Commit Graph

30345 Commits

Author SHA1 Message Date
Thomas Gleixner 1ccea77e2a treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 13
Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not see http www gnu org licenses

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details [based]
  [from] [clk] [highbank] [c] you should have received a copy of the
  gnu general public license along with this program if not see http
  www gnu org licenses

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 355 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Jilayne Lovejoy <opensource@jilayne.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190519154041.837383322@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 11:28:45 +02:00
Thomas Gleixner d6cd1e9b9f treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 9
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not you can access it online at http www gnu
  org licenses gpl 2 0 html

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Jilayne Lovejoy <opensource@jilayne.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190519154041.430943677@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 11:28:40 +02:00
Thomas Gleixner ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Thomas Gleixner 457c899653 treewide: Add SPDX license identifier for missed files
Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have EXPORT_.*_SYMBOL_GPL inside which was used in the
   initial scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:45 +02:00
Linus Torvalds cb6f8739fb Merge branch 'akpm' (patches from Andrew)
Merge yet more updates from Andrew Morton:
 "A few final bits:

   - large changes to vmalloc, yielding large performance benefits

   - tweak the console-flush-on-panic code

   - a few fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  panic: add an option to replay all the printk message in buffer
  initramfs: don't free a non-existent initrd
  fs/writeback.c: use rcu_barrier() to wait for inflight wb switches going into workqueue when umount
  mm/compaction.c: correct zone boundary handling when isolating pages from a pageblock
  mm/vmap: add DEBUG_AUGMENT_LOWEST_MATCH_CHECK macro
  mm/vmap: add DEBUG_AUGMENT_PROPAGATE_CHECK macro
  mm/vmalloc.c: keep track of free blocks for vmap allocation
2019-05-19 12:15:32 -07:00
Linus Torvalds d9351ea14d Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull IRQ chip updates from Ingo Molnar:
 "A late irqchips update:

   - New TI INTR/INTA set of drivers

   - Rewrite of the stm32mp1-exti driver as a platform driver

   - Update the IOMMU MSI mapping API to be RT friendly

   - A number of cleanups and other low impact fixes"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits)
  iommu/dma-iommu: Remove iommu_dma_map_msi_msg()
  irqchip/gic-v3-mbi: Don't map the MSI page in mbi_compose_m{b, s}i_msg()
  irqchip/ls-scfg-msi: Don't map the MSI page in ls_scfg_msi_compose_msg()
  irqchip/gic-v3-its: Don't map the MSI page in its_irq_compose_msi_msg()
  irqchip/gicv2m: Don't map the MSI page in gicv2m_compose_msi_msg()
  iommu/dma-iommu: Split iommu_dma_map_msi_msg() in two parts
  genirq/msi: Add a new field in msi_desc to store an IOMMU cookie
  arm64: arch_k3: Enable interrupt controller drivers
  irqchip/ti-sci-inta: Add msi domain support
  soc: ti: Add MSI domain bus support for Interrupt Aggregator
  irqchip/ti-sci-inta: Add support for Interrupt Aggregator driver
  dt-bindings: irqchip: Introduce TISCI Interrupt Aggregator bindings
  irqchip/ti-sci-intr: Add support for Interrupt Router driver
  dt-bindings: irqchip: Introduce TISCI Interrupt router bindings
  gpio: thunderx: Use the default parent apis for {request,release}_resources
  genirq: Introduce irq_chip_{request,release}_resource_parent() apis
  firmware: ti_sci: Add helper apis to manage resources
  firmware: ti_sci: Add RM mapping table for am654
  firmware: ti_sci: Add support for IRQ management
  firmware: ti_sci: Add support for RM core ops
  ...
2019-05-19 10:58:45 -07:00
Feng Tang de6da1e8bc panic: add an option to replay all the printk message in buffer
Currently on panic, kernel will lower the loglevel and print out pending
printk msg only with console_flush_on_panic().

Add an option for users to configure the "panic_print" to replay all
dmesg in buffer, some of which they may have never seen due to the
loglevel setting, which will help panic debugging .

[feng.tang@intel.com: keep the original console_flush_on_panic() inside panic()]
  Link: http://lkml.kernel.org/r/1556199137-14163-1-git-send-email-feng.tang@intel.com
[feng.tang@intel.com: use logbuf lock to protect the console log index]
  Link: http://lkml.kernel.org/r/1556269868-22654-1-git-send-email-feng.tang@intel.com
Link: http://lkml.kernel.org/r/1556095872-36838-1-git-send-email-feng.tang@intel.com
Signed-off-by: Feng Tang <feng.tang@intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: Aaro Koskinen <aaro.koskinen@nokia.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Borislav Petkov <bp@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-18 15:52:26 -07:00
Linus Torvalds 5f3ab27b9e Merge branch 'for-5.2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fix from Tejun Heo:
 "The cgroup2 freezer pulled in this cycle broke strace. This pull
  request includes a workaround for the problem.

  It's not a complete fix in that it may cause spurious frozen state
  flip-flops which is fairly minor. Will push a full fix once it's
  ready"

* 'for-5.2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  signal: unconditionally leave the frozen state in ptrace_stop()
2019-05-16 19:01:23 -07:00
Linus Torvalds b2c3dda6f8 Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull time fixes from Ingo Molnar:
 "A TIA adjtimex interface extension, and a POSIX compliance ABI fix for
  timespec64 users"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  ntp: Allow TAI-UTC offset to be set to zero
  y2038: Make CONFIG_64BIT_TIME unconditional
2019-05-16 11:00:20 -07:00
Linus Torvalds f57d7715d7 Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fix from Ingo Molnar:
 "A single rwsem fix"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/rwsem: Prevent decrement of reader count before increment
2019-05-16 10:54:19 -07:00
Roman Gushchin 05b2892637 signal: unconditionally leave the frozen state in ptrace_stop()
Alex Xu reported a regression in strace, caused by the introduction of
the cgroup v2 freezer. The regression can be reproduced by stracing
the following simple program:

  #include <unistd.h>

  int main() {
      write(1, "a", 1);
      return 0;
  }

An attempt to run strace ./a.out leads to the infinite loop:
  [ pre-main omitted ]
  write(1, "a", 1)                        = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
  write(1, "a", 1)                        = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
  write(1, "a", 1)                        = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
  write(1, "a", 1)                        = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
  write(1, "a", 1)                        = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
  write(1, "a", 1)                        = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
  [ repeats forever ]

The problem occurs because the traced task leaves ptrace_stop()
(and the signal handling loop) with the frozen bit set. So let's
call cgroup_leave_frozen(true) unconditionally after sleeping
in ptrace_stop().

With this patch applied, strace works as expected:
  [ pre-main omitted ]
  write(1, "a", 1)                        = 1
  exit_group(0)                           = ?
  +++ exited with 0 +++

Reported-by: Alex Xu <alex_y_xu@yahoo.ca>
Fixes: 76f969e894 ("cgroup: cgroup v2 freezer")
Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
2019-05-16 10:43:58 -07:00
Linus Torvalds d2d8b14604 The major changes in this tracing update includes:
- Removing of non-DYNAMIC_FTRACE from 32bit x86
 
  - Removing of mcount support from x86
 
  - Emulating a call from int3 on x86_64, fixes live kernel patching
 
  - Consolidated Tracing Error logs file
 
 Minor updates:
 
  - Removal of klp_check_compiler_support()
 
  - kdb ftrace dumping output changes
 
  - Accessing and creating ftrace instances from inside the kernel
 
  - Clean up of #define if macro
 
  - Introduction of TRACE_EVENT_NOP() to disable trace events based on config
    options
 
 And other minor fixes and clean ups
 -----BEGIN PGP SIGNATURE-----
 
 iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXNxMZxQccm9zdGVkdEBn
 b29kbWlzLm9yZwAKCRAp5XQQmuv6qq4PAP44kP6VbwL8CHyI2A3xuJ6Hwxd+2Z2r
 ip66RtzyJ+2iCgEA2QCuWUlEt2bLpF9a8IQ4N9tWenSeW2i7gunPb+tioQw=
 =RVQo
 -----END PGP SIGNATURE-----

Merge tag 'trace-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing updates from Steven Rostedt:
 "The major changes in this tracing update includes:

   - Removal of non-DYNAMIC_FTRACE from 32bit x86

   - Removal of mcount support from x86

   - Emulating a call from int3 on x86_64, fixes live kernel patching

   - Consolidated Tracing Error logs file

  Minor updates:

   - Removal of klp_check_compiler_support()

   - kdb ftrace dumping output changes

   - Accessing and creating ftrace instances from inside the kernel

   - Clean up of #define if macro

   - Introduction of TRACE_EVENT_NOP() to disable trace events based on
     config options

  And other minor fixes and clean ups"

* tag 'trace-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (44 commits)
  x86: Hide the int3_emulate_call/jmp functions from UML
  livepatch: Remove klp_check_compiler_support()
  ftrace/x86: Remove mcount support
  ftrace/x86_32: Remove support for non DYNAMIC_FTRACE
  tracing: Simplify "if" macro code
  tracing: Fix documentation about disabling options using trace_options
  tracing: Replace kzalloc with kcalloc
  tracing: Fix partial reading of trace event's id file
  tracing: Allow RCU to run between postponed startup tests
  tracing: Fix white space issues in parse_pred() function
  tracing: Eliminate const char[] auto variables
  ring-buffer: Fix mispelling of Calculate
  tracing: probeevent: Fix to make the type of $comm string
  tracing: probeevent: Do not accumulate on ret variable
  tracing: uprobes: Re-enable $comm support for uprobe events
  ftrace/x86_64: Emulate call function while updating in breakpoint handler
  x86_64: Allow breakpoints to emulate call instructions
  x86_64: Add gap to int3 to allow for call emulation
  tracing: kdb: Allow ftdump to skip all but the last few entries
  tracing: Add trace_total_entries() / trace_total_entries_cpu()
  ...
2019-05-15 16:05:47 -07:00
Stephen Rothwell 89963adcdb kernel/compat.c: mark expected switch fall-throughs
In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

This patch aims to suppress 3 missing-break-in-switch false positives
on some architectures.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: Gustavo A. R. Silva <gustavo@embeddedor.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Jann Horn <jannh@google.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-15 08:16:14 -07:00
Linus Torvalds 1064d85773 Merge branch 'akpm' (patches from Andrew)
Merge more updates from Andrew Morton:

 - a couple of hotfixes

 - almost all of the rest of MM

 - lib/ updates

 - binfmt_elf updates

 - autofs updates

 - quite a lot of misc fixes and updates
    - reiserfs, fatfs
    - signals
    - exec
    - cpumask
    - rapidio
    - sysctl
    - pids
    - eventfd
    - gcov
    - panic
    - pps

 - gdb script updates

 - ipc updates

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (126 commits)
  mm: memcontrol: fix NUMA round-robin reclaim at intermediate level
  mm: memcontrol: fix recursive statistics correctness & scalabilty
  mm: memcontrol: move stat/event counting functions out-of-line
  mm: memcontrol: make cgroup stats and events query API explicitly local
  drivers/virt/fsl_hypervisor.c: prevent integer overflow in ioctl
  drivers/virt/fsl_hypervisor.c: dereferencing error pointers in ioctl
  mm, memcg: rename ambiguously named memory.stat counters and functions
  arch: remove <asm/sizes.h> and <asm-generic/sizes.h>
  treewide: replace #include <asm/sizes.h> with #include <linux/sizes.h>
  fs/block_dev.c: Remove duplicate header
  fs/cachefiles/namei.c: remove duplicate header
  include/linux/sched/signal.h: replace `tsk' with `task'
  fs/coda/psdev.c: remove duplicate header
  ipc: do cyclic id allocation for the ipc object.
  ipc: conserve sequence numbers in ipcmni_extend mode
  ipc: allow boot time extension of IPCMNI from 32k to 16M
  ipc/mqueue: optimize msg_get()
  ipc/mqueue: remove redundant wq task assignment
  ipc: prevent lockup on alloc_msg and free_msg
  scripts/gdb: print cached rate in lx-clk-summary
  ...
2019-05-14 20:08:51 -07:00
Aaro Koskinen b287a25a71 panic/reboot: allow specifying reboot_mode for panic only
Allow specifying reboot_mode for panic only.  This is needed on systems
where ramoops is used to store panic logs, and user wants to use warm
reset to preserve those, while still having cold reset on normal
reboots.

Link: http://lkml.kernel.org/r/20190322004735.27702-1-aaro.koskinen@iki.fi
Signed-off-by: Aaro Koskinen <aaro.koskinen@nokia.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:51 -07:00
Feng Tang c39ea0b9dd panic: avoid the extra noise dmesg
When kernel panic happens, it will first print the panic call stack,
then the ending msg like:

[   35.743249] ---[ end Kernel panic - not syncing: Fatal exception
[   35.749975] ------------[ cut here ]------------

The above message are very useful for debugging.

But if system is configured to not reboot on panic, say the
"panic_timeout" parameter equals 0, it will likely print out many noisy
message like WARN() call stack for each and every CPU except the panic
one, messages like below:

	WARNING: CPU: 1 PID: 280 at kernel/sched/core.c:1198 set_task_cpu+0x183/0x190
	Call Trace:
	<IRQ>
	try_to_wake_up
	default_wake_function
	autoremove_wake_function
	__wake_up_common
	__wake_up_common_lock
	__wake_up
	wake_up_klogd_work_func
	irq_work_run_list
	irq_work_tick
	update_process_times
	tick_sched_timer
	__hrtimer_run_queues
	hrtimer_interrupt
	smp_apic_timer_interrupt
	apic_timer_interrupt

For people working in console mode, the screen will first show the panic
call stack, but immediately overridden by these noisy extra messages,
which makes debugging much more difficult, as the original context gets
lost on screen.

Also these noisy messages will confuse some users, as I have seen many bug
reporters posted the noisy message into bugzilla, instead of the real
panic call stack and context.

Adding a flag "suppress_printk" which gets set in panic() to avoid those
noisy messages, without changing current kernel behavior that both panic
blinking and sysrq magic key can work as is, suggested by Petr Mladek.

To verify this, make sure kernel is not configured to reboot on panic and
in console
 # echo c > /proc/sysrq-trigger
to see if console only prints out the panic call stack.

Link: http://lkml.kernel.org/r/1551430186-24169-1-git-send-email-feng.tang@intel.com
Signed-off-by: Feng Tang <feng.tang@intel.com>
Suggested-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kees Cook <keescook@chromium.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Sasha Levin <sashal@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:51 -07:00
Greg Hackmann e178a5beb3 gcov: clang support
LLVM uses profiling data that's deliberately similar to GCC, but has a
very different way of exporting that data.  LLVM calls llvm_gcov_init()
once per module, and provides a couple of callbacks that we can use to
ask for more data.

We care about the "writeout" callback, which in turn calls back into
compiler-rt/this module to dump all the gathered coverage data to disk:

   llvm_gcda_start_file()
     llvm_gcda_emit_function()
     llvm_gcda_emit_arcs()
     llvm_gcda_emit_function()
     llvm_gcda_emit_arcs()
     [... repeats for each function ...]
   llvm_gcda_summary_info()
   llvm_gcda_end_file()

This design is much more stateless and unstructured than gcc's, and is
intended to run at process exit.  This forces us to keep some local
state about which module we're dealing with at the moment.  On the other
hand, it also means we don't depend as much on how LLVM represents
profiling data internally.

See LLVM's lib/Transforms/Instrumentation/GCOVProfiling.cpp for more
details on how this works, particularly GCOVProfiler::emitProfileArcs(),
GCOVProfiler::insertCounterWriteout(), and GCOVProfiler::insertFlush().

[akpm@linux-foundation.org: coding-style fixes]
Link: http://lkml.kernel.org/r/20190417225328.208129-1-trong@android.com
Signed-off-by: Greg Hackmann <ghackmann@android.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Tri Vo <trong@android.com>
Co-developed-by: Nick Desaulniers <ndesaulniers@google.com>
Co-developed-by: Tri Vo <trong@android.com>
Tested-by: Trilok Soni <tsoni@quicinc.com>
Tested-by: Prasad Sodagudi <psodagud@quicinc.com>
Tested-by: Tri Vo <trong@android.com>
Tested-by: Daniel Mentz <danielmentz@google.com>
Tested-by: Petri Gynther <pgynther@google.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:51 -07:00
Greg Hackmann 826eba0d77 gcov: clang: move common GCC code into gcc_base.c
Patch series "gcov: add Clang support", v4.

This patch (of 3):

base.c contains a few callbacks specific to GCC's gcov implementation.
Move these into their own module in preparation for Clang support.

Link: http://lkml.kernel.org/r/20190318025411.98014-2-trong@android.com
Signed-off-by: Greg Hackmann <ghackmann@android.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Tri Vo <trong@android.com>
Tested-by: Trilok Soni <tsoni@quicinc.com>
Tested-by: Prasad Sodagudi <psodagud@quicinc.com>
Tested-by: Tri Vo <trong@android.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Cc: Daniel Mentz <danielmentz@google.com>
Cc: Petri Gynther <pgynther@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:51 -07:00
Timmy Li 1fd402df45 kernel/pid.c: remove unneeded hash header file
Hash functions are not needed since idr is used now.  Let's remove hash
header file for cleanup.

Link: http://lkml.kernel.org/r/20190430053319.95913-1-scuttimmy@gmail.com
Signed-off-by: Timmy Li <scuttimmy@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: KJ Tsanaktsidis <ktsanaktsidis@zendesk.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:51 -07:00
Eric Sandeen 3116ad38f5 kernel/sysctl.c: fix proc_do_large_bitmap for large input buffers
Today, proc_do_large_bitmap() truncates a large write input buffer to
PAGE_SIZE - 1, which may result in misparsed numbers at the (truncated)
end of the buffer.  Further, it fails to notify the caller that the
buffer was truncated, so it doesn't get called iteratively to finish the
entire input buffer.

Tell the caller if there's more work to do by adding the skipped amount
back to left/*lenp before returning.

To fix the misparsing, reset the position if we have completely consumed
a truncated buffer (or if just one char is left, which may be a "-" in a
range), and ask the caller to come back for more.

Link: http://lkml.kernel.org/r/20190320222831.8243-7-mcgrof@kernel.org
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:51 -07:00
Christian Brauner e260ad01f0 sysctl: return -EINVAL if val violates minmax
Currently when userspace gives us a values that overflow e.g.  file-max
and other callers of __do_proc_doulongvec_minmax() we simply ignore the
new value and leave the current value untouched.

This can be problematic as it gives the illusion that the limit has
indeed be bumped when in fact it failed.  This commit makes sure to
return EINVAL when an overflow is detected.  Please note that this is a
userspace facing change.

Link: http://lkml.kernel.org/r/20190210203943.8227-4-christian@brauner.io
Signed-off-by: Christian Brauner <christian@brauner.io>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Waiman Long <longman@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:51 -07:00
Andy Shevchenko 475dae3854 kernel/sysctl.c: switch to bitmap_zalloc()
Switch to bitmap_zalloc() to show clearly what we are allocating.
Besides that it returns pointer of bitmap type instead of opaque void *.

Link: http://lkml.kernel.org/r/20190304094037.57756-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:51 -07:00
Mathieu Malaterre b028fb6128 kernel/signal.c: annotate implicit fall through
There is a plan to build the kernel with -Wimplicit-fallthrough and this
place in the code produced a warning (W=1).

This commit remove the following warning:

  kernel/signal.c:795:13: warning: this statement may fall through [-Wimplicit-fallthrough=]

Link: http://lkml.kernel.org/r/20190114203505.17875-1-malat@debian.org
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Acked-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:50 -07:00
Rasmus Villemoes 6c4e121fda kernel/user.c: clean up some leftover code
The out_unlock label is misleading; no unlocking happens after it, so
just return NULL directly.

Also, nothing between the kmem_cache_zalloc() that creates new and the
two key_put() can initialize new->uid_keyring or new->session_keyring,
so those calls are no-ops.

Link: http://lkml.kernel.org/r/20190424200404.9114-1-linux@rasmusvillemoes.dk
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:49 -07:00
Lin Feng e02c9b0d65 kernel/latencytop.c: rename clear_all_latency_tracing to clear_tsk_latency_tracing
The name clear_all_latency_tracing is misleading, in fact which only
clear per task's latency_record[], and we do have another function named
clear_global_latency_tracing which clear the global latency_record[]
buffer.

Link: http://lkml.kernel.org/r/20190226114602.16902-1-linf@wangsu.com
Signed-off-by: Lin Feng <linf@wangsu.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Fabian Frederick <fabf@skynet.be>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:49 -07:00
Lin Feng 0cc75888da kernel/latencytop.c: remove unnecessary checks for latencytop_enabled
1. In latencytop source codes, we only have such calling chain:

account_scheduler_latency(struct task_struct *task, int usecs, int inter)
{
        if (unlikely(latencytop_enabled)) /* the outtermost check */
                __account_scheduler_latency(task, usecs, inter);
}
__account_scheduler_latency
    account_global_scheduler_latency
        if (!latencytop_enabled)

So, the inner check for latencytop_enabled is not necessary at all.

2. In clear_all_latency_tracing and now is called
   clear_tsk_latency_tracing the check for latencytop_enabled is redundant
   and buggy to some extent.

   We have no reason to refuse clearing the /proc/$pid/latency if
   latencytop_enabled is set to 0, considering that if we use latencytop
   manually by echo 0 > /proc/sys/kernel/latencytop, then we want to clear
   /proc/$pid/latency and failed.

   Also we don't have such check in brother function
   clear_global_latency_tracing.

Notes: These changes are only visible to users who set
   CONFIG_LATENCYTOP and won't change user tool latencytop's behavior.

Link: http://lkml.kernel.org/r/20190226114602.16902-2-linf@wangsu.com
Signed-off-by: Lin Feng <linf@wangsu.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Fabian Frederick <fabf@skynet.be>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:49 -07:00
Vasily Averin 831246570d kernel/notifier.c: double register detection
By design notifiers can be registerd once only, 2nd register attempt
called by mistake silently corrupts notifiers list.

A few years ago I investigated described problem, the host was power
cycled because of notifier list corruption.  I've prepared this patch
and applied it to the OpenVZ kernel and sent this patch but nobody
commented on it.  Later it helped us to detect a similar problem in the
OpenVz kernel.

Mistakes with notifier registration can happen for example during
subsystem initialization from different namespaces, or because of a lost
unregister in the roll-back path on initialization failures.

The proposed check cannot prevent the described problem, however it
allows us to detect its reason quickly without coredump analysis.

Link: http://lkml.kernel.org/r/04127e71-4782-9bbb-fe5a-7c01e93a99b0@virtuozzo.com
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:49 -07:00
Dan Schatzberg df5ba5be74 kernel/sched/psi.c: expose pressure metrics on root cgroup
Pressure metrics are already recorded and exposed in procfs for the
entire system, but any tool which monitors cgroup pressure has to
special case the root cgroup to read from procfs.  This patch exposes
the already recorded pressure metrics on the root cgroup.

Link: http://lkml.kernel.org/r/20190510174938.3361741-1-dschatzberg@fb.com
Signed-off-by: Dan Schatzberg <dschatzberg@fb.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:48 -07:00
Suren Baghdasaryan 0e94682b73 psi: introduce psi monitor
Psi monitor aims to provide a low-latency short-term pressure detection
mechanism configurable by users.  It allows users to monitor psi metrics
growth and trigger events whenever a metric raises above user-defined
threshold within user-defined time window.

Time window and threshold are both expressed in usecs.  Multiple psi
resources with different thresholds and window sizes can be monitored
concurrently.

Psi monitors activate when system enters stall state for the monitored
psi metric and deactivate upon exit from the stall state.  While system
is in the stall state psi signal growth is monitored at a rate of 10
times per tracking window.  Min window size is 500ms, therefore the min
monitoring interval is 50ms.  Max window size is 10s with monitoring
interval of 1s.

When activated psi monitor stays active for at least the duration of one
tracking window to avoid repeated activations/deactivations when psi
signal is bouncing.

Notifications to the users are rate-limited to one per tracking window.

Link: http://lkml.kernel.org/r/20190319235619.260832-8-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:48 -07:00
Suren Baghdasaryan 8af0c18af1 include/: refactor headers to allow kthread.h inclusion in psi_types.h
kthread.h can't be included in psi_types.h because it creates a circular
inclusion with kthread.h eventually including psi_types.h and
complaining on kthread structures not being defined because they are
defined further in the kthread.h.  Resolve this by removing psi_types.h
inclusion from the headers included from kthread.h.

Link: http://lkml.kernel.org/r/20190319235619.260832-7-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:48 -07:00
Suren Baghdasaryan 333f3017c5 psi: track changed states
Introduce changed_states parameter into collect_percpu_times to track
the states changed since the last update.

This will be needed to detect whether polled states activated in the
monitor patch.

Link: http://lkml.kernel.org/r/20190319235619.260832-6-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:48 -07:00
Suren Baghdasaryan 7fc70a3999 psi: split update_stats into parts
Split update_stats into collect_percpu_times and update_averages for
collect_percpu_times to be reused later inside psi monitor.

Link: http://lkml.kernel.org/r/20190319235619.260832-5-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:47 -07:00
Suren Baghdasaryan bcc78db641 psi: rename psi fields in preparation for psi trigger addition
Rename psi_group structure member fields used for calculating psi totals
and averages for clear distinction between them and for trigger-related
fields that will be added by "psi: introduce psi monitor".

[surenb@google.com: v6]
  Link: http://lkml.kernel.org/r/20190319235619.260832-4-surenb@google.com
Link: http://lkml.kernel.org/r/20190124211518.244221-5-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:47 -07:00
Suren Baghdasaryan 9289c5e6a7 psi: make psi_enable static
psi_enable is not used outside of psi.c, make it static.

Link: http://lkml.kernel.org/r/20190319235619.260832-3-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:47 -07:00
Suren Baghdasaryan 33b2d6302a psi: introduce state_mask to represent stalled psi states
Patch series "psi: pressure stall monitors", v6.

This is a respin of:
  https://lwn.net/ml/linux-kernel/20190308184311.144521-1-surenb%40google.com/

Android is adopting psi to detect and remedy memory pressure that
results in stuttering and decreased responsiveness on mobile devices.

Psi gives us the stall information, but because we're dealing with
latencies in the millisecond range, periodically reading the pressure
files to detect stalls in a timely fashion is not feasible.  Psi also
doesn't aggregate its averages at a high-enough frequency right now.

This patch series extends the psi interface such that users can
configure sensitive latency thresholds and use poll() and friends to be
notified when these are breached.

As high-frequency aggregation is costly, it implements an aggregation
method that is optimized for fast, short-interval averaging, and makes
the aggregation frequency adaptive, such that high-frequency updates
only happen while monitored stall events are actively occurring.

With these patches applied, Android can monitor for, and ward off,
mounting memory shortages before they cause problems for the user.  For
example, using memory stall monitors in userspace low memory killer
daemon (lmkd) we can detect mounting pressure and kill less important
processes before device becomes visibly sluggish.  In our memory stress
testing psi memory monitors produce roughly 10x less false positives
compared to vmpressure signals.  Having ability to specify multiple
triggers for the same psi metric allows other parts of Android framework
to monitor memory state of the device and act accordingly.

The new interface is straight-forward.  The user opens one of the
pressure files for writing and writes a trigger description into the
file descriptor that defines the stall state - some or full, and the
maximum stall time over a given window of time.  E.g.:

        /* Signal when stall time exceeds 100ms of a 1s window */
        char trigger[] = "full 100000 1000000"
        fd = open("/proc/pressure/memory")
        write(fd, trigger, sizeof(trigger))
        while (poll() >= 0) {
                ...
        };
        close(fd);

When the monitored stall state is entered, psi adapts its aggregation
frequency according to what the configured time window requires in order
to emit event signals in a timely fashion.  Once the stalling subsides,
aggregation reverts back to normal.

The trigger is associated with the open file descriptor.  To stop
monitoring, the user only needs to close the file descriptor and the
trigger is discarded.

Patches 1-6 prepare the psi code for polling support.  Patch 7
implements the adaptive polling logic, the pressure growth detection
optimized for short intervals, and hooks up write() and poll() on the
pressure files.

The patches were developed in collaboration with Johannes Weiner.

This patch (of 7):

The psi monitoring patches will need to determine the same states as
record_times().  To avoid calculating them twice, maintain a state mask
that can be consulted cheaply.  Do this in a separate patch to keep the
churn in the main feature patch at a minimum.

This adds 4-byte state_mask member into psi_group_cpu struct which
results in its first cacheline-aligned part becoming 52 bytes long.  Add
explicit values to enumeration element counters that affect
psi_group_cpu struct size.

Link: http://lkml.kernel.org/r/20190124211518.244221-4-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:47 -07:00
Andrea Arcangeli 987717e5e0 mm: change mm_update_next_owner() to update mm->owner with WRITE_ONCE
The RCU reader uses rcu_dereference() inside rcu_read_lock critical
sections, so the writer shall use WRITE_ONCE.  Just a cleanup, we still
rely on gcc to emit atomic writes in other places.

Link: http://lkml.kernel.org/r/20190325225636.11635-3-aarcange@redhat.com
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:47 -07:00
Andrea Arcangeli c3f3ce049f userfaultfd: use RCU to free the task struct when fork fails
The task structure is freed while get_mem_cgroup_from_mm() holds
rcu_read_lock() and dereferences mm->owner.

  get_mem_cgroup_from_mm()                failing fork()
  ----                                    ---
  task = mm->owner
                                          mm->owner = NULL;
                                          free(task)
  if (task) *task; /* use after free */

The fix consists in freeing the task with RCU also in the fork failure
case, exactly like it always happens for the regular exit(2) path.  That
is enough to make the rcu_read_lock hold in get_mem_cgroup_from_mm()
(left side above) effective to avoid a use after free when dereferencing
the task structure.

An alternate possible fix would be to defer the delivery of the
userfaultfd contexts to the monitor until after fork() is guaranteed to
succeed.  Such a change would require more changes because it would
create a strict ordering dependency where the uffd methods would need to
be called beyond the last potentially failing branch in order to be
safe.  This solution as opposed only adds the dependency to common code
to set mm->owner to NULL and to free the task struct that was pointed by
mm->owner with RCU, if fork ends up failing.  The userfaultfd methods
can still be called anywhere during the fork runtime and the monitor
will keep discarding orphaned "mm" coming from failed forks in userland.

This race condition couldn't trigger if CONFIG_MEMCG was set =n at build
time.

[aarcange@redhat.com: improve changelog, reduce #ifdefs per Michal]
  Link: http://lkml.kernel.org/r/20190429035752.4508-1-aarcange@redhat.com
Link: http://lkml.kernel.org/r/20190325225636.11635-2-aarcange@redhat.com
Fixes: 893e26e61d ("userfaultfd: non-cooperative: Add fork() event")
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Tested-by: zhong jiang <zhongjiang@huawei.com>
Reported-by: syzbot+cbb52e396df3e565ab02@syzkaller.appspotmail.com
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: zhong jiang <zhongjiang@huawei.com>
Cc: syzbot+cbb52e396df3e565ab02@syzkaller.appspotmail.com
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:47 -07:00
Andrew Morton acb2ec3dd0 kernel/Makefile: don't assume that kernel/gen_ikh_data.sh is executable
If the user downloads and applies patch-5.1.gz using patch(1), the x bit
on kernel/gen_ikh_data.sh is not set.

  /bin/sh: 1: ./kernel/gen_ikh_data.sh: Permission denied

Fix this by using CONFIG_SHELL.

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:47 -07:00
Linus Torvalds ca4b40629f kgdb patches for 5.2-rc1
Mostly clean ups but there are also a couple of out-of-bounds accesses
 (including a potential write to the byte before a static buffer).
 
 The main changes are:
 
  * Fixes those out-of-bounds access (empty string to configure
    test module could write the byte before a buffer, high cpu counts
    could read outside of per-cpu structures).
 
  * Improvements to string handling problems picked up by new compiler
    warnings and other static checks. Most are fixing benign issues that
    can't be tickled without code changes but still reduce the wtf factor
    a little.
 
  * Tidy up the terminal output.
 
 Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCAAdFiEELzVBU1D3lWq6cKzwfOMlXTn3iKEFAlza6CEACgkQfOMlXTn3
 iKHkwA/8CmCq7UA3ZZsItHYn48Xa4YzxySErhpocsqa7U7tPh7f7ETv6NkfmjxEQ
 MGmQflKw/yU3avR6eHUfJcd4AO3+x0Vi5wR9fhevAVu3sfnjTjTjP0F2tDjWe+Y/
 TJob4/gSssmDp1+DtFvOQdOmGVz9C7xMQ2wZFjQcpAwesLLbwu+KPZDcBPpyRnl1
 zSOIUtTxHH6ay2PX57CNAWEmE4SFoUha7712GTHVHe3rykrC+CLYNeCRzUuyTSAz
 OaPTNzd/OFz+uLcsvTPothpc3wUfM4MUkuCkAVKpuMcB2D+/7WqqszUfHYWJ27bH
 oeYqRyeQaRa6COFkxZ4XZQRMBOYzzidVboTDjlTj391qq5L32tje75TtfHgCJ/p7
 vlg0QdbrHOFaDF9aXcmqLr7kNRi83NxNPhg4XHA75MRHFBGvRkMd3jmuZdShFKc7
 Yegr+pR0FJwivZz8+UcRPAdI5gdmSWLdpeB2GhtZqDk3975Qjvsy90ieG7GQnjR8
 /ewoYsFQ5/qXwyZzJ+kHxAmTMWpGYx8Kge77j5UMljPsuSuHU56vUt4ovzSiSzuX
 dTAxLRmrYi6Dlri76EHEoE+1mx301ymK4MXMz8WnNVQhnPnkCcEXx7P3neCB/wuX
 w1O2VvMQ8b4si1/M71QFcAgQjMcJz7z8wGwhfnnqFPgZmVT5n/8=
 =SsRX
 -----END PGP SIGNATURE-----

Merge tag 'kgdb-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux

Pull kgdb updates from Daniel Thompson:
 "Mostly cleanups but there are also a couple of fixes for out-of-bounds
  accesses (including a potential write to the byte before a static
  buffer).

  The main changes are:

   - Fixes to those out-of-bounds access (empty string to configure test
     module could write the byte before a buffer, high cpu counts could
     read outside of per-cpu structures).

   - Improvements to string handling problems picked up by new compiler
     warnings and other static checks. Most are fixing benign issues
     that can't be tickled without code changes but still reduce the wtf
     factor a little.

   - Tidy up the terminal output"

* tag 'kgdb-5.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux:
  kdb: Fix bound check compiler warning
  kdb: do a sanity check on the cpu in kdb_per_cpu()
  kdb: Get rid of broken attempt to print CCVERSION in kdb summary
  misc: kgdbts: fix out-of-bounds access in function param_set_kgdbts_var
  kdb: kdb_support: replace strcpy() by strscpy()
  gdbstub: Replace strcpy() by strscpy()
  gdbstub: mark expected switch fall-throughs
2019-05-14 13:14:10 -07:00
Linus Torvalds 280664f558 Modules updates for v5.2
Summary of modules changes for the 5.2 merge window:
 
 - Use a separate table to store symbol types instead of
   hijacking fields in struct Elf_Sym
 
 - Trivial code cleanups
 
 Signed-off-by: Jessica Yu <jeyu@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQIcBAABCgAGBQJc2W9gAAoJEMBFfjjOO8FyAqkP+wbCB42LJ8kD2H+pbxpsf7vU
 T1+5fZ3rfyLqHDc9Pzt1K6SBR04aLq8OXW3nOIQ5kmirSstiznokAExQBjeMegVJ
 14Q5IxOSQ44rBPg5ggCA6s9qNyw2fqgwKWQKXLW+VmYAHiBfIBV0mO576KWIEgE1
 vOCQPqW0ccfmjEssumEYMSePg01LATjso3PMcdJm6yI74xSGd8n872y36BleAP8M
 232L8B4fuZEuHJ1QaBnXdapKibyMX3k3WbfK9U2RzSWaGjmuBXwihCB+ZA6HCiRX
 MVwXQwh63UGCZLYkXnGMwPNgX5TTZRiPT4oIhB0tGIXkEFX/DlA+NGfuinEAYuKS
 M0zhjgjSOKYEhNy1GtirbHjNCC4ULF0OZvD/dB8InQON0/t5Duq3sOHSp9+rWMg7
 yuHy3NJGHHd65nGd7u7vXmdZXct/NVDdahKhqRA8i+HOxUBdF9vvMMnSASXufWFt
 j5GSFA5/IZKpYofho/jvJK2rmQQVkVpD9zWCZcv8BNT124W4cZ5swOOSVYOnSAJb
 Wvy1oknjF/HrKIft3UIFR0FU8uIueP0mtnna2B9SBVfZm7rM+/3+a1D/UOHaLtuO
 ++b1sIOpyApevRZcXpTnH63ZaO2tRC7KnDzaBT8FTZimEyV5KdD6Ec2MKJdi8Nkb
 Pr099LJ2i/i8rQbkjM1i
 =NO31
 -----END PGP SIGNATURE-----

Merge tag 'modules-for-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux

Pull modules updates from Jessica Yu:

 - Use a separate table to store symbol types instead of hijacking
   fields in struct Elf_Sym

 - Trivial code cleanups

* tag 'modules-for-v5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  module: add stubs for within_module functions
  kallsyms: store type information in its own array
  vmlinux.lds.h: drop unused __vermagic
2019-05-14 10:55:54 -07:00
Linus Torvalds 318222a35b Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:

 - a few misc things and hotfixes

 - ocfs2

 - almost all of MM

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (139 commits)
  kernel/memremap.c: remove the unused device_private_entry_fault() export
  mm: delete find_get_entries_tag
  mm/huge_memory.c: make __thp_get_unmapped_area static
  mm/mprotect.c: fix compilation warning because of unused 'mm' variable
  mm/page-writeback: introduce tracepoint for wait_on_page_writeback()
  mm/vmscan: simplify trace_reclaim_flags and trace_shrink_flags
  mm/Kconfig: update "Memory Model" help text
  mm/vmscan.c: don't disable irq again when count pgrefill for memcg
  mm: memblock: make keeping memblock memory opt-in rather than opt-out
  hugetlbfs: always use address space in inode for resv_map pointer
  mm/z3fold.c: support page migration
  mm/z3fold.c: add structure for buddy handles
  mm/z3fold.c: improve compression by extending search
  mm/z3fold.c: introduce helper functions
  mm/page_alloc.c: remove unnecessary parameter in rmqueue_pcplist
  mm/hmm: add ARCH_HAS_HMM_MIRROR ARCH_HAS_HMM_DEVICE Kconfig
  mm/vmscan.c: simplify shrink_inactive_list()
  fs/sync.c: sync_file_range(2) may use WB_SYNC_ALL writeback
  xen/privcmd-buf.c: convert to use vm_map_pages_zero()
  xen/gntdev.c: convert to use vm_map_pages()
  ...
2019-05-14 10:10:55 -07:00
Christoph Hellwig 640be2d1ff kernel/memremap.c: remove the unused device_private_entry_fault() export
This export has been entirely unused since it was added more than 1 1/2
years ago.

Link: http://lkml.kernel.org/r/20190429115535.12793-1-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 09:47:51 -07:00
Mike Rapoport 350e88bad4 mm: memblock: make keeping memblock memory opt-in rather than opt-out
Most architectures do not need the memblock memory after the page
allocator is initialized, but only few enable ARCH_DISCARD_MEMBLOCK in the
arch Kconfig.

Replacing ARCH_DISCARD_MEMBLOCK with ARCH_KEEP_MEMBLOCK and inverting the
logic makes it clear which architectures actually use memblock after
system initialization and skips the necessity to add ARCH_DISCARD_MEMBLOCK
to the architectures that are still missing that option.

Link: http://lkml.kernel.org/r/1556102150-32517-1-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 09:47:50 -07:00
Michal Hocko 940519f0c8 mm, memory_hotplug: provide a more generic restrictions for memory hotplug
arch_add_memory, __add_pages take a want_memblock which controls whether
the newly added memory should get the sysfs memblock user API (e.g.
ZONE_DEVICE users do not want/need this interface).  Some callers even
want to control where do we allocate the memmap from by configuring
altmap.

Add a more generic hotplug context for arch_add_memory and __add_pages.
struct mhp_restrictions contains flags which contains additional features
to be enabled by the memory hotplug (MHP_MEMBLOCK_API currently) and
altmap for alternative memmap allocator.

This patch shouldn't introduce any functional change.

[akpm@linux-foundation.org: build fix]
Link: http://lkml.kernel.org/r/20190408082633.2864-3-osalvador@suse.de
Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Oscar Salvador <osalvador@suse.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 09:47:49 -07:00
Jérôme Glisse 7269f99993 mm/mmu_notifier: use correct mmu_notifier events for each invalidation
This updates each existing invalidation to use the correct mmu notifier
event that represent what is happening to the CPU page table.  See the
patch which introduced the events to see the rational behind this.

Link: http://lkml.kernel.org/r/20190326164747.24405-7-jglisse@redhat.com
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Ross Zwisler <zwisler@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Christian Koenig <christian.koenig@amd.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 09:47:49 -07:00
Jérôme Glisse 6f4f13e8d9 mm/mmu_notifier: contextual information for event triggering invalidation
CPU page table update can happens for many reasons, not only as a result
of a syscall (munmap(), mprotect(), mremap(), madvise(), ...) but also as
a result of kernel activities (memory compression, reclaim, migration,
...).

Users of mmu notifier API track changes to the CPU page table and take
specific action for them.  While current API only provide range of virtual
address affected by the change, not why the changes is happening.

This patchset do the initial mechanical convertion of all the places that
calls mmu_notifier_range_init to also provide the default MMU_NOTIFY_UNMAP
event as well as the vma if it is know (most invalidation happens against
a given vma).  Passing down the vma allows the users of mmu notifier to
inspect the new vma page protection.

The MMU_NOTIFY_UNMAP is always the safe default as users of mmu notifier
should assume that every for the range is going away when that event
happens.  A latter patch do convert mm call path to use a more appropriate
events for each call.

This is done as 2 patches so that no call site is forgotten especialy
as it uses this following coccinelle patch:

%<----------------------------------------------------------------------
@@
identifier I1, I2, I3, I4;
@@
static inline void mmu_notifier_range_init(struct mmu_notifier_range *I1,
+enum mmu_notifier_event event,
+unsigned flags,
+struct vm_area_struct *vma,
struct mm_struct *I2, unsigned long I3, unsigned long I4) { ... }

@@
@@
-#define mmu_notifier_range_init(range, mm, start, end)
+#define mmu_notifier_range_init(range, event, flags, vma, mm, start, end)

@@
expression E1, E3, E4;
identifier I1;
@@
<...
mmu_notifier_range_init(E1,
+MMU_NOTIFY_UNMAP, 0, I1,
I1->vm_mm, E3, E4)
...>

@@
expression E1, E2, E3, E4;
identifier FN, VMA;
@@
FN(..., struct vm_area_struct *VMA, ...) {
<...
mmu_notifier_range_init(E1,
+MMU_NOTIFY_UNMAP, 0, VMA,
E2, E3, E4)
...> }

@@
expression E1, E2, E3, E4;
identifier FN, VMA;
@@
FN(...) {
struct vm_area_struct *VMA;
<...
mmu_notifier_range_init(E1,
+MMU_NOTIFY_UNMAP, 0, VMA,
E2, E3, E4)
...> }

@@
expression E1, E2, E3, E4;
identifier FN;
@@
FN(...) {
<...
mmu_notifier_range_init(E1,
+MMU_NOTIFY_UNMAP, 0, NULL,
E2, E3, E4)
...> }
---------------------------------------------------------------------->%

Applied with:
spatch --all-includes --sp-file mmu-notifier.spatch fs/proc/task_mmu.c --in-place
spatch --sp-file mmu-notifier.spatch --dir kernel/events/ --in-place
spatch --sp-file mmu-notifier.spatch --dir mm --in-place

Link: http://lkml.kernel.org/r/20190326164747.24405-6-jglisse@redhat.com
Signed-off-by: Jérôme Glisse <jglisse@redhat.com>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Ross Zwisler <zwisler@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Christian Koenig <christian.koenig@amd.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 09:47:49 -07:00
Ira Weiny 73b0140bf0 mm/gup: change GUP fast to use flags rather than a write 'bool'
To facilitate additional options to get_user_pages_fast() change the
singular write parameter to be gup_flags.

This patch does not change any functionality.  New functionality will
follow in subsequent patches.

Some of the get_user_pages_fast() call sites were unchanged because they
already passed FOLL_WRITE or 0 for the write parameter.

NOTE: It was suggested to change the ordering of the get_user_pages_fast()
arguments to ensure that callers were converted.  This breaks the current
GUP call site convention of having the returned pages be the final
parameter.  So the suggestion was rejected.

Link: http://lkml.kernel.org/r/20190328084422.29911-4-ira.weiny@intel.com
Link: http://lkml.kernel.org/r/20190317183438.2057-4-ira.weiny@intel.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Mike Marshall <hubcap@omnibond.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 09:47:46 -07:00
Peter Xu cefdca0a86 userfaultfd/sysctl: add vm.unprivileged_userfaultfd
Userfaultfd can be misued to make it easier to exploit existing
use-after-free (and similar) bugs that might otherwise only make a
short window or race condition available.  By using userfaultfd to
stall a kernel thread, a malicious program can keep some state that it
wrote, stable for an extended period, which it can then access using an
existing exploit.  While it doesn't cause the exploit itself, and while
it's not the only thing that can stall a kernel thread when accessing a
memory location, it's one of the few that never needs privilege.

We can add a flag, allowing userfaultfd to be restricted, so that in
general it won't be useable by arbitrary user programs, but in
environments that require userfaultfd it can be turned back on.

Add a global sysctl knob "vm.unprivileged_userfaultfd" to control
whether userfaultfd is allowed by unprivileged users.  When this is
set to zero, only privileged users (root user, or users with the
CAP_SYS_PTRACE capability) will be able to use the userfaultfd
syscalls.

Andrea said:

: The only difference between the bpf sysctl and the userfaultfd sysctl
: this way is that the bpf sysctl adds the CAP_SYS_ADMIN capability
: requirement, while userfaultfd adds the CAP_SYS_PTRACE requirement,
: because the userfaultfd monitor is more likely to need CAP_SYS_PTRACE
: already if it's doing other kind of tracking on processes runtime, in
: addition of userfaultfd.  In other words both syscalls works only for
: root, when the two sysctl are opt-in set to 1.

[dgilbert@redhat.com: changelog additions]
[akpm@linux-foundation.org: documentation tweak, per Mike]
Link: http://lkml.kernel.org/r/20190319030722.12441-2-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Suggested-by: Andrea Arcangeli <aarcange@redhat.com>
Suggested-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Maxime Coquelin <maxime.coquelin@redhat.com>
Cc: Maya Gokhale <gokhale2@llnl.gov>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Martin Cracauer <cracauer@cons.org>
Cc: Denis Plotnikov <dplotnikov@virtuozzo.com>
Cc: Marty McFadden <mcfadden8@llnl.gov>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 09:47:45 -07:00
Cyrill Gorcunov a9e73998f9 kernel/sys.c: prctl: fix false positive in validate_prctl_map()
While validating new map we require the @start_data to be strictly less
than @end_data, which is fine for regular applications (this is why this
nit didn't trigger for that long).  These members are set from executable
loaders such as elf handers, still it is pretty valid to have a loadable
data section with zero size in file, in such case the start_data is equal
to end_data once kernel loader finishes.

As a result when we're trying to restore such programs the procedure fails
and the kernel returns -EINVAL.  From the image dump of a program:

 | "mm_start_code": "0x400000",
 | "mm_end_code": "0x8f5fb4",
 | "mm_start_data": "0xf1bfb0",
 | "mm_end_data": "0xf1bfb0",

Thus we need to change validate_prctl_map from strictly less to less or
equal operator use.

Link: http://lkml.kernel.org/r/20190408143554.GY1421@uranus.lan
Fixes: f606b77f1a ("prctl: PR_SET_MM -- introduce PR_SET_MM_MAP operation")
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Andrey Vagin <avagin@gmail.com>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 09:47:44 -07:00
Wenlin Kang ca976bfb31 kdb: Fix bound check compiler warning
The strncpy() function may leave the destination string buffer
unterminated, better use strscpy() instead.

This fixes the following warning with gcc 8.2:

kernel/debug/kdb/kdb_io.c: In function 'kdb_getstr':
kernel/debug/kdb/kdb_io.c:449:3: warning: 'strncpy' specified bound 256 equals destination size [-Wstringop-truncation]
   strncpy(kdb_prompt_str, prompt, CMD_BUFLEN);
   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Wenlin Kang <wenlin.kang@windriver.com>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
2019-05-14 13:44:24 +01:00