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Pull namespace fixes from Eric Biederman:
"This tree contains 4 fixes.
The first is a fix for a race that can causes oopses under the right
circumstances, and that someone just recently encountered.
Past that are several small trivial correct fixes. A real issue that
was blocking development of an out of tree driver, but does not appear
to have caused any actual problems for in-tree code. A potential
deadlock that was reported by lockdep. And a deadlock people have
experienced and took the time to track down caused by a cleanup that
removed the code to drop a reference count"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
sysctl: Drop reference added by grab_header in proc_sys_readdir
pid: fix lockdep deadlock warning due to ucount_lock
libfs: Modify mount_pseudo_xattr to be clear it is not a userspace mount
mnt: Protect the mountpoint hashtable with mount_lock
Pull char/misc driver fixes from Greg KH:
"Here are some small char/misc driver fixes for 4.10-rc4 that resolve
some reported issues.
The MEI driver issue resolves a lot of problems that people have been
having, as does the mem driver fix. The other minor fixes resolve
other reported issues.
All of these have been in linux-next for a while"
* tag 'char-misc-4.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
vme: Fix wrong pointer utilization in ca91cx42_slave_get
auxdisplay: fix new ht16k33 build errors
ppdev: don't print a free'd string
extcon: return error code on failure
drivers: char: mem: Fix thinkos in kmem address checks
mei: bus: enable OS version only for SPT and newer
Fixes CVE-2016-9191, proc_sys_readdir doesn't drop reference
added by grab_header when return from !dir_emit_dots path.
It can cause any path called unregister_sysctl_table will
wait forever.
The calltrace of CVE-2016-9191:
[ 5535.960522] Call Trace:
[ 5535.963265] [<ffffffff817cdaaf>] schedule+0x3f/0xa0
[ 5535.968817] [<ffffffff817d33fb>] schedule_timeout+0x3db/0x6f0
[ 5535.975346] [<ffffffff817cf055>] ? wait_for_completion+0x45/0x130
[ 5535.982256] [<ffffffff817cf0d3>] wait_for_completion+0xc3/0x130
[ 5535.988972] [<ffffffff810d1fd0>] ? wake_up_q+0x80/0x80
[ 5535.994804] [<ffffffff8130de64>] drop_sysctl_table+0xc4/0xe0
[ 5536.001227] [<ffffffff8130de17>] drop_sysctl_table+0x77/0xe0
[ 5536.007648] [<ffffffff8130decd>] unregister_sysctl_table+0x4d/0xa0
[ 5536.014654] [<ffffffff8130deff>] unregister_sysctl_table+0x7f/0xa0
[ 5536.021657] [<ffffffff810f57f5>] unregister_sched_domain_sysctl+0x15/0x40
[ 5536.029344] [<ffffffff810d7704>] partition_sched_domains+0x44/0x450
[ 5536.036447] [<ffffffff817d0761>] ? __mutex_unlock_slowpath+0x111/0x1f0
[ 5536.043844] [<ffffffff81167684>] rebuild_sched_domains_locked+0x64/0xb0
[ 5536.051336] [<ffffffff8116789d>] update_flag+0x11d/0x210
[ 5536.057373] [<ffffffff817cf61f>] ? mutex_lock_nested+0x2df/0x450
[ 5536.064186] [<ffffffff81167acb>] ? cpuset_css_offline+0x1b/0x60
[ 5536.070899] [<ffffffff810fce3d>] ? trace_hardirqs_on+0xd/0x10
[ 5536.077420] [<ffffffff817cf61f>] ? mutex_lock_nested+0x2df/0x450
[ 5536.084234] [<ffffffff8115a9f5>] ? css_killed_work_fn+0x25/0x220
[ 5536.091049] [<ffffffff81167ae5>] cpuset_css_offline+0x35/0x60
[ 5536.097571] [<ffffffff8115aa2c>] css_killed_work_fn+0x5c/0x220
[ 5536.104207] [<ffffffff810bc83f>] process_one_work+0x1df/0x710
[ 5536.110736] [<ffffffff810bc7c0>] ? process_one_work+0x160/0x710
[ 5536.117461] [<ffffffff810bce9b>] worker_thread+0x12b/0x4a0
[ 5536.123697] [<ffffffff810bcd70>] ? process_one_work+0x710/0x710
[ 5536.130426] [<ffffffff810c3f7e>] kthread+0xfe/0x120
[ 5536.135991] [<ffffffff817d4baf>] ret_from_fork+0x1f/0x40
[ 5536.142041] [<ffffffff810c3e80>] ? kthread_create_on_node+0x230/0x230
One cgroup maintainer mentioned that "cgroup is trying to offline
a cpuset css, which takes place under cgroup_mutex. The offlining
ends up trying to drain active usages of a sysctl table which apprently
is not happening."
The real reason is that proc_sys_readdir doesn't drop reference added
by grab_header when return from !dir_emit_dots path. So this cpuset
offline path will wait here forever.
See here for details: http://www.openwall.com/lists/oss-security/2016/11/04/13
Fixes: f0c3b5093add ("[readdir] convert procfs")
Cc: stable@vger.kernel.org
Reported-by: CAI Qian <caiqian@redhat.com>
Tested-by: Yang Shukui <yangshukui@huawei.com>
Signed-off-by: Zhou Chengming <zhouchengming1@huawei.com>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Merge tag 'driver-core-4.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core fix from Greg KH:
"Here is a single patch being reverted to remove a feature that was
added in 4.10-rc1 that isn't quite ready for release.
It will be redone as a debugfs file instead of a sysfs file in the
future"
* tag 'driver-core-4.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
Revert "driver core: Add deferred_probe attribute to devices in sysfs"
In ca91cx42_slave_get function, the value pointed by vme_base pointer is
set through:
*vme_base = ioread32(bridge->base + CA91CX42_VSI_BS[i]);
So it must be dereferenced to be used in calculation of pci_base:
*pci_base = (dma_addr_t)*vme_base + pci_offset;
This bug was caught thanks to the following gcc warning:
drivers/vme/bridges/vme_ca91cx42.c: In function ‘ca91cx42_slave_get’:
drivers/vme/bridges/vme_ca91cx42.c:467:14: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
*pci_base = (dma_addr_t)vme_base + pci_offset;
Signed-off-by: Augusto Mecking Caringi <augustocaringi@gmail.com>
Acked-By: Martyn Welch <martyn@welchs.me.uk>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
=========================================================
[ INFO: possible irq lock inversion dependency detected ]
4.10.0-rc2-00024-g4aecec9-dirty #118 Tainted: G W
---------------------------------------------------------
swapper/1/0 just changed the state of lock:
(&(&sighand->siglock)->rlock){-.....}, at: [<ffffffffbd0a1bc6>] __lock_task_sighand+0xb6/0x2c0
but this lock took another, HARDIRQ-unsafe lock in the past:
(ucounts_lock){+.+...}
and interrupts could create inverse lock ordering between them.
other info that might help us debug this:
Chain exists of: &(&sighand->siglock)->rlock --> &(&tty->ctrl_lock)->rlock --> ucounts_lock
Possible interrupt unsafe locking scenario:
CPU0 CPU1
---- ----
lock(ucounts_lock);
local_irq_disable();
lock(&(&sighand->siglock)->rlock);
lock(&(&tty->ctrl_lock)->rlock);
<Interrupt>
lock(&(&sighand->siglock)->rlock);
*** DEADLOCK ***
This patch removes a dependency between rlock and ucount_lock.
Fixes: f333c700c610 ("pidns: Add a limit on the number of pid namespaces")
Cc: stable@vger.kernel.org
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Pull tty/serial fixes from Greg KH:
"Here are some small tty/serial driver fixes for 4.10-rc4 to resolve a
number of reported issues.
Nothing major here at all, one revert of a problematic patch, and some
other tiny bugfixes. Full details are in the shortlog below.
All have been in linux-next with no reported issues"
* tag 'tty-4.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
sysrq: attach sysrq handler correctly for 32-bit kernel
Revert "tty: serial: 8250: add CON_CONSDEV to flags"
Clearing FIFOs in RS485 emulation mode causes subsequent transmits to break
8250_pci: Fix potential use-after-free in error path
tty/serial: atmel: RS485 half duplex w/DMA: enable RX after TX is done
tty/serial: atmel_serial: BUG: stop DMA from transmitting in stop_tx
This reverts commit 6751667a29d6fd64afb9ce30567ad616b68ed789.
Rob Herring objected to it, and a replacement for it will be added using
debugfs in the future.
Cc: Ben Hutchings <ben.hutchings@codethink.co.uk>
Reported-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix build errors caused by selecting incorrect kconfig symbols.
drivers/built-in.o:(.data+0x19cec): undefined reference to `sys_fillrect'
drivers/built-in.o:(.data+0x19cf0): undefined reference to `sys_copyarea'
drivers/built-in.o:(.data+0x19cf4): undefined reference to `sys_imageblit'
Fixes: 31114fa95bdb (auxdisplay: ht16k33: select framebuffer helper modules)
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Miguel Ojeda Sandonis <miguel.ojeda.sandonis@gmail.com>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Acked-by: Robin van der Gracht <robin@protonic.nl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add MS_KERNMOUNT to the flags that are passed.
Use sget_userns and force &init_user_ns instead of calling sget so that
even if called from a weird context the internal filesystem will be
considered to be in the intial user namespace.
Luis Ressel reported that the the failure to pass MS_KERNMOUNT into
mount_pseudo broke his in development graphics driver that uses the
generic drm infrastructure. I am not certain the deriver was bug
free in it's usage of that infrastructure but since
mount_pseudo_xattr can never be triggered by userspace it is clearer
and less error prone, and less problematic for the code to be explicit.
Reported-by: Luis Ressel <aranea@aixah.de>
Tested-by: Luis Ressel <aranea@aixah.de>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Pull USB fixes from Greg KH:
"Here are a few small USB driver fixes for 4.10-rc4 to resolve some
reported issues.
The "largest" here is a number of bugs being fixed in the ch341
usb-serial driver, to hopefully resolve the mess of different devices
floating around that use this driver that have been having problems
with the 4.10-rc1 release.
There's also a tiny musb fix that I missed in the last pull request,
as well as the traditional xhci fix rounding out the batch.
All have been in linux-next with no reported issues"
* tag 'usb-4.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
xhci: fix deadlock at host remove by running watchdog correctly
USB: serial: ch341: fix control-message error handling
usb: musb: fix runtime PM in debugfs
wusbcore: Fix one more crypto-on-the-stack bug
USB: serial: kl5kusb105: fix line-state error handling
USB: serial: ch341: fix baud rate and line-control handling
USB: serial: ch341: fix line settings after reset-resume
USB: serial: ch341: fix resume after reset
USB: serial: ch341: fix open error handling
USB: serial: ch341: fix modem-control and B0 handling
USB: serial: ch341: fix open and resume after B0
USB: serial: ch341: fix initial modem-control state
The sysrq input handler should be attached to the input device which has
a left alt key.
On 32-bit kernels, some input devices which has a left alt key cannot
attach sysrq handler. Because the keybit bitmap in struct input_device_id
for sysrq is not correctly initialized. KEY_LEFTALT is 56 which is
greater than BITS_PER_LONG on 32-bit kernels.
I found this problem when using a matrix keypad device which defines
a KEY_LEFTALT (56) but doesn't have a KEY_O (24 == 56%32).
Cc: Jiri Slaby <jslaby@suse.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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