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Date:   Fri, 14 Aug 2020 19:26:58 +0200
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Subject: [PATCH 16/35] kasan: kasan_non_canonical_hook only for software modes
From:   Andrey Konovalov <andreyknvl@google.com>
To:     Dmitry Vyukov <dvyukov@google.com>,
        Vincenzo Frascino <vincenzo.frascino@arm.com>,
        Catalin Marinas <catalin.marinas@arm.com>,
        kasan-dev@googlegroups.com
Cc:     Andrey Ryabinin <aryabinin@virtuozzo.com>,
        Alexander Potapenko <glider@google.com>,
        Marco Elver <elver@google.com>,
        Evgenii Stepanov <eugenis@google.com>,
        Elena Petrova <lenaptr@google.com>,
        Branislav Rankov <Branislav.Rankov@arm.com>,
        Kevin Brodsky <kevin.brodsky@arm.com>,
        Will Deacon <will.deacon@arm.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org,
        Andrey Konovalov <andreyknvl@google.com>
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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>
---
 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 8ad1ced1607d..2cce7c9beea3 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -376,7 +376,8 @@ 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
-- 
2.28.0.220.ged08abb693-goog