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11097 commits

Author SHA1 Message Date
Kees Cook
800179c9b8 fs: add link restrictions
This adds symlink and hardlink restrictions to the Linux VFS.

Symlinks:

A long-standing class of security issues is the symlink-based
time-of-check-time-of-use race, most commonly seen in world-writable
directories like /tmp. The common method of exploitation of this flaw
is to cross privilege boundaries when following a given symlink (i.e. a
root process follows a symlink belonging to another user). For a likely
incomplete list of hundreds of examples across the years, please see:
http://cve.mitre.org/cgi-bin/cvekey.cgi?keyword=/tmp

The solution is to permit symlinks to only be followed when outside
a sticky world-writable directory, or when the uid of the symlink and
follower match, or when the directory owner matches the symlink's owner.

Some pointers to the history of earlier discussion that I could find:

 1996 Aug, Zygo Blaxell
  http://marc.info/?l=bugtraq&m=87602167419830&w=2
 1996 Oct, Andrew Tridgell
  http://lkml.indiana.edu/hypermail/linux/kernel/9610.2/0086.html
 1997 Dec, Albert D Cahalan
  http://lkml.org/lkml/1997/12/16/4
 2005 Feb, Lorenzo Hernández García-Hierro
  http://lkml.indiana.edu/hypermail/linux/kernel/0502.0/1896.html
 2010 May, Kees Cook
  https://lkml.org/lkml/2010/5/30/144

Past objections and rebuttals could be summarized as:

 - Violates POSIX.
   - POSIX didn't consider this situation and it's not useful to follow
     a broken specification at the cost of security.
 - Might break unknown applications that use this feature.
   - Applications that break because of the change are easy to spot and
     fix. Applications that are vulnerable to symlink ToCToU by not having
     the change aren't. Additionally, no applications have yet been found
     that rely on this behavior.
 - Applications should just use mkstemp() or O_CREATE|O_EXCL.
   - True, but applications are not perfect, and new software is written
     all the time that makes these mistakes; blocking this flaw at the
     kernel is a single solution to the entire class of vulnerability.
 - This should live in the core VFS.
   - This should live in an LSM. (https://lkml.org/lkml/2010/5/31/135)
 - This should live in an LSM.
   - This should live in the core VFS. (https://lkml.org/lkml/2010/8/2/188)

Hardlinks:

On systems that have user-writable directories on the same partition
as system files, a long-standing class of security issues is the
hardlink-based time-of-check-time-of-use race, most commonly seen in
world-writable directories like /tmp. The common method of exploitation
of this flaw is to cross privilege boundaries when following a given
hardlink (i.e. a root process follows a hardlink created by another
user). Additionally, an issue exists where users can "pin" a potentially
vulnerable setuid/setgid file so that an administrator will not actually
upgrade a system fully.

The solution is to permit hardlinks to only be created when the user is
already the existing file's owner, or if they already have read/write
access to the existing file.

Many Linux users are surprised when they learn they can link to files
they have no access to, so this change appears to follow the doctrine
of "least surprise". Additionally, this change does not violate POSIX,
which states "the implementation may require that the calling process
has permission to access the existing file"[1].

This change is known to break some implementations of the "at" daemon,
though the version used by Fedora and Ubuntu has been fixed[2] for
a while. Otherwise, the change has been undisruptive while in use in
Ubuntu for the last 1.5 years.

[1] http://pubs.opengroup.org/onlinepubs/9699919799/functions/linkat.html
[2] http://anonscm.debian.org/gitweb/?p=collab-maint/at.git;a=commitdiff;h=f4114656c3a6c6f6070e315ffdf940a49eda3279

This patch is based on the patches in Openwall and grsecurity, along with
suggestions from Al Viro. I have added a sysctl to enable the protected
behavior, and documentation.

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-29 21:37:58 +04:00
Al Viro
ebfc3b49a7 don't pass nameidata to ->create()
boolean "does it have to be exclusive?" flag is passed instead;
Local filesystem should just ignore it - the object is guaranteed
not to be there yet.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:34:47 +04:00
Al Viro
00cd8dd3bf stop passing nameidata to ->lookup()
Just the flags; only NFS cares even about that, but there are
legitimate uses for such argument.  And getting rid of that
completely would require splitting ->lookup() into a couple
of methods (at least), so let's leave that alone for now...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:34:32 +04:00
Al Viro
0b728e1911 stop passing nameidata * to ->d_revalidate()
Just the lookup flags.  Die, bastard, die...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:34:14 +04:00
Al Viro
30d9049474 kill struct opendata
Just pass struct file *.  Methods are happier that way...
There's no need to return struct file * from finish_open() now,
so let it return int.  Next: saner prototypes for parts in
namei.c

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:39 +04:00
Al Viro
d95852777b make ->atomic_open() return int
Change of calling conventions:
old		new
NULL		1
file		0
ERR_PTR(-ve)	-ve

Caller *knows* that struct file *; no need to return it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:35 +04:00
Al Viro
47237687d7 ->atomic_open() prototype change - pass int * instead of bool *
... and let finish_open() report having opened the file via that sucker.
Next step: don't modify od->filp at all.

[AV: FILE_CREATE was already used by cifs; Miklos' fix folded]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:31 +04:00
Miklos Szeredi
d18e9008c3 vfs: add i_op->atomic_open()
Add a new inode operation which is called on the last component of an open.
Using this the filesystem can look up, possibly create and open the file in one
atomic operation.  If it cannot perform this (e.g. the file type turned out to
be wrong) it may signal this by returning NULL instead of an open struct file
pointer.

i_op->atomic_open() is only called if the last component is negative or needs
lookup.  Handling cached positive dentries here doesn't add much value: these
can be opened using f_op->open().  If the cached file turns out to be invalid,
the open can be retried, this time using ->atomic_open() with a fresh dentry.

For now leave the old way of using open intents in lookup and revalidate in
place.  This will be removed once all the users are converted.

David Howells noticed that if ->atomic_open() opens the file but does not create
it, handle_truncate() will be called on it even if it is not a regular file.
Fix this by checking the file type in this case too.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:04 +04:00
Al Viro
049b3c10ee vfs: update documentation on ->i_dentry handling
we used to need to clean it in RCU callback freeing an inode;
in 3.2 that requirement went away.  Unfortunately, it hadn't
been reflected in Documentation/filesystems/porting.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:32:51 +04:00
Linus Torvalds
8488e4088f Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media fixes from Mauro Carvalho Chehab:
 - Some regression fixes at the audio part for devices with
   cx23885/cx25840
 - A DMA corruption fix at cx231xx
 - two fixes at the winbond IR driver
 - Several fixes for the EXYNOS media driver (s5p)
 - two fixes at the OMAP3 preview driver
 - one fix at the dvb core failure path
 - an include missing (slab.h) at smiapp-core causing compilation
   breakage
 - em28xx was not loading the IR driver driver anymore.

* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (31 commits)
  [media] Revert "[media] V4L: JPEG class documentation corrections"
  [media] s5p-fimc: Add missing FIMC-LITE file operations locking
  [media] omap3isp: preview: Fix contrast and brightness handling
  [media] omap3isp: preview: Fix output size computation depending on input format
  [media] winbond-cir: Initialise timeout, driver_type and allowed_protos
  [media] winbond-cir: Fix txandrx module info
  [media] cx23885: Silence unknown command warnings
  [media] cx23885: add support for HVR-1255 analog (cx23888 variant)
  [media] cx23885: make analog support work for HVR_1250 (cx23885 variant)
  [media] cx25840: fix vsrc/hsrc usage on cx23888 designs
  [media] cx25840: fix regression in HVR-1800 analog audio
  [media] cx25840: fix regression in analog support hue/saturation controls
  [media] cx25840: fix regression in HVR-1800 analog support
  [media] s5p-mfc: Fixed setup of custom controls in decoder and encoder
  [media] cx231xx: don't DMA to random addresses
  [media] em28xx: fix em28xx-rc load
  [media] dvb-core: Release semaphore on error path dvb_register_device()
  [media] s5p-fimc: Stop media entity pipeline if fimc_pipeline_validate fails
  [media] s5p-fimc: Fix compiler warning in fimc-lite.c
  [media] s5p-fimc: media_entity_pipeline_start() may fail
  ...
2012-07-13 10:29:41 -07:00
Linus Torvalds
36ec9fbfe7 Late MTD fixes for 3.5:
- fix 'sparse warning fix' regression which totally breaks MXC NAND
  - fix GPMI NAND regression when used with UBI
  - update/correct sysfs documentation for new 'bitflip_threshold' field
  - fix nandsim build failure
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Merge tag 'for-linus-20120712' of git://git.infradead.org/linux-mtd

Pull late MTD fixes from David Woodhouse:
 - fix 'sparse warning fix' regression which totally breaks MXC NAND
 - fix GPMI NAND regression when used with UBI
 - update/correct sysfs documentation for new 'bitflip_threshold' field
 - fix nandsim build failure

* tag 'for-linus-20120712' of git://git.infradead.org/linux-mtd:
  mtd: nandsim: don't open code a do_div helper
  mtd: ABI documentation: clarification of bitflip_threshold
  mtd: gpmi-nand: fix read page when reading to vmalloced area
  mtd: mxc_nand: use 32bit copy functions
2012-07-13 09:56:26 -07:00
Andy Lutomirski
c540521bba security: Minor improvements to no_new_privs documentation
The documentation didn't actually mention how to enable no_new_privs.
This also adds a note about possible interactions between
no_new_privs and LSMs (i.e. why teaching systemd to set no_new_privs
is not necessarily a good idea), and it references the new docs
from include/linux/prctl.h.

Suggested-by: Rob Landley <rob@landley.net>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-07-08 00:25:48 +10:00
Sylwester Nawrocki
ec3ed85f92 [media] Revert "[media] V4L: JPEG class documentation corrections"
This reverts commit feed0258e1, as the same issues
are already covered in another version of that patch that
was also applied (579e92ffac).

Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-07-07 00:12:50 -03:00
Mike Dunn
021796b892 mtd: ABI documentation: clarification of bitflip_threshold
The -EUCLEAN return value applies to mtd_read_oob() as well as mtd_read(), but
only mtd_read() was mentioned in the blurd on bitflip_threshold in the ABI
documentation.

Signed-off-by: Mike Dunn <mikedunn@newsguy.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
2012-07-06 15:10:06 +01:00
Linus Torvalds
6bc51545da Merge git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM fix from Marcelo Tosatti:
 "Memory leak and oops on the x86 mmu code, and sanitization of the
  KVM_IRQFD ioctl."

* git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: MMU: fix shrinking page from the empty mmu
  KVM: fix fault page leak
  KVM: Sanitize KVM_IRQFD flags
  KVM: Add missing KVM_IRQFD API documentation
  KVM: Pass kvm_irqfd to functions
2012-07-05 13:16:21 -07:00
Linus Torvalds
62ad64498a Merge branch 'fixes-for-grant' of git://sources.calxeda.com/kernel/linux
Pull DT fixes from Rob Herring:
 "Mainly some documentation updates and 2 fixes:

   - An export symbol fix for of_platform_populate from Stephen W.
   - A fix for the order compatible entries are matched to ensure the
     first compatible string is matched when there are multiple matches."

Normally these would go through Grant Likely (thus the "fixes-for-grant"
branch name), but Grant is in the middle of moving to Scotland, and is
practically offline until sometime in August. So pull directly from Rob.

* 'fixes-for-grant' of git://sources.calxeda.com/kernel/linux:
  of: match by compatible property first
  dt: mc13xxx.txt: Fix gpio number assignment
  dt: fsl-fec.txt: Fix gpio number assignment
  dt: fsl-mma8450.txt: Add missing 'reg' description
  dt: fsl-imx-esdhc.txt: Fix gpio number assignment
  dt: fsl-imx-cspi.txt: Fix comment about GPIOs used for chip selects
  of: Add Avionic Design vendor prefix
  of: export of_platform_populate()
2012-07-05 11:53:47 -07:00
Linus Torvalds
a3da2c6913 Merge branch 'for-linus' of git://git.kernel.dk/linux-block
Pull block bits from Jens Axboe:
 "As vacation is coming up, thought I'd better get rid of my pending
  changes in my for-linus branch for this iteration.  It contains:

   - Two patches for mtip32xx.  Killing a non-compliant sysfs interface
     and moving it to debugfs, where it belongs.

   - A few patches from Asias.  Two legit bug fixes, and one killing an
     interface that is no longer in use.

   - A patch from Jan, making the annoying partition ioctl warning a bit
     less annoying, by restricting it to !CAP_SYS_RAWIO only.

   - Three bug fixes for drbd from Lars Ellenberg.

   - A fix for an old regression for umem, it hasn't really worked since
     the plugging scheme was changed in 3.0.

   - A few fixes from Tejun.

   - A splice fix from Eric Dumazet, fixing an issue with pipe
     resizing."

* 'for-linus' of git://git.kernel.dk/linux-block:
  scsi: Silence unnecessary warnings about ioctl to partition
  block: Drop dead function blk_abort_queue()
  block: Mitigate lock unbalance caused by lock switching
  block: Avoid missed wakeup in request waitqueue
  umem: fix up unplugging
  splice: fix racy pipe->buffers uses
  drbd: fix null pointer dereference with on-congestion policy when diskless
  drbd: fix list corruption by failing but already aborted reads
  drbd: fix access of unallocated pages and kernel panic
  xen/blkfront: Add WARN to deal with misbehaving backends.
  blkcg: drop local variable @q from blkg_destroy()
  mtip32xx: Create debugfs entries for troubleshooting
  mtip32xx: Remove 'registers' and 'flags' from sysfs
  blkcg: fix blkg_alloc() failure path
  block: blkcg_policy_cfq shouldn't be used if !CONFIG_CFQ_GROUP_IOSCHED
  block: fix return value on cfq_init() failure
  mtip32xx: Remove version.h header file inclusion
  xen/blkback: Copy id field when doing BLKIF_DISCARD.
2012-07-03 15:45:10 -07:00
Linus Torvalds
3492ee7274 Four minor thin provisioning fixes and correct and update dm-verity
documentation.
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Merge tag 'dm-3.5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm

Pull device-mapper fixes from Alasdair G Kergon:
 "Four minor thin provisioning fixes and correct and update dm-verity
  documentation."

* tag 'dm-3.5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm:
  dm: verity fix documentation
  dm persistent data: fix allocation failure in space map checker init
  dm persistent data: handle space map checker creation failure
  dm persistent data: fix shadow_info_leak on dm_tm_destroy
  dm thin: commit metadata before creating metadata snapshot
2012-07-03 11:08:16 -07:00
Milan Broz
18068bdd5f dm: verity fix documentation
Veritysetup is now part of cryptsetup package.
Remove on-disk header description (which is not parsed in kernel)
and point users to cryptsetup where it the format is documented.
Mention units for block size paramaters.
Fix target line specification and dmsetup parameters.

Signed-off-by: Milan Broz <mbroz@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-07-03 12:55:41 +01:00
Andy Lutomirski
09b243577b security: document no_new_privs
Document no_new_privs.

Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: James Morris <james.l.morris@oracle.com>
2012-07-03 12:35:36 +10:00
Alex Williamson
f36992e312 KVM: Add missing KVM_IRQFD API documentation
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-07-02 21:10:30 -03:00
Linus Torvalds
21f27291f5 Driver Core fixes for 3.5-rc5
Here is a number of printk() fixes, specifically a few reported by the
 crazy blog program that ships in SUSE releases (that's "boot log" and
 not "web log", it predates the general "blog" terminology by many
 years), and the restoration of the continuation line functionality
 reported by Stephen and others.  Yes, the changes seem a bit big this
 late in the cycle, but I've been beating on them for a while now, and
 Stephen has even optimized it a bit, so all looks good to me.
 
 The other change in here is a Documentation update for the stable kernel
 rules describing how some distro patches should be backported, to
 hopefully drive a bit more response from the distros to the stable
 kernel releases.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver Core fixes from Greg Kroah-Hartman:
 "Here is a number of printk() fixes, specifically a few reported by the
  crazy blog program that ships in SUSE releases (that's "boot log" and
  not "web log", it predates the general "blog" terminology by many
  years), and the restoration of the continuation line functionality
  reported by Stephen and others.  Yes, the changes seem a bit big this
  late in the cycle, but I've been beating on them for a while now, and
  Stephen has even optimized it a bit, so all looks good to me.

  The other change in here is a Documentation update for the stable
  kernel rules describing how some distro patches should be backported,
  to hopefully drive a bit more response from the distros to the stable
  kernel releases.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'driver-core-3.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  printk: Optimize if statement logic where newline exists
  printk: flush continuation lines immediately to console
  syslog: fill buffer with more than a single message for SYSLOG_ACTION_READ
  Revert "printk: return -EINVAL if the message len is bigger than the buf size"
  printk: fix regression in SYSLOG_ACTION_CLEAR
  stable: Allow merging of backports for serious user-visible performance issues
2012-06-30 10:11:24 -07:00
Linus Torvalds
aace99e57c Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media fixes from Mauro Carvalho Chehab.

Trivial conflict due to new USB HID ID's being added next to each other
(Baanto vs Axentia).

* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (44 commits)
  [media] smia: Fix compile failures
  [media]  Fix VIDIOC_DQEVENT docbook entry
  [media] s5p-fimc: Fix control creation function
  [media] s5p-mfc: Fix checkpatch error in s5p_mfc_shm.h file
  [media] s5p-mfc: Fix setting controls
  [media] v4l/s5p-mfc: added image size align in VIDIOC_TRY_FMT
  [media] v4l/s5p-mfc: corrected encoder v4l control definitions
  [media] v4l: mem2mem_testdev: Fix race conditions in driver
  [media] s5p-mfc: Bug fix of timestamp/timecode copy mechanism
  [media] cxd2820r: Fix an incorrect modulation type bitmask
  [media] em28xx: Show a warning if the board does not support remote controls
  [media] em28xx: Add remote control support for Terratec's Cinergy HTC Stick HD
  [media] USB: Staging: media: lirc: initialize spinlocks before usage
  [media] Revert "[media] media: mx2_camera: Fix mbus format handling"
  [media] bw-qcam: driver and pixfmt documentation fixes
  [media] cx88: fix firmware load on big-endian systems
  [media] cx18: support big-endian systems
  [media] ivtv: fix support for big-endian systems
  [media] tuner-core: return the frequency range of the correct tuner
  [media] v4l2-dev.c: fix g_parm regression in determine_valid_ioctls()
  ...
2012-06-25 14:53:09 -07:00
Mel Gorman
eb3979f64d stable: Allow merging of backports for serious user-visible performance issues
Distribution kernel maintainers routinely backport fixes for users that
were deemed important but not "something critical" as defined by the
rules. To users of these kernels they are very serious and failing to fix
them reduces the value of -stable.

The problem is that the patches fixing these issues are often subtle and
prone to regressions in other ways and need greater care and attention.
To combat this, these "serious" backports should have a higher barrier
to entry.

This patch relaxes the rules to allow a distribution maintainer to merge
to -stable a backported patch or small series that fixes a "serious"
user-visible performance issue. They should include additional information on
the user-visible bug affected and a link to the bugzilla entry if available.
The same rules about the patch being already in mainline still apply.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-25 12:11:58 -07:00
Linus Torvalds
bc259adc9b staging tree fixes for 3.5-rc4
Here are a number of small fixes for the drivers/staging tree, as well as iio
 and pstore drivers (which came from the staging tree in the 3.5-rc1 merge).
 All of these are tiny, but resolve issues that people have been reporting.
 
 There's also a documentation update to reflect what the iio drivers really are
 doing, which is good to get straightened out.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'staging-3.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging tree fixes from Greg Kroah-Hartman:
 "Here are a number of small fixes for the drivers/staging tree, as well
  as iio and pstore drivers (which came from the staging tree in the
  3.5-rc1 merge).  All of these are tiny, but resolve issues that people
  have been reporting.

  There's also a documentation update to reflect what the iio drivers
  really are doing, which is good to get straightened out.

  Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>"

* tag 'staging-3.5-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: r8712u: Add new USB IDs
  staging: gdm72xx: Release netlink socket properly
  iio: drop wrong reference from Kconfig
  pstore/inode: Make pstore_fill_super() static
  pstore/ram: Should zap persistent zone on unlink
  pstore/ram_core: Factor persistent_ram_zap() out of post_init()
  pstore/ram_core: Do not reset restored zone's position and size
  pstore/ram: Should update old dmesg buffer before reading
  staging:iio:ad7298: Fix linker error due to missing IIO kfifo buffer
  Revert "staging: usbip: bugfix for stack corruption on 64-bit architectures"
  staging: usbip: bugfix for stack corruption on 64-bit architectures
  staging/comedi: fix build for USB not enabled
  staging: omapdrm: fix crash when freeing bad fb
  staging:iio:ad7606: Re-add missing scale attribute
  iio: Fix potential use after free
  staging:iio: remove num_interrupt_lines from documentation
  iio: documentation: Add out_altvoltage and friends
2012-06-20 15:15:03 -07:00
Linus Torvalds
a2a2609c97 Merge branch 'akpm' (Andrew's patch-bomb)
* emailed from Andrew Morton <akpm@linux-foundation.org>: (21 patches)
  mm/memblock: fix overlapping allocation when doubling reserved array
  c/r: prctl: Move PR_GET_TID_ADDRESS to a proper place
  pidns: find_new_reaper() can no longer switch to init_pid_ns.child_reaper
  pidns: guarantee that the pidns init will be the last pidns process reaped
  fault-inject: avoid call to random32() if fault injection is disabled
  Viresh has moved
  get_maintainer: Fix --help warning
  mm/memory.c: fix kernel-doc warnings
  mm: fix kernel-doc warnings
  mm: correctly synchronize rss-counters at exit/exec
  mm, thp: print useful information when mmap_sem is unlocked in zap_pmd_range
  h8300: use the declarations provided by <asm/sections.h>
  h8300: fix use of extinct _sbss and _ebss
  xtensa: use the declarations provided by <asm/sections.h>
  xtensa: use "test -e" instead of bashism "test -a"
  xtensa: replace xtensa-specific _f{data,text} by _s{data,text}
  memcg: fix use_hierarchy css_is_ancestor oops regression
  mm, oom: fix and cleanup oom score calculations
  nilfs2: ensure proper cache clearing for gc-inodes
  thp: avoid atomic64_read in pmd_read_atomic for 32bit PAE
  ...
2012-06-20 14:41:57 -07:00
Viresh Kumar
10d8935f46 Viresh has moved
viresh.kumar@st.com email-id doesn't exist anymore as I have left the
company.  Replace ST's id with viresh.linux@gmail.com.

It also updates .mailmap file to fix address for 'git shortlog'

Signed-off-by: Viresh Kumar <viresh.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-20 14:39:36 -07:00
Hans Verkuil
2bece307c9 [media] Fix VIDIOC_DQEVENT docbook entry
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Sakari Ailus <sakari.ailus@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-06-18 19:50:07 -03:00
Guenter Roeck
813441f16e hwmon: (coretemp) Document TjMax for 3rd generation i5/i7 processors
Tjmax values from Intel datasheets.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-06-17 18:05:06 +02:00
Guenter Roeck
5592906f8b hwmon: (coretemp) Add support for Atom D2000 and N2000 series CPU models
Document the Atom series D2000 and N2000 (Cedar Trail) as being supported.
List and set TjMax for those series.

Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: "R, Durgadoss" <durgadoss.r@intel.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
2012-06-17 18:05:05 +02:00
Jean Delvare
fcc14ac1a8 hwmon: (coretemp) Improve support of recent Atom CPU models
Document the new Atom series (Tunnel Creek and Medfield) as being
supported, and list TjMax for the Atom E600 series.

Also enable the Atom tjmax heuristic for these Atom CPU models.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Reviewed-by: Guenter Roeck <guenter.roeck@ericsson.com>
Cc: Alexander Stein <alexander.stein@systec-electronic.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: "R, Durgadoss" <durgadoss.r@intel.com>
2012-06-17 18:05:05 +02:00
Linus Torvalds
fea7c7830d Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David S. Miller:

This has the fix for the wireless issues I ran into the other week as
well as:

 1) Fix CAN c_can driver transmit handling resulting in BUG check
    triggers, from AnilKumar Ch.

 2) Fix packet drop monitor sleeping in atomic context, from Eric
    Dumazet.

 3) Fix mv643xx_eth driver build regression, from Andrew Lunn.

 4) Inetpeer freeing needs an RCU grace period in order to avoid races
    during tree invalidation.  From Eric Dumazet.

 5) Fix endianness bugs in xt_HMARK netfilter module, from Hans
    Schillstrom.

 6) Add proper module refcounting to l2tp_eth to avoid crash on module
    unload, from Eric Dumazet.

 7) Fix truncation of neighbour entry dumps due to logic errors in
    neigh_dump_info() and friends, from Eric Dumazet.

 8) The conversion of fib6_age() to dst_neigh_lookup() accidently
    reversed the logic of a flags test, fix from Thomas Graf.

 9) Fix checksum configuration in newer sky2 chips, from Stephen
    Hemminger.

10) Revert BQL support in NIU driver, doesn't work.

11) l2tp_ip_sendmsg() illegally uses a route without a proper reference.
    From Eric Dumazet.

12) be2net driver references an SKB after it's potentially been freed,
    also from Eric Dumazet.

13) Fix RCU stalls in dummy net driver init.  Also from Eric Dumazet.

14) lpc_eth has several bugs in it's transmit engine leading to packet
    leaks and improper queue wakes, from Eric Dumazet.

15) Apply short DMA workaround to more tg3 chips, from Matt Carlson.

16) Add tilegx network driver.

17) Bonding queue mapping for a packet can get corrupted, fix from Eric
    Dumazet.

18) Fix bug in netpoll_send_udp() SKB management that can leave garbage
    in the payload in certain situations.  From Eric Dumazet.

19) bnx2x driver interprets chip RX checksum offload incorrectly in
    encapsulation situations.  Fix from Eric Dumazet.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (75 commits)
  bnx2x: fix checksum validation
  netpoll: fix netpoll_send_udp() bugs
  bonding: Fix corrupted queue_mapping
  bonding:record primary when modify it via sysfs
  tilegx network driver: initial support
  tg3: Apply short DMA frag workaround to 5906
  net: stmmac: Fix clock en-/disable calls
  lpc_eth: fix tx completion
  lpc_eth: add missing ndo_change_mtu()
  dummy: fix rcu_sched self-detected stalls
  net: Reorder initialization in ip_route_output to fix gcc warning
  virtio-net: fix a race on 32bit arches
  r8169: avoid NAPI scheduling delay.
  net: Make linux/tcp.h C++ friendly (trivial)
  netdev: fix drivers/net/phy/ kernel-doc warnings
  net/core: fix kernel-doc warnings
  be2net: fix a race in be_xmit()
  l2tp: fix a race in l2tp_ip_sendmsg()
  mac80211: add back channel change flag
  NFC: Fix possible NULL ptr deref when getting the name of a socket
  ...
2012-06-14 15:33:55 +03:00
Fabio Estevam
d44115f28e dt: mc13xxx.txt: Fix gpio number assignment
Fix gpio number assignment, so that it can match the number stated in the comment.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2012-06-13 13:34:54 -05:00
Fabio Estevam
af634df194 dt: fsl-fec.txt: Fix gpio number assignment
Fix gpio number assignment, so that it can match the number stated in the comment.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2012-06-13 13:34:54 -05:00
Fabio Estevam
d7858de945 dt: fsl-mma8450.txt: Add missing 'reg' description
Add missing 'reg' description.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
----
 .../devicetree/bindings/input/fsl-mma8450.txt      |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2012-06-13 13:34:41 -05:00
Fabio Estevam
06693fcd57 dt: fsl-imx-esdhc.txt: Fix gpio number assignment
Fix gpio number assignment, so that it can match the number stated in the comment.

Cc:
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2012-06-13 13:34:40 -05:00
Fabio Estevam
37797d5f2e dt: fsl-imx-cspi.txt: Fix comment about GPIOs used for chip selects
The gpio numbers does not match the comment.

Fix the comments for GPIOs used for chip selects.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2012-06-13 13:34:39 -05:00
Thierry Reding
ae2a7d2008 of: Add Avionic Design vendor prefix
This commit adds a device tree vendor prefix for Avionic Design GmbH.

Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: devicetree-discuss@lists.ozlabs.org
Cc: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>
2012-06-13 13:34:39 -05:00
Hans Verkuil
de87897af0 [media] bw-qcam: driver and pixfmt documentation fixes
Fix the documentation of the Y4 and Y6 formats.
Fix a poll() issue, add support for enum_frmsizes, set the proper
parent device and fix a few compliance issues.

Tested with an actual Connectix B&W parallel port webcam, both on a
little-endian and a big-endian platform. This driver has never been
so good, doing 320x240 at 1 frame per second :-)

I know, nobody cares, but still it is cool that linux can still support
this old webcam.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-06-11 18:16:09 -03:00
Hans Verkuil
87736df240 [media] V4L2 spec fix
Two small docbook fixes:

- prepare-buf was not positioned in alphabetical order, moved to the right place.
- the format field in create_bufs had the wrong type in the documentation

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-06-11 15:50:47 -03:00
Sakari Ailus
af03891f61 [media] v4l: Correct create_bufs documentation
Patch id 6016af82ea ("[media] v4l2: use __u32
rather than enums in ioctl() structs") unintentionally changes the type of
the format field in struct v4l2_create_buffers from struct v4l2_format to
__u32. Revert that change.

Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-06-11 15:15:33 -03:00
Giuseppe CAVALLARO
3d2377144c stmmac: update driver's doc
Fixed the driver's documentation that was obsolete and didn't
report new platform fields (recently added).

Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-06 09:34:56 -07:00
Linus Torvalds
690efa08e2 Merge branch 'i2c-embedded/for-current' of git://git.pengutronix.de/git/wsa/linux
Pull embedded i2c update from Wolfram Sang:
 "This only contains one new driver which had multiple dependencies
  (pinctrl, i2c-mux-rework, new devm_* functions), so I decided to wait
  for rc1.  Plus, it had to wait a little for the ack of a devicetree
  maintainer since the bindings were not trivial enough for me to pass
  through.

  So, given that, I hope there is still something like the "new driver
  rule", so we could have the driver in 3.5 and people can start using
  it.  That would make merging support for some boards easier for 3.6
  since the dependency on this driver is gone then."

* 'i2c-embedded/for-current' of git://git.pengutronix.de/git/wsa/linux:
  i2c: Add generic I2C multiplexer using pinctrl API
2012-06-05 10:55:31 -07:00
Asai Thambi S P
7412ff139d mtip32xx: Remove 'registers' and 'flags' from sysfs
This patch removes entries 'registers' and 'flags' from sysfs. Updated ABI file
to reflect this change.

Reported-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Asai Thambi S P <asamymuthupa@micron.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-06-05 09:13:48 +02:00
Michael Hennerich
d802bf6f09 iio: documentation: Add out_altvoltage and friends
Continuous frequency/clock generating devices, such as DDSs or PLLs
should use out_altvoltage.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-04 21:15:31 -07:00
Linus Torvalds
a3fe778c78 Frontswap provides a "transcendent memory" interface for swap pages.
In some environments, dramatic performance savings may be obtained because
 swapped pages are saved in RAM (or a RAM-like device) instead of a swap disk.
 This tag provides the basic infrastructure along with some changes to the
 existing backends.
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Merge tag 'stable/frontswap.v16-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/mm

Pull frontswap feature from Konrad Rzeszutek Wilk:
 "Frontswap provides a "transcendent memory" interface for swap pages.
  In some environments, dramatic performance savings may be obtained
  because swapped pages are saved in RAM (or a RAM-like device) instead
  of a swap disk.  This tag provides the basic infrastructure along with
  some changes to the existing backends."

Fix up trivial conflict in mm/Makefile due to removal of swap token code
changing a line next to the new frontswap entry.

This pull request came in before the merge window even opened, it got
delayed to after the merge window by me just wanting to make sure it had
actual users.  Apparently IBM is using this on their embedded side, and
Jan Beulich says that it's already made available for SLES and OpenSUSE
users.

Also acked by Rik van Riel, and Konrad points to other people liking it
too.  So in it goes.

By Dan Magenheimer (4) and Konrad Rzeszutek Wilk (2)
via Konrad Rzeszutek Wilk
* tag 'stable/frontswap.v16-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/mm:
  frontswap: s/put_page/store/g s/get_page/load
  MAINTAINER: Add myself for the frontswap API
  mm: frontswap: config and doc files
  mm: frontswap: core frontswap functionality
  mm: frontswap: core swap subsystem hooks and headers
  mm: frontswap: add frontswap header file
2012-06-04 12:28:45 -07:00
Linus Torvalds
c22072bdf0 Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
 "The clocksource driver is pure hardware enablement and the skew option
  is default off, well tested and non dangerous."

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tick: Move skew_tick option into the HIGH_RES_TIMER section
  clocksource: em_sti: Add DT support
  clocksource: em_sti: Emma Mobile STI driver
  clockevents: Make clockevents_config() a global symbol
  tick: Add tick skew boot option
2012-06-04 11:25:31 -07:00
Stephen Warren
ae58d1e406 i2c: Add generic I2C multiplexer using pinctrl API
This is useful for SoCs whose I2C module's signals can be routed to
different sets of pins at run-time, using the pinctrl API.

                                 +-----+  +-----+
                                 | dev |  | dev |
    +------------------------+   +-----+  +-----+
    | SoC                    |      |        |
    |                   /----|------+--------+
    |   +---+   +------+     | child bus A, on first set of pins
    |   |I2C|---|Pinmux|     |
    |   +---+   +------+     | child bus B, on second set of pins
    |                   \----|------+--------+--------+
    |                        |      |        |        |
    +------------------------+  +-----+  +-----+  +-----+
                                | dev |  | dev |  | dev |
                                +-----+  +-----+  +-----+

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-06-04 16:49:43 +02:00
Linus Torvalds
912afc3616 Improve multipath's retrying mechanism in some defined circumstances
and provide a simple reserve/release mechanism for userspace tools to
 access thin provisioning metadata while the pool is in use.
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Merge tag 'dm-3.5-changes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm

Pull device-mapper updates from Alasdair G Kergon:
 "Improve multipath's retrying mechanism in some defined circumstances
  and provide a simple reserve/release mechanism for userspace tools to
  access thin provisioning metadata while the pool is in use."

* tag 'dm-3.5-changes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-dm:
  dm thin: provide userspace access to pool metadata
  dm thin: use slab mempools
  dm mpath: allow ioctls to trigger pg init
  dm mpath: delay retry of bypassed pg
  dm mpath: reduce size of struct multipath
2012-06-02 17:39:40 -07:00
Joe Thornber
cc8394d86f dm thin: provide userspace access to pool metadata
This patch implements two new messages that can be sent to the thin
pool target allowing it to take a snapshot of the _metadata_.  This,
read-only snapshot can be accessed by userland, concurrently with the
live target.

Only one metadata snapshot can be held at a time.  The pool's status
line will give the block location for the current msnap.

Since version 0.1.5 of the userland thin provisioning tools, the
thin_dump program displays the msnap as follows:

    thin_dump -m <msnap root> <metadata dev>

Available here: https://github.com/jthornber/thin-provisioning-tools

Now that userland can access the metadata we can do various things
that have traditionally been kernel side tasks:

     i) Incremental backups.

     By using metadata snapshots we can work out what blocks have
     changed over time.  Combined with data snapshots we can ensure
     the data doesn't change while we back it up.

     A short proof of concept script can be found here:

     https://github.com/jthornber/thinp-test-suite/blob/master/incremental_backup_example.rb

     ii) Migration of thin devices from one pool to another.

     iii) Merging snapshots back into an external origin.

     iv) Asyncronous replication.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2012-06-03 00:30:01 +01:00