[PATCH v13 11/25] kasan, arm64: untag address in _virt_addr_is_linear
From: Andrey Konovalov
Date: Thu Dec 06 2018 - 07:25:11 EST
virt_addr_is_linear (which is used by virt_addr_valid) assumes that the
top byte of the address is 0xff, which isn't always the case with
tag-based KASAN.
This patch resets the tag in this macro.
Reviewed-by: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
Reviewed-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
---
arch/arm64/include/asm/memory.h | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h
index 83c1366a1233..5fe2353f111b 100644
--- a/arch/arm64/include/asm/memory.h
+++ b/arch/arm64/include/asm/memory.h
@@ -322,9 +322,10 @@ static inline void *phys_to_virt(phys_addr_t x)
#endif
#endif
-#define _virt_addr_is_linear(kaddr) (((u64)(kaddr)) >= PAGE_OFFSET)
-#define virt_addr_valid(kaddr) (_virt_addr_is_linear(kaddr) && \
- _virt_addr_valid(kaddr))
+#define _virt_addr_is_linear(kaddr) \
+ (__tag_reset((u64)(kaddr)) >= PAGE_OFFSET)
+#define virt_addr_valid(kaddr) \
+ (_virt_addr_is_linear(kaddr) && _virt_addr_valid(kaddr))
#include <asm-generic/memory_model.h>
--
2.20.0.rc1.387.gf8505762e3-goog