selinux: correctly label /proc inodes in use before the policy is loaded

commit f64410ec665479d7b4b77b7519e814253ed0f686 upstream.

This patch is based on an earlier patch by Eric Paris, he describes
the problem below:

  "If an inode is accessed before policy load it will get placed on a
   list of inodes to be initialized after policy load.  After policy
   load we call inode_doinit() which calls inode_doinit_with_dentry()
   on all inodes accessed before policy load.  In the case of inodes
   in procfs that means we'll end up at the bottom where it does:

     /* Default to the fs superblock SID. */
     isec->sid = sbsec->sid;

     if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
             if (opt_dentry) {
                     isec->sclass = inode_mode_to_security_class(...)
                     rc = selinux_proc_get_sid(opt_dentry,
                                               isec->sclass,
                                               &sid);
                     if (rc)
                             goto out_unlock;
                     isec->sid = sid;
             }
     }

   Since opt_dentry is null, we'll never call selinux_proc_get_sid()
   and will leave the inode labeled with the label on the superblock.
   I believe a fix would be to mimic the behavior of xattrs.  Look
   for an alias of the inode.  If it can't be found, just leave the
   inode uninitialized (and pick it up later) if it can be found, we
   should be able to call selinux_proc_get_sid() ..."

On a system exhibiting this problem, you will notice a lot of files in
/proc with the generic "proc_t" type (at least the ones that were
accessed early in the boot), for example:

   # ls -Z /proc/sys/kernel/shmmax | awk '{ print $4 " " $5 }'
   system_u:object_r:proc_t:s0 /proc/sys/kernel/shmmax

However, with this patch in place we see the expected result:

   # ls -Z /proc/sys/kernel/shmmax | awk '{ print $4 " " $5 }'
   system_u:object_r:sysctl_kernel_t:s0 /proc/sys/kernel/shmmax

Cc: Eric Paris <eparis@redhat.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
powernow-k6: disable cache when changing frequency

commit e20e1d0ac02308e2211306fc67abcd0b2668fb8b upstream.

I found out that a system with k6-3+ processor is unstable during network
server load. The system locks up or the network card stops receiving. The
reason for the instability is the CPU frequency scaling.

During frequency transition the processor is in "EPM Stop Grant" state.
The documentation says that the processor doesn't respond to inquiry
requests in this state. Consequently, coherency of processor caches and
bus master devices is not maintained, causing the system instability.

This patch flushes the cache during frequency transition. It fixes the
instability.

Other minor changes:
* u64 invalue changed to unsigned long because the variable is 32-bit
* move the logic to set the multiplier to a separate function
  powernow_k6_set_cpu_multiplier
* preserve lower 5 bits of the powernow port instead of 4 (the voltage
  field has 5 bits)
* mask interrupts when reading the multiplier, so that the port is not
  open during other activity (running other kernel code with the port open
  shouldn't cause any misbehavior, but we should better be safe and keep
  the port closed)

This patch should be backported to all stable kernels. If it doesn't
apply cleanly, change it, or ask me to change it.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
powernow-k6: correctly initialize default parameters

commit d82b922a4acc1781d368aceac2f9da43b038cab2 upstream.

The powernow-k6 driver used to read the initial multiplier from the
powernow register. However, there is a problem with this:

* If there was a frequency transition before, the multiplier read from the
  register corresponds to the current multiplier.
* If there was no frequency transition since reset, the field in the
  register always reads as zero, regardless of the current multiplier that
  is set using switches on the mainboard and that the CPU is running at.

The zero value corresponds to multiplier 4.5, so as a consequence, the
powernow-k6 driver always assumes multiplier 4.5.

For example, if we have 550MHz CPU with bus frequency 100MHz and
multiplier 5.5, the powernow-k6 driver thinks that the multiplier is 4.5
and bus frequency is 122MHz. The powernow-k6 driver then sets the
multiplier to 4.5, underclocking the CPU to 450MHz, but reports the
current frequency as 550MHz.

There is no reliable way how to read the initial multiplier. I modified
the driver so that it contains a table of known frequencies (based on
parameters of existing CPUs and some common overclocking schemes) and sets
the multiplier according to the frequency. If the frequency is unknown
(because of unusual overclocking or underclocking), the user must supply
the bus speed and maximum multiplier as module parameters.

This patch should be backported to all stable kernels. If it doesn't
apply cleanly, change it, or ask me to change it.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
powernow-k6: reorder frequencies

commit 22c73795b101597051924556dce019385a1e2fa0 upstream.

This patch reorders reported frequencies from the highest to the lowest,
just like in other frequency drivers.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kbuild: fix make headers_install when path is too long

commit c0ff68f1611d6855a06d672989ad5cfea160a4eb upstream.

If headers_install is executed from a deep/long directory structure, the
shell's maximum argument length can be execeeded, which breaks the operation
with:

| make[2]: execvp: /bin/sh: Argument list too long
| make[2]: ***

Instead of passing each files name with the entire path, I give only the file
name without the source path and give this path as a new argument to
headers_install.pl.

Because there is three possible paths, I have tree input-files list, one per
path.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Tested-by: Bruce Ashfield <bruce.ashfield@windriver.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
Cc: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net: fix for a race condition in the inet frag code

[ Upstream commit 24b9bf43e93e0edd89072da51cf1fab95fc69dec ]

I stumbled upon this very serious bug while hunting for another one,
it's a very subtle race condition between inet_frag_evictor,
inet_frag_intern and the IPv4/6 frag_queue and expire functions
(basically the users of inet_frag_kill/inet_frag_put).

What happens is that after a fragment has been added to the hash chain
but before it's been added to the lru_list (inet_frag_lru_add) in
inet_frag_intern, it may get deleted (either by an expired timer if
the system load is high or the timer sufficiently low, or by the
fraq_queue function for different reasons) before it's added to the
lru_list, then after it gets added it's a matter of time for the
evictor to get to a piece of memory which has been freed leading to a
number of different bugs depending on what's left there.

I've been able to trigger this on both IPv4 and IPv6 (which is normal
as the frag code is the same), but it's been much more difficult to
trigger on IPv4 due to the protocol differences about how fragments
are treated.

The setup I used to reproduce this is: 2 machines with 4 x 10G bonded
in a RR bond, so the same flow can be seen on multiple cards at the
same time. Then I used multiple instances of ping/ping6 to generate
fragmented packets and flood the machines with them while running
other processes to load the attacked machine.

*It is very important to have the _same flow_ coming in on multiple CPUs
concurrently. Usually the attacked machine would die in less than 30
minutes, if configured properly to have many evictor calls and timeouts
it could happen in 10 minutes or so.

An important point to make is that any caller (frag_queue or timer) of
inet_frag_kill will remove both the timer refcount and the
original/guarding refcount thus removing everything that's keeping the
frag from being freed at the next inet_frag_put.  All of this could
happen before the frag was ever added to the LRU list, then it gets
added and the evictor uses a freed fragment.

An example for IPv6 would be if a fragment is being added and is at
the stage of being inserted in the hash after the hash lock is
released, but before inet_frag_lru_add executes (or is able to obtain
the lru lock) another overlapping fragment for the same flow arrives
at a different CPU which finds it in the hash, but since it's
overlapping it drops it invoking inet_frag_kill and thus removing all
guarding refcounts, and afterwards freeing it by invoking
inet_frag_put which removes the last refcount added previously by
inet_frag_find, then inet_frag_lru_add gets executed by
inet_frag_intern and we have a freed fragment in the lru_list.

The fix is simple, just move the lru_add under the hash chain locked
region so when a removing function is called it'll have to wait for
the fragment to be added to the lru_list, and then it'll remove it (it
works because the hash chain removal is done before the lru_list one
and there's no window between the two list adds when the frag can get
dropped). With this fix applied I couldn't kill the same machine in 24
hours with the same setup.

Fixes: 3ef0eb0db4bf ("net: frag, move LRU list maintenance outside of
rwlock")

CC: Florian Westphal <fw@strlen.de>
CC: Jesper Dangaard Brouer <brouer@redhat.com>
CC: David S. Miller <davem@davemloft.net>

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net: sctp: fix skb leakage in COOKIE ECHO path of chunk->auth_chunk

[ Upstream commit c485658bae87faccd7aed540fd2ca3ab37992310 ]

While working on ec0223ec48a9 ("net: sctp: fix sctp_sf_do_5_1D_ce to
verify if we/peer is AUTH capable"), we noticed that there's a skb
memory leakage in the error path.

Running the same reproducer as in ec0223ec48a9 and by unconditionally
jumping to the error label (to simulate an error condition) in
sctp_sf_do_5_1D_ce() receive path lets kmemleak detector bark about
the unfreed chunk->auth_chunk skb clone:

Unreferenced object 0xffff8800b8f3a000 (size 256):
  comm "softirq", pid 0, jiffies 4294769856 (age 110.757s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    89 ab 75 5e d4 01 58 13 00 00 00 00 00 00 00 00  ..u^..X.........
  backtrace:
    [<ffffffff816660be>] kmemleak_alloc+0x4e/0xb0
    [<ffffffff8119f328>] kmem_cache_alloc+0xc8/0x210
    [<ffffffff81566929>] skb_clone+0x49/0xb0
    [<ffffffffa0467459>] sctp_endpoint_bh_rcv+0x1d9/0x230 [sctp]
    [<ffffffffa046fdbc>] sctp_inq_push+0x4c/0x70 [sctp]
    [<ffffffffa047e8de>] sctp_rcv+0x82e/0x9a0 [sctp]
    [<ffffffff815abd38>] ip_local_deliver_finish+0xa8/0x210
    [<ffffffff815a64af>] nf_reinject+0xbf/0x180
    [<ffffffffa04b4762>] nfqnl_recv_verdict+0x1d2/0x2b0 [nfnetlink_queue]
    [<ffffffffa04aa40b>] nfnetlink_rcv_msg+0x14b/0x250 [nfnetlink]
    [<ffffffff815a3269>] netlink_rcv_skb+0xa9/0xc0
    [<ffffffffa04aa7cf>] nfnetlink_rcv+0x23f/0x408 [nfnetlink]
    [<ffffffff815a2bd8>] netlink_unicast+0x168/0x250
    [<ffffffff815a2fa1>] netlink_sendmsg+0x2e1/0x3f0
    [<ffffffff8155cc6b>] sock_sendmsg+0x8b/0xc0
    [<ffffffff8155d449>] ___sys_sendmsg+0x369/0x380

What happens is that commit bbd0d59809f9 clones the skb containing
the AUTH chunk in sctp_endpoint_bh_rcv() when having the edge case
that an endpoint requires COOKIE-ECHO chunks to be authenticated:

  ---------- INIT[RANDOM; CHUNKS; HMAC-ALGO] ---------->
  <------- INIT-ACK[RANDOM; CHUNKS; HMAC-ALGO] ---------
  ------------------ AUTH; COOKIE-ECHO ---------------->
  <-------------------- COOKIE-ACK ---------------------

When we enter sctp_sf_do_5_1D_ce() and before we actually get to
the point where we process (and subsequently free) a non-NULL
chunk->auth_chunk, we could hit the "goto nomem_init" path from
an error condition and thus leave the cloned skb around w/o
freeing it.

The fix is to centrally free such clones in sctp_chunk_destroy()
handler that is invoked from sctp_chunk_free() after all refs have
dropped; and also move both kfree_skb(chunk->auth_chunk) there,
so that chunk->auth_chunk is either NULL (since sctp_chunkify()
allocs new chunks through kmem_cache_zalloc()) or non-NULL with
a valid skb pointer. chunk->skb and chunk->auth_chunk are the
only skbs in the sctp_chunk structure that need to be handeled.

While at it, we should use consume_skb() for both. It is the same
as dev_kfree_skb() but more appropriately named as we are not
a device but a protocol. Also, this effectively replaces the
kfree_skb() from both invocations into consume_skb(). Functions
are the same only that kfree_skb() assumes that the frame was
being dropped after a failure (e.g. for tools like drop monitor),
usage of consume_skb() seems more appropriate in function
sctp_chunk_destroy() though.

Fixes: bbd0d59809f9 ("[SCTP]: Implement the receive and verification of AUTH chunk")
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Vlad Yasevich <yasevich@gmail.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
bridge: multicast: add sanity check for query source addresses

[ Upstream commit 6565b9eeef194afbb3beec80d6dd2447f4091f8c ]

MLD queries are supposed to have an IPv6 link-local source address
according to RFC2710, section 4 and RFC3810, section 5.1.14. This patch
adds a sanity check to ignore such broken MLD queries.

Without this check, such malformed MLD queries can result in a
denial of service: The queries are ignored by any MLD listener
therefore they will not respond with an MLD report. However,
without this patch these malformed MLD queries would enable the
snooping part in the bridge code, potentially shutting down the
according ports towards these hosts for multicast traffic as the
bridge did not learn about these listeners.

Reported-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: Linus Lüssing <linus.luessing@web.de>
Reviewed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
inet: frag: make sure forced eviction removes all frags

[ Upstream commit e588e2f286ed7da011ed357c24c5b9a554e26595 ]

Quoting Alexander Aring:
  While fragmentation and unloading of 6lowpan module I got this kernel Oops
  after few seconds:

  BUG: unable to handle kernel paging request at f88bbc30
  [..]
  Modules linked in: ipv6 [last unloaded: 6lowpan]
  Call Trace:
   [<c012af4c>] ? call_timer_fn+0x54/0xb3
   [<c012aef8>] ? process_timeout+0xa/0xa
   [<c012b66b>] run_timer_softirq+0x140/0x15f

Problem is that incomplete frags are still around after unload; when
their frag expire timer fires, we get crash.

When a netns is removed (also done when unloading module), inet_frag
calls the evictor with 'force' argument to purge remaining frags.

The evictor loop terminates when accounted memory ('work') drops to 0
or the lru-list becomes empty.  However, the mem accounting is done
via percpu counters and may not be accurate, i.e. loop may terminate
prematurely.

Alter evictor to only stop once the lru list is empty when force is
requested.

Reported-by: Phoebe Buckheister <phoebe.buckheister@itwm.fraunhofer.de>
Reported-by: Alexander Aring <alex.aring@gmail.com>
Tested-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net: unix: non blocking recvmsg() should not return -EINTR

[ Upstream commit de1443916791d75fdd26becb116898277bb0273f ]

Some applications didn't expect recvmsg() on a non blocking socket
could return -EINTR. This possibility was added as a side effect
of commit b3ca9b02b00704 ("net: fix multithreaded signal handling in
unix recv routines").

To hit this bug, you need to be a bit unlucky, as the u->readlock
mutex is usually held for very small periods.

Fixes: b3ca9b02b00704 ("net: fix multithreaded signal handling in unix recv routines")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Rainer Weikusat <rweikusat@mobileactivedefense.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ipv6: Fix exthdrs offload registration.

[ Upstream commit d2d273ffabd315eecefce21a4391d44b6e156b73 ]

Without this fix, ipv6_exthdrs_offload_init doesn't register IPPROTO_DSTOPTS
offload, but returns 0 (as the IPPROTO_ROUTING registration actually succeeds).

This then causes the ipv6_gso_segment to drop IPv6 packets with IPPROTO_DSTOPTS
header.

The issue detected and the fix verified by running MS HCK Offload LSO test on
top of QEMU Windows guests, as this test sends IPv6 packets with
IPPROTO_DSTOPTS.

Signed-off-by: Anton Nayshtut <anton@swortex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ipv6: don't set DST_NOCOUNT for remotely added routes

[ Upstream commit c88507fbad8055297c1d1e21e599f46960cbee39 ]

DST_NOCOUNT should only be used if an authorized user adds routes
locally. In case of routes which are added on behalf of router
advertisments this flag must not get used as it allows an unlimited
number of routes getting added remotely.

Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
vlan: Set correct source MAC address with TX VLAN offload enabled

[ Upstream commit dd38743b4cc2f86be250eaf156cf113ba3dd531a ]

With TX VLAN offload enabled the source MAC address for frames sent using the
VLAN interface is currently set to the address of the real interface. This is
wrong since the VLAN interface may be configured with a different address.

The bug was introduced in commit 2205369a314e12fcec4781cc73ac9c08fc2b47de
("vlan: Fix header ops passthru when doing TX VLAN offload.").

This patch sets the source address before calling the create function of the
real interface.

Signed-off-by: Peter Boström <peter.bostrom@netrounds.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tcp: tcp_release_cb() should release socket ownership

[ Upstream commit c3f9b01849ef3bc69024990092b9f42e20df7797 ]

Lars Persson reported following deadlock :

-000 |M:0x0:0x802B6AF8(asm) <-- arch_spin_lock
-001 |tcp_v4_rcv(skb = 0x8BD527A0) <-- sk = 0x8BE6B2A0
-002 |ip_local_deliver_finish(skb = 0x8BD527A0)
-003 |__netif_receive_skb_core(skb = 0x8BD527A0, ?)
-004 |netif_receive_skb(skb = 0x8BD527A0)
-005 |elk_poll(napi = 0x8C770500, budget = 64)
-006 |net_rx_action(?)
-007 |__do_softirq()
-008 |do_softirq()
-009 |local_bh_enable()
-010 |tcp_rcv_established(sk = 0x8BE6B2A0, skb = 0x87D3A9E0, th = 0x814EBE14, ?)
-011 |tcp_v4_do_rcv(sk = 0x8BE6B2A0, skb = 0x87D3A9E0)
-012 |tcp_delack_timer_handler(sk = 0x8BE6B2A0)
-013 |tcp_release_cb(sk = 0x8BE6B2A0)
-014 |release_sock(sk = 0x8BE6B2A0)
-015 |tcp_sendmsg(?, sk = 0x8BE6B2A0, ?, ?)
-016 |sock_sendmsg(sock = 0x8518C4C0, msg = 0x87D8DAA8, size = 4096)
-017 |kernel_sendmsg(?, ?, ?, ?, size = 4096)
-018 |smb_send_kvec()
-019 |smb_send_rqst(server = 0x87C4D400, rqst = 0x87D8DBA0)
-020 |cifs_call_async()
-021 |cifs_async_writev(wdata = 0x87FD6580)
-022 |cifs_writepages(mapping = 0x852096E4, wbc = 0x87D8DC88)
-023 |__writeback_single_inode(inode = 0x852095D0, wbc = 0x87D8DC88)
-024 |writeback_sb_inodes(sb = 0x87D6D800, wb = 0x87E4A9C0, work = 0x87D8DD88)
-025 |__writeback_inodes_wb(wb = 0x87E4A9C0, work = 0x87D8DD88)
-026 |wb_writeback(wb = 0x87E4A9C0, work = 0x87D8DD88)
-027 |wb_do_writeback(wb = 0x87E4A9C0, force_wait = 0)
-028 |bdi_writeback_workfn(work = 0x87E4A9CC)
-029 |process_one_work(worker = 0x8B045880, work = 0x87E4A9CC)
-030 |worker_thread(__worker = 0x8B045880)
-031 |kthread(_create = 0x87CADD90)
-032 |ret_from_kernel_thread(asm)

Bug occurs because __tcp_checksum_complete_user() enables BH, assuming
it is running from softirq context.

Lars trace involved a NIC without RX checksum support but other points
are problematic as well, like the prequeue stuff.

Problem is triggered by a timer, that found socket being owned by user.

tcp_release_cb() should call tcp_write_timer_handler() or
tcp_delack_timer_handler() in the appropriate context :

BH disabled and socket lock held, but 'owned' field cleared,
as if they were running from timer handlers.

Fixes: 6f458dfb4092 ("tcp: improve latencies of timer triggered events")
Reported-by: Lars Persson <lars.persson@axis.com>
Tested-by: Lars Persson <lars.persson@axis.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net: socket: error on a negative msg_namelen

[ Upstream commit dbb490b96584d4e958533fb637f08b557f505657 ]

When copying in a struct msghdr from the user, if the user has set the
msg_namelen parameter to a negative value it gets clamped to a valid
size due to a comparison between signed and unsigned values.

Ensure the syscall errors when the user passes in a negative value.

Signed-off-by: Matthew Leach <matthew.leach@arm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ipv6: Avoid unnecessary temporary addresses being generated

[ Upstream commit ecab67015ef6e3f3635551dcc9971cf363cc1cd5 ]

tmp_prefered_lft is an offset to ifp->tstamp, not now. Therefore
age needs to be added to the condition.

Age calculation in ipv6_create_tempaddr is different from the one
in addrconf_verify and doesn't consider ADDRCONF_TIMER_FUZZ_MINUS.
This can cause age in ipv6_create_tempaddr to be less than the one
in addrconf_verify and therefore unnecessary temporary address to
be generated.
Use age calculation as in addrconf_modify to avoid this.

Signed-off-by: Heiner Kallweit <heiner.kallweit@web.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ipv6: ip6_append_data_mtu do not handle the mtu of the second fragment properly

[ Upstream commit e367c2d03dba4c9bcafad24688fadb79dd95b218 ]

In ip6_append_data_mtu(), when the xfrm mode is not tunnel(such as
transport),the ipsec header need to be added in the first fragment, so the mtu
will decrease to reserve space for it, then the second fragment come, the mtu
should be turn back, as the commit 0c1833797a5a6ec23ea9261d979aa18078720b74
said.  however, in the commit a493e60ac4bbe2e977e7129d6d8cbb0dd236be, it use
*mtu = min(*mtu, ...) to change the mtu, which lead to the new mtu is alway
equal with the first fragment's. and cannot turn back.

when I test through  ping6 -c1 -s5000 $ip (mtu=1280):
...frag (0|1232) ESP(spi=0x00002000,seq=0xb), length 1232
...frag (1232|1216)
...frag (2448|1216)
...frag (3664|1216)
...frag (4880|164)

which should be:
...frag (0|1232) ESP(spi=0x00001000,seq=0x1), length 1232
...frag (1232|1232)
...frag (2464|1232)
...frag (3696|1232)
...frag (4928|116)

so delete the min() when change back the mtu.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Fixes: 75a493e60ac4bb ("ipv6: ip6_append_data_mtu did not care about pmtudisc and frag_size")
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
vxlan: fix potential NULL dereference in arp_reduce()

[ Upstream commit 7346135dcd3f9b57f30a5512094848c678d7143e ]

This patch fixes a NULL pointer dereference in the event of an
skb allocation failure in arp_reduce().

Signed-Off-By: David L Stevens <dlstevens@us.ibm.com>
Acked-by: Cong Wang <cwang@twopensource.com>

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
rtnetlink: fix fdb notification flags

[ Upstream commit 1c104a6bebf3c16b6248408b84f91d09ac8a26b6 ]

Commit 3ff661c38c84 ("net: rtnetlink notify events for FDB NTF_SELF adds and
deletes") reuses the function nlmsg_populate_fdb_fill() to notify fdb events.
But this function was used only for dump and thus was always setting the
flag NLM_F_MULTI, which is wrong in case of a single notification.

Libraries like libnl will wait forever for NLMSG_DONE.

CC: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ipmr: fix mfc notification flags

[ Upstream commit 65886f439ab0fdc2dff20d1fa87afb98c6717472 ]

Commit 8cd3ac9f9b7b ("ipmr: advertise new mfc entries via rtnl") reuses the
function ipmr_fill_mroute() to notify mfc events.
But this function was used only for dump and thus was always setting the
flag NLM_F_MULTI, which is wrong in case of a single notification.

Libraries like libnl will wait forever for NLMSG_DONE.

CC: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>