iterates through the opened files in given descriptor table,
calling a supplied function; we stop once non-zero is returned.
Callback gets struct file *, descriptor number and const void *
argument passed to iterator.  It is called with files->file_lock
held, so it is not allowed to block.

tty_io, netprio_cgroup and selinux flush_unauthorized_files()
converted to its use.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

no callers outside of fs/file.c left
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

nobody uses those outside anymore.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

analog of dup2(), except that it takes struct file * as source.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

... and add cond_resched() there, while we are at it.  We can
get large latencies as is...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Similar situation to that of __alloc_fd(); do not use unless you
really have to.  You should not touch any descriptor table other
than your own; it's a sure sign of a really bad API design.

As with __alloc_fd(), you *must* use a first-class reference to
struct files_struct; something obtained by get_files_struct(some task)
(let alone direct task->files) will not do.  It must be either
current->files, or obtained by get_files_struct(current) by the
owner of that sucker and given to you.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

embedded case isn't hit anymore
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

At that point nobody can see us anyway; everything that
looks at files_fdtable(files) is separated from the
guts of put_files_struct(files) - either since files is
current->files or because we fetched it under task_lock()
and hadn't dropped that yet, or because we'd bumped
files->count while holding task_lock()...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Essentially, alloc_fd() in a files_struct we own a reference to.
Most of the time wanting to use it is a sign of lousy API
design (such as android/binder).  It's *not* a general-purpose
interface; better that than open-coding its guts, but again,
playing with other process' descriptor table is a sign of bad
design.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

... except for one in android, where the check is different
and already done in caller.  No need to recalculate rlimit
many times in alloc_fd() either.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

* do copy_to_user() before prepare_for_access_response(); that kills
the need in remove_access_response().
* don't do fd_install() until we are past the last possible failure
exit.  Don't use sys_close() on cleanup side - just put_unused_fd()
and fput().  Less racy that way...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

don't mess with sys_close() if copy_to_user() fails; just postpone
fd_install() until we know it hasn't.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

we really shouldn't do get_files_struct() on a different process
and use it to modify the sucker later on.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

The only difference between autofs_dev_ioctl_fd_install() and
fd_install() is __set_close_on_exec() done by the latter.  Just
use get_unused_fd_flags(O_CLOEXEC) to allocate the descriptor
and be done with that...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

... and get_unused_fd() a macro around it
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Both modular callers of sock_map_fd() had been buggy; sctp one leaks
descriptor and file if copy_to_user() fails, 9p one shouldn't be
exposing file in the descriptor table at all.

Switch both to sock_alloc_file(), export it, unexport sock_map_fd() and
make it static.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Pull more networking fixes from David Miller:

 1) Eric Dumazet discovered and fixed what turned out to be a family of
    bugs.  These functions were using pskb_may_pull() which might need
    to reallocate the linear SKB data buffer, but the callers were not
    expecting this possibility.  The callers have cached pointers to the
    packet header areas, and would need to reload them if we were to
    continue using pskb_may_pull().

    So they could end up reading garbage.

    It's easier to just change these RAW4/RAW6/MIP6 routines to use
    skb_header_pointer() instead of pskb_may_pull(), which won't modify
    the linear SKB data area.

 2) Dave Jone's syscall spammer caught a case where a non-TCP socket can
    call down into the TCP keepalive code.  The case basically involves
    creating a raw socket with sk_protocol == IPPROTO_TCP, then calling
    setsockopt(sock_fd, SO_KEEPALIVE, ...)

    Fixed by Eric Dumazet.

 3) Bluetooth devices do not get configured properly while being powered
    on, resulting in always using legacy pairing instead of SSP.  Fix
    from Andrzej Kaczmarek.

 4) Bluetooth cancels delayed work erroneously, put stricter checks in
    place.  From Andrei Emeltchenko.

 5) Fix deadlock between cfg80211_mutex and reg_regdb_search_mutex in
    cfg80211, from Luis R.  Rodriguez.

 6) Fix interrupt double release in iwlwifi, from Emmanuel Grumbach.

 7) Missing module license in bcm87xx driver, from Peter Huewe.

 8) Team driver can lose port changed events when adding devices to a
    team, fix from Jiri Pirko.

 9) Fix endless loop when trying ot unregister PPPOE device in zombie
    state, from Xiaodong Xu.

10) batman-adv layer needs to set MAC address of software device
    earlier, otherwise we call tt_local_add with it uninitialized.

11) Fix handling of KSZ8021 PHYs, it's matched currently by KS8051 but
    that doesn't program the device properly.  From Marek Vasut.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  ipv6: mip6: fix mip6_mh_filter()
  ipv6: raw: fix icmpv6_filter()
  net: guard tcp_set_keepalive() to tcp sockets
  phy/micrel: Add missing header to micrel_phy.h
  phy/micrel: Rename KS80xx to KSZ80xx
  phy/micrel: Implement support for KSZ8021
  batman-adv: Fix symmetry check / route flapping in multi interface setups
  batman-adv: Fix change mac address of soft iface.
  pppoe: drop PPPOX_ZOMBIEs in pppoe_release
  team: send port changed when added
  ipv4: raw: fix icmp_filter()
  net/phy/bcm87xx: Add MODULE_LICENSE("GPL") to GPL driver
  iwlwifi: don't double free the interrupt in failure path
  cfg80211: fix possible circular lock on reg_regdb_search()
  Bluetooth: Fix not removing power_off delayed work
  Bluetooth: Fix freeing uninitialized delayed works
  Bluetooth: mgmt: Fix enabling LE while powered off
  Bluetooth: mgmt: Fix enabling SSP while powered off

mip6_mh_filter() should not modify its input, or else its caller
would need to recompute ipv6_hdr() if skb->head is reallocated.

Use skb_header_pointer() instead of pskb_may_pull()
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Included fixes:
- fix the behaviour of batman-adv in case of virtual interface MAC change event
- fix symmetric link check in neighbour selection
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

icmpv6_filter() should not modify its input, or else its caller
would need to recompute ipv6_hdr() if skb->head is reallocated.

Use skb_header_pointer() instead of pskb_may_pull() and
change the prototype to make clear both sk and skb are const.

Also, if icmpv6 header cannot be found, do not deliver the packet,
as we do in IPv4.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pull SuperH fix from Paul Mundt:
 "One last minute regression fix.."

* tag 'sh-for-linus' of git://github.com/pmundt/linux-sh:
  sh: pfc: Fix up GPIO mux type reconfig case.

Merge misc fixes from Andrew Morton:
 "One maintainer change and three bugfixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (4 commits)
  c/r: prctl: fix build error for no-MMU case
  lib/flex_proportions.c: fix corruption of denominator in flexible proportions
  checksyscalls: fix "here document" handling
  pwm-backlight: take over maintenance

Commit 1ad75b9e ("c/r: prctl: add minimal address test to
PR_SET_MM") added some address checking to prctl_set_mm() used by
checkpoint-restore.  This causes a build error for no-MMU systems:

   kernel/sys.c: In function 'prctl_set_mm':
   kernel/sys.c:1868:34: error: 'mmap_min_addr' undeclared (first use in this function)

The test for mmap_min_addr doesn't make a lot of sense for no-MMU code
as noted in commit 6e141546 ("NOMMU: Optimise away the
{dac_,}mmap_min_addr tests").

This patch defines mmap_min_addr as 0UL in the no-MMU case so that the
compiler will optimize away tests for "addr < mmap_min_addr".
Signed-off-by: NMark Salter <msalter@redhat.com>
Reviewed-by: NCyrill Gorcunov <gorcunov@openvz.org>
Cc: <stable@vger.kernel.org>	[3.6.x]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When racing with CPU hotplug, percpu_counter_sum() can return negative
values for the number of observed events.

This confuses fprop_new_period(), which uses unsigned type and as a
result number of events is set to big *positive* number.  From that
moment on, things go pear shaped and can result e.g.  in division by
zero as denominator is later truncated to 32-bits.

This bug causes a divide-by-zero oops in bdi_dirty_limit() in Borislav's
3.6.0-rc6 based kernel.

Fix the issue by using a signed type in fprop_new_period().  That makes
us bail out from the function without doing anything (mistakenly)
thinking there are no events to age.  That makes aging somewhat
inaccurate but getting accurate data would be rather hard.
Signed-off-by: NJan Kara <jack@suse.cz>
Reported-by: NBorislav Petkov <bp@amd64.org>
Reported-by: NSrivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

"echo" doesn't read from stdin, therefore the checksyscalls script didn't
warn about not implemented system calls anymore since 29dc54c6
("checksyscalls: Use arch/x86/syscalls/syscall_32.tbl as source").

Use "cat" instead of "echo" which handles this correctly.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Cc: Michal Marek <mmarek@suse.cz>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since the pwm-backlight driver is lacking a proper maintainer and is the
heaviest user of the PWM framework I'm taking over maintenance.
Signed-off-by: NThierry Reding <thierry.reding@avionic-design.de>
Acked-by: NArun Murthy <arun.murthy@stericsson.com>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Robert Morell <rmorell@nvidia.com>
Cc: Dilan Lee <dilee@nvidia.com>
Cc: Axel Lin <axel.lin@gmail.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: NSachin Kamat <sachin.kamat@linaro.org>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Some drivers need to switch pin states between GPIO and pin function at
runtime, which was inadvertently broken in the pinctrl driver for GPIOs
being bound to a specific direction.

This fixes up the request path to ensure that previously configured GPIOs
don't cause us to inadvertently error out with an unsupported mux on
reconfig, which in practice is primarily aimed at trapping pull-up/down
users that have yet to be implemented under the new API.

Fixes up regressions in the TPU PWM driver, amongst others.
Reported-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: NLaurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

John W. Linville says:

====================
Please pull this last(?) batch of fixes intended for 3.6...

For the Bluetooth bits, Gustavo says this:

"Here goes probably my last update to 3.6. It includes the two patches
you were ok last week(from Andrzej Kaczmarek), those are critical
ones, and two other fixes one for a system crash and the other for
a missing lockdep annotation."

The referenced fixes from Andrzej prevent attempts to configure devices
that are powered-off.

Along with the Bluetooth fixes, there are a couple of 802.11 fixes.
Emmanuel Grumbach gives us an iwlwifi fix to prevent releasing an
interrupt twice.  Luis R. Rodriguez provides a fix for a possible
circular lock dependency in the cfg80211 regulatory enforcement code.

All of these have been in linux-next for a few days.  I hope they are
not too late to make the 3.6 release!
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pull tile gxio ABI fix from Chris Metcalf:
 "This fixes a last-minute change in the Tilera hypervisor ABI for TRIO
  (PCI root complex) support.  We've locked in this ABI going forward
  and will make sure no further ABI changes like this occur."

* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile:
  tile: gxio iorpc numbering change for TRIO interface

Pull vfio fixes from Alex Williamson:
 "VFIO doc update and virqfd race fix"

* tag 'vfio-for-linus' of git://github.com/awilliam/linux-vfio:
  vfio: Fix virqfd release race
  vfio: Trivial Documentation correction