vfio/type1: untag user pointers in vaddr_get_pfn
authorAndrey Konovalov <andreyknvl@google.com>
Wed, 25 Sep 2019 23:49:01 +0000 (16:49 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 26 Sep 2019 00:51:41 +0000 (17:51 -0700)
commit6cf5354c1c4b74fd2e5527db084f163e9d4dae4e
tree6f521d9fa7051a2c8055f7d97a55c8bbbc65407f
parent78063a9dd9637c0450cf6eacc03f42eb1295917f
vfio/type1: untag user pointers in vaddr_get_pfn

This patch is a part of a series that extends kernel ABI to allow to pass
tagged user pointers (with the top byte set to something else other than
0x00) as syscall arguments.

vaddr_get_pfn() uses provided user pointers for vma lookups, which can
only by done with untagged pointers.

Untag user pointers in this function.

Link: http://lkml.kernel.org/r/87422b4d72116a975896f2b19b00f38acbd28f33.1563904656.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Will Deacon <will@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Felix Kuehling <Felix.Kuehling@amd.com>
Cc: Jens Wiklander <jens.wiklander@linaro.org>
Cc: Khalid Aziz <khalid.aziz@oracle.com>
Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/vfio/vfio_iommu_type1.c