Switch flock copyin/copyout primitives to copy_{from,to}_user()

... and lose HAVE_ARCH_...; if copy_{to,from}_user() on an
architecture sucks badly enough to make it a problem, we have
a worse problem.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/fcntl.c b/fs/fcntl.c
index afed3b364979ac85766171fb39e66ceefe0c1175..f525bc75c07d504b3fec35690d63fb84afda40c1 100644 (file)
--- a/fs/fcntl.c
+++ b/fs/fcntl.c
@@ -452,57 +452,56 @@ out:
 #endif
 
 #ifdef CONFIG_COMPAT
+/* careful - don't use anywhere else */
+#define copy_flock_fields(from, to)            \
+       (to).l_type = (from).l_type;            \
+       (to).l_whence = (from).l_whence;        \
+       (to).l_start = (from).l_start;          \
+       (to).l_len = (from).l_len;              \
+       (to).l_pid = (from).l_pid;
+
 static int get_compat_flock(struct flock *kfl, struct compat_flock __user *ufl)
 {
-       if (!access_ok(VERIFY_READ, ufl, sizeof(*ufl)) ||
-           __get_user(kfl->l_type, &ufl->l_type) ||
-           __get_user(kfl->l_whence, &ufl->l_whence) ||
-           __get_user(kfl->l_start, &ufl->l_start) ||
-           __get_user(kfl->l_len, &ufl->l_len) ||
-           __get_user(kfl->l_pid, &ufl->l_pid))
+       struct compat_flock fl;
+
+       if (copy_from_user(&fl, ufl, sizeof(struct compat_flock)))
                return -EFAULT;
+       copy_flock_fields(*kfl, fl);
        return 0;
 }
 
-static int put_compat_flock(struct flock *kfl, struct compat_flock __user *ufl)
+static int get_compat_flock64(struct flock *kfl, struct compat_flock64 __user *ufl)
 {
-       if (!access_ok(VERIFY_WRITE, ufl, sizeof(*ufl)) ||
-           __put_user(kfl->l_type, &ufl->l_type) ||
-           __put_user(kfl->l_whence, &ufl->l_whence) ||
-           __put_user(kfl->l_start, &ufl->l_start) ||
-           __put_user(kfl->l_len, &ufl->l_len) ||
-           __put_user(kfl->l_pid, &ufl->l_pid))
+       struct compat_flock64 fl;
+
+       if (copy_from_user(&fl, ufl, sizeof(struct compat_flock64)))
                return -EFAULT;
+       copy_flock_fields(*kfl, fl);
        return 0;
 }
 
-#ifndef HAVE_ARCH_GET_COMPAT_FLOCK64
-static int get_compat_flock64(struct flock *kfl, struct compat_flock64 __user *ufl)
+static int put_compat_flock(struct flock *kfl, struct compat_flock __user *ufl)
 {
-       if (!access_ok(VERIFY_READ, ufl, sizeof(*ufl)) ||
-           __get_user(kfl->l_type, &ufl->l_type) ||
-           __get_user(kfl->l_whence, &ufl->l_whence) ||
-           __get_user(kfl->l_start, &ufl->l_start) ||
-           __get_user(kfl->l_len, &ufl->l_len) ||
-           __get_user(kfl->l_pid, &ufl->l_pid))
+       struct compat_flock fl;
+
+       memset(&fl, 0, sizeof(struct compat_flock));
+       copy_flock_fields(fl, *kfl);
+       if (copy_to_user(ufl, &fl, sizeof(struct compat_flock)))
                return -EFAULT;
        return 0;
 }
-#endif
 
-#ifndef HAVE_ARCH_PUT_COMPAT_FLOCK64
 static int put_compat_flock64(struct flock *kfl, struct compat_flock64 __user *ufl)
 {
-       if (!access_ok(VERIFY_WRITE, ufl, sizeof(*ufl)) ||
-           __put_user(kfl->l_type, &ufl->l_type) ||
-           __put_user(kfl->l_whence, &ufl->l_whence) ||
-           __put_user(kfl->l_start, &ufl->l_start) ||
-           __put_user(kfl->l_len, &ufl->l_len) ||
-           __put_user(kfl->l_pid, &ufl->l_pid))
+       struct compat_flock64 fl;
+
+       memset(&fl, 0, sizeof(struct compat_flock64));
+       copy_flock_fields(fl, *kfl);
+       if (copy_to_user(ufl, &fl, sizeof(struct compat_flock64)))
                return -EFAULT;
        return 0;
 }
-#endif
+#undef copy_flock_fields
 
 static unsigned int
 convert_fcntl_cmd(unsigned int cmd)