On Fri, Dec 18, 2020 at 02:02PM -0800, Andrew Morton wrote: > From: Andrey Konovalov <andreyknvl@xxxxxxxxxx> > Subject: kasan: split out shadow.c from common.c > > This is a preparatory commit for the upcoming addition of a new hardware > tag-based (MTE-based) KASAN mode. > > The new mode won't be using shadow memory. Move all shadow-related code > to shadow.c, which is only enabled for software KASAN modes that use > shadow memory. > > No functional changes for software modes. > > Link: https://lkml.kernel.org/r/17d95cfa7d5cf9c4fcd9bf415f2a8dea911668df.1606161801.git.andreyknvl@xxxxxxxxxx > Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> > Signed-off-by: Vincenzo Frascino <vincenzo.frascino@xxxxxxx> > Reviewed-by: Marco Elver <elver@xxxxxxxxxx> > Reviewed-by: Alexander Potapenko <glider@xxxxxxxxxx> > Tested-by: Vincenzo Frascino <vincenzo.frascino@xxxxxxx> > Cc: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx> > Cc: Branislav Rankov <Branislav.Rankov@xxxxxxx> > Cc: Catalin Marinas <catalin.marinas@xxxxxxx> > Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> > Cc: Evgenii Stepanov <eugenis@xxxxxxxxxx> > Cc: Kevin Brodsky <kevin.brodsky@xxxxxxx> > Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx> > Cc: Will Deacon <will.deacon@xxxxxxx> > Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > --- > > mm/kasan/Makefile | 6 > mm/kasan/common.c | 486 ----------------------------------------- > mm/kasan/shadow.c | 518 ++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 523 insertions(+), 487 deletions(-) > > --- a/mm/kasan/common.c~kasan-split-out-shadowc-from-commonc > +++ a/mm/kasan/common.c > @@ -1,6 +1,6 @@ > // SPDX-License-Identifier: GPL-2.0 > /* > - * This file contains common generic and tag-based KASAN code. > + * This file contains common KASAN code. > * > * Copyright (c) 2014 Samsung Electronics Co., Ltd. > * Author: Andrey Ryabinin <ryabinin.a.a@xxxxxxxxx> > @@ -13,7 +13,6 @@ > #include <linux/init.h> > #include <linux/kasan.h> > #include <linux/kernel.h> > -#include <linux/kmemleak.h> > #include <linux/linkage.h> > #include <linux/memblock.h> > #include <linux/memory.h> > @@ -26,12 +25,8 @@ > #include <linux/stacktrace.h> > #include <linux/string.h> > #include <linux/types.h> > -#include <linux/vmalloc.h> > #include <linux/bug.h> > > -#include <asm/cacheflush.h> > -#include <asm/tlbflush.h> > - > #include "kasan.h" > #include "../slab.h" > [...] > -/* > - * Poisons the shadow memory for 'size' bytes starting from 'addr'. > - * Memory addresses should be aligned to KASAN_GRANULE_SIZE. > - */ > -void poison_range(const void *address, size_t size, u8 value) > -{ > - void *shadow_start, *shadow_end; > - > - /* > - * Perform shadow offset calculation based on untagged address, as > - * some of the callers (e.g. kasan_poison_object_data) pass tagged > - * addresses to this function. > - */ > - address = reset_tag(address); > - The moved lines do not mention kfence... (The same commit in -next does.) > - shadow_start = kasan_mem_to_shadow(address); > - shadow_end = kasan_mem_to_shadow(address + size); > - > - __memset(shadow_start, value, shadow_end - shadow_start); > -} [...] > --- /dev/null > +++ a/mm/kasan/shadow.c > @@ -0,0 +1,518 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * This file contains KASAN runtime code that manages shadow memory for > + * generic and software tag-based KASAN modes. > + * > + * Copyright (c) 2014 Samsung Electronics Co., Ltd. > + * Author: Andrey Ryabinin <ryabinin.a.a@xxxxxxxxx> > + * > + * Some code borrowed from https://github.com/xairy/kasan-prototype by > + * Andrey Konovalov <andreyknvl@xxxxxxxxx> > + */ > + > +#include <linux/init.h> > +#include <linux/kasan.h> > +#include <linux/kernel.h> > +#include <linux/kfence.h> This is the first time kfence is mentioned. Is this correct? Is my assumption correct that the kasan changes and kfence changes are to be swapped? Thanks, -- Marco