linux-stable.git, branch v4.4.166

Linux 4.4.166

2018-12-01T08:46:41+00:00

drm/ast: Remove existing framebuffers before loading driver

2018-12-01T08:46:41+00:00

commit 5478ad10e7850ce3d8b7056db05ddfa3c9ddad9a upstream.

If vesafb attaches to the AST device, it configures the framebuffer memory
for uncached access by default. When ast.ko later tries to attach itself to
the device, it wants to use write-combining on the framebuffer memory, but
vesefb's existing configuration for uncached access takes precedence. This
results in reduced performance.

Removing the framebuffer's configuration before loding the AST driver fixes
the problem. Other DRM drivers already contain equivalent code.

Link: https://bugzilla.opensuse.org/show_bug.cgi?id=1112963
Signed-off-by: Thomas Zimmermann 
Cc: 
Tested-by: Y.C. Chen 
Reviewed-by: Jean Delvare 
Tested-by: Jean Delvare 
Signed-off-by: Dave Airlie 
Signed-off-by: Greg Kroah-Hartman

s390/mm: Check for valid vma before zapping in gmap_discard

2018-12-01T08:46:41+00:00

commit 1843abd03250115af6cec0892683e70cf2297c25 upstream.

Userspace could have munmapped the area before doing unmapping from
the gmap. This would leave us with a valid vmaddr, but an invalid vma
from which we would try to zap memory.

Let's check before using the vma.

Fixes: 1e133ab296f3 ("s390/mm: split arch/s390/mm/pgtable.c")
Signed-off-by: Janosch Frank 
Reviewed-by: David Hildenbrand 
Reported-by: Dan Carpenter 
Message-Id: <20180816082432.78828-1-frankja@linux.ibm.com>
Signed-off-by: Janosch Frank 
Signed-off-by: Greg Kroah-Hartman

namei: allow restricted O_CREAT of FIFOs and regular files

2018-12-01T08:46:41+00:00

commit 30aba6656f61ed44cba445a3c0d38b296fa9e8f5 upstream.

Disallows open of FIFOs or regular files not owned by the user in world
writable sticky directories, unless the owner is the same as that of the
directory or the file is opened without the O_CREAT flag.  The purpose
is to make data spoofing attacks harder.  This protection can be turned
on and off separately for FIFOs and regular files via sysctl, just like
the symlinks/hardlinks protection.  This patch is based on Openwall's
"HARDEN_FIFO" feature by Solar Designer.

This is a brief list of old vulnerabilities that could have been prevented
by this feature, some of them even allow for privilege escalation:

CVE-2000-1134
CVE-2007-3852
CVE-2008-0525
CVE-2009-0416
CVE-2011-4834
CVE-2015-1838
CVE-2015-7442
CVE-2016-7489

This list is not meant to be complete.  It's difficult to track down all
vulnerabilities of this kind because they were often reported without any
mention of this particular attack vector.  In fact, before
hardlinks/symlinks restrictions, fifos/regular files weren't the favorite
vehicle to exploit them.

[s.mesoraca16@gmail.com: fix bug reported by Dan Carpenter]
  Link: https://lkml.kernel.org/r/20180426081456.GA7060@mwanda
  Link: http://lkml.kernel.org/r/1524829819-11275-1-git-send-email-s.mesoraca16@gmail.com
[keescook@chromium.org: drop pr_warn_ratelimited() in favor of audit changes in the future]
[keescook@chromium.org: adjust commit subjet]
Link: http://lkml.kernel.org/r/20180416175918.GA13494@beast
Signed-off-by: Salvatore Mesoraca 
Signed-off-by: Kees Cook 
Suggested-by: Solar Designer 
Suggested-by: Kees Cook 
Cc: Al Viro 
Cc: Dan Carpenter 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Cc: Loic 
Signed-off-by: Greg Kroah-Hartman

sched/core: Allow __sched_setscheduler() in interrupts when PI is not used

2018-12-01T08:46:41+00:00

commit 896bbb2522587e3b8eb2a0d204d43ccc1042a00d upstream.

When priority inheritance was added back in 2.6.18 to sched_setscheduler(), it
added a path to taking an rt-mutex wait_lock, which is not IRQ safe. As PI
is not a common occurrence, lockdep will likely never trigger if
sched_setscheduler was called from interrupt context. A BUG_ON() was added
to trigger if __sched_setscheduler() was ever called from interrupt context
because there was a possibility to take the wait_lock.

Today the wait_lock is irq safe, but the path to taking it in
sched_setscheduler() is the same as the path to taking it from normal
context. The wait_lock is taken with raw_spin_lock_irq() and released with
raw_spin_unlock_irq() which will indiscriminately enable interrupts,
which would be bad in interrupt context.

The problem is that normalize_rt_tasks, which is called by triggering the
sysrq nice-all-RT-tasks was changed to call __sched_setscheduler(), and this
is done from interrupt context!

Now __sched_setscheduler() takes a "pi" parameter that is used to know if
the priority inheritance should be called or not. As the BUG_ON() only cares
about calling the PI code, it should only bug if called from interrupt
context with the "pi" parameter set to true.

Reported-by: Laurent Dufour 
Tested-by: Laurent Dufour 
Signed-off-by: Steven Rostedt (VMware) 
Signed-off-by: Peter Zijlstra (Intel) 
Cc: Andrew Morton 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Fixes: dbc7f069b93a ("sched: Use replace normalize_task() with __sched_setscheduler()")
Link: http://lkml.kernel.org/r/20170308124654.10e598f2@gandalf.local.home
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

btrfs: Ensure btrfs_trim_fs can trim the whole filesystem

2018-12-01T08:46:41+00:00

commit 6ba9fc8e628becf0e3ec94083450d089b0dec5f5 upstream.

[BUG]
fstrim on some btrfs only trims the unallocated space, not trimming any
space in existing block groups.

[CAUSE]
Before fstrim_range passed to btrfs_trim_fs(), it gets truncated to
range [0, super->total_bytes).  So later btrfs_trim_fs() will only be
able to trim block groups in range [0, super->total_bytes).

While for btrfs, any bytenr aligned to sectorsize is valid, since btrfs
uses its logical address space, there is nothing limiting the location
where we put block groups.

For filesystem with frequent balance, it's quite easy to relocate all
block groups and bytenr of block groups will start beyond
super->total_bytes.

In that case, btrfs will not trim existing block groups.

[FIX]
Just remove the truncation in btrfs_ioctl_fitrim(), so btrfs_trim_fs()
can get the unmodified range, which is normally set to [0, U64_MAX].

Reported-by: Chris Murphy 
Fixes: f4c697e6406d ("btrfs: return EINVAL if start > total_bytes in fitrim ioctl")
CC:  # v4.4+
Signed-off-by: Qu Wenruo 
Reviewed-by: Nikolay Borisov 
Reviewed-by: David Sterba 
Signed-off-by: David Sterba 
Signed-off-by: Greg Kroah-Hartman

usb: xhci: fix uninitialized completion when USB3 port got wrong status

2018-12-01T08:46:41+00:00

commit 958c0bd86075d4ef1c936998deefe1947e539240 upstream.

Realtek USB3.0 Card Reader [0bda:0328] reports wrong port status on
Cannon lake PCH USB3.1 xHCI [8086:a36d] after resume from S3,
after clear port reset it works fine.

Since this device is registered on USB3 roothub at boot,
when port status reports not superspeed, xhci_get_port_status will call
an uninitialized completion in bus_state[0].
Kernel will hang because of NULL pointer.

Restrict the USB2 resume status check in USB2 roothub to fix hang issue.

Cc: stable@vger.kernel.org
Signed-off-by: Aaron Ma 
Signed-off-by: Mathias Nyman 
Signed-off-by: Greg Kroah-Hartman

tty: wipe buffer if not echoing data

2018-12-01T08:46:41+00:00

commit b97b3d9fb57860a60592859e332de7759fd54c2e upstream.

If we are not echoing the data to userspace or the console is in icanon
mode, then perhaps it is a "secret" so we should wipe it once we are
done with it.

This mirrors the logic that the audit code has.

Reported-by: aszlig 
Tested-by: Milan Broz 
Tested-by: Daniel Zatovic 
Tested-by: aszlig 
Cc: Willy Tarreau 
Signed-off-by: Greg Kroah-Hartman

tty: wipe buffer.

2018-12-01T08:46:40+00:00

commit c9a8e5fce009e3c601a43c49ea9dbcb25d1ffac5 upstream.

After we are done with the tty buffer, zero it out.

Reported-by: aszlig 
Tested-by: Milan Broz 
Tested-by: Daniel Zatovic 
Tested-by: aszlig 
Cc: Willy Tarreau 
Signed-off-by: Greg Kroah-Hartman

iwlwifi: mvm: fix regulatory domain update when the firmware starts

2018-12-01T08:46:40+00:00

commit 82715ac71e6b94a2c2136e31f3a8e6748e33aa8c upstream.

When the firmware starts, it doesn't have any regulatory
information, hence it uses the world wide limitations. The
driver can feed the firmware with previous knowledge that
was kept in the driver, but the firmware may still not
update its internal tables.

This happens when we start a BSS interface, and then the
firmware can change the regulatory tables based on our
location and it'll use more lenient, location specific
rules. Then, if the firmware is shut down (when the
interface is brought down), and then an AP interface is
created, the firmware will forget the country specific
rules.

The host will think that we are in a certain country that
may allow channels and will try to teach the firmware about
our location, but the firmware may still not allow to drop
the world wide limitations and apply country specific rules
because it was just re-started.

In this case, the firmware will reply with MCC_RESP_ILLEGAL
to the MCC_UPDATE_CMD. In that case, iwlwifi needs to let
the upper layers (cfg80211 / hostapd) know that the channel
list they know about has been updated.

This fixes https://bugzilla.kernel.org/show_bug.cgi?id=201105

Cc: stable@vger.kernel.org
Signed-off-by: Emmanuel Grumbach 
Signed-off-by: Luca Coelho 
Signed-off-by: Greg Kroah-Hartman