[PATCH v8 21/43] kasan: kasan_non_canonical_hook only for software modes

Andrey Konovalov
2020-11-04T23:20:03Z

This is a preparatory commit for the upcoming addition of a new hardware
tag-based (MTE-based) KASAN mode.

kasan_non_canonical_hook() is only applicable to KASAN modes that use
shadow memory, and won't be needed for hardware tag-based KASAN.

No functional changes for software modes.

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Marco Elver <elver@google.com>
---
Change-Id: Icc9f5ef100a2e86f3a4214a0c3131a68266181b2
---
mm/kasan/report.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index 5d5733831ad7..594bad2a3a5e 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -403,7 +403,8 @@ bool kasan_report(unsigned long addr, size_t size, bool is_write,
return ret;
}

-#ifdef CONFIG_KASAN_INLINE
+#if (defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)) && \
+ defined(CONFIG_KASAN_INLINE)
/*
* With CONFIG_KASAN_INLINE, accesses to bogus pointers (outside the high
* canonical half of the address space) cause out-of-bounds shadow memory reads
--
2.29.1.341.ge80a0c044ae-goog