linux_dsm_epyc7002/arch/x86
Dave Hansen 33a709b25a mm/gup, x86/mm/pkeys: Check VMAs and PTEs for protection keys
Today, for normal faults and page table walks, we check the VMA
and/or PTE to ensure that it is compatible with the action.  For
instance, if we get a write fault on a non-writeable VMA, we
SIGSEGV.

We try to do the same thing for protection keys.  Basically, we
try to make sure that if a user does this:

	mprotect(ptr, size, PROT_NONE);
	*ptr = foo;

they see the same effects with protection keys when they do this:

	mprotect(ptr, size, PROT_READ|PROT_WRITE);
	set_pkey(ptr, size, 4);
	wrpkru(0xffffff3f); // access disable pkey 4
	*ptr = foo;

The state to do that checking is in the VMA, but we also
sometimes have to do it on the page tables only, like when doing
a get_user_pages_fast() where we have no VMA.

We add two functions and expose them to generic code:

	arch_pte_access_permitted(pte_flags, write)
	arch_vma_access_permitted(vma, write)

These are, of course, backed up in x86 arch code with checks
against the PTE or VMA's protection key.

But, there are also cases where we do not want to respect
protection keys.  When we ptrace(), for instance, we do not want
to apply the tracer's PKRU permissions to the PTEs from the
process being traced.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Alexey Kardashevskiy <aik@ozlabs.ru>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Boaz Harrosh <boaz@plexistor.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave@sr71.net>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Dominik Dingel <dingel@linux.vnet.ibm.com>
Cc: Dominik Vogt <vogt@linux.vnet.ibm.com>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Low <jason.low2@hp.com>
Cc: Jerome Marchand <jmarchan@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mikulas Patocka <mpatocka@redhat.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Shachar Raindel <raindel@mellanox.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org
Cc: linux-s390@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/20160212210219.14D5D715@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-02-18 09:32:44 +01:00
..
boot x86/cpufeature: Carve out X86_FEATURE_* 2016-01-30 11:22:17 +01:00
configs
crypto Merge branches 'x86/fpu', 'x86/mm' and 'x86/asm' into x86/pkeys 2016-02-16 09:37:37 +01:00
entry x86/syscalls/64: Mark sys_iopl() as using ptregs 2016-02-01 08:53:25 +01:00
ia32
include mm/gup, x86/mm/pkeys: Check VMAs and PTEs for protection keys 2016-02-18 09:32:44 +01:00
kernel x86/fpu, x86/mm/pkeys: Add PKRU xsave fields and data structures 2016-02-16 10:11:14 +01:00
kvm kvm: rename pfn_t to kvm_pfn_t 2016-01-15 17:56:32 -08:00
lguest Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-01-11 16:26:03 -08:00
lib x86/cpufeature: Carve out X86_FEATURE_* 2016-01-30 11:22:17 +01:00
math-emu
mm mm/gup, x86/mm/pkeys: Check VMAs and PTEs for protection keys 2016-02-18 09:32:44 +01:00
net bpf, x86: detect/optimize loading 0 immediates 2015-12-18 16:04:51 -05:00
oprofile x86/cpufeature: Carve out X86_FEATURE_* 2016-01-30 11:22:17 +01:00
pci PCI changes for the v4.5 merge window: 2016-01-21 11:52:16 -08:00
platform Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-01-31 16:17:19 -08:00
power x86/pm: Introduce quirk framework to save/restore extra MSR registers around suspend/resume 2015-11-26 10:04:53 +01:00
purgatory
ras
realmode UBSAN: run-time undefined behavior sanity checker 2016-01-20 17:09:18 -08:00
tools
um x86/cpufeature: Carve out X86_FEATURE_* 2016-01-30 11:22:17 +01:00
video
xen xen: features and fixes for 4.5-rc0 2016-01-12 13:05:36 -08:00
.gitignore
Kbuild
Kconfig mm/core, x86/mm/pkeys: Store protection bits in high VMA flags 2016-02-18 09:31:50 +01:00
Kconfig.cpu
Kconfig.debug x86/cpufeature: Replace the old static_cpu_has() with safe variant 2016-01-30 11:22:18 +01:00
Makefile
Makefile_32.cpu
Makefile.um