1 files changed, 33 insertions, 22 deletions

diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h
index 0685d74572af..bcaf6fba1b65 100644
--- a/arch/arm64/include/asm/uaccess.h
+++ b/arch/arm64/include/asm/uaccess.h
@@ -21,6 +21,7 @@
 /*
  * User space memory access functions
  */
+#include <linux/kasan-checks.h>
 #include <linux/string.h>
 #include <linux/thread_info.h>
 
@@ -81,19 +82,6 @@ static inline void set_fs(mm_segment_t fs)
 #define segment_eq(a, b)	((a) == (b))
 
 /*
- * Return 1 if addr < current->addr_limit, 0 otherwise.
- */
-#define __addr_ok(addr)							\
-({									\
-	unsigned long flag;						\
-	asm("cmp %1, %0; cset %0, lo"					\
-		: "=&r" (flag)						\
-		: "r" (addr), "0" (current_thread_info()->addr_limit)	\
-		: "cc");						\
-	flag;								\
-})
-
-/*
  * Test whether a block of memory is a valid user space address.
  * Returns 1 if the range is valid, 0 otherwise.
  *
@@ -269,24 +257,47 @@ do {									\
 		-EFAULT;						\
 })
 
-extern unsigned long __must_check __copy_from_user(void *to, const void __user *from, unsigned long n);
-extern unsigned long __must_check __copy_to_user(void __user *to, const void *from, unsigned long n);
+extern unsigned long __must_check __arch_copy_from_user(void *to, const void __user *from, unsigned long n);
+extern unsigned long __must_check __arch_copy_to_user(void __user *to, const void *from, unsigned long n);
 extern unsigned long __must_check __copy_in_user(void __user *to, const void __user *from, unsigned long n);
 extern unsigned long __must_check __clear_user(void __user *addr, unsigned long n);
 
+static inline unsigned long __must_check __copy_from_user(void *to, const void __user *from, unsigned long n)
+{
+	kasan_check_write(to, n);
+	check_object_size(to, n, false);
+	return __arch_copy_from_user(to, from, n);
+}
+
+static inline unsigned long __must_check __copy_to_user(void __user *to, const void *from, unsigned long n)
+{
+	kasan_check_read(from, n);
+	check_object_size(from, n, true);
+	return __arch_copy_to_user(to, from, n);
+}
+
 static inline unsigned long __must_check copy_from_user(void *to, const void __user *from, unsigned long n)
 {
-	if (access_ok(VERIFY_READ, from, n))
-		n = __copy_from_user(to, from, n);
-	else /* security hole - plug it */
-		memset(to, 0, n);
-	return n;
+	unsigned long res = n;
+	kasan_check_write(to, n);
+
+	if (access_ok(VERIFY_READ, from, n)) {
+		check_object_size(to, n, false);
+		res = __arch_copy_from_user(to, from, n);
+	}
+	if (unlikely(res))
+		memset(to + (n - res), 0, res);
+	return res;
 }
 
 static inline unsigned long __must_check copy_to_user(void __user *to, const void *from, unsigned long n)
 {
-	if (access_ok(VERIFY_WRITE, to, n))
-		n = __copy_to_user(to, from, n);
+	kasan_check_read(from, n);
+
+	if (access_ok(VERIFY_WRITE, to, n)) {
+		check_object_size(from, n, true);
+		n = __arch_copy_to_user(to, from, n);
+	}
 	return n;
 }