We like living dangerously. Nothing explicitely forbids stack-protector
to be used in the HYP code, while distributions routinely compile their
kernel with it. We're just lucky that no code actually triggers the
instrumentation.
Let's not try our luck for much longer, and disable stack-protector
for code living at HYP.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We like living dangerously. Nothing explicitely forbids stack-protector
to be used in the EL2 code, while distributions routinely compile their
kernel with it. We're just lucky that no code actually triggers the
instrumentation.
Let's not try our luck for much longer, and disable stack-protector
for code living at EL2.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In commit dc3106690b20 ("powerpc: tm: Always use fp_state and vr_state
to store live registers"), a section of code was removed that copied
the current state to checkpointed state. That code should not have been
removed.
When an FP (Floating Point) unavailable is taken inside a transaction,
we need to abort the transaction. This is because at the time of the
tbegin, the FP state is bogus so the state stored in the checkpointed
registers is incorrect. To fix this, we treclaim (to get the
checkpointed GPRs) and then copy the thread_struct FP live state into
the checkpointed state. We then trecheckpoint so that the FP state is
correctly restored into the CPU.
The copying of the FP registers from live to checkpointed is what was
missing.
This simplifies the logic slightly from the original patch.
tm_reclaim_thread() will now always write the checkpointed FP
state. Either the checkpointed FP state will be written as part of
the actual treclaim (in tm.S), or it'll be a copy of the live
state. Which one we use is based on MSR[FP] from userspace.
Similarly for VMX.
Fixes: dc3106690b20 ("powerpc: tm: Always use fp_state and vr_state to store live registers") Signed-off-by: Michael Neuling <mikey@neuling.org> Reviewed-by: cyrilbur@gmail.com Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The page table dump code doesn't know about huge pages, so currently
it crashes (or walks random memory, usually leading to a crash), if it
finds a huge page. On Book3S we only see huge pages in the Linux page
tables when we're using the P9 Radix MMU.
Teaching the code to properly handle huge pages is a bit more involved,
so for now just prevent the crash.
Fixes: 8eb07b187000 ("powerpc/mm: Dump linux pagetables") Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Debug interrupts can be taken during interrupt entry, since interrupt
entry does not automatically turn them off. The kernel will check
whether the faulting instruction is between [interrupt_base_book3e,
__end_interrupts], and if so clear MSR[DE] and return.
However, when the kernel is built with CONFIG_RELOCATABLE, it can't use
LOAD_REG_IMMEDIATE(r14,interrupt_base_book3e) and
LOAD_REG_IMMEDIATE(r15,__end_interrupts), as they ignore relocation.
Thus, if the kernel is actually running at a different address than it
was built at, the address comparison will fail, and the exception entry
code will hang at kernel_dbg_exc.
r2(toc) is also not usable here, as r2 still holds data from the
interrupted context, so LOAD_REG_ADDR() doesn't work either. So we use
the *name@got* to get the EV of two labels directly.
Test programs test.c shows as follows:
int main(int argc, char *argv[])
{
if (access("/proc/sys/kernel/perf_event_paranoid", F_OK) == -1)
printf("Kernel doesn't have perf_event support\n");
}
Steps to reproduce the bug, for example:
1) ./gdb ./test
2) (gdb) b access
3) (gdb) r
4) (gdb) s
Signed-off-by: Liu Hailong <liu.hailong6@zte.com.cn> Signed-off-by: Jiang Xuexin <jiang.xuexin@zte.com.cn> Reviewed-by: Jiang Biao <jiang.biao2@zte.com.cn> Reviewed-by: Liu Song <liu.song11@zte.com.cn> Reviewed-by: Huang Jian <huang.jian@zte.com.cn>
[scottwood: cleaned up commit message, and specified bad behavior
as a hang rather than an oops to correspond to mainline kernel behavior] Fixes: 1cb6e0649248 ("powerpc/book3e: support CONFIG_RELOCATABLE") Signed-off-by: Scott Wood <oss@buserror.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 616badd2fb49 ("powerpc/powernv: Use OPAL call for TCE kill on
NVLink2") forced all TCE kills to go via the OPAL call for
NVLink2. However the PHB3 implementation of TCE kill was still being
called directly from some functions which in some circumstances caused
a machine check.
This patch adds an equivalent IODA2 version of the function which uses
the correct invalidation method depending on PHB model and changes all
external callers to use it instead.
Fixes: 616badd2fb49 ("powerpc/powernv: Use OPAL call for TCE kill on NVLink2") Signed-off-by: Alistair Popple <alistair@popple.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The CMA pages migration code does not support compound pages at
the moment so it performs few tests before proceeding to actual page
migration.
One of the tests - PageTransHuge() - has VM_BUG_ON_PAGE(PageTail()) as
it is designed to be called on head pages only. Since we also test for
PageCompound(), and it contains PageTail() and PageHead(), we can
simplify the check by leaving just PageCompound() and therefore avoid
possible VM_BUG_ON_PAGE.
Fixes: 2e5bbb5461f1 ("KVM: PPC: Book3S HV: Migrate pinned pages out of CMA") Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Acked-by: Balbir Singh <bsingharora@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For CPUs present at boot each logical CPU acquires a reference to the
associated device node of the core. This happens in register_cpu() which
is called by topology_init(). The result of this is that we end up with
a reference held by each thread of the core. However, these references
are never freed if the CPU core is DLPAR removed.
This patch fixes the reference leaks by acquiring and releasing the references
in the CPU hotplug callbacks un/register_cpu_online(). With this patch symmetric
reference counting is observed with both CPUs present at boot, and those DLPAR
added after boot.
Historically struct device_node references were tracked using a kref embedded as
a struct field. Commit 75b57ecf9d1d ("of: Make device nodes kobjects so they
show up in sysfs") (Mar 2014) refactored device_nodes to be kobjects such that
the device tree could by more simply exposed to userspace using sysfs.
Commit 0829f6d1f69e ("of: device_node kobject lifecycle fixes") (Mar 2014)
followed up these changes to better control the kobject lifecycle and in
particular the referecne counting via of_node_get(), of_node_put(), and
of_node_init().
A result of this second commit was that it introduced an of_node_put() call when
a dynamic node is detached, in of_node_remove(), that removes the initial kobj
reference created by of_node_init().
Traditionally as the original dynamic device node user the pseries code had
assumed responsibilty for releasing this final reference in its platform
specific DLPAR detach code.
This patch fixes a refcount underflow introduced by commit 0829f6d1f6, and
recently exposed by the upstreaming of the recount API.
Messages like the following are no longer seen in the kernel log with this
patch following DLPAR remove operations of cpus and pci devices.
rpadlpar_io: slot PHB 72 removed
refcount_t: underflow; use-after-free.
------------[ cut here ]------------
WARNING: CPU: 5 PID: 3335 at lib/refcount.c:128 refcount_sub_and_test+0xf4/0x110
Fixes: 0829f6d1f69e ("of: device_node kobject lifecycle fixes") Signed-off-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
[mpe: Make change log commit references more verbose] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
machine_check_early() gets called in real mode. The very first time when
add_taint() is called, it prints a warning which ends up calling opal
call (that uses OPAL_CALL wrapper) for writing it to console. If we get a
very first machine check while we are in opal we are doomed. OPAL_CALL
overwrites the PACASAVEDMSR in r13 and in this case when we are done with
MCE handling the original opal call will use this new MSR on it's way
back to opal_return. This usually leads to unexpected behaviour or the
kernel to panic. Instead move the add_taint() call later in the virtual
mode where it is safe to call.
This is broken with current FW level. We got lucky so far for not getting
very first MCE hit while in OPAL. But easily reproducible on Mambo.
Fixes: 27ea2c420cad ("powerpc: Set the correct kernel taint on machine check errors.") Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
eeh_handle_special_event() is called when an EEH event is detected but
can't be narrowed down to a specific PE. This function looks through
every PE to find one in an erroneous state, then calls the regular event
handler eeh_handle_normal_event() once it knows which PE has an error.
However, if eeh_handle_normal_event() found that the PE cannot possibly
be recovered, it will free it, rendering the passed PE stale.
This leads to a use after free in eeh_handle_special_event() as it attempts to
clear the "recovering" state on the PE after eeh_handle_normal_event() returns.
Thus, make sure the PE is valid when attempting to clear state in
eeh_handle_special_event().
Fixes: 8a6b1bc70dbb ("powerpc/eeh: EEH core to handle special event") Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Russell Currey <ruscur@russell.cc> Reviewed-by: Gavin Shan <gwshan@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
powerpc expects IRQs to already be (soft) disabled when switch_mm() is
called, as made clear in the commit message of 9c1e105238c4 ("powerpc: Allow
perf_counters to access user memory at interrupt time").
Aside from any race conditions that might exist between switch_mm() and an IRQ,
there is also an unconditional hard_irq_disable() in switch_slb(). If that isn't
followed at some point by an IRQ enable then interrupts will remain disabled
until we return to userspace.
It is true that when switch_mm() is called from the scheduler IRQs are off, but
not when it's called by use_mm(). Looking closer we see that last year in commit f98db6013c55 ("sched/core: Add switch_mm_irqs_off() and use it in the scheduler")
this was made more explicit by the addition of switch_mm_irqs_off() which is now
called by the scheduler, vs switch_mm() which is used by use_mm().
Arguably it is a bug in use_mm() to call switch_mm() in a different context than
it expects, but fixing that will take time.
This was discovered recently when vhost started throwing warnings such as:
BUG: sleeping function called from invalid context at kernel/mutex.c:578
in_atomic(): 0, irqs_disabled(): 1, pid: 10768, name: vhost-10760
no locks held by vhost-10760/10768.
irq event stamp: 10
hardirqs last enabled at (9): _raw_spin_unlock_irq+0x40/0x80
hardirqs last disabled at (10): switch_slb+0x2e4/0x490
softirqs last enabled at (0): copy_process+0x5e8/0x1260
softirqs last disabled at (0): (null)
Call Trace:
show_stack+0x88/0x390 (unreliable)
dump_stack+0x30/0x44
__might_sleep+0x1c4/0x2d0
mutex_lock_nested+0x74/0x5c0
cgroup_attach_task_all+0x5c/0x180
vhost_attach_cgroups_work+0x58/0x80 [vhost]
vhost_worker+0x24c/0x3d0 [vhost]
kthread+0xec/0x100
ret_from_kernel_thread+0x5c/0xd4
Prior to commit 04b96e5528ca ("vhost: lockless enqueuing") (Aug 2016) the
vhost_worker() would do a spin_unlock_irq() not long after calling use_mm(),
which had the effect of reenabling IRQs. Since that commit removed the locking
in vhost_worker() the body of the vhost_worker() loop now runs with interrupts
off causing the warnings.
This patch addresses the problem by making the powerpc code mirror the x86 code,
ie. we disable interrupts in switch_mm(), and optimise the scheduler case by
defining switch_mm_irqs_off().
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
[mpe: Flesh out/rewrite change log, add stable] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make sure to check the number of endpoints to avoid dereferencing a
NULL-pointer or accessing memory beyond the endpoint array should a
malicious device lack the expected endpoints.
Fixes: e0d3bafd0258 ("V4L/DVB (10954): Add cx231xx USB driver") Cc: Sri Deevi <Srinivasa.Deevi@conexant.com> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make sure to check the number of endpoints to avoid dereferencing a
NULL-pointer or accessing memory beyond the endpoint array should a
malicious device lack the expected endpoints.
Fixes: e0d3bafd0258 ("V4L/DVB (10954): Add cx231xx USB driver") Cc: Sri Deevi <Srinivasa.Deevi@conexant.com> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Clock should be turned off after calling s5p_mfc_init_hw() from the
watchdog worker, like it is already done in the s5p_mfc_open() which also
calls this function.
Make sure to check the number of endpoints to avoid accessing memory
beyond the endpoint array should a device lack the expected endpoints.
Note that, as far as I can tell, the gspca framework has already made
sure there is at least one endpoint in the current alternate setting so
there should be no risk for a NULL-pointer dereference here.
Fixes: b517af722860 ("V4L/DVB: gspca_konica: New gspca subdriver for
konica chipset using cams")
Cc: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Hans Verkuil <hansverk@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Interrupt routine must wake process waiting for given interrupt AFTER
updating driver's internal structures and contexts. Doing it in-between
is a serious bug. This patch moves all calls to the wake() function to
the end of the interrupt processing block to avoid potential and real
races, especially on multi-core platforms. This also fixes following issue
reported from clock core (clocks were disabled in interrupt after being
unprepared from the other place in the driver, the stack trace however
points to the different place than s5p_mfc driver because of the race):
WARNING: CPU: 1 PID: 18 at drivers/clk/clk.c:544 clk_core_unprepare+0xc8/0x108
Modules linked in:
CPU: 1 PID: 18 Comm: kworker/1:0 Not tainted 4.10.0-next-20170223-00070-g04e18bc99ab9-dirty #2154
Hardware name: SAMSUNG EXYNOS (Flattened Device Tree)
Workqueue: pm pm_runtime_work
[<c010d8b0>] (unwind_backtrace) from [<c010a534>] (show_stack+0x10/0x14)
[<c010a534>] (show_stack) from [<c033292c>] (dump_stack+0x74/0x94)
[<c033292c>] (dump_stack) from [<c011cef4>] (__warn+0xd4/0x100)
[<c011cef4>] (__warn) from [<c011cf40>] (warn_slowpath_null+0x20/0x28)
[<c011cf40>] (warn_slowpath_null) from [<c0387a84>] (clk_core_unprepare+0xc8/0x108)
[<c0387a84>] (clk_core_unprepare) from [<c0389d84>] (clk_unprepare+0x24/0x2c)
[<c0389d84>] (clk_unprepare) from [<c03d4660>] (exynos_sysmmu_suspend+0x48/0x60)
[<c03d4660>] (exynos_sysmmu_suspend) from [<c042b9b0>] (pm_generic_runtime_suspend+0x2c/0x38)
[<c042b9b0>] (pm_generic_runtime_suspend) from [<c0437580>] (genpd_runtime_suspend+0x94/0x220)
[<c0437580>] (genpd_runtime_suspend) from [<c042e240>] (__rpm_callback+0x134/0x208)
[<c042e240>] (__rpm_callback) from [<c042e334>] (rpm_callback+0x20/0x80)
[<c042e334>] (rpm_callback) from [<c042d3b8>] (rpm_suspend+0xdc/0x458)
[<c042d3b8>] (rpm_suspend) from [<c042ea24>] (pm_runtime_work+0x80/0x90)
[<c042ea24>] (pm_runtime_work) from [<c01322c4>] (process_one_work+0x120/0x318)
[<c01322c4>] (process_one_work) from [<c0132520>] (worker_thread+0x2c/0x4ac)
[<c0132520>] (worker_thread) from [<c0137ab0>] (kthread+0xfc/0x134)
[<c0137ab0>] (kthread) from [<c0107978>] (ret_from_fork+0x14/0x3c)
---[ end trace 1ead49a7bb83f0d8 ]---
Currently when the RC Core is enabled (reachable) core code located
in cec_register_adapter() attempts to populate the RC structure with
a pointer to the 'parent' passed in by the caller.
Unfortunately if the caller did not specify RC capability when calling
cec_allocate_adapter(), then there will be no RC structure to populate.
This causes a "NULL pointer dereference" error.
Fixes: f51e80804f0 ("[media] cec: pass parent device in register(), not allocate()") Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This change undo the change done by 'commit 3bec24747446
("iio: hid-sensor-trigger: Change get poll value function order to avoid
sensor properties losing after resume from S3")' as this breaks some
USB/i2c sensor hubs.
Instead of relying on HW for restoring poll and hysteresis, driver stores
and restores on resume (S3). In this way user space modified settings are
not lost for any kind of sensor hub behavior.
In this change, whenever user space modifies sampling frequency or
hysteresis driver will get the feature value from the hub and store in the
per device hid_sensor_common data structure. On resume callback from S3,
system will set the feature to sensor hub, if user space ever modified the
feature value.
Fixes: 3bec24747446 ("iio: hid-sensor-trigger: Change get poll value function order to avoid sensor properties losing after resume from S3") Reported-by: Ritesh Raj Sarraf <rrs@researchut.com> Tested-by: Ritesh Raj Sarraf <rrs@researchut.com> Tested-by: Song, Hongyan <hongyan.song@intel.com> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We should call ipxitf_put() if the copy_to_user() fails.
Reported-by: 李强 <liqiang6-s@360.cn> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add missing sanity check on the non-SuperSpeed hub-descriptor length in
order to avoid parsing and leaking two bytes of uninitialised slab data
through sysfs removable-attributes (or a compound-device debug
statement).
Note that we only make sure that the DeviceRemovable field is always
present (and specifically ignore the unused PortPwrCtrlMask field) in
order to continue support any hubs with non-compliant descriptors. As a
further safeguard, the descriptor buffer is also cleared.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Johan Hovold <johan@kernel.org> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Drop erroneous cpu_to_le32 when setting the baud rate, something which
corrupted the divisor on big-endian hosts.
Found using sparse:
warning: incorrect type in argument 1 (different base types)
expected unsigned int [unsigned] [usertype] val
got restricted __le32 [usertype] <noident>
Fixes: af2ac1a091bc ("USB: serial mct_usb232: move DMA buffers to heap") Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-By: Pete Zaitcev <zaitcev@yahoo.com> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In their infinite wisdom, and never ending quest for end user frustration,
Lenovo has decided to use new USB device IDs for the wwan modules in
their 2017 laptops. The actual hardware is still the Sierra Wireless
EM7455 or EM7430, depending on region.
Commit d8e5f0eca1e8 ("usb: musb: Fix hardirq-safe hardirq-unsafe
lock order error") caused a regression where musb keeps trying to
enable host mode with no cable connected. This seems to be caused
by the fact that now phy is enabled earlier, and we are wrongly
trying to force USB host mode on an OTG port. The errors we are
getting are "trying to suspend as a_idle while active".
For ports configured as OTG, we should not need to do anything
to try to force USB host mode on it's OTG port. Trying to force host
mode in this case just seems to completely confuse the musb state
machine.
Let's fix the issue by making musb_host_setup() attempt to force the
mode only if port_mode is configured for host mode.
Fixes: d8e5f0eca1e8 ("usb: musb: Fix hardirq-safe hardirq-unsafe lock order error") Cc: Johan Hovold <johan@kernel.org> Reported-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Reported-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Tested-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Bin Liu <b-liu@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We have one register for each EP to set the maximum packet size for both
TX and RX.
If for example an RX programming would happen before the previous TX
transfer finishes we would reset the TX packet side.
To fix this issue, only modify the TX or RX part of the register.
Fixes: 550a7375fe72 ("USB: Add MUSB and TUSB support") Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Tested-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Bin Liu <b-liu@ti.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The dwc3 driver can overwite its previous events if its top-half IRQ
handler (TH) gets invoked again before processing the events in the
cache. We see this as a hang in the file transfer and the host will
attempt to reset the device. TH gets the event count and deasserts the
interrupt line by writing DWC3_GEVNTSIZ_INTMASK to DWC3_GEVNTSIZ. If
there's a new event coming between reading the event count and interrupt
deassertion, dwc3 will lose previous pending events. More generally, we
will see 0 event count, which should not affect anything.
This shouldn't be possible in the current dwc3 implementation. However,
through testing and reading the PCIe trace, the TH occasionally still
gets invoked one more time after HW interrupt deassertion. (With PCIe
legacy interrupts, TH is called repeatedly as long as the interrupt line
is asserted). We suspect that there is a small detection delay in the
SW.
To avoid this issue, Check DWC3_EVENT_PENDING flag to determine if the
events are processed in the bottom-half IRQ handler. If not, return
IRQ_HANDLED and don't process new event.
Make sure to check for the required out endpoint to avoid dereferencing
a NULL-pointer in mce_request_packet should a malicious device lack such
an endpoint. Note that this path is hit during probe.
Fixes: 66e89522aff7 ("V4L/DVB: IR: add mceusb IR receiver driver") Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Sean Young <sean@mess.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make sure to check the number of endpoints to avoid dereferencing a
NULL-pointer or accessing memory beyond the endpoint array should a
malicious device lack the expected endpoints.
Fixes: 2a9f8b5d25be ("V4L/DVB (5206): Usbvision: set alternate interface
modification")
Add missing endianness conversion when using the USB device-descriptor
bcdDevice field to construct a firmware file name.
Fixes: 8ef80aef118e ("[IRDA]: irda-usb.c: STIR421x cleanups") Cc: Nick Fedchik <nfedchik@atlantic-link.com.ua> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
With threaded interrupts, bottom-half handlers are called with
interrupts enabled. Therefore they can't safely use spin_lock(); they
have to use spin_lock_irqsave(). Lockdep warns about a violation
occurring in xhci_irq():
=========================================================
[ INFO: possible irq lock inversion dependency detected ]
4.11.0-rc8-dbg+ #1 Not tainted
---------------------------------------------------------
swapper/7/0 just changed the state of lock:
(&(&ehci->lock)->rlock){-.-...}, at: [<ffffffffa0130a69>]
ehci_hrtimer_func+0x29/0xc0 [ehci_hcd]
but this lock took another, HARDIRQ-unsafe lock in the past:
(hcd_urb_list_lock){+.....}
and interrupts could create inverse lock ordering between them.
other info that might help us debug this:
Possible interrupt unsafe locking scenario:
platform_get_irq() returns an error code, but the xhci-plat driver
ignores it and always returns -ENODEV. This is not correct, and
prevents -EPROBE_DEFER from being propagated properly.
The wrong index into the csbases/csmasks arrays was being passed to
the function to compute the chip select sizes, which resulted in the
wrong size being computed. Address that so that the correct values are
computed and printed.
Also, redo how we calculate the number of pages in a CS row.
Reported-by: Benjamin Bennett <benbennett@gmail.com> Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com> Cc: linux-edac <linux-edac@vger.kernel.org> Link: http://lkml.kernel.org/r/1493313114-11260-1-git-send-email-Yazen.Ghannam@amd.com
[ Remove unneeded integer math comment, minor cleanups. ] Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently DAX read fault can race with write(2) in the following way:
CPU1 - write(2) CPU2 - read fault
dax_iomap_pte_fault()
->iomap_begin() - sees hole
dax_iomap_rw()
iomap_apply()
->iomap_begin - allocates blocks
dax_iomap_actor()
invalidate_inode_pages2_range()
- there's nothing to invalidate
grab_mapping_entry()
- we add zero page in the radix tree
and map it to page tables
The result is that hole page is mapped into page tables (and thus zeros
are seen in mmap) while file has data written in that place.
Fix the problem by locking exception entry before mapping blocks for the
fault. That way we are sure invalidate_inode_pages2_range() call for
racing write will either block on entry lock waiting for the fault to
finish (and unmap stale page tables after that) or read fault will see
already allocated blocks by write(2).
Fixes: 9f141d6ef6258a3a37a045842d9ba7e68f368956 Link: http://lkml.kernel.org/r/20170510085419.27601-5-jack@suse.cz Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
stat/lstat/fstatat need to pass AT_NO_AUTOMOUNT to vfs_statx() as the
pre-statx code didn't set LOOKUP_AUTOMOUNT, even though fstatat() accepted
the AT_NO_AUTOMOUNT flag.
Fixes: a528d35e8bfc ("statx: Add a system call to make enhanced file info available") Reported-by: Ian Kent <raven@themaw.net> Signed-off-by: David Howells <dhowells@redhat.com> Tested-by: Ian Kent <raven@themaw.net> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add missing endianness conversion when applying the Alea timeout quirk.
Found using sparse:
warning: restricted __le16 degrades to integer
Fixes: e4a886e811cd ("hwrng: chaoskey - Fix URB warning due to timeout on Alea") Cc: Bob Ham <bob.ham@collabora.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Keith Packard <keithp@keithp.com> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch adds support for recognition of ARM-USB-TINY(H) devices which
are almost identical to ARM-USB-OCD(H) but lacking separate barrel jack
and serial console.
By suggestion from Johan Hovold it is possible to replace
ftdi_jtag_quirk with a bit more generic construction. Since all
Olimex-ARM debuggers has exactly two ports, we could safely always use
only second port within the debugger family.
Commit 557aaa7ffab6 ("ft232: support the ASYNC_LOW_LATENCY
flag") enables unprivileged users to set the FTDI latency timer,
but there was a logic flaw that skipped sending the corresponding
USB control message to the device.
Specifically, the device latency timer would not be updated until next
open, something which was later also inadvertently broken by commit c19db4c9e49a ("USB: ftdi_sio: set device latency timeout at port
probe").
A recent commit c6dce2626606 ("USB: serial: ftdi_sio: fix extreme
low-latency setting") disabled the low-latency mode by default so we now
need this fix to allow unprivileged users to again enable it.
Signed-off-by: Anthony Mallet <anthony.mallet@laas.fr>
[johan: amend commit message] Fixes: 557aaa7ffab6 ("ft232: support the ASYNC_LOW_LATENCY flag") Fixes: c19db4c9e49a ("USB: ftdi_sio: set device latency timeout at port probe"). Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Imagine we have a pid namespace and a task from its parent's pid_ns,
which made setns() to the pid namespace. The task is doing fork(),
while the pid namespace's child reaper is dying. We have the race
between them:
Task from parent pid_ns Child reaper
copy_process() ..
alloc_pid() ..
.. zap_pid_ns_processes()
.. disable_pid_allocation()
.. read_lock(&tasklist_lock)
.. iterate over pids in pid_ns
.. kill tasks linked to pids
.. read_unlock(&tasklist_lock)
write_lock_irq(&tasklist_lock); ..
attach_pid(p, PIDTYPE_PID); ..
.. ..
So, just created task p won't receive SIGKILL signal,
and the pid namespace will be in contradictory state.
Only manual kill will help there, but does the userspace
care about this? I suppose, the most users just inject
a task into a pid namespace and wait a SIGCHLD from it.
The patch fixes the problem. It simply checks for
(pid_ns->nr_hashed & PIDNS_HASH_ADDING) in copy_process().
We do it under the tasklist_lock, and can't skip
PIDNS_HASH_ADDING as noted by Oleg:
"zap_pid_ns_processes() does disable_pid_allocation()
and then takes tasklist_lock to kill the whole namespace.
Given that copy_process() checks PIDNS_HASH_ADDING
under write_lock(tasklist) they can't race;
if copy_process() takes this lock first, the new child will
be killed, otherwise copy_process() can't miss
the change in ->nr_hashed."
If allocation is disabled, we just return -ENOMEM
like it's made for such cases in alloc_pid().
v2: Do not move disable_pid_allocation(), do not
introduce a new variable in copy_process() and simplify
the patch as suggested by Oleg Nesterov.
Account the problem with double irq enabling
found by Eric W. Biederman.
Fixes: c876ad768215 ("pidns: Stop pid allocation when init dies") Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> CC: Andrew Morton <akpm@linux-foundation.org> CC: Ingo Molnar <mingo@kernel.org> CC: Peter Zijlstra <peterz@infradead.org> CC: Oleg Nesterov <oleg@redhat.com> CC: Mike Rapoport <rppt@linux.vnet.ibm.com> CC: Michal Hocko <mhocko@suse.com> CC: Andy Lutomirski <luto@kernel.org> CC: "Eric W. Biederman" <ebiederm@xmission.com> CC: Andrei Vagin <avagin@openvz.org> CC: Cyrill Gorcunov <gorcunov@openvz.org> CC: Serge Hallyn <serge@hallyn.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The code can potentially sleep for an indefinite amount of time in
zap_pid_ns_processes triggering the hung task timeout, and increasing
the system average. This is undesirable. Sleep with a task state of
TASK_INTERRUPTIBLE instead of TASK_UNINTERRUPTIBLE to remove these
undesirable side effects.
Apparently under heavy load this has been allowing Chrome to trigger
the hung time task timeout error and cause ChromeOS to reboot.
Reported-by: Vovo Yang <vovoy@google.com> Reported-by: Guenter Roeck <linux@roeck-us.net> Tested-by: Guenter Roeck <linux@roeck-us.net> Fixes: 6347e9009104 ("pidns: guarantee that the pidns init will be the last pidns process reaped") Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The only context that frees user_exp_rcv data structures is the last
context closed (from a sub-context set). This leaks the allocations
from the other sub-contexts. Separate the common frees from the
specific frees and call them at the appropriate time.
Using KEDR to check for memory leaks we get:
Before test:
[leak_check] Possible leaks: 25
After test:
[leak_check] Possible leaks: 31 (6 leaked data structures)
After patch applied (before and after test have the same value)
[leak_check] Possible leaks: 25
Each leak is 192 + 13440 + 6720 = 20352 bytes per sub-context.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com> Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com> Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com> Signed-off-by: Doug Ledford <dledford@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When prescaler (PSC) is 0, it means div factor is 1: counter clock
frequency is equal to input clk / (PSC + 1).
When reload value is 8 for example, counter counts 9 cycles, from 0 to 8.
This is handled in frequency write routine, by writing respectively:
- prescaler - 1 to PSC
- reload value - 1 to ARR
This fix does the opposite when reading the frequency from PSC and ARR:
- prescaler is PSC + 1
- reload value is ARR + 1
Thus, PSC may be 0, depending on requested sampling frequency (div 1).
In this case, reading freq wrongly reports 0, instead of computing and
reporting correct value.
Remove test on !psc and !arr.
Small test on stm32f4 (example on tim1_trgo), before this fix:
$ cd /sys/bus/iio/devices/triggerX
$ echo 10000 > sampling_frequency
$ cat sampling_frequency
0
After this fix:
$ echo 10000 > sampling_frequency
$ cat sampling_frequency
10000
While calculating the compensation of the humidity there are negative values
interpreted as unsigned because of unsigned variables used. These values as
well as the constants need to be casted to signed as indicated by the
documentation of the sensor.
Signed-off-by: Andreas Klinger <ak@it-klinger.de> Acked-by: Linus Walleij <linus.walleij@linaro.org> Reviewed-by: Matt Ranostay <matt.ranostay@konsulko.com> Signed-off-by: Jonathan Cameron <jic23@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To select the appropriate shost template, the driver is issuing a
mailbox command to retrieve the wwn. Turns out the sending of the
command precedes the reset of the function. On SLI-4 adapters, this is
inconsequential as the mailbox command location is specified by dma via
the BMBX register. However, on SLI-3 adapters, the location of the
mailbox command submission area changes. When the function is first
powered on or reset, the cmd is submitted via PCI bar memory. Later the
driver changes the function config to use host memory and DMA. The
request to start a mailbox command is the same, a simple doorbell write,
regardless of submission area. So.. if there has not been a boot driver
run against the adapter, the mailbox command works as defaults are
ok. But, if the boot driver has configured the card and, and if no
platform pci function/slot reset occurs as the os starts, the mailbox
command will fail. The SLI-3 device will use the stale boot driver dma
location. This can cause PCI eeh errors.
Fix is to reset the sli-3 function before sending the mailbox command,
thus synchronizing the function/driver on mailbox location.
Note: The fix uses routines that are typically invoked later in the call
flow to reset the sli-3 device. The issue in using those routines is
that the normal (non-fix) flow does additional initialization, namely
the allocation of the pport structure. So, rather than significantly
reworking the initialization flow so that the pport is alloc'd first,
pointer checks are added to work around it. Checks are limited to the
routines invoked by a sli-3 adapter (s3 routines) as this fix/early call
is only invoked on a sli3 adapter. Nothing changes post the
fix. Subsequent initialization, and another adapter reset, still occur -
both on sli-3 and sli-4 adapters.
Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com> Signed-off-by: James Smart <james.smart@broadcom.com> Fixes: 96418b5e2c88 ("scsi: lpfc: Fix eh_deadline setting for sli3 adapters.") Reviewed-by: Ewan D. Milne <emilne@redhat.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver is sending a response to the actual scsi op that was
aborted by an abort task TM, while LIO is sending a response to
the abort task TM.
ibmvscsis_tgt does not send the response to the client until
release_cmd time. The reason for this was because if we did it
at queue_status time, then the client would be free to reuse the
tag for that command, but we're still using the tag until the
command is released at release_cmd time, so we chose to delay
sending the response until then. That then caused this issue, because
release_cmd is always called, even if queue_status is not.
SCSI spec says that the initiator that sends the abort task
TM NEVER gets a response to the aborted op and with the current
code it will send a response. Thus this fix will remove that response
if the CMD_T_ABORTED && !CMD_T_TAS.
Another case with a small timing window is the case where if LIO sends a
TMR_DOES_NOT_EXIST, and the release_cmd callback is called for the TMR Abort
cmd before the release_cmd for the (attemped) aborted cmd, then we need to
ensure that we send the response for the (attempted) abort cmd to the client
before we send the response for the TMR Abort cmd.
Signed-off-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com> Signed-off-by: Michael Cyr <mikecyr@linux.vnet.ibm.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The memory allocator passed to __unflatten_device_tree() (e.g. a wrapped
kzalloc) can fail so add the missing sanity check to avoid dereferencing
a NULL pointer.
Fixes: fe14042358fa ("of/flattree: Refactor unflatten_device_tree and add fdt_unflatten_tree") Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Rob Herring <robh@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The call to of_find_node_by_path("/cpus") returns the cpus device_node
with its reference count incremented. There is no matching of_node_put()
call in of_numa_parse_cpu_nodes() which results in a leaked reference
to the "/cpus" node.
This patch adds an of_node_put() to release the reference.
fixes: 298535c00a2c ("of, numa: Add NUMA of binding implementation.") Signed-off-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com> Acked-by: David Daney <david.daney@cavium.com> Signed-off-by: Rob Herring <robh@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
proc_create_mount_point() forgot to increase the parent's nlink, and
it resulted in unbalanced hard link numbers, e.g. /proc/fs shows one
less than expected.
Fixes: eb6d38d5427b ("proc: Allow creating permanently empty directories...") Reported-by: Tristan Ye <tristan.ye@suse.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix a boundary condition where in some cases an eeh event that results
in card reset isn't passed on to a driver attached to the virtual PCI
device associated with a slice. This will happen in case when a slice
attached device driver returns a value other than
PCI_ERS_RESULT_NEED_RESET from the eeh error_detected() callback. This
would result in an early return from cxl_pci_error_detected() and
other drivers attached to other AFUs on the card wont be notified.
The patch fixes this by making sure that all slice attached
device-drivers are notified and the return values from
error_detected() callback are aggregated in a scheme where request for
'disconnect' trumps all and 'none' trumps 'need_reset'.
During an eeh event when the cxl card is fenced and card sysfs attr
perst_reloads_same_image is set following warning message is seen in the
kernel logs:
Adapter context unlocked with 0 active contexts
------------[ cut here ]------------
WARNING: CPU: 12 PID: 627 at
../drivers/misc/cxl/main.c:325 cxl_adapter_context_unlock+0x60/0x80 [cxl]
Even though this warning is harmless, it clutters the kernel log
during an eeh event. This warning is triggered as the EEH callback
cxl_pci_error_detected doesn't obtain a context-lock before forcibly
detaching all active context and when context-lock is released during
call to cxl_configure_adapter from cxl_pci_slot_reset, a warning in
cxl_adapter_context_unlock is triggered.
To fix this warning, we acquire the adapter context-lock via
cxl_adapter_context_lock() in the eeh callback
cxl_pci_error_detected() once all the virtual AFU PHBs are notified
and their contexts detached. The context-lock is released in
cxl_pci_slot_reset() after the adapter is successfully reconfigured
and before the we call the slot_reset callback on slice attached
device-drivers.
Fixes: 70b565bbdb91 ("cxl: Prevent adapter reset if an active context exists") Reported-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Vaibhav Jain <vaibhav@linux.vnet.ibm.com> Acked-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Reviewed-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Tested-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
On a loaded virtualization host (dozen guests booting at the same time)
it may happen that the ohci controller emulation doesn't manage to do
timely frame processing, with the result that the io watchdog fires and
considers the controller being dead, even though it's only the emulation
being unusual slow due to the load peak.
So, add a quirk for qemu and don't use the watchdog in case we figure we
are running on emulated ohci. The virtual ohci controller masquerades
as apple ohci controller, but we can identify it by subsystem id.
Notifications may only be 8 bytes long. Accessing the 9th and
10th byte of unimplemented/unknown notifications may be insecure.
Also check the length of known notifications before accessing anything
behind the 8th byte.
omap_gpio_debounce() does not validate that the requested debounce
is within a range it can handle. Instead it lets the register value
wrap silently, and always returns success.
This can lead to all sorts of unexpected behavior, such as gpio_keys
asking for a too-long debounce, but getting a very short debounce in
practice.
Fix this by returning -EINVAL if the requested value does not fit into
the register field. If there is no debounce clock available at all,
return -ENOTSUPP.
The idea here was to avoid having to "manually" program the HW if there's
a new earliest alarm. This was lazy and bad, as it leads to loads of fun
races between inter-related callers (ie. therm).
Turns out, it's not so difficult after all. Go figure ;)
Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This "optimisation" (which was originally meant to skip updating cursor
settings in the core channel on position-only updates) turned out to be
pointless in the final design of the code before it was merged.
Remove it completely, as it breaks other cases.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
At dot clocks > approx. 250 Mhz, some of these calcs will overflow and
cause miscalculation of latency watermarks, and for some overflows also
divide-by-zero driver crash ("divide error: 0000 [#1] PREEMPT SMP" in
"dce_v10_0_latency_watermark+0x12d/0x190").
This zero-divide happened, e.g., on AMD Tonga Pro under DCE-10,
on a Displayport panel when trying to set a video mode of 2560x1440
at 165 Hz vrefresh with a dot clock of 635.540 Mhz.
Refine calculations to avoid the overflows.
Tested for DCE-10 with R9 380 Tonga + ASUS ROG PG279 panel.
Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Avoid big roundoff errors in scanline/hactive durations for
high pixel clocks, especially for >= 500 Mhz, and thereby
program more accurate display fifo watermarks.
Implemented here for DCE 6,8,10,11.
Successfully tested on DCE 10 with AMD R9 380 Tonga.
Reviewed-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Make sure to check the number of endpoints to avoid dereferencing a
NULL-pointer or accessing memory beyond the endpoint array should a
malicious device lack the expected endpoints.
Fixes: 36bcce430657 ("ath9k_htc: Handle storage devices") Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
git commit c5328901aa1db134 "[S390] entry[64].S improvements" removed
the update of the exit_timer lowcore field from the critical section
cleanup of the .Lsysc_restore/.Lsysc_done and .Lio_restore/.Lio_done
blocks. If the PSW is updated by the critical section cleanup to point to
user space again, the interrupt entry code will do a vtime calculation
after the cleanup completed with an exit_timer value which has *not* been
updated. Due to this incorrect system time deltas are calculated.
If an interrupt occured with an old PSW between .Lsysc_restore/.Lsysc_done
or .Lio_restore/.Lio_done update __LC_EXIT_TIMER with the system entry
time of the interrupt.
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since linux v3.14 with commit 38dfac843cb6d7be1 ("vmcore: prevent PT_NOTE
p_memsz overflow during header update") on s390 we get the following
message in the kdump kernel:
The reason for this is that we don't create a final zero note in
the ELF header which the proc/vmcore code uses to find out the end
of the notes section (see also kernel/kexec_core.c:final_note()).
It still worked on s390 by chance because we (most of the time?) have the
byte pattern 0x6b6b6b6b after the notes section which also makes the notes
parsing code stop in update_note_header_size_elf64() because 0x6b6b6b6b is
interpreded as note size:
if ((real_sz + sz) > max_sz) {
pr_warn("Warning: Exceeded p_memsz, dropping P ...);
break;
}
So fix this and add the missing final note to the ELF header.
We don't have to adjust the memory size for ELF header ("alloc_size")
because the new ELF note still fits into the 0x1000 base memory.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 43530b69d758328d3ffe6ab98fd640463e8e3667 ("regulator: Use
regmap_read/write(), regmap_update_bits functions directly") intended
to replace working inline helper functions with standard regmap
calls. However, it also inverted the set/clear logic of the "CORE ADJ
Allowed" bit. That patch was clearly never tested, since without that
bit cleared, the core VDCDC1 voltage output does not react to I2C
configuration changes.
This patch fixes the issue by clearing the bit as in the original,
correct implementation. Note for stable back porting that, due to
subsequent driver churn, this patch will not apply on every kernel
version.
Fixes: 43530b69d758 ("regulator: Use regmap_read/write(), regmap_update_bits functions directly") Signed-off-by: Richard Cochran <rcochran@linutronix.de> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The code to fetch a 64-bit value from user space was entirely buggered,
and has been since the code was merged in early 2016 in commit b2f680380ddf ("x86/mm/32: Add support for 64-bit __get_user() on 32-bit
kernels").
Happily the buggered routine is almost certainly entirely unused, since
the normal way to access user space memory is just with the non-inlined
"get_user()", and the inlined version didn't even historically exist.
The normal "get_user()" case is handled by external hand-written asm in
arch/x86/lib/getuser.S that doesn't have either of these issues.
There were two independent bugs in __get_user_asm_u64():
- it still did the STAC/CLAC user space access marking, even though
that is now done by the wrapper macros, see commit 11f1a4b9755f
("x86: reorganize SMAP handling in user space accesses").
This didn't result in a semantic error, it just means that the
inlined optimized version was hugely less efficient than the
allegedly slower standard version, since the CLAC/STAC overhead is
quite high on modern Intel CPU's.
- the double register %eax/%edx was marked as an output, but the %eax
part of it was touched early in the asm, and could thus clobber other
inputs to the asm that gcc didn't expect it to touch.
In particular, that meant that the generated code could look like
this:
mov (%eax),%eax
mov 0x4(%eax),%edx
where the load of %edx obviously was _supposed_ to be from the 32-bit
word that followed the source of %eax, but because %eax was
overwritten by the first instruction, the source of %edx was
basically random garbage.
The fixes are trivial: remove the extraneous STAC/CLAC entries, and mark
the 64-bit output as early-clobber to let gcc know that no inputs should
alias with the output register.
Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Benjamin LaHaise <bcrl@kvack.org> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Huawei folks reported a read out-of-bounds vulnerability in kvm pio emulation.
- "inb" instruction to access PIT Mod/Command register (ioport 0x43, write only,
a read should be ignored) in guest can get a random number.
- "rep insb" instruction to access PIT register port 0x43 can control memcpy()
in emulator_pio_in_emulated() to copy max 0x400 bytes but only read 1 bytes,
which will disclose the unimportant kernel memory in host but no crash.
The similar test program below can reproduce the read out-of-bounds vulnerability:
void hexdump(void *mem, unsigned int len)
{
unsigned int i, j;
The vcpu->arch.pio_data buffer is used by both in/out instrutions emulation
w/o clear after using which results in some random datas are left over in
the buffer. Guest reads port 0x43 will be ignored since it is write only,
however, the function kernel_pio() can't distigush this ignore from successfully
reads data from device's ioport. There is no new data fill the buffer from
port 0x43, however, emulator_pio_in_emulated() will copy the stale data in
the buffer to the guest unconditionally. This patch fixes it by clearing the
buffer before in instruction emulation to avoid to grant guest the stale data
in the buffer.
In addition, string I/O is not supported for in kernel device. So there is no
iteration to read ioport %RCX times for string I/O. The function kernel_pio()
just reads one round, and then copy the io size * %RCX to the guest unconditionally,
actually it copies the one round ioport data w/ other random datas which are left
over in the vcpu->arch.pio_data buffer to the guest. This patch fixes it by
introducing the string I/O support for in kernel device in order to grant the right
ioport datas to the guest.
Before the patch:
0x000000: fe 38 93 93 ff ff ab ab .8......
0x000008: ab ab ab ab ab ab ab ab ........
0x000010: ab ab ab ab ab ab ab ab ........
0x000018: ab ab ab ab ab ab ab ab ........
0x000020: ab ab ab ab ab ab ab ab ........
0x000028: ab ab ab ab ab ab ab ab ........
0x000030: ab ab ab ab ab ab ab ab ........
0x000038: ab ab ab ab ab ab ab ab ........
0x000000: f6 00 00 00 00 00 00 00 ........
0x000008: 00 00 00 00 00 00 00 00 ........
0x000010: 00 00 00 00 4d 51 30 30 ....MQ00
0x000018: 30 30 20 33 20 20 20 20 00 3
0x000020: ab ab ab ab ab ab ab ab ........
0x000028: ab ab ab ab ab ab ab ab ........
0x000030: ab ab ab ab ab ab ab ab ........
0x000038: ab ab ab ab ab ab ab ab ........
0x000000: f6 00 00 00 00 00 00 00 ........
0x000008: 00 00 00 00 00 00 00 00 ........
0x000010: 00 00 00 00 4d 51 30 30 ....MQ00
0x000018: 30 30 20 33 20 20 20 20 00 3
0x000020: ab ab ab ab ab ab ab ab ........
0x000028: ab ab ab ab ab ab ab ab ........
0x000030: ab ab ab ab ab ab ab ab ........
0x000038: ab ab ab ab ab ab ab ab ........
After the patch:
0x000000: 1e 02 f8 00 ff ff ab ab ........
0x000008: ab ab ab ab ab ab ab ab ........
0x000010: ab ab ab ab ab ab ab ab ........
0x000018: ab ab ab ab ab ab ab ab ........
0x000020: ab ab ab ab ab ab ab ab ........
0x000028: ab ab ab ab ab ab ab ab ........
0x000030: ab ab ab ab ab ab ab ab ........
0x000038: ab ab ab ab ab ab ab ab ........
0x000000: d2 e2 d2 df d2 db d2 d7 ........
0x000008: d2 d3 d2 cf d2 cb d2 c7 ........
0x000010: d2 c4 d2 c0 d2 bc d2 b8 ........
0x000018: d2 b4 d2 b0 d2 ac d2 a8 ........
0x000020: ab ab ab ab ab ab ab ab ........
0x000028: ab ab ab ab ab ab ab ab ........
0x000030: ab ab ab ab ab ab ab ab ........
0x000038: ab ab ab ab ab ab ab ab ........
0x000000: 00 00 00 00 00 00 00 00 ........
0x000008: 00 00 00 00 00 00 00 00 ........
0x000010: 00 00 00 00 00 00 00 00 ........
0x000018: 00 00 00 00 00 00 00 00 ........
0x000020: ab ab ab ab ab ab ab ab ........
0x000028: ab ab ab ab ab ab ab ab ........
0x000030: ab ab ab ab ab ab ab ab ........
0x000038: ab ab ab ab ab ab ab ab ........
This can be reproduced by run kvm-unit-tests/hyperv_stimer.flat w/
CONFIG_PREEMPT and CONFIG_DEBUG_PREEMPT enabled.
Safe access to per-CPU data requires a couple of constraints, though: the
thread working with the data cannot be preempted and it cannot be migrated
while it manipulates per-CPU variables. If the thread is preempted, the
thread that replaces it could try to work with the same variables; migration
to another CPU could also cause confusion. However there is no preemption
disable when reads host per-CPU tsc rate to calculate the current kvmclock
timestamp.
This patch fixes it by utilizing get_cpu/put_cpu pair to guarantee both
__this_cpu_read() and rdtsc() are not preempted.
Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
SDM mentioned that "The MXCSR has several reserved bits, and attempting to write
a 1 to any of these bits will cause a general-protection exception(#GP) to be
generated". The syzkaller forks' testcase overrides xsave area w/ random values
and steps on the reserved bits of MXCSR register. The damaged MXCSR register
values of guest will be restored to SSEx MXCSR register before vmentry. This
patch fixes it by catching userspace override MXCSR register reserved bits w/
random values and bails out immediately.
Reported-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Modifying the attributes of a file makes ima_inode_post_setattr reset
the IMA cache flags. So if the file, which has just been created,
is opened a second time before the first file descriptor is closed,
verification fails since the security.ima xattr has not been written
yet. We therefore have to look at the IMA_NEW_FILE even if the file
already existed.
With this patch there should no longer be an error when cat tries to
open testfile:
Command buffers (skb's) are allocated by the main driver, and freed upon
the last use. That last use is often in mwifiex_free_cmd_buffer(). In
the meantime, if the command buffer gets used by the PCI driver, we map
it as DMA-able, and store the mapping information in the 'cb' memory.
However, if a command was in-flight when resetting the device (and
therefore was still mapped), we don't get a chance to unmap this memory
until after the core has cleaned up its command handling.
Let's keep a refcount within the PCI driver, so we ensure the memory
only gets freed after we've finished unmapping it.
Noticed by KASAN when forcing a reset via:
echo 1 > /sys/bus/pci/.../reset
The same code path can presumably be exercised in remove() and
shutdown().
This bug has been around in different forms for a while. It was sort of
noticed in commit 955ab095c51a ("mwifiex: Do not kfree cmd buf while
unregistering PCIe"), but it just fixed the double-free, without
acknowledging the potential for use-after-free.
Fixes: fc3314609047 ("mwifiex: use pci_alloc/free_consistent APIs for PCIe") Signed-off-by: Brian Norris <briannorris@chromium.org> Signed-off-by: Kalle Valo <kvalo@codeaurora.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
nl80211 provides the NL80211_SCAN_FLAG_RANDOM_ADDR for every scan
request that should be randomized; the absence of such a flag means we
should not randomize. However, mwifiex was stashing the latest
randomization request and *always* using it for future scans, even those
that didn't set the flag.
Let's zero out the randomization info whenever we get a scan request
without NL80211_SCAN_FLAG_RANDOM_ADDR. I'd prefer to remove
priv->random_mac entirely (and plumb the randomization MAC properly
through the call sequence), but the spaghetti is a little difficult to
unravel here for me.
Fixes: c2a8f0ff9c6c ("mwifiex: support random MAC address for scanning") Signed-off-by: Brian Norris <briannorris@chromium.org> Signed-off-by: Kalle Valo <kvalo@codeaurora.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
if called md_set_readonly and set MD_CLOSING bit, the mddev cannot
be opened any more due to the MD_CLOING bit wasn't cleared. Thus it
needs to be cleared in md_ioctl after any call to md_set_readonly()
or do_md_stop().
Signed-off-by: NeilBrown <neilb@suse.com> Fixes: af8d8e6f0315 ("md: changes for MD_STILL_CLOSED flag") Signed-off-by: Zhilong Liu <zlliu@suse.com> Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When growing raid5 device on machine with small memory, there is chance that
mdadm will be killed and the following bug report can be observed. The same
bug could also be reproduced in linux-4.10.6.
The problem is that resize_stripes() releases new stripe_heads before assigning new
slab cache to conf->slab_cache. If the shrinker function raid5_cache_scan() gets called
after resize_stripes() starting releasing new stripes but right before new slab cache
being assigned, it is possible that these new stripe_heads will be freed with the old
slab_cache which was already been destoryed and that triggers this bug.
Signed-off-by: Dennis Yang <dennisyang@qnap.com> Fixes: edbe83ab4c27 ("md/raid5: allow the stripe_cache to grow and shrink.") Reviewed-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>