For a PUD hugepage entry, we need to propagate bits [32:22]
from virtual address to resolve at 4M granularity. However,
the current code was incorrectly propagating bits [29:19].
This bug can cause incorrect data to be returned for pages
backed with 16G hugepages.
Signed-off-by: Nitin Gupta <nitin.m.gupta@oracle.com>
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

Switch to using the new timer_setup() and from_timer()
in LDOM Virtual I/O handshake.

Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Allen Pais <allen.pais@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

atomic_t variables are currently used to implement reference
counters with the following properties:
 - counter is initialized to 1 using atomic_set()
 - a resource is freed upon counter reaching zero
 - once counter reaches zero, its further
   increments aren't allowed
 - counter schema uses basic atomic operations
   (set, inc, inc_not_zero, dec_and_test, etc.)

Such atomic variables should be converted to a newly provided
refcount_t type and API that prevents accidental counter overflows
and underflows. This is important since overflows and underflows
can lead to use-after-free situation and be exploitable.

The variable mdesc_handle.refcnt is used as pure reference counter.
Convert it to refcount_t and fix up the operations.
Suggested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: David Windsor <dwindsor@gmail.com>
Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Acked-by: Shannon Nelson <shannon.nelson@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly. Adds a static variable to hold timeout
value.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geliang Tang <geliangtang@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: sparclinux@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Vijay Kumar says:

====================
sparc64: Optimize fls and __fls

SPARC provides lzcnt instruction (with VIS3) which can be used to
optimize fls, __fls and fls64 functions. For the systems that supports
lzcnt instruction, we now do boot time patching to use sparc
optimized fls, __fls and fls64 functions.

v3->v4:
 -  Fixed a typo.
v2->v3:
 -  Using ENTRY(), ENDPROC() for assembler functions.
 -  Removed BITS_PER_LONG from __fls.
 -  Using generic fls64().
 -  Replaced lzcnt instruction with .word directive.
v1->v2:
 - Fixed delay slot issue.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

For T4 and above, patch fls and __fls functions
at the boot time to use lzcnt instruction.
Signed-off-by: Vijay Kumar <vijay.ac.kumar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Defined SPARC optimized __fls using lzcnt opcode.
Signed-off-by: Vijay Kumar <vijay.ac.kumar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Defined SPARC optimized fls using lzcnt opcode.
Signed-off-by: Vijay Kumar <vijay.ac.kumar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

__fls will now require a boot time patching on T4 and above.
Redefining it under arch/sparc/lib.
Signed-off-by: Vijay Kumar <vijay.ac.kumar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

fls will now require a boot time patching on T4 and above.
Redefining it under arch/sparc/lib.
Signed-off-by: Vijay Kumar <vijay.ac.kumar@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Following patch is based on work done by Nick Alcock on 64-bit vDSO for sparc
in Oracle linux. I have extended it to include support for 32-bit vDSO for sparc
on 64-bit kernel.

vDSO for sparc is based on the X86 implementation. This patch
provides vDSO support for both 64-bit and 32-bit programs on 64-bit kernel.
vDSO will be disabled on 32-bit linux kernel on sparc.

*) vclock_gettime.c contains all the vdso functions. Since data page is mapped
   before the vdso code page, the pointer to data page is got by subracting offset
   from an address in the vdso code page. The return address stored in
   %i7 is used for this purpose.
*) During compilation, both 32-bit and 64-bit vdso images are compiled and are
   converted into raw bytes by vdso2c program to be ready for mapping into the
   process. 32-bit images are compiled only if CONFIG_COMPAT is enabled. vdso2c
   generates two files vdso-image-64.c and vdso-image-32.c which contains the
   respective vDSO image in C structure.
*) During vdso initialization, required number of vdso pages are allocated and
   raw bytes are copied into the pages.
*) During every exec, these pages are mapped into the process through
   arch_setup_additional_pages and the location of mapping is passed on to the
   process through aux vector AT_SYSINFO_EHDR which is used by glibc.
*) A new update_vsyscall routine for sparc is added to keep the data page in
   vdso updated.
*) As vDSO cannot contain dynamically relocatable references, a new version of
   cpu_relax is added for the use of vDSO.

This change also requires a putback to glibc to use vDSO. For testing,
programs planning to try vDSO can be compiled against the generated
vdso(64/32).so in the source.

Testing:

========
[root@localhost ~]# cat vdso_test.c
int main() {
        struct timespec tv_start, tv_end;
        struct timeval tv_tmp;
	int i;
        int count = 1 * 1000 * 10000;
	long long diff;

        clock_gettime(0, &tv_start);
        for (i = 0; i < count; i++)
              gettimeofday(&tv_tmp, NULL);
        clock_gettime(0, &tv_end);
        diff = (long long)(tv_end.tv_sec -
		tv_start.tv_sec)*(1*1000*1000*1000);
        diff += (tv_end.tv_nsec - tv_start.tv_nsec);
	printf("Start sec: %d\n", tv_start.tv_sec);
	printf("End sec  : %d\n", tv_end.tv_sec);
        printf("%d cycles in %lld ns = %f ns/cycle\n", count, diff,
		(double)diff / (double)count);
        return 0;
}

[root@localhost ~]# cc vdso_test.c -o t32_without_fix -m32 -lrt
[root@localhost ~]# ./t32_without_fix
Start sec: 1502396130
End sec  : 1502396140
10000000 cycles in 9565148528 ns = 956.514853 ns/cycle
[root@localhost ~]# cc vdso_test.c -o t32_with_fix -m32 ./vdso32.so.dbg
[root@localhost ~]# ./t32_with_fix
Start sec: 1502396168
End sec  : 1502396169
10000000 cycles in 798141262 ns = 79.814126 ns/cycle
[root@localhost ~]# cc vdso_test.c -o t64_without_fix -m64 -lrt
[root@localhost ~]# ./t64_without_fix
Start sec: 1502396208
End sec  : 1502396218
10000000 cycles in 9846091800 ns = 984.609180 ns/cycle
[root@localhost ~]# cc vdso_test.c -o t64_with_fix -m64 ./vdso64.so.dbg
[root@localhost ~]# ./t64_with_fix
Start sec: 1502396257
End sec  : 1502396257
10000000 cycles in 380984048 ns = 38.098405 ns/cycle

V1 to V2 Changes:
=================
	Added hot patching code to switch the read stick instruction to read
tick instruction based on the hardware.

V2 to V3 Changes:
=================
	Merged latest changes from sparc-next and moved the initialization
of clocksource_tick.archdata.vclock_mode to time_init_early. Disabled
queued spinlock and rwlock configuration when simulating 32-bit config
to compile 32-bit VDSO.

V3 to V4 Changes:
=================
	Hardcoded the page size as 8192 in linker script for both 64-bit and
32-bit binaries. Removed unused variables in vdso2c.h. Added -mv8plus flag to
Makefile to prevent the generation of relocation entries for __lshrdi3 in 32-bit
vdso binary.
Signed-off-by: Nick Alcock <nick.alcock@oracle.com>
Signed-off-by: Nagarathnam Muthusamy <nagarathnam.muthusamy@oracle.com>
Reviewed-by: Shannon Nelson <shannon.nelson@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This fixes the build with i40e driver enabled.
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch move the define for D7S_MINOR to include/linux/miscdevice.h.
It's better that all minor number are in the same place.
Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc/kernel/time_64.c does not contain any miscdevice so the
inclusion of linux/miscdevice.h is unnecessary.
Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fix the following build errors.

In file included from arch/sparc/include/asm/mmu_context.h:4:0,
                 from include/linux/mmu_context.h:4,
		 from drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.h:29,
		 from drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.c:23:
arch/sparc/include/asm/mmu_context_64.h:22:37: error:
	unknown type name 'per_cpu_secondary_mm'

arch/sparc/include/asm/mmu_context_64.h: In function 'switch_mm':
arch/sparc/include/asm/mmu_context_64.h:79:2: error:
	implicit declaration of function 'smp_processor_id'

Fixes: 70539bd7 ("drm/amd: Update MEC HQD loading code for KFD")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull quota and isofs fixes from Jan Kara:
 "Two quota fixes (fallout of the quota locking changes) and an isofs
  build fix"

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  quota: Fix quota corruption with generic/232 test
  isofs: fix build regression
  quota: add missing lock into __dquot_transfer()

Merge tag 'linux-kselftest-4.14-rc3-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull kselftest fixes from Shuah Khan:
 "This update consists of:

   - fixes to several existing tests

   - a test for regression introduced by b9470c27 ("inet: kill
     smallest_size and smallest_port")

   - seccomp support for glibc 2.26 siginfo_t.h

   - fixes to kselftest framework and tests to run make O=dir use-case

   - fixes to silence unnecessary test output to de-clutter test results"

* tag 'linux-kselftest-4.14-rc3-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (28 commits)
  selftests: timers: set-timer-lat: Fix hang when testing unsupported alarms
  selftests: timers: set-timer-lat: fix hang when std out/err are redirected
  selftests/memfd: correct run_tests.sh permission
  selftests/seccomp: Support glibc 2.26 siginfo_t.h
  selftests: futex: Makefile: fix for loops in targets to run silently
  selftests: Makefile: fix for loops in targets to run silently
  selftests: mqueue: Use full path to run tests from Makefile
  selftests: futex: copy sub-dir test scripts for make O=dir run
  selftests: lib.mk: copy test scripts and test files for make O=dir run
  selftests: sync: kselftest and kselftest-clean fail for make O=dir case
  selftests: sync: use TEST_CUSTOM_PROGS instead of TEST_PROGS
  selftests: lib.mk: add TEST_CUSTOM_PROGS to allow custom test run/install
  selftests: watchdog: fix to use TEST_GEN_PROGS and remove clean
  selftests: lib.mk: fix test executable status check to use full path
  selftests: Makefile: clear LDFLAGS for make O=dir use-case
  selftests: lib.mk: kselftest and kselftest-clean fail for make O=dir case
  Makefile: kselftest and kselftest-clean fail for make O=dir case
  selftests/net: msg_zerocopy enable build with older kernel headers
  selftests: actually run the various net selftests
  selftest: add a reuseaddr test
  ...

Pull x86 fpu fixes and cleanups from Ingo Molnar:
 "This is _way_ more cleanups than fixes, but the bugs were subtle and
  hard to hit, and the primary reason for them existing was the
  unnecessary historical complexity of some of the x86/fpu interfaces.

  The first bunch of commits clean up and simplify the xstate user copy
  handling functions, in reaction to the collective head-scratching
  about the xstate user-copy handling code that leads up to the fix for
  this SkyLake xstate handling bug:

     0852b374: x86/fpu: Add FPU state copying quirk to handle XRSTOR failure on Intel Skylake CPUs

  The cleanups don't change any functionality, they just (hopefully)
  make it all clearer, more consistent, more debuggable and more robust.

  Note that most of the linecount increase comes from these commits,
  where we better split the user/kernel copy logic by having more
  variants, instead repeated fragile patterns of:

               if (kbuf) {
                       memcpy(kbuf + pos, data, copy);
               } else {
                       if (__copy_to_user(ubuf + pos, data, copy))
                               return -EFAULT;
               }

  The next bunch of commits simplify the FPU state-machine to get rid of
  old lazy-FPU idiosyncrasies - a defensive simplification to make all
  the code easier to review and fix. No change in functionality.

  Then there's a couple of additional debugging tweaks: static checker
  warning fix and move an FPU related warning to under WARN_ON_FPU(),
  followed by another bunch of commits that represent a finegrained
  split-up of the fixes from Eric Biggers to handle weird xstate bits
  properly.

  I did this finegrained split-up because some of these fixes also
  impact the ABI for weird xstate handling, for which we'd like to have
  good bisection results, should they cause any problems. (We also had
  one regression with the more monolithic fixes, so splitting it all up
  sounded prudent for robustness reasons as well.)

  About the whole series: the commits up to 03eaec81 have been in
  -next for months - but I've recently rebased them to remove a state
  machine clean-up commit that was objected to, and to make it more
  bisectable - so technically it's a new, rebased tree.

  Robustness history: this series had some regressions along the way,
  and all reported regressions have been fixed. All but one of the
  regressions manifested itself as easy to report warnings. The previous
  version of this latest series was also in linux-next, with one
  (warning-only) regression reported which is fixed in the latest
  version.

  Barring last minute brown paper bag bugs (and the commits are now
  older by a day which I'd hope helps paperbag reduction), I'm
  reasonably confident about its general robustness.

  Famous last words ..."

* 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (42 commits)
  x86/fpu: Use using_compacted_format() instead of open coded X86_FEATURE_XSAVES
  x86/fpu: Use validate_xstate_header() to validate the xstate_header in copy_user_to_xstate()
  x86/fpu: Eliminate the 'xfeatures' local variable in copy_user_to_xstate()
  x86/fpu: Copy the full header in copy_user_to_xstate()
  x86/fpu: Use validate_xstate_header() to validate the xstate_header in copy_kernel_to_xstate()
  x86/fpu: Eliminate the 'xfeatures' local variable in copy_kernel_to_xstate()
  x86/fpu: Copy the full state_header in copy_kernel_to_xstate()
  x86/fpu: Use validate_xstate_header() to validate the xstate_header in __fpu__restore_sig()
  x86/fpu: Use validate_xstate_header() to validate the xstate_header in xstateregs_set()
  x86/fpu: Introduce validate_xstate_header()
  x86/fpu: Rename fpu__activate_fpstate_read/write() to fpu__prepare_[read|write]()
  x86/fpu: Rename fpu__activate_curr() to fpu__initialize()
  x86/fpu: Simplify and speed up fpu__copy()
  x86/fpu: Fix stale comments about lazy FPU logic
  x86/fpu: Rename fpu::fpstate_active to fpu::initialized
  x86/fpu: Remove fpu__current_fpstate_write_begin/end()
  x86/fpu: Fix fpu__activate_fpstate_read() and update comments
  x86/fpu: Reinitialize FPU registers if restoring FPU state fails
  x86/fpu: Don't let userspace set bogus xcomp_bv
  x86/fpu: Turn WARN_ON() in context switch into WARN_ON_FPU()
  ...

Eric has reported that since commit d2faa415 "quota: Do not acquire
dqio_sem for dquot overwrites in v2 format" test generic/232
occasionally fails due to quota information being incorrect. Indeed that
commit was too eager to remove dqio_sem completely from the path that
just overwrites quota structure with updated information. Although that
is innocent on its own, another process that inserts new quota structure
to the same block can perform read-modify-write cycle of that block thus
effectively discarding quota information update if they race in a wrong
way.

Fix the problem by acquiring dqio_sem for reading for overwrites of
quota structure. Note that it *is* possible to completely avoid taking
dqio_sem in the overwrite path however that will require modifying path
inserting / deleting quota structures to avoid RMW cycles of the full
block and for now it is not clear whether it is worth the hassle.

Fixes: d2faa415Reported-and-tested-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

Pull MMC fixes from Ulf Hansson:

  - sdhci-pci: Fix voltage switch for some Intel host controllers

  - tmio: remove broken and noisy debug macro

* tag 'mmc-v4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
  mmc: sdhci-pci: Fix voltage switch for some Intel host controllers
  mmc: tmio: remove broken and noisy debug macro

In generic_file_llseek_size, return -ENXIO for negative offsets as well
as offsets beyond EOF.  This affects filesystems which don't implement
SEEK_HOLE / SEEK_DATA internally, possibly because they don't support
holes.

Fixes xfstest generic/448.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: Ingo Molnar <mingo@kernel.org>

This is the canonical method to use.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-11-mingo@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

Tighten the checks in copy_user_to_xstate().
Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-10-mingo@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

We now have this field in hdr.xfeatures.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-9-mingo@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

This is in preparation to verify the full xstate header as supplied by user-space.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-8-mingo@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

Tighten the checks in copy_kernel_to_xstate().
Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-7-mingo@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

We have this information in the xstate_header.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-6-mingo@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

This is in preparation to verify the full xstate header as supplied by user-space.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-5-mingo@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

Tighten the checks in __fpu__restore_sig() and update comments.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-4-mingo@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

Tighten the checks in xstateregs_set().
Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-3-mingo@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

Move validation of user-supplied xstate_header into a helper function,
in preparation of calling it from both the ptrace and sigreturn syscall
paths.

The new function also considers it to be an error if *any* reserved bits
are set, whereas before we were just clearing most of them silently.

This should reduce the chance of bugs that fail to correctly validate
user-supplied XSAVE areas.  It also will expose any broken userspace
programs that set the other reserved bits; this is desirable because
such programs will lose compatibility with future CPUs and kernels if
those bits are ever used for anything.  (There shouldn't be any such
programs, and in fact in the case where the compacted format is in use
we were already validating xfeatures.  But you never know...)
Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-2-mingo@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

As per the new nomenclature we don't 'activate' the FPU state
anymore, we initialize it. So drop the _activate_fpstate name
from these functions, which were a bit of a mouthful anyway,
and name them:

	fpu__prepare_read()
	fpu__prepare_write()

Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Rename this function to better express that it's all about
initializing the FPU state of a task which goes hand in hand
with the fpu::initialized field.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-33-mingo@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

fpu__copy() has a preempt_disable()/enable() pair, which it had to do to
be able to atomically unlazy the current task when doing an FNSAVE.

But we don't unlazy tasks anymore, we always do direct saves/restores of
FPU context.

So remove both the unnecessary critical section, and update the comments.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-32-mingo@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

We don't do any lazy restore anymore, what we have are two pieces of optimization:

 - no-FPU tasks that don't save/restore the FPU context (kernel threads are such)

 - cached FPU registers maintained via the fpu->last_cpu field. This means that
   if an FPU task context switches to a non-FPU task then we can maintain the
   FPU registers as an in-FPU copies (cache), and skip the restoration of them
   once we switch back to the original FPU-using task.

Update all the comments that still referred to old 'lazy' and 'unlazy' concepts.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-31-mingo@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

The x86 FPU code used to have a complex state machine where both the FPU
registers and the FPU state context could be 'active' (or inactive)
independently of each other - which enabled features like lazy FPU restore.

Much of this complexity is gone in the current code: now we basically can
have FPU-less tasks (kernel threads) that don't use (and save/restore) FPU
state at all, plus full FPU users that save/restore directly with no laziness
whatsoever.

But the fpu::fpstate_active still carries bits of the old complexity - meanwhile
this flag has become a simple flag that shows whether the FPU context saving
area in the thread struct is initialized and used, or not.

Rename it to fpu::initialized to express this simplicity in the name as well.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-30-mingo@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

These functions are not used anymore, so remove them.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-29-mingo@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

fpu__activate_fpstate_read() can be called for the current task
when coredumping - or for stopped tasks when ptrace-ing.

Implement this properly in the code and update the comments.

This also fixes an incorrect (but harmless) warning introduced by
one of the earlier patches.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-28-mingo@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

Pull compat fix from Al Viro:
 "I really wish gcc warned about conversions from pointer to function
  into void *..."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fix a typo in put_compat_shm_info()