Dave Hansen a44ca8f5a3 x86/pti: Reduce amount of kernel text allowed to be Global ...

commit abb67605203687c8b7943d760638d0301787f8d9

Kees reported to me that I made too much of the kernel image global.
It was far more than just text:

	I think this is too much set global: _end is after data,
	bss, and brk, and all kinds of other stuff that could
	hold secrets. I think this should match what
	mark_rodata_ro() is doing.

This does exactly that.  We use __end_rodata_hpage_align as our
marker both because it is huge-page-aligned and it does not contain
any sections we expect to hold secrets.

Kees's logic was that r/o data is in the kernel image anyway and,
in the case of traditional distributions, can be freely downloaded
from the web, so there's no reason to hide it.

Fixes: 8c06c7740 (x86/pti: Leave kernel text global for !PCID)
Reported-by: Kees Cook <keescook@google.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ingo Molnar <mingo@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: linux-mm@kvack.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Nadav Amit <namit@vmware.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Link: https://lkml.kernel.org/r/20180420222023.1C8B2B20@viggo.jf.intel.com

2018-04-25 11:02:50 +02:00

..

amdtopology.c

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

cpu_entry_area.c

x86/pti: Enable global pages for shared areas

2018-04-12 09:05:59 +02:00

debug_pagetables.c

x86/efi: Replace efi_pgd with efi_mm.pgd

2018-03-12 11:05:05 +01:00

dump_pagetables.c

x86/mm: Prevent kernel Oops in PTDUMP code with HIGHPTE=y

2018-04-17 15:43:01 +02:00

extable.c

x86/extable: Mark exception handler functions visible

2018-01-14 20:04:16 +01:00

fault.c

Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2018-04-02 15:45:30 -07:00

highmem_32.c

x86/mm: Audit and remove any unnecessary uses of module.h

2016-07-14 13:04:20 +02:00

hugetlbpage.c

x86/mm: Prevent non-MAP_FIXED mapping across DEFAULT_MAP_WINDOW border

2017-11-16 11:43:11 +01:00

ident_map.c

x86/mm: Do not auto-massage page protections

2018-04-12 09:04:22 +02:00

init_32.c

Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2018-04-15 13:35:29 -07:00

init_64.c

Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2018-04-15 13:35:29 -07:00

init.c

x86/pti: Never implicitly clear _PAGE_GLOBAL for kernel image

2018-04-12 09:06:00 +02:00

iomap_32.c

x86/mm: Do not auto-massage page protections

2018-04-12 09:04:22 +02:00

ioremap.c

x86/mm: Do not auto-massage page protections

2018-04-12 09:04:22 +02:00

kasan_init_64.c

x86/mm: Do not auto-massage page protections

2018-04-12 09:04:22 +02:00

kaslr.c

x86/mm: Replace compile-time checks for 5-level paging with runtime-time checks

2018-02-16 10:48:49 +01:00

kmmio.c

x86/mm: Rename flush_tlb_single() and flush_tlb_one() to __flush_tlb_one_[user|kernel]()

2018-02-15 01:15:52 +01:00

Makefile

x86/mm/sme: Disable stack protection for mem_encrypt_identity.c

2018-02-28 15:24:12 +01:00

mem_encrypt_boot.S

x86/mm/sme, objtool: Annotate indirect call in sme_encrypt_execute()

2018-02-21 09:05:04 +01:00

mem_encrypt_identity.c

x86/mm/sme: Disable stack protection for mem_encrypt_identity.c

2018-02-28 15:24:12 +01:00

mem_encrypt.c

dma/direct: Handle force decryption for DMA coherent buffers in common code

2018-03-20 10:01:59 +01:00

mm_internal.h

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

mmap.c

exec: pass stack rlimit into mm layout functions

2018-04-11 10:28:37 -07:00

mmio-mod.c

x86: do not use print_symbol()

2018-01-05 15:23:01 +01:00

mpx.c

Merge branch 'x86/mpx' into x86/asm, to pick up dependent commits

2017-11-08 10:55:48 +01:00

numa_32.c

x86/mm/32: Remove unused node_memmap_size_bytes() & CONFIG_NEED_NODE_MEMMAP_SIZE logic

2018-03-27 08:45:02 +02:00

numa_64.c

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

numa_emulation.c

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

numa_internal.h

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

numa.c

Merge branch 'x86/boot' into x86/mm, to avoid conflict

2017-04-11 08:56:05 +02:00

pageattr-test.c

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

pageattr.c

x86/pti: Fix boot warning from Global-bit setting

2018-04-25 11:02:50 +02:00

pat_internal.h

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

pat_rbtree.c

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

pat.c

x86/mm: add a function to check if a pfn is UC/UC-/WC

2018-01-16 16:40:09 +01:00

pf_in.c

x86/mm: Audit and remove any unnecessary uses of module.h

2016-07-14 13:04:20 +02:00

pf_in.h

x86 mmiotrace: move files into arch/x86/mm/.

2008-05-24 11:25:37 +02:00

pgtable_32.c

x86/mm: Rename flush_tlb_single() and flush_tlb_one() to __flush_tlb_one_[user|kernel]()

2018-02-15 01:15:52 +01:00

pgtable.c

x86/pgtable: Don't set huge PUD/PMD on non-leaf entries

2018-04-12 09:41:41 +02:00

physaddr.c

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

physaddr.h

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

pkeys.c

x86/fpu: Rename fpu::fpstate_active to fpu::initialized

2017-09-26 09:43:36 +02:00

pti.c

x86/pti: Reduce amount of kernel text allowed to be Global

2018-04-25 11:02:50 +02:00

setup_nx.c

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

srat.c

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02 11:10:55 +01:00

testmmiotrace.c

Annotate hardware config module parameters in arch/x86/mm/

2017-04-04 16:54:21 +01:00

tlb.c

Merge branch 'x86/mm' into efi/core

2018-03-12 10:03:09 +01:00