linux-stable.git/Documentation, branch v4.15.2 Linux kernel stable tree x86/paravirt: Remove 'noreplace-paravirt' cmdline option 2018-02-07T19:14:13+00:00 Josh Poimboeuf jpoimboe@redhat.com 2018-01-31T04:13:33+00:00 6e337065e6de2a79f2e508ec8e04fdc845edaeb7 commit 12c69f1e94c89d40696e83804dd2f0965b5250cd The 'noreplace-paravirt' option disables paravirt patching, leaving the original pv indirect calls in place. That's highly incompatible with retpolines, unless we want to uglify paravirt even further and convert the paravirt calls to retpolines. As far as I can tell, the option doesn't seem to be useful for much other than introducing surprising corner cases and making the kernel vulnerable to Spectre v2. It was probably a debug option from the early paravirt days. So just remove it. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Juergen Gross <jgross@suse.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Greg KH <gregkh@linuxfoundation.org> Cc: Jun Nakajima <jun.nakajima@intel.com> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Asit Mallick <asit.k.mallick@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Jason Baron <jbaron@akamai.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Alok Kataria <akataria@vmware.com> Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com> Cc: David Woodhouse <dwmw2@infradead.org> Cc: Dan Williams <dan.j.williams@intel.com> Link: https://lkml.kernel.org/r/20180131041333.2x6blhxirc2kclrq@treble Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 12c69f1e94c89d40696e83804dd2f0965b5250cd

The 'noreplace-paravirt' option disables paravirt patching, leaving the
original pv indirect calls in place.

That's highly incompatible with retpolines, unless we want to uglify
paravirt even further and convert the paravirt calls to retpolines.

As far as I can tell, the option doesn't seem to be useful for much
other than introducing surprising corner cases and making the kernel
vulnerable to Spectre v2.  It was probably a debug option from the early
paravirt days.  So just remove it.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Jun Nakajima <jun.nakajima@intel.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Alok Kataria <akataria@vmware.com>
Cc: Arjan Van De Ven <arjan.van.de.ven@intel.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Link: https://lkml.kernel.org/r/20180131041333.2x6blhxirc2kclrq@treble
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Documentation: Document array_index_nospec 2018-02-07T19:14:10+00:00 Mark Rutland mark.rutland@arm.com 2018-01-30T01:02:16+00:00 a35f71001b4048eb68bbcbbb01940e06a4e55881 commit f84a56f73dddaeac1dba8045b007f742f61cd2da Document the rationale and usage of the new array_index_nospec() helper. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Kees Cook <keescook@chromium.org> Cc: linux-arch@vger.kernel.org Cc: Jonathan Corbet <corbet@lwn.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: gregkh@linuxfoundation.org Cc: kernel-hardening@lists.openwall.com Cc: torvalds@linux-foundation.org Cc: alan@linux.intel.com Link: https://lkml.kernel.org/r/151727413645.33451.15878817161436755393.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit f84a56f73dddaeac1dba8045b007f742f61cd2da

Document the rationale and usage of the new array_index_nospec() helper.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: linux-arch@vger.kernel.org
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: gregkh@linuxfoundation.org
Cc: kernel-hardening@lists.openwall.com
Cc: torvalds@linux-foundation.org
Cc: alan@linux.intel.com
Link: https://lkml.kernel.org/r/151727413645.33451.15878817161436755393.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-01-21T18:48:35+00:00 Linus Torvalds torvalds@linux-foundation.org 2018-01-21T18:48:35+00:00 5515114211c5096987b8e622c2ca57929cebabaa Pull x86 pti fixes from Thomas Gleixner: "A small set of fixes for the meltdown/spectre mitigations: - Make kprobes aware of retpolines to prevent probes in the retpoline thunks. - Make the machine check exception speculation protected. MCE used to issue an indirect call directly from the ASM entry code. Convert that to a direct call into a C-function and issue the indirect call from there so the compiler can add the retpoline protection, - Make the vmexit_fill_RSB() assembly less stupid - Fix a typo in the PTI documentation" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/retpoline: Optimize inline assembler for vmexit_fill_RSB x86/pti: Document fix wrong index kprobes/x86: Disable optimizing on the function jumps to indirect thunk kprobes/x86: Blacklist indirect thunk functions for kprobes retpoline: Introduce start/end markers of indirect thunk x86/mce: Make machine check speculation protected 
Pull x86 pti fixes from Thomas Gleixner:
 "A small set of fixes for the meltdown/spectre mitigations:

   - Make kprobes aware of retpolines to prevent probes in the retpoline
     thunks.

   - Make the machine check exception speculation protected. MCE used to
     issue an indirect call directly from the ASM entry code. Convert
     that to a direct call into a C-function and issue the indirect call
     from there so the compiler can add the retpoline protection,

   - Make the vmexit_fill_RSB() assembly less stupid

   - Fix a typo in the PTI documentation"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/retpoline: Optimize inline assembler for vmexit_fill_RSB
  x86/pti: Document fix wrong index
  kprobes/x86: Disable optimizing on the function jumps to indirect thunk
  kprobes/x86: Blacklist indirect thunk functions for kprobes
  retpoline: Introduce start/end markers of indirect thunk
  x86/mce: Make machine check speculation protected
x86/pti: Document fix wrong index 2018-01-19T15:31:29+00:00 zhenwei.pi zhenwei.pi@youruncloud.com 2018-01-18T01:04:52+00:00 98f0fceec7f84d80bc053e49e596088573086421 In section <2. Runtime Cost>, fix wrong index. Signed-off-by: zhenwei.pi <zhenwei.pi@youruncloud.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: dave.hansen@linux.intel.com Link: https://lkml.kernel.org/r/1516237492-27739-1-git-send-email-zhenwei.pi@youruncloud.com 
In section <2. Runtime Cost>, fix wrong index.

Signed-off-by: zhenwei.pi <zhenwei.pi@youruncloud.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: dave.hansen@linux.intel.com
Link: https://lkml.kernel.org/r/1516237492-27739-1-git-send-email-zhenwei.pi@youruncloud.com
KVM: PPC: Book3S: Provide information about hardware/firmware CVE workarounds 2018-01-19T04:17:01+00:00 Paul Mackerras paulus@ozlabs.org 2018-01-15T05:06:47+00:00 3214d01f139b7544e870fc0b7fcce8da13c1cb51 This adds a new ioctl, KVM_PPC_GET_CPU_CHAR, that gives userspace information about the underlying machine's level of vulnerability to the recently announced vulnerabilities CVE-2017-5715, CVE-2017-5753 and CVE-2017-5754, and whether the machine provides instructions to assist software to work around the vulnerabilities. The ioctl returns two u64 words describing characteristics of the CPU and required software behaviour respectively, plus two mask words which indicate which bits have been filled in by the kernel, for extensibility. The bit definitions are the same as for the new H_GET_CPU_CHARACTERISTICS hypercall. There is also a new capability, KVM_CAP_PPC_GET_CPU_CHAR, which indicates whether the new ioctl is available. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> 
This adds a new ioctl, KVM_PPC_GET_CPU_CHAR, that gives userspace
information about the underlying machine's level of vulnerability
to the recently announced vulnerabilities CVE-2017-5715,
CVE-2017-5753 and CVE-2017-5754, and whether the machine provides
instructions to assist software to work around the vulnerabilities.

The ioctl returns two u64 words describing characteristics of the
CPU and required software behaviour respectively, plus two mask
words which indicate which bits have been filled in by the kernel,
for extensibility.  The bit definitions are the same as for the
new H_GET_CPU_CHARACTERISTICS hypercall.

There is also a new capability, KVM_CAP_PPC_GET_CPU_CHAR, which
indicates whether the new ioctl is available.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-01-14T17:51:25+00:00 Linus Torvalds torvalds@linux-foundation.org 2018-01-14T17:51:25+00:00 40548c6b6c134275c750eb372dc2cf8ee1bbc3d4 Pull x86 pti updates from Thomas Gleixner: "This contains: - a PTI bugfix to avoid setting reserved CR3 bits when PCID is disabled. This seems to cause issues on a virtual machine at least and is incorrect according to the AMD manual. - a PTI bugfix which disables the perf BTS facility if PTI is enabled. The BTS AUX buffer is not globally visible and causes the CPU to fault when the mapping disappears on switching CR3 to user space. A full fix which restores BTS on PTI is non trivial and will be worked on. - PTI bugfixes for EFI and trusted boot which make sure that the user space visible page table entries have the NX bit cleared - removal of dead code in the PTI pagetable setup functions - add PTI documentation - add a selftest for vsyscall to verify that the kernel actually implements what it advertises. - a sysfs interface to expose vulnerability and mitigation information so there is a coherent way for users to retrieve the status. - the initial spectre_v2 mitigations, aka retpoline: + The necessary ASM thunk and compiler support + The ASM variants of retpoline and the conversion of affected ASM code + Make LFENCE serializing on AMD so it can be used as speculation trap + The RSB fill after vmexit - initial objtool support for retpoline As I said in the status mail this is the most of the set of patches which should go into 4.15 except two straight forward patches still on hold: - the retpoline add on of LFENCE which waits for ACKs - the RSB fill after context switch Both should be ready to go early next week and with that we'll have covered the major holes of spectre_v2 and go back to normality" * 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (28 commits) x86,perf: Disable intel_bts when PTI security/Kconfig: Correct the Documentation reference for PTI x86/pti: Fix !PCID and sanitize defines selftests/x86: Add test_vsyscall x86/retpoline: Fill return stack buffer on vmexit x86/retpoline/irq32: Convert assembler indirect jumps x86/retpoline/checksum32: Convert assembler indirect jumps x86/retpoline/xen: Convert Xen hypercall indirect jumps x86/retpoline/hyperv: Convert assembler indirect jumps x86/retpoline/ftrace: Convert ftrace assembler indirect jumps x86/retpoline/entry: Convert entry assembler indirect jumps x86/retpoline/crypto: Convert crypto assembler indirect jumps x86/spectre: Add boot time option to select Spectre v2 mitigation x86/retpoline: Add initial retpoline support objtool: Allow alternatives to be ignored objtool: Detect jumps to retpoline thunks x86/pti: Make unpoison of pgd for trusted boot work for real x86/alternatives: Fix optimize_nops() checking sysfs/cpu: Fix typos in vulnerability documentation x86/cpu/AMD: Use LFENCE_RDTSC in preference to MFENCE_RDTSC ... 
Pull x86 pti updates from Thomas Gleixner:
 "This contains:

   - a PTI bugfix to avoid setting reserved CR3 bits when PCID is
     disabled. This seems to cause issues on a virtual machine at least
     and is incorrect according to the AMD manual.

   - a PTI bugfix which disables the perf BTS facility if PTI is
     enabled. The BTS AUX buffer is not globally visible and causes the
     CPU to fault when the mapping disappears on switching CR3 to user
     space. A full fix which restores BTS on PTI is non trivial and will
     be worked on.

   - PTI bugfixes for EFI and trusted boot which make sure that the user
     space visible page table entries have the NX bit cleared

   - removal of dead code in the PTI pagetable setup functions

   - add PTI documentation

   - add a selftest for vsyscall to verify that the kernel actually
     implements what it advertises.

   - a sysfs interface to expose vulnerability and mitigation
     information so there is a coherent way for users to retrieve the
     status.

   - the initial spectre_v2 mitigations, aka retpoline:

      + The necessary ASM thunk and compiler support

      + The ASM variants of retpoline and the conversion of affected ASM
        code

      + Make LFENCE serializing on AMD so it can be used as speculation
        trap

      + The RSB fill after vmexit

   - initial objtool support for retpoline

  As I said in the status mail this is the most of the set of patches
  which should go into 4.15 except two straight forward patches still on
  hold:

   - the retpoline add on of LFENCE which waits for ACKs

   - the RSB fill after context switch

  Both should be ready to go early next week and with that we'll have
  covered the major holes of spectre_v2 and go back to normality"

* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (28 commits)
  x86,perf: Disable intel_bts when PTI
  security/Kconfig: Correct the Documentation reference for PTI
  x86/pti: Fix !PCID and sanitize defines
  selftests/x86: Add test_vsyscall
  x86/retpoline: Fill return stack buffer on vmexit
  x86/retpoline/irq32: Convert assembler indirect jumps
  x86/retpoline/checksum32: Convert assembler indirect jumps
  x86/retpoline/xen: Convert Xen hypercall indirect jumps
  x86/retpoline/hyperv: Convert assembler indirect jumps
  x86/retpoline/ftrace: Convert ftrace assembler indirect jumps
  x86/retpoline/entry: Convert entry assembler indirect jumps
  x86/retpoline/crypto: Convert crypto assembler indirect jumps
  x86/spectre: Add boot time option to select Spectre v2 mitigation
  x86/retpoline: Add initial retpoline support
  objtool: Allow alternatives to be ignored
  objtool: Detect jumps to retpoline thunks
  x86/pti: Make unpoison of pgd for trusted boot work for real
  x86/alternatives: Fix optimize_nops() checking
  sysfs/cpu: Fix typos in vulnerability documentation
  x86/cpu/AMD: Use LFENCE_RDTSC in preference to MFENCE_RDTSC
  ...
Merge tag 'usb-4.15-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb 2018-01-13T22:10:32+00:00 Linus Torvalds torvalds@linux-foundation.org 2018-01-13T22:10:32+00:00 2c1cfa49901839136e578ca516a7e230182da024 Pull USB fixes from Greg KH: "Here are some small USB fixes and device ids for 4.15-rc8 Nothing major, small fixes for various devices, some resolutions for bugs found by fuzzers, and the usual handful of new device ids. All of these have been in linux-next with no reported issues" * tag 'usb-4.15-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: Documentation: usb: fix typo in UVC gadgetfs config command usb: misc: usb3503: make sure reset is low for at least 100us uas: ignore UAS for Norelsys NS1068(X) chips USB: UDC core: fix double-free in usb_add_gadget_udc_release USB: fix usbmon BUG trigger usbip: vudc_tx: fix v_send_ret_submit() vulnerability to null xfer buffer usbip: remove kernel addresses from usb device and urb debug msgs usbip: fix vudc_rx: harden CMD_SUBMIT path to handle malicious input USB: serial: cp210x: add new device ID ELV ALC 8xxx USB: serial: cp210x: add IDs for LifeScan OneTouch Verio IQ 
Pull USB fixes from Greg KH:
 "Here are some small USB fixes and device ids for 4.15-rc8

  Nothing major, small fixes for various devices, some resolutions for
  bugs found by fuzzers, and the usual handful of new device ids.

  All of these have been in linux-next with no reported issues"

* tag 'usb-4.15-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  Documentation: usb: fix typo in UVC gadgetfs config command
  usb: misc: usb3503: make sure reset is low for at least 100us
  uas: ignore UAS for Norelsys NS1068(X) chips
  USB: UDC core: fix double-free in usb_add_gadget_udc_release
  USB: fix usbmon BUG trigger
  usbip: vudc_tx: fix v_send_ret_submit() vulnerability to null xfer buffer
  usbip: remove kernel addresses from usb device and urb debug msgs
  usbip: fix vudc_rx: harden CMD_SUBMIT path to handle malicious input
  USB: serial: cp210x: add new device ID ELV ALC 8xxx
  USB: serial: cp210x: add IDs for LifeScan OneTouch Verio IQ
Merge tag 'kbuild-fixes-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild 2018-01-13T21:24:56+00:00 Linus Torvalds torvalds@linux-foundation.org 2018-01-13T21:24:56+00:00 22079ee4501d99492b34482a555f90e6bf39590f Pull Kbuild fixes from Masahiro Yamada: - fix cross-compilation for architectures that setup CROSS_COMPILE in their arch Makefile - fix Kconfig rational operators for bool / tristate - drop a gperf-generated file from .gitignore * tag 'kbuild-fixes-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: genksyms: drop *.hash.c from .gitignore kconfig: fix relational operators for bool and tristate symbols kbuild: move cc-option and cc-disable-warning after incl. arch Makefile 
Pull Kbuild fixes from Masahiro Yamada:

 - fix cross-compilation for architectures that setup CROSS_COMPILE in
   their arch Makefile

 - fix Kconfig rational operators for bool / tristate

 - drop a gperf-generated file from .gitignore

* tag 'kbuild-fixes-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  genksyms: drop *.hash.c from .gitignore
  kconfig: fix relational operators for bool and tristate symbols
  kbuild: move cc-option and cc-disable-warning after incl. arch Makefile
Merge tag 'pci-v4.15-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci 2018-01-13T21:14:54+00:00 Linus Torvalds torvalds@linux-foundation.org 2018-01-13T21:14:54+00:00 8e66791a80abd0e86ac1995395129791eefe50b5 Pull PCI fixes from Bjorn Helgaas: "Fix AMD boot regression due to 64-bit window conflicting with system memory (Christian König)" * tag 'pci-v4.15-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: x86/PCI: Move and shrink AMD 64-bit window to avoid conflict x86/PCI: Add "pci=big_root_window" option for AMD 64-bit windows 
Pull PCI fixes from Bjorn Helgaas:
 "Fix AMD boot regression due to 64-bit window conflicting with system
  memory (Christian König)"

* tag 'pci-v4.15-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  x86/PCI: Move and shrink AMD 64-bit window to avoid conflict
  x86/PCI: Add "pci=big_root_window" option for AMD 64-bit windows
Merge branch 'akpm' (patches from Andrew) 2018-01-13T19:07:55+00:00 Linus Torvalds torvalds@linux-foundation.org 2018-01-13T19:07:55+00:00 ed93de8420a342785da7585b06c107ae32f73b2b Merge misc fixlets from Andrew Morton: "4 fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: tools/objtool/Makefile: don't assume sync-check.sh is executable kdump: write correct address of mem_section into vmcoreinfo kmemleak: allow to coexist with fault injection MAINTAINERS, nilfs2: change project home URLs 
Merge misc fixlets from Andrew Morton:
 "4 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  tools/objtool/Makefile: don't assume sync-check.sh is executable
  kdump: write correct address of mem_section into vmcoreinfo
  kmemleak: allow to coexist with fault injection
  MAINTAINERS, nilfs2: change project home URLs