linux-stable.git/include, branch v4.9.83

x86: fix build warnign with 32-bit PAE

2018-02-22T14:43:55+00:00

I ran into a 4.9 build warning in randconfig testing, starting with the
KAISER patches:

arch/x86/kernel/ldt.c: In function 'alloc_ldt_struct':
arch/x86/include/asm/pgtable_types.h:208:24: error: large integer implicitly truncated to unsigned type [-Werror=overflow]
 #define __PAGE_KERNEL  (__PAGE_KERNEL_EXEC | _PAGE_NX)
                        ^
arch/x86/kernel/ldt.c:81:6: note: in expansion of macro '__PAGE_KERNEL'
      __PAGE_KERNEL);
      ^~~~~~~~~~~~~

I originally ran into this last year when the patches were part of linux-next,
and tried to work around it by using the proper 'pteval_t' types consistently,
but that caused additional problems.

This takes a much simpler approach, and makes the argument type of the dummy
helper always 64-bit, which is wide enough for any page table layout and
won't hurt since this call is just an empty stub anyway.

Fixes: 8f0baadf2bea ("kaiser: merged update")
Signed-off-by: Arnd Bergmann 
Acked-by: Kees Cook 
Acked-by: Hugh Dickins 
Signed-off-by: Greg Kroah-Hartman

nospec: Move array_index_nospec() parameter checking into separate macro

2018-02-22T14:43:54+00:00

commit 8fa80c503b484ddc1abbd10c7cb2ab81f3824a50 upstream.

For architectures providing their own implementation of
array_index_mask_nospec() in asm/barrier.h, attempting to use WARN_ONCE() to
complain about out-of-range parameters using WARN_ON() results in a mess
of mutually-dependent include files.

Rather than unpick the dependencies, simply have the core code in nospec.h
perform the checking for us.

Signed-off-by: Will Deacon 
Acked-by: Thomas Gleixner 
Cc: Dan Williams 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1517840166-15399-1-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

compiler-gcc.h: Introduce __optimize function attribute

2018-02-22T14:43:53+00:00

commit df5d45aa08f848b79caf395211b222790534ccc7 upstream.

Create a new function attribute __optimize, which allows to specify an
optimization level on a per-function basis.

Signed-off-by: Geert Uytterhoeven 
Acked-by: Ard Biesheuvel 
Signed-off-by: Herbert Xu 
Signed-off-by: Greg Kroah-Hartman

jbd2: fix sphinx kernel-doc build warnings

2018-02-22T14:43:48+00:00

commit f69120ce6c024aa634a8fc25787205e42f0ccbe6 upstream.

Sphinx emits various (26) warnings when building make target 'htmldocs'.
Currently struct definitions contain duplicate documentation, some as
kernel-docs and some as standard c89 comments.  We can reduce
duplication while cleaning up the kernel docs.

Move all kernel-docs to right above each struct member.  Use the set of
all existing comments (kernel-doc and c89).  Add documentation for
missing struct members and function arguments.

Signed-off-by: Tobin C. Harding 
Signed-off-by: Theodore Ts'o 
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

crypto: poly1305 - remove ->setkey() method

2018-02-17T12:21:15+00:00

commit a16e772e664b9a261424107784804cffc8894977 upstream.

Since Poly1305 requires a nonce per invocation, the Linux kernel
implementations of Poly1305 don't use the crypto API's keying mechanism
and instead expect the key and nonce as the first 32 bytes of the data.
But ->setkey() is still defined as a stub returning an error code.  This
prevents Poly1305 from being used through AF_ALG and will also break it
completely once we start enforcing that all crypto API users (not just
AF_ALG) call ->setkey() if present.

Fix it by removing crypto_poly1305_setkey(), leaving ->setkey as NULL.

Signed-off-by: Eric Biggers 
Signed-off-by: Herbert Xu 
Signed-off-by: Greg Kroah-Hartman

crypto: hash - introduce crypto_hash_alg_has_setkey()

2018-02-17T12:21:15+00:00

commit cd6ed77ad5d223dc6299fb58f62e0f5267f7e2ba upstream.

Templates that use an shash spawn can use crypto_shash_alg_has_setkey()
to determine whether the underlying algorithm requires a key or not.
But there was no corresponding function for ahash spawns.  Add it.

Note that the new function actually has to support both shash and ahash
algorithms, since the ahash API can be used with either.

Signed-off-by: Eric Biggers 
Signed-off-by: Herbert Xu 
Signed-off-by: Greg Kroah-Hartman

mtd: cfi: convert inline functions to macros

2018-02-17T12:21:13+00:00

commit 9e343e87d2c4c707ef8fae2844864d4dde3a2d13 upstream.

The map_word_() functions, dating back to linux-2.6.8, try to perform
bitwise operations on a 'map_word' structure. This may have worked
with compilers that were current then (gcc-3.4 or earlier), but end
up being rather inefficient on any version I could try now (gcc-4.4 or
higher). Specifically we hit a problem analyzed in gcc PR81715 where we
fail to reuse the stack space for local variables.

This can be seen immediately in the stack consumption for
cfi_staa_erase_varsize() and other functions that (with CONFIG_KASAN)
can be up to 2200 bytes. Changing the inline functions into macros brings
this down to 1280 bytes.  Without KASAN, the same problem exists, but
the stack consumption is lower to start with, my patch shrinks it from
920 to 496 bytes on with arm-linux-gnueabi-gcc-5.4, and saves around
1KB in .text size for cfi_cmdset_0020.c, as it avoids copying map_word
structures for each call to one of these helpers.

With the latest gcc-8 snapshot, the problem is fixed in upstream gcc,
but nobody uses that yet, so we should still work around it in mainline
kernels and probably backport the workaround to stable kernels as well.
We had a couple of other functions that suffered from the same gcc bug,
and all of those had a simpler workaround involving dummy variables
in the inline function. Unfortunately that did not work here, the
macro hack was the best I could come up with.

It would also be helpful to have someone to a little performance testing
on the patch, to see how much it helps in terms of CPU utilitzation.

Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715
Signed-off-by: Arnd Bergmann 
Acked-by: Richard Weinberger 
Signed-off-by: Boris Brezillon 
Signed-off-by: Greg Kroah-Hartman

x86/retpoline: Avoid retpolines for built-in __init functions

2018-02-13T11:36:01+00:00

(cherry picked from commit 66f793099a636862a71c59d4a6ba91387b155e0c)

There's no point in building init code with retpolines, since it runs before
any potentially hostile userspace does. And before the retpoline is actually
ALTERNATIVEd into place, for much of it.

Signed-off-by: David Woodhouse 
Signed-off-by: Thomas Gleixner 
Cc: karahmed@amazon.de
Cc: peterz@infradead.org
Cc: bp@alien8.de
Link: https://lkml.kernel.org/r/1517484441-1420-2-git-send-email-dwmw@amazon.co.uk
Signed-off-by: David Woodhouse 
Signed-off-by: Greg Kroah-Hartman

vfs, fdtable: Prevent bounds-check bypass via speculative execution

2018-02-13T11:36:00+00:00

(cherry picked from commit 56c30ba7b348b90484969054d561f711ba196507)

'fd' is a user controlled value that is used as a data dependency to
read from the 'fdt->fd' array.  In order to avoid potential leaks of
kernel memory values, block speculative execution of the instruction
stream that could issue reads based on an invalid 'file *' returned from
__fcheck_files.

Co-developed-by: Elena Reshetova 
Signed-off-by: Dan Williams 
Signed-off-by: Thomas Gleixner 
Cc: linux-arch@vger.kernel.org
Cc: kernel-hardening@lists.openwall.com
Cc: gregkh@linuxfoundation.org
Cc: Al Viro 
Cc: torvalds@linux-foundation.org
Cc: alan@linux.intel.com
Link: https://lkml.kernel.org/r/151727418500.33451.17392199002892248656.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: David Woodhouse 
Signed-off-by: Greg Kroah-Hartman

array_index_nospec: Sanitize speculative array de-references

2018-02-13T11:35:59+00:00

(cherry picked from commit f3804203306e098dae9ca51540fcd5eb700d7f40)

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 
Co-developed-by: Alexei Starovoitov 
Suggested-by: Cyril Novikov 
Signed-off-by: Dan Williams 
Signed-off-by: Thomas Gleixner 
Cc: linux-arch@vger.kernel.org
Cc: kernel-hardening@lists.openwall.com
Cc: Peter Zijlstra 
Cc: Catalin Marinas 
Cc: Will Deacon 
Cc: Russell King 
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
Signed-off-by: David Woodhouse 
Signed-off-by: Greg Kroah-Hartman