From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:53632 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752017AbdL0Pa2 (ORCPT ); Wed, 27 Dec 2017 10:30:28 -0500 Subject: Patch "x86/cpu_entry_area: Prevent wraparound in setup_cpu_entry_area_ptes() on 32bit" has been added to the 4.14-stable tree To: tglx@linutronix.de, bp@alien8.de, fengguang.wu@intel.com, gregkh@linuxfoundation.org Cc: , From: Date: Wed, 27 Dec 2017 16:26:11 +0100 Message-ID: <1514388371246195@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled x86/cpu_entry_area: Prevent wraparound in setup_cpu_entry_area_ptes() on 32bit 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-cpu_entry_area-prevent-wraparound-in-setup_cpu_entry_area_ptes-on-32bit.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 know about it. >>From f6c4fd506cb626e4346aa81688f255e593a7c5a0 Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Sat, 23 Dec 2017 19:45:11 +0100 Subject: x86/cpu_entry_area: Prevent wraparound in setup_cpu_entry_area_ptes() on 32bit From: Thomas Gleixner commit f6c4fd506cb626e4346aa81688f255e593a7c5a0 upstream. The loop which populates the CPU entry area PMDs can wrap around on 32bit machines when the number of CPUs is small. It worked wonderful for NR_CPUS=64 for whatever reason and the moron who wrote that code did not bother to test it with !SMP. Check for the wraparound to fix it. Fixes: 92a0f81d8957 ("x86/cpu_entry_area: Move it out of the fixmap") Reported-by: kernel test robot Signed-off-by: Thomas "Feels stupid" Gleixner Tested-by: Borislav Petkov Signed-off-by: Greg Kroah-Hartman --- arch/x86/mm/cpu_entry_area.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/arch/x86/mm/cpu_entry_area.c +++ b/arch/x86/mm/cpu_entry_area.c @@ -122,7 +122,8 @@ static __init void setup_cpu_entry_area_ start = CPU_ENTRY_AREA_BASE; end = start + CPU_ENTRY_AREA_MAP_SIZE; - for (; start < end; start += PMD_SIZE) + /* Careful here: start + PMD_SIZE might wrap around */ + for (; start < end && start >= CPU_ENTRY_AREA_BASE; start += PMD_SIZE) populate_extra_pte(start); #endif } Patches currently in stable-queue which might be from tglx@linutronix.de 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-decoder-fix-and-update-the-opcodes-map.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-cpu_entry_area-prevent-wraparound-in-setup_cpu_entry_area_ptes-on-32bit.patch queue-4.14/x86-mm-remove-superfluous-barriers.patch queue-4.14/x86-ldt-rework-locking.patch queue-4.14/pci-pm-force-devices-to-d0-in-pci_pm_thaw_noirq.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/tools-headers-sync-objtool-uapi-header.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/objtool-fix-64-bit-build-on-32-bit-host.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/objtool-move-synced-files-to-their-original-relative-locations.patch queue-4.14/x86-mm-use-__flush_tlb_one-for-kernel-memory.patch queue-4.14/objtool-move-kernel-headers-code-sync-check-to-a-script.patch queue-4.14/x86-mm-64-improve-the-memory-map-documentation.patch queue-4.14/objtool-fix-cross-build.patch