[PATCH kcsan 10/32] copy_to_user, copy_from_user: Use generic instrumented.h

From: paulmck
Date: Mon Mar 09 2020 - 15:05:58 EST


From: Marco Elver <elver@xxxxxxxxxx>

This replaces the KASAN instrumentation with generic instrumentation,
implicitly adding KCSAN instrumentation support.

For KASAN no functional change is intended.

Suggested-by: Arnd Bergmann <arnd@xxxxxxxx>
Signed-off-by: Marco Elver <elver@xxxxxxxxxx>
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
---
include/linux/uaccess.h | 14 +++++++-------
lib/usercopy.c | 7 ++++---
2 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h
index 67f01601..8a215c5 100644
--- a/include/linux/uaccess.h
+++ b/include/linux/uaccess.h
@@ -2,9 +2,9 @@
#ifndef __LINUX_UACCESS_H__
#define __LINUX_UACCESS_H__

+#include <linux/instrumented.h>
#include <linux/sched.h>
#include <linux/thread_info.h>
-#include <linux/kasan-checks.h>

#define uaccess_kernel() segment_eq(get_fs(), KERNEL_DS)

@@ -58,7 +58,7 @@
static __always_inline __must_check unsigned long
__copy_from_user_inatomic(void *to, const void __user *from, unsigned long n)
{
- kasan_check_write(to, n);
+ instrument_copy_from_user(to, from, n);
check_object_size(to, n, false);
return raw_copy_from_user(to, from, n);
}
@@ -67,7 +67,7 @@ static __always_inline __must_check unsigned long
__copy_from_user(void *to, const void __user *from, unsigned long n)
{
might_fault();
- kasan_check_write(to, n);
+ instrument_copy_from_user(to, from, n);
check_object_size(to, n, false);
return raw_copy_from_user(to, from, n);
}
@@ -88,7 +88,7 @@ __copy_from_user(void *to, const void __user *from, unsigned long n)
static __always_inline __must_check unsigned long
__copy_to_user_inatomic(void __user *to, const void *from, unsigned long n)
{
- kasan_check_read(from, n);
+ instrument_copy_to_user(to, from, n);
check_object_size(from, n, true);
return raw_copy_to_user(to, from, n);
}
@@ -97,7 +97,7 @@ static __always_inline __must_check unsigned long
__copy_to_user(void __user *to, const void *from, unsigned long n)
{
might_fault();
- kasan_check_read(from, n);
+ instrument_copy_to_user(to, from, n);
check_object_size(from, n, true);
return raw_copy_to_user(to, from, n);
}
@@ -109,7 +109,7 @@ _copy_from_user(void *to, const void __user *from, unsigned long n)
unsigned long res = n;
might_fault();
if (likely(access_ok(from, n))) {
- kasan_check_write(to, n);
+ instrument_copy_from_user(to, from, n);
res = raw_copy_from_user(to, from, n);
}
if (unlikely(res))
@@ -127,7 +127,7 @@ _copy_to_user(void __user *to, const void *from, unsigned long n)
{
might_fault();
if (access_ok(to, n)) {
- kasan_check_read(from, n);
+ instrument_copy_to_user(to, from, n);
n = raw_copy_to_user(to, from, n);
}
return n;
diff --git a/lib/usercopy.c b/lib/usercopy.c
index cbb4d9e..4bb1c5e 100644
--- a/lib/usercopy.c
+++ b/lib/usercopy.c
@@ -1,6 +1,7 @@
// SPDX-License-Identifier: GPL-2.0
-#include <linux/uaccess.h>
#include <linux/bitops.h>
+#include <linux/instrumented.h>
+#include <linux/uaccess.h>

/* out-of-line parts */

@@ -10,7 +11,7 @@ unsigned long _copy_from_user(void *to, const void __user *from, unsigned long n
unsigned long res = n;
might_fault();
if (likely(access_ok(from, n))) {
- kasan_check_write(to, n);
+ instrument_copy_from_user(to, from, n);
res = raw_copy_from_user(to, from, n);
}
if (unlikely(res))
@@ -25,7 +26,7 @@ unsigned long _copy_to_user(void __user *to, const void *from, unsigned long n)
{
might_fault();
if (likely(access_ok(to, n))) {
- kasan_check_read(from, n);
+ instrument_copy_to_user(to, from, n);
n = raw_copy_to_user(to, from, n);
}
return n;
--
2.9.5