TTY: do not reset master's packet mode

commit b81273a132177edd806476b953f6afeb17b786d5 upstream.

Now that login from util-linux is forced to drop all references to a
TTY which it wants to hangup (to reach reference count 1) we are
seeing issues with telnet. When login closes its last reference to the
slave PTY, it also resets packet mode on the *master* side. And we
have a race here.

What telnet does is fork+exec of `login'. Then there are two
scenarios:
* `login' closes the slave TTY and resets thus master's packet mode,
  but even now telnet properly sets the mode, or
* `telnetd' sets packet mode on the master, `login' closes the slave
  TTY and resets master's packet mode.

The former case is OK. However the latter happens in much more cases,
by the order of magnitude to be precise. So when one tries to login to
such a messed telnet setup, they see the following:
inux login:
            ogin incorrect

Note the missing first letters -- telnet thinks it is still in the
packet mode, so when it receives "linux login" from `login', it
considers "l" as the type of the packet and strips it.

SuS does not mention how the implementation should behave. Both BSDs I
checked (Free and Net) do not reset the flag upon the last close.

By this I am resurrecting an old bug, see References. We are hitting
it regularly now, i.e. with updated util-linux, ergo login.

Here, I am changing a behavior introduced back in 2.1 times. It would
better have a long time testing before goes upstream.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Cc: Bryan Mason <bmason@redhat.com>
References: https://lkml.org/lkml/2009/11/11/223
References: https://bugzilla.redhat.com/show_bug.cgi?id=504703
References: https://bugzilla.novell.com/show_bug.cgi?id=797042
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
perf,x86: fix kernel crash with PEBS/BTS after suspend/resume

commit 1d9d8639c063caf6efc2447f5f26aa637f844ff6 upstream.

This patch fixes a kernel crash when using precise sampling (PEBS)
after a suspend/resume. Turns out the CPU notifier code is not invoked
on CPU0 (BP). Therefore, the DS_AREA (used by PEBS) is not restored properly
by the kernel and keeps it power-on/resume value of 0 causing any PEBS
measurement to crash when running on CPU0.

The workaround is to add a hook in the actual resume code to restore
the DS Area MSR value. It is invoked for all CPUS. So for all but CPU0,
the DS_AREA will be restored twice but this is harmless.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
perf,x86: fix wrmsr_on_cpu() warning on suspend/resume

commit 2a6e06b2aed6995af401dcd4feb5e79a0c7ea554 upstream.

Commit 1d9d8639c063 ("perf,x86: fix kernel crash with PEBS/BTS after
suspend/resume") fixed a crash when doing PEBS performance profiling
after resuming, but in using init_debug_store_on_cpu() to restore the
DS_AREA mtrr it also resulted in a new WARN_ON() triggering.

init_debug_store_on_cpu() uses "wrmsr_on_cpu()", which in turn uses CPU
cross-calls to do the MSR update.  Which is not really valid at the
early resume stage, and the warning is quite reasonable.  Now, it all
happens to _work_, for the simple reason that smp_call_function_single()
ends up just doing the call directly on the CPU when the CPU number
matches, but we really should just do the wrmsr() directly instead.

This duplicates the wrmsr() logic, but hopefully we can just remove the
wrmsr_on_cpu() version eventually.

Reported-and-tested-by: Parag Warudkar <parag.lkml@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
perf,x86: fix link failure for non-Intel configs

commit 6c4d3bc99b3341067775efd4d9d13cc8e655fd7c upstream.

Commit 1d9d8639c063 ("perf,x86: fix kernel crash with PEBS/BTS after
suspend/resume") introduces a link failure since
perf_restore_debug_store() is only defined for CONFIG_CPU_SUP_INTEL:

	arch/x86/power/built-in.o: In function `restore_processor_state':
	(.text+0x45c): undefined reference to `perf_restore_debug_store'

Fix it by defining the dummy function appropriately.

Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
l2tp: Restore socket refcount when sendmsg succeeds

[ Upstream commit 8b82547e33e85fc24d4d172a93c796de1fefa81a ]

The sendmsg() syscall handler for PPPoL2TP doesn't decrease the socket
reference counter after successful transmissions. Any successful
sendmsg() call from userspace will then increase the reference counter
forever, thus preventing the kernel's session and tunnel data from
being freed later on.

The problem only happens when writing directly on L2TP sockets.
PPP sockets attached to L2TP are unaffected as the PPP subsystem
uses pppol2tp_xmit() which symmetrically increase/decrease reference
counters.

This patch adds the missing call to sock_put() before returning from
pppol2tp_sendmsg().

Signed-off-by: Guillaume Nault <g.nault@alphalink.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
rds: limit the size allocated by rds_message_alloc()

[ Upstream commit ece6b0a2b25652d684a7ced4ae680a863af041e0 ]

Dave Jones reported the following bug:

"When fed mangled socket data, rds will trust what userspace gives it,
and tries to allocate enormous amounts of memory larger than what
kmalloc can satisfy."

WARNING: at mm/page_alloc.c:2393 __alloc_pages_nodemask+0xa0d/0xbe0()
Hardware name: GA-MA78GM-S2H
Modules linked in: vmw_vsock_vmci_transport vmw_vmci vsock fuse bnep dlci bridge 8021q garp stp mrp binfmt_misc l2tp_ppp l2tp_core rfcomm s
Pid: 24652, comm: trinity-child2 Not tainted 3.8.0+ #65
Call Trace:
 [<ffffffff81044155>] warn_slowpath_common+0x75/0xa0
 [<ffffffff8104419a>] warn_slowpath_null+0x1a/0x20
 [<ffffffff811444ad>] __alloc_pages_nodemask+0xa0d/0xbe0
 [<ffffffff8100a196>] ? native_sched_clock+0x26/0x90
 [<ffffffff810b2128>] ? trace_hardirqs_off_caller+0x28/0xc0
 [<ffffffff810b21cd>] ? trace_hardirqs_off+0xd/0x10
 [<ffffffff811861f8>] alloc_pages_current+0xb8/0x180
 [<ffffffff8113eaaa>] __get_free_pages+0x2a/0x80
 [<ffffffff811934fe>] kmalloc_order_trace+0x3e/0x1a0
 [<ffffffff81193955>] __kmalloc+0x2f5/0x3a0
 [<ffffffff8104df0c>] ? local_bh_enable_ip+0x7c/0xf0
 [<ffffffffa0401ab3>] rds_message_alloc+0x23/0xb0 [rds]
 [<ffffffffa04043a1>] rds_sendmsg+0x2b1/0x990 [rds]
 [<ffffffff810b21cd>] ? trace_hardirqs_off+0xd/0x10
 [<ffffffff81564620>] sock_sendmsg+0xb0/0xe0
 [<ffffffff810b2052>] ? get_lock_stats+0x22/0x70
 [<ffffffff810b24be>] ? put_lock_stats.isra.23+0xe/0x40
 [<ffffffff81567f30>] sys_sendto+0x130/0x180
 [<ffffffff810b872d>] ? trace_hardirqs_on+0xd/0x10
 [<ffffffff816c547b>] ? _raw_spin_unlock_irq+0x3b/0x60
 [<ffffffff816cd767>] ? sysret_check+0x1b/0x56
 [<ffffffff810b8695>] ? trace_hardirqs_on_caller+0x115/0x1a0
 [<ffffffff81341d8e>] ? trace_hardirqs_on_thunk+0x3a/0x3f
 [<ffffffff816cd742>] system_call_fastpath+0x16/0x1b
---[ end trace eed6ae990d018c8b ]---

Reported-by: Dave Jones <davej@redhat.com>
Cc: Dave Jones <davej@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Venkat Venkatsubra <venkat.x.venkatsubra@oracle.com>
Signed-off-by: Cong Wang <amwang@redhat.com>
Acked-by: Venkat Venkatsubra <venkat.x.venkatsubra@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
net: ipv6: Don't purge default router if accept_ra=2

[ Upstream commit 3e8b0ac3e41e3c882222a5522d5df7212438ab51 ]

Setting net.ipv6.conf.<interface>.accept_ra=2 causes the kernel
to accept RAs even when forwarding is enabled. However, enabling
forwarding purges all default routes on the system, breaking
connectivity until the next RA is received. Fix this by not
purging default routes on interfaces that have accept_ra=2.

Signed-off-by: Lorenzo Colitti <lorenzo@google.com>
Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
tcp: fix double-counted receiver RTT when leaving  receiver fast path

[ Upstream commit aab2b4bf224ef8358d262f95b568b8ad0cecf0a0 ]

We should not update ts_recent and call tcp_rcv_rtt_measure_ts() both
before and after going to step5. That wastes CPU and double-counts the
receiver-side RTT sample.

Signed-off-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
tun: add a missing nf_reset() in tun_net_xmit()

[ Upstream commit f8af75f3517a24838a36eb5797a1a3e60bf9e276 ]

Dave reported following crash :

general protection fault: 0000 [#1] SMP
CPU 2
Pid: 25407, comm: qemu-kvm Not tainted 3.7.9-205.fc18.x86_64 #1 Hewlett-Packard HP Z400 Workstation/0B4Ch
RIP: 0010:[<ffffffffa0399bd5>]  [<ffffffffa0399bd5>] destroy_conntrack+0x35/0x120 [nf_conntrack]
RSP: 0018:ffff880276913d78  EFLAGS: 00010206
RAX: 50626b6b7876376c RBX: ffff88026e530d68 RCX: ffff88028d158e00
RDX: ffff88026d0d5470 RSI: 0000000000000011 RDI: 0000000000000002
RBP: ffff880276913d88 R08: 0000000000000000 R09: ffff880295002900
R10: 0000000000000000 R11: 0000000000000003 R12: ffffffff81ca3b40
R13: ffffffff8151a8e0 R14: ffff880270875000 R15: 0000000000000002
FS:  00007ff3bce38a00(0000) GS:ffff88029fc40000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 00007fd1430bd000 CR3: 000000027042b000 CR4: 00000000000027e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process qemu-kvm (pid: 25407, threadinfo ffff880276912000, task ffff88028c369720)
Stack:
 ffff880156f59100 ffff880156f59100 ffff880276913d98 ffffffff815534f7
 ffff880276913db8 ffffffff8151a74b ffff880270875000 ffff880156f59100
 ffff880276913dd8 ffffffff8151a5a6 ffff880276913dd8 ffff88026d0d5470
Call Trace:
 [<ffffffff815534f7>] nf_conntrack_destroy+0x17/0x20
 [<ffffffff8151a74b>] skb_release_head_state+0x7b/0x100
 [<ffffffff8151a5a6>] __kfree_skb+0x16/0xa0
 [<ffffffff8151a666>] kfree_skb+0x36/0xa0
 [<ffffffff8151a8e0>] skb_queue_purge+0x20/0x40
 [<ffffffffa02205f7>] __tun_detach+0x117/0x140 [tun]
 [<ffffffffa022184c>] tun_chr_close+0x3c/0xd0 [tun]
 [<ffffffff8119669c>] __fput+0xec/0x240
 [<ffffffff811967fe>] ____fput+0xe/0x10
 [<ffffffff8107eb27>] task_work_run+0xa7/0xe0
 [<ffffffff810149e1>] do_notify_resume+0x71/0xb0
 [<ffffffff81640152>] int_signal+0x12/0x17
Code: 00 00 04 48 89 e5 41 54 53 48 89 fb 4c 8b a7 e8 00 00 00 0f 85 de 00 00 00 0f b6 73 3e 0f b7 7b 2a e8 10 40 00 00 48 85 c0 74 0e <48> 8b 40 28 48 85 c0 74 05 48 89 df ff d0 48 c7 c7 08 6a 3a a0
RIP  [<ffffffffa0399bd5>] destroy_conntrack+0x35/0x120 [nf_conntrack]
 RSP <ffff880276913d78>

This is because tun_net_xmit() needs to call nf_reset()
before queuing skb into receive_queue

Reported-by: Dave Jones <davej@redhat.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
macvlan: Set IFF_UNICAST_FLT flag to prevent  unnecessary promisc mode.

[ Upstream commit 87ab7f6f2874f1115817e394a7ed2dea1c72549e ]

Macvlan already supports hw address filters.  Set the IFF_UNICAST_FLT
so that it doesn't needlesly enter PROMISC mode when macvlans are
stacked.

Signed-of-by: Vlad Yasevich <vyasevic@redhat.com>

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
netlabel: correctly list all the static label mappings

[ Upstream commits 0c1233aba1e948c37f6dc7620cb7c253fcd71ce9 and
  a6a8fe950e1b8596bb06f2c89c3a1a4bf2011ba9 ]

When we have a large number of static label mappings that spill across
the netlink message boundary we fail to properly save our state in the
netlink_callback struct which causes us to repeat the same listings.
This patch fixes this problem by saving the state correctly between
calls to the NetLabel static label netlink "dumpit" routines.

Signed-off-by: Paul Moore <pmoore@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
bridging: fix rx_handlers return code

[ Upstream commit 3bc1b1add7a8484cc4a261c3e128dbe1528ce01f ]

The frames for which rx_handlers return RX_HANDLER_CONSUMED are no longer
counted as dropped. They are counted as successfully received by
'netif_receive_skb'.

This allows network interface drivers to correctly update their RX-OK and
RX-DRP counters based on the result of 'netif_receive_skb'.

Signed-off-by: Cristian Bercaru <B43982@freescale.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
ipv6: stop multicast forwarding to process interface  scoped addresses

[ Upstream commit ddf64354af4a702ee0b85d0a285ba74c7278a460 ]

v2:
a) used struct ipv6_addr_props

v3:
a) reverted changes for ipv6_addr_props

v4:
a) do not use __ipv6_addr_needs_scope_id

Cc: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
rtnl: fix info leak on RTM_GETLINK request for VF  devices

[ Upstream commit 84d73cd3fb142bf1298a8c13fd4ca50fd2432372 ]

Initialize the mac address buffer with 0 as the driver specific function
will probably not fill the whole buffer. In fact, all in-kernel drivers
fill only ETH_ALEN of the MAX_ADDR_LEN bytes, i.e. 6 of the 32 possible
bytes. Therefore we currently leak 26 bytes of stack memory to userland
via the netlink interface.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
dcbnl: fix various netlink info leaks

[ Upstream commit 29cd8ae0e1a39e239a3a7b67da1986add1199fc0 ]

The dcb netlink interface leaks stack memory in various places:
* perm_addr[] buffer is only filled at max with 12 of the 32 bytes but
  copied completely,
* no in-kernel driver fills all fields of an IEEE 802.1Qaz subcommand,
  so we're leaking up to 58 bytes for ieee_ets structs, up to 136 bytes
  for ieee_pfc structs, etc.,
* the same is true for CEE -- no in-kernel driver fills the whole
  struct,

Prevent all of the above stack info leaks by properly initializing the
buffers/structures involved.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
6lowpan: Fix endianness issue in is_addr_link_local().

[ Upstream commit 9026c4927254f5bea695cc3ef2e255280e6a3011 ]

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
drm/i915: Increase the RC6p threshold.

commit 0920a48719f1ceefc909387a64f97563848c7854 upstream.

This increases GEN6_RC6p_THRESHOLD from 100000 to 150000. For some
reason this avoids the gen6_gt_check_fifodbg.isra warnings and
associated GPU lockups, which makes my ivy bridge machine stable.

Signed-off-by: Stéphane Marchesin <marcheu@chromium.org>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
[bwh: Backported to 3.2: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
perf: Revert duplicated commit

This reverts commit 923415295307845e614589c1cce62abedd4d1731
'perf: Fix parsing of __print_flags() in TP_printk()'.  The same
change was already included in 3.2 as commit
d06c27b22aa66e48e32f03f9387328a9af9b0625 but in 3.2.1 this change
was wrongly applied to similar code in a different function.

Thanks to Jiri for pointing this out in 3.0.y.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Andrew Vagin <avagin@openvz.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
i915: initialize CADL in opregion

commit d627b62ff8d4d36761adbcd90ff143d79c94ab22 upstream.

This is rather a hack to fix brightness hotkeys on a Clevo laptop. CADL is not
used anywhere in the driver code at the moment, but it could be used in BIOS as
is the case with the Clevo laptop.

The Clevo B7130 requires the CADL field to contain at least the ID of
the LCD device. If this field is empty, the ACPI methods that are called
on pressing brightness / display switching hotkeys will not trigger a
notification. As a result, it appears as no hotkey has been pressed.

Reference: https://bugs.freedesktop.org/show_bug.cgi?id=45452
Tested-by: Peter Wu <lekensteyn@gmail.com>
Signed-off-by: Peter Wu <lekensteyn@gmail.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
s390/mm: fix flush_tlb_kernel_range()

commit f6a70a07079518280022286a1dceb797d12e1edf upstream.

Our flush_tlb_kernel_range() implementation calls __tlb_flush_mm() with
&init_mm as argument. __tlb_flush_mm() however will only flush tlbs
for the passed in mm if its mm_cpumask is not empty.

For the init_mm however its mm_cpumask has never any bits set. Which in
turn means that our flush_tlb_kernel_range() implementation doesn't
work at all.

This can be easily verified with a vmalloc/vfree loop which allocates
a page, writes to it and then frees the page again. A crash will follow
almost instantly.

To fix this remove the cpumask_empty() check in __tlb_flush_mm() since
there shouldn't be too many mms with a zero mm_cpumask, besides the
init_mm of course.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>