The x86 smpboot trampoline expects initial_page_table to have the
GDT mapped.  If the GDT ends up in a virtually mapped per-cpu page,
then it won't be in the page tables at all until perc-pu areas are
set up.  The result will be a triple fault the first time that the
CPU attempts to access the GDT after LGDT loads the perc-pu GDT.

This appears to be an old bug, but somehow the GDT fixmap rework
is triggering it.  This seems to have something to do with the
memory layout.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/a553264a5972c6a86f9b5caac237470a0c74a720.1490218061.git.luto@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

__pa() on a per-cpu pointer is invalid.  This bug appears to go *waaay*
back, and I guess it's just never been triggered.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/5ba1d3ffca85e1a5b3ac99265ebe55df4cf0dbe4.1490218061.git.luto@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

__pa() cannot be used on percpu pointers because they may be
virtually mapped.  Use per_cpu_ptr_to_phys() instead.

This fixes a boot crash on a some 32-bit configurations.  I assume
this is related to which allocation strategy is chosen by the percpu
core.
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 69218e47 x86: ("Remap GDT tables in the fixmap section")
Link: http://lkml.kernel.org/r/22e0069c29fba31998f193201e359eebfdac4960.1490218061.git.luto@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

i386 glibc is buggy and calls the sigaction syscall incorrectly.

This is asymptomatic for normal programs, but it blows up on
programs that do evil things with segmentation.  The ldt_gdt
self-test is an example of such an evil program.

This doesn't appear to be a regression -- I think I just got lucky
with the uninitialized memory that glibc threw at the kernel when I
wrote the test.

This hackish fix manually issues sigaction(2) syscalls to undo the
damage.  Without the fix, ldt_gdt_32 segfaults; with the fix, it
passes for me.

See: https://sourceware.org/bugzilla/show_bug.cgi?id=21269Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Garnier <thgarnie@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/aaab0f9f93c9af25396f01232608c163a760a668.1490218061.git.luto@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>

Instead of including fixmap.h twice in pgtable_32.h and pgtable_64.h,
include it only once, in the common asm/pgtable.h header.
Signed-off-by: Thomas Garnier <thgarnie@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Cc: kasan-dev@googlegroups.com
Cc: kernel-hardening@lists.openwall.com
Cc: linux-mm@kvack.org
Cc: richard.weiyang@gmail.com
Cc: zijun_hu <zijun_hu@htc.com>
Link: http://lkml.kernel.org/r/20170321071725.GA15782@gmail.com
[ Generated this patch from two other patches and wrote changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>

For mysterious historical reasons, struct user_desc doesn't indicate
whether segments are accessed.  set_thread_area() has always programmed
segments as non-accessed, so the first write will set the accessed bit.
This will fault if the GDT is read-only.

Fix it by making TLS segments start out accessed.

If this ends up breaking something, we could, in principle, leave TLS
segments non-accessed and fix them up when we get the page fault.  I'd be
surprised, though -- AFAIK all the nasty legacy segmented programs (DOSEMU,
Wine, things that run on DOSEMU and Wine, etc.) do their nasty segmented
things using the LDT and not the GDT.  I assume this is mainly because old
OSes (Linux and otherwise) didn't historically provide APIs to do nasty
things in the GDT.

Fixes: 45fc8757 ("x86: Make the GDT remapping read-only on 64-bit")
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Thomas Garnier <thgarnie@google.com>
Link: http://lkml.kernel.org/r/62b7748542df0164af7e0a5231283b9b13858c45.1489900519.git.luto@kernel.orgSigned-off-by: Thomas Gleixner <tglx@linutronix.de>

This patch provides all required callbacks required by the generic
get_user_pages_fast() code and switches x86 over - and removes
the platform specific implementation.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Aneesh Kumar K . V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dann Frazier <dann.frazier@canonical.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170316213906.89528-1-kirill.shutemov@linux.intel.com
[ Minor readability edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>

This is a preparation patch for the transition of x86 to the generic GUP_fast()
implementation.

On x86, get_user_pages_fast() does a couple of sanity checks to see if we can
call __get_user_pages_fast() for the range.

This kind of wrapping protection should be useful for the generic code too.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Aneesh Kumar K . V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dann Frazier <dann.frazier@canonical.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170316152655.37789-7-kirill.shutemov@linux.intel.com
[ Small readability edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>

This is a preparation patch for the transition of x86 to the generic GUP_fast()
implementation.

Prepare generic GUP_fast() to handle dev_pagemap(). At the moment, it's
only implemented on x86. On non-x86, the new code will be compiled out.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Aneesh Kumar K . V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dann Frazier <dann.frazier@canonical.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170316152655.37789-6-kirill.shutemov@linux.intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

This is a preparation patch for the transition of x86 to the generic GUP_fast()
implementation.

Unlike generic GUP_fast(), the x86 version makes all pages it touches
referenced. It seems required for GRU and EPT.

See the following commit:

  8ee53820 ("thp: mmu_notifier_test_young")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Aneesh Kumar K . V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dann Frazier <dann.frazier@canonical.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170316152655.37789-5-kirill.shutemov@linux.intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

This is a preparation patch for the transition of x86 to the generic GUP_fast()
implementation.

On x86 PAE, page table entry is larger than sizeof(long) and we would
need to provide a helper that can read the entry atomically.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Aneesh Kumar K . V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dann Frazier <dann.frazier@canonical.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170316152655.37789-4-kirill.shutemov@linux.intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

This is a preparation patch for the transition of x86 to the generic GUP_fast()
implementation.

On x86, we would need to do additional permission checks to determine if
access is allowed.

Let's abstract it out into separate helpers.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Aneesh Kumar K . V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dann Frazier <dann.frazier@canonical.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170316152655.37789-3-kirill.shutemov@linux.intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

The only arch that defines it to something meaningful is x86.
But x86 doesn't use the generic GUP_fast() implementation -- the
only place where the callback is called.

Let's drop it.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Aneesh Kumar K . V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dann Frazier <dann.frazier@canonical.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Steve Capper <steve.capper@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170316152655.37789-2-kirill.shutemov@linux.intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

This patch removes fixmap header usage on non-x86 code that was
introduced by the adaptable MODULE_END change.
Signed-off-by: Thomas Garnier <thgarnie@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/20170317175034.4701-1-thgarnie@google.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

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

Pull xfs fix from Darrick Wong:
 "Here's a single fix for -rc3 to improve input validation on inline
  directory data to prevent buffer overruns due to corrupt metadata"

* tag 'xfs-4.11-fixes-2' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: verify inline directory data forks

Pull arm64 fixes/cleanups from Catalin Marinas:
 "In Will's absence I'm sending the arm64 fixes he queued for 4.11-rc3:

   - fix arm64 kernel boot warning when DEBUG_VIRTUAL and KASAN are
     enabled

   - enable KEYS_COMPAT for keyctl compat support

   - use cpus_have_const_cap() for system_uses_ttbr0_pan() (slight
     performance improvement)

   - update kerneldoc for cpu_suspend() rename

   - remove the arm64-specific kprobe_exceptions_notify (weak generic
     variant defined)"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: kernel: Update kerneldoc for cpu_suspend() rename
  arm64: use const cap for system_uses_ttbr0_pan()
  arm64: support keyctl() system call in 32-bit mode
  arm64: kasan: avoid bad virt_to_pfn()
  arm64: kprobes: remove kprobe_exceptions_notify

Pull MD fixes from Shaohua Li:

 - fix a parity calculation bug of raid5 cache by Song

 - fix a potential deadlock issue by me

 - fix two endian issues by Jason

 - fix a disk limitation issue by Neil

 - other small fixes and cleanup

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
  md/raid1: fix a trivial typo in comments
  md/r5cache: fix set_syndrome_sources() for data in cache
  md: fix incorrect use of lexx_to_cpu in does_sb_need_changing
  md: fix super_offset endianness in super_1_rdev_size_change
  md/raid1/10: fix potential deadlock
  md: don't impose the MD_SB_DISKS limit on arrays without metadata.
  md: move funcs from pers->resize to update_size
  md-cluster: remove useless memset from gather_all_resync_info
  md-cluster: free md_cluster_info if node leave cluster
  md: delete dead code
  md/raid10: submit bio directly to replacement disk

This patch makes the GDT remapped pages read-only, to prevent accidental
(or intentional) corruption of this key data structure.

This change is done only on 64-bit, because 32-bit needs it to be writable
for TSS switches.

The native_load_tr_desc function was adapted to correctly handle a
read-only GDT. The LTR instruction always writes to the GDT TSS entry.
This generates a page fault if the GDT is read-only. This change checks
if the current GDT is a remap and swap GDTs as needed. This function was
tested by booting multiple machines and checking hibernation works
properly.

KVM SVM and VMX were adapted to use the writeable GDT. On VMX, the
per-cpu variable was removed for functions to fetch the original GDT.
Instead of reloading the previous GDT, VMX will reload the fixmap GDT as
expected. For testing, VMs were started and restored on multiple
configurations.
Signed-off-by: Thomas Garnier <thgarnie@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Luis R . Rodriguez <mcgrof@kernel.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: kasan-dev@googlegroups.com
Cc: kernel-hardening@lists.openwall.com
Cc: kvm@vger.kernel.org
Cc: lguest@lists.ozlabs.org
Cc: linux-doc@vger.kernel.org
Cc: linux-efi@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: linux-pm@vger.kernel.org
Cc: xen-devel@lists.xenproject.org
Cc: zijun_hu <zijun_hu@htc.com>
Link: http://lkml.kernel.org/r/20170314170508.100882-3-thgarnie@google.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

Each processor holds a GDT in its per-cpu structure. The sgdt
instruction gives the base address of the current GDT. This address can
be used to bypass KASLR memory randomization. With another bug, an
attacker could target other per-cpu structures or deduce the base of
the main memory section (PAGE_OFFSET).

This patch relocates the GDT table for each processor inside the
fixmap section. The space is reserved based on number of supported
processors.

For consistency, the remapping is done by default on 32 and 64-bit.

Each processor switches to its remapped GDT at the end of
initialization. For hibernation, the main processor returns with the
original GDT and switches back to the remapping at completion.

This patch was tested on both architectures. Hibernation and KVM were
both tested specially for their usage of the GDT.

Thanks to Boris Ostrovsky <boris.ostrovsky@oracle.com> for testing and
recommending changes for Xen support.
Signed-off-by: Thomas Garnier <thgarnie@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Luis R . Rodriguez <mcgrof@kernel.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: kasan-dev@googlegroups.com
Cc: kernel-hardening@lists.openwall.com
Cc: kvm@vger.kernel.org
Cc: lguest@lists.ozlabs.org
Cc: linux-doc@vger.kernel.org
Cc: linux-efi@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: linux-pm@vger.kernel.org
Cc: xen-devel@lists.xenproject.org
Cc: zijun_hu <zijun_hu@htc.com>
Link: http://lkml.kernel.org/r/20170314170508.100882-2-thgarnie@google.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

This patch aligns MODULES_END to the beginning of the fixmap section.
It optimizes the space available for both sections. The address is
pre-computed based on the number of pages required by the fixmap
section.

It will allow GDT remapping in the fixmap section. The current
MODULES_END static address does not provide enough space for the kernel
to support a large number of processors.
Signed-off-by: Thomas Garnier <thgarnie@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lorenzo Stoakes <lstoakes@gmail.com>
Cc: Luis R . Rodriguez <mcgrof@kernel.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: kasan-dev@googlegroups.com
Cc: kernel-hardening@lists.openwall.com
Cc: kvm@vger.kernel.org
Cc: lguest@lists.ozlabs.org
Cc: linux-doc@vger.kernel.org
Cc: linux-efi@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: linux-pm@vger.kernel.org
Cc: xen-devel@lists.xenproject.org
Cc: zijun_hu <zijun_hu@htc.com>
Link: http://lkml.kernel.org/r/20170314170508.100882-1-thgarnie@google.com
[ Small build fix. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Pull block fixes from Jens Axboe:
 "Four small fixes for this cycle:

   - followup fix from Neil for a fix that went in before -rc2, ensuring
     that we always see the full per-task bio_list.

   - fix for blk-mq-sched from me that ensures that we retain similar
     direct-to-issue behavior on running the queue.

   - fix from Sagi fixing a potential NULL pointer dereference in blk-mq
     on spurious CPU unplug.

   - a memory leak fix in writeback from Tahsin, fixing a case where
     device removal of a mounted device can leak a struct
     wb_writeback_work"

* 'for-linus' of git://git.kernel.dk/linux-block:
  blk-mq-sched: don't run the queue async from blk_mq_try_issue_directly()
  writeback: fix memory leak in wb_queue_work()
  blk-mq: Fix tagset reinit in the presence of cpu hot-unplug
  blk: Ensure users for current->bio_list can see the full list.

Pull SCSI fixes from James Bottomley:
 "This is a rather large set of fixes. The bulk are for lpfc correcting
  a lot of issues in the new NVME driver code which just went in in the
  merge window.

  The others are:

   - fix a hang in the vmware paravirt driver caused by incorrect
     handling of the new MSI vector allocation

   - long standing bug in storvsc, which recent block changes turned
     from being a harmless annoyance into a hang

   - yet more fallout (in mpt3sas) from the changes to device blocking

  The remainder are small fixes and updates"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (34 commits)
  scsi: lpfc: Add shutdown method for kexec
  scsi: storvsc: Workaround for virtual DVD SCSI version
  scsi: lpfc: revise version number to 11.2.0.10
  scsi: lpfc: code cleanups in NVME initiator discovery
  scsi: lpfc: code cleanups in NVME initiator base
  scsi: lpfc: correct rdp diag portnames
  scsi: lpfc: remove dead sli3 nvme code
  scsi: lpfc: correct double print
  scsi: lpfc: Rename LPFC_MAX_EQ_DELAY to LPFC_MAX_EQ_DELAY_EQID_CNT
  scsi: lpfc: Rework lpfc Kconfig for NVME options
  scsi: lpfc: add transport eh_timed_out reference
  scsi: lpfc: Fix eh_deadline setting for sli3 adapters.
  scsi: lpfc: add NVME exchange aborts
  scsi: lpfc: Fix nvme allocation bug on failed nvme_fc_register_localport
  scsi: lpfc: Fix IO submission if WQ is full
  scsi: lpfc: Fix NVME CMD IU byte swapped word 1 problem
  scsi: lpfc: Fix RCTL value on NVME LS request and response
  scsi: lpfc: Fix crash during Hardware error recovery on SLI3 adapters
  scsi: lpfc: fix missing spin_unlock on sql_list_lock
  scsi: lpfc: don't dereference dma_buf->iocbq before null check
  ...

Pull gfs2 fix from Bob Peterson:
 "This is an emergency patch for 4.11-rc3

  The GFS2 developers uncovered a really nasty problem that can lead to
  random corruption and kernel panic, much like the last one. Andreas
  Gruenbacher wrote a simple one-line patch to fix the problem."

* tag 'gfs2-4.11-rc3.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: Avoid alignment hole in struct lm_lockname

Pull crypto fixes from Herbert Xu:

 - self-test failure of crc32c on powerpc

 - regressions of ecb(aes) when used with xts/lrw in s5p-sss

 - a number of bugs in the omap RNG driver

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: s5p-sss - Fix spinlock recursion on LRW(AES)
  hwrng: omap - Do not access INTMASK_REG on EIP76
  hwrng: omap - use devm_clk_get() instead of of_clk_get()
  hwrng: omap - write registers after enabling the clock
  crypto: s5p-sss - Fix completing crypto request in IRQ handler
  crypto: powerpc - Fix initialisation of crc32c context

Commit 88ffbf3e switches to using rhashtables for glocks, hashing over
the entire struct lm_lockname instead of its individual fields.  On some
architectures, struct lm_lockname contains a hole of uninitialized
memory due to alignment rules, which now leads to incorrect hash values.
Get rid of that hole.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
CC: <stable@vger.kernel.org> #v4.3+

When we're reading or writing the data fork of an inline directory,
check the contents to make sure we're not overflowing buffers or eating
garbage data.  xfs/348 corrupts an inline symlink into an inline
directory, triggering a buffer overflow bug.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
---
v2: add more checks consistent with _dir2_sf_check and make the verifier
usable from anywhere.

Pull networking fixes from David Miller:

 1) Ensure that mtu is at least IPV6_MIN_MTU in ipv6 VTI tunnel driver,
    from Steffen Klassert.

 2) Fix crashes when user tries to get_next_key on an LPM bpf map, from
    Alexei Starovoitov.

 3) Fix detection of VLAN fitlering feature for bnx2x VF devices, from
    Michal Schmidt.

 4) We can get a divide by zero when TCP socket are morphed into
    listening state, fix from Eric Dumazet.

 5) Fix socket refcounting bugs in skb_complete_wifi_ack() and
    skb_complete_tx_timestamp(). From Eric Dumazet.

 6) Use after free in dccp_feat_activate_values(), also from Eric
    Dumazet.

 7) Like bonding team needs to use ETH_MAX_MTU as netdev->max_mtu, from
    Jarod Wilson.

 8) Fix use after free in vrf_xmit(), from David Ahern.

 9) Don't do UDP Fragmentation Offload on IPComp ipsec packets, from
    Alexey Kodanev.

10) Properly check napi_complete_done() return value in order to decide
    whether to re-enable IRQs or not in amd-xgbe driver, from Thomas
    Lendacky.

11) Fix double free of hwmon device in marvell phy driver, from Andrew
    Lunn.

12) Don't crash on malformed netlink attributes in act_connmark, from
    Etienne Noss.

13) Don't remove routes with a higher metric in ipv6 ECMP route replace,
    from Sabrina Dubroca.

14) Don't write into a cloned SKB in ipv6 fragmentation handling, from
    Florian Westphal.

15) Fix routing redirect races in dccp and tcp, basically the ICMP
    handler can't modify the socket's cached route in it's locked by the
    user at this moment. From Jon Maxwell.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (108 commits)
  qed: Enable iSCSI Out-of-Order
  qed: Correct out-of-bound access in OOO history
  qed: Fix interrupt flags on Rx LL2
  qed: Free previous connections when releasing iSCSI
  qed: Fix mapping leak on LL2 rx flow
  qed: Prevent creation of too-big u32-chains
  qed: Align CIDs according to DORQ requirement
  mlxsw: reg: Fix SPVMLR max record count
  mlxsw: reg: Fix SPVM max record count
  net: Resend IGMP memberships upon peer notification.
  dccp: fix memory leak during tear-down of unsuccessful connection request
  tun: fix premature POLLOUT notification on tun devices
  dccp/tcp: fix routing redirect race
  ucc/hdlc: fix two little issue
  vxlan: fix ovs support
  net: use net->count to check whether a netns is alive or not
  bridge: drop netfilter fake rtable unconditionally
  ipv6: avoid write to a possibly cloned skb
  net: wimax/i2400m: fix NULL-deref at probe
  isdn/gigaset: fix NULL-deref at probe
  ...

Pull cgroup fixes from Tejun Heo:
 "Three cgroup fixes.  Nothing critical:

   - the pids controller could trigger suspicious RCU warning
     spuriously. Fixed.

   - in the debug controller, %p -> %pK to protect kernel pointer
     from getting exposed.

   - documentation formatting fix"

* 'for-4.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroups: censor kernel pointer in debug files
  cgroup/pids: remove spurious suspicious RCU usage warning
  cgroup: Fix indenting in PID controller documentation

Pull libata fixes from Tejun Heo:
 "Three libata fixes:

   - fix for a circular reference bug in sysfs code which prevented
     pata_legacy devices from being released after probe failure, which
     in turn prevented devres from releasing the associated resources.

   - drop spurious WARN in the command issue path which can be triggered
     by a legitimate passthrough command.

   - an ahci_qoriq specific fix"

* 'for-4.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
  ahci: qoriq: correct the sata ecc setting error
  libata: drop WARN from protocol error in ata_sff_qc_issue()
  libata: transport: Remove circular dependency at free time

Pull workqueue fix from Tejun Heo:
 "If a delayed work is queued with NULL @wq, workqueue code explodes
  after the timer expires at which point it's difficult to tell who the
  culprit was.

  This actually happened and the offender was net/smc this time.

  Add an explicit sanity check for it in the queueing path"

* 'for-4.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: trigger WARN if queue_delayed_work() is called with NULL @wq

Pull percpu fixes from Tejun Heo:

 - the allocation path was updating pcpu_nr_empty_pop_pages without the
   required locking which can lead to incorrect handling of empty chunks
   (e.g. keeping too many around), which is buggy but shouldn't lead to
   critical failures. Fixed by adding the locking

 - a trivial patch to drop an unused param from pcpu_get_pages()

* 'for-4.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
  percpu: remove unused chunk_alloc parameter from pcpu_get_pages()
  percpu: acquire pcpu_lock when updating pcpu_nr_empty_pop_pages

Yuval Mintz says:

====================
qed: Fixes series

This address several different issues in qed.
The more significant portions:

Patch #1 would cause timeout when qedr utilizes the highest
CIDs availble for it [or when future qede adapters would utilize
queues in some constellations].

Patch #4 fixes a leak of mapped addresses; When iommu is enabled,
offloaded storage protocols might eventually run out of resources
and fail to map additional buffers.

Patches #6,#7 were missing in the initial iSCSI infrastructure
submissions, and would hamper qedi's stability when it reaches
out-of-order scenarios.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Missing in the initial submission, qed fails to propagate qedi's
request to enable OOO to firmware.

Fixes: fc831825 ("qed: Add support for hardware offloaded iSCSI")
Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Need to set the number of entries in database, otherwise the logic
would quickly surpass the array.

Fixes: 1d6cff4f ("qed: Add iSCSI out of order packet handling")
Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Before iterating over the the LL2 Rx ring, the ring's
spinlock is taken via spin_lock_irqsave().
The actual processing of the packet [including handling
by the protocol driver] is done without said lock,
so qed releases the spinlock and re-claims it afterwards.

Problem is that the final spin_lock_irqrestore() at the end
of the iteration uses the original flags saved from the
initial irqsave() instead of the flags from the most recent
irqsave(). So it's possible that the interrupt status would
be incorrect at the end of the processing.

Fixes: 0a7fb11c ("qed: Add Light L2 support");
CC: Ram Amrani <Ram.Amrani@cavium.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fixes: fc831825 ("qed: Add support for hardware offloaded iSCSI")
Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When receiving an Rx LL2 packet, qed fails to unmap the previous buffer.

Fixes: 0a7fb11c ("qed: Add Light L2 support");
Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Current Logic would allow the creation of a chain with U32_MAX + 1
elements, when the actual maximum supported by the driver infrastructure
is U32_MAX.

Fixes: a91eb52a ("qed: Revisit chain implementation")
Signed-off-by: Tomer Tayar <Tomer.Tayar@cavium.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The Doorbell HW block can be configured at a granularity
of 16 x CIDs, so we need to make sure that the actual number
of CIDs configured would be a multiplication of 16.

Today, when RoCE is enabled - given that the number is unaligned,
doorbelling the higher CIDs would fail to reach the firmware and
would eventually timeout.

Fixes: dbb799c3 ("qed: Initialize hardware for new protocols")
Signed-off-by: Ram Amrani <Ram.Amrani@cavium.com>
Signed-off-by: Yuval Mintz <Yuval.Mintz@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>