[PATCH v11 09/24] arm64: move untagged_addr macro from uaccess.h to memory.h

Andrey Konovalov
2018-11-19T17:27:14Z

Move the untagged_addr() macro from arch/arm64/include/asm/uaccess.h
to arch/arm64/include/asm/memory.h to be later reused by KASAN.

Also make the untagged_addr() macro accept all kinds of address types
(void *, unsigned long, etc.). This allows not to specify type casts in
each place where the macro is used. This is done by using __typeof__.

Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
---
arch/arm64/include/asm/memory.h | 8 ++++++++
arch/arm64/include/asm/uaccess.h | 7 -------
2 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h
index 05fbc7ffcd31..deb95be44392 100644
--- a/arch/arm64/include/asm/memory.h
+++ b/arch/arm64/include/asm/memory.h
@@ -73,6 +73,14 @@
#define KERNEL_START _text
#define KERNEL_END _end

+/*
+ * When dealing with data aborts, watchpoints, or instruction traps we may end
+ * up with a tagged userland pointer. Clear the tag to get a sane pointer to
+ * pass on to access_ok(), for instance.
+ */
+#define untagged_addr(addr) \
+ (__typeof__(addr))sign_extend64((__u64)(addr), 55)
+
/*
* Generic and tag-based KASAN require 1/8th and 1/16th of the kernel virtual
* address space for the shadow region respectively. They can bloat the stack
diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h
index 07c34087bd5e..281a1e47263d 100644
--- a/arch/arm64/include/asm/uaccess.h
+++ b/arch/arm64/include/asm/uaccess.h
@@ -96,13 +96,6 @@ static inline unsigned long __range_ok(const void __user *addr, unsigned long si
return ret;
}

-/*
- * When dealing with data aborts, watchpoints, or instruction traps we may end
- * up with a tagged userland pointer. Clear the tag to get a sane pointer to
- * pass on to access_ok(), for instance.
- */
-#define untagged_addr(addr) sign_extend64(addr, 55)
-
#define access_ok(type, addr, size) __range_ok(addr, size)
#define user_addr_max get_fs

--
2.19.1.1215.g8438c0b245-goog