linux.git, branch v4.9.77

Linux 4.9.77

2018-01-17T08:39:00+00:00

x86/pti/efi: broken conversion from efi to kernel page table

2018-01-17T08:39:00+00:00

The page table order must be increased for EFI table in order to avoid a
bug where NMI tries to change the page table to kernel page table, while
efi page table is active.

For more disccussion about this bug, see this thread:
http://lkml.iu.edu/hypermail/linux/kernel/1801.1/00951.html

Signed-off-by: Pavel Tatashin 
Reviewed-by: Steven Sistare 
Acked-by: Jiri Kosina 
Signed-off-by: Greg Kroah-Hartman

objtool: Fix retpoline support for pre-ORC objtool

2018-01-17T08:39:00+00:00

Objtool 1.0 (pre-ORC) produces the following warning when it encounters
a retpoline:

  arch/x86/crypto/camellia-aesni-avx2-asm_64.o: warning: objtool: .altinstr_replacement+0xf: return instruction outside of a callable function

That warning is meant to catch GCC bugs and missing ENTRY/ENDPROC
annotations, neither of which are applicable to alternatives.  Silence
the warning for alternative instructions, just like objtool 2.0 already
does.

Reported-by: David Woodhouse 
Signed-off-by: Josh Poimboeuf 
Signed-off-by: Greg Kroah-Hartman

x86/retpoline: Remove compile time warning

2018-01-17T08:39:00+00:00

commit b8b9ce4b5aec8de9e23cabb0a26b78641f9ab1d6 upstream.

Remove the compile time warning when CONFIG_RETPOLINE=y and the compiler
does not have retpoline support. Linus rationale for this is:

  It's wrong because it will just make people turn off RETPOLINE, and the
  asm updates - and return stack clearing - that are independent of the
  compiler are likely the most important parts because they are likely the
  ones easiest to target.

  And it's annoying because most people won't be able to do anything about
  it. The number of people building their own compiler? Very small. So if
  their distro hasn't got a compiler yet (and pretty much nobody does), the
  warning is just annoying crap.

  It is already properly reported as part of the sysfs interface. The
  compile-time warning only encourages bad things.

Fixes: 76b043848fd2 ("x86/retpoline: Add initial retpoline support")
Requested-by: Linus Torvalds 
Signed-off-by: Thomas Gleixner 
Cc: David Woodhouse 
Cc: Peter Zijlstra (Intel) 
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel 
Cc: Andi Kleen 
Cc: Josh Poimboeuf 
Cc: thomas.lendacky@amd.com
Cc: Linus Torvalds 
Cc: Jiri Kosina 
Cc: Andy Lutomirski 
Cc: Dave Hansen 
Cc: Kees Cook 
Cc: Tim Chen 
Cc: Greg Kroah-Hartman 
Link: https://lkml.kernel.org/r/CA+55aFzWgquv4i6Mab6bASqYXg3ErV3XDFEYf=GEcCDQg5uAtw@mail.gmail.com
Signed-off-by: Greg Kroah-Hartman

selftests/x86: Add test_vsyscall

2018-01-17T08:39:00+00:00

commit 352909b49ba0d74929b96af6dfbefc854ab6ebb5 upstream.

This tests that the vsyscall entries do what they're expected to do.
It also confirms that attempts to read the vsyscall page behave as
expected.

If changes are made to the vsyscall code or its memory map handling,
running this test in all three of vsyscall=none, vsyscall=emulate,
and vsyscall=native are helpful.

(Because it's easy, this also compares the vsyscall results to their
 vDSO equivalents.)

Note to KAISER backporters: please test this under all three
vsyscall modes.  Also, in the emulate and native modes, make sure
that test_vsyscall_64 agrees with the command line or config
option as to which mode you're in.  It's quite easy to mess up
the kernel such that native mode accidentally emulates
or vice versa.

Greg, etc: please backport this to all your Meltdown-patched
kernels.  It'll help make sure the patches didn't regress
vsyscalls.

CSigned-off-by: Andy Lutomirski 
Cc: Andy Lutomirski 
Cc: Borislav Petkov 
Cc: Dave Hansen 
Cc: Greg Kroah-Hartman 
Cc: H. Peter Anvin 
Cc: Hugh Dickins 
Cc: Josh Poimboeuf 
Cc: Juergen Gross 
Cc: Kees Cook 
Cc: Linus Torvalds 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/2b9c5a174c1d60fd7774461d518aa75598b1d8fd.1515719552.git.luto@kernel.org
Signed-off-by: Ingo Molnar 
Signed-off-by: Greg Kroah-Hartman

x86/retpoline: Fill return stack buffer on vmexit

2018-01-17T08:39:00+00:00

commit 117cc7a908c83697b0b737d15ae1eb5943afe35b upstream.

In accordance with the Intel and AMD documentation, we need to overwrite
all entries in the RSB on exiting a guest, to prevent malicious branch
target predictions from affecting the host kernel. This is needed both
for retpoline and for IBRS.

[ak: numbers again for the RSB stuffing labels]

Signed-off-by: David Woodhouse 
Signed-off-by: Thomas Gleixner 
Tested-by: Peter Zijlstra (Intel) 
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel 
Cc: Andi Kleen 
Cc: Josh Poimboeuf 
Cc: thomas.lendacky@amd.com
Cc: Linus Torvalds 
Cc: Jiri Kosina 
Cc: Andy Lutomirski 
Cc: Dave Hansen 
Cc: Kees Cook 
Cc: Tim Chen 
Cc: Greg Kroah-Hartman 
Cc: Paul Turner 
Link: https://lkml.kernel.org/r/1515755487-8524-1-git-send-email-dwmw@amazon.co.uk
Signed-off-by: David Woodhouse 
Signed-off-by: Greg Kroah-Hartman

x86/retpoline/irq32: Convert assembler indirect jumps

2018-01-17T08:38:59+00:00

commit 7614e913db1f40fff819b36216484dc3808995d4 upstream.

Convert all indirect jumps in 32bit irq inline asm code to use non
speculative sequences.

Signed-off-by: Andi Kleen 
Signed-off-by: Thomas Gleixner 
Acked-by: Arjan van de Ven 
Acked-by: Ingo Molnar 
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel 
Cc: Josh Poimboeuf 
Cc: thomas.lendacky@amd.com
Cc: Peter Zijlstra 
Cc: Linus Torvalds 
Cc: Jiri Kosina 
Cc: Andy Lutomirski 
Cc: Dave Hansen 
Cc: Kees Cook 
Cc: Tim Chen 
Cc: Greg Kroah-Hartman 
Cc: Paul Turner 
Link: https://lkml.kernel.org/r/1515707194-20531-12-git-send-email-dwmw@amazon.co.uk
Signed-off-by: David Woodhouse 
Signed-off-by: Greg Kroah-Hartman

x86/retpoline/checksum32: Convert assembler indirect jumps

2018-01-17T08:38:59+00:00

commit 5096732f6f695001fa2d6f1335a2680b37912c69 upstream.

Convert all indirect jumps in 32bit checksum assembler code to use
non-speculative sequences when CONFIG_RETPOLINE is enabled.

Signed-off-by: David Woodhouse 
Signed-off-by: Thomas Gleixner 
Acked-by: Arjan van de Ven 
Acked-by: Ingo Molnar 
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel 
Cc: Andi Kleen 
Cc: Josh Poimboeuf 
Cc: thomas.lendacky@amd.com
Cc: Peter Zijlstra 
Cc: Linus Torvalds 
Cc: Jiri Kosina 
Cc: Andy Lutomirski 
Cc: Dave Hansen 
Cc: Kees Cook 
Cc: Tim Chen 
Cc: Greg Kroah-Hartman 
Cc: Paul Turner 
Link: https://lkml.kernel.org/r/1515707194-20531-11-git-send-email-dwmw@amazon.co.uk
Signed-off-by: Greg Kroah-Hartman

x86/retpoline/xen: Convert Xen hypercall indirect jumps

2018-01-17T08:38:59+00:00

commit ea08816d5b185ab3d09e95e393f265af54560350 upstream.

Convert indirect call in Xen hypercall to use non-speculative sequence,
when CONFIG_RETPOLINE is enabled.

Signed-off-by: David Woodhouse 
Signed-off-by: Thomas Gleixner 
Acked-by: Arjan van de Ven 
Acked-by: Ingo Molnar 
Reviewed-by: Juergen Gross 
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel 
Cc: Andi Kleen 
Cc: Josh Poimboeuf 
Cc: thomas.lendacky@amd.com
Cc: Peter Zijlstra 
Cc: Linus Torvalds 
Cc: Jiri Kosina 
Cc: Andy Lutomirski 
Cc: Dave Hansen 
Cc: Kees Cook 
Cc: Tim Chen 
Cc: Greg Kroah-Hartman 
Cc: Paul Turner 
Link: https://lkml.kernel.org/r/1515707194-20531-10-git-send-email-dwmw@amazon.co.uk
Signed-off-by: David Woodhouse 
Signed-off-by: Greg Kroah-Hartman

x86/retpoline/hyperv: Convert assembler indirect jumps

2018-01-17T08:38:59+00:00

commit e70e5892b28c18f517f29ab6e83bd57705104b31 upstream.

Convert all indirect jumps in hyperv inline asm code to use non-speculative
sequences when CONFIG_RETPOLINE is enabled.

Signed-off-by: David Woodhouse 
Signed-off-by: Thomas Gleixner 
Acked-by: Arjan van de Ven 
Acked-by: Ingo Molnar 
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel 
Cc: Andi Kleen 
Cc: Josh Poimboeuf 
Cc: thomas.lendacky@amd.com
Cc: Peter Zijlstra 
Cc: Linus Torvalds 
Cc: Jiri Kosina 
Cc: Andy Lutomirski 
Cc: Dave Hansen 
Cc: Kees Cook 
Cc: Tim Chen 
Cc: Greg Kroah-Hartman 
Cc: Paul Turner 
Link: https://lkml.kernel.org/r/1515707194-20531-9-git-send-email-dwmw@amazon.co.uk
[ backport to 4.9, hopefully correct, not tested... - gregkh ]
Signed-off-by: Greg Kroah-Hartman