Patch "x86/vsyscall/64: Warn and fail vsyscall emulation in NATIVE mode" has been added to the 4.14-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    x86/vsyscall/64: Warn and fail vsyscall emulation in NATIVE mode

to the 4.14-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     x86-vsyscall-64-warn-and-fail-vsyscall-emulation-in-native-mode.patch
and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 4831b779403a836158917d59a7ca880483c67378 Mon Sep 17 00:00:00 2001
From: Andy Lutomirski <luto@kernel.org>
Date: Sun, 10 Dec 2017 22:47:20 -0800
Subject: x86/vsyscall/64: Warn and fail vsyscall emulation in NATIVE mode

From: Andy Lutomirski <luto@kernel.org>

commit 4831b779403a836158917d59a7ca880483c67378 upstream.

If something goes wrong with pagetable setup, vsyscall=native will
accidentally fall back to emulation.  Make it warn and fail so that we
notice.

Signed-off-by: Andy Lutomirski <luto@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Laight <David.Laight@aculab.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/x86/entry/vsyscall/vsyscall_64.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/arch/x86/entry/vsyscall/vsyscall_64.c
+++ b/arch/x86/entry/vsyscall/vsyscall_64.c
@@ -139,6 +139,10 @@ bool emulate_vsyscall(struct pt_regs *re
 
 	WARN_ON_ONCE(address != regs->ip);
 
+	/* This should be unreachable in NATIVE mode. */
+	if (WARN_ON(vsyscall_mode == NATIVE))
+		return false;
+
 	if (vsyscall_mode == NONE) {
 		warn_bad_vsyscall(KERN_INFO, regs,
 				  "vsyscall attempted with vsyscall=none");


Patches currently in stable-queue which might be from luto@kernel.org are

queue-4.14/x86-entry-rename-sysenter_stack-to-cpu_entry_area_entry_stack.patch
queue-4.14/x86-mm-put-mmu-to-hardware-asid-translation-in-one-place.patch
queue-4.14/x86-vsyscall-64-explicitly-set-_page_user-in-the-pagetable-hierarchy.patch
queue-4.14/x86-uv-use-the-right-tlb-flush-api.patch
queue-4.14/x86-mm-dump_pagetables-check-page_present-for-real.patch
queue-4.14/x86-ldt-prevent-ldt-inheritance-on-exec.patch
queue-4.14/x86-microcode-dont-abuse-the-tlb-flush-interface.patch
queue-4.14/x86-doc-remove-obvious-weirdnesses-from-the-x86-mm-layout-documentation.patch
queue-4.14/init-invoke-init_espfix_bsp-from-mm_init.patch
queue-4.14/x86-cpu_entry_area-move-it-to-a-separate-unit.patch
queue-4.14/x86-vsyscall-64-warn-and-fail-vsyscall-emulation-in-native-mode.patch
queue-4.14/x86-mm-create-asm-invpcid.h.patch
queue-4.14/x86-mm-remove-superfluous-barriers.patch
queue-4.14/x86-ldt-rework-locking.patch
queue-4.14/arch-mm-allow-arch_dup_mmap-to-fail.patch
queue-4.14/x86-cpu_entry_area-move-it-out-of-the-fixmap.patch
queue-4.14/x86-mm-remove-hard-coded-asid-limit-checks.patch
queue-4.14/x86-kconfig-limit-nr_cpus-on-32-bit-to-a-sane-amount.patch
queue-4.14/x86-mm-add-comments-to-clarify-which-tlb-flush-functions-are-supposed-to-flush-what.patch
queue-4.14/x86-mm-move-the-cr3-construction-functions-to-tlbflush.h.patch
queue-4.14/x86-mm-dump_pagetables-make-the-address-hints-correct-and-readable.patch
queue-4.14/x86-insn-eval-add-utility-functions-to-get-segment-selector.patch
queue-4.14/x86-mm-use-__flush_tlb_one-for-kernel-memory.patch
queue-4.14/x86-mm-64-improve-the-memory-map-documentation.patch