cifs: delay super block destruction until all cifsFileInfo objects are gone

cifsFileInfo objects hold references to dentries and it is possible that
these will still be around in workqueues when VFS decides to kill super
block during unmount.

This results in panics like this one:
BUG: Dentry ffff88001f5e76c0{i=66b4a,n=1M-2} still in use (1) [unmount of cifs cifs]
------------[ cut here ]------------
kernel BUG at fs/dcache.c:943!
[..]
Process umount (pid: 1781, threadinfo ffff88003d6e8000, task ffff880035eeaec0)
[..]
Call Trace:
 [<ffffffff811b44f3>] shrink_dcache_for_umount+0x33/0x60
 [<ffffffff8119f7fc>] generic_shutdown_super+0x2c/0xe0
 [<ffffffff8119f946>] kill_anon_super+0x16/0x30
 [<ffffffffa036623a>] cifs_kill_sb+0x1a/0x30 [cifs]
 [<ffffffff8119fcc7>] deactivate_locked_super+0x57/0x80
 [<ffffffff811a085e>] deactivate_super+0x4e/0x70
 [<ffffffff811bb417>] mntput_no_expire+0xd7/0x130
 [<ffffffff811bc30c>] sys_umount+0x9c/0x3c0
 [<ffffffff81657c19>] system_call_fastpath+0x16/0x1b

Fix this by making each cifsFileInfo object hold a reference to cifs
super block, which implicitly keeps VFS super block around as well.

Signed-off-by: Mateusz Guzik <mguzik@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Cc: <stable@vger.kernel.org>
Reported-and-Tested-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
USB: quatech2: only write to the tty if the port is open.

The commit 2e124b4a390ca85325fae75764bef92f0547fa25 removed the checks
that prevented qt2_process_read_urb() from trying to put chars into
ttys that weren't actually opened.  This resulted in 'tty is NULL'
warnings from flush_to_ldisc() when the device was used.

The devices use just one read urb for all ports.  As a result
qt2_process_read_urb() may be called with the current port set to a
port number that has not been opened.  Add a check if the port is open
before calling tty_flip_buffer_push().

Signed-off-by: Bill Pemberton <wfp5p@virginia.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
perf annotate: Fix build with NO_NEWT=1

Commit 18c9e5c "Make it to be able to skip unannotatable symbols" broke
the build with NO_NEWT=1:

   CC builtin-annotate.o
builtin-annotate.c: In function 'hists__find_annotations':
builtin-annotate.c:161:4: error: duplicate case value
builtin-annotate.c:154:4: error: previously used here
make: *** [builtin-annotate.o] Error 1

This is because without NEWT support K_LEFT is #defined to -1 in
utils/hist.h

Fix it by shifting the K_LEFT/K_RIGHT #defines out of the likely range
of error values.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1361854923-1814-1-git-send-email-michael@ellerman.id.au
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf report: Fix build with NO_NEWT=1

Commit ad0de09 "Enable the runtime switching of perf data file" broke
the build with NO_NEWT=1:

    CC builtin-report.o
builtin-report.c: In function '__cmd_report':
builtin-report.c:479:15: error: 'K_SWITCH_INPUT_DATA' undeclared (first use in this function)
builtin-report.c:479:15: note: each undeclared identifier is reported only once for each function it appears in
builtin-report.c: In function 'cmd_report':
builtin-report.c:823:13: error: 'K_SWITCH_INPUT_DATA' undeclared (first use in this function)
make: *** [builtin-report.o] Error 1

Fix it by adding a dummy definition of K_SWITCH_INPUT_DATA.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Namhyung Kim <namhyung.kim@lge.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1361854923-1814-2-git-send-email-michael@ellerman.id.au
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf tools: check if -DFORTIFY_SOURCE=2 is allowed

It seems gcc (4.7.2) defines _FORTIFY_SOURCE internally and becomes
confused when it sees another definition in flags.

For me, build failed like this:

CHK glibc
Makefile:548: *** No gnu/libc-version.h found, please install glibc-dev[el]/glibc-static. Stop.

and only with V=1 it printed:

<command-line>:0:0: error: "_FORTIFY_SOURCE" redefined [-Werror]
<stdin>:1:0: note: this is the location of the previous definition

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1361113416-8662-1-git-send-email-marcin.slusarz@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf record: Fix -C option

Currently the -C option does not work for record command, because of the
targets mismatch when synthesizing threads.

Fixing this by using proper target interface for the synthesize
decision.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Reported-by: Oleg Nesterov <oleg@redhat.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1361785972-7431-2-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
libtraceevent: Remove hard coded include to /usr/local/include in Makefile

having /usr/local/include hardcoded into the makefile is not necessary
as this is automatically included by GCC. It also infects cross-compile
builds with the host systems includes.

Signed-off-by: Jack Mitchell <jack.mitchell@dbbroadcast.co.uk>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1362741712-21308-1-git-send-email-ml@communistcode.co.uk
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf probe: Fix segfault

Fix segfault in perf probe due to a bug introduced by commit d8639f068
(perf tools: Stop using 'self' in strlist).

Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Acked-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/20130312090217.GC4668@in.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf/POWER7: Create a sysfs format entry for Power7 events

Create a sysfs entry, '/sys/bus/event_source/devices/cpu/format/event'
which describes the format of the POWER7 PMU events.

This code is based on corresponding code in x86.

Changelog[v4]:  [Michael Ellerman, Paul Mckerras] The event format is different
		for other POWER cpus. So move the code to POWER7-specific,
		power7-pmu.c Also, the POWER7 format uses bits 0-19 not 0-20.

Changelog[v2]: [Jiri Osla] Use PMU_FORMAT_ATTR rather than duplicating code.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Tested-by: Michael Ellerman <michael@ellerman.id.au>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Anton Blanchard <anton@au1.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: benh@kernel.crashing.org
Cc: linuxppc-dev@ozlabs.org
Link: http://lkml.kernel.org/r/20130306054826.GA14627@us.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
drm/i915: restrict kernel address leak in debugfs

Masks kernel address info-leak in object dumps with the %pK suffix,
so they cannot be used to target kernel memory corruption attacks if
the kptr_restrict sysctl is set.

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
drm/i915: bounds check execbuffer relocation count

It is possible to wrap the counter used to allocate the buffer for
relocation copies. This could lead to heap writing overflows.

CVE-2013-0913

v3: collapse test, improve comment
v2: move check into validate_exec_list

Signed-off-by: Kees Cook <keescook@chromium.org>
Reported-by: Pinkie Pie
Cc: stable@vger.kernel.org
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
batman-adv: replace redundant primary_if_get calls

The batadv_priv struct carries a pointer to its own interface
struct. Therefore, it is not necessary to retrieve the soft_iface
via the primary interface.

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
batman-adv: Return reason for failure in batadv_check_unicast_packet()

batadv_check_unicast_packet() is changed to return a value based on the
reason to drop the packet, which will be useful information for
future users of batadv_check_unicast_packet().

Signed-off-by: Martin Hundebøll <martin@hundeboll.net>
Acked-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
batman-adv: don't use !! in bool conversion

In C standard any expression different from 0 will be converted to
'true' when casting to bool (whatever is the length of the value).
Therefore all the "!!" conversions can be removed.

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
batman-adv: network coding - add the initial infrastructure code

Network coding exploits the 802.11 shared medium to allow multiple
packets to be sent in a single transmission. In brief, a relay can XOR
two packets, and send the coded packet to two destinations. The
receivers can decode one of the original packets by XOR'ing the coded
packet with the other original packet. This will lead to increased
throughput in topologies where two packets cross one relay.

In a simple topology with three nodes, it takes four transmissions
without network coding to get one packet from Node A to Node B and one
from Node B to Node A:

 1.  Node A  ---- p1 --->  Node R                Node B
 2.  Node A                Node R  <--- p2 ----  Node B
 3.  Node A  <--- p2 ----  Node R                Node B
 4.  Node A                Node R  ---- p1 --->  Node B

With network coding, the relay only needs one transmission, which saves
us one slot of valuable airtime:

 1.  Node A  ---- p1 --->  Node R                Node B
 2.  Node A                Node R  <--- p2 ----  Node B
 3.  Node A  <- p1 x p2 -  Node R  - p1 x p2 ->  Node B

The same principle holds for a topology including five nodes. Here the
packets from Node A and Node B are overheard by Node C and Node D,
respectively. This allows Node R to send a network coded packet to save
one transmission:

   Node A                  Node B

    |     \              /    |
    |      p1          p2     |
    |       \          /      |
    p1       > Node R <       p2
    |                         |
    |         /      \        |
    |    p1 x p2    p1 x p2   |
    v       /          \      v
           /            \
   Node C <              > Node D

More information is available on the open-mesh.org wiki[1].

This patch adds the initial code to support network coding in
batman-adv. It sets up a worker thread to do house keeping and adds a
sysfs file to enable/disable network coding. The feature is disabled by
default, as it requires a wifi-driver with working promiscuous mode, and
also because it adds a small delay at each hop.

[1] http://www.open-mesh.org/projects/batman-adv/wiki/Catwoman

Signed-off-by: Martin Hundebøll <martin@hundeboll.net>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
batman-adv: network coding - detect coding nodes and remove these after timeout

To use network coding efficiently, a relay must know when neighbor nodes
are likely to have enough information to be able to decode a network
coded packet. This is detected by using OGMs from batman-adv to discover
when one neighbor is in range of another neighbor. The relay check the
TLL to detect when an OGM is forwarded from one neighbor by another
neighbor, and thereby knows that the two neighbors are in range and thus
overhear packets sent by each other.

This information is saved in the orig_node struct to be used when
searching for coding opportunities. Two lists are added to the
orig_node struct: One for neighbors that can hear the orig_node
(outgoing nc_nodes) and one for neighbors that the orig_node can hear
(incoming nc_nodes).

Information about nc_nodes is kept for 10 seconds and is available
through debugfs in batman_adv/nc_nodes to use when debugging network
coding.

Signed-off-by: Martin Hundebøll <martin@hundeboll.net>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
batman-adv: network coding - buffer unicast packets before forward

Two be able to network code two packets, one packet must be buffered
until the next is available. This is done in a "coding buffer", which is
essentially a hash table with lists of packets. Each entry in the hash
table corresponds to a specific src-dst pair, which has a linked list of
packets that are buffered.

This patch adds skbs to the buffer just before forwarding them. The
buffer is traversed every 10 ms, where timed skbs are removed from the
buffer and transmitted. To allow experiments with the network coding
scheme, the timeout is tunable through a file in debugfs.

Signed-off-by: Martin Hundebøll <martin@hundeboll.net>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
batman-adv: network coding - code and transmit packets if possible

Before adding forward-skbs to the coding buffer, the buffer is searched
for a potential coding opportunity. If one is found, the two packets are
network coded and transmitted right away. If not, the forward-skb is
added to the buffer.

Network coded packets are transmitted with information about the two
receivers and the two coded packets. The first receiver is given by the
MAC header, while the second is given in the payload/bat-header. The
second receiver uses promiscuous mode to receive the packet and check
the second destination.

Signed-off-by: Martin Hundebøll <martin@hundeboll.net>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
batman-adv: network coding - save overheard and tx packets for decoding

To be able to decode a network coded packet, a node must already know
one of the two coded packets. This is done by buffering skbs before
transmission and buffering packets sniffed with promiscuous mode from
other hosts.

Packets are kept in a buffer similar to the one with forward-skbs: A
hash table, where each entry, which corresponds to a src-dst pair, has a
linked list packets.

Signed-off-by: Martin Hundebøll <martin@hundeboll.net>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
batman-adv: network coding - receive coded packets and decode them

When receiving a network coded packet, the decoding buffer is searched
for a packet to use for decoding. The source, destination, and crc32 from
the coded packet is used to identify the wanted packet. The decoded
packet is passed to the usual unicast receiver function, as had it never
been network coded.

Signed-off-by: Martin Hundebøll <martin@hundeboll.net>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>