When vfs_submount was added the test to limit automounts from
filesystems that with s_user_ns != &init_user_ns accidentially left
in follow_automount. The test was never about any security concerns
and was always about how do we implement this for filesystems whose
s_user_ns != &init_user_ns.
At the moment this check makes no difference as there are no
filesystems that both set FS_USERNS_MOUNT and implement d_automount.
Remove this check now while I am thinking about it so there will not
be odd booby traps for someone who does want to make this combination
work.
vfs_submount still needs improvements to allow this combination to work,
and vfs_submount contains a check that presents a warning.
The autofs4 filesystem could be modified to set FS_USERNS_MOUNT and it would
need not work on this code path, as userspace performs the mounts.
Fixes: 93faccbbfa95 ("fs: Better permission checking for submounts") Fixes: aeaa4a79ff6a ("fs: Call d_automount with the filesystems creds") Acked-by: Ian Kent <raven@themaw.net> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
on T81 there are only 4 cores, hence setting max queue count to 4
would leave nothing for XDP_TX. This patch fixes this by doubling
max queue count in above scenarios.
Signed-off-by: Sunil Goutham <sgoutham@cavium.com> Signed-off-by: cjacob <cjacob@caviumnetworks.com> Signed-off-by: Aleksey Makarov <aleksey.makarov@cavium.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some drivers (like nand_hynix.c) call ->cmdfunc() with NAND_CMD_NONE
and a column address and expect the controller to only send address
cycles. Right now, the default ->cmdfunc() implementations provided by
the core do not filter out the command cycle in this case and forwards
the request to the controller driver through the ->cmd_ctrl() method.
The thing is, NAND controller drivers can get this wrong and send a
command cycle with a NAND_CMD_NONE opcode and since NAND_CMD_NONE is
-1, and the command field is usually casted to an u8, we end up sending
the 0xFF command which is actually a RESET operation.
Add conditions in nand_command[_lp]() functions to sending the initial
command cycle when command == NAND_CMD_NONE.
Currently it is possible to add or update socket policies, but
not clear them. Therefore, once a socket policy has been applied,
the socket cannot be used for unencrypted traffic.
This patch allows (privileged) users to clear socket policies by
passing in a NULL pointer and zero length argument to the
{IP,IPV6}_{IPSEC,XFRM}_POLICY setsockopts. This results in both
the incoming and outgoing policies being cleared.
The simple approach taken in this patch cannot clear socket
policies in only one direction. If desired this could be added
in the future, for example by continuing to pass in a length of
zero (which currently is guaranteed to return EMSGSIZE) and
making the policy be a pointer to an integer that contains one
of the XFRM_POLICY_{IN,OUT} enum values.
An alternative would have been to interpret the length as a
signed integer and use XFRM_POLICY_IN (i.e., 0) to clear the
input policy and -XFRM_POLICY_OUT (i.e., -1) to clear the output
policy.
The file /sys/module/firmware_class/parameters/path can be used
to set a custom firmware path. The fw_filesystem.sh script creates
a temporary directory to add a test firmware file to be used during
testing, in order for this to work it uses the custom path syfs file
and it was supposed to reset back the file on execution exit. The
script failed to do this due to a typo, it was using OLD_PATH instead
of OLD_FWPATH, since its inception since v3.17.
Its not as easy to just keep the old setting, it turns out that
resetting an empty setting won't actually do what we want, we need
to check if it was empty and set an empty space.
Without this we end up having the temporary path always set after
we run these tests.
The object info is being leaked on an error return path, fix this
by setting ret to -ENOMEM and exiting via the request_cleanup path
that will free info.
Detected by CoverityScan, CID#1408439 ("Resource Leak")
Fixes: c694b233295b ("crypto: cavium - Add the Virtual Function driver for CPT") Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If crypto_get_default_rng returns an error, the
function ecc_gen_privkey should return an error.
Instead, it currently tries to use the default_rng
nevertheless, thus creating a kernel panic with a
NULL pointer dereference.
Returning the error directly, as was supposedly
intended when looking at the code, fixes this.
Signed-off-by: Pierre Ducroquet <pinaraf@pinaraf.info> Reviewed-by: PrasannaKumar Muralidharan <prasannatsmkumar@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This splat cannot be generated by expedited grace periods because they
always invoke resched_cpu() on the current CPU, which is good because
expedited grace periods require that resched_cpu() unconditionally
succeed. However, other parts of RCU can tolerate resched_cpu() acting
as a no-op, at least as long as it doesn't happen too often.
This commit therefore makes resched_cpu() invoke resched_curr() only if
the CPU is either online or is the current CPU.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The rcutorture test suite occasionally provokes a splat due to invoking
rt_mutex_lock() which needs to boost the priority of a task currently
sitting on a runqueue that belongs to an offline CPU:
But the target task's priority has already been adjusted, so the only
purpose of switched_to_rt() invoking resched_curr() is to wake up the
CPU running some task that needs to be preempted by the boosted task.
But the CPU is offline, which presumably means that the task must be
migrated to some other CPU, and that this other CPU will undertake any
needed preemption at the time of migration. Because the runqueue lock
is held when resched_curr() is invoked, we know that the boosted task
cannot go anywhere, so it is not necessary to invoke resched_curr()
in this particular case.
This commit therefore makes switched_to_rt() refrain from invoking
resched_curr() when the target CPU is offline.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This code looks up a USB device node from a given parent USB device but
never dropped its reference to the returned node.
As only the address of the node is used for a later matching, the
reference can be dropped immediately.
Note that this trigger implementation confuses the description of the
USB device connected to a port with the port itself (which does not have
a device-tree representation).
Fixes: 4f04c210d031 ("usb: core: read USB ports from DT in the usbport LED trigger driver") Cc: Rafał Miłecki <rafal@milecki.pl> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The expectation in the FUSB302 driver is that a TX_SUCCESS event
should occur after a message has been sent, but before a GCRCSENT
event is raised to indicate successful receipt of a message from
the partner. However in some circumstances it is possible to see
the hardware raise a GCRCSENT event before a TX_SUCCESS event
is raised. The upshot of this is that the GCRCSENT handling portion
of code ends up reporting the GoodCRC message to TCPM because the
TX_SUCCESS event hasn't yet arrived to trigger a consumption of it.
When TX_SUCCESS is then raised by the chip it ends up consuming the
actual message that was meant for TCPM, and this incorrect sequence
results in a hard reset from TCPM.
To avoid this problem, this commit updates the message reading
code to check whether a GoodCRC message was received or not. Based
on this check it will either report that the previous transmission
has completed or it will pass the msg data to TCPM for futher
processing. This way the incorrect ordering of the events no longer
matters.
According to the datasheet, in Meson-GXBB/GXL series,
The clock gate bit for SARADC is HHI_GCLK_MPEG2 bit[22],
while clock gate bit for SANA is HHI_GCLK_MPEG0 bit[10].
Test passed at gxl-s905x-p212 board.
The following published datasheets are wrong and should be updated
[1] GXBB v1.1.4
[2] GXL v0.3_20170314
cec-clock is a fixed clock generator that is not controlled by i2c5 and
thus should not be a child of the i2c5 bus node. Rather, it should be
a child of the root node of the DT.
When we are in a search cycle, we try different combinations
of parameters. Those combinations are called 'columns'.
When we switch to a new column, we first need to check if
this column has a suitable rate, if not, we can't try it.
This means we must not erase the statistics we gathered
for the previous column until we are sure that we are
indeed switching column.
The code that tries to switch to a new column first sets
a whole bunch of things for the new column, and only then
checks that we can find suitable rates in that column.
While doing that, the code mistakenly erased the rate
statistics. This code was right until
struct iwl_scale_tbl_info grew up for TPC.
Fix this to make sure we don't erase the rate statistics
until we are sure that we can indeed switch to the new
column.
Note that this bug is really harmless since it causes a
change in the behavior only when we can't find any rate
in the new column which should really not happen. In the
case we do find a suitable we reset the rate statistics
a few lines later anyway.
ELO devices have one Button usage in GenDesk field, which makes hid-input map
it to BTN_LEFT; that confuses userspace, which then considers the device to be
a mouse/touchpad instead of touchscreen.
Fix that by unmapping BTN_LEFT and keeping only BTN_TOUCH in place.
Devices in "single finger hybrid mode" will send one report per finger,
on some devices only the first report of such a multi-packet frame will
contain a value for BTN_LEFT, in subsequent reports (if multiple fingers
are down) the value is always 0, causing hid-mt to report BTN_LEFT going
1 - 0 - 1 - 0 when pressing a clickpad and putting down a second finger.
This happens for example on USB 0603:0002 mt touchpads.
This commit fixes this by only reporting non touch fields for the first
packet of a (possibly) multi-packet frame.
Signed-off-by: Hans de Goede <hdegoede@redhat.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
HDMI 2.0 Appendix F suggest that we should keep sending the infoframe
when switching from 3D to 2D mode, even if the infoframe isn't strictly
necessary (ie. not needed to transmit the VIC or stereo information).
This is a workaround against some sinks that fail to realize that they
should switch from 3D to 2D mode when the source stop transmitting
the infoframe.
v2: Handle unpack() as well
Pull the length calculation into a helper
"Currently with fence-array, we have a potential deadlock situation. If
we fence_add_callback() on an array-fence, the array-fence's lock is
acquired first, and in it's ->enable_signaling() callback, it will install
cbs on it's array-member fences, so the array-member's lock is acquired
second.
But in the signal path, the array-member's lock is acquired first, and
the array-fence's lock acquired second."
Rob proposed either extensive changes to dma-fence to unnest the
fence-array signaling, or to defer the signaling onto a workqueue. This
is a more refined version of the later, that should keep the latency
of the fence signaling to a minimum by using an irq-work, which is
executed asap.
Reported-by: Rob Clark <robdclark@gmail.com> Suggested-by: Rob Clark <robdclark@gmail.com>
References: 1476635975-21981-1-git-send-email-robdclark@gmail.com Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Rob Clark <robdclark@gmail.com> Cc: Gustavo Padovan <gustavo.padovan@collabora.co.uk> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Christian König <christian.koenig@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org> Link: https://patchwork.freedesktop.org/patch/msgid/20171114162719.30958-1-chris@chris-wilson.co.uk Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since drm_edid_to_eld() knows the connector type, we can set the type in
ELD while at it. Most connectors this gets called on are not DP
encoders, and with the HDMI type being 0, this does not change behaviour
for non-DP.
For i915 having this in place earlier would have saved a considerable
amount of debugging that lead to the fix 2d8f63297b9f ("drm/i915: always
update ELD connector type after get modes"). I don't see other drivers,
even the ones calling drm_edid_to_eld() on DP connectors, setting the
connector type in ELD.
Cc: Alex Deucher <alexander.deucher@amd.com> Cc: Christian König <christian.koenig@amd.com> Cc: Archit Taneja <architt@codeaurora.org> Cc: Andrzej Hajda <a.hajda@samsung.com> Cc: Russell King <linux@armlinux.org.uk> Cc: CK Hu <ck.hu@mediatek.com> Cc: Philipp Zabel <p.zabel@pengutronix.de> Cc: Ben Skeggs <bskeggs@redhat.com> Cc: Mark Yao <mark.yao@rock-chips.com> Cc: Benjamin Gaignard <benjamin.gaignard@linaro.org> Cc: Vincent Abriou <vincent.abriou@st.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Eric Anholt <eric@anholt.net> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Acked-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/d527b31619528c477c2c136f25cdf118bc0cfc1d.1509545641.git.jani.nikula@intel.com Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reported-by: Christoph Biedl <linux-kernel.bfrz@manchmal.in-ulm.de> Cc: Anand Jain <anand.jain@oracle.com> Cc: Liu Bo <bo.li.liu@oracle.com> Cc: David Sterba <dsterba@suse.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
After v4.12 commit e2460f2a4bc7 ("dm: mark targets that pass integrity
data"), dm-multipath, e.g. on DIF+DIX SCSI disk paths, does not support
block integrity any more. So add it to the whitelist.
This is also a pre-requisite to use block integrity with other dm layer(s)
on top of multipath, such as kpartx partitions (dm-linear) or LVM.
Also, bump target version to reflect this fix.
Fixes: e2460f2a4bc7 ("dm: mark targets that pass integrity data") Cc: <stable@vger.kernel.org> #4.12+ Bisected-by: Fedor Loshakov <loshakov@linux.vnet.ibm.com> Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It will get the wrong virtual address because port->mapbase is not added
the correct reg-offset yet. We have to update it before earlycon_map()
is called
Signed-off-by: Greentime Hu <greentime@andestech.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: stable@vger.kernel.org Fixes: 088da2a17619 ("of: earlycon: Initialize port fields from DT properties") Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is a followup on 44117a1d1732 ("serial: core: mark port as
initialized after successful IRQ change").
Nikola has been using autoconfig via setserial and reported a crash
similar to what I fixed in the earlier mentioned commit. Here I do the
same fixup for the autoconfig. I wasn't sure that this is the right
approach. Nikola confirmed that it fixes his crash.
Fixes: b3b576461864 ("tty: serial_core: convert uart_open to use tty_port_open") Link: http://lkml.kernel.org/r/20180131072000.GD1853@localhost.localdomain Reported-by: Nikola Ciprich <nikola.ciprich@linuxbox.cz> Tested-by: Nikola Ciprich <nikola.ciprich@linuxbox.cz> Cc: <stable@vger.kernel.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Tested-by: Nikola Ciprich <nikola.ciprich@linuxbox.cz> Acked-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To reproduce the lock up do the following
- connect otg host adapter and a USB device to the dual-role port
so that it is in host mode.
- suspend to mem.
- disconnect otg adapter.
- resume the system.
If we call dwc3_host_exit() before tasks are thawed
xhci_plat_remove() seems to lock up at the second usb_remove_hcd() call.
To work around this we queue the _dwc3_set_mode() work on
the system_freezable_wq.
Fixes: 41ce1456e1db ("usb: dwc3: core: make dwc3_set_mode() work properly") Cc: <stable@vger.kernel.org> # v4.12+ Suggested-by: Manu Gautam <mgautam@codeaurora.org> Signed-off-by: Roger Quadros <rogerq@ti.com> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When I debug a kernel crash issue in funcitonfs, found ffs_data.ref
overflowed, While functionfs is unmounting, ffs_data is put twice.
Commit 43938613c6fd ("drivers, usb: convert ffs_data.ref from atomic_t to
refcount_t") can avoid refcount overflow, but that is risk some situations.
So no need put ffs data in ffs_fs_kill_sb, already put in ffs_data_closed.
The issue can be reproduced in Mediatek mt6763 SoC, ffs for ADB device.
KASAN enabled configuration reports use-after-free errro.
BUG: KASAN: use-after-free in refcount_dec_and_test+0x14/0xe0 at addr ffffffc0579386a0
Read of size 4 by task umount/4650
====================================================
BUG kmalloc-512 (Tainted: P W O ): kasan: bad access detected
-----------------------------------------------------------------------------
Currently the driver attempts to spin lock on udc->lock before a NULL
pointer check is performed on udc, hence there is a potential null
pointer dereference on udc->lock. Fix this by moving the null check
on udc before the lock occurs.
Fixes: ea6873a45a22 ("usbip: vudc: Add SysFS infrastructure for VUDC") Signed-off-by: Colin Ian King <colin.king@canonical.com> Acked-by: Shuah Khan <shuahkh@osg.samsung.com> Reviewed-by: Krzysztof Opasiak <k.opasiak@samsung.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is a lock ordering created between mmap_sem and inode->i_rwsem
causing a lockdep splat [2] during a syzcaller test, this patch fixes
the issue by unlocking the mutex earlier. Functionally that's Ok since
we don't need to protect vfs_llseek.
Fixes: cbeef22fd611 ("usb: uas: unconditionally bring back host after reset") Signed-off-by: Oliver Neukum <oneukum@suse.com> CC: stable@kernel.org Acked-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On our at91sam9260 based board the usart0 and usart1 ports report
their versions (ATMEL_US_VERSION) as 0x10302. This version is not
included in the current checks in the driver.
Signed-off-by: Jonas Danielsson <jonas@orbital-systems.com> Acked-by: Richard Genoud <richard.genoud@gmail.com> Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This can be prevented by doing a dummy read of the RX data register.
This issue affects both HSCIF and SCIF ports. Reported for R-Car H3 ES2.0;
reproduced and fixed on H3 ES1.1. Probably affects other R-Car platforms
as well.
When a USB device gets plugged on ASUS PRIME B350M-A's front ports, the
xHC stops working:
[ 549.114587] xhci_hcd 0000:02:00.0: WARN: xHC CMD_RUN timeout
[ 549.114608] suspend_common(): xhci_pci_suspend+0x0/0xc0 returns -110
[ 549.114638] xhci_hcd 0000:02:00.0: can't suspend (hcd_pci_runtime_suspend returned -110)
Delay before running xHC command CMD_RUN can workaround the issue.
Use a new quirk to make the delay only targets to the affected xHC.
The ALC5651 does not like multi-write accesses, avoid them. This fixes:
rt5651 i2c-10EC5651:00: Unable to sync registers 0x27-0x28. -121
Errors on resume (and all registers after the registers in the error not
being synced).
Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Mark Brown <broonie@kernel.org> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Normal 512-byte get/set of a TLV isn't supported but we were
registering the normal get/set anyway and relying on omitting
the SNDRV_CTL_ELEM_ACCESS_[READ|WRITE] flags to prevent them
being called.
Trouble is if this gets broken in the core ALSA code - as it has
been since at least 4.14 - the standard get/set can be called
unexpectedly and corrupt memory.
There's no point providing functions that won't be called and
it's a trivial change. The benefit is that if the ALSA core gets
broken again we get a big fat immediate NULL dereference instead
of a memory corruption timebomb.
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com> Signed-off-by: Mark Brown <broonie@kernel.org> Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 8419caa72702 ("ASoC: sgtl5000: Do not disable regulators in
SND_SOC_BIAS_OFF") causes the sgtl5000 to fail after a suspend/resume
sequence:
Playing WAVE '/media/a2002011001-e02.wav' : Signed 16 bit Little
Endian, Rate 44100 Hz, Stereo
aplay: pcm_write:2051: write error: Input/output error
The problem is caused by the fact that the aforementioned commit
dropped the cache handling, so re-introduce the register map
resync to fix the problem.
Suggested-by: Mark Brown <broonie@kernel.org> Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com> Signed-off-by: Mark Brown <broonie@kernel.org> Cc: <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On i386, there are 2 types of PLTs, PIC and non-PIC. PIE and shared
objects must use PIC PLT. To use PIC PLT, you need to load
_GLOBAL_OFFSET_TABLE_ into EBX first. There is no need for that on
x86-64 since x86-64 uses PC-relative PLT.
On x86-64, for 32-bit PC-relative branches, we can generate PLT32
relocation, instead of PC32 relocation, which can also be used as
a marker for 32-bit PC-relative branches. Linker can always reduce
PLT32 relocation to PC32 if function is defined locally. Local
functions should use PC32 relocation. As far as Linux kernel is
concerned, R_X86_64_PLT32 can be treated the same as R_X86_64_PC32
since Linux kernel doesn't use PLT.
R_X86_64_PLT32 for 32-bit PC-relative branches has been enabled in
binutils master branch which will become binutils 2.31.
[ hjl is working on having better documentation on this all, but a few
more notes from him:
"PLT32 relocation is used as marker for PC-relative branches. Because
of EBX, it looks odd to generate PLT32 relocation on i386 when EBX
doesn't have GOT.
As for symbol resolution, PLT32 and PC32 relocations are almost
interchangeable. But when linker sees PLT32 relocation against a
protected symbol, it can resolved locally at link-time since it is
used on a branch instruction. Linker can't do that for PC32
relocation"
but for the kernel use, the two are basically the same, and this
commit gets things building and working with the current binutils
master - Linus ]
commit f5e64032a799 ("net: phy: fix resume handling") changes the
locking semantics for phy_resume() such that the caller now needs to
hold the phy mutex. Not all call sites were adopted to this new
semantic, resulting in warnings from the added
WARN_ON(!mutex_is_locked(&phydev->lock)). Rather than change the
semantics, add a __phy_resume() and restore the old behavior of
phy_resume().
Reported-by: Heiner Kallweit <hkallweit1@gmail.com> Fixes: f5e64032a799 ("net: phy: fix resume handling") Signed-off-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When a PHY has the BMCR_PDOWN bit set, it may decide to ignore writes
to other registers, or reset the registers to power-on defaults.
Micrel PHYs do this for their interrupt registers.
The current structure of phylib tries to enable interrupts before
resuming (and releasing) the BMCR_PDOWN bit. This fails, causing
Micrel PHYs to stop working after a suspend/resume sequence if they
are using interrupts.
Fix this by ensuring that the PHY driver resume methods do not take
the phydev->lock mutex themselves, but the callers of phy_resume()
take that lock. This then allows us to move the call to phy_resume()
before we enable interrupts in phy_start().
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Disable the kprobe probing of the entry trampoline:
.entry_trampoline is a code area that is used to ensure page table
isolation between userspace and kernelspace.
At the beginning of the execution of the trampoline, we load the
kernel's CR3 register. This has the effect of enabling the translation
of the kernel virtual addresses to physical addresses. Before this
happens most kernel addresses can not be translated because the running
process' CR3 is still used.
If a kprobe is placed on the trampoline code before that change of the
CR3 register happens the kernel crashes because int3 handling pages are
not accessible.
To fix this, add the .entry_trampoline section to the kprobe blacklist
to prohibit the probing of code before all the kernel pages are
accessible.
Signed-off-by: Francis Deslauriers <francis.deslauriers@efficios.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: mathieu.desnoyers@efficios.com Cc: mhiramat@kernel.org Link: http://lkml.kernel.org/r/1520565492-4637-2-git-send-email-francis.deslauriers@efficios.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix the objtool build when cross-compiling a 64-bit kernel on a 32-bit
host. This also simplifies read_retpoline_hints() a bit and makes its
implementation similar to most of the other annotation reading
functions.
Reported-by: Sven Joachim <svenjoac@gmx.de> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: b5bc2231b8ad ("objtool: Add retpoline validation") Link: http://lkml.kernel.org/r/2ca46c636c23aa9c9d57d53c75de4ee3ddf7a7df.1520380691.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Continue the switch table detection whack-a-mole. Add a check to
distinguish KASAN data reads from switch data reads. The switch jump
tables in .rodata have relocations associated with them.
This fixes the following warning:
crypto/asymmetric_keys/x509_cert_parser.o: warning: objtool: x509_note_pkey_algo()+0xa4: sibling call from callable instruction with modified stack frame
Disable retpoline validation in objtool if your compiler sucks, and otherwise
select the validation stuff for CONFIG_RETPOLINE=y (most builds would already
have it set due to ORC).
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Geert reported commit ae6b289a3789 ("kbuild: Set KBUILD_CFLAGS before
incl. arch Makefile") broke cross-compilation using a cross-compiler
that supports less compiler options than the host compiler.
For example,
cc1: error: unrecognized command line option "-Wno-unused-but-set-variable"
This problem happens on architectures that setup CROSS_COMPILE in their
arch/*/Makefile.
Move the cc-option and cc-disable-warning back to the original position,
but keep the Clang target options untouched.
The top Makefile is divided into some sections such as mixed targets,
config targets, build targets, etc.
When we build mixed targets, Kbuild just invokes submake to process
them one by one. In this case, compiler-related variables like CC,
KBUILD_CFLAGS, etc. are unneeded.
Check what kind of targets we are building first, and parse variables
for building only when necessary.
Paravirt emits indirect calls which get flagged by objtool retpoline
checks, annotate it away because all these indirect calls will be
patched out before we start userspace.
This patching happens through alternative_instructions() ->
apply_paravirt() -> pv_init_ops.patch() which will eventually end up
in paravirt_patch_default(). This function _will_ write direct
alternatives.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
firmware_restrict_branch_speculation_*() recently started using
preempt_enable()/disable(), but those are relatively high level
primitives and cause build failures on some 32-bit builds.
Since we want to keep <asm/nospec-branch.h> low level, convert
them to macros to avoid header hell...
This reverts commit 1dde7415e99933bb7293d6b2843752cbdb43ec11. By putting
the RSB filling out of line and calling it, we waste one RSB slot for
returning from the function itself, which means one fewer actual function
call we can make if we're doing the Skylake abomination of call-depth
counting.
It also changed the number of RSB stuffings we do on vmexit from 32,
which was correct, to 16. Let's just stop with the bikeshedding; it
didn't actually *fix* anything anyway.
Omitting suffixes from instructions in AT&T mode is bad practice when
operand size cannot be determined by the assembler from register
operands, and is likely going to be warned about by upstream GAS in the
future (mine does already). Add the single missing suffix here.
Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/5A8AF5F602000078001A9230@prv-mh.provo.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
df3405245a ("x86/asm: Add suffix macro for GEN_*_RMWcc()")
... introduced "suffix" RMWcc operations, adding bogus clobber specifiers:
For one, on x86 there's no point explicitly clobbering "cc".
In fact, with GCC properly fixed, this results in an overlap being detected by
the compiler between outputs and clobbers.
Furthermore it seems bad practice to me to have clobber specification
and use of the clobbered register(s) disconnected - it should rather be
at the invocation place of that GEN_{UN,BIN}ARY_SUFFIXED_RMWcc() macros
that the clobber is specified which this particular invocation needs.
Drop the "cc" clobber altogether and move the "cx" one to refcount.h.
Signed-off-by: Jan Beulich <jbeulich@suse.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/5A8AF1F802000078001A91E1@prv-mh.provo.novell.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On some x86 CPU microarchitectures using 'xorq' to clear general-purpose
registers is slower than 'xorl'. As 'xorl' is sufficient to clear all
64 bits of these registers due to zero-extension [*], switch the x86
64-bit entry code to use 'xorl'.
No change in functionality and no change in code size.
[*] According to Intel 64 and IA-32 Architecture Software Developer's
Manual, section 3.4.1.1, the result of 32-bit operands are "zero-
extended to a 64-bit result in the destination general-purpose
register." The AMD64 Architecture Programmer’s Manual Volume 3,
Appendix B.1, describes the same behaviour.
Suggested-by: Denys Vlasenko <dvlasenk@redhat.com> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20180214175924.23065-3-linux@dominikbrodowski.net
[ Improved on the changelog a bit. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Play a little trick in the generic PUSH_AND_CLEAR_REGS macro
to insert the GP registers "above" the original return address.
This allows us to (re-)insert the macro in error_entry() and
paranoid_entry() and to remove it from the idtentry macro. This
reduces the static footprint significantly:
text data bss dec hex filename
24307 0 0 24307 5ef3 entry_64.o-orig
20987 0 0 20987 51fb entry_64.o
Co-developed-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20180214175924.23065-2-linux@dominikbrodowski.net
[ Small tweaks to comments. ] Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The nospec.h header expects the per-architecture header file
<asm/barrier.h> to optionally define array_index_mask_nospec(). Include
that dependency to prevent inadvertent fallback to the default
array_index_mask_nospec() implementation.
The default implementation may not provide a full mitigation
on architectures that perform data value speculation.
Reported-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arch@vger.kernel.org Link: http://lkml.kernel.org/r/151881605404.17395.1341935530792574707.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are multiple problems with the dynamic sanity checking in
array_index_nospec_mask_check():
* It causes unnecessary overhead in the 32-bit case since integer sized
@index values will no longer cause the check to be compiled away like
in the 64-bit case.
* In the 32-bit case it may trigger with user controllable input when
the expectation is that should only trigger during development of new
kernel enabling.
* The macro reuses the input parameter in multiple locations which is
broken if someone passes an expression like 'index++' to
array_index_nospec().
Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arch@vger.kernel.org Link: http://lkml.kernel.org/r/151881604278.17395.6605847763178076520.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reading mips_cpc_base value from the DT allows each platform to
define it according to its needs. This is especially convenient
for MIPS_GENERIC kernel where this kind of information should be
determined in runtime.
Use mti,mips-cpc compatible string with just a reg property to
specify the register location for your platform.
Signed-off-by: Paul Burton <paul.burton@mips.com> Signed-off-by: Miodrag Dinic <miodrag.dinic@mips.com> Signed-off-by: Aleksandar Markovic <aleksandar.markovic@mips.com> Cc: linux-mips@linux-mips.org Cc: Ralf Baechle <ralf@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/18513/ Signed-off-by: James Hogan <jhogan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
During error test case where switch port status is toggled from enable to
disable, following stack trace is seen which indicates recursion trying to
send terminate exchange. This regression was introduced by commit 82de802ad46e ("scsi: qla2xxx: Preparation for Target MQ.")
BUG: stack guard page was hit at ffffb96488383ff8 (stack is ffffb96488384000..ffffb96488387fff)
BUG: stack guard page was hit at ffffb964886c3ff8 (stack is ffffb964886c4000..ffffb964886c7fff)
kernel stack overflow (double-fault): 0000 [#1] SMP
qlt_term_ctio_exchange+0x9c/0xb0 [qla2xxx]
qlt_term_ctio_exchange+0x9c/0xb0 [qla2xxx]
qlt_term_ctio_exchange+0x9c/0xb0 [qla2xxx]
qlt_term_ctio_exchange+0x9c/0xb0 [qla2xxx]
qlt_term_ctio_exchange+0x9c/0xb0 [qla2xxx]
Fixes: 82de802ad46e ("scsi: qla2xxx: Preparation for Target MQ.") Cc: <stable@vger.kernel.org> #4.10 Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch fixes regression added by commit d74595278f4ab
("scsi: qla2xxx: Add multiple queue pair functionality.").
When driver is not able to get reqeusted IRQs from the system, driver will
attempt tp clean up memory before failing hardware probe. During this cleanup,
driver assigns NULL value to the pointer which has not been allocated by
driver yet. This results in a NULL pointer access.
Log file will show following message and stack trace
qla2xxx [0000:a3:00.1]-00c7:21: MSI-X: Failed to enable support, giving up -- 32/-1.
qla2xxx [0000:a3:00.1]-0037:21: Falling back-to MSI mode --1.
qla2xxx [0000:a3:00.1]-003a:21: Failed to reserve interrupt 821 already in use.
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: [<ffffffffc010c4b6>] qla2x00_probe_one+0x18b6/0x2730 [qla2xxx]
PGD 0
Oops: 0002 [#1] SMP
With the alc289, the Pin 0x1b is Headphone-Mic, so we should assign
ALC269_FIXUP_DELL4_MIC_NO_PRESENCE rather than
ALC225_FIXUP_DELL1_MIC_NO_PRESENCE to it. And this change is suggested
by Kailang of Realtek and is verified on the machine.
Fixes: 3f2f7c553d07 ("ALSA: hda - Fix headset mic detection problem for two Dell machines") Cc: Kailang Yang <kailang@realtek.com> Cc: <stable@vger.kernel.org> Signed-off-by: Hui Wang <hui.wang@canonical.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch is an attempt for further hardening against races between
the concurrent write and ioctls. The previous fix d15d662e89fc
("ALSA: seq: Fix racy pool initializations") covered the race of the
pool initialization at writer and the pool resize ioctl by the
client->ioctl_mutex (CVE-2018-1000004). However, basically this mutex
should be applied more widely to the whole write operation for
avoiding the unexpected pool operations by another thread.
The only change outside snd_seq_write() is the additional mutex
argument to helper functions, so that we can unlock / relock the given
mutex temporarily during schedule() call for blocking write.
This is a fix for a (sort of) fallout in the recent commit d15d662e89fc ("ALSA: seq: Fix racy pool initializations") for
CVE-2018-1000004.
As the pool resize deletes the existing cells, it may lead to a race
when another thread is writing concurrently, eventually resulting a
UAF.
A simple workaround is not to allow the pool resizing when the pool is
in use. It's an invalid behavior in anyway.
One version of Lenovo Thinkpad T570 did not use ALC298
(like other Kaby Lake devices). Instead it uses ALC292.
In order to make the Lenovo dock working with that codec
the dock quirk for ALC292 will be used.
The dock line-out pin (NID 0x17 of ALC3254 codec) on Dell Precision
7520 may route to three different DACs, 0x02, 0x03 and 0x06. The
first two DACS have the volume amp controls while the last one
doesn't. And unfortunately, the auto-parser assigns this pin to DAC3,
resulting in the non-working volume control for the line out.
Fix it by disabling the routing to DAC3 on the corresponding pin.
This platform was only one phone Jack.
Add dummy lineout verb to fix automute mode disable.
This just the workaround.
[ More background information:
since the platform has only a headphone jack without speaker, the
driver doesn't create the auto-mute control. Meanwhile we do update
the headset mode via the automute hook in the driver, thus with this
setup, the headset won't be updated any longer.
By adding a dummy line-out pin here, the auto-mute is added by the
driver, and the headset update is triggered properly.
Note that this is different from the other
ALC274_FIXUP_DELL_AIO_LINEOUT_VERB, which has the real line-out pin,
while this quirk adds a dummy line-out pin. -- tiwai ]
1) It's known that hypervisors lie about the environment anyhow (host
mismatch)
2) Even if the hypervisor (Xen, KVM, VMWare, etc) provided a valid
"correct" value, it all gets to be very murky when migration happens
(do you provide the "new" microcode of the machine?).
And in reality the cloud vendors are the ones that should make sure that
the microcode that is running is correct and we should just sing lalalala
and trust them.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Wanpeng Li <kernellwp@gmail.com> Cc: kvm <kvm@vger.kernel.org> Cc: Krčmář <rkrcmar@redhat.com> Cc: Borislav Petkov <bp@alien8.de> CC: "H. Peter Anvin" <hpa@zytor.com> CC: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20180226213019.GE9497@char.us.oracle.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
trigger_on() means that the trigger is available but not ready, however
trigger_on() was making it ready. That can segfault if the signal comes
before trigger_ready(). e.g. (USR2 signal delivery not shown)
directory is a global timer value for MCE polling. If it is changed by one
CPU, mce_restart() broadcasts the event to other CPUs to delete and restart
the MCE polling timer and __mcheck_cpu_init_timer() reinitializes the
mce_timer variable.
If more than one CPU writes a specific value to the check_interval file
concurrently, mce_timer is not protected from such concurrent accesses and
all kinds of explosions happen. Since only root can write to those sysfs
variables, the issue is not a big deal security-wise.
However, concurrent writes to these configuration variables is void of
reason so the proper thing to do is to serialize the access with a mutex.
Boris:
- Make store_int_with_restart() use device_store_ulong() to filter out
negative intervals
- Limit min interval to 1 second
- Correct locking
- Massage commit message
Updating microcode used to be relatively rare. Now that it has become
more common we should save the microcode version in a machine check
record to make sure that those people looking at the error have this
important information bundled with the rest of the logged information.
This is an incomplete fix: it does not catch duplicate UUIDs earlier
when things are still unattached. It does not unregister the device.
Further changes to cope better with this are planned but conflict with
Coly's ongoing improvements to handling device errors. In the meantime,
one can manually stop the device after this has happened.
When registering duplicate cache device in register_cache(), after failure
on calling register_cache_set(), bch_cache_release() will be called, then
bdev will be freed, so bdevname(bdev, name) caused kernel crash.
Since bch_cache_release() will free bdev, so in this patch we make sure
bdev being freed if register_cache() fail, and do not free bdev again in
register_bcache() when register_cache() fail.
Signed-off-by: Tang Junhui <tang.junhui@zte.com.cn> Reported-by: Marc MERLIN <marc@merlins.org> Tested-by: Michael Lyle <mlyle@lyle.org> Reviewed-by: Michael Lyle <mlyle@lyle.org> Cc: <stable@vger.kernel.org> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>