Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input

[mirror_ubuntu-artful-kernel.git] / include / linux / uaccess.h

diff --git a/include/linux/uaccess.h b/include/linux/uaccess.h
index 201418d5e15c2b92dc7d7bc73b54f469eb488a35..acdd6f915a8d3d1185d8a13e587824313a5dd14f 100644 (file)
--- a/include/linux/uaccess.h
+++ b/include/linux/uaccess.h
@@ -109,8 +109,11 @@ static inline unsigned long
 _copy_from_user(void *to, const void __user *from, unsigned long n)
 {
        unsigned long res = n;
-       if (likely(access_ok(VERIFY_READ, from, n)))
+       might_fault();
+       if (likely(access_ok(VERIFY_READ, from, n))) {
+               kasan_check_write(to, n);
                res = raw_copy_from_user(to, from, n);
+       }
        if (unlikely(res))
                memset(to + (n - res), 0, res);
        return res;
@@ -124,8 +127,11 @@ _copy_from_user(void *, const void __user *, unsigned long);
 static inline unsigned long
 _copy_to_user(void __user *to, const void *from, unsigned long n)
 {
-       if (access_ok(VERIFY_WRITE, to, n))
+       might_fault();
+       if (access_ok(VERIFY_WRITE, to, n)) {
+               kasan_check_read(from, n);
                n = raw_copy_to_user(to, from, n);
+       }
        return n;
 }
 #else
@@ -133,59 +139,23 @@ extern unsigned long
 _copy_to_user(void __user *, const void *, unsigned long);
 #endif
 
-extern void __compiletime_error("usercopy buffer size is too small")
-__bad_copy_user(void);
-
-static inline void copy_user_overflow(int size, unsigned long count)
-{
-       WARN(1, "Buffer overflow detected (%d < %lu)!\n", size, count);
-}
-
 static __always_inline unsigned long __must_check
 copy_from_user(void *to, const void __user *from, unsigned long n)
 {
-       int sz = __compiletime_object_size(to);
-
-       might_fault();
-       kasan_check_write(to, n);
-
-       if (likely(sz < 0 || sz >= n)) {
-               check_object_size(to, n, false);
+       if (likely(check_copy_size(to, n, false)))
                n = _copy_from_user(to, from, n);
-       } else if (!__builtin_constant_p(n))
-               copy_user_overflow(sz, n);
-       else
-               __bad_copy_user();
-
        return n;
 }
 
 static __always_inline unsigned long __must_check
 copy_to_user(void __user *to, const void *from, unsigned long n)
 {
-       int sz = __compiletime_object_size(from);
-
-       kasan_check_read(from, n);
-       might_fault();
-
-       if (likely(sz < 0 || sz >= n)) {
-               check_object_size(from, n, true);
+       if (likely(check_copy_size(from, n, true)))
                n = _copy_to_user(to, from, n);
-       } else if (!__builtin_constant_p(n))
-               copy_user_overflow(sz, n);
-       else
-               __bad_copy_user();
-
        return n;
 }
 #ifdef CONFIG_COMPAT
 static __always_inline unsigned long __must_check
-__copy_in_user(void __user *to, const void *from, unsigned long n)
-{
-       might_fault();
-       return raw_copy_in_user(to, from, n);
-}
-static __always_inline unsigned long __must_check
 copy_in_user(void __user *to, const void *from, unsigned long n)
 {
        might_fault();