diff options
author | Catalin Marinas <catalin.marinas@arm.com> | 2022-06-10 16:21:38 +0100 |
---|---|---|
committer | Will Deacon <will@kernel.org> | 2022-07-07 10:48:37 +0100 |
commit | ed0a6d1d973e9763989b44913ae1bd2a5d5d5777 (patch) | |
tree | 59525214e06904d5cc0c020fea1e4e129d6172d7 /arch/arm64/mm/fault.c | |
parent | a111daf0c53ae91e71fd2bfe7497862d14132e3e (diff) | |
download | linux-ed0a6d1d973e9763989b44913ae1bd2a5d5d5777.tar.gz linux-ed0a6d1d973e9763989b44913ae1bd2a5d5d5777.tar.bz2 linux-ed0a6d1d973e9763989b44913ae1bd2a5d5d5777.zip |
mm: kasan: Ensure the tags are visible before the tag in page->flags
__kasan_unpoison_pages() colours the memory with a random tag and stores
it in page->flags in order to re-create the tagged pointer via
page_to_virt() later. When the tag from the page->flags is read, ensure
that the in-memory tags are already visible by re-ordering the
page_kasan_tag_set() after kasan_unpoison(). The former already has
barriers in place through try_cmpxchg(). On the reader side, the order
is ensured by the address dependency between page->flags and the memory
access.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lore.kernel.org/r/20220610152141.2148929-2-catalin.marinas@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64/mm/fault.c')
0 files changed, 0 insertions, 0 deletions