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6 years agoMerge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Sun, 14 Jan 2018 17:51:25 +0000 (09:51 -0800)]
Merge branch 'x86-pti-for-linus' of git://git./linux/kernel/git/tip/tip

Pull x86 pti updates from Thomas Gleixner:
 "This contains:

   - a PTI bugfix to avoid setting reserved CR3 bits when PCID is
     disabled. This seems to cause issues on a virtual machine at least
     and is incorrect according to the AMD manual.

   - a PTI bugfix which disables the perf BTS facility if PTI is
     enabled. The BTS AUX buffer is not globally visible and causes the
     CPU to fault when the mapping disappears on switching CR3 to user
     space. A full fix which restores BTS on PTI is non trivial and will
     be worked on.

   - PTI bugfixes for EFI and trusted boot which make sure that the user
     space visible page table entries have the NX bit cleared

   - removal of dead code in the PTI pagetable setup functions

   - add PTI documentation

   - add a selftest for vsyscall to verify that the kernel actually
     implements what it advertises.

   - a sysfs interface to expose vulnerability and mitigation
     information so there is a coherent way for users to retrieve the
     status.

   - the initial spectre_v2 mitigations, aka retpoline:

      + The necessary ASM thunk and compiler support

      + The ASM variants of retpoline and the conversion of affected ASM
        code

      + Make LFENCE serializing on AMD so it can be used as speculation
        trap

      + The RSB fill after vmexit

   - initial objtool support for retpoline

  As I said in the status mail this is the most of the set of patches
  which should go into 4.15 except two straight forward patches still on
  hold:

   - the retpoline add on of LFENCE which waits for ACKs

   - the RSB fill after context switch

  Both should be ready to go early next week and with that we'll have
  covered the major holes of spectre_v2 and go back to normality"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (28 commits)
  x86,perf: Disable intel_bts when PTI
  security/Kconfig: Correct the Documentation reference for PTI
  x86/pti: Fix !PCID and sanitize defines
  selftests/x86: Add test_vsyscall
  x86/retpoline: Fill return stack buffer on vmexit
  x86/retpoline/irq32: Convert assembler indirect jumps
  x86/retpoline/checksum32: Convert assembler indirect jumps
  x86/retpoline/xen: Convert Xen hypercall indirect jumps
  x86/retpoline/hyperv: Convert assembler indirect jumps
  x86/retpoline/ftrace: Convert ftrace assembler indirect jumps
  x86/retpoline/entry: Convert entry assembler indirect jumps
  x86/retpoline/crypto: Convert crypto assembler indirect jumps
  x86/spectre: Add boot time option to select Spectre v2 mitigation
  x86/retpoline: Add initial retpoline support
  objtool: Allow alternatives to be ignored
  objtool: Detect jumps to retpoline thunks
  x86/pti: Make unpoison of pgd for trusted boot work for real
  x86/alternatives: Fix optimize_nops() checking
  sysfs/cpu: Fix typos in vulnerability documentation
  x86/cpu/AMD: Use LFENCE_RDTSC in preference to MFENCE_RDTSC
  ...

6 years agox86,perf: Disable intel_bts when PTI
Peter Zijlstra [Sun, 14 Jan 2018 10:27:13 +0000 (11:27 +0100)]
x86,perf: Disable intel_bts when PTI

The intel_bts driver does not use the 'normal' BTS buffer which is exposed
through the cpu_entry_area but instead uses the memory allocated for the
perf AUX buffer.

This obviously comes apart when using PTI because then the kernel mapping;
which includes that AUX buffer memory; disappears. Fixing this requires to
expose a mapping which is visible in all context and that's not trivial.

As a quick fix disable this driver when PTI is enabled to prevent
malfunction.

Fixes: 385ce0ea4c07 ("x86/mm/pti: Add Kconfig")
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Reported-by: Robert Święcki <robert@swiecki.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: greg@kroah.com
Cc: hughd@google.com
Cc: luto@amacapital.net
Cc: Vince Weaver <vince@deater.net>
Cc: torvalds@linux-foundation.org
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180114102713.GB6166@worktop.programming.kicks-ass.net
6 years agosecurity/Kconfig: Correct the Documentation reference for PTI
W. Trevor King [Fri, 12 Jan 2018 23:24:59 +0000 (15:24 -0800)]
security/Kconfig: Correct the Documentation reference for PTI

When the config option for PTI was added a reference to documentation was
added as well. But the documentation did not exist at that point. The final
documentation has a different file name.

Fix it up to point to the proper file.

Fixes: 385ce0ea ("x86/mm/pti: Add Kconfig")
Signed-off-by: W. Trevor King <wking@tremily.us>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-mm@kvack.org
Cc: linux-security-module@vger.kernel.org
Cc: James Morris <james.l.morris@oracle.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/3009cc8ccbddcd897ec1e0cb6dda524929de0d14.1515799398.git.wking@tremily.us
6 years agox86/pti: Fix !PCID and sanitize defines
Thomas Gleixner [Sat, 13 Jan 2018 23:23:57 +0000 (00:23 +0100)]
x86/pti: Fix !PCID and sanitize defines

The switch to the user space page tables in the low level ASM code sets
unconditionally bit 12 and bit 11 of CR3. Bit 12 is switching the base
address of the page directory to the user part, bit 11 is switching the
PCID to the PCID associated with the user page tables.

This fails on a machine which lacks PCID support because bit 11 is set in
CR3. Bit 11 is reserved when PCID is inactive.

While the Intel SDM claims that the reserved bits are ignored when PCID is
disabled, the AMD APM states that they should be cleared.

This went unnoticed as the AMD APM was not checked when the code was
developed and reviewed and test systems with Intel CPUs never failed to
boot. The report is against a Centos 6 host where the guest fails to boot,
so it's not yet clear whether this is a virt issue or can happen on real
hardware too, but thats irrelevant as the AMD APM clearly ask for clearing
the reserved bits.

Make sure that on non PCID machines bit 11 is not set by the page table
switching code.

Andy suggested to rename the related bits and masks so they are clearly
describing what they should be used for, which is done as well for clarity.

That split could have been done with alternatives but the macro hell is
horrible and ugly. This can be done on top if someone cares to remove the
extra orq. For now it's a straight forward fix.

Fixes: 6fd166aae78c ("x86/mm: Use/Fix PCID to optimize user/kernel switches")
Reported-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable <stable@vger.kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Willy Tarreau <w@1wt.eu>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801140009150.2371@nanos
6 years agoMerge tag 'usb-4.15-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Linus Torvalds [Sat, 13 Jan 2018 22:10:32 +0000 (14:10 -0800)]
Merge tag 'usb-4.15-rc8' of git://git./linux/kernel/git/gregkh/usb

Pull USB fixes from Greg KH:
 "Here are some small USB fixes and device ids for 4.15-rc8

  Nothing major, small fixes for various devices, some resolutions for
  bugs found by fuzzers, and the usual handful of new device ids.

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

* tag 'usb-4.15-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  Documentation: usb: fix typo in UVC gadgetfs config command
  usb: misc: usb3503: make sure reset is low for at least 100us
  uas: ignore UAS for Norelsys NS1068(X) chips
  USB: UDC core: fix double-free in usb_add_gadget_udc_release
  USB: fix usbmon BUG trigger
  usbip: vudc_tx: fix v_send_ret_submit() vulnerability to null xfer buffer
  usbip: remove kernel addresses from usb device and urb debug msgs
  usbip: fix vudc_rx: harden CMD_SUBMIT path to handle malicious input
  USB: serial: cp210x: add new device ID ELV ALC 8xxx
  USB: serial: cp210x: add IDs for LifeScan OneTouch Verio IQ

6 years agoMerge tag 'staging-4.15-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh...
Linus Torvalds [Sat, 13 Jan 2018 22:04:06 +0000 (14:04 -0800)]
Merge tag 'staging-4.15-rc8' of git://git./linux/kernel/git/gregkh/staging

Pull staging driver fix from Greg KH:
 "Here is a single android ashmem bugfix that resolves a reported issue
  in that interface. It's been in linux-next this week with no reported
  issues"

* tag 'staging-4.15-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: android: ashmem: fix a race condition in ASHMEM_SET_SIZE ioctl

6 years agoMerge tag 'char-misc-4.15-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregk...
Linus Torvalds [Sat, 13 Jan 2018 22:01:59 +0000 (14:01 -0800)]
Merge tag 'char-misc-4.15-rc8' of git://git./linux/kernel/git/gregkh/char-misc

Pull char/misc fixes from Greg KH:
 "Here are two bugfixes for some driver bugs for 4.15-rc8

  The first is a bluetooth security bug that has been ignored by the
  Bluetooth developers for months for no obvious reason at all, so I've
  taken it through my tree.

  The second is a simple double-free bug in the mux subsystem.

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

* tag 'char-misc-4.15-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  mux: core: fix double get_device()
  Bluetooth: Prevent stack info leak from the EFS element.

6 years agoMerge tag 'kbuild-fixes-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masah...
Linus Torvalds [Sat, 13 Jan 2018 21:24:56 +0000 (13:24 -0800)]
Merge tag 'kbuild-fixes-v4.15' of git://git./linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - fix cross-compilation for architectures that setup CROSS_COMPILE in
   their arch Makefile

 - fix Kconfig rational operators for bool / tristate

 - drop a gperf-generated file from .gitignore

* tag 'kbuild-fixes-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  genksyms: drop *.hash.c from .gitignore
  kconfig: fix relational operators for bool and tristate symbols
  kbuild: move cc-option and cc-disable-warning after incl. arch Makefile

6 years agoMerge tag 'apparmor-pr-2018-01-12' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Sat, 13 Jan 2018 21:18:15 +0000 (13:18 -0800)]
Merge tag 'apparmor-pr-2018-01-12' of git://git./linux/kernel/git/jj/linux-apparmor

Pull apparmor regression fixes from John Johansen:
 "This fixes a couple bugs I have been working with Matthew Garrett on
  this week. Specifically a regression in the handling of a conflicting
  profile attachment and label match restrictions for ptrace when
  profiles are stacked.

  Summary:

   - fix ptrace label match when matching stacked labels

   - fix regression in profile conflict logic"

* tag 'apparmor-pr-2018-01-12' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor:
  apparmor: Fix regression in profile conflict logic
  apparmor: fix ptrace label match when matching stacked labels

6 years agoMerge tag 'pci-v4.15-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaa...
Linus Torvalds [Sat, 13 Jan 2018 21:14:54 +0000 (13:14 -0800)]
Merge tag 'pci-v4.15-fixes-2' of git://git./linux/kernel/git/helgaas/pci

Pull PCI fixes from Bjorn Helgaas:
 "Fix AMD boot regression due to 64-bit window conflicting with system
  memory (Christian König)"

* tag 'pci-v4.15-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  x86/PCI: Move and shrink AMD 64-bit window to avoid conflict
  x86/PCI: Add "pci=big_root_window" option for AMD 64-bit windows

6 years agoMerge branch 'akpm' (patches from Andrew)
Linus Torvalds [Sat, 13 Jan 2018 19:07:55 +0000 (11:07 -0800)]
Merge branch 'akpm' (patches from Andrew)

Merge misc fixlets from Andrew Morton:
 "4 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  tools/objtool/Makefile: don't assume sync-check.sh is executable
  kdump: write correct address of mem_section into vmcoreinfo
  kmemleak: allow to coexist with fault injection
  MAINTAINERS, nilfs2: change project home URLs

6 years agotools/objtool/Makefile: don't assume sync-check.sh is executable
Andrew Morton [Sat, 13 Jan 2018 00:53:17 +0000 (16:53 -0800)]
tools/objtool/Makefile: don't assume sync-check.sh is executable

patch(1) loses the x bit.  So if a user follows our patching
instructions in Documentation/admin-guide/README.rst, their kernel will
not compile.

Fixes: 3bd51c5a371de ("objtool: Move kernel headers/code sync check to a script")
Reported-by: Nicolas Bock <nicolasbock@gentoo.org>
Reported-by Joakim Tjernlund <Joakim.Tjernlund@infinera.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agokdump: write correct address of mem_section into vmcoreinfo
Kirill A. Shutemov [Sat, 13 Jan 2018 00:53:14 +0000 (16:53 -0800)]
kdump: write correct address of mem_section into vmcoreinfo

Depending on configuration mem_section can now be an array or a pointer
to an array allocated dynamically.  In most cases, we can continue to
refer to it as 'mem_section' regardless of what it is.

But there's one exception: '&mem_section' means "address of the array"
if mem_section is an array, but if mem_section is a pointer, it would
mean "address of the pointer".

We've stepped onto this in kdump code.  VMCOREINFO_SYMBOL(mem_section)
writes down address of pointer into vmcoreinfo, not array as we wanted.

Let's introduce VMCOREINFO_SYMBOL_ARRAY() that would handle the
situation correctly for both cases.

Link: http://lkml.kernel.org/r/20180112162532.35896-1-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Fixes: 83e3c48729d9 ("mm/sparsemem: Allocate mem_section at runtime for CONFIG_SPARSEMEM_EXTREME=y")
Acked-by: Baoquan He <bhe@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Dave Young <dyoung@redhat.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agokmemleak: allow to coexist with fault injection
Dmitry Vyukov [Sat, 13 Jan 2018 00:53:10 +0000 (16:53 -0800)]
kmemleak: allow to coexist with fault injection

kmemleak does one slab allocation per user allocation.  So if slab fault
injection is enabled to any degree, kmemleak instantly fails to allocate
and turns itself off.  However, it's useful to use kmemleak with fault
injection to find leaks on error paths.  On the other hand, checking
kmemleak itself is not so useful because (1) it's a debugging tool and
(2) it has a very regular allocation pattern (basically a single
allocation site, so it either works or not).

Turn off fault injection for kmemleak allocations.

Link: http://lkml.kernel.org/r/20180109192243.19316-1-dvyukov@google.com
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agoMAINTAINERS, nilfs2: change project home URLs
Ryusuke Konishi [Sat, 13 Jan 2018 00:53:07 +0000 (16:53 -0800)]
MAINTAINERS, nilfs2: change project home URLs

The domain of NILFS project home was changed to "nilfs.sourceforge.io"
to enable https access (the previous domain "nilfs.sourceforge.net" is
redirected to the new one).  Modify URLs of the project home to reflect
this change and to replace their protocol from http to https.

Link: http://lkml.kernel.org/r/1515416141-5614-1-git-send-email-konishi.ryusuke@lab.ntt.co.jp
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agogenksyms: drop *.hash.c from .gitignore
Masahiro Yamada [Thu, 11 Jan 2018 09:28:08 +0000 (18:28 +0900)]
genksyms: drop *.hash.c from .gitignore

This is a left-over of commit bb3290d91695 ("Remove gperf usage from
toolchain").

We do not generate a hash function any more.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
6 years agoselftests/x86: Add test_vsyscall
Andy Lutomirski [Fri, 12 Jan 2018 01:16:51 +0000 (17:16 -0800)]
selftests/x86: Add test_vsyscall

This tests that the vsyscall entries do what they're expected to do.
It also confirms that attempts to read the vsyscall page behave as
expected.

If changes are made to the vsyscall code or its memory map handling,
running this test in all three of vsyscall=none, vsyscall=emulate,
and vsyscall=native are helpful.

(Because it's easy, this also compares the vsyscall results to their
 vDSO equivalents.)

Note to KAISER backporters: please test this under all three
vsyscall modes.  Also, in the emulate and native modes, make sure
that test_vsyscall_64 agrees with the command line or config
option as to which mode you're in.  It's quite easy to mess up
the kernel such that native mode accidentally emulates
or vice versa.

Greg, etc: please backport this to all your Meltdown-patched
kernels.  It'll help make sure the patches didn't regress
vsyscalls.

CSigned-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/2b9c5a174c1d60fd7774461d518aa75598b1d8fd.1515719552.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
6 years agoapparmor: Fix regression in profile conflict logic
Matthew Garrett [Thu, 11 Jan 2018 21:07:54 +0000 (13:07 -0800)]
apparmor: Fix regression in profile conflict logic

The intended behaviour in apparmor profile matching is to flag a
conflict if two profiles match equally well. However, right now a
conflict is generated if another profile has the same match length even
if that profile doesn't actually match. Fix the logic so we only
generate a conflict if the profiles match.

Fixes: 844b8292b631 ("apparmor: ensure that undecidable profile attachments fail")
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
6 years agoapparmor: fix ptrace label match when matching stacked labels
John Johansen [Sat, 9 Dec 2017 01:43:18 +0000 (17:43 -0800)]
apparmor: fix ptrace label match when matching stacked labels

Given a label with a profile stack of
  A//&B or A//&C ...

A ptrace rule should be able to specify a generic trace pattern with
a rule like

  ptrace trace A//&**,

however this is failing because while the correct label match routine
is called, it is being done post label decomposition so it is always
being done against a profile instead of the stacked label.

To fix this refactor the cross check to pass the full peer label in to
the label_match.

Fixes: 290f458a4f16 ("apparmor: allow ptrace checks to be finer grained than just capability")
Cc: Stable <stable@vger.kernel.org>
Reported-by: Matthew Garrett <mjg59@google.com>
Tested-by: Matthew Garrett <mjg59@google.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>
6 years agoMerge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Fri, 12 Jan 2018 18:32:11 +0000 (10:32 -0800)]
Merge branch 'x86-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull x86 fixes from Ingo Molnar:
 "Two pending (non-PTI) x86 fixes:

   - an Intel-MID crash fix

   - and an Intel microcode loader blacklist quirk to avoid a
     problematic revision"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/platform/intel-mid: Revert "Make 'bt_sfi_data' const"
  x86/microcode/intel: Extend BDW late-loading with a revision check

6 years agoMerge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Fri, 12 Jan 2018 18:23:59 +0000 (10:23 -0800)]
Merge branch 'sched-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull scheduler fixes from Ingo Molnar:
 "A Kconfig fix, a build fix and a membarrier bug fix"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  membarrier: Disable preemption when calling smp_call_function_many()
  sched/isolation: Make CONFIG_CPU_ISOLATION=y depend on SMP or COMPILE_TEST
  ia64, sched/cputime: Fix build error if CONFIG_VIRT_CPU_ACCOUNTING_NATIVE=y

6 years agoMerge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Fri, 12 Jan 2018 18:14:09 +0000 (10:14 -0800)]
Merge branch 'locking-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull locking fixes from Ingo Molnar:
 "No functional effects intended: removes leftovers from recent lockdep
  and refcounts work"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/refcounts: Remove stale comment from the ARCH_HAS_REFCOUNT Kconfig entry
  locking/lockdep: Remove cross-release leftovers
  locking/Documentation: Remove stale crossrelease_fullstack parameter

6 years agoMerge tag 'for-linus-4.15-rc8-tag' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Fri, 12 Jan 2018 18:00:15 +0000 (10:00 -0800)]
Merge tag 'for-linus-4.15-rc8-tag' of git://git./linux/kernel/git/xen/tip

Pull xen fixes from Juergen Gross:
 "This contains two build fixes for clang and two fixes for rather
  unlikely situations in the Xen gntdev driver"

* tag 'for-linus-4.15-rc8-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/gntdev: Fix partial gntdev_mmap() cleanup
  xen/gntdev: Fix off-by-one error when unmapping with holes
  x86: xen: remove the use of VLAIS
  x86/xen/time: fix section mismatch for xen_init_time_ops()

6 years agoMerge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Linus Torvalds [Fri, 12 Jan 2018 17:56:52 +0000 (09:56 -0800)]
Merge tag 'for-linus' of git://git./virt/kvm/kvm

Pull KVM fixes from Paolo Bonzini:
 "PPC:
   - user-triggerable use-after-free in HPT resizing
   - stale TLB entries in the guest
   - trap-and-emulate (PR) KVM guests failing to start under pHyp

  x86:
   - Another "Spectre" fix.
   - async pagefault fix
   - Revert an old fix for x86 nested virtualization, which turned out
     to do more harm than good
   - Check shrinker registration return code, to avoid warnings from
     upcoming 4.16 -mm patches"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: Add memory barrier on vmcs field lookup
  KVM: x86: emulate #UD while in guest mode
  x86: kvm: propagate register_shrinker return code
  KVM MMU: check pending exception before injecting APF
  KVM: PPC: Book3S HV: Always flush TLB in kvmppc_alloc_reset_hpt()
  KVM: PPC: Book3S PR: Fix WIMG handling under pHyp
  KVM: PPC: Book3S HV: Fix use after free in case of multiple resize requests
  KVM: PPC: Book3S HV: Drop prepare_done from struct kvm_resize_hpt

6 years agoMerge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Linus Torvalds [Fri, 12 Jan 2018 17:47:58 +0000 (09:47 -0800)]
Merge branch 'linus' of git://git./linux/kernel/git/herbert/crypto-2.6

Pull crypto fix from Herbert Xu:
 "This fixes a NULL pointer dereference in crypto_remove_spawns that can
  be triggered through af_alg"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: algapi - fix NULL dereference in crypto_remove_spawns()

6 years agoMerge tag 'mmc-v4.15-rc2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc
Linus Torvalds [Fri, 12 Jan 2018 17:34:20 +0000 (09:34 -0800)]
Merge tag 'mmc-v4.15-rc2-2' of git://git./linux/kernel/git/ulfh/mmc

Pull MMC host fixes from Ulf Hansson:

 - s3mci: mark debug_regs[] as static

 - renesas_sdhi: Add MODULE_LICENSE

* tag 'mmc-v4.15-rc2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
  mmc: s3mci: mark debug_regs[] as static
  mmc: renesas_sdhi: Add MODULE_LICENSE

6 years agoMerge tag 'drm-fixes-for-v4.15-rc8' of git://people.freedesktop.org/~airlied/linux
Linus Torvalds [Fri, 12 Jan 2018 17:28:28 +0000 (09:28 -0800)]
Merge tag 'drm-fixes-for-v4.15-rc8' of git://people.freedesktop.org/~airlied/linux

Pull drm fixes from Dave Airlie:

 - Nouveau: regression fix

 - Tegra: regression fix

 - vmwgfx: crasher + freed data leak

 - i915: KASAN use after free fix, whitelist register to avoid hang fix,
   GVT fixes

 - vc4: irq/pm fix

* tag 'drm-fixes-for-v4.15-rc8' of git://people.freedesktop.org/~airlied/linux:
  drm/i915: Don't adjust priority on an already signaled fence
  drm/i915: Whitelist SLICE_COMMON_ECO_CHICKEN1 on Geminilake.
  drm/vmwgfx: Potential off by one in vmw_view_add()
  drm/tegra: sor: Fix hang on Tegra124 eDP
  drm/vmwgfx: Don't cache framebuffer maps
  drm/nouveau/disp/gf119: add missing drive vfunc ptr
  drm/i915/gvt: Fix stack-out-of-bounds bug in cmd parser
  drm/i915/gvt: Clear the shadow page table entry after post-sync
  drm/vc4: Move IRQ enable to PM path

6 years agox86/retpoline: Fill return stack buffer on vmexit
David Woodhouse [Fri, 12 Jan 2018 11:11:27 +0000 (11:11 +0000)]
x86/retpoline: Fill return stack buffer on vmexit

In accordance with the Intel and AMD documentation, we need to overwrite
all entries in the RSB on exiting a guest, to prevent malicious branch
target predictions from affecting the host kernel. This is needed both
for retpoline and for IBRS.

[ak: numbers again for the RSB stuffing labels]

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: thomas.lendacky@amd.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: https://lkml.kernel.org/r/1515755487-8524-1-git-send-email-dwmw@amazon.co.uk
6 years agoMerge tag 'drm-intel-fixes-2018-01-11-1' of git://anongit.freedesktop.org/drm/drm...
Dave Airlie [Fri, 12 Jan 2018 01:48:06 +0000 (11:48 +1000)]
Merge tag 'drm-intel-fixes-2018-01-11-1' of git://anongit.freedesktop.org/drm/drm-intel into drm-fixes

Hopefully final drm/i915 fixes for v4.15:
- Fix a KASAN reported use after free
- Whitelist a register to avoid hangs
- GVT fixes

* tag 'drm-intel-fixes-2018-01-11-1' of git://anongit.freedesktop.org/drm/drm-intel:
  drm/i915: Don't adjust priority on an already signaled fence
  drm/i915: Whitelist SLICE_COMMON_ECO_CHICKEN1 on Geminilake.
  drm/i915/gvt: Fix stack-out-of-bounds bug in cmd parser
  drm/i915/gvt: Clear the shadow page table entry after post-sync

6 years agoMerge branch 'vmwgfx-fixes-4.15' of git://people.freedesktop.org/~thomash/linux into...
Dave Airlie [Fri, 12 Jan 2018 01:47:40 +0000 (11:47 +1000)]
Merge branch 'vmwgfx-fixes-4.15' of git://people.freedesktop.org/~thomash/linux into drm-fixes

Two important fixes for vmwgfx.
The off-by-one fix could cause a malicious user to potentially crash the
kernel.
The framebuffer map cache fix can under some circumstances enable a user to
read from or write to freed pages.

* 'vmwgfx-fixes-4.15' of git://people.freedesktop.org/~thomash/linux:
  drm/vmwgfx: Potential off by one in vmw_view_add()
  drm/vmwgfx: Don't cache framebuffer maps

6 years agoMerge tag 'drm/tegra/for-4.15-rc8' of git://anongit.freedesktop.org/tegra/linux into...
Dave Airlie [Fri, 12 Jan 2018 01:47:11 +0000 (11:47 +1000)]
Merge tag 'drm/tegra/for-4.15-rc8' of git://anongit.freedesktop.org/tegra/linux into drm-fixes

drm/tegra: Fixes for v4.15-rc8

A single fix for a Tegra124 eDP regression introduced by the SOR changes
in v4.15-rc1.

* tag 'drm/tegra/for-4.15-rc8' of git://anongit.freedesktop.org/tegra/linux:
  drm/tegra: sor: Fix hang on Tegra124 eDP

6 years agoMerge tag 'ceph-for-4.15-rc8' of git://github.com/ceph/ceph-client
Linus Torvalds [Fri, 12 Jan 2018 00:57:32 +0000 (16:57 -0800)]
Merge tag 'ceph-for-4.15-rc8' of git://github.com/ceph/ceph-client

Pull ceph fixes from Ilya Dryomov:
 "Two rbd fixes for 4.12 and 4.2 issues respectively, marked for
  stable"

* tag 'ceph-for-4.15-rc8' of git://github.com/ceph/ceph-client:
  rbd: set max_segments to USHRT_MAX
  rbd: reacquire lock should update lock owner client id

6 years agoMerge tag 'gpio-v4.15-4' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw...
Linus Torvalds [Fri, 12 Jan 2018 00:54:35 +0000 (16:54 -0800)]
Merge tag 'gpio-v4.15-4' of git://git./linux/kernel/git/linusw/linux-gpio

Pull GPIO fix from Linus Walleij:
 "Fix a raw vs elaborate GPIO descriptor bug introduced by yours truly"

* tag 'gpio-v4.15-4' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
  gpio: Add missing open drain/source handling to gpiod_set_value_cansleep()

6 years agox86/retpoline/irq32: Convert assembler indirect jumps
Andi Kleen [Thu, 11 Jan 2018 21:46:33 +0000 (21:46 +0000)]
x86/retpoline/irq32: Convert assembler indirect jumps

Convert all indirect jumps in 32bit irq inline asm code to use non
speculative sequences.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: thomas.lendacky@amd.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: https://lkml.kernel.org/r/1515707194-20531-12-git-send-email-dwmw@amazon.co.uk
6 years agox86/retpoline/checksum32: Convert assembler indirect jumps
David Woodhouse [Thu, 11 Jan 2018 21:46:32 +0000 (21:46 +0000)]
x86/retpoline/checksum32: Convert assembler indirect jumps

Convert all indirect jumps in 32bit checksum assembler code to use
non-speculative sequences when CONFIG_RETPOLINE is enabled.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: thomas.lendacky@amd.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: https://lkml.kernel.org/r/1515707194-20531-11-git-send-email-dwmw@amazon.co.uk
6 years agox86/retpoline/xen: Convert Xen hypercall indirect jumps
David Woodhouse [Thu, 11 Jan 2018 21:46:31 +0000 (21:46 +0000)]
x86/retpoline/xen: Convert Xen hypercall indirect jumps

Convert indirect call in Xen hypercall to use non-speculative sequence,
when CONFIG_RETPOLINE is enabled.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: thomas.lendacky@amd.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: https://lkml.kernel.org/r/1515707194-20531-10-git-send-email-dwmw@amazon.co.uk
6 years agox86/retpoline/hyperv: Convert assembler indirect jumps
David Woodhouse [Thu, 11 Jan 2018 21:46:30 +0000 (21:46 +0000)]
x86/retpoline/hyperv: Convert assembler indirect jumps

Convert all indirect jumps in hyperv inline asm code to use non-speculative
sequences when CONFIG_RETPOLINE is enabled.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: thomas.lendacky@amd.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: https://lkml.kernel.org/r/1515707194-20531-9-git-send-email-dwmw@amazon.co.uk
6 years agox86/retpoline/ftrace: Convert ftrace assembler indirect jumps
David Woodhouse [Thu, 11 Jan 2018 21:46:29 +0000 (21:46 +0000)]
x86/retpoline/ftrace: Convert ftrace assembler indirect jumps

Convert all indirect jumps in ftrace assembler code to use non-speculative
sequences when CONFIG_RETPOLINE is enabled.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: thomas.lendacky@amd.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: https://lkml.kernel.org/r/1515707194-20531-8-git-send-email-dwmw@amazon.co.uk
6 years agox86/retpoline/entry: Convert entry assembler indirect jumps
David Woodhouse [Thu, 11 Jan 2018 21:46:28 +0000 (21:46 +0000)]
x86/retpoline/entry: Convert entry assembler indirect jumps

Convert indirect jumps in core 32/64bit entry assembler code to use
non-speculative sequences when CONFIG_RETPOLINE is enabled.

Don't use CALL_NOSPEC in entry_SYSCALL_64_fastpath because the return
address after the 'call' instruction must be *precisely* at the
.Lentry_SYSCALL_64_after_fastpath label for stub_ptregs_64 to work,
and the use of alternatives will mess that up unless we play horrid
games to prepend with NOPs and make the variants the same length. It's
not worth it; in the case where we ALTERNATIVE out the retpoline, the
first instruction at __x86.indirect_thunk.rax is going to be a bare
jmp *%rax anyway.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: thomas.lendacky@amd.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: https://lkml.kernel.org/r/1515707194-20531-7-git-send-email-dwmw@amazon.co.uk
6 years agox86/retpoline/crypto: Convert crypto assembler indirect jumps
David Woodhouse [Thu, 11 Jan 2018 21:46:27 +0000 (21:46 +0000)]
x86/retpoline/crypto: Convert crypto assembler indirect jumps

Convert all indirect jumps in crypto assembler code to use non-speculative
sequences when CONFIG_RETPOLINE is enabled.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: thomas.lendacky@amd.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: https://lkml.kernel.org/r/1515707194-20531-6-git-send-email-dwmw@amazon.co.uk
6 years agox86/spectre: Add boot time option to select Spectre v2 mitigation
David Woodhouse [Thu, 11 Jan 2018 21:46:26 +0000 (21:46 +0000)]
x86/spectre: Add boot time option to select Spectre v2 mitigation

Add a spectre_v2= option to select the mitigation used for the indirect
branch speculation vulnerability.

Currently, the only option available is retpoline, in its various forms.
This will be expanded to cover the new IBRS/IBPB microcode features.

The RETPOLINE_AMD feature relies on a serializing LFENCE for speculation
control. For AMD hardware, only set RETPOLINE_AMD if LFENCE is a
serializing instruction, which is indicated by the LFENCE_RDTSC feature.

[ tglx: Folded back the LFENCE/AMD fixes and reworked it so IBRS
   integration becomes simple ]

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: thomas.lendacky@amd.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: https://lkml.kernel.org/r/1515707194-20531-5-git-send-email-dwmw@amazon.co.uk
6 years agox86/retpoline: Add initial retpoline support
David Woodhouse [Thu, 11 Jan 2018 21:46:25 +0000 (21:46 +0000)]
x86/retpoline: Add initial retpoline support

Enable the use of -mindirect-branch=thunk-extern in newer GCC, and provide
the corresponding thunks. Provide assembler macros for invoking the thunks
in the same way that GCC does, from native and inline assembler.

This adds X86_FEATURE_RETPOLINE and sets it by default on all CPUs. In
some circumstances, IBRS microcode features may be used instead, and the
retpoline can be disabled.

On AMD CPUs if lfence is serialising, the retpoline can be dramatically
simplified to a simple "lfence; jmp *\reg". A future patch, after it has
been verified that lfence really is serialising in all circumstances, can
enable this by setting the X86_FEATURE_RETPOLINE_AMD feature bit in addition
to X86_FEATURE_RETPOLINE.

Do not align the retpoline in the altinstr section, because there is no
guarantee that it stays aligned when it's copied over the oldinstr during
alternative patching.

[ Andi Kleen: Rename the macros, add CONFIG_RETPOLINE option, export thunks]
[ tglx: Put actual function CALL/JMP in front of the macros, convert to
   symbolic labels ]
[ dwmw2: Convert back to numeric labels, merge objtool fixes ]

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: thomas.lendacky@amd.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: https://lkml.kernel.org/r/1515707194-20531-4-git-send-email-dwmw@amazon.co.uk
6 years agoobjtool: Allow alternatives to be ignored
Josh Poimboeuf [Thu, 11 Jan 2018 21:46:24 +0000 (21:46 +0000)]
objtool: Allow alternatives to be ignored

Getting objtool to understand retpolines is going to be a bit of a
challenge.  For now, take advantage of the fact that retpolines are
patched in with alternatives.  Just read the original (sane)
non-alternative instruction, and ignore the patched-in retpoline.

This allows objtool to understand the control flow *around* the
retpoline, even if it can't yet follow what's inside.  This means the
ORC unwinder will fail to unwind from inside a retpoline, but will work
fine otherwise.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: thomas.lendacky@amd.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: https://lkml.kernel.org/r/1515707194-20531-3-git-send-email-dwmw@amazon.co.uk
6 years agoobjtool: Detect jumps to retpoline thunks
Josh Poimboeuf [Thu, 11 Jan 2018 21:46:23 +0000 (21:46 +0000)]
objtool: Detect jumps to retpoline thunks

A direct jump to a retpoline thunk is really an indirect jump in
disguise.  Change the objtool instruction type accordingly.

Objtool needs to know where indirect branches are so it can detect
switch statement jump tables.

This fixes a bunch of warnings with CONFIG_RETPOLINE like:

  arch/x86/events/intel/uncore_nhmex.o: warning: objtool: nhmex_rbox_msr_enable_event()+0x44: sibling call from callable instruction with modified stack frame
  kernel/signal.o: warning: objtool: copy_siginfo_to_user()+0x91: sibling call from callable instruction with modified stack frame
  ...

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: thomas.lendacky@amd.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: https://lkml.kernel.org/r/1515707194-20531-2-git-send-email-dwmw@amazon.co.uk
6 years agox86/pti: Make unpoison of pgd for trusted boot work for real
Dave Hansen [Wed, 10 Jan 2018 22:49:39 +0000 (14:49 -0800)]
x86/pti: Make unpoison of pgd for trusted boot work for real

The inital fix for trusted boot and PTI potentially misses the pgd clearing
if pud_alloc() sets a PGD.  It probably works in *practice* because for two
adjacent calls to map_tboot_page() that share a PGD entry, the first will
clear NX, *then* allocate and set the PGD (without NX clear).  The second
call will *not* allocate but will clear the NX bit.

Defer the NX clearing to a point after it is known that all top-level
allocations have occurred.  Add a comment to clarify why.

[ tglx: Massaged changelog ]

Fixes: 262b6b30087 ("x86/tboot: Unbreak tboot with PTI enabled")
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Jon Masters <jcm@redhat.com>
Cc: "Tim Chen" <tim.c.chen@linux.intel.com>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: peterz@infradead.org
Cc: ning.sun@intel.com
Cc: tboot-devel@lists.sourceforge.net
Cc: andi@firstfloor.org
Cc: luto@kernel.org
Cc: law@redhat.com
Cc: pbonzini@redhat.com
Cc: torvalds@linux-foundation.org
Cc: gregkh@linux-foundation.org
Cc: dwmw@amazon.co.uk
Cc: nickc@redhat.com
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180110224939.2695CD47@viggo.jf.intel.com
6 years agox86/PCI: Move and shrink AMD 64-bit window to avoid conflict
=?UTF-8?q?Christian=20K=C3=B6nig?= [Thu, 11 Jan 2018 13:23:30 +0000 (14:23 +0100)]
x86/PCI: Move and shrink AMD 64-bit window to avoid conflict

Avoid problems with BIOS implementations which don't report all used
resources to the OS by only allocating a 256GB window directly below the
hardware limit (from the BKDG, sec 2.4.6).

Fixes a silent reboot loop reported by Aaro Koskinen <aaro.koskinen@iki.fi>
on an AMD-based MSI MS-7699/760GA-P43(FX) system.  This was apparently
caused by RAM or other unreported hardware that conflicted with the new
window.

Link: https://support.amd.com/TechDocs/49125_15h_Models_30h-3Fh_BKDG.pdf
Link: https://lkml.kernel.org/r/20180105220412.fzpwqe4zljdawr36@darkstar.musicnaut.iki.fi
Fixes: fa564ad96366 ("x86/PCI: Enable a 64bit BAR on AMD Family 15h (Models 00-1f, 30-3f, 60-7f)")
Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Christian König <christian.koenig@amd.com>
[bhelgaas: changelog, comment, Fixes:]
Signed-off-by: Bjorn Helgaas <helgaas@kernel.org>
6 years agoDocumentation: usb: fix typo in UVC gadgetfs config command
Bin Liu [Tue, 9 Jan 2018 19:27:17 +0000 (13:27 -0600)]
Documentation: usb: fix typo in UVC gadgetfs config command

This seems to be a copy&paste error. With the fix the uvc gadget now can
be created by following the instrucitons.

Signed-off-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
6 years agousb: misc: usb3503: make sure reset is low for at least 100us
Stefan Agner [Thu, 11 Jan 2018 13:47:40 +0000 (14:47 +0100)]
usb: misc: usb3503: make sure reset is low for at least 100us

When using a GPIO which is high by default, and initialize the
driver in USB Hub mode, initialization fails with:
  [  111.757794] usb3503 0-0008: SP_ILOCK failed (-5)

The reason seems to be that the chip is not properly reset.
Probe does initialize reset low, however some lines later the
code already set it back high, which is not long enouth.

Make sure reset is asserted for at least 100us by inserting a
delay after initializing the reset pin during probe.

Signed-off-by: Stefan Agner <stefan@agner.ch>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
6 years agox86/PCI: Add "pci=big_root_window" option for AMD 64-bit windows
=?UTF-8?q?Christian=20K=C3=B6nig?= [Thu, 11 Jan 2018 13:23:29 +0000 (14:23 +0100)]
x86/PCI: Add "pci=big_root_window" option for AMD 64-bit windows

Only try to enable a 64-bit window on AMD CPUs when "pci=big_root_window"
is specified.

This taints the kernel because the new 64-bit window uses address space we
don't know anything about, and it may contain unreported devices or memory
that would conflict with the window.

The pci_amd_enable_64bit_bar() quirk that enables the window is specific to
AMD CPUs.  The generic solution would be to have the firmware enable the
window and describe it in the host bridge's _CRS method, or at least
describe it in the _PRS method so the OS would have the option of enabling
it.

Signed-off-by: Christian König <christian.koenig@amd.com>
[bhelgaas: changelog, extend doc, mention taint in dmesg]
Signed-off-by: Bjorn Helgaas <helgaas@kernel.org>
6 years agoMerge branch 'kvm-insert-lfence' into kvm-master
Paolo Bonzini [Thu, 11 Jan 2018 17:20:48 +0000 (18:20 +0100)]
Merge branch 'kvm-insert-lfence' into kvm-master

Topic branch for CVE-2017-5753, avoiding conflicts in the next merge window.

6 years agoKVM: x86: Add memory barrier on vmcs field lookup
Andrew Honig [Wed, 10 Jan 2018 18:12:03 +0000 (10:12 -0800)]
KVM: x86: Add memory barrier on vmcs field lookup

This adds a memory barrier when performing a lookup into
the vmcs_field_to_offset_table.  This is related to
CVE-2017-5753.

Signed-off-by: Andrew Honig <ahonig@google.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
6 years agoMerge tag 'usb-serial-4.15-rc8' of https://git.kernel.org/pub/scm/linux/kernel/git...
Greg Kroah-Hartman [Thu, 11 Jan 2018 16:40:16 +0000 (17:40 +0100)]
Merge tag 'usb-serial-4.15-rc8' of https://git./linux/kernel/git/johan/usb-serial into usb-linus

Johan writes:

USB-serial fixes for v4.15-rc8

Here are a couple of new device ids for cp210x.

Both have been in linux-next with no reported issues.

Signed-off-by: Johan Hovold <johan@kernel.org>
6 years agoKVM: x86: emulate #UD while in guest mode
Paolo Bonzini [Thu, 11 Jan 2018 15:55:24 +0000 (16:55 +0100)]
KVM: x86: emulate #UD while in guest mode

This reverts commits ae1f57670703656cc9f293722c3b8b6782f8ab3f
and ac9b305caa0df6f5b75d294e4b86c1027648991e.

If the hardware doesn't support MOVBE, but L0 sets CPUID.01H:ECX.MOVBE
in L1's emulated CPUID information, then L1 is likely to pass that
CPUID bit through to L2. L2 will expect MOVBE to work, but if L1
doesn't intercept #UD, then any MOVBE instruction executed in L2 will
raise #UD, and the exception will be delivered in L2.

Commit ac9b305caa0df6f5b75d294e4b86c1027648991e is a better and more
complete version of ae1f57670703 ("KVM: nVMX: Do not emulate #UD while
in guest mode"); however, neither considers the above case.

Suggested-by: Jim Mattson <jmattson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
6 years agox86: kvm: propagate register_shrinker return code
Arnd Bergmann [Wed, 10 Jan 2018 16:26:59 +0000 (17:26 +0100)]
x86: kvm: propagate register_shrinker return code

Patch "mm,vmscan: mark register_shrinker() as __must_check" is
queued for 4.16 in linux-mm and adds a warning about the unchecked
call to register_shrinker:

arch/x86/kvm/mmu.c:5485:2: warning: ignoring return value of 'register_shrinker', declared with attribute warn_unused_result [-Wunused-result]

This changes the kvm_mmu_module_init() function to fail itself
when the call to register_shrinker fails.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
6 years agoMerge tag 'kvm-ppc-fixes-4.15-3' of git://git.kernel.org/pub/scm/linux/kernel/git...
Paolo Bonzini [Thu, 11 Jan 2018 13:07:27 +0000 (14:07 +0100)]
Merge tag 'kvm-ppc-fixes-4.15-3' of git://git./linux/kernel/git/paulus/powerpc into kvm-master

PPC KVM fixes for 4.15

Four commits here, including two that were tagged but never merged.
Three of them are for the HPT resizing code; two of those fix a
user-triggerable use-after-free in the host, and one that fixes
stale TLB entries in the guest.  The remaining commit fixes a bug
causing PR KVM guests under PowerVM to fail to start.

6 years agoKVM MMU: check pending exception before injecting APF
Haozhong Zhang [Wed, 10 Jan 2018 13:44:42 +0000 (21:44 +0800)]
KVM MMU: check pending exception before injecting APF

For example, when two APF's for page ready happen after one exit and
the first one becomes pending, the second one will result in #DF.
Instead, just handle the second page fault synchronously.

Reported-by: Ross Zwisler <zwisler@gmail.com>
Message-ID: <CAOxpaSUBf8QoOZQ1p4KfUp0jq76OKfGY4Uxs-Gg8ngReD99xww@mail.gmail.com>
Reported-by: Alec Blayne <ab@tevsa.net>
Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
6 years agodrm/i915: Don't adjust priority on an already signaled fence
Chris Wilson [Sat, 6 Jan 2018 10:56:18 +0000 (10:56 +0000)]
drm/i915: Don't adjust priority on an already signaled fence

When we retire a signaled fence, we free the dependency tree. However,
we skip clearing the list so that if we then try to adjust the priority
of the signaled fence, we may walk the list of freed dependencies.

[ 3083.156757] ==================================================================
[ 3083.156806] BUG: KASAN: use-after-free in execlists_schedule+0x199/0x660 [i915]
[ 3083.156810] Read of size 8 at addr ffff8806bf20f400 by task Xorg/831

[ 3083.156815] CPU: 0 PID: 831 Comm: Xorg Not tainted 4.15.0-rc6-no-psn+ #1
[ 3083.156817] Hardware name: Notebook                         N24_25BU/N24_25BU, BIOS 5.12 02/17/2017
[ 3083.156818] Call Trace:
[ 3083.156823]  dump_stack+0x5c/0x7a
[ 3083.156827]  print_address_description+0x6b/0x290
[ 3083.156830]  kasan_report+0x28f/0x380
[ 3083.156872]  ? execlists_schedule+0x199/0x660 [i915]
[ 3083.156914]  execlists_schedule+0x199/0x660 [i915]
[ 3083.156956]  ? intel_crtc_atomic_check+0x146/0x4e0 [i915]
[ 3083.156997]  ? execlists_submit_request+0xe0/0xe0 [i915]
[ 3083.157038]  ? i915_vma_misplaced.part.4+0x25/0xb0 [i915]
[ 3083.157079]  ? __i915_vma_do_pin+0x7c8/0xc80 [i915]
[ 3083.157121]  ? intel_atomic_state_alloc+0x44/0x60 [i915]
[ 3083.157130]  ? drm_atomic_helper_page_flip+0x3e/0xb0 [drm_kms_helper]
[ 3083.157145]  ? drm_mode_page_flip_ioctl+0x7d2/0x850 [drm]
[ 3083.157159]  ? drm_ioctl_kernel+0xa7/0xf0 [drm]
[ 3083.157172]  ? drm_ioctl+0x45b/0x560 [drm]
[ 3083.157211]  i915_gem_object_wait_priority+0x14c/0x2c0 [i915]
[ 3083.157251]  ? i915_gem_get_aperture_ioctl+0x150/0x150 [i915]
[ 3083.157290]  ? i915_vma_pin_fence+0x1d8/0x320 [i915]
[ 3083.157331]  ? intel_pin_and_fence_fb_obj+0x175/0x250 [i915]
[ 3083.157372]  ? intel_rotation_info_size+0x60/0x60 [i915]
[ 3083.157413]  ? intel_link_compute_m_n+0x80/0x80 [i915]
[ 3083.157428]  ? drm_dev_printk+0x1b0/0x1b0 [drm]
[ 3083.157443]  ? drm_dev_printk+0x1b0/0x1b0 [drm]
[ 3083.157485]  intel_prepare_plane_fb+0x2f8/0x5a0 [i915]
[ 3083.157527]  ? intel_crtc_get_vblank_counter+0x80/0x80 [i915]
[ 3083.157536]  drm_atomic_helper_prepare_planes+0xa0/0x1c0 [drm_kms_helper]
[ 3083.157587]  intel_atomic_commit+0x12e/0x4e0 [i915]
[ 3083.157605]  drm_atomic_helper_page_flip+0xa2/0xb0 [drm_kms_helper]
[ 3083.157621]  drm_mode_page_flip_ioctl+0x7d2/0x850 [drm]
[ 3083.157638]  ? drm_mode_cursor2_ioctl+0x10/0x10 [drm]
[ 3083.157652]  ? drm_lease_owner+0x1a/0x30 [drm]
[ 3083.157668]  ? drm_mode_cursor2_ioctl+0x10/0x10 [drm]
[ 3083.157681]  drm_ioctl_kernel+0xa7/0xf0 [drm]
[ 3083.157696]  drm_ioctl+0x45b/0x560 [drm]
[ 3083.157711]  ? drm_mode_cursor2_ioctl+0x10/0x10 [drm]
[ 3083.157725]  ? drm_getstats+0x20/0x20 [drm]
[ 3083.157729]  ? timerqueue_del+0x49/0x80
[ 3083.157732]  ? __remove_hrtimer+0x62/0xb0
[ 3083.157735]  ? hrtimer_try_to_cancel+0x173/0x210
[ 3083.157738]  do_vfs_ioctl+0x13b/0x880
[ 3083.157741]  ? ioctl_preallocate+0x140/0x140
[ 3083.157744]  ? _raw_spin_unlock_irq+0xe/0x30
[ 3083.157746]  ? do_setitimer+0x234/0x370
[ 3083.157750]  ? SyS_setitimer+0x19e/0x1b0
[ 3083.157752]  ? SyS_alarm+0x140/0x140
[ 3083.157755]  ? __rcu_read_unlock+0x66/0x80
[ 3083.157757]  ? __fget+0xc4/0x100
[ 3083.157760]  SyS_ioctl+0x74/0x80
[ 3083.157763]  entry_SYSCALL_64_fastpath+0x1a/0x7d
[ 3083.157765] RIP: 0033:0x7f6135d0c6a7
[ 3083.157767] RSP: 002b:00007fff01451888 EFLAGS: 00003246 ORIG_RAX: 0000000000000010
[ 3083.157769] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f6135d0c6a7
[ 3083.157771] RDX: 00007fff01451950 RSI: 00000000c01864b0 RDI: 000000000000000c
[ 3083.157772] RBP: 00007f613076f600 R08: 0000000000000001 R09: 0000000000000000
[ 3083.157773] R10: 0000000000000060 R11: 0000000000003246 R12: 0000000000000000
[ 3083.157774] R13: 0000000000000060 R14: 000000000000001b R15: 0000000000000060

[ 3083.157779] Allocated by task 831:
[ 3083.157783]  kmem_cache_alloc+0xc0/0x200
[ 3083.157822]  i915_gem_request_await_dma_fence+0x2c4/0x5d0 [i915]
[ 3083.157861]  i915_gem_request_await_object+0x321/0x370 [i915]
[ 3083.157900]  i915_gem_do_execbuffer+0x1165/0x19c0 [i915]
[ 3083.157937]  i915_gem_execbuffer2+0x1ad/0x550 [i915]
[ 3083.157950]  drm_ioctl_kernel+0xa7/0xf0 [drm]
[ 3083.157962]  drm_ioctl+0x45b/0x560 [drm]
[ 3083.157964]  do_vfs_ioctl+0x13b/0x880
[ 3083.157966]  SyS_ioctl+0x74/0x80
[ 3083.157968]  entry_SYSCALL_64_fastpath+0x1a/0x7d

[ 3083.157971] Freed by task 831:
[ 3083.157973]  kmem_cache_free+0x77/0x220
[ 3083.158012]  i915_gem_request_retire+0x72c/0xa70 [i915]
[ 3083.158051]  i915_gem_request_alloc+0x1e9/0x8b0 [i915]
[ 3083.158089]  i915_gem_do_execbuffer+0xa96/0x19c0 [i915]
[ 3083.158127]  i915_gem_execbuffer2+0x1ad/0x550 [i915]
[ 3083.158140]  drm_ioctl_kernel+0xa7/0xf0 [drm]
[ 3083.158153]  drm_ioctl+0x45b/0x560 [drm]
[ 3083.158155]  do_vfs_ioctl+0x13b/0x880
[ 3083.158156]  SyS_ioctl+0x74/0x80
[ 3083.158158]  entry_SYSCALL_64_fastpath+0x1a/0x7d

[ 3083.158162] The buggy address belongs to the object at ffff8806bf20f400
                which belongs to the cache i915_dependency of size 64
[ 3083.158166] The buggy address is located 0 bytes inside of
                64-byte region [ffff8806bf20f400ffff8806bf20f440)
[ 3083.158168] The buggy address belongs to the page:
[ 3083.158171] page:00000000d43decc4 count:1 mapcount:0 mapping:          (null) index:0x0
[ 3083.158174] flags: 0x17ffe0000000100(slab)
[ 3083.158179] raw: 017ffe0000000100 0000000000000000 0000000000000000 0000000180200020
[ 3083.158182] raw: ffffea001afc16c0 0000000500000005 ffff880731b881c0 0000000000000000
[ 3083.158184] page dumped because: kasan: bad access detected

[ 3083.158187] Memory state around the buggy address:
[ 3083.158190]  ffff8806bf20f300: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
[ 3083.158192]  ffff8806bf20f380: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
[ 3083.158195] >ffff8806bf20f400: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
[ 3083.158196]                    ^
[ 3083.158199]  ffff8806bf20f480: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
[ 3083.158201]  ffff8806bf20f500: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
[ 3083.158203] ==================================================================

Reported-by: Alexandru Chirvasitu <achirvasub@gmail.com>
Reported-by: Mike Keehan <mike@keehan.net>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=104436
Fixes: 1f181225f8ec ("drm/i915/execlists: Keep request->priority for its lifetime")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Alexandru Chirvasitu <achirvasub@gmail.com>
Cc: Michał Winiarski <michal.winiarski@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Tested-by: Alexandru Chirvasitu <achirvasub@gmail.com>
Reviewed-by: Michał Winiarski <michal.winiarski@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180106105618.13532-1-chris@chris-wilson.co.uk
(cherry picked from commit c218ee03b9315073ce43992792554dafa0626eb8)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
6 years agodrm/i915: Whitelist SLICE_COMMON_ECO_CHICKEN1 on Geminilake.
Kenneth Graunke [Fri, 5 Jan 2018 08:59:05 +0000 (00:59 -0800)]
drm/i915: Whitelist SLICE_COMMON_ECO_CHICKEN1 on Geminilake.

Geminilake requires the 3D driver to select whether barriers are
intended for compute shaders, or tessellation control shaders, by
whacking a "Barrier Mode" bit in SLICE_COMMON_ECO_CHICKEN1 when
switching pipelines.  Failure to do this properly can result in GPU
hangs.

Unfortunately, this means it needs to switch mid-batch, so only
userspace can properly set it.  To facilitate this, the kernel needs
to whitelist the register.

The workarounds page currently tags this as applying to Broxton only,
but that doesn't make sense.  The documentation for the register it
references says the bit userspace is supposed to toggle only exists on
Geminilake.  Empirically, the Mesa patch to toggle this bit appears to
fix intermittent GPU hangs in tessellation control shader barrier tests
on Geminilake; we haven't seen those hangs on Broxton.

v2: Mention WA #0862 in the comment (it doesn't have a name).

Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Acked-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180105085905.9298-1-kenneth@whitecape.org
(cherry picked from commit ab062639edb0412daf6de540725276b9a5d217f9)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
6 years agoMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Linus Torvalds [Thu, 11 Jan 2018 01:55:42 +0000 (17:55 -0800)]
Merge branch 'for-linus' of git://git./linux/kernel/git/viro/vfs

Pull vfs regression fix from Al Viro/

Fix a leak in socket() introduced by commit 8e1611e23579 ("make
sock_alloc_file() do sock_release() on failures").

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  Fix a leak in socket(2) when we fail to allocate a file descriptor.

6 years agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Linus Torvalds [Thu, 11 Jan 2018 01:53:18 +0000 (17:53 -0800)]
Merge git://git./linux/kernel/git/davem/net

Pull networking fixes from David Miller:

 1) BPF speculation prevention and BPF_JIT_ALWAYS_ON, from Alexei
    Starovoitov.

 2) Revert dev_get_random_name() changes as adjust the error code
    returns seen by userspace definitely breaks stuff.

 3) Fix TX DMA map/unmap on older iwlwifi devices, from Emmanuel
    Grumbach.

 4) From wrong AF family when requesting sock diag modules, from Andrii
    Vladyka.

 5) Don't add new ipv6 routes attached to the null_entry, from Wei Wang.

 6) Some SCTP sockopt length fixes from Marcelo Ricardo Leitner.

 7) Don't leak when removing VLAN ID 0, from Cong Wang.

 8) Hey there's a potential leak in ipv6_make_skb() too, from Eric
    Dumazet.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (27 commits)
  ipv6: sr: fix TLVs not being copied using setsockopt
  ipv6: fix possible mem leaks in ipv6_make_skb()
  mlxsw: spectrum_qdisc: Don't use variable array in mlxsw_sp_tclass_congestion_enable
  mlxsw: pci: Wait after reset before accessing HW
  nfp: always unmask aux interrupts at init
  8021q: fix a memory leak for VLAN 0 device
  of_mdio: avoid MDIO bus removal when a PHY is missing
  caif_usb: use strlcpy() instead of strncpy()
  doc: clarification about setting SO_ZEROCOPY
  net: gianfar_ptp: move set_fipers() to spinlock protecting area
  sctp: make use of pre-calculated len
  sctp: add a ceiling to optlen in some sockopts
  sctp: GFP_ATOMIC is not needed in sctp_setsockopt_events
  bpf: introduce BPF_JIT_ALWAYS_ON config
  bpf: avoid false sharing of map refcount with max_entries
  ipv6: remove null_entry before adding default route
  SolutionEngine771x: add Ether TSU resource
  SolutionEngine771x: fix Ether platform data
  docs-rst: networking: wire up msg_zerocopy
  net: ipv4: emulate READ_ONCE() on ->hdrincl bit-field in raw_sendmsg()
  ...

6 years agoFix a leak in socket(2) when we fail to allocate a file descriptor.
Al Viro [Wed, 10 Jan 2018 23:47:05 +0000 (18:47 -0500)]
Fix a leak in socket(2) when we fail to allocate a file descriptor.

Got broken by "make sock_alloc_file() do sock_release() on failures" -
cleanup after sock_map_fd() failure got pulled all the way into
sock_alloc_file(), but it used to serve the case when sock_map_fd()
failed *before* getting to sock_alloc_file() as well, and that got
lost.  Trivial to fix, fortunately.

Fixes: 8e1611e23579 (make sock_alloc_file() do sock_release() on failures)
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
6 years agoipv6: sr: fix TLVs not being copied using setsockopt
Mathieu Xhonneux [Wed, 10 Jan 2018 13:35:49 +0000 (13:35 +0000)]
ipv6: sr: fix TLVs not being copied using setsockopt

Function ipv6_push_rthdr4 allows to add an IPv6 Segment Routing Header
to a socket through setsockopt, but the current implementation doesn't
copy possible TLVs at the end of the SRH received from userspace.

Therefore, the execution of the following branch if (sr_has_hmac(sr_phdr))
{ ... } will never complete since the len and type fields of a possible
HMAC TLV are not copied, hence seg6_get_tlv_hmac will return an error,
and the HMAC will not be computed.

This commit adds a memcpy in case TLVs have been appended to the SRH.

Fixes: a149e7c7ce81 ("ipv6: sr: add support for SRH injection through setsockopt")
Acked-by: David Lebrun <dlebrun@google.com>
Signed-off-by: Mathieu Xhonneux <m.xhonneux@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agoipv6: fix possible mem leaks in ipv6_make_skb()
Eric Dumazet [Wed, 10 Jan 2018 11:45:49 +0000 (03:45 -0800)]
ipv6: fix possible mem leaks in ipv6_make_skb()

ip6_setup_cork() might return an error, while memory allocations have
been done and must be rolled back.

Fixes: 6422398c2ab0 ("ipv6: introduce ipv6_make_skb")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Vlad Yasevich <vyasevich@gmail.com>
Reported-by: Mike Maloney <maloney@google.com>
Acked-by: Mike Maloney <maloney@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agoMerge branch 'mlxsw-couple-of-fixes'
David S. Miller [Wed, 10 Jan 2018 20:58:23 +0000 (15:58 -0500)]
Merge branch 'mlxsw-couple-of-fixes'

Jiri Pirko says:

====================
mlxsw: couple of fixes

Couple of small fixes for mlxsw driver.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agomlxsw: spectrum_qdisc: Don't use variable array in mlxsw_sp_tclass_congestion_enable
Jiri Pirko [Wed, 10 Jan 2018 10:42:44 +0000 (11:42 +0100)]
mlxsw: spectrum_qdisc: Don't use variable array in mlxsw_sp_tclass_congestion_enable

Resolve the sparse warning:
"sparse: Variable length array is used."
Use 2 arrays for 2 PRM register accesses.

Fixes: 96f17e0776c2 ("mlxsw: spectrum: Support RED qdisc offload")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Yuval Mintz <yuvalm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agomlxsw: pci: Wait after reset before accessing HW
Yuval Mintz [Wed, 10 Jan 2018 10:42:43 +0000 (11:42 +0100)]
mlxsw: pci: Wait after reset before accessing HW

After performing reset driver polls on HW indication until learning
that the reset is done, but immediately after reset the device becomes
unresponsive which might lead to completion timeout on the first read.

Wait for 100ms before starting the polling.

Fixes: 233fa44bd67a ("mlxsw: pci: Implement reset done check")
Signed-off-by: Yuval Mintz <yuvalm@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agonfp: always unmask aux interrupts at init
Jakub Kicinski [Wed, 10 Jan 2018 02:14:28 +0000 (18:14 -0800)]
nfp: always unmask aux interrupts at init

The link state and exception interrupts may be masked when we probe.
The firmware should in theory prevent sending (and automasking) those
interrupts if the device is disabled, but if my reading of the FW code
is correct there are firmwares out there with race conditions in this
area.  The interrupt may also be masked if previous driver which used
the device was malfunctioning and we didn't load the FW (there is no
other good way to comprehensively reset the PF).

Note that FW unmasks the data interrupts by itself when vNIC is
enabled, such helpful operation is not performed for LSC/EXN interrupts.

Always unmask the auxiliary interrupts after request_irq().  On the
remove path add missing PCI write flush before free_irq().

Fixes: 4c3523623dc0 ("net: add driver for Netronome NFP4000/NFP6000 NIC VFs")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Dirk van der Merwe <dirk.vandermerwe@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years ago8021q: fix a memory leak for VLAN 0 device
Cong Wang [Tue, 9 Jan 2018 21:40:41 +0000 (13:40 -0800)]
8021q: fix a memory leak for VLAN 0 device

A vlan device with vid 0 is allow to creat by not able to be fully
cleaned up by unregister_vlan_dev() which checks for vlan_id!=0.

Also, VLAN 0 is probably not a valid number and it is kinda
"reserved" for HW accelerating devices, but it is probably too
late to reject it from creation even if makes sense. Instead,
just remove the check in unregister_vlan_dev().

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Fixes: ad1afb003939 ("vlan_dev: VLAN 0 should be treated as "no vlan tag" (802.1p packet)")
Cc: Vlad Yasevich <vyasevich@gmail.com>
Cc: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agoMerge tag 'wireless-drivers-for-davem-2018-01-09' of git://git.kernel.org/pub/scm...
David S. Miller [Wed, 10 Jan 2018 20:08:46 +0000 (15:08 -0500)]
Merge tag 'wireless-drivers-for-davem-2018-01-09' of git://git./linux/kernel/git/kvalo/wireless-drivers

Kalle Valo says:

====================
wireless-drivers fixes for 4.15

Hopefully the last set of fixes for 4.15.

iwlwifi

* fix DMA mapping regression since v4.14

wcn36xx

* fix dynamic power save which has been broken since the driver was commited
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agoof_mdio: avoid MDIO bus removal when a PHY is missing
Madalin Bucur [Tue, 9 Jan 2018 12:43:34 +0000 (14:43 +0200)]
of_mdio: avoid MDIO bus removal when a PHY is missing

If one of the child devices is missing the of_mdiobus_register_phy()
call will return -ENODEV. When a missing device is encountered the
registration of the remaining PHYs is stopped and the MDIO bus will
fail to register. Propagate all errors except ENODEV to avoid it.

Signed-off-by: Madalin Bucur <madalin.bucur@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agocaif_usb: use strlcpy() instead of strncpy()
Xiongfeng Wang [Tue, 9 Jan 2018 11:58:18 +0000 (19:58 +0800)]
caif_usb: use strlcpy() instead of strncpy()

gcc-8 reports

net/caif/caif_usb.c: In function 'cfusbl_device_notify':
./include/linux/string.h:245:9: warning: '__builtin_strncpy' output may
be truncated copying 15 bytes from a string of length 15
[-Wstringop-truncation]

The compiler require that the input param 'len' of strncpy() should be
greater than the length of the src string, so that '\0' is copied as
well. We can just use strlcpy() to avoid this warning.

Signed-off-by: Xiongfeng Wang <xiongfeng.wang@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agodoc: clarification about setting SO_ZEROCOPY
Kornilios Kourtis [Tue, 9 Jan 2018 08:52:22 +0000 (09:52 +0100)]
doc: clarification about setting SO_ZEROCOPY

Signed-off-by: Kornilios Kourtis <kou@zurich.ibm.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agonet: gianfar_ptp: move set_fipers() to spinlock protecting area
Yangbo Lu [Tue, 9 Jan 2018 03:02:33 +0000 (11:02 +0800)]
net: gianfar_ptp: move set_fipers() to spinlock protecting area

set_fipers() calling should be protected by spinlock in
case that any interrupt breaks related registers setting
and the function we expect. This patch is to move set_fipers()
to spinlock protecting area in ptp_gianfar_adjtime().

Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agoMerge branch 'sctp-Some-sockopt-optlen-fixes'
David S. Miller [Wed, 10 Jan 2018 19:53:23 +0000 (14:53 -0500)]
Merge branch 'sctp-Some-sockopt-optlen-fixes'

Marcelo Ricardo Leitner says:

====================
sctp: Some sockopt optlen fixes

Hangbin Liu reported that some SCTP sockopt are allowing the user to get
the kernel to allocate really large buffers by not having a ceiling on
optlen.

This patchset address this issue (in patch 2), replace an GFP_ATOMIC
that isn't needed and avoid calculating the option size multiple times
in some setsockopt.
====================

Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agosctp: make use of pre-calculated len
Marcelo Ricardo Leitner [Mon, 8 Jan 2018 21:02:29 +0000 (19:02 -0200)]
sctp: make use of pre-calculated len

Some sockopt handling functions were calculating the length of the
buffer to be written to userspace and then calculating it again when
actually writing the buffer, which could lead to some write not using
an up-to-date length.

This patch updates such places to just make use of the len variable.

Also, replace some sizeof(type) to sizeof(var).

Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agosctp: add a ceiling to optlen in some sockopts
Marcelo Ricardo Leitner [Mon, 8 Jan 2018 21:02:28 +0000 (19:02 -0200)]
sctp: add a ceiling to optlen in some sockopts

Hangbin Liu reported that some sockopt calls could cause the kernel to log
a warning on memory allocation failure if the user supplied a large optlen
value. That is because some of them called memdup_user() without a ceiling
on optlen, allowing it to try to allocate really large buffers.

This patch adds a ceiling by limiting optlen to the maximum allowed that
would still make sense for these sockopt.

Reported-by: Hangbin Liu <haliu@redhat.com>
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agosctp: GFP_ATOMIC is not needed in sctp_setsockopt_events
Marcelo Ricardo Leitner [Mon, 8 Jan 2018 21:02:27 +0000 (19:02 -0200)]
sctp: GFP_ATOMIC is not needed in sctp_setsockopt_events

So replace it with GFP_USER and also add __GFP_NOWARN.

Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agoMerge tag 'sound-4.15-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai...
Linus Torvalds [Wed, 10 Jan 2018 19:18:31 +0000 (11:18 -0800)]
Merge tag 'sound-4.15-rc8' of git://git./linux/kernel/git/tiwai/sound

Pull sound fixes from Takashi Iwai:
 "A collection of the last-minute small PCM fixes:

   - A workaround for the recent regression wrt PulseAudio

   - Removal of spurious WARN_ON() that is triggered by syzkaller

   - Fixes for aloop, hardening racy accesses

   - Fixes in PCM OSS emulation wrt the unabortable loops that may cause
     RCU stall"

* tag 'sound-4.15-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: pcm: Allow aborting mutex lock at OSS read/write loops
  ALSA: pcm: Abort properly at pending signal in OSS read/write loops
  ALSA: aloop: Fix racy hw constraints adjustment
  ALSA: aloop: Fix inconsistent format due to incomplete rule
  ALSA: aloop: Release cable upon open error path
  ALSA: pcm: Workaround for weird PulseAudio behavior on rewind error
  ALSA: pcm: Add missing error checks in OSS emulation plugin builder
  ALSA: pcm: Remove incorrect snd_BUG_ON() usages

6 years agox86/alternatives: Fix optimize_nops() checking
Borislav Petkov [Wed, 10 Jan 2018 11:28:16 +0000 (12:28 +0100)]
x86/alternatives: Fix optimize_nops() checking

The alternatives code checks only the first byte whether it is a NOP, but
with NOPs in front of the payload and having actual instructions after it
breaks the "optimized' test.

Make sure to scan all bytes before deciding to optimize the NOPs in there.

Reported-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Andrew Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: https://lkml.kernel.org/r/20180110112815.mgciyf5acwacphkq@pd.tnic
6 years agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
David S. Miller [Wed, 10 Jan 2018 16:17:21 +0000 (11:17 -0500)]
Merge git://git./pub/scm/linux/kernel/git/bpf/bpf

Daniel Borkmann says:

====================
pull-request: bpf 2018-01-09

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) Prevent out-of-bounds speculation in BPF maps by masking the
   index after bounds checks in order to fix spectre v1, and
   add an option BPF_JIT_ALWAYS_ON into Kconfig that allows for
   removing the BPF interpreter from the kernel in favor of
   JIT-only mode to make spectre v2 harder, from Alexei.

2) Remove false sharing of map refcount with max_entries which
   was used in spectre v1, from Daniel.

3) Add a missing NULL psock check in sockmap in order to fix
   a race, from John.

4) Fix test_align BPF selftest case since a recent change in
   verifier rejects the bit-wise arithmetic on pointers
   earlier but test_align update was missing, from Alexei.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agodrm/vmwgfx: Potential off by one in vmw_view_add()
Dan Carpenter [Wed, 10 Jan 2018 09:40:04 +0000 (12:40 +0300)]
drm/vmwgfx: Potential off by one in vmw_view_add()

The vmw_view_cmd_to_type() function returns vmw_view_max (3) on error.
It's one element beyond the end of the vmw_view_cotables[] table.

My read on this is that it's possible to hit this failure.  header->id
comes from vmw_cmd_check() and it's a user controlled number between
1040 and 1225 so we can hit that error.  But I don't have the hardware
to test this code.

Fixes: d80efd5cb3de ("drm/vmwgfx: Initial DX support")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Cc: <stable@vger.kernel.org>
6 years agoxen/gntdev: Fix partial gntdev_mmap() cleanup
Ross Lagerwall [Tue, 9 Jan 2018 12:10:22 +0000 (12:10 +0000)]
xen/gntdev: Fix partial gntdev_mmap() cleanup

When cleaning up after a partially successful gntdev_mmap(), unmap the
successfully mapped grant pages otherwise Xen will kill the domain if
in debug mode (Attempt to implicitly unmap a granted PTE) or Linux will
kill the process and emit "BUG: Bad page map in process" if Xen is in
release mode.

This is only needed when use_ptemod is true because gntdev_put_map()
will unmap grant pages itself when use_ptemod is false.

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
6 years agoxen/gntdev: Fix off-by-one error when unmapping with holes
Ross Lagerwall [Tue, 9 Jan 2018 12:10:21 +0000 (12:10 +0000)]
xen/gntdev: Fix off-by-one error when unmapping with holes

If the requested range has a hole, the calculation of the number of
pages to unmap is off by one. Fix it.

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
6 years agogpio: Add missing open drain/source handling to gpiod_set_value_cansleep()
Geert Uytterhoeven [Tue, 9 Jan 2018 18:08:21 +0000 (19:08 +0100)]
gpio: Add missing open drain/source handling to gpiod_set_value_cansleep()

Since commit f11a04464ae57e8d ("i2c: gpio: Enable working over slow
can_sleep GPIOs"), probing the i2c RTC connected to an i2c-gpio bus on
r8a7740/armadillo fails with:

    rtc-s35390a 0-0030: error resetting chip
    rtc-s35390a: probe of 0-0030 failed with error -5

More debug code reveals:

    i2c i2c-0: master_xfer[0] R, addr=0x30, len=1
    i2c i2c-0: NAK from device addr 0x30 msg #0
    s35390a_get_reg: ret = -6

Commit 02e479808b5d62f8 ("gpio: Alter semantics of *raw* operations to
actually be raw") moved open drain/source handling from
gpiod_set_raw_value_commit() to gpiod_set_value(), but forgot to take
into account that gpiod_set_value_cansleep() also needs this handling.
The i2c protocol mandates that i2c signals are open drain, hence i2c
communication fails.

Fix this by adding the missing handling to gpiod_set_value_cansleep(),
using a new common helper gpiod_set_value_nocheck().

Fixes: 02e479808b5d62f8 ("gpio: Alter semantics of *raw* operations to actually be raw")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
[removed underscore syntax, added kerneldoc]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
6 years agodrm/tegra: sor: Fix hang on Tegra124 eDP
Thierry Reding [Wed, 10 Jan 2018 12:04:58 +0000 (13:04 +0100)]
drm/tegra: sor: Fix hang on Tegra124 eDP

The SOR0 found on Tegra124 and Tegra210 only supports eDP and LVDS and
therefore has a slightly different clock tree than the SOR1 which does
not support eDP, but HDMI and DP instead.

Commit e1335e2f0cfc ("drm/tegra: sor: Reimplement pad clock") breaks
setups with eDP because the sor->clk_out clock is uninitialized and
therefore setting the parent clock (either the safe clock or either of
the display PLLs) fails, which can cause hangs later on since there is
no clock driving the module.

Fix this by falling back to the module clock for sor->clk_out on those
setups. This guarantees that the module will always be clocked by an
enabled clock and hence prevents those hangs.

Fixes: e1335e2f0cfc ("drm/tegra: sor: Reimplement pad clock")
Reported-by: Guillaume Tucker <guillaume.tucker@collabora.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
6 years agoKVM: PPC: Book3S HV: Always flush TLB in kvmppc_alloc_reset_hpt()
David Gibson [Wed, 10 Jan 2018 06:04:39 +0000 (17:04 +1100)]
KVM: PPC: Book3S HV: Always flush TLB in kvmppc_alloc_reset_hpt()

The KVM_PPC_ALLOCATE_HTAB ioctl(), implemented by kvmppc_alloc_reset_hpt()
is supposed to completely clear and reset a guest's Hashed Page Table (HPT)
allocating or re-allocating it if necessary.

In the case where an HPT of the right size already exists and it just
zeroes it, it forces a TLB flush on all guest CPUs, to remove any stale TLB
entries loaded from the old HPT.

However, that situation can arise when the HPT is resizing as well - or
even when switching from an RPT to HPT - so those cases need a TLB flush as
well.

So, move the TLB flush to trigger in all cases except for errors.

Cc: stable@vger.kernel.org # v4.10+
Fixes: f98a8bf9ee20 ("KVM: PPC: Book3S HV: Allow KVM_PPC_ALLOCATE_HTAB ioctl() to change HPT size")
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
6 years agoKVM: PPC: Book3S PR: Fix WIMG handling under pHyp
Alexey Kardashevskiy [Wed, 22 Nov 2017 03:42:21 +0000 (14:42 +1100)]
KVM: PPC: Book3S PR: Fix WIMG handling under pHyp

Commit 96df226 ("KVM: PPC: Book3S PR: Preserve storage control bits")
added code to preserve WIMG bits but it missed 2 special cases:
- a magic page in kvmppc_mmu_book3s_64_xlate() and
- guest real mode in kvmppc_handle_pagefault().

For these ptes, WIMG was 0 and pHyp failed on these causing a guest to
stop in the very beginning at NIP=0x100 (due to bd9166ffe "KVM: PPC:
Book3S PR: Exit KVM on failed mapping").

According to LoPAPR v1.1 14.5.4.1.2 H_ENTER:

 The hypervisor checks that the WIMG bits within the PTE are appropriate
 for the physical page number else H_Parameter return. (For System Memory
 pages WIMG=0010, or, 1110 if the SAO option is enabled, and for IO pages
 WIMG=01**.)

This hence initializes WIMG to non-zero value HPTE_R_M (0x10), as expected
by pHyp.

[paulus@ozlabs.org - fix compile for 32-bit]

Cc: stable@vger.kernel.org # v4.11+
Fixes: 96df226 "KVM: PPC: Book3S PR: Preserve storage control bits"
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Tested-by: Ruediger Oertel <ro@suse.de>
Reviewed-by: Greg Kurz <groug@kaod.org>
Tested-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
6 years agomembarrier: Disable preemption when calling smp_call_function_many()
Mathieu Desnoyers [Fri, 15 Dec 2017 19:23:10 +0000 (14:23 -0500)]
membarrier: Disable preemption when calling smp_call_function_many()

smp_call_function_many() requires disabling preemption around the call.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: <stable@vger.kernel.org> # v4.14+
Cc: Andrea Parri <parri.andrea@gmail.com>
Cc: Andrew Hunter <ahh@google.com>
Cc: Avi Kivity <avi@scylladb.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Dave Watson <davejwatson@fb.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maged Michael <maged.michael@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20171215192310.25293-1-mathieu.desnoyers@efficios.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
6 years agoMerge tag 'riscv-for-linus-4.15-rc8_cleanups' of git://git.kernel.org/pub/scm/linux...
Linus Torvalds [Tue, 9 Jan 2018 23:45:06 +0000 (15:45 -0800)]
Merge tag 'riscv-for-linus-4.15-rc8_cleanups' of git://git./linux/kernel/git/palmer/linux

Pull RISC-V updates from Palmer Dabbelt:
 "This contains what I hope are the last RISC-V changes to go into 4.15.
  I know it's a bit last minute, but I think they're all fairly small
  changes:

   - SR_* constants have been renamed to match the latest ISA
     specification.

   - Some CONFIG_MMU #ifdef cruft has been removed. We've never
     supported !CONFIG_MMU.

   - __NR_riscv_flush_icache is now visible to userspace. We were hoping
     to avoid making this public in order to force userspace to call the
     vDSO entry, but it looks like QEMU's user-mode emulation doesn't
     want to emulate a vDSO. In order to allow glibc to fall back to a
     system call when the vDSO entry doesn't exist we're just

   - Our defconfig is no long empty. This is another one that just
     slipped through the cracks. The defconfig isn't perfect, but it's
     at least close to what users will want for the first RISC-V
     development board. Getting closer is kind of splitting hairs here:
     none of the RISC-V specific drivers are in yet, so it's not like
     things will boot out of the box.

  The only one that's strictly necessary is the __NR_riscv_flush_icache
  change, as I want that to be part of the public API starting from our
  first kernel so nobody has to worry about it. The others are nice to
  haves, but they seem sane for 4.15 to me"

* tag 'riscv-for-linus-4.15-rc8_cleanups' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/linux:
  riscv: rename SR_* constants to match the spec
  riscv: remove CONFIG_MMU ifdefs
  RISC-V: Make __NR_riscv_flush_icache visible to userspace
  RISC-V: Add a basic defconfig

6 years agoMerge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Linus Torvalds [Tue, 9 Jan 2018 23:43:13 +0000 (15:43 -0800)]
Merge branch 'upstream' of git://git.linux-mips.org/ralf/upstream-linus

Pull MIPS fixes from Ralf Baechle:
 "Another round of MIPS fixes for 4.15.

   - Maciej Rozycki found another series of FP issues which requires a
     seven part series to restructure and fix.

   - James fixes a warning about .set mt which gas doesn't like when
     building for R1 processors"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: Validate PR_SET_FP_MODE prctl(2) requests against the ABI of the task
  MIPS: Disallow outsized PTRACE_SETREGSET NT_PRFPREG regset accesses
  MIPS: Also verify sizeof `elf_fpreg_t' with PTRACE_SETREGSET
  MIPS: Fix an FCSR access API regression with NT_PRFPREG and MSA
  MIPS: Consistently handle buffer counter with PTRACE_SETREGSET
  MIPS: Guard against any partial write attempt with PTRACE_SETREGSET
  MIPS: Factor out NT_PRFPREG regset access helpers
  MIPS: CPS: Fix r1 .set mt assembler warning

6 years agobpf: introduce BPF_JIT_ALWAYS_ON config
Alexei Starovoitov [Tue, 9 Jan 2018 18:04:29 +0000 (10:04 -0800)]
bpf: introduce BPF_JIT_ALWAYS_ON config

The BPF interpreter has been used as part of the spectre 2 attack CVE-2017-5715.

A quote from goolge project zero blog:
"At this point, it would normally be necessary to locate gadgets in
the host kernel code that can be used to actually leak data by reading
from an attacker-controlled location, shifting and masking the result
appropriately and then using the result of that as offset to an
attacker-controlled address for a load. But piecing gadgets together
and figuring out which ones work in a speculation context seems annoying.
So instead, we decided to use the eBPF interpreter, which is built into
the host kernel - while there is no legitimate way to invoke it from inside
a VM, the presence of the code in the host kernel's text section is sufficient
to make it usable for the attack, just like with ordinary ROP gadgets."

To make attacker job harder introduce BPF_JIT_ALWAYS_ON config
option that removes interpreter from the kernel in favor of JIT-only mode.
So far eBPF JIT is supported by:
x64, arm64, arm32, sparc64, s390, powerpc64, mips64

The start of JITed program is randomized and code page is marked as read-only.
In addition "constant blinding" can be turned on with net.core.bpf_jit_harden

v2->v3:
- move __bpf_prog_ret0 under ifdef (Daniel)

v1->v2:
- fix init order, test_bpf and cBPF (Daniel's feedback)
- fix offloaded bpf (Jakub's feedback)
- add 'return 0' dummy in case something can invoke prog->bpf_func
- retarget bpf tree. For bpf-next the patch would need one extra hunk.
  It will be sent when the trees are merged back to net-next

Considered doing:
  int bpf_jit_enable __read_mostly = BPF_EBPF_JIT_DEFAULT;
but it seems better to land the patch as-is and in bpf-next remove
bpf_jit_enable global variable from all JITs, consolidate in one place
and remove this jit_init() function.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
6 years agoMerge branch 'for-linus' of git://git.kernel.dk/linux-block
Linus Torvalds [Tue, 9 Jan 2018 19:20:55 +0000 (11:20 -0800)]
Merge branch 'for-linus' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "A set of fixes that should go into this release. This contains:

   - An NVMe pull request from Christoph, with a few critical fixes for
     NVMe.

   - A block drain queue fix from Ming.

   - The concurrent lo_open/release fix for loop"

* 'for-linus' of git://git.kernel.dk/linux-block:
  loop: fix concurrent lo_open/lo_release
  block: drain queue before waiting for q_usage_counter becoming zero
  nvme-fcloop: avoid possible uninitialized variable warning
  nvme-mpath: fix last path removal during traffic
  nvme-rdma: fix concurrent reset and reconnect
  nvme: fix sector units when going between formats
  nvme-pci: move use_sgl initialization to nvme_init_iod()

6 years agobpf: avoid false sharing of map refcount with max_entries
Daniel Borkmann [Tue, 9 Jan 2018 12:17:44 +0000 (13:17 +0100)]
bpf: avoid false sharing of map refcount with max_entries

In addition to commit b2157399cc98 ("bpf: prevent out-of-bounds
speculation") also change the layout of struct bpf_map such that
false sharing of fast-path members like max_entries is avoided
when the maps reference counter is altered. Therefore enforce
them to be placed into separate cachelines.

pahole dump after change:

  struct bpf_map {
        const struct bpf_map_ops  * ops;                 /*     0     8 */
        struct bpf_map *           inner_map_meta;       /*     8     8 */
        void *                     security;             /*    16     8 */
        enum bpf_map_type          map_type;             /*    24     4 */
        u32                        key_size;             /*    28     4 */
        u32                        value_size;           /*    32     4 */
        u32                        max_entries;          /*    36     4 */
        u32                        map_flags;            /*    40     4 */
        u32                        pages;                /*    44     4 */
        u32                        id;                   /*    48     4 */
        int                        numa_node;            /*    52     4 */
        bool                       unpriv_array;         /*    56     1 */

        /* XXX 7 bytes hole, try to pack */

        /* --- cacheline 1 boundary (64 bytes) --- */
        struct user_struct *       user;                 /*    64     8 */
        atomic_t                   refcnt;               /*    72     4 */
        atomic_t                   usercnt;              /*    76     4 */
        struct work_struct         work;                 /*    80    32 */
        char                       name[16];             /*   112    16 */
        /* --- cacheline 2 boundary (128 bytes) --- */

        /* size: 128, cachelines: 2, members: 17 */
        /* sum members: 121, holes: 1, sum holes: 7 */
  };

Now all entries in the first cacheline are read only throughout
the life time of the map, set up once during map creation. Overall
struct size and number of cachelines doesn't change from the
reordering. struct bpf_map is usually first member and embedded
in map structs in specific map implementations, so also avoid those
members to sit at the end where it could potentially share the
cacheline with first map values e.g. in the array since remote
CPUs could trigger map updates just as well for those (easily
dirtying members like max_entries intentionally as well) while
having subsequent values in cache.

Quoting from Google's Project Zero blog [1]:

  Additionally, at least on the Intel machine on which this was
  tested, bouncing modified cache lines between cores is slow,
  apparently because the MESI protocol is used for cache coherence
  [8]. Changing the reference counter of an eBPF array on one
  physical CPU core causes the cache line containing the reference
  counter to be bounced over to that CPU core, making reads of the
  reference counter on all other CPU cores slow until the changed
  reference counter has been written back to memory. Because the
  length and the reference counter of an eBPF array are stored in
  the same cache line, this also means that changing the reference
  counter on one physical CPU core causes reads of the eBPF array's
  length to be slow on other physical CPU cores (intentional false
  sharing).

While this doesn't 'control' the out-of-bounds speculation through
masking the index as in commit b2157399cc98, triggering a manipulation
of the map's reference counter is really trivial, so lets not allow
to easily affect max_entries from it.

Splitting to separate cachelines also generally makes sense from
a performance perspective anyway in that fast-path won't have a
cache miss if the map gets pinned, reused in other progs, etc out
of control path, thus also avoids unintentional false sharing.

  [1] https://googleprojectzero.blogspot.ch/2018/01/reading-privileged-memory-with-side.html

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
6 years agoipv6: remove null_entry before adding default route
Wei Wang [Mon, 8 Jan 2018 18:34:00 +0000 (10:34 -0800)]
ipv6: remove null_entry before adding default route

In the current code, when creating a new fib6 table, tb6_root.leaf gets
initialized to net->ipv6.ip6_null_entry.
If a default route is being added with rt->rt6i_metric = 0xffffffff,
fib6_add() will add this route after net->ipv6.ip6_null_entry. As
null_entry is shared, it could cause problem.

In order to fix it, set fn->leaf to NULL before calling
fib6_add_rt2node() when trying to add the first default route.
And reset fn->leaf to null_entry when adding fails or when deleting the
last default route.

syzkaller reported the following issue which is fixed by this commit:

WARNING: suspicious RCU usage
4.15.0-rc5+ #171 Not tainted
-----------------------------
net/ipv6/ip6_fib.c:1702 suspicious rcu_dereference_protected() usage!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
4 locks held by swapper/0/0:
 #0:  ((&net->ipv6.ip6_fib_timer)){+.-.}, at: [<00000000d43f631b>] lockdep_copy_map include/linux/lockdep.h:178 [inline]
 #0:  ((&net->ipv6.ip6_fib_timer)){+.-.}, at: [<00000000d43f631b>] call_timer_fn+0x1c6/0x820 kernel/time/timer.c:1310
 #1:  (&(&net->ipv6.fib6_gc_lock)->rlock){+.-.}, at: [<000000002ff9d65c>] spin_lock_bh include/linux/spinlock.h:315 [inline]
 #1:  (&(&net->ipv6.fib6_gc_lock)->rlock){+.-.}, at: [<000000002ff9d65c>] fib6_run_gc+0x9d/0x3c0 net/ipv6/ip6_fib.c:2007
 #2:  (rcu_read_lock){....}, at: [<0000000091db762d>] __fib6_clean_all+0x0/0x3a0 net/ipv6/ip6_fib.c:1560
 #3:  (&(&tb->tb6_lock)->rlock){+.-.}, at: [<000000009e503581>] spin_lock_bh include/linux/spinlock.h:315 [inline]
 #3:  (&(&tb->tb6_lock)->rlock){+.-.}, at: [<000000009e503581>] __fib6_clean_all+0x1d0/0x3a0 net/ipv6/ip6_fib.c:1948

stack backtrace:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.15.0-rc5+ #171
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:53
 lockdep_rcu_suspicious+0x123/0x170 kernel/locking/lockdep.c:4585
 fib6_del+0xcaa/0x11b0 net/ipv6/ip6_fib.c:1701
 fib6_clean_node+0x3aa/0x4f0 net/ipv6/ip6_fib.c:1892
 fib6_walk_continue+0x46c/0x8a0 net/ipv6/ip6_fib.c:1815
 fib6_walk+0x91/0xf0 net/ipv6/ip6_fib.c:1863
 fib6_clean_tree+0x1e6/0x340 net/ipv6/ip6_fib.c:1933
 __fib6_clean_all+0x1f4/0x3a0 net/ipv6/ip6_fib.c:1949
 fib6_clean_all net/ipv6/ip6_fib.c:1960 [inline]
 fib6_run_gc+0x16b/0x3c0 net/ipv6/ip6_fib.c:2016
 fib6_gc_timer_cb+0x20/0x30 net/ipv6/ip6_fib.c:2033
 call_timer_fn+0x228/0x820 kernel/time/timer.c:1320
 expire_timers kernel/time/timer.c:1357 [inline]
 __run_timers+0x7ee/0xb70 kernel/time/timer.c:1660
 run_timer_softirq+0x4c/0xb0 kernel/time/timer.c:1686
 __do_softirq+0x2d7/0xb85 kernel/softirq.c:285
 invoke_softirq kernel/softirq.c:365 [inline]
 irq_exit+0x1cc/0x200 kernel/softirq.c:405
 exiting_irq arch/x86/include/asm/apic.h:540 [inline]
 smp_apic_timer_interrupt+0x16b/0x700 arch/x86/kernel/apic/apic.c:1052
 apic_timer_interrupt+0xa9/0xb0 arch/x86/entry/entry_64.S:904
 </IRQ>

Reported-by: syzbot <syzkaller@googlegroups.com>
Fixes: 66f5d6ce53e6 ("ipv6: replace rwlock with rcu and spinlock in fib6_table")
Signed-off-by: Wei Wang <weiwan@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agoMerge branch 'Ether-fixes-for-the-SolutionEngine771x-boards'
David S. Miller [Tue, 9 Jan 2018 17:21:14 +0000 (12:21 -0500)]
Merge branch 'Ether-fixes-for-the-SolutionEngine771x-boards'

Sergei Shtylyov says:

====================
Ether fixes for the SolutionEngine771x boards

Here's the series of 2 patches against Linus' repo. This series should
(hoplefully) fix the Ether support on the SolutionEngine771x boards...

[1/2] SolutionEngine771x: fix Ether platform data
[2/2] SolutionEngine771x: add Ether TSU resource
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agoSolutionEngine771x: add Ether TSU resource
Sergei Shtylyov [Sat, 6 Jan 2018 18:53:27 +0000 (21:53 +0300)]
SolutionEngine771x: add Ether TSU resource

After the  Ether platform data is fixed, the driver probe() method would
still fail since the 'struct sh_eth_cpu_data' corresponding  to SH771x
indicates the presence of TSU but the memory resource for it is absent.
Add the missing TSU resource  to both Ether devices and fix the harmless
off-by-one error in the main memory resources, while at it...

Fixes: 4986b996882d ("net: sh_eth: remove the SH_TSU_ADDR")
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agoSolutionEngine771x: fix Ether platform data
Sergei Shtylyov [Sat, 6 Jan 2018 18:53:26 +0000 (21:53 +0300)]
SolutionEngine771x: fix Ether platform data

The 'sh_eth' driver's probe() method would fail  on the SolutionEngine7710
board and crash on SolutionEngine7712 board  as the platform code is
hopelessly behind the driver's platform data --  it passes the PHY address
instead of 'struct sh_eth_plat_data *'; pass the latter to the driver in
order to fix the bug...

Fixes: 71557a37adb5 ("[netdrvr] sh_eth: Add SH7619 support")
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agodocs-rst: networking: wire up msg_zerocopy
Mike Rapoport [Mon, 8 Jan 2018 06:50:17 +0000 (08:50 +0200)]
docs-rst: networking: wire up msg_zerocopy

Fix the following 'make htmldocs' complaint:

Documentation/networking/msg_zerocopy.rst:: WARNING: document isn't included in any toctree.

Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agonet: ipv4: emulate READ_ONCE() on ->hdrincl bit-field in raw_sendmsg()
Nicolai Stange [Mon, 8 Jan 2018 14:54:44 +0000 (15:54 +0100)]
net: ipv4: emulate READ_ONCE() on ->hdrincl bit-field in raw_sendmsg()

Commit 8f659a03a0ba ("net: ipv4: fix for a race condition in
raw_sendmsg") fixed the issue of possibly inconsistent ->hdrincl handling
due to concurrent updates by reading this bit-field member into a local
variable and using the thus stabilized value in subsequent tests.

However, aforementioned commit also adds the (correct) comment that

  /* hdrincl should be READ_ONCE(inet->hdrincl)
   * but READ_ONCE() doesn't work with bit fields
   */

because as it stands, the compiler is free to shortcut or even eliminate
the local variable at its will.

Note that I have not seen anything like this happening in reality and thus,
the concern is a theoretical one.

However, in order to be on the safe side, emulate a READ_ONCE() on the
bit-field by doing it on the local 'hdrincl' variable itself:

int hdrincl = inet->hdrincl;
hdrincl = READ_ONCE(hdrincl);

This breaks the chain in the sense that the compiler is not allowed
to replace subsequent reads from hdrincl with reloads from inet->hdrincl.

Fixes: 8f659a03a0ba ("net: ipv4: fix for a race condition in raw_sendmsg")
Signed-off-by: Nicolai Stange <nstange@suse.de>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agonet: caif: use strlcpy() instead of strncpy()
Xiongfeng Wang [Mon, 8 Jan 2018 11:43:00 +0000 (19:43 +0800)]
net: caif: use strlcpy() instead of strncpy()

gcc-8 reports

net/caif/caif_dev.c: In function 'caif_enroll_dev':
./include/linux/string.h:245:9: warning: '__builtin_strncpy' output may
be truncated copying 15 bytes from a string of length 15
[-Wstringop-truncation]

net/caif/cfctrl.c: In function 'cfctrl_linkup_request':
./include/linux/string.h:245:9: warning: '__builtin_strncpy' output may
be truncated copying 15 bytes from a string of length 15
[-Wstringop-truncation]

net/caif/cfcnfg.c: In function 'caif_connect_client':
./include/linux/string.h:245:9: warning: '__builtin_strncpy' output may
be truncated copying 15 bytes from a string of length 15
[-Wstringop-truncation]

The compiler require that the input param 'len' of strncpy() should be
greater than the length of the src string, so that '\0' is copied as
well. We can just use strlcpy() to avoid this warning.

Signed-off-by: Xiongfeng Wang <xiongfeng.wang@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>