linux/arch/x86
Eric Biggers e63e5d5c15 x86/fpu: Introduce validate_xstate_header()
Move validation of user-supplied xstate_header into a helper function,
in preparation of calling it from both the ptrace and sigreturn syscall
paths.

The new function also considers it to be an error if *any* reserved bits
are set, whereas before we were just clearing most of them silently.

This should reduce the chance of bugs that fail to correctly validate
user-supplied XSAVE areas.  It also will expose any broken userspace
programs that set the other reserved bits; this is desirable because
such programs will lose compatibility with future CPUs and kernels if
those bits are ever used for anything.  (There shouldn't be any such
programs, and in fact in the case where the compacted format is in use
we were already validating xfeatures.  But you never know...)

Signed-off-by: Eric Biggers <ebiggers@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Kevin Hao <haokexin@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Michael Halcrow <mhalcrow@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Cc: kernel-hardening@lists.openwall.com
Link: http://lkml.kernel.org/r/20170924105913.9157-2-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-26 09:43:45 +02:00
..
boot Merge branch 'efi-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-09-07 09:42:35 -07:00
configs Merge branch 'x86/urgent' into x86/asm, to pick up fixes 2017-08-10 13:14:15 +02:00
crypto crypto: x86/twofish - Fix RBP usage 2017-09-20 17:42:38 +08:00
entry Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-09-04 17:43:56 -07:00
events Merge branch 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-09-04 13:56:37 -07:00
hyperv tracing/hyper-v: Trace hyperv_mmu_flush_tlb_others() 2017-08-31 14:20:37 +02:00
ia32 x86/fpu: Rename fpu::fpstate_active to fpu::initialized 2017-09-26 09:43:36 +02:00
include x86/fpu: Introduce validate_xstate_header() 2017-09-26 09:43:45 +02:00
kernel x86/fpu: Introduce validate_xstate_header() 2017-09-26 09:43:45 +02:00
kvm x86/fpu: Rename fpu__activate_curr() to fpu__initialize() 2017-09-26 09:43:44 +02:00
lib x86/boot: Add early cmdline parsing for options with arguments 2017-07-18 11:38:06 +02:00
math-emu x86/fpu: Rename fpu__activate_curr() to fpu__initialize() 2017-09-26 09:43:44 +02:00
mm x86/fpu: Rename fpu::fpstate_active to fpu::initialized 2017-09-26 09:43:36 +02:00
net x86: bpf_jit: small optimization in emit_bpf_tail_call() 2017-08-31 11:57:37 -07:00
oprofile
pci dmi: Mark all struct dmi_system_id instances const 2017-09-14 11:59:30 +02:00
platform Merge branch 'i2c/for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2017-09-09 14:18:40 -07:00
power dmi: Mark all struct dmi_system_id instances const 2017-09-14 11:59:30 +02:00
purgatory
ras x86/mce: Merge mce_amd_inj into mce-inject 2017-06-14 07:32:07 +02:00
realmode x86/boot/realmode: Check for memory encryption on the APs 2017-07-18 11:38:04 +02:00
tools
um um: remove a stray tab 2017-09-13 22:36:27 +02:00
video
xen xen: Fixes for rc2 2017-09-22 06:40:47 -10:00
.gitignore
Kbuild Merge branch 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-09-07 09:25:15 -07:00
Kconfig libnvdimm for 4.14 2017-09-11 13:10:57 -07:00
Kconfig.cpu
Kconfig.debug Merge branch 'x86/asm' into locking/core 2017-08-18 10:29:54 +02:00
Makefile x86/build: Use cc-option to validate stack alignment parameter 2017-08-21 09:53:15 +02:00
Makefile_32.cpu kbuild: remove cc-option-align 2017-06-25 12:43:00 +09:00
Makefile.um