Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

SEGV_PKUERR is a signal specific si_code which happens to have the
same numeric value as several others: BUS_MCEERR_AR, ILL_ILLTRP,
FPE_FLTOVF, TRAP_HWBKPT, CLD_TRAPPED, POLL_ERR, SEGV_THREAD_ID,
as such it is not safe to just test the si_code the signal number
must also be tested to prevent a false positive in fill_sig_info_pkey.

I found this error by inspection, and BUS_MCEERR_AR appears to
be a real candidate for confusion.  So pass in si_signo and fix it.

Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Fixes: 019132ff ("x86/mm/pkeys: Fill in pkey field in siginfo")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Setting si_code to 0 is the same a setting si_code to SI_USER which is definitely
not correct.  With si_code set to SI_USER si_pid and si_uid will be copied to
userspace instead of si_addr.  Which is very wrong.

So fix this by using a sensible si_code (SEGV_MAPERR) for this failure.

Cc: stable@vger.kernel.org
Fixes: b920de1b ("mn10300: add the MN10300/AM33 architecture to the kernel")
Cc: David Howells <dhowells@redhat.com>
Cc: Masakazu Urade <urade.masakazu@jp.panasonic.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Call clear_siginfo to ensure stack allocated siginfos are fully
initialized before being passed to the signal sending functions.

This ensures that if there is the kind of confusion documented by
TRAP_FIXME, FPE_FIXME, or BUS_FIXME the kernel won't send unitialized
data to userspace when the kernel generates a signal with SI_USER but
the copy to userspace assumes it is a different kind of signal, and
different fields are initialized.

This also prepares the way for turning copy_siginfo_to_user
into a copy_to_user, by removing the need in many cases to perform
a field by field copy simply to skip the uninitialized fields.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Unfortunately struct siginfo has holes both in the common part of the
structure, in the union members, and in the lack of padding of the
union members.  The result of those wholes is that the C standard does
not guarantee those bits will be initialized.  As struct siginfo is
for communication between the kernel and userspace that is a problem.

Add the helper function clear_siginfo that is guaranteed to clear all of
the bits in struct siginfo so when the structure is copied there is no danger
of copying old kernel data and causing a leak of information from kernel
space to userspace.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

The savings for copying just part of struct siginfo appears to be in the
noise on modern machines.  So remove this ``optimization'' and simplify the code.

At the same time mark the second parameter as constant so there is no confusion
as to which direction the copy will go.

This ensures that a fully initialized siginfo that is sent ends up as
a fully initialized siginfo on the signal queue.  This full initialization
ensures even confused code won't copy unitialized data to userspace, and
it prepares for turning copy_siginfo_to_user into a simple copy_to_user.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Setting si_code to 0 results in a userspace seeing an si_code of 0.
This is the same si_code as SI_USER.  Posix and common sense requires
that SI_USER not be a signal specific si_code.  As such this use of 0
for the si_code is a pretty horribly broken ABI.

Further use of si_code == 0 guaranteed that copy_siginfo_to_user saw a
value of __SI_KILL and now sees a value of SIL_KILL with the result
that uid and pid fields are copied and which might copying the si_addr
field by accident but certainly not by design.  Making this a very
flakey implementation.

Utilizing FPE_FIXME, siginfo_layout will now return SIL_FAULT and the
appropriate fields will be reliably copied.

Possible ABI fixes includee:
- Send the signal without siginfo
- Don't generate a signal
- Possibly assign and use an appropriate si_code
- Don't handle cases which can't happen

Cc: Russell King <rmk@flint.arm.linux.org.uk>
Cc: linux-arm-kernel@lists.infradead.org
Ref: 451436b7 ("[ARM] Add support code for ARM hardware vector floating point")
History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.gitSigned-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Setting si_code to 0 results in a userspace seeing an si_code of 0.
This is the same si_code as SI_USER.  Posix and common sense requires
that SI_USER not be a signal specific si_code.  As such this use of 0
for the si_code is a pretty horribly broken ABI.

Further use of si_code == 0 guaranteed that copy_siginfo_to_user saw a
value of __SI_KILL and now sees a value of SIL_KILL with the result
that uid and pid fields are copied and which might copying the si_addr
field by accident but certainly not by design.  Making this a very
flakey implementation.

Utilizing FPE_FIXME, BUS_FIXME, TRAP_FIXME siginfo_layout will now return
SIL_FAULT and the appropriate fields will be reliably copied.

But folks this is a new and unique kind of bad.  This is massively
untested code bad.  This is inventing new and unique was to get
siginfo wrong bad.  This is don't even think about Posix or what
siginfo means bad.  This is lots of eyeballs all missing the fact
that the code does the wrong thing bad.  This is getting stuck
and keep making the same mistake bad.

I really hope we can find a non userspace breaking fix for this on a
port as new as arm64.

Possible ABI fixes include:
- Send the signal without siginfo
- Don't generate a signal
- Possibly assign and use an appropriate si_code
- Don't handle cases which can't happen

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Tyler Baicar <tbaicar@codeaurora.org>
Cc: James Morse <james.morse@arm.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Nicolas Pitre <nico@linaro.org>
Cc: Olof Johansson <olof@lixom.net>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-arm-kernel@lists.infradead.org
Ref: 53631b54 ("arm64: Floating point and SIMD")
Ref: 32015c23 ("arm64: exception: handle Synchronous External Abort")
Ref: 1d18c47c ("arm64: MMU fault handling and page table management")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Setting si_code to 0 results in a userspace seeing an si_code of 0.
This is the same si_code as SI_USER.  Posix and common sense requires
that SI_USER not be a signal specific si_code.  As such this use of 0
for the si_code is a pretty horribly broken ABI.

Further use of si_code == 0 guaranteed that copy_siginfo_to_user saw a
value of __SI_KILL and now sees a value of SIL_KILL with the result
that uid and pid fields are copied and which might copying the si_addr
field by accident but certainly not by design.  Making this a very
flakey implementation.

Utilizing FPE_FIXME and TRAP_FIXME, siginfo_layout() will now return
SIL_FAULT and the appropriate fields will be reliably copied.

Possible ABI fixes includee:
- Send the signal without siginfo
- Don't generate a signal
- Possibly assign and use an appropriate si_code
- Don't handle cases which can't happen
Cc: Paul Mackerras <paulus@samba.org>
Cc: Kumar Gala <kumar.gala@freescale.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc:  linuxppc-dev@lists.ozlabs.org
Ref: 9bad068c ("[PATCH] ppc32: support for e500 and 85xx")
Ref: 0ed70f61 ("PPC32: Provide proper siginfo information on various exceptions.")
History Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.gitSigned-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Setting si_code to 0 results in a userspace seeing an si_code of 0.
This is the same si_code as SI_USER.  Posix and common sense requires
that SI_USER not be a signal specific si_code.  As such this use of 0
for the si_code is a pretty horribly broken ABI.

Further use of si_code == 0 guaranteed that copy_siginfo_to_user saw a
value of __SI_KILL and now sees a value of SIL_KILL with the result
hat uid and pid fields are copied and which might copying the si_addr
field by accident but certainly not by design.  Making this a very
flakey implementation.

Utilizing FPE_FIXME siginfo_layout will now return SIL_FAULT and the
appropriate fields will reliably be copied.

Possible ABI fixes includee:
  - Send the signal without siginfo
  - Don't generate a signal
  - Possibly assign and use an appropriate si_code
  - Don't handle cases which can't happen

Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-metag@vger.kernel.org
Ref: ac919f08 ("metag: Traps")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Setting si_code to 0 results in a userspace seeing an si_code of 0.
This is the same si_code as SI_USER.  Posix and common sense requires
that SI_USER not be a signal specific si_code.  As such this use of 0
for the si_code is a pretty horribly broken ABI.

Further use of si_code == 0 guaranteed that copy_siginfo_to_user saw a
value of __SI_KILL and now sees a value of SIL_KILL with the result
that uid and pid fields are copied and which might copying the si_addr
field by accident but certainly not by design.  Making this a very
flakey implementation.

Utilizing FPE_FIXME siginfo_layout will now return SIL_FAULT and the
appropriate fields will reliably be copied.

This bug is 13 years old and parsic machines are no longer being built
so I don't know if it possible or worth fixing it.  But it is at least
worth documenting this so other architectures don't make the same
mistake.

Possible ABI fixes includee:
  - Send the signal without siginfo
  - Don't generate a signal
  - Possibly assign and use an appropriate si_code
  - Don't handle cases which can't happen

Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: linux-parisc@vger.kernel.org
Ref: 313c01d3 ("[PATCH] PA-RISC update for 2.6.0")
Histroy Tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.gitSigned-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

While reviewing the signal sending on openrisc the do_unaligned_access
function stood out because it is obviously wrong.  A comment about an
si_code set above when actually si_code is never set.  Leading to a
random si_code being sent to userspace in the event of an unaligned
access.

Looking further SIGBUS BUS_ADRALN is the proper pair of signal and
si_code to send for an unaligned access. That is what other
architectures do and what is required by posix.

Given that do_unaligned_access is broken in a way that no one can be
relying on it on openrisc fix the code to just do the right thing.

Cc: stable@vger.kernel.org
Fixes: 769a8a96 ("OpenRISC: Traps")
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: openrisc@lists.librecores.org
Acked-by: Stafford Horne <shorne@gmail.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

Set si_signo.

Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: linux-sh@vger.kernel.org
Cc: stable@vger.kernel.org
Fixes: 0983b318 ("sh: Wire up division and address error exceptions on SH-2A.")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>

- Rename from kdb_send_sig_info to kdb_send_sig
  As there is no meaningful siginfo sent

- Use SEND_SIG_PRIV instead of generating a siginfo for a kdb
  signal.  The generated siginfo had a bogus rationale and was
  not correct in the face of pid namespaces.  SEND_SIG_PRIV
  is simpler and actually correct.

- As the code grabs siglock just send the signal with siglock
  held instead of dropping siglock and attempting to grab it again.

- Move the sig_valid test into kdb_kill where it can generate
  a good error message.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

Pull x86 fixes from Thomas Gleixner:
 "A couple of fixlets for x86:

   - Fix the ESPFIX double fault handling for 5-level pagetables

   - Fix the commandline parsing for 'apic=' on 32bit systems and update
     documentation

   - Make zombie stack traces reliable

   - Fix kexec with stack canary

   - Fix the delivery mode for APICs which was missed when the x86
     vector management was converted to single target delivery. Caused a
     regression due to the broken hardware which ignores affinity
     settings in lowest prio delivery mode.

   - Unbreak modules when AMD memory encryption is enabled

   - Remove an unused parameter of prepare_switch_to"

* 'x86/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/apic: Switch all APICs to Fixed delivery mode
  x86/apic: Update the 'apic=' description of setting APIC driver
  x86/apic: Avoid wrong warning when parsing 'apic=' in X86-32 case
  x86-32: Fix kexec with stack canary (CONFIG_CC_STACKPROTECTOR)
  x86: Remove unused parameter of prepare_switch_to
  x86/stacktrace: Make zombie stack traces reliable
  x86/mm: Unbreak modules that use the DMA API
  x86/build: Make isoimage work on Debian
  x86/espfix/64: Fix espfix double-fault handling on 5-level systems

Pull x86 page table isolation fixes from Thomas Gleixner:
 "Four patches addressing the PTI fallout as discussed and debugged
  yesterday:

   - Remove stale and pointless TLB flush invocations from the hotplug
     code

   - Remove stale preempt_disable/enable from __native_flush_tlb()

   - Plug the memory leak in the write_ldt() error path"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/ldt: Make LDT pgtable free conditional
  x86/ldt: Plug memory leak in error path
  x86/mm: Remove preempt_disable/enable() from __native_flush_tlb()
  x86/smpboot: Remove stale TLB flush invocations

Pull timer fixes from Thomas Gleixner:
 "A pile of fixes for long standing issues with the timer wheel and the
  NOHZ code:

   - Prevent timer base confusion accross the nohz switch, which can
     cause unlocked access and data corruption

   - Reinitialize the stale base clock on cpu hotplug to prevent subtle
     side effects including rollovers on 32bit

   - Prevent an interrupt storm when the timer softirq is already
     pending caused by tick_nohz_stop_sched_tick()

   - Move the timer start tracepoint to a place where it actually makes
     sense

   - Add documentation to timerqueue functions as they caused confusion
     several times now"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timerqueue: Document return values of timerqueue_add/del()
  timers: Invoke timer_start_debug() where it makes sense
  nohz: Prevent a timer interrupt storm in tick_nohz_stop_sched_tick()
  timers: Reinitialize per cpu bases on hotplug
  timers: Use deferrable base independent of base::nohz_active

Pull smp fixlet from Thomas Gleixner:
 "A trivial build warning fix for newer compilers"

* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  cpu/hotplug: Move inline keyword at the beginning of declaration

Pull scheduler fixes from Thomas Gleixner:
 "Three patches addressing the fallout of the CPU_ISOLATION changes
  especially with NO_HZ_FULL plus documentation of boot parameter
  dependency"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/isolation: Document boot parameters dependency on CONFIG_CPU_ISOLATION=y
  sched/isolation: Enable CONFIG_CPU_ISOLATION=y by default
  sched/isolation: Make CONFIG_NO_HZ_FULL select CONFIG_CPU_ISOLATION

Pull perf fixes from Thomas Gleixner:

 - plug a memory leak in the intel pmu init code

 - clang fixes

 - tooling fix to avoid including kernel headers

 - a fix for jvmti to generate correct debug information for inlined
   code

 - replace backtick with a regular shell function

 - fix the build in hardened environments

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel: Plug memory leak in intel_pmu_init()
  x86/asm: Allow again using asm.h when building for the 'bpf' clang target
  tools arch s390: Do not include header files from the kernel sources
  perf jvmti: Generate correct debug information for inlined code
  perf tools: Fix up build in hardened environments
  perf tools: Use shell function for perl cflags retrieval

Pull irq fixes from Thomas Gleixner:
 "A rather large update after the kaisered maintainer finally found time
  to handle regression reports.

   - The larger part addresses a regression caused by the x86 vector
     management rework.

     The reservation based model does not work reliably for MSI
     interrupts, if they cannot be masked (yes, yet another hw
     engineering trainwreck). The reason is that the reservation mode
     assigns a dummy vector when the interrupt is allocated and switches
     to a real vector when the interrupt is requested.

     If the MSI entry cannot be masked then the initialization might
     raise an interrupt before the interrupt is requested, which ends up
     as spurious interrupt and causes device malfunction and worse. The
     fix is to exclude MSI interrupts which do not support masking from
     reservation mode and assign a real vector right away.

   - Extend the extra lockdep class setup for nested interrupts with a
     class for the recently added irq_desc::request_mutex so lockdep can
     differeniate and does not emit false positive warnings.

   - A ratelimit guard for the bad irq printout so in case a bad irq
     comes back immediately the system does not drown in dmesg spam"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  genirq/msi, x86/vector: Prevent reservation mode for non maskable MSI
  genirq/irqdomain: Rename early argument of irq_domain_activate_irq()
  x86/vector: Use IRQD_CAN_RESERVE flag
  genirq: Introduce IRQD_CAN_RESERVE flag
  genirq/msi: Handle reactivation only on success
  gpio: brcmstb: Make really use of the new lockdep class
  genirq: Guard handle_bad_irq log messages
  kernel/irq: Extend lockdep class for request mutex

Pull objtool fixes from Thomas Gleixner:
 "Three fixlets for objtool:

   - Address two segfaults related to missing parameter and clang
     objects

   - Make it compile clean with clang"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  objtool: Fix seg fault with clang-compiled objects
  objtool: Fix seg fault caused by missing parameter
  objtool: Fix Clang enum conversion warning

Pull char/misc fixes from Greg KH:
 "Here are six small fixes of some of the char/misc drivers that have
  been sent in to resolve reported issues.

  Nothing major, a binder use-after-free fix, some thunderbolt bugfixes,
  a hyper-v bugfix, and an nvmem driver fix. All of these have been in
  linux-next with no reported issues for a while"

* tag 'char-misc-4.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  nvmem: meson-mx-efuse: fix reading from an offset other than 0
  binder: fix proc->files use-after-free
  vmbus: unregister device_obj->channels_kset
  thunderbolt: Mask ring interrupt properly when polling starts
  MAINTAINERS: Add thunderbolt.rst to the Thunderbolt driver entry
  thunderbolt: Make pathname to force_power shorter

Merge tag 'driver-core-4.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core fixes from Greg KH:
 "Here are two driver core fixes for 4.15-rc6, resolving some reported
  issues.

  The first is a cacheinfo fix for DT based systems to resolve a
  reported issue that has been around for a while, and the other is to
  resolve a regression in the kobject uevent code that showed up in
  4.15-rc1.

  Both have been in linux-next for a while with no reported issues"

* tag 'driver-core-4.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  kobject: fix suppressing modalias in uevents delivered over netlink
  drivers: base: cacheinfo: fix cache type for non-architected system cache

Pull staging fixes from Greg KH:
 "Here are three staging driver fixes for 4.15-rc6

  The first resolves a bug in the lustre driver that came about due to a
  broken cleanup patch, due to crazy list usage in that codebase.

  The remaining two are ion driver fixes, finally getting the CMA
  interaction to work properly, resolving two regressions in that area
  of the code.

  All have been in linux-next with no reported issues for a while"

* tag 'staging-4.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: android: ion: Fix dma direction for dma_sync_sg_for_cpu/device
  staging: ion: Fix ion_cma_heap allocations
  staging: lustre: lnet: Fix recent breakage from list_for_each conversion

Pull TTY fix from Greg KH:
 "Here is a single tty fix for a reported issue that you wrote the patch
  for :)

  It's been in linux-next for a week or so with no reported issues"

* tag 'tty-4.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  n_tty: fix EXTPROC vs ICANON interaction with TIOCINQ (aka FIONREAD)

Pull USB/PHY fixes from Greg KH:
 "Here are a number of small USB and PHY driver fixes for 4.15-rc6.

  Nothing major, but there are a number of regression fixes in here that
  resolve issues that have been reported a bunch. There are also the
  usual xhci fixes as well as a number of new usb serial device ids.

  All of these have been in linux-next for a while with no reported
  issues"

* tag 'usb-4.15-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usb: xhci: Add XHCI_TRUST_TX_LENGTH for Renesas uPD720201
  xhci: Fix use-after-free in xhci debugfs
  xhci: Fix xhci debugfs NULL pointer dereference in resume from hibernate
  USB: serial: ftdi_sio: add id for Airbus DS P8GR
  usb: Add device quirk for Logitech HD Pro Webcam C925e
  usb: add RESET_RESUME for ELSA MicroLink 56K
  usbip: fix usbip bind writing random string after command in match_busid
  usbip: stub_rx: fix static checker warning on unnecessary checks
  usbip: prevent leaking socket pointer address in messages
  usbip: stub: stop printing kernel pointer addresses in messages
  usbip: vhci: stop printing kernel pointer addresses in messages
  USB: Fix off by one in type-specific length check of BOS SSP capability
  USB: serial: option: adding support for YUGA CLM920-NC5
  phy: rcar-gen3-usb2: select USB_COMMON
  phy: rockchip-typec: add pm_runtime_disable in err case
  phy: cpcap-usb: Fix platform_get_irq_byname's error checking.
  phy: tegra: fix device-tree node lookups
  USB: serial: qcserial: add Sierra Wireless EM7565
  USB: serial: option: add support for Telit ME910 PID 0x1101
  USB: chipidea: msm: fix ulpi-node lookup

The blackfin architecture has seen no maintainer action of any kind since
April 2015.  No new code, no pull requests, no acks to patches, no response
to mails, nothing.

The web site has an expired certificate (expiration Sep 2017, issued in
2013), the mailing list sees no answers either, with one exception:

  https://sourceforge.net/p/adi-buildroot/mailman/adi-buildroot-devel/
  >
  > Steven is no longer working on this for ADI. Acked by me if this works. Thanks.
  >
  > Best regards,
  > Aaron Wu
  > Analog Devices Inc.

But, Aaron doesn't seem to respond to queries either.
Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull sparc bugfix from David Miller.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc64: repair calling incorrect hweight function from stubs

Andy prefers to be paranoid about the pagetable free in the error path of
write_ldt(). Make it conditional and warn whenever the installment of a
secondary LDT fails.
Requested-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

The error path in write_ldt() tries to free 'old_ldt' instead of the newly
allocated 'new_ldt', resulting in a memory leak. It also misses to clean up a
half populated LDT pagetable, which is not a leak as it gets cleaned up
when the process exits.

Free both the potentially half populated LDT pagetable and the newly
allocated LDT struct. This can be done unconditionally because once an LDT
is mapped subsequent maps will succeed, because the PTE page is already
populated and the two LDTs fit into that single page.
Reported-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linuxfoundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: f55f0501 ("x86/pti: Put the LDT in its own PGD if PTI is on")
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1712311121340.1899@nanosSigned-off-by: Ingo Molnar <mingo@kernel.org>

The preempt_disable/enable() pair in __native_flush_tlb() was added in
commit:

  5cf0791d ("x86/mm: Disable preemption during CR3 read+write")

... to protect the UP variant of flush_tlb_mm_range().

That preempt_disable/enable() pair should have been added to the UP variant
of flush_tlb_mm_range() instead.

The UP variant was removed with commit:

  ce4a4e56 ("x86/mm: Remove the UP asm/tlbflush.h code, always use the (formerly) SMP code")

... but the preempt_disable/enable() pair stayed around.

The latest change to __native_flush_tlb() in commit:

  6fd166aa ("x86/mm: Use/Fix PCID to optimize user/kernel switches")

... added an access to a per CPU variable outside the preempt disabled
regions, which makes no sense at all. __native_flush_tlb() must always
be called with at least preemption disabled.

Remove the preempt_disable/enable() pair and add a WARN_ON_ONCE() to catch
bad callers independent of the smp_processor_id() debugging.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linuxfoundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20171230211829.679325424@linutronix.deSigned-off-by: Ingo Molnar <mingo@kernel.org>

smpboot_setup_warm_reset_vector() and smpboot_restore_warm_reset_vector()
invoke local_flush_tlb() for no obvious reason.

Digging in history revealed that the original code in the 2.1 era added
those because the code manipulated a swapper_pg_dir pagetable entry. The
pagetable manipulation was removed long ago in the 2.3 timeframe, but the
TLB flush invocations stayed around forever.

Remove them along with the pointless pr_debug()s which come from the same 2.1
change.
Reported-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linuxfoundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20171230211829.586548655@linutronix.deSigned-off-by: Ingo Molnar <mingo@kernel.org>

Pull SCSI fixes from James Bottomley:
 "Two simple fixes, both of which cause I/O hangs.

  The storvsc one is from the hyper-v which can hang under certain hot
  add/remove conditions and the other is generally, where removing a
  target and a device in close proximity can result in the release
  method being executed twice (and subsequent list and other corruption
  and an eventual panic)"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: storvsc: Fix scsi_cmd error assignments in storvsc_handle_error
  scsi: core: check for device state in __scsi_remove_target()

Fix a seg fault which happens when an input file provided to 'objtool
orc generate' doesn't have a '.shstrtab' section (for instance, object
files produced by clang don't have this section).
Signed-off-by: Simon Ser <contact@emersion.fr>
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>
Link: http://lkml.kernel.org/r/c0f2231683e9bed40fac1f13ce2c33b8389854bc.1514666459.git.jpoimboe@redhat.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

Fix a seg fault when no parameter is provided to 'objtool orc'.
Signed-off-by: Simon Ser <contact@emersion.fr>
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>
Link: http://lkml.kernel.org/r/9172803ec7ebb72535bcd0b7f966ae96d515968e.1514666459.git.jpoimboe@redhat.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

Pull HID fixes from Jiri Kosina:

 - two cosmetic fixes from Daniel Axtens and Hans de Goede

 - fix for I2C command mismatch fix for cp2112 driver from Eudean Sun

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid:
  HID: core: lower log level for unknown main item tags to warnings
  HID: holtekff: move MODULE_* parameters out of #ifdef block
  HID: cp2112: Fix I2C_BLOCK_DATA transactions

It appears that hardened gentoo enables "-fstack-check" by default for
gcc.

That doesn't work _at_all_ for the kernel, because the kernel stack
doesn't act like a user stack at all: it's much smaller, and it doesn't
auto-expand on use.  So the extra "probe one page below the stack" code
generated by -fstack-check just breaks the kernel in horrible ways,
causing infinite double faults etc.

[ I have to say, that the particular code gcc generates looks very
  stupid even for user space where it works, but that's a separate
  issue.  ]
Reported-and-tested-by: Alexander Tsoy <alexander@tsoy.me>
Reported-and-tested-by: Toralf Förster <toralf.foerster@gmx.de>
Cc: stable@kernel.org
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>