commit cff9ab2b291e64259d97add48fe073c081afe4e2 upstream. The array has a size of MAX_LOCAL_APIC, which can be as large as 32k, so it can consume up to 128k. The array has been there forever and was never used for anything useful other than a version mismatch check which was introduced in 2009. There is no reason to store the version in an array. The kernel is not prepared to handle different APIC versions anyway, so the real important part is to detect a version mismatch and warn about it, which can be done with a single variable as well. [ tglx: Massaged changelog ] Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> CC: Andy Lutomirski <luto@amacapital.net> CC: Borislav Petkov <bp@alien8.de> CC: Brian Gerst <brgerst@gmail.com> CC: Mike Travis <travis@sgi.com> Link: http://lkml.kernel.org/r/20160913181232.30815-1-dvlasenk@redhat.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f5fbf848303c8704d0e1a1e7cabd08fd0a49552f upstream. Merrifield2 is actually Moorefield. Rename it accordingly and drop tail digit from Merrifield1. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.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/20160906184254.94440-1-andriy.shevchenko@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d4b05923f579c234137317cdf9a5eb69ddab76d1 upstream.
Our XSAVE features are divided into two categories: those that
generate FPU exceptions, and those that do not. MPX and pkeys do
not generate FPU exceptions and thus can not be used lazily. We
disable them when lazy mode is forced on.
We have a pair of masks to collect these two sets of features, but
XFEATURE_MASK_PKRU was added to the wrong mask: XFEATURE_MASK_LAZY.
Fix it by moving the feature to XFEATURE_MASK_EAGER.
Note: this only causes problem if you boot with lazy FPU mode
(eagerfpu=off) which is *not* the default. It also only affects
hardware which is not currently publicly available. It looks like
eager mode is going away, but we still need this patch applied
to any kernel that has protection keys and lazy mode, which is 4.6
through 4.8 at this point, and 4.9 if the lazy removal isn't sent
to Linus for 4.9.
Fixes: c8df40098451 ("x86/fpu, x86/mm/pkeys: Add PKRU xsave fields and data structures")
Signed-off-by: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Hansen <dave@sr71.net>
Link: http://lkml.kernel.org/r/20161007162342.28A49813@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cr4_init_shadow() will panic on 486-like machines without CR4. Fix
it using __read_cr4_safe().
Reported-by: david@saggiorato.net
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Fixes: 1e02ce4cccdc ("x86: Store a per-cpu shadow copy of CR4")
Link: http://lkml.kernel.org/r/43a20f81fb504013bf613913dc25574b45336a61.1475091074.git.luto@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
get_user_ex(x, ptr) should zero x on failure. It's not a lot of a leak (at most we are leaking uninitialized 64bit value off the kernel stack, and in a fairly constrained situation, at that), but the fix is trivial, so... Cc: stable@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> [ This sat in different branch from the uaccess fixes since mid-August ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As already done with __copy_*_user(), mark copy_*_user() as __always_inline. Without this, the checks for things like __builtin_const_p() won't work consistently in either hardened usercopy nor the recent adjustments for detecting usercopy overflows at compile time. The change in kernel text size is detectable, but very small: text data bss dec hex filename 12118735 5768608 14229504 32116847 1ea106f vmlinux.before 12120207 5768608 14229504 32118319 1ea162f vmlinux.after Signed-off-by: Kees Cook <keescook@chromium.org>
There are three usercopy warnings which are currently being silenced for
gcc 4.6 and newer:
1) "copy_from_user() buffer size is too small" compile warning/error
This is a static warning which happens when object size and copy size
are both const, and copy size > object size. I didn't see any false
positives for this one. So the function warning attribute seems to
be working fine here.
Note this scenario is always a bug and so I think it should be
changed to *always* be an error, regardless of
CONFIG_DEBUG_STRICT_USER_COPY_CHECKS.
2) "copy_from_user() buffer size is not provably correct" compile warning
This is another static warning which happens when I enable
__compiletime_object_size() for new compilers (and
CONFIG_DEBUG_STRICT_USER_COPY_CHECKS). It happens when object size
is const, but copy size is *not*. In this case there's no way to
compare the two at build time, so it gives the warning. (Note the
warning is a byproduct of the fact that gcc has no way of knowing
whether the overflow function will be called, so the call isn't dead
code and the warning attribute is activated.)
So this warning seems to only indicate "this is an unusual pattern,
maybe you should check it out" rather than "this is a bug".
I get 102(!) of these warnings with allyesconfig and the
__compiletime_object_size() gcc check removed. I don't know if there
are any real bugs hiding in there, but from looking at a small
sample, I didn't see any. According to Kees, it does sometimes find
real bugs. But the false positive rate seems high.
3) "Buffer overflow detected" runtime warning
This is a runtime warning where object size is const, and copy size >
object size.
All three warnings (both static and runtime) were completely disabled
for gcc 4.6 with the following commit:
2fb0815c9ee6 ("gcc4: disable __compiletime_object_size for GCC 4.6+")
That commit mistakenly assumed that the false positives were caused by a
gcc bug in __compiletime_object_size(). But in fact,
__compiletime_object_size() seems to be working fine. The false
positives were instead triggered by #2 above. (Though I don't have an
explanation for why the warnings supposedly only started showing up in
gcc 4.6.)
So remove warning #2 to get rid of all the false positives, and re-enable
warnings #1 and #3 by reverting the above commit.
Furthermore, since #1 is a real bug which is detected at compile time,
upgrade it to always be an error.
Having done all that, CONFIG_DEBUG_STRICT_USER_COPY_CHECKS is no longer
needed.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: Nilay Vaish <nilayvaish@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull power management fixes from Rafael Wysocki:
"Two hibernation fixes allowing it to work with the recently added
randomization of the kernel identity mapping base on x86-64 and one
cpufreq driver regression fix.
Specifics:
- Fix the x86 identity mapping creation helpers to avoid the
assumption that the base address of the mapping will always be
aligned at the PGD level, as it may be aligned at the PUD level if
address space randomization is enabled (Rafael Wysocki).
- Fix the hibernation core to avoid executing tracing functions
before restoring the processor state completely during resume
(Thomas Garnier).
- Fix a recently introduced regression in the powernv cpufreq driver
that causes it to crash due to an out-of-bounds array access
(Akshay Adiga)"
* tag 'pm-4.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM / hibernate: Restore processor state before using per-CPU variables
x86/power/64: Always create temporary identity mapping correctly
cpufreq: powernv: Fix crash in gpstate_timer_handler()
Pull x86 fixes from Ingo Molnar: "This is bigger than usual - the reason is partly a pent-up stream of fixes after the merge window and partly accidental. The fixes are: - five patches to fix a boot failure on Andy Lutomirsky's laptop - four SGI UV platform fixes - KASAN fix - warning fix - documentation update - swap entry definition fix - pkeys fix - irq stats fix" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/apic/x2apic, smp/hotplug: Don't use before alloc in x2apic_cluster_probe() x86/efi: Allocate a trampoline if needed in efi_free_boot_services() x86/boot: Rework reserve_real_mode() to allow multiple tries x86/boot: Defer setup_real_mode() to early_initcall time x86/boot: Synchronize trampoline_cr4_features and mmu_cr4_features directly x86/boot: Run reserve_bios_regions() after we initialize the memory map x86/irq: Do not substract irq_tlb_count from irq_call_count x86/mm: Fix swap entry comment and macro x86/mm/kaslr: Fix -Wformat-security warning x86/mm/pkeys: Fix compact mode by removing protection keys' XSAVE buffer manipulation x86/build: Reduce the W=1 warnings noise when compiling x86 syscall tables x86/platform/UV: Fix kernel panic running RHEL kdump kernel on UV systems x86/platform/UV: Fix problem with UV4 BIOS providing incorrect PXM values x86/platform/UV: Fix bug with iounmap() of the UV4 EFI System Table causing a crash x86/platform/UV: Fix problem with UV4 Socket IDs not being contiguous x86/entry: Clarify the RF saving/restoring situation with SYSCALL/SYSRET x86/mm: Disable preemption during CR3 read+write x86/mm/KASLR: Increase BRK pages for KASLR memory randomization x86/mm/KASLR: Fix physical memory calculation on KASLR memory randomization x86, kasan, ftrace: Put APIC interrupt handlers into .irqentry.text
* pm-sleep: PM / hibernate: Restore processor state before using per-CPU variables x86/power/64: Always create temporary identity mapping correctly * pm-cpufreq: cpufreq: powernv: Fix crash in gpstate_timer_handler()