunk, per Kees]
[keescook@chromium.org: seq_show_option should be using const parameters]
Signed-off-by: NKees Cook <keescook@chromium.org>
Acked-by: NSerge Hallyn <serge.hallyn@canonical.com>
Acked-by: NJan Kara <jack@suse.com>
Acked-by: NPaul Moore <paul@paul-moore.com>
Cc: J. R. Okajima <hooanon05g@gmail.com>
Signed-off-by: NKees Cook <keescook@chromium.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When beacon filtering is enabled the mac80211 software implementation
for RSSI CQM cannot work as beacons will not be available. Rather than
accepting such a configuration without proper effect, reject it.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Currently if 80MHz channels are not allowed for use, the VHT IE is not
included in the probe request for an AP. This is not good enough if the
AP is configured with the wrong regulatory and supports VHT even where
prohibited or in TDLS scenarios.
Mark the ifmgd with the DISABLE_VHT flag for the misbehaving-AP case, and
unset VHT support from the peer-station entry for the TDLS case.
Signed-off-by: NArik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

restore_regulatory_settings() should restore alpha2
as computed in restore_alpha2(), not raw user_alpha2 to
behave as described in the comment just above that code.

This fixes endless loop of calling CRDA for "00" and "97"
countries after resume from suspend on my laptop.

Looks like others had the same problem, too:
http://ath9k-devel.ath9k.narkive.com/knY5W6St/ath9k-and-crda-messages-in-logs
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/899335
https://forum.porteus.org/viewtopic.php?t=4975&p=36436
https://forums.opensuse.org/showthread.php/483356-Authentication-Regulatory-Domain-issues-ath5k-12-2Signed-off-by: NMaciej Szmigiero <mail@maciej.szmigiero.name>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

When switching the state of all RFKill switches of type all we need to
replicate the RFKILL_TYPE_ALL global state to all the other types global
state, so it is used to initialize persistent RFKill switches on
register.
Signed-off-by: NJoão Paulo Rechi Vita <jprvita@endlessm.com>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

HT TDLS traffic should be protected in a non-HT BSS to avoid
collisions. Therefore, when TDLS peers join/leave, check if
protection is (now) needed and set the ht_operation_mode of
the virtual interface according to the HT capabilities of the
TDLS peer(s).

This works because a non-HT BSS connection never sets (or
otherwise uses) the ht_operation_mode; it just means that
drivers must be aware that this field applies to all HT
traffic for this virtual interface, not just the traffic
within the BSS. Document that.
Signed-off-by: NAvri Altman <avri.altman@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The rate_control_cap_mask() function takes a parameter mcs_mask, which
GCC will take to be u8 * even though it was declared with a fixed size.
This causes the following warning:

	net/mac80211/rate.c: In function 'rate_control_cap_mask':
	net/mac80211/rate.c:719:25: warning: 'sizeof' on array function parameter 'mcs_mask' will return size of 'u8 * {aka unsigned char *}' [-Wsizeof-array-argument]
	   for (i = 0; i < sizeof(mcs_mask); i++)
	                         ^
	net/mac80211/rate.c:684:10: note: declared here
	       u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN],
	          ^

This can be easily fixed by using the IEEE80211_HT_MCS_MASK_LEN directly
within the loop condition.
Signed-off-by: NThierry Reding <treding@nvidia.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Commit 0ca50d12 added a restriction that the address must belong to
the output interface, so that sctp will use the right interface even
when using secondary addresses.

But it breaks IPVS setups, on which people is used to attach VIP
addresses to loopback interface on real servers. It's preferred to
attach to the interface actually in use, but it's a very common setup
and that used to work.

This patch then saves the first routing good result, even if it would be
going out through an interface that doesn't have that address. If no
better hit found, it's then used. This effectively restores the original
behavior if no better interface could be found.

Fixes: 0ca50d12 ("sctp: fix src address selection if using secondary addresses")
Signed-off-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 0ca50d12 failed to release the reference to dst entries that
it decided to skip.

Fixes: 0ca50d12 ("sctp: fix src address selection if using secondary addresses")
Signed-off-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fengguang reported, that some randconfig generated the following linker
issue with nf_ct_zone_dflt object involved:

  [...]
  CC      init/version.o
  LD      init/built-in.o
  net/built-in.o: In function `ipv4_conntrack_defrag':
  nf_defrag_ipv4.c:(.text+0x93e95): undefined reference to `nf_ct_zone_dflt'
  net/built-in.o: In function `ipv6_defrag':
  nf_defrag_ipv6_hooks.c:(.text+0xe3ffe): undefined reference to `nf_ct_zone_dflt'
  make: *** [vmlinux] Error 1

Given that configurations exist where we have a built-in part, which is
accessing nf_ct_zone_dflt such as the two handlers nf_ct_defrag_user()
and nf_ct6_defrag_user(), and a part that configures nf_conntrack as a
module, we must move nf_ct_zone_dflt into a fixed, guaranteed built-in
area when netfilter is configured in general.

Therefore, split the more generic parts into a common header under
include/linux/netfilter/ and move nf_ct_zone_dflt into the built-in
section that already holds parts related to CONFIG_NF_CONNTRACK in the
netfilter core. This fixes the issue on my side.

Fixes: 308ac914 ("netfilter: nf_conntrack: push zone object into functions")
Reported-by: NFengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

While testing various Kconfig options on another issue, I found that
the following one triggers as well on allmodconfig and nf_conntrack
disabled:

  net/ipv4/netfilter/nf_dup_ipv4.c: In function ‘nf_dup_ipv4’:
  net/ipv4/netfilter/nf_dup_ipv4.c:72:20: error: ‘nf_skb_duplicated’ undeclared (first use in this function)
    if (this_cpu_read(nf_skb_duplicated))
  [...]
  net/ipv6/netfilter/nf_dup_ipv6.c: In function ‘nf_dup_ipv6’:
  net/ipv6/netfilter/nf_dup_ipv6.c:66:20: error: ‘nf_skb_duplicated’ undeclared (first use in this function)
    if (this_cpu_read(nf_skb_duplicated))

Fix it by including directly the header where it is defined.

Fixes: bbde9fc1 ("netfilter: factor out packet duplication for IPv4/IPv6")
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We previously register IPPROTO_ROUTING offload under inet6_add_offload(),
but in error path, we try to unregister it with inet_del_offload(). This
doesn't seem correct, it should actually be inet6_del_offload(), also
ipv6_exthdrs_offload_exit() from that commit seems rather incorrect (it
also uses rthdr_offload twice), but it got removed entirely later on.

Fixes: 3336288a ("ipv6: Switch to using new offload infrastructure.")
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

diag socket's sock_diag_put_filterinfo() dumps classic BPF programs
upon request to user space (ss -0 -b). However, native eBPF programs
attached to sockets (SO_ATTACH_BPF) cannot be dumped with this method:

Their orig_prog is always NULL. However, sock_diag_put_filterinfo()
unconditionally tries to access its filter length resp. wants to copy
the filter insns from there. Internal cBPF to eBPF transformations
attached to sockets don't have this issue, as orig_prog state is kept.

It's currently only used by packet sockets. If we would want to add
native eBPF support in the future, this needs to be done through
a different attribute than PACKET_DIAG_FILTER to not confuse possible
user space disassemblers that work on diag data.

Fixes: 89aa0758 ("net: sock: allow eBPF programs to be attached to sockets")
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: NAlexei Starovoitov <ast@plumgrid.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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