platform/kernel/linux-rpi.git
6 years agox86/get_user: Use pointer masking to limit speculation
Dan Williams [Tue, 30 Jan 2018 01:02:54 +0000 (17:02 -0800)]
x86/get_user: Use pointer masking to limit speculation

Quoting Linus:

    I do think that it would be a good idea to very expressly document
    the fact that it's not that the user access itself is unsafe. I do
    agree that things like "get_user()" want to be protected, but not
    because of any direct bugs or problems with get_user() and friends,
    but simply because get_user() is an excellent source of a pointer
    that is obviously controlled from a potentially attacking user
    space. So it's a prime candidate for then finding _subsequent_
    accesses that can then be used to perturb the cache.

Unlike the __get_user() case get_user() includes the address limit check
near the pointer de-reference. With that locality the speculation can be
mitigated with pointer narrowing rather than a barrier, i.e.
array_index_nospec(). Where the narrowing is performed by:

cmp %limit, %ptr
sbb %mask, %mask
and %mask, %ptr

With respect to speculation the value of %ptr is either less than %limit
or NULL.

Co-developed-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: Kees Cook <keescook@chromium.org>
Cc: kernel-hardening@lists.openwall.com
Cc: gregkh@linuxfoundation.org
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: torvalds@linux-foundation.org
Cc: alan@linux.intel.com
Link: https://lkml.kernel.org/r/151727417469.33451.11804043010080838495.stgit@dwillia2-desk3.amr.corp.intel.com
6 years agox86/uaccess: Use __uaccess_begin_nospec() and uaccess_try_nospec
Dan Williams [Tue, 30 Jan 2018 01:02:49 +0000 (17:02 -0800)]
x86/uaccess: Use __uaccess_begin_nospec() and uaccess_try_nospec

Quoting Linus:

    I do think that it would be a good idea to very expressly document
    the fact that it's not that the user access itself is unsafe. I do
    agree that things like "get_user()" want to be protected, but not
    because of any direct bugs or problems with get_user() and friends,
    but simply because get_user() is an excellent source of a pointer
    that is obviously controlled from a potentially attacking user
    space. So it's a prime candidate for then finding _subsequent_
    accesses that can then be used to perturb the cache.

__uaccess_begin_nospec() covers __get_user() and copy_from_iter() where the
limit check is far away from the user pointer de-reference. In those cases
a barrier_nospec() prevents speculation with a potential pointer to
privileged memory. uaccess_try_nospec covers get_user_try.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Suggested-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: Kees Cook <keescook@chromium.org>
Cc: kernel-hardening@lists.openwall.com
Cc: gregkh@linuxfoundation.org
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: alan@linux.intel.com
Link: https://lkml.kernel.org/r/151727416953.33451.10508284228526170604.stgit@dwillia2-desk3.amr.corp.intel.com
6 years agox86/usercopy: Replace open coded stac/clac with __uaccess_{begin, end}
Dan Williams [Tue, 30 Jan 2018 01:02:44 +0000 (17:02 -0800)]
x86/usercopy: Replace open coded stac/clac with __uaccess_{begin, end}

In preparation for converting some __uaccess_begin() instances to
__uacess_begin_nospec(), make sure all 'from user' uaccess paths are
using the _begin(), _end() helpers rather than open-coded stac() and
clac().

No functional changes.

Suggested-by: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: kernel-hardening@lists.openwall.com
Cc: gregkh@linuxfoundation.org
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: torvalds@linux-foundation.org
Cc: alan@linux.intel.com
Link: https://lkml.kernel.org/r/151727416438.33451.17309465232057176966.stgit@dwillia2-desk3.amr.corp.intel.com
6 years agox86: Introduce __uaccess_begin_nospec() and uaccess_try_nospec
Dan Williams [Tue, 30 Jan 2018 01:02:39 +0000 (17:02 -0800)]
x86: Introduce __uaccess_begin_nospec() and uaccess_try_nospec

For __get_user() paths, do not allow the kernel to speculate on the value
of a user controlled pointer. In addition to the 'stac' instruction for
Supervisor Mode Access Protection (SMAP), a barrier_nospec() causes the
access_ok() result to resolve in the pipeline before the CPU might take any
speculative action on the pointer value. Given the cost of 'stac' the
speculation barrier is placed after 'stac' to hopefully overlap the cost of
disabling SMAP with the cost of flushing the instruction pipeline.

Since __get_user is a major kernel interface that deals with user
controlled pointers, the __uaccess_begin_nospec() mechanism will prevent
speculative execution past an access_ok() permission check. While
speculative execution past access_ok() is not enough to lead to a kernel
memory leak, it is a necessary precondition.

To be clear, __uaccess_begin_nospec() is addressing a class of potential
problems near __get_user() usages.

Note, that while the barrier_nospec() in __uaccess_begin_nospec() is used
to protect __get_user(), pointer masking similar to array_index_nospec()
will be used for get_user() since it incorporates a bounds check near the
usage.

uaccess_try_nospec provides the same mechanism for get_user_try.

No functional changes.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Suggested-by: Andi Kleen <ak@linux.intel.com>
Suggested-by: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: kernel-hardening@lists.openwall.com
Cc: gregkh@linuxfoundation.org
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: alan@linux.intel.com
Link: https://lkml.kernel.org/r/151727415922.33451.5796614273104346583.stgit@dwillia2-desk3.amr.corp.intel.com
6 years agox86: Introduce barrier_nospec
Dan Williams [Tue, 30 Jan 2018 01:02:33 +0000 (17:02 -0800)]
x86: Introduce barrier_nospec

Rename the open coded form of this instruction sequence from
rdtsc_ordered() into a generic barrier primitive, barrier_nospec().

One of the mitigations for Spectre variant1 vulnerabilities is to fence
speculative execution after successfully validating a bounds check. I.e.
force the result of a bounds check to resolve in the instruction pipeline
to ensure speculative execution honors that result before potentially
operating on out-of-bounds data.

No functional changes.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Suggested-by: Andi Kleen <ak@linux.intel.com>
Suggested-by: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: kernel-hardening@lists.openwall.com
Cc: gregkh@linuxfoundation.org
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: alan@linux.intel.com
Link: https://lkml.kernel.org/r/151727415361.33451.9049453007262764675.stgit@dwillia2-desk3.amr.corp.intel.com
6 years agox86: Implement array_index_mask_nospec
Dan Williams [Tue, 30 Jan 2018 01:02:28 +0000 (17:02 -0800)]
x86: Implement array_index_mask_nospec

array_index_nospec() uses a mask to sanitize user controllable array
indexes, i.e. generate a 0 mask if 'index' >= 'size', and a ~0 mask
otherwise. While the default array_index_mask_nospec() handles the
carry-bit from the (index - size) result in software.

The x86 array_index_mask_nospec() does the same, but the carry-bit is
handled in the processor CF flag without conditional instructions in the
control flow.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: kernel-hardening@lists.openwall.com
Cc: gregkh@linuxfoundation.org
Cc: alan@linux.intel.com
Link: https://lkml.kernel.org/r/151727414808.33451.1873237130672785331.stgit@dwillia2-desk3.amr.corp.intel.com
6 years agoarray_index_nospec: Sanitize speculative array de-references
Dan Williams [Tue, 30 Jan 2018 01:02:22 +0000 (17:02 -0800)]
array_index_nospec: Sanitize speculative array de-references

array_index_nospec() is proposed as a generic mechanism to mitigate
against Spectre-variant-1 attacks, i.e. an attack that bypasses boundary
checks via speculative execution. The array_index_nospec()
implementation is expected to be safe for current generation CPUs across
multiple architectures (ARM, x86).

Based on an original implementation by Linus Torvalds, tweaked to remove
speculative flows by Alexei Starovoitov, and tweaked again by Linus to
introduce an x86 assembly implementation for the mask generation.

Co-developed-by: Linus Torvalds <torvalds@linux-foundation.org>
Co-developed-by: Alexei Starovoitov <ast@kernel.org>
Suggested-by: Cyril Novikov <cnovikov@lynx.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: kernel-hardening@lists.openwall.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: gregkh@linuxfoundation.org
Cc: torvalds@linux-foundation.org
Cc: alan@linux.intel.com
Link: https://lkml.kernel.org/r/151727414229.33451.18411580953862676575.stgit@dwillia2-desk3.amr.corp.intel.com
6 years agoDocumentation: Document array_index_nospec
Mark Rutland [Tue, 30 Jan 2018 01:02:16 +0000 (17:02 -0800)]
Documentation: Document array_index_nospec

Document the rationale and usage of the new array_index_nospec() helper.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: linux-arch@vger.kernel.org
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: gregkh@linuxfoundation.org
Cc: kernel-hardening@lists.openwall.com
Cc: torvalds@linux-foundation.org
Cc: alan@linux.intel.com
Link: https://lkml.kernel.org/r/151727413645.33451.15878817161436755393.stgit@dwillia2-desk3.amr.corp.intel.com
6 years agox86/asm: Move 'status' from thread_struct to thread_info
Andy Lutomirski [Sun, 28 Jan 2018 18:38:50 +0000 (10:38 -0800)]
x86/asm: Move 'status' from thread_struct to thread_info

The TS_COMPAT bit is very hot and is accessed from code paths that mostly
also touch thread_info::flags.  Move it into struct thread_info to improve
cache locality.

The only reason it was in thread_struct is that there was a brief period
during which arch-specific fields were not allowed in struct thread_info.

Linus suggested further changing:

  ti->status &= ~(TS_COMPAT|TS_I386_REGS_POKED);

to:

  if (unlikely(ti->status & (TS_COMPAT|TS_I386_REGS_POKED)))
          ti->status &= ~(TS_COMPAT|TS_I386_REGS_POKED);

on the theory that frequently dirtying the cacheline even in pure 64-bit
code that never needs to modify status hurts performance.  That could be a
reasonable followup patch, but I suspect it matters less on top of this
patch.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Kernel Hardening <kernel-hardening@lists.openwall.com>
Link: https://lkml.kernel.org/r/03148bcc1b217100e6e8ecf6a5468c45cf4304b6.1517164461.git.luto@kernel.org
6 years agox86/entry/64: Push extra regs right away
Andy Lutomirski [Sun, 28 Jan 2018 18:38:49 +0000 (10:38 -0800)]
x86/entry/64: Push extra regs right away

With the fast path removed there is no point in splitting the push of the
normal and the extra register set. Just push the extra regs right away.

[ tglx: Split out from 'x86/entry/64: Remove the SYSCALL64 fast path' ]

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Kernel Hardening <kernel-hardening@lists.openwall.com>
Link: https://lkml.kernel.org/r/462dff8d4d64dfbfc851fbf3130641809d980ecd.1517164461.git.luto@kernel.org
6 years agox86/entry/64: Remove the SYSCALL64 fast path
Andy Lutomirski [Sun, 28 Jan 2018 18:38:49 +0000 (10:38 -0800)]
x86/entry/64: Remove the SYSCALL64 fast path

The SYCALLL64 fast path was a nice, if small, optimization back in the good
old days when syscalls were actually reasonably fast.  Now there is PTI to
slow everything down, and indirect branches are verboten, making everything
messier.  The retpoline code in the fast path is particularly nasty.

Just get rid of the fast path. The slow path is barely slower.

[ tglx: Split out the 'push all extra regs' part ]

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Kernel Hardening <kernel-hardening@lists.openwall.com>
Link: https://lkml.kernel.org/r/462dff8d4d64dfbfc851fbf3130641809d980ecd.1517164461.git.luto@kernel.org
6 years agox86/spectre: Check CONFIG_RETPOLINE in command line parser
Dou Liyang [Tue, 30 Jan 2018 06:13:50 +0000 (14:13 +0800)]
x86/spectre: Check CONFIG_RETPOLINE in command line parser

The spectre_v2 option 'auto' does not check whether CONFIG_RETPOLINE is
enabled. As a consequence it fails to emit the appropriate warning and sets
feature flags which have no effect at all.

Add the missing IS_ENABLED() check.

Fixes: da285121560e ("x86/spectre: Add boot time option to select Spectre v2 mitigation")
Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ak@linux.intel.com
Cc: peterz@infradead.org
Cc: Tomohiro" <misono.tomohiro@jp.fujitsu.com>
Cc: dave.hansen@intel.com
Cc: bp@alien8.de
Cc: arjan@linux.intel.com
Cc: dwmw@amazon.co.uk
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/f5892721-7528-3647-08fb-f8d10e65ad87@cn.fujitsu.com
6 years agox86/mm: Fix overlap of i386 CPU_ENTRY_AREA with FIX_BTMAP
William Grant [Tue, 30 Jan 2018 11:22:55 +0000 (22:22 +1100)]
x86/mm: Fix overlap of i386 CPU_ENTRY_AREA with FIX_BTMAP

Since commit 92a0f81d8957 ("x86/cpu_entry_area: Move it out of the
fixmap"), i386's CPU_ENTRY_AREA has been mapped to the memory area just
below FIXADDR_START. But already immediately before FIXADDR_START is the
FIX_BTMAP area, which means that early_ioremap can collide with the entry
area.

It's especially bad on PAE where FIX_BTMAP_BEGIN gets aligned to exactly
match CPU_ENTRY_AREA_BASE, so the first early_ioremap slot clobbers the
IDT and causes interrupts during early boot to reset the system.

The overlap wasn't a problem before the CPU entry area was introduced,
as the fixmap has classically been preceded by the pkmap or vmalloc
areas, neither of which is used until early_ioremap is out of the
picture.

Relocate CPU_ENTRY_AREA to below FIX_BTMAP, not just below the permanent
fixmap area.

Fixes: commit 92a0f81d8957 ("x86/cpu_entry_area: Move it out of the fixmap")
Signed-off-by: William Grant <william.grant@canonical.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/7041d181-a019-e8b9-4e4e-48215f841e2c@canonical.com
6 years agoobjtool: Warn on stripped section symbol
Josh Poimboeuf [Tue, 30 Jan 2018 04:00:41 +0000 (22:00 -0600)]
objtool: Warn on stripped section symbol

With the following fix:

  2a0098d70640 ("objtool: Fix seg fault with gold linker")

... a seg fault was avoided, but the original seg fault condition in
objtool wasn't fixed.  Replace the seg fault with an error message.

Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/dc4585a70d6b975c99fc51d1957ccdde7bd52f3a.1517284349.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
6 years agoobjtool: Add support for alternatives at the end of a section
Josh Poimboeuf [Tue, 30 Jan 2018 04:00:40 +0000 (22:00 -0600)]
objtool: Add support for alternatives at the end of a section

Now that the previous patch gave objtool the ability to read retpoline
alternatives, it shows a new warning:

  arch/x86/entry/entry_64.o: warning: objtool: .entry_trampoline: don't know how to handle alternatives at end of section

This is due to the JMP_NOSPEC in entry_SYSCALL_64_trampoline().

Previously, objtool ignored this situation because it wasn't needed, and
it would have required a bit of extra code.  Now that this case exists,
add proper support for it.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/2a30a3c2158af47d891a76e69bb1ef347e0443fd.1517284349.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
6 years agoobjtool: Improve retpoline alternative handling
Josh Poimboeuf [Tue, 30 Jan 2018 04:00:39 +0000 (22:00 -0600)]
objtool: Improve retpoline alternative handling

Currently objtool requires all retpolines to be:

  a) patched in with alternatives; and

  b) annotated with ANNOTATE_NOSPEC_ALTERNATIVE.

If you forget to do both of the above, objtool segfaults trying to
dereference a NULL 'insn->call_dest' pointer.

Avoid that situation and print a more helpful error message:

  quirks.o: warning: objtool: efi_delete_dummy_variable()+0x99: unsupported intra-function call
  quirks.o: warning: objtool: If this is a retpoline, please patch it in with alternatives and annotate it with ANNOTATE_NOSPEC_ALTERNATIVE.

Future improvements can be made to make objtool smarter with respect to
retpolines, but this is a good incremental improvement for now.

Reported-and-tested-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/819e50b6d9c2e1a22e34c1a636c0b2057cc8c6e5.1517284349.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
6 years agoMerge tag 'v4.15' into x86/pti, to be able to merge dependent changes
Ingo Molnar [Tue, 30 Jan 2018 14:08:27 +0000 (15:08 +0100)]
Merge tag 'v4.15' into x86/pti, to be able to merge dependent changes

Time has come to switch PTI development over to a v4.15 base - we'll still
try to make sure that all PTI fixes backport cleanly to v4.14 and earlier.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
6 years agoLinux 4.15
Linus Torvalds [Sun, 28 Jan 2018 21:20:33 +0000 (13:20 -0800)]
Linux 4.15

6 years agoMerge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Sun, 28 Jan 2018 20:24:36 +0000 (12:24 -0800)]
Merge branch 'x86-pti-for-linus' of git://git./linux/kernel/git/tip/tip

Pull x86 retpoline fixlet from Thomas Gleixner:
 "Remove the ESP/RSP thunks for retpoline as they cannot ever work.

  Get rid of them before they show up in a release"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/retpoline: Remove the esp/rsp thunk

6 years agoMerge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Sun, 28 Jan 2018 20:19:23 +0000 (12:19 -0800)]
Merge branch 'x86-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull x86 fixes from Thomas Gleixner:
 "A set of small fixes for 4.15:

   - Fix vmapped stack synchronization on systems with 4-level paging
     and a large amount of memory caused by a missing 5-level folding
     which made the pgd synchronization logic to fail and causing double
     faults.

   - Add a missing sanity check in the vmalloc_fault() logic on 5-level
     paging systems.

   - Bring back protection against accessing a freed initrd in the
     microcode loader which was lost by a wrong merge conflict
     resolution.

   - Extend the Broadwell micro code loading sanity check.

   - Add a missing ENDPROC annotation in ftrace assembly code which
     makes ORC unhappy.

   - Prevent loading the AMD power module on !AMD platforms. The load
     itself is uncritical, but an unload attempt results in a kernel
     crash.

   - Update Peter Anvins role in the MAINTAINERS file"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/ftrace: Add one more ENDPROC annotation
  x86: Mark hpa as a "Designated Reviewer" for the time being
  x86/mm/64: Tighten up vmalloc_fault() sanity checks on 5-level kernels
  x86/mm/64: Fix vmapped stack syncing on very-large-memory 4-level systems
  x86/microcode: Fix again accessing initrd after having been freed
  x86/microcode/intel: Extend BDW late-loading further with LLC size check
  perf/x86/amd/power: Do not load AMD power module on !AMD platforms

6 years agoMerge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Sun, 28 Jan 2018 20:17:35 +0000 (12:17 -0800)]
Merge branch 'timers-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull timer fix from Thomas Gleixner:
 "A single fix for a ~10 years old problem which causes high resolution
  timers to stop after a CPU unplug/plug cycle due to a stale flag in
  the per CPU hrtimer base struct.

  Paul McKenney was hunting this for about a year, but the heisenbug
  nature made it resistant against debug attempts for quite some time"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  hrtimer: Reset hrtimer cpu base proper on CPU hotplug

6 years agoMerge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Sun, 28 Jan 2018 19:51:45 +0000 (11:51 -0800)]
Merge branch 'sched-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull scheduler fix from Thomas Gleixner:
 "A single bug fix to prevent a subtle deadlock in the scheduler core
  code vs cpu hotplug"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/core: Fix cpu.max vs. cpuhotplug deadlock

6 years agoMerge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Sun, 28 Jan 2018 19:48:25 +0000 (11:48 -0800)]
Merge branch 'perf-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull perf fixes from Thomas Gleixner:
 "Four patches which all address lock inversions and deadlocks in the
  perf core code and the Intel debug store"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86: Fix perf,x86,cpuhp deadlock
  perf/core: Fix ctx::mutex deadlock
  perf/core: Fix another perf,trace,cpuhp lock inversion
  perf/core: Fix lock inversion between perf,trace,cpuhp

6 years agoMerge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Sun, 28 Jan 2018 19:20:35 +0000 (11:20 -0800)]
Merge branch 'locking-urgent-for-linus' of git://git./linux/kernel/git/tip/tip

Pull locking fixes from Thomas Gleixner:
 "Two final locking fixes for 4.15:

   - Repair the OWNER_DIED logic in the futex code which got wreckaged
     with the recent fix for a subtle race condition.

   - Prevent the hard lockup detector from triggering when dumping all
     held locks in the system"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/lockdep: Avoid triggering hardlockup from debug_show_all_locks()
  futex: Fix OWNER_DEAD fixup

6 years agox86/ftrace: Add one more ENDPROC annotation
Josh Poimboeuf [Sun, 28 Jan 2018 02:21:50 +0000 (20:21 -0600)]
x86/ftrace: Add one more ENDPROC annotation

When ORC support was added for the ftrace_64.S code, an ENDPROC
for function_hook() was missed. This results in the following warning:

  arch/x86/kernel/ftrace_64.o: warning: objtool: .entry.text+0x0: unreachable instruction

Fixes: e2ac83d74a4d ("x86/ftrace: Fix ORC unwinding from ftrace handlers")
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lkml.kernel.org/r/20180128022150.dqierscqmt3uwwsr@treble
6 years agox86/speculation: Simplify indirect_branch_prediction_barrier()
Borislav Petkov [Sat, 27 Jan 2018 16:24:34 +0000 (16:24 +0000)]
x86/speculation: Simplify indirect_branch_prediction_barrier()

Make it all a function which does the WRMSR instead of having a hairy
inline asm.

[dwmw2: export it, fix CONFIG_RETPOLINE issues]

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ak@linux.intel.com
Cc: dave.hansen@intel.com
Cc: karahmed@amazon.de
Cc: arjan@linux.intel.com
Cc: torvalds@linux-foundation.org
Cc: peterz@infradead.org
Cc: bp@alien8.de
Cc: pbonzini@redhat.com
Cc: tim.c.chen@linux.intel.com
Cc: gregkh@linux-foundation.org
Link: https://lkml.kernel.org/r/1517070274-12128-4-git-send-email-dwmw@amazon.co.uk
6 years agox86/retpoline: Simplify vmexit_fill_RSB()
Borislav Petkov [Sat, 27 Jan 2018 16:24:33 +0000 (16:24 +0000)]
x86/retpoline: Simplify vmexit_fill_RSB()

Simplify it to call an asm-function instead of pasting 41 insn bytes at
every call site. Also, add alignment to the macro as suggested here:

  https://support.google.com/faqs/answer/7625886

[dwmw2: Clean up comments, let it clobber %ebx and just tell the compiler]

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ak@linux.intel.com
Cc: dave.hansen@intel.com
Cc: karahmed@amazon.de
Cc: arjan@linux.intel.com
Cc: torvalds@linux-foundation.org
Cc: peterz@infradead.org
Cc: bp@alien8.de
Cc: pbonzini@redhat.com
Cc: tim.c.chen@linux.intel.com
Cc: gregkh@linux-foundation.org
Link: https://lkml.kernel.org/r/1517070274-12128-3-git-send-email-dwmw@amazon.co.uk
6 years agox86/cpufeatures: Clean up Spectre v2 related CPUID flags
David Woodhouse [Sat, 27 Jan 2018 16:24:32 +0000 (16:24 +0000)]
x86/cpufeatures: Clean up Spectre v2 related CPUID flags

We want to expose the hardware features simply in /proc/cpuinfo as "ibrs",
"ibpb" and "stibp". Since AMD has separate CPUID bits for those, use them
as the user-visible bits.

When the Intel SPEC_CTRL bit is set which indicates both IBRS and IBPB
capability, set those (AMD) bits accordingly. Likewise if the Intel STIBP
bit is set, set the AMD STIBP that's used for the generic hardware
capability.

Hide the rest from /proc/cpuinfo by putting "" in the comments. Including
RETPOLINE and RETPOLINE_AMD which shouldn't be visible there. There are
patches to make the sysfs vulnerabilities information non-readable by
non-root, and the same should apply to all information about which
mitigations are actually in use. Those *shouldn't* appear in /proc/cpuinfo.

The feature bit for whether IBPB is actually used, which is needed for
ALTERNATIVEs, is renamed to X86_FEATURE_USE_IBPB.

Originally-by: Borislav Petkov <bp@suse.de>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: ak@linux.intel.com
Cc: dave.hansen@intel.com
Cc: karahmed@amazon.de
Cc: arjan@linux.intel.com
Cc: torvalds@linux-foundation.org
Cc: peterz@infradead.org
Cc: bp@alien8.de
Cc: pbonzini@redhat.com
Cc: tim.c.chen@linux.intel.com
Cc: gregkh@linux-foundation.org
Link: https://lkml.kernel.org/r/1517070274-12128-2-git-send-email-dwmw@amazon.co.uk
6 years agox86/cpu/bugs: Make retpoline module warning conditional
Thomas Gleixner [Sat, 27 Jan 2018 14:45:14 +0000 (15:45 +0100)]
x86/cpu/bugs: Make retpoline module warning conditional

If sysfs is disabled and RETPOLINE not defined:

arch/x86/kernel/cpu/bugs.c:97:13: warning: ‘spectre_v2_bad_module’ defined but not used
[-Wunused-variable]
 static bool spectre_v2_bad_module;

Hide it.

Fixes: caf7501a1b4e ("module/retpoline: Warn about missing retpoline in module")
Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
6 years agohrtimer: Reset hrtimer cpu base proper on CPU hotplug
Thomas Gleixner [Fri, 26 Jan 2018 13:54:32 +0000 (14:54 +0100)]
hrtimer: Reset hrtimer cpu base proper on CPU hotplug

The hrtimer interrupt code contains a hang detection and mitigation
mechanism, which prevents that a long delayed hrtimer interrupt causes a
continous retriggering of interrupts which prevent the system from making
progress. If a hang is detected then the timer hardware is programmed with
a certain delay into the future and a flag is set in the hrtimer cpu base
which prevents newly enqueued timers from reprogramming the timer hardware
prior to the chosen delay. The subsequent hrtimer interrupt after the delay
clears the flag and resumes normal operation.

If such a hang happens in the last hrtimer interrupt before a CPU is
unplugged then the hang_detected flag is set and stays that way when the
CPU is plugged in again. At that point the timer hardware is not armed and
it cannot be armed because the hang_detected flag is still active, so
nothing clears that flag. As a consequence the CPU does not receive hrtimer
interrupts and no timers expire on that CPU which results in RCU stalls and
other malfunctions.

Clear the flag along with some other less critical members of the hrtimer
cpu base to ensure starting from a clean state when a CPU is plugged in.

Thanks to Paul, Sebastian and Anna-Maria for their help to get down to the
root cause of that hard to reproduce heisenbug. Once understood it's
trivial and certainly justifies a brown paperbag.

Fixes: 41d2e4949377 ("hrtimer: Tune hrtimer_interrupt hang logic")
Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Sewior <bigeasy@linutronix.de>
Cc: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/alpine.DEB.2.20.1801261447590.2067@nanos
6 years agox86: Mark hpa as a "Designated Reviewer" for the time being
H. Peter Anvin [Thu, 25 Jan 2018 19:59:34 +0000 (11:59 -0800)]
x86: Mark hpa as a "Designated Reviewer" for the time being

Due to some unfortunate events, I have not been directly involved in
the x86 kernel patch flow for a while now.  I have also not been able
to ramp back up by now like I had hoped to, and after reviewing what I
will need to work on both internally at Intel and elsewhere in the near
term, it is clear that I am not going to be able to ramp back up until
late 2018 at the very earliest.

It is not acceptable to not recognize that this load is currently
taken by Ingo and Thomas without my direct participation, so I mark
myself as R: (designated reviewer) rather than M: (maintainer) until
further notice.  This is in fact recognizing the de facto situation
for the past few years.

I have obviously no intention of going away, and I will do everything
within my power to improve Linux on x86 and x86 for Linux.  This,
however, puts credit where it is due and reflects a change of focus.

This patch also removes stale entries for portions of the x86
architecture which have not been maintained separately from arch/x86
for a long time.  If there is a reason to re-introduce them then that
can happen later.

Signed-off-by: H. Peter Anvin <h.peter.anvin@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Bruce Schlobohm <bruce.schlobohm@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180125195934.5253-1-hpa@zytor.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
6 years agoMerge tag 'riscv-for-linus-4.15-maintainers' of git://git.kernel.org/pub/scm/linux...
Linus Torvalds [Fri, 26 Jan 2018 23:10:50 +0000 (15:10 -0800)]
Merge tag 'riscv-for-linus-4.15-maintainers' of git://git./linux/kernel/git/palmer/riscv-linux

Pull RISC-V update from Palmer Dabbelt:
 "RISC-V: We have a new mailing list and git repo!

  Sorry to send something essentially as late as possible (Friday after
  an rc9), but we managed to get a mailing list for the RISC-V Linux
  port. We've been using patches@groups.riscv.org for a while, but that
  list has some problems (it's Google Groups and it's shared over all
  RISC-V software projects). The new infaread.org list is much better.
  We just got it on Wednesday but I used it a bit on Thursday to shake
  out all the configuration problems and it appears to be in working
  order.

  When I updated the mailing list I noticed that the MAINTAINERS file
  was pointing to our github repo, but now that we have a kernel.org
  repo I'd like to point to that instead so I changed that as well.
  We'll be centralizing all RISC-V Linux related development here as
  that seems to be the saner way to go about it.

  I can understand if it's too late to get this into 4.15, but given
  that it's not a code change I was hoping it'd still be OK. It would be
  nice to have the new mailing list and git repo in the release tarballs
  so when people start to find bugs they'll get to the right place"

* tag 'riscv-for-linus-4.15-maintainers' of git://git.kernel.org/pub/scm/linux/kernel/git/palmer/riscv-linux:
  Update the RISC-V MAINTAINERS file

6 years agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Linus Torvalds [Fri, 26 Jan 2018 17:03:16 +0000 (09:03 -0800)]
Merge git://git./linux/kernel/git/davem/net

Pull networking fixes from David Miller:

 1) The per-network-namespace loopback device, and thus its namespace,
    can have its teardown deferred for a long time if a kernel created
    TCP socket closes and the namespace is exiting meanwhile. The kernel
    keeps trying to finish the close sequence until it times out (which
    takes quite some time).

    Fix this by forcing the socket closed in this situation, from Dan
    Streetman.

 2) Fix regression where we're trying to invoke the update_pmtu method
    on route types (in this case metadata tunnel routes) that don't
    implement the dst_ops method. Fix from Nicolas Dichtel.

 3) Fix long standing memory corruption issues in r8169 driver by
    performing the chip statistics DMA programming more correctly. From
    Francois Romieu.

 4) Handle local broadcast sends over VRF routes properly, from David
    Ahern.

 5) Don't refire the DCCP CCID2 timer endlessly, otherwise the socket
    can never be released. From Alexey Kodanev.

 6) Set poll flags properly in VSOCK protocol layer, from Stefan
    Hajnoczi.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  VSOCK: set POLLOUT | POLLWRNORM for TCP_CLOSING
  dccp: don't restart ccid2_hc_tx_rto_expire() if sk in closed state
  net: vrf: Add support for sends to local broadcast address
  r8169: fix memory corruption on retrieval of hardware statistics.
  net: don't call update_pmtu unconditionally
  net: tcp: close sock if net namespace is exiting

6 years agoMerge tag 'drm-fixes-for-v4.15-rc10-2' of git://people.freedesktop.org/~airlied/linux
Linus Torvalds [Fri, 26 Jan 2018 16:59:57 +0000 (08:59 -0800)]
Merge tag 'drm-fixes-for-v4.15-rc10-2' of git://people.freedesktop.org/~airlied/linux

Pull drm fixes from Dave Airlie:
 "A fairly urgent nouveau regression fix for broken irqs across
  suspend/resume came in. This was broken before but a patch in 4.15 has
  made it much more obviously broken and now s/r fails a lot more often.

  The fix removes freeing the irq across s/r which never should have
  been done anyways.

  Also two vc4 fixes for a NULL deference and some misrendering /
  flickering on screen"

* tag 'drm-fixes-for-v4.15-rc10-2' of git://people.freedesktop.org/~airlied/linux:
  drm/nouveau: Move irq setup/teardown to pci ctor/dtor
  drm/vc4: Fix NULL pointer dereference in vc4_save_hang_state()
  drm/vc4: Flush the caches before the bin jobs, as well.

6 years agoVSOCK: set POLLOUT | POLLWRNORM for TCP_CLOSING
Stefan Hajnoczi [Fri, 26 Jan 2018 11:48:25 +0000 (11:48 +0000)]
VSOCK: set POLLOUT | POLLWRNORM for TCP_CLOSING

select(2) with wfds but no rfds must return when the socket is shut down
by the peer.  This way userspace notices socket activity and gets -EPIPE
from the next write(2).

Currently select(2) does not return for virtio-vsock when a SEND+RCV
shutdown packet is received.  This is because vsock_poll() only sets
POLLOUT | POLLWRNORM for TCP_CLOSE, not the TCP_CLOSING state that the
socket is in when the shutdown is received.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agodccp: don't restart ccid2_hc_tx_rto_expire() if sk in closed state
Alexey Kodanev [Fri, 26 Jan 2018 12:14:16 +0000 (15:14 +0300)]
dccp: don't restart ccid2_hc_tx_rto_expire() if sk in closed state

ccid2_hc_tx_rto_expire() timer callback always restarts the timer
again and can run indefinitely (unless it is stopped outside), and after
commit 120e9dabaf55 ("dccp: defer ccid_hc_tx_delete() at dismantle time"),
which moved ccid_hc_tx_delete() (also includes sk_stop_timer()) from
dccp_destroy_sock() to sk_destruct(), this started to happen quite often.
The timer prevents releasing the socket, as a result, sk_destruct() won't
be called.

Found with LTP/dccp_ipsec tests running on the bonding device,
which later couldn't be unloaded after the tests were completed:

  unregister_netdevice: waiting for bond0 to become free. Usage count = 148

Fixes: 2a91aa396739 ("[DCCP] CCID2: Initial CCID2 (TCP-Like) implementation")
Signed-off-by: Alexey Kodanev <alexey.kodanev@oracle.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agoUpdate the RISC-V MAINTAINERS file
Palmer Dabbelt [Wed, 24 Jan 2018 21:26:11 +0000 (13:26 -0800)]
Update the RISC-V MAINTAINERS file

Now that we're upstream in Linux we've been able to make some
infrastructure changes so our port works a bit more like other ports.
Specifically:

* We now have a mailing list specific to the RISC-V Linux port, hosted
  at lists.infreadead.org.
* We now have a kernel.org git tree where work on our port is
  coordinated.

This patch changes the RISC-V maintainers entry to reflect these new
bits of infrastructure.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
6 years agox86/mm/64: Tighten up vmalloc_fault() sanity checks on 5-level kernels
Andy Lutomirski [Thu, 25 Jan 2018 21:12:15 +0000 (13:12 -0800)]
x86/mm/64: Tighten up vmalloc_fault() sanity checks on 5-level kernels

On a 5-level kernel, if a non-init mm has a top-level entry, it needs to
match init_mm's, but the vmalloc_fault() code skipped over the BUG_ON()
that would have checked it.

While we're at it, get rid of the rather confusing 4-level folded "pgd"
logic.

Cleans-up: b50858ce3e2a ("x86/mm/vmalloc: Add 5-level paging support")
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Neil Berrington <neil.berrington@datacore.com>
Link: https://lkml.kernel.org/r/2ae598f8c279b0a29baf75df207e6f2fdddc0a1b.1516914529.git.luto@kernel.org
6 years agox86/mm/64: Fix vmapped stack syncing on very-large-memory 4-level systems
Andy Lutomirski [Thu, 25 Jan 2018 21:12:14 +0000 (13:12 -0800)]
x86/mm/64: Fix vmapped stack syncing on very-large-memory 4-level systems

Neil Berrington reported a double-fault on a VM with 768GB of RAM that uses
large amounts of vmalloc space with PTI enabled.

The cause is that load_new_mm_cr3() was never fixed to take the 5-level pgd
folding code into account, so, on a 4-level kernel, the pgd synchronization
logic compiles away to exactly nothing.

Interestingly, the problem doesn't trigger with nopti.  I assume this is
because the kernel is mapped with global pages if we boot with nopti.  The
sequence of operations when we create a new task is that we first load its
mm while still running on the old stack (which crashes if the old stack is
unmapped in the new mm unless the TLB saves us), then we call
prepare_switch_to(), and then we switch to the new stack.
prepare_switch_to() pokes the new stack directly, which will populate the
mapping through vmalloc_fault().  I assume that we're getting lucky on
non-PTI systems -- the old stack's TLB entry stays alive long enough to
make it all the way through prepare_switch_to() and switch_to() so that we
make it to a valid stack.

Fixes: b50858ce3e2a ("x86/mm/vmalloc: Add 5-level paging support")
Reported-and-tested-by: Neil Berrington <neil.berrington@datacore.com>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: stable@vger.kernel.org
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Borislav Petkov <bp@alien8.de>
Link: https://lkml.kernel.org/r/346541c56caed61abbe693d7d2742b4a380c5001.1516914529.git.luto@kernel.org
6 years agox86/bugs: Drop one "mitigation" from dmesg
Borislav Petkov [Fri, 26 Jan 2018 12:11:39 +0000 (13:11 +0100)]
x86/bugs: Drop one "mitigation" from dmesg

Make

[    0.031118] Spectre V2 mitigation: Mitigation: Full generic retpoline

into

[    0.031118] Spectre V2: Mitigation: Full generic retpoline

to reduce the mitigation mitigations strings.

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: riel@redhat.com
Cc: ak@linux.intel.com
Cc: peterz@infradead.org
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: jikos@kernel.org
Cc: luto@amacapital.net
Cc: dave.hansen@intel.com
Cc: torvalds@linux-foundation.org
Cc: keescook@google.com
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: tim.c.chen@linux.intel.com
Cc: pjt@google.com
Link: https://lkml.kernel.org/r/20180126121139.31959-5-bp@alien8.de
6 years agox86/nospec: Fix header guards names
Borislav Petkov [Fri, 26 Jan 2018 12:11:37 +0000 (13:11 +0100)]
x86/nospec: Fix header guards names

... to adhere to the _ASM_X86_ naming scheme.

No functional change.

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: riel@redhat.com
Cc: ak@linux.intel.com
Cc: peterz@infradead.org
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: jikos@kernel.org
Cc: luto@amacapital.net
Cc: dave.hansen@intel.com
Cc: torvalds@linux-foundation.org
Cc: keescook@google.com
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: tim.c.chen@linux.intel.com
Cc: gregkh@linux-foundation.org
Cc: pjt@google.com
Link: https://lkml.kernel.org/r/20180126121139.31959-3-bp@alien8.de
6 years agox86/alternative: Print unadorned pointers
Borislav Petkov [Fri, 26 Jan 2018 12:11:36 +0000 (13:11 +0100)]
x86/alternative: Print unadorned pointers

After commit ad67b74d2469 ("printk: hash addresses printed with %p")
pointers are being hashed when printed. However, this makes the alternative
debug output completely useless. Switch to %px in order to see the
unadorned kernel pointers.

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: riel@redhat.com
Cc: ak@linux.intel.com
Cc: peterz@infradead.org
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: jikos@kernel.org
Cc: luto@amacapital.net
Cc: dave.hansen@intel.com
Cc: torvalds@linux-foundation.org
Cc: keescook@google.com
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: tim.c.chen@linux.intel.com
Cc: gregkh@linux-foundation.org
Cc: pjt@google.com
Link: https://lkml.kernel.org/r/20180126121139.31959-2-bp@alien8.de
6 years agox86/speculation: Add basic IBPB (Indirect Branch Prediction Barrier) support
David Woodhouse [Thu, 25 Jan 2018 16:14:15 +0000 (16:14 +0000)]
x86/speculation: Add basic IBPB (Indirect Branch Prediction Barrier) support

Expose indirect_branch_prediction_barrier() for use in subsequent patches.

[ tglx: Add IBPB status to spectre_v2 sysfs file ]

Co-developed-by: KarimAllah Ahmed <karahmed@amazon.de>
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: ak@linux.intel.com
Cc: ashok.raj@intel.com
Cc: dave.hansen@intel.com
Cc: arjan@linux.intel.com
Cc: torvalds@linux-foundation.org
Cc: peterz@infradead.org
Cc: bp@alien8.de
Cc: pbonzini@redhat.com
Cc: tim.c.chen@linux.intel.com
Cc: gregkh@linux-foundation.org
Link: https://lkml.kernel.org/r/1516896855-7642-8-git-send-email-dwmw@amazon.co.uk
6 years agox86/cpufeature: Blacklist SPEC_CTRL/PRED_CMD on early Spectre v2 microcodes
David Woodhouse [Thu, 25 Jan 2018 16:14:14 +0000 (16:14 +0000)]
x86/cpufeature: Blacklist SPEC_CTRL/PRED_CMD on early Spectre v2 microcodes

This doesn't refuse to load the affected microcodes; it just refuses to
use the Spectre v2 mitigation features if they're detected, by clearing
the appropriate feature bits.

The AMD CPUID bits are handled here too, because hypervisors *may* have
been exposing those bits even on Intel chips, for fine-grained control
of what's available.

It is non-trivial to use x86_match_cpu() for this table because that
doesn't handle steppings. And the approach taken in commit bd9240a18
almost made me lose my lunch.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: ak@linux.intel.com
Cc: ashok.raj@intel.com
Cc: dave.hansen@intel.com
Cc: karahmed@amazon.de
Cc: arjan@linux.intel.com
Cc: torvalds@linux-foundation.org
Cc: peterz@infradead.org
Cc: bp@alien8.de
Cc: pbonzini@redhat.com
Cc: tim.c.chen@linux.intel.com
Cc: gregkh@linux-foundation.org
Link: https://lkml.kernel.org/r/1516896855-7642-7-git-send-email-dwmw@amazon.co.uk
6 years agox86/pti: Do not enable PTI on CPUs which are not vulnerable to Meltdown
David Woodhouse [Thu, 25 Jan 2018 16:14:13 +0000 (16:14 +0000)]
x86/pti: Do not enable PTI on CPUs which are not vulnerable to Meltdown

Also, for CPUs which don't speculate at all, don't report that they're
vulnerable to the Spectre variants either.

Leave the cpu_no_meltdown[] match table with just X86_VENDOR_AMD in it
for now, even though that could be done with a simple comparison, on the
assumption that we'll have more to add.

Based on suggestions from Dave Hansen and Alan Cox.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: ak@linux.intel.com
Cc: ashok.raj@intel.com
Cc: karahmed@amazon.de
Cc: arjan@linux.intel.com
Cc: torvalds@linux-foundation.org
Cc: peterz@infradead.org
Cc: bp@alien8.de
Cc: pbonzini@redhat.com
Cc: tim.c.chen@linux.intel.com
Cc: gregkh@linux-foundation.org
Link: https://lkml.kernel.org/r/1516896855-7642-6-git-send-email-dwmw@amazon.co.uk
6 years agox86/msr: Add definitions for new speculation control MSRs
David Woodhouse [Thu, 25 Jan 2018 16:14:12 +0000 (16:14 +0000)]
x86/msr: Add definitions for new speculation control MSRs

Add MSR and bit definitions for SPEC_CTRL, PRED_CMD and ARCH_CAPABILITIES.

See Intel's 336996-Speculative-Execution-Side-Channel-Mitigations.pdf

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: ak@linux.intel.com
Cc: ashok.raj@intel.com
Cc: dave.hansen@intel.com
Cc: karahmed@amazon.de
Cc: arjan@linux.intel.com
Cc: torvalds@linux-foundation.org
Cc: peterz@infradead.org
Cc: bp@alien8.de
Cc: pbonzini@redhat.com
Cc: tim.c.chen@linux.intel.com
Cc: gregkh@linux-foundation.org
Link: https://lkml.kernel.org/r/1516896855-7642-5-git-send-email-dwmw@amazon.co.uk
6 years agox86/cpufeatures: Add AMD feature bits for Speculation Control
David Woodhouse [Thu, 25 Jan 2018 16:14:11 +0000 (16:14 +0000)]
x86/cpufeatures: Add AMD feature bits for Speculation Control

AMD exposes the PRED_CMD/SPEC_CTRL MSRs slightly differently to Intel.
See http://lkml.kernel.org/r/2b3e25cc-286d-8bd0-aeaf-9ac4aae39de8@amd.com

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: ak@linux.intel.com
Cc: ashok.raj@intel.com
Cc: dave.hansen@intel.com
Cc: karahmed@amazon.de
Cc: arjan@linux.intel.com
Cc: torvalds@linux-foundation.org
Cc: peterz@infradead.org
Cc: bp@alien8.de
Cc: pbonzini@redhat.com
Cc: tim.c.chen@linux.intel.com
Cc: gregkh@linux-foundation.org
Link: https://lkml.kernel.org/r/1516896855-7642-4-git-send-email-dwmw@amazon.co.uk
6 years agox86/cpufeatures: Add Intel feature bits for Speculation Control
David Woodhouse [Thu, 25 Jan 2018 16:14:10 +0000 (16:14 +0000)]
x86/cpufeatures: Add Intel feature bits for Speculation Control

Add three feature bits exposed by new microcode on Intel CPUs for
speculation control.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: ak@linux.intel.com
Cc: ashok.raj@intel.com
Cc: dave.hansen@intel.com
Cc: karahmed@amazon.de
Cc: arjan@linux.intel.com
Cc: torvalds@linux-foundation.org
Cc: peterz@infradead.org
Cc: bp@alien8.de
Cc: pbonzini@redhat.com
Cc: tim.c.chen@linux.intel.com
Cc: gregkh@linux-foundation.org
Link: https://lkml.kernel.org/r/1516896855-7642-3-git-send-email-dwmw@amazon.co.uk
6 years agox86/cpufeatures: Add CPUID_7_EDX CPUID leaf
David Woodhouse [Thu, 25 Jan 2018 16:14:09 +0000 (16:14 +0000)]
x86/cpufeatures: Add CPUID_7_EDX CPUID leaf

This is a pure feature bits leaf. There are two AVX512 feature bits in it
already which were handled as scattered bits, and three more from this leaf
are going to be added for speculation control features.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: ak@linux.intel.com
Cc: ashok.raj@intel.com
Cc: dave.hansen@intel.com
Cc: karahmed@amazon.de
Cc: arjan@linux.intel.com
Cc: torvalds@linux-foundation.org
Cc: peterz@infradead.org
Cc: bp@alien8.de
Cc: pbonzini@redhat.com
Cc: tim.c.chen@linux.intel.com
Cc: gregkh@linux-foundation.org
Link: https://lkml.kernel.org/r/1516896855-7642-2-git-send-email-dwmw@amazon.co.uk
6 years agomodule/retpoline: Warn about missing retpoline in module
Andi Kleen [Thu, 25 Jan 2018 23:50:28 +0000 (15:50 -0800)]
module/retpoline: Warn about missing retpoline in module

There's a risk that a kernel which has full retpoline mitigations becomes
vulnerable when a module gets loaded that hasn't been compiled with the
right compiler or the right option.

To enable detection of that mismatch at module load time, add a module info
string "retpoline" at build time when the module was compiled with
retpoline support. This only covers compiled C source, but assembler source
or prebuilt object files are not checked.

If a retpoline enabled kernel detects a non retpoline protected module at
load time, print a warning and report it in the sysfs vulnerability file.

[ tglx: Massaged changelog ]

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: gregkh@linuxfoundation.org
Cc: torvalds@linux-foundation.org
Cc: jeyu@kernel.org
Cc: arjan@linux.intel.com
Link: https://lkml.kernel.org/r/20180125235028.31211-1-andi@firstfloor.org
6 years agoMerge branch 'linux-4.15' of git://github.com/skeggsb/linux into drm-fixes
Dave Airlie [Fri, 26 Jan 2018 05:27:07 +0000 (15:27 +1000)]
Merge branch 'linux-4.15' of git://github.com/skeggsb/linux into drm-fixes

Single irq regression fix
* 'linux-4.15' of git://github.com/skeggsb/linux:
  drm/nouveau: Move irq setup/teardown to pci ctor/dtor

6 years agonet: vrf: Add support for sends to local broadcast address
David Ahern [Thu, 25 Jan 2018 03:37:37 +0000 (19:37 -0800)]
net: vrf: Add support for sends to local broadcast address

Sukumar reported that sends to the local broadcast address
(255.255.255.255) are broken. Check for the address in vrf driver
and do not redirect to the VRF device - similar to multicast
packets.

With this change sockets can use SO_BINDTODEVICE to specify an
egress interface and receive responses. Note: the egress interface
can not be a VRF device but needs to be the enslaved device.

https://bugzilla.kernel.org/show_bug.cgi?id=198521

Reported-by: Sukumar Gopalakrishnan <sukumarg1973@gmail.com>
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agor8169: fix memory corruption on retrieval of hardware statistics.
Francois Romieu [Fri, 26 Jan 2018 00:53:26 +0000 (01:53 +0100)]
r8169: fix memory corruption on retrieval of hardware statistics.

Hardware statistics retrieval hurts in tight invocation loops.

Avoid extraneous write and enforce strict ordering of writes targeted to
the tally counters dump area address registers.

Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Tested-by: Oliver Freyermuth <o.freyermuth@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agoMerge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Linus Torvalds [Fri, 26 Jan 2018 01:30:47 +0000 (17:30 -0800)]
Merge branch 'for-linus' of git://git./linux/kernel/git/dtor/input

Pull input fixes from Dmitry Torokhov:
 "The main item is that we try to better handle the newer trackpoints on
  Lenovo devices that are now being produced by Elan/ALPS/NXP and only
  implement a small subset of the original IBM trackpoint controls"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Revert "Input: synaptics_rmi4 - use devm_device_add_group() for attributes in F01"
  Input: trackpoint - only expose supported controls for Elan, ALPS and NXP
  Input: trackpoint - force 3 buttons if 0 button is reported
  Input: xpad - add support for PDP Xbox One controllers
  Input: stmfts,s6sy671 - add SPDX identifier

6 years agoorangefs: fix deadlock; do not write i_size in read_iter
Martin Brandenburg [Fri, 26 Jan 2018 00:39:44 +0000 (19:39 -0500)]
orangefs: fix deadlock; do not write i_size in read_iter

After do_readv_writev, the inode cache is invalidated anyway, so i_size
will never be read.  It will be fetched from the server which will also
know about updates from other machines.

Fixes deadlock on 32-bit SMP.

See https://marc.info/?l=linux-fsdevel&m=151268557427760&w=2

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Mike Marshall <hubcap@omnibond.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agodrm/nouveau: Move irq setup/teardown to pci ctor/dtor
Lyude Paul [Thu, 25 Jan 2018 23:29:53 +0000 (18:29 -0500)]
drm/nouveau: Move irq setup/teardown to pci ctor/dtor

For a while we've been having issues with seemingly random interrupts
coming from nvidia cards when resuming them. Originally the fix for this
was thought to be just re-arming the MSI interrupt registers right after
re-allocating our IRQs, however it seems a lot of what we do is both
wrong and not even nessecary.

This was made apparent by what appeared to be a regression in the
mainline kernel that started introducing suspend/resume issues for
nouveau:

        a0c9259dc4e1 (irq/matrix: Spread interrupts on allocation)

After this commit was introduced, we started getting interrupts from the
GPU before we actually re-allocated our own IRQ (see references below)
and assigned the IRQ handler. Investigating this turned out that the
problem was not with the commit, but the fact that nouveau even
free/allocates it's irqs before and after suspend/resume.

For starters: drivers in the linux kernel haven't had to handle
freeing/re-allocating their IRQs during suspend/resume cycles for quite
a while now. Nouveau seems to be one of the few drivers left that still
does this, despite the fact there's no reason we actually need to since
disabling interrupts from the device side should be enough, as the
kernel is already smart enough to know to disable host-side interrupts
for us before going into suspend. Since we were tearing down our IRQs by
hand however, that means there was a short period during resume where
interrupts could be received before we re-allocated our IRQ which would
lead to us getting an unhandled IRQ. Since we never handle said IRQ and
re-arm the interrupt registers, this would cause us to miss all of the
interrupts from the GPU and cause our init process to start timing out
on anything requiring interrupts.

So, since this whole setup/teardown every suspend/resume cycle is
useless anyway, move irq setup/teardown into the pci subdev's ctor/dtor
functions instead so they're only called at driver load and driver
unload. This should fix most of the issues with pending interrupts on
resume, along with getting suspend/resume for nouveau to work again.

As well, this probably means we can also just remove the msi rearm call
inside nvkm_pci_init(). But since our main focus here is to fix
suspend/resume before 4.15, we'll save that for a later patch.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Cc: Karol Herbst <kherbst@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Mike Galbraith <efault@gmx.de>
Cc: stable@vger.kernel.org
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
6 years agonet: don't call update_pmtu unconditionally
Nicolas Dichtel [Thu, 25 Jan 2018 18:03:03 +0000 (19:03 +0100)]
net: don't call update_pmtu unconditionally

Some dst_ops (e.g. md_dst_ops)) doesn't set this handler. It may result to:
"BUG: unable to handle kernel NULL pointer dereference at           (null)"

Let's add a helper to check if update_pmtu is available before calling it.

Fixes: 52a589d51f10 ("geneve: update skb dst pmtu on tx path")
Fixes: a93bf0ff4490 ("vxlan: update skb dst pmtu on tx path")
CC: Roman Kapl <code@rkapl.cz>
CC: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agoMerge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Linus Torvalds [Thu, 25 Jan 2018 17:32:10 +0000 (09:32 -0800)]
Merge tag 'for-linus' of git://git./virt/kvm/kvm

Pull KVM fixes from Radim Krčmář:
 "Fix races and a potential use after free in the s390 cmma migration
  code"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: s390: add proper locking for CMMA migration bitmap

6 years agoMerge tag 'for-4.15-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Linus Torvalds [Thu, 25 Jan 2018 17:03:10 +0000 (09:03 -0800)]
Merge tag 'for-4.15-tag' of git://git./linux/kernel/git/kdave/linux

Pull btrfs fix from David Sterba:
 "It's been reported recently that readdir can list stale entries under
  some conditions. Fix it."

* tag 'for-4.15-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  Btrfs: fix stale entries in readdir

6 years agonet: tcp: close sock if net namespace is exiting
Dan Streetman [Thu, 18 Jan 2018 21:14:26 +0000 (16:14 -0500)]
net: tcp: close sock if net namespace is exiting

When a tcp socket is closed, if it detects that its net namespace is
exiting, close immediately and do not wait for FIN sequence.

For normal sockets, a reference is taken to their net namespace, so it will
never exit while the socket is open.  However, kernel sockets do not take a
reference to their net namespace, so it may begin exiting while the kernel
socket is still open.  In this case if the kernel socket is a tcp socket,
it will stay open trying to complete its close sequence.  The sock's dst(s)
hold a reference to their interface, which are all transferred to the
namespace's loopback interface when the real interfaces are taken down.
When the namespace tries to take down its loopback interface, it hangs
waiting for all references to the loopback interface to release, which
results in messages like:

unregister_netdevice: waiting for lo to become free. Usage count = 1

These messages continue until the socket finally times out and closes.
Since the net namespace cleanup holds the net_mutex while calling its
registered pernet callbacks, any new net namespace initialization is
blocked until the current net namespace finishes exiting.

After this change, the tcp socket notices the exiting net namespace, and
closes immediately, releasing its dst(s) and their reference to the
loopback interface, which lets the net namespace continue exiting.

Link: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1711407
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=97811
Signed-off-by: Dan Streetman <ddstreet@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agoperf/x86: Fix perf,x86,cpuhp deadlock
Peter Zijlstra [Wed, 10 Jan 2018 18:23:08 +0000 (19:23 +0100)]
perf/x86: Fix perf,x86,cpuhp deadlock

More lockdep gifts, a 5-way lockup race:

perf_event_create_kernel_counter()
  perf_event_alloc()
    perf_try_init_event()
      x86_pmu_event_init()
__x86_pmu_event_init()
  x86_reserve_hardware()
 #0     mutex_lock(&pmc_reserve_mutex);
    reserve_ds_buffer()
 #1       get_online_cpus()

perf_event_release_kernel()
  _free_event()
    hw_perf_event_destroy()
      x86_release_hardware()
 #0 mutex_lock(&pmc_reserve_mutex)
release_ds_buffer()
 #1   get_online_cpus()

 #1 do_cpu_up()
  perf_event_init_cpu()
 #2     mutex_lock(&pmus_lock)
 #3     mutex_lock(&ctx->mutex)

sys_perf_event_open()
  mutex_lock_double()
 #3     mutex_lock(ctx->mutex)
 #4     mutex_lock_nested(ctx->mutex, 1);

perf_try_init_event()
 #4   mutex_lock_nested(ctx->mutex, 1)
  x86_pmu_event_init()
    intel_pmu_hw_config()
      x86_add_exclusive()
 #0 mutex_lock(&pmc_reserve_mutex)

Fix it by using ordering constructs instead of locking.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
6 years agoperf/core: Fix ctx::mutex deadlock
Peter Zijlstra [Tue, 9 Jan 2018 20:23:02 +0000 (21:23 +0100)]
perf/core: Fix ctx::mutex deadlock

Lockdep noticed the following 3-way lockup scenario:

sys_perf_event_open()
  perf_event_alloc()
    perf_try_init_event()
 #0       ctx = perf_event_ctx_lock_nested(1)
      perf_swevent_init()
swevent_hlist_get()
 #1   mutex_lock(&pmus_lock)

perf_event_init_cpu()
 #1   mutex_lock(&pmus_lock)
 #2   mutex_lock(&ctx->mutex)

sys_perf_event_open()
  mutex_lock_double()
 #2    mutex_lock()
 #0    mutex_lock_nested()

And while we need that perf_event_ctx_lock_nested() for HW PMUs such
that they can iterate the sibling list, trying to match it to the
available counters, the software PMUs need do no such thing. Exclude
them.

In particular the swevent triggers the above invertion, while the
tpevent PMU triggers a more elaborate one through their event_mutex.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
6 years agoperf/core: Fix another perf,trace,cpuhp lock inversion
Peter Zijlstra [Tue, 9 Jan 2018 16:07:59 +0000 (17:07 +0100)]
perf/core: Fix another perf,trace,cpuhp lock inversion

Lockdep noticed the following 3-way lockup race:

        perf_trace_init()
 #0       mutex_lock(&event_mutex)
          perf_trace_event_init()
            perf_trace_event_reg()
              tp_event->class->reg() := tracepoint_probe_register
 #1              mutex_lock(&tracepoints_mutex)
                  trace_point_add_func()
 #2                  static_key_enable()

 #2 do_cpu_up()
  perf_event_init_cpu()
 #3     mutex_lock(&pmus_lock)
 #4     mutex_lock(&ctx->mutex)

perf_ioctl()
 #4   ctx = perf_event_ctx_lock()
  _perf_iotcl()
    ftrace_profile_set_filter()
 #0       mutex_lock(&event_mutex)

Fudge it for now by noting that the tracepoint state does not depend
on the event <-> context relation. Ugly though :/

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
6 years agoperf/core: Fix lock inversion between perf,trace,cpuhp
Peter Zijlstra [Tue, 9 Jan 2018 12:10:30 +0000 (13:10 +0100)]
perf/core: Fix lock inversion between perf,trace,cpuhp

Lockdep gifted us with noticing the following 4-way lockup scenario:

        perf_trace_init()
 #0       mutex_lock(&event_mutex)
          perf_trace_event_init()
            perf_trace_event_reg()
              tp_event->class->reg() := tracepoint_probe_register
 #1             mutex_lock(&tracepoints_mutex)
                  trace_point_add_func()
 #2                 static_key_enable()

 #2     do_cpu_up()
          perf_event_init_cpu()
 #3         mutex_lock(&pmus_lock)
 #4         mutex_lock(&ctx->mutex)

        perf_event_task_disable()
          mutex_lock(&current->perf_event_mutex)
 #4       ctx = perf_event_ctx_lock()
 #5       perf_event_for_each_child()

        do_exit()
          task_work_run()
            __fput()
              perf_release()
                perf_event_release_kernel()
 #4               mutex_lock(&ctx->mutex)
 #5               mutex_lock(&event->child_mutex)
                  free_event()
                    _free_event()
                      event->destroy() := perf_trace_destroy
 #0                     mutex_lock(&event_mutex);

Fix that by moving the free_event() out from under the locks.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
6 years agoKVM: VMX: Make indirect call speculation safe
Peter Zijlstra [Thu, 25 Jan 2018 09:58:14 +0000 (10:58 +0100)]
KVM: VMX: Make indirect call speculation safe

Replace indirect call with CALL_NOSPEC.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Jun Nakajima <jun.nakajima@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: rga@amazon.de
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Link: https://lkml.kernel.org/r/20180125095843.645776917@infradead.org
6 years agoKVM: x86: Make indirect calls in emulator speculation safe
Peter Zijlstra [Thu, 25 Jan 2018 09:58:13 +0000 (10:58 +0100)]
KVM: x86: Make indirect calls in emulator speculation safe

Replace the indirect calls with CALL_NOSPEC.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Jun Nakajima <jun.nakajima@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: rga@amazon.de
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Link: https://lkml.kernel.org/r/20180125095843.595615683@infradead.org
6 years agoMerge tag 'drm-misc-fixes-2018-01-24' of git://anongit.freedesktop.org/drm/drm-misc...
Dave Airlie [Thu, 25 Jan 2018 02:28:15 +0000 (12:28 +1000)]
Merge tag 'drm-misc-fixes-2018-01-24' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes

Two vc4 fixes that were applied in the last day.
One fixes a NULL dereference, and the other fixes
a flickering bug.

Cc: Eric Anholt <eric@anholt.net>
Cc: Boris Brezillon <boris.brezillon@free-electrons.com>
* tag 'drm-misc-fixes-2018-01-24' of git://anongit.freedesktop.org/drm/drm-misc:
  drm/vc4: Fix NULL pointer dereference in vc4_save_hang_state()
  drm/vc4: Flush the caches before the bin jobs, as well.

6 years agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Linus Torvalds [Thu, 25 Jan 2018 01:24:30 +0000 (17:24 -0800)]
Merge git://git./linux/kernel/git/davem/net

Pull networking fixes from David Miller:

 1) Avoid negative netdev refcount in error flow of xfrm state add, from
    Aviad Yehezkel.

 2) Fix tcpdump decoding of IPSEC decap'd frames by filling in the
    ethernet header protocol field in xfrm{4,6}_mode_tunnel_input().
    From Yossi Kuperman.

 3) Fix a syzbot triggered skb_under_panic in pppoe having to do with
    failing to allocate an appropriate amount of headroom. From
    Guillaume Nault.

 4) Fix memory leak in vmxnet3 driver, from Neil Horman.

 5) Cure out-of-bounds packet memory access in em_nbyte EMATCH module,
    from Wolfgang Bumiller.

 6) Restrict what kinds of sockets can be bound to the KCM multiplexer
    and also disallow when another layer has attached to the socket and
    made use of sk_user_data. From Tom Herbert.

 7) Fix use before init of IOTLB in vhost code, from Jason Wang.

 8) Correct STACR register write bit definition in IBM emac driver, from
    Ivan Mikhaylov.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  net/ibm/emac: wrong bit is used for STA control register write
  net/ibm/emac: add 8192 rx/tx fifo size
  vhost: do not try to access device IOTLB when not initialized
  vhost: use mutex_lock_nested() in vhost_dev_lock_vqs()
  i40e: flower: check if TC offload is enabled on a netdev
  qed: Free reserved MR tid
  qed: Remove reserveration of dpi for kernel
  kcm: Check if sk_user_data already set in kcm_attach
  kcm: Only allow TCP sockets to be attached to a KCM mux
  net: sched: fix TCF_LAYER_LINK case in tcf_get_base_ptr
  net: sched: em_nbyte: don't add the data offset twice
  mlxsw: spectrum_router: Don't log an error on missing neighbor
  vmxnet3: repair memory leak
  ipv6: Fix getsockopt() for sockets with default IPV6_AUTOFLOWLABEL
  pppoe: take ->needed_headroom of lower device into account on xmit
  xfrm: fix boolean assignment in xfrm_get_type_offload
  xfrm: Fix eth_hdr(skb)->h_proto to reflect inner IP version
  xfrm: fix error flow in case of add state fails
  xfrm: Add SA to hardware at the end of xfrm_state_construct()

6 years agoMerge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc
Linus Torvalds [Wed, 24 Jan 2018 23:49:02 +0000 (15:49 -0800)]
Merge git://git./linux/kernel/git/davem/sparc

Pull sparc bugfix from David Miller:
 "Sparc Makefile typo fix"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc64: fix typo in CONFIG_CRYPTO_DES_SPARC64 => CONFIG_CRYPTO_CAMELLIA_SPARC64

6 years agonet/ibm/emac: wrong bit is used for STA control register write
Ivan Mikhaylov [Wed, 24 Jan 2018 12:53:25 +0000 (15:53 +0300)]
net/ibm/emac: wrong bit is used for STA control register write

STA control register has areas of mode and opcodes for opeations. 18 bit is
using for mode selection, where 0 is old MIO/MDIO access method and 1 is
indirect access mode. 19-20 bits are using for setting up read/write
operation(STA opcodes). In current state 'read' is set into old MIO/MDIO mode
with 19 bit and write operation is set into 18 bit which is mode selection,
not a write operation. To correlate write with read we set it into 20 bit.
All those bit operations are MSB 0 based.

Signed-off-by: Ivan Mikhaylov <ivan@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agonet/ibm/emac: add 8192 rx/tx fifo size
Ivan Mikhaylov [Wed, 24 Jan 2018 12:53:24 +0000 (15:53 +0300)]
net/ibm/emac: add 8192 rx/tx fifo size

emac4syn chips has availability to use 8192 rx/tx fifo buffer sizes,
in current state if we set it up in dts 8192 as example, we will get
only 2048 which may impact on network speed.

Signed-off-by: Ivan Mikhaylov <ivan@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agoRevert "Input: synaptics_rmi4 - use devm_device_add_group() for attributes in F01"
Nick Dyer [Wed, 24 Jan 2018 21:46:04 +0000 (13:46 -0800)]
Revert "Input: synaptics_rmi4 - use devm_device_add_group() for attributes in F01"

Since the sysfs attribute hangs off the RMI bus, which doesn't go away during
firmware flash, it needs to be explicitly removed, otherwise we would try and
register the same attribute twice.

This reverts commit 36a44af5c176d619552d99697433261141dd1296.

Signed-off-by: Nick Dyer <nick@shmanahar.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
6 years agovhost: do not try to access device IOTLB when not initialized
Jason Wang [Tue, 23 Jan 2018 09:27:26 +0000 (17:27 +0800)]
vhost: do not try to access device IOTLB when not initialized

The code will try to access dev->iotlb when processing
VHOST_IOTLB_INVALIDATE even if it was not initialized which may lead
to NULL pointer dereference. Fixes this by check dev->iotlb before.

Fixes: 6b1e6cc7855b0 ("vhost: new device IOTLB API")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agovhost: use mutex_lock_nested() in vhost_dev_lock_vqs()
Jason Wang [Tue, 23 Jan 2018 09:27:25 +0000 (17:27 +0800)]
vhost: use mutex_lock_nested() in vhost_dev_lock_vqs()

We used to call mutex_lock() in vhost_dev_lock_vqs() which tries to
hold mutexes of all virtqueues. This may confuse lockdep to report a
possible deadlock because of trying to hold locks belong to same
class. Switch to use mutex_lock_nested() to avoid false positive.

Fixes: 6b1e6cc7855b0 ("vhost: new device IOTLB API")
Reported-by: syzbot+dbb7c1161485e61b0241@syzkaller.appspotmail.com
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agoi40e: flower: check if TC offload is enabled on a netdev
Jakub Kicinski [Tue, 23 Jan 2018 08:08:40 +0000 (00:08 -0800)]
i40e: flower: check if TC offload is enabled on a netdev

Since TC block changes drivers are required to check if
the TC hw offload flag is set on the interface themselves.

Fixes: 2f4b411a3d67 ("i40e: Enable cloud filters via tc-flower")
Fixes: 44ae12a768b7 ("net: sched: move the can_offload check from binding phase to rule insertion phase")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Amritha Nambiar <amritha.nambiar@intel.com>
Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agosparc64: fix typo in CONFIG_CRYPTO_DES_SPARC64 => CONFIG_CRYPTO_CAMELLIA_SPARC64
Corentin Labbe [Tue, 23 Jan 2018 14:33:14 +0000 (14:33 +0000)]
sparc64: fix typo in CONFIG_CRYPTO_DES_SPARC64 => CONFIG_CRYPTO_CAMELLIA_SPARC64

This patch fixes the typo CONFIG_CRYPTO_DES_SPARC64 => CONFIG_CRYPTO_CAMELLIA_SPARC64

Fixes: 81658ad0d923 ("sparc64: Add CAMELLIA driver making use of the new camellia opcodes.")
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agoMerge branch 'qed-rdma-bug-fixes'
David S. Miller [Wed, 24 Jan 2018 21:44:21 +0000 (16:44 -0500)]
Merge branch 'qed-rdma-bug-fixes'

Michal Kalderon says:

====================
qed: rdma bug fixes

This patch contains two small bug fixes related to RDMA.
Both related to resource reservations.
====================

Signed-off-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Signed-off-by: Ariel Elior <Ariel.Elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agoqed: Free reserved MR tid
Michal Kalderon [Tue, 23 Jan 2018 09:33:47 +0000 (11:33 +0200)]
qed: Free reserved MR tid

A tid was allocated for reserved MR during initialization but
not freed. This lead to an annoying output message during
rdma unload flow.

Signed-off-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Signed-off-by: Ariel Elior <Ariel.Elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agoqed: Remove reserveration of dpi for kernel
Michal Kalderon [Tue, 23 Jan 2018 09:33:46 +0000 (11:33 +0200)]
qed: Remove reserveration of dpi for kernel

Double reservation for kernel dedicated dpi was performed.
Once in the core module and once in qedr.
Remove the reservation from core.

Signed-off-by: Michal Kalderon <Michal.Kalderon@cavium.com>
Signed-off-by: Ariel Elior <Ariel.Elior@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agoMerge branch 'kcm-fix-two-syzcaller-issues'
David S. Miller [Wed, 24 Jan 2018 20:54:31 +0000 (15:54 -0500)]
Merge branch 'kcm-fix-two-syzcaller-issues'

Tom Herbert says:

====================
kcm: fix two syzcaller issues

In this patch set:

- Don't allow attaching non-TCP or listener sockets to a KCM mux.
- In kcm_attach Check if sk_user_data is already set. This is
  under lock to avoid race conditions. More work is need to make
  all of the users of sk_user_data to use the same locking.

- v2
  Remove unncessary check for not PF_KCM in kcm_attach (suggested by
  Guillaume Nault)
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agokcm: Check if sk_user_data already set in kcm_attach
Tom Herbert [Wed, 24 Jan 2018 20:35:41 +0000 (12:35 -0800)]
kcm: Check if sk_user_data already set in kcm_attach

This is needed to prevent sk_user_data being overwritten.
The check is done under the callback lock. This should prevent
a socket from being attached twice to a KCM mux. It also prevents
a socket from being attached for other use cases of sk_user_data
as long as the other cases set sk_user_data under the lock.
Followup work is needed to unify all the use cases of sk_user_data
to use the same locking.

Reported-by: syzbot+114b15f2be420a8886c3@syzkaller.appspotmail.com
Fixes: ab7ac4eb9832 ("kcm: Kernel Connection Multiplexor module")
Signed-off-by: Tom Herbert <tom@quantonium.net>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agokcm: Only allow TCP sockets to be attached to a KCM mux
Tom Herbert [Wed, 24 Jan 2018 20:35:40 +0000 (12:35 -0800)]
kcm: Only allow TCP sockets to be attached to a KCM mux

TCP sockets for IPv4 and IPv6 that are not listeners or in closed
stated are allowed to be attached to a KCM mux.

Fixes: ab7ac4eb9832 ("kcm: Kernel Connection Multiplexor module")
Reported-by: syzbot+8865eaff7f9acd593945@syzkaller.appspotmail.com
Signed-off-by: Tom Herbert <tom@quantonium.net>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agoMAINTAINERS: update email address for James Morris
James Morris [Wed, 24 Jan 2018 20:53:57 +0000 (07:53 +1100)]
MAINTAINERS: update email address for James Morris

Update my email address.

Signed-off-by: James Morris <jmorris@namei.org>
6 years agonet: sched: fix TCF_LAYER_LINK case in tcf_get_base_ptr
Wolfgang Bumiller [Thu, 18 Jan 2018 10:32:36 +0000 (11:32 +0100)]
net: sched: fix TCF_LAYER_LINK case in tcf_get_base_ptr

TCF_LAYER_LINK and TCF_LAYER_NETWORK returned the same pointer as
skb->data points to the network header.
Use skb_mac_header instead.

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agonet: sched: em_nbyte: don't add the data offset twice
Wolfgang Bumiller [Thu, 18 Jan 2018 10:32:35 +0000 (11:32 +0100)]
net: sched: em_nbyte: don't add the data offset twice

'ptr' is shifted by the offset and then validated,
the memcmp should not add it a second time.

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agoBtrfs: fix stale entries in readdir
Josef Bacik [Tue, 23 Jan 2018 20:17:05 +0000 (15:17 -0500)]
Btrfs: fix stale entries in readdir

In fixing the readdir+pagefault deadlock I accidentally introduced a
stale entry regression in readdir.  If we get close to full for the
temporary buffer, and then skip a few delayed deletions, and then try to
add another entry that won't fit, we will emit the entries we found and
retry.  Unfortunately we delete entries from our del_list as we find
them, assuming we won't need them.  However our pos will be with
whatever our last entry was, which could be before the delayed deletions
we skipped, so the next search will add the deleted entries back into
our readdir buffer.  So instead don't delete entries we find in our
del_list so we can make sure we always find our delayed deletions.  This
is a slight perf hit for readdir with lots of pending deletions, but
hopefully this isn't a common occurrence.  If it is we can revist this
and optimize it.

cc: stable@vger.kernel.org
Fixes: 23b5ec74943f ("btrfs: fix readdir deadlock with pagefault")
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
6 years agoMerge tag 'trace-v4.15-rc9' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt...
Linus Torvalds [Wed, 24 Jan 2018 18:08:16 +0000 (10:08 -0800)]
Merge tag 'trace-v4.15-rc9' of git://git./linux/kernel/git/rostedt/linux-trace

Pull tracing fixes from Steven Rostedt:
 "With the new ORC unwinder, ftrace stack tracing became disfunctional.

  One was that ORC didn't know how to handle the ftrace callbacks in
  general (which Josh fixed).

  The other was that ORC would just bail if it hit a dynamically
  allocated trampoline. Which means all ftrace stack tracing that
  happens from the function tracer would produce no results (that
  includes killing the max stack size tracer). I added a check to the
  ORC unwinder to see if the trampoline belonged to ftrace, and if it
  did, use the orc entry of the static trampoline that was used to
  create the dynamic one (it would be identical).

  Finally, I noticed that the skip values of the stack tracing were out
  of whack. I went through and fixed them up"

* tag 'trace-v4.15-rc9' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Update stack trace skipping for ORC unwinder
  ftrace, orc, x86: Handle ftrace dynamically allocated trampolines
  x86/ftrace: Fix ORC unwinding from ftrace handlers

6 years agoMAINTAINERS: clarify that only verified bugs should be submitted to security@
Willy Tarreau [Thu, 4 Jan 2018 13:31:25 +0000 (14:31 +0100)]
MAINTAINERS: clarify that only verified bugs should be submitted to security@

We're seeing a raise of automated reports from testing tools and reports
about address leaks that are not really exploitable as-is, many of which
do not represent an immediate risk justifying to work in closed places.

Signed-off-by: Willy Tarreau <w@1wt.eu>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agoRevert "module: Add retpoline tag to VERMAGIC"
Greg Kroah-Hartman [Wed, 24 Jan 2018 14:28:17 +0000 (15:28 +0100)]
Revert "module: Add retpoline tag to VERMAGIC"

This reverts commit 6cfb521ac0d5b97470883ff9b7facae264b7ab12.

Turns out distros do not want to make retpoline as part of their "ABI",
so this patch should not have been merged.  Sorry Andi, this was my
fault, I suggested it when your original patch was the "correct" way of
doing this instead.

Reported-by: Jiri Kosina <jikos@kernel.org>
Fixes: 6cfb521ac0d5 ("module: Add retpoline tag to VERMAGIC")
Acked-by: Andi Kleen <ak@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: David Woodhouse <dwmw@amazon.co.uk>
Cc: rusty@rustcorp.com.au
Cc: arjan.van.de.ven@intel.com
Cc: jeyu@kernel.org
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
6 years agomlxsw: spectrum_router: Don't log an error on missing neighbor
Yuval Mintz [Wed, 24 Jan 2018 09:02:09 +0000 (10:02 +0100)]
mlxsw: spectrum_router: Don't log an error on missing neighbor

Driver periodically samples all neighbors configured in device
in order to update the kernel regarding their state. When finding
an entry configured in HW that doesn't show in neigh_lookup()
driver logs an error message.
This introduces a race when removing multiple neighbors -
it's possible that a given entry would still be configured in HW
as its removal is still being processed but is already removed
from the kernel's neighbor tables.

Simply remove the error message and gracefully accept such events.

Fixes: c723c735fa6b ("mlxsw: spectrum_router: Periodically update the kernel's neigh table")
Fixes: 60f040ca11b9 ("mlxsw: spectrum_router: Periodically dump active IPv6 neighbours")
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 agoMerge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec
David S. Miller [Wed, 24 Jan 2018 15:32:29 +0000 (10:32 -0500)]
Merge branch 'master' of git://git./linux/kernel/git/klassert/ipsec

Steffen Klassert says:

====================
pull request (net): ipsec 2018-01-24

1) Only offloads SAs after they are fully initialized.
   Otherwise a NIC may receive packets on a SA we can
   not yet handle in the stack.
   From Yossi Kuperman.

2) Fix negative refcount in case of a failing offload.
   From Aviad Yehezkel.

3) Fix inner IP ptoro version when decapsulating
   from interaddress family tunnels.
   From Yossi Kuperman.

4) Use true or false for boolean variables instead of an
   integer value in xfrm_get_type_offload.
   From Gustavo A. R. Silva.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
6 years agoMerge tag 'kvm-s390-master-4.15-3' of git://git.kernel.org/pub/scm/linux/kernel/git...
Radim Krčmář [Wed, 24 Jan 2018 15:25:53 +0000 (16:25 +0100)]
Merge tag 'kvm-s390-master-4.15-3' of git://git./linux/kernel/git/kvms390/linux

KVM: s390: another fix for cmma migration

This fixes races and potential use after free in the
cmma migration code.

6 years agoKVM: s390: add proper locking for CMMA migration bitmap
Christian Borntraeger [Fri, 22 Dec 2017 09:54:20 +0000 (10:54 +0100)]
KVM: s390: add proper locking for CMMA migration bitmap

Some parts of the cmma migration bitmap is already protected
with the kvm->lock (e.g. the migration start). On the other
hand the read of the cmma bits is not protected against a
concurrent free, neither is the emulation of the ESSA instruction.
Let's extend the locking to all related ioctls by using
the slots lock for
- kvm_s390_vm_start_migration
- kvm_s390_vm_stop_migration
- kvm_s390_set_cmma_bits
- kvm_s390_get_cmma_bits

In addition to that, we use synchronize_srcu before freeing
the migration structure as all users hold kvm->srcu for read.
(e.g. the ESSA handler).

Reported-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: stable@vger.kernel.org # 4.13+
Fixes: 190df4a212a7 (KVM: s390: CMMA tracking, ESSA emulation, migration mode)
Reviewed-by: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
6 years agox86/microcode: Fix again accessing initrd after having been freed
Borislav Petkov [Tue, 23 Jan 2018 10:41:33 +0000 (11:41 +0100)]
x86/microcode: Fix again accessing initrd after having been freed

Commit 24c2503255d3 ("x86/microcode: Do not access the initrd after it has
been freed") fixed attempts to access initrd from the microcode loader
after it has been freed. However, a similar KASAN warning was reported
(stack trace edited):

  smpboot: Booting Node 0 Processor 1 APIC 0x11
  ==================================================================
  BUG: KASAN: use-after-free in find_cpio_data+0x9b5/0xa50
  Read of size 1 at addr ffff880035ffd000 by task swapper/1/0

  CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.14.8-slack #7
  Hardware name: System manufacturer System Product Name/A88X-PLUS, BIOS 3003 03/10/2016
  Call Trace:
   dump_stack
   print_address_description
   kasan_report
   ? find_cpio_data
   __asan_report_load1_noabort
   find_cpio_data
   find_microcode_in_initrd
   __load_ucode_amd
   load_ucode_amd_ap
      load_ucode_ap

After some investigation, it turned out that a merge was done using the
wrong side to resolve, leading to picking up the previous state, before
the 24c2503255d3 fix. Therefore the Fixes tag below contains a merge
commit.

Revert the mismerge by catching the save_microcode_in_initrd_amd()
retval and thus letting the function exit with the last return statement
so that initrd_gone can be set to true.

Fixes: f26483eaedec ("Merge branch 'x86/urgent' into x86/microcode, to resolve conflicts")
Reported-by: <higuita@gmx.net>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://bugzilla.kernel.org/show_bug.cgi?id=198295
Link: https://lkml.kernel.org/r/20180123104133.918-2-bp@alien8.de
6 years agox86/microcode/intel: Extend BDW late-loading further with LLC size check
Jia Zhang [Tue, 23 Jan 2018 10:41:32 +0000 (11:41 +0100)]
x86/microcode/intel: Extend BDW late-loading further with LLC size check

Commit b94b73733171 ("x86/microcode/intel: Extend BDW late-loading with a
revision check") reduced the impact of erratum BDF90 for Broadwell model
79.

The impact can be reduced further by checking the size of the last level
cache portion per core.

Tony: "The erratum says the problem only occurs on the large-cache SKUs.
So we only need to avoid the update if we are on a big cache SKU that is
also running old microcode."

For more details, see erratum BDF90 in document #334165 (Intel Xeon
Processor E7-8800/4800 v4 Product Family Specification Update) from
September 2017.

Fixes: b94b73733171 ("x86/microcode/intel: Extend BDW late-loading with a revision check")
Signed-off-by: Jia Zhang <zhang.jia@linux.alibaba.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Tony Luck <tony.luck@intel.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1516321542-31161-1-git-send-email-zhang.jia@linux.alibaba.com
6 years agoperf/x86/amd/power: Do not load AMD power module on !AMD platforms
Xiao Liang [Mon, 22 Jan 2018 06:12:52 +0000 (14:12 +0800)]
perf/x86/amd/power: Do not load AMD power module on !AMD platforms

The AMD power module can be loaded on non AMD platforms, but unload fails
with the following Oops:

 BUG: unable to handle kernel NULL pointer dereference at           (null)
 IP: __list_del_entry_valid+0x29/0x90
 Call Trace:
  perf_pmu_unregister+0x25/0xf0
  amd_power_pmu_exit+0x1c/0xd23 [power]
  SyS_delete_module+0x1a8/0x2b0
  ? exit_to_usermode_loop+0x8f/0xb0
  entry_SYSCALL_64_fastpath+0x20/0x83

Return -ENODEV instead of 0 from the module init function if the CPU does
not match.

Fixes: c7ab62bfbe0e ("perf/x86/amd/power: Add AMD accumulated power reporting mechanism")
Signed-off-by: Xiao Liang <xiliang@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20180122061252.6394-1-xiliang@redhat.com
6 years agox86/retpoline: Remove the esp/rsp thunk
Waiman Long [Mon, 22 Jan 2018 22:09:34 +0000 (17:09 -0500)]
x86/retpoline: Remove the esp/rsp thunk

It doesn't make sense to have an indirect call thunk with esp/rsp as
retpoline code won't work correctly with the stack pointer register.
Removing it will help compiler writers to catch error in case such
a thunk call is emitted incorrectly.

Fixes: 76b043848fd2 ("x86/retpoline: Add initial retpoline support")
Suggested-by: Jeff Law <law@redhat.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: David Woodhouse <dwmw@amazon.co.uk>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Kees Cook <keescook@google.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Tim Chen <tim.c.chen@linux.intel.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: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: https://lkml.kernel.org/r/1516658974-27852-1-git-send-email-longman@redhat.com
6 years agosched/core: Fix cpu.max vs. cpuhotplug deadlock
Peter Zijlstra [Mon, 22 Jan 2018 21:53:28 +0000 (22:53 +0100)]
sched/core: Fix cpu.max vs. cpuhotplug deadlock

Tejun reported the following cpu-hotplug lock (percpu-rwsem) read recursion:

  tg_set_cfs_bandwidth()
    get_online_cpus()
      cpus_read_lock()

    cfs_bandwidth_usage_inc()
      static_key_slow_inc()
        cpus_read_lock()

Reported-by: Tejun Heo <tj@kernel.org>
Tested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180122215328.GP3397@worktop
Signed-off-by: Ingo Molnar <mingo@kernel.org>
6 years agolocking/lockdep: Avoid triggering hardlockup from debug_show_all_locks()
Tejun Heo [Mon, 22 Jan 2018 22:00:55 +0000 (14:00 -0800)]
locking/lockdep: Avoid triggering hardlockup from debug_show_all_locks()

debug_show_all_locks() iterates all tasks and print held locks whole
holding tasklist_lock.  This can take a while on a slow console device
and may end up triggering NMI hardlockup detector if someone else ends
up waiting for tasklist_lock.

Touch the NMI watchdog while printing the held locks to avoid
spuriously triggering the hardlockup detector.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel-team@fb.com
Link: http://lkml.kernel.org/r/20180122220055.GB1771050@devbig577.frc2.facebook.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
6 years agofutex: Fix OWNER_DEAD fixup
Peter Zijlstra [Mon, 22 Jan 2018 10:39:47 +0000 (11:39 +0100)]
futex: Fix OWNER_DEAD fixup

Both Geert and DaveJ reported that the recent futex commit:

  c1e2f0eaf015 ("futex: Avoid violating the 10th rule of futex")

introduced a problem with setting OWNER_DEAD. We set the bit on an
uninitialized variable and then entirely optimize it away as a
dead-store.

Move the setting of the bit to where it is more useful.

Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reported-by: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: c1e2f0eaf015 ("futex: Avoid violating the 10th rule of futex")
Link: http://lkml.kernel.org/r/20180122103947.GD2228@hirez.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>