Craig Bergstrom ce56a86e2a x86/mm: Limit mmap() of /dev/mem to valid physical addresses ...

Currently, it is possible to mmap() any offset from /dev/mem.  If a
program mmaps() /dev/mem offsets outside of the addressable limits
of a system, the page table can be corrupted by setting reserved bits.

For example if you mmap() offset 0x0001000000000000 of /dev/mem on an
x86_64 system with a 48-bit bus, the page fault handler will be called
with error_code set to RSVD.  The kernel then crashes with a page table
corruption error.

This change prevents this page table corruption on x86 by refusing
to mmap offsets higher than the highest valid address in the system.

Signed-off-by: Craig Bergstrom <craigb@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Toshi Kani <toshi.kani@hp.com>
Cc: dsafonov@virtuozzo.com
Cc: kirill.shutemov@linux.intel.com
Cc: mhocko@suse.com
Cc: oleg@redhat.com
Link: http://lkml.kernel.org/r/20171019192856.39672-1-craigb@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

2017-10-20 09:48:00 +02:00

..

boot

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

2017-09-07 09:42:35 -07:00

configs

Merge branch 'x86/urgent' into x86/asm, to pick up fixes

2017-08-10 13:14:15 +02:00

crypto

crypto: x86/twofish - Fix RBP usage

2017-09-20 17:42:38 +08:00

entry

x86/unwind: Use MSB for frame pointer encoding on 32-bit

2017-10-10 12:49:48 +02:00

events

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

2017-10-14 15:16:49 -04:00

hyperv

x86/hyperv: Fix hypercalls with extended CPU ranges for TLB flushing

2017-10-10 12:54:56 +02:00

ia32

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

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

include

x86/mm: Limit mmap() of /dev/mem to valid physical addresses

2017-10-20 09:48:00 +02:00

kernel

x86/microcode/intel: Disable late loading on model 79

2017-10-18 15:20:20 +02:00

kvm

KVM: nVMX: fix guest CR4 loading when emulating L2 to L1 exit

2017-10-12 13:54:56 +02:00

lib

x86/boot: Add early cmdline parsing for options with arguments

2017-07-18 11:38:06 +02:00

math-emu

x86/fpu: Rename fpu__activate_curr() to fpu__initialize()

2017-09-26 09:43:44 +02:00

mm

x86/mm: Limit mmap() of /dev/mem to valid physical addresses

2017-10-20 09:48:00 +02:00

net

bpf: fix bpf_tail_call() x64 JIT

2017-10-03 16:04:44 -07:00

oprofile

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pci

dmi: Mark all struct dmi_system_id instances const

2017-09-14 11:59:30 +02:00

platform

Merge branch 'i2c/for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

2017-09-09 14:18:40 -07:00

power

dmi: Mark all struct dmi_system_id instances const

2017-09-14 11:59:30 +02:00

purgatory

kasan: do not sanitize kexec purgatory

2017-03-31 17:13:30 -07:00

ras

x86/mce: Merge mce_amd_inj into mce-inject

2017-06-14 07:32:07 +02:00

realmode

x86/boot/realmode: Check for memory encryption on the APs

2017-07-18 11:38:04 +02:00

tools

x86/tools: Fix gcc-7 warning in relocs.c

2016-12-19 11:50:24 +01:00

um

um: remove a stray tab

2017-09-13 22:36:27 +02:00

video

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xen

Merge tag 'for-linus-4.14c-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

2017-10-13 11:35:03 -07:00

.gitignore

…

Kbuild

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

2017-09-07 09:25:15 -07:00

Kconfig

Merge tag 'libnvdimm-for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

2017-09-11 13:10:57 -07:00

Kconfig.cpu

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Kconfig.debug

Merge branch 'x86/asm' into locking/core

2017-08-18 10:29:54 +02:00

Makefile

x86/build: Use cc-option to validate stack alignment parameter

2017-08-21 09:53:15 +02:00

Makefile_32.cpu

kbuild: remove cc-option-align

2017-06-25 12:43:00 +09:00

Makefile.um

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