diff options
| author | Andrey Konovalov <andreyknvl@google.com> | 2022-06-09 20:18:46 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-08-17 14:42:36 +0200 |
| commit | 043fcdc2876029c45bf781a3f9ef31fc0b35e881 (patch) | |
| tree | 733f6a62b91f6e8e6211a2c7d87f41b0b8458e7e | |
| parent | 11e008e599700f1ff1f39b9190fdb2fee972996b (diff) | |
mm: introduce clear_highpage_kasan_tagged
commit d9da8f6cf55eeca642c021912af1890002464c64 upstream.
Add a clear_highpage_kasan_tagged() helper that does clear_highpage() on a
page potentially tagged by KASAN.
This helper is used by the following patch.
Link: https://lkml.kernel.org/r/4471979b46b2c487787ddcd08b9dc5fedd1b6ffd.1654798516.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | include/linux/highmem.h | 10 | ||||
| -rw-r--r-- | mm/page_alloc.c | 8 |
2 files changed, 12 insertions, 6 deletions
diff --git a/include/linux/highmem.h b/include/linux/highmem.h index 39bb9b47fa9c..7037c6bed55c 100644 --- a/include/linux/highmem.h +++ b/include/linux/highmem.h @@ -218,6 +218,16 @@ static inline void clear_highpage(struct page *page) kunmap_local(kaddr); } +static inline void clear_highpage_kasan_tagged(struct page *page) +{ + u8 tag; + + tag = page_kasan_tag(page); + page_kasan_tag_reset(page); + clear_highpage(page); + page_kasan_tag_set(page, tag); +} + #ifndef __HAVE_ARCH_TAG_CLEAR_HIGHPAGE static inline void tag_clear_highpage(struct page *page) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 135a081edb82..a8bd356a4d1e 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1287,12 +1287,8 @@ static void kernel_init_free_pages(struct page *page, int numpages) /* s390's use of memset() could override KASAN redzones. */ kasan_disable_current(); - for (i = 0; i < numpages; i++) { - u8 tag = page_kasan_tag(page + i); - page_kasan_tag_reset(page + i); - clear_highpage(page + i); - page_kasan_tag_set(page + i, tag); - } + for (i = 0; i < numpages; i++) + clear_highpage_kasan_tagged(page + i); kasan_enable_current(); } |