linux/arch/x86
Dave Hansen 8e8efe0379 x86/mpx: Fix instruction decoder condition
MPX decodes instructions in order to tell which bounds register
was violated.  Part of this decoding involves looking at the "REX
prefix" which is a special instrucion prefix used to retrofit
support for new registers in to old instructions.

The X86_REX_*() macros are defined to return actual bit values:

	#define X86_REX_R(rex) ((rex) & 4)

*not* boolean values.  However, the MPX code was checking for
them like they were booleans.  This might have led to us
mis-decoding the "REX prefix" and giving false information out to
userspace about bounds violations.  X86_REX_B() actually is bit 1,
so this is really only broken for the X86_REX_X() case.

Fix the conditionals up to tolerate the non-boolean values.

Fixes: fcc7ffd679 "x86, mpx: Decode MPX instruction to get bound violation information"
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: x86@kernel.org
Cc: Dave Hansen <dave@sr71.net>
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20151201003113.D800C1E0@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-12-05 18:52:14 +01:00
..
boot x86/mm: Fix regression with huge pages on PAE 2015-12-04 09:14:27 +01:00
configs Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2015-09-04 15:49:32 -07:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2015-11-04 09:11:12 -08:00
entry x86/entry/64: Fix irqflag tracing wrt context tracking 2015-11-24 09:55:02 +01:00
ia32 Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-11-03 21:05:40 -08:00
include x86/mm: Fix regression with huge pages on PAE 2015-12-04 09:14:27 +01:00
kernel x86 smpboot: Re-enable init_udelay=0 by default on modern CPUs 2015-11-25 23:17:48 +01:00
kvm Four changes: 2015-11-12 14:34:06 -08:00
lguest genirq: Remove irq argument from irq flow handlers 2015-09-16 15:47:51 +02:00
lib Linux 4.3-rc1 2015-09-13 11:25:35 +02:00
math-emu Merge branch 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-11-03 21:05:40 -08:00
mm x86/mpx: Fix instruction decoder condition 2015-12-05 18:52:14 +01:00
net ebpf: migrate bpf_prog's flags to bitfield 2015-10-03 05:02:39 -07:00
oprofile
pci PCI changes for the v4.4 merge window: 2015-11-06 11:29:53 -08:00
platform Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-11-03 21:33:18 -08:00
power x86/ldt: Make modify_ldt synchronous 2015-07-31 10:23:23 +02:00
purgatory
ras x86/ras/mce_amd_inj: Inject bank 4 errors on the NBC 2015-10-12 16:15:48 +02:00
realmode
tools
um Merge branch 'for-linus-4.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml 2015-11-10 16:33:37 -08:00
video
xen xen: features for 4.4-rc0 2015-11-04 17:32:42 -08:00
.gitignore
Kbuild x86/asm/entry, x86/vdso: Move the vDSO code to arch/x86/entry/vdso/ 2015-06-03 18:51:37 +02:00
Kconfig Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2015-11-03 18:59:10 -08:00
Kconfig.cpu x86/Kconfig/cpus: Fix/complete CPU type help texts 2015-10-21 11:12:56 +02:00
Kconfig.debug x86: don't make DEBUG_WX default to 'y' even with DEBUG_RODATA 2015-11-06 09:12:41 -08:00
Makefile Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2015-11-04 09:11:12 -08:00
Makefile_32.cpu
Makefile.um