linux-stable.git/arch, branch v3.10.71

MIPS: Export FP functions used by lose_fpu(1) for KVM

2015-03-06T22:40:54+00:00

commit 3ce465e04bfd8de9956d515d6e9587faac3375dc upstream.

Export the _save_fp asm function used by the lose_fpu(1) macro to GPL
modules so that KVM can make use of it when it is built as a module.

This fixes the following build error when CONFIG_KVM=m due to commit
f798217dfd03 ("KVM: MIPS: Don't leak FPU/DSP to guest"):

ERROR: "_save_fp" [arch/mips/kvm/kvm.ko] undefined!

Signed-off-by: James Hogan 
Fixes: f798217dfd03 (KVM: MIPS: Don't leak FPU/DSP to guest)
Cc: Paolo Bonzini 
Cc: Ralf Baechle 
Cc: Paul Burton 
Cc: Gleb Natapov 
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9260/
Signed-off-by: Ralf Baechle 
[james.hogan@imgtec.com: Only export when CPU_R4K_FPU=y prior to v3.16,
 so as not to break the Octeon build which excludes FPU support. KVM
 depends on MIPS32r2 anyway.]
Signed-off-by: James Hogan 
Signed-off-by: Greg Kroah-Hartman

x86, mm/ASLR: Fix stack randomization on 64-bit systems

2015-03-06T22:40:54+00:00

commit 4e7c22d447bb6d7e37bfe39ff658486ae78e8d77 upstream.

The issue is that the stack for processes is not properly randomized on
64 bit architectures due to an integer overflow.

The affected function is randomize_stack_top() in file
"fs/binfmt_elf.c":

  static unsigned long randomize_stack_top(unsigned long stack_top)
  {
           unsigned int random_variable = 0;

           if ((current->flags & PF_RANDOMIZE) &&
                   !(current->personality & ADDR_NO_RANDOMIZE)) {
                   random_variable = get_random_int() & STACK_RND_MASK;
                   random_variable <<= PAGE_SHIFT;
           }
           return PAGE_ALIGN(stack_top) + random_variable;
           return PAGE_ALIGN(stack_top) - random_variable;
  }

Note that, it declares the "random_variable" variable as "unsigned int".
Since the result of the shifting operation between STACK_RND_MASK (which
is 0x3fffff on x86_64, 22 bits) and PAGE_SHIFT (which is 12 on x86_64):

	  random_variable <<= PAGE_SHIFT;

then the two leftmost bits are dropped when storing the result in the
"random_variable". This variable shall be at least 34 bits long to hold
the (22+12) result.

These two dropped bits have an impact on the entropy of process stack.
Concretely, the total stack entropy is reduced by four: from 2^28 to
2^30 (One fourth of expected entropy).

This patch restores back the entropy by correcting the types involved
in the operations in the functions randomize_stack_top() and
stack_maxrandom_size().

The successful fix can be tested with:

  $ for i in `seq 1 10`; do cat /proc/self/maps | grep stack; done
  7ffeda566000-7ffeda587000 rw-p 00000000 00:00 0                          [stack]
  7fff5a332000-7fff5a353000 rw-p 00000000 00:00 0                          [stack]
  7ffcdb7a1000-7ffcdb7c2000 rw-p 00000000 00:00 0                          [stack]
  7ffd5e2c4000-7ffd5e2e5000 rw-p 00000000 00:00 0                          [stack]
  ...

Once corrected, the leading bytes should be between 7ffc and 7fff,
rather than always being 7fff.

Signed-off-by: Hector Marco-Gisbert 
Signed-off-by: Ismael Ripoll 
[ Rebased, fixed 80 char bugs, cleaned up commit message, added test example and CVE ]
Signed-off-by: Kees Cook 
Cc: Linus Torvalds 
Cc: Andrew Morton 
Cc: Al Viro 
Fixes: CVE-2015-1593
Link: http://lkml.kernel.org/r/20150214173350.GA18393@www.outflux.net
Signed-off-by: Borislav Petkov 
Signed-off-by: Greg Kroah-Hartman

metag: Fix KSTK_EIP() and KSTK_ESP() macros

2015-03-06T22:40:53+00:00

commit c2996cb29bfb73927a79dc96e598a718e843f01a upstream.

The KSTK_EIP() and KSTK_ESP() macros should return the user program
counter (PC) and stack pointer (A0StP) of the given task. These are used
to determine which VMA corresponds to the user stack in
/proc//maps, and for the user PC & A0StP in /proc//stat.

However for Meta the PC & A0StP from the task's kernel context are used,
resulting in broken output. For example in following /proc//maps
output, the 3afff000-3b021000 VMA should be described as the stack:

  # cat /proc/self/maps
  ...
  100b0000-100b1000 rwxp 00000000 00:00 0          [heap]
  3afff000-3b021000 rwxp 00000000 00:00 0

And in the following /proc//stat output, the PC is in kernel code
(1074234964 = 0x40078654) and the A0StP is in the kernel heap
(1335981392 = 0x4fa17550):

  # cat /proc/self/stat
  51 (cat) R ... 1335981392 1074234964 ...

Fix the definitions of KSTK_EIP() and KSTK_ESP() to use
task_pt_regs(tsk)->ctx rather than (tsk)->thread.kernel_context. This
gets the registers from the user context stored after the thread info at
the base of the kernel stack, which is from the last entry into the
kernel from userland, regardless of where in the kernel the task may
have been interrupted, which results in the following more correct
/proc//maps output:

  # cat /proc/self/maps
  ...
  0800b000-08070000 r-xp 00000000 00:02 207        /lib/libuClibc-0.9.34-git.so
  ...
  100b0000-100b1000 rwxp 00000000 00:00 0          [heap]
  3afff000-3b021000 rwxp 00000000 00:00 0          [stack]

And /proc//stat now correctly reports the PC in libuClibc
(134320308 = 0x80190b4) and the A0StP in the [stack] region (989864576 =
0x3b002280):

  # cat /proc/self/stat
  51 (cat) R ... 989864576 134320308 ...

Reported-by: Alexey Brodkin 
Reported-by: Vineet Gupta 
Signed-off-by: James Hogan 
Cc: linux-metag@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman

arm64: compat Fix siginfo_t -> compat_siginfo_t conversion on big endian

2015-03-06T22:40:52+00:00

commit 9d42d48a342aee208c1154696196497fdc556bbf upstream.

The native (64-bit) sigval_t union contains sival_int (32-bit) and
sival_ptr (64-bit). When a compat application invokes a syscall that
takes a sigval_t value (as part of a larger structure, e.g.
compat_sys_mq_notify, compat_sys_timer_create), the compat_sigval_t
union is converted to the native sigval_t with sival_int overlapping
with either the least or the most significant half of sival_ptr,
depending on endianness. When the corresponding signal is delivered to a
compat application, on big endian the current (compat_uptr_t)sival_ptr
cast always returns 0 since sival_int corresponds to the top part of
sival_ptr. This patch fixes copy_siginfo_to_user32() so that sival_int
is copied to the compat_siginfo_t structure.

Reported-by: Bamvor Jian Zhang 
Tested-by: Bamvor Jian Zhang 
Signed-off-by: Catalin Marinas 
Signed-off-by: Greg Kroah-Hartman

hx4700: regulator: declare full constraints

2015-03-06T22:40:52+00:00

commit a52d209336f8fc7483a8c7f4a8a7d2a8e1692a6c upstream.

Since the removal of CONFIG_REGULATOR_DUMMY option, the touchscreen stopped
working. This patch enables the "replacement" for REGULATOR_DUMMY and
allows the touchscreen to work even though there is no regulator for "vcc".

Signed-off-by: Martin Vajnar 
Signed-off-by: Robert Jarzmik 
Signed-off-by: Greg Kroah-Hartman

KVM: x86: update masterclock values on TSC writes

2015-03-06T22:40:52+00:00

commit 7f187922ddf6b67f2999a76dcb71663097b75497 upstream.

When the guest writes to the TSC, the masterclock TSC copy must be
updated as well along with the TSC_OFFSET update, otherwise a negative
tsc_timestamp is calculated at kvm_guest_time_update.

Once "if (!vcpus_matched && ka->use_master_clock)" is simplified to
"if (ka->use_master_clock)", the corresponding "if (!ka->use_master_clock)"
becomes redundant, so remove the do_request boolean and collapse
everything into a single condition.

Signed-off-by: Marcelo Tosatti 
Signed-off-by: Paolo Bonzini 
Signed-off-by: Greg Kroah-Hartman

KVM: MIPS: Don't leak FPU/DSP to guest

2015-03-06T22:40:52+00:00

commit f798217dfd038af981a18bbe4bc57027a08bb182 upstream.

The FPU and DSP are enabled via the CP0 Status CU1 and MX bits by
kvm_mips_set_c0_status() on a guest exit, presumably in case there is
active state that needs saving if pre-emption occurs. However neither of
these bits are cleared again when returning to the guest.

This effectively gives the guest access to the FPU/DSP hardware after
the first guest exit even though it is not aware of its presence,
allowing FP instructions in guest user code to intermittently actually
execute instead of trapping into the guest OS for emulation. It will
then read & manipulate the hardware FP registers which technically
belong to the user process (e.g. QEMU), or are stale from another user
process. It can also crash the guest OS by causing an FP exception, for
which a guest exception handler won't have been registered.

First lets save and disable the FPU (and MSA) state with lose_fpu(1)
before entering the guest. This simplifies the problem, especially for
when guest FPU/MSA support is added in the future, and prevents FR=1 FPU
state being live when the FR bit gets cleared for the guest, which
according to the architecture causes the contents of the FPU and vector
registers to become UNPREDICTABLE.

We can then safely remove the enabling of the FPU in
kvm_mips_set_c0_status(), since there should never be any active FPU or
MSA state to save at pre-emption, which should plug the FPU leak.

DSP state is always live rather than being lazily restored, so for that
it is simpler to just clear the MX bit again when re-entering the guest.

Signed-off-by: James Hogan 
Cc: Paolo Bonzini 
Cc: Ralf Baechle 
Cc: Sanjay Lal 
Cc: Gleb Natapov 
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc:  # v3.10+: 044f0f03eca0: MIPS: KVM: Deliver guest interrupts
Cc:  # v3.10+
Signed-off-by: Paolo Bonzini 
Signed-off-by: James Hogan 
Signed-off-by: Greg Kroah-Hartman

ARC: fix page address calculation if PAGE_OFFSET != LINUX_LINK_BASE

2015-03-06T22:40:52+00:00

commit 06f34e1c28f3608b0ce5b310e41102d3fe7b65a1 upstream.

We used to calculate page address differently in 2 cases:

1. In virt_to_page(x) we do
 --->8---
 mem_map + (x - CONFIG_LINUX_LINK_BASE) >> PAGE_SHIFT
 --->8---

2. In in pte_page(x) we do
 --->8---
 mem_map + (pte_val(x) - PAGE_OFFSET) >> PAGE_SHIFT
 --->8---

That leads to problems in case PAGE_OFFSET != CONFIG_LINUX_LINK_BASE -
different pages will be selected depending on where and how we calculate
page address.

In particular in the STAR 9000853582 when gdb attempted to read memory
of another process it got improper page in get_user_pages() because this
is exactly one of the places where we search for a page by pte_page().

The fix is trivial - we need to calculate page address similarly in both
cases.

Signed-off-by: Alexey Brodkin 
Signed-off-by: Vineet Gupta 
Signed-off-by: Greg Kroah-Hartman

ARM: pxa: add regulator_has_full_constraints to poodle board file

2015-03-06T22:40:52+00:00

commit 9bc78f32c2e430aebf6def965b316aa95e37a20c upstream.

Add regulator_has_full_constraints() call to poodle board file to let
regulator core know that we do not have any additional regulators left.
This lets it substitute unprovided regulators with dummy ones.

This fixes the following warnings that can be seen on poodle if
regulators are enabled:

ads7846 spi1.0: unable to get regulator: -517
spi spi1.0: Driver ads7846 requests probe deferral
wm8731 0-001b: Failed to get supply 'AVDD': -517
wm8731 0-001b: Failed to request supplies: -517
wm8731 0-001b: ASoC: failed to probe component -517

Signed-off-by: Dmitry Eremin-Solenikov 
Acked-by: Mark Brown 
Signed-off-by: Robert Jarzmik 
Signed-off-by: Greg Kroah-Hartman

ARM: pxa: add regulator_has_full_constraints to corgi board file

2015-03-06T22:40:51+00:00

commit 271e80176aae4e5b481f4bb92df9768c6075bbca upstream.

Add regulator_has_full_constraints() call to corgi board file to let
regulator core know that we do not have any additional regulators left.
This lets it substitute unprovided regulators with dummy ones.

This fixes the following warnings that can be seen on corgi if
regulators are enabled:

ads7846 spi1.0: unable to get regulator: -517
spi spi1.0: Driver ads7846 requests probe deferral
wm8731 0-001b: Failed to get supply 'AVDD': -517
wm8731 0-001b: Failed to request supplies: -517
wm8731 0-001b: ASoC: failed to probe component -517
corgi-audio corgi-audio: ASoC: failed to instantiate card -517

Signed-off-by: Dmitry Eremin-Solenikov 
Acked-by: Mark Brown 
Signed-off-by: Robert Jarzmik 
Signed-off-by: Greg Kroah-Hartman